1
|
Association of Autologous Tumor Lysate-Loaded Dendritic Cell Vaccination With Extension of Survival Among Patients With Newly Diagnosed and Recurrent Glioblastoma: A Phase 3 Prospective Externally Controlled Cohort Trial. JAMA Oncol 2023; 9:112-121. [PMID: 36394838 PMCID: PMC9673026 DOI: 10.1001/jamaoncol.2022.5370] [Citation(s) in RCA: 123] [Impact Index Per Article: 123.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 08/27/2022] [Indexed: 11/19/2022]
Abstract
Importance Glioblastoma is the most lethal primary brain cancer. Clinical outcomes for glioblastoma remain poor, and new treatments are needed. Objective To investigate whether adding autologous tumor lysate-loaded dendritic cell vaccine (DCVax-L) to standard of care (SOC) extends survival among patients with glioblastoma. Design, Setting, and Participants This phase 3, prospective, externally controlled nonrandomized trial compared overall survival (OS) in patients with newly diagnosed glioblastoma (nGBM) and recurrent glioblastoma (rGBM) treated with DCVax-L plus SOC vs contemporaneous matched external control patients treated with SOC. This international, multicenter trial was conducted at 94 sites in 4 countries from August 2007 to November 2015. Data analysis was conducted from October 2020 to September 2021. Interventions The active treatment was DCVax-L plus SOC temozolomide. The nGBM external control patients received SOC temozolomide and placebo; the rGBM external controls received approved rGBM therapies. Main Outcomes and Measures The primary and secondary end points compared overall survival (OS) in nGBM and rGBM, respectively, with contemporaneous matched external control populations from the control groups of other formal randomized clinical trials. Results A total of 331 patients were enrolled in the trial, with 232 randomized to the DCVax-L group and 99 to the placebo group. Median OS (mOS) for the 232 patients with nGBM receiving DCVax-L was 19.3 (95% CI, 17.5-21.3) months from randomization (22.4 months from surgery) vs 16.5 (95% CI, 16.0-17.5) months from randomization in control patients (HR = 0.80; 98% CI, 0.00-0.94; P = .002). Survival at 48 months from randomization was 15.7% vs 9.9%, and at 60 months, it was 13.0% vs 5.7%. For 64 patients with rGBM receiving DCVax-L, mOS was 13.2 (95% CI, 9.7-16.8) months from relapse vs 7.8 (95% CI, 7.2-8.2) months among control patients (HR, 0.58; 98% CI, 0.00-0.76; P < .001). Survival at 24 and 30 months after recurrence was 20.7% vs 9.6% and 11.1% vs 5.1%, respectively. Survival was improved in patients with nGBM with methylated MGMT receiving DCVax-L compared with external control patients (HR, 0.74; 98% CI, 0.55-1.00; P = .03). Conclusions and Relevance In this study, adding DCVax-L to SOC resulted in clinically meaningful and statistically significant extension of survival for patients with both nGBM and rGBM compared with contemporaneous, matched external controls who received SOC alone. Trial Registration ClinicalTrials.gov Identifier: NCT00045968.
Collapse
|
2
|
Postmortem study of organ-specific toxicity in glioblastoma patients treated with a combination of temozolomide, irinotecan and bevacizumab. J Neurooncol 2022; 160:221-231. [PMID: 36203027 DOI: 10.1007/s11060-022-04144-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 09/20/2022] [Indexed: 11/30/2022]
Abstract
PURPOSE Systemic chemotherapy including monotherapy with temozolomide (TMZ) or bevacizumab (BEV); two-drug combinations, such as irinotecan (IRI) and BEV, TMZ and BEV and a three-drug combination with TMZ, IRI and BEV (TIB) have been used in treating patients with progressive high-grade gliomas including glioblastoma (GBM). Most patients tolerated these regimens well with known side effects of hypertension, proteinuria, and reversible clinical myelosuppression (CM). However, organ- or system- specific toxicities from chemotherapy agents have never been examined by postmortem study. This is the largest cohort used to address this issue in glioma patients. METHODS Postmortem tissues (from all major systems and organs) were prospectively collected and examined by standard institution autopsy and neuropathological procedures from 76 subjects, including gliomas (N = 68, 44/M, and 24/F) and brain metastases (N = 8, 5/M, and 3/F) between 2009 and 2019. Standard hematoxylin and eosin (H&E) were performed on all major organs including brain specimens. Electronic microscopic (EM) study was carried out on 14 selected subject's kidney samples per standard EM protocol. Medical records were reviewed with adverse events (AEs) analyzed and graded according to the Common Terminology Criteria for Adverse Events (CTCAE), version 4.03. A swimmer plot was utilized to visualize the timelines of patient history by treatment group. The binary logistic regression models were performed to explore any associations between treatment strategies and incident myelosuppression. RESULTS Twenty-four glioma subjects were treated with TIB [median: 5.5 (range: 1-25) cycles] at tumor recurrence. Exposure to IRI significantly increased the frequency of CM (p = 0.05). No unexpected adverse events clinically, or permanent end-organ damage during postmortem examination was identified in glioma subjects who had received standard or prolonged duration of BEV, TMZ or TIB regimen-based chemotherapies except rare events of bone marrow suppression. The most common causes of death (COD) were tumor progression (63.2%, N = 43) followed by aspiration pneumonia (48.5%, N = 33) in glioma subjects. No COD was attributed to acute toxicity from TIB. The study also demonstrated that postmortem kidney specimen is unsuitable for studying renal ultrastructural pathological changes due to autolysis. CONCLUSION There is no organ or system toxicity by postmortem examinations among glioma subjects who received BEV, TMZ or TIB regimen-based chemotherapies regardless of durations except for occasional bone marrow suppression and reversible myelosuppression clinically. IRI, but not the extended use of TMZ, significantly increased CM in recurrent glioma patients. COD most commonly resulted from glioma tumor progression with infiltration to brain stem and aspiration pneumonia.
Collapse
|
3
|
[The value of immunohistochemical expression of Ki-67 and CD34 in differentiating ductal carcinoma in situ from ductal carcinoma in situ-like invasive breast cancer]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2022; 51:838-842. [PMID: 36097899 DOI: 10.3760/cma.j.cn112151-20220428-00339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Objective: To investigate the expression of Ki-67 and CD34 in the differential diagnosis of ductal carcinoma in situ (DCIS) and DCIS-like invasive breast cancer (DLIBC). Methods: A total of 100 cases of DCIS and 150 cases of DLIBC diagnosed pathologically in Yantai Yuhuangding Hospital from January 2019 to March 2022 were collected. The expression of p63, CK5/6, Ki-67 and CD34 in both groups were detected by immunohistochemical (IHC) staining and evaluated. Results: The 100 cases of DCIS included 11 cases of low-grade DCIS, 28 cases of intermediate-grade DCIS and 61 cases of high-grade DCIS. IHC staining of p63 and CK5/6 showed the myoepithelial cells around cancerous duct were complete or partial absence. Ki-67 expression showed two patterns: high expression in the basal layers and scattered expression within the tumor. Most cases showed mainly high basal expression (77/100, 77%), and the proportion of this pattern was significantly different between low grade and high grade DCIS (P<0.05). All cases showed complete CD34 expression surrounding the cancerous duct with different proportion (vascular necklace) suggested small vessels proliferation. The 150 cases of DLIBC included 142 cases of invasive ductal carcinoma (IDC) (three cases of basal-like breast cancer was included), two cases of secretory carcinoma, three cases of solid papillary carcinoma, two cases of adenoid cystic carcinoma and one case of acinar cell carcinoma. Among 142 cases of IDC, 13 cases were grade Ⅰ, 77 were grade Ⅱ and 52 were grade Ⅲ. IHC staining of p63 showed complete absence of myoepithelium. CK5/6 was negative in most cases and only positively expressed within the tumor in 3 cases of basal-like breast cancer. Ki-67 indicated a scattered expression pattern within the tumor. In most cases, CD34 immunostaining showed scattered positive blood vessels within the tumor while only two cases showed incomplete expression of CD34 around the tumor (2/150, 1.3%). The different expression patterns of Ki-67 and CD34 in DCIS and DLIBC was statistically significant (P<0.05). Conclusions: The different expression patterns of Ki-67 and CD34 are helpful to distinguish DLIBC from DCIS. The appearance of "vascular necklace" with CD34 and the high expression of Ki-67 around the cancerous duct highly support the diagnosis of DCIS, and the scattered expression pattern of CD34 supports DLIBC.
Collapse
|
4
|
Facial nerve outcomes following gamma knife radiosurgery for subtotally resected vestibular schwannomas: Early versus delayed timing of therapy. Clin Neurol Neurosurg 2020; 198:106148. [PMID: 32823189 DOI: 10.1016/j.clineuro.2020.106148] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 07/12/2020] [Accepted: 08/09/2020] [Indexed: 11/24/2022]
Abstract
OBJECTIVES Initially treating vestibular schwannomas (VSs) with subtotal resection (STR) followed by Gamma Knife radiosurgery (GKRS) for progression of tumor residual is a strategy that balances maximal tumor resection with preservation of neurological function. The effect of timing of GKRS for residual and recurrent VSs remains poorly defined. We developed a simple and practical treatment algorithm for the timing of GKRS after STR of VSs and reviewed our follow-up results to determine outcomes between patients treated with early vs. late GKRS. PATIENTS AND METHODS Patients that underwent STR between 1999 and 2017 for a VS at Tufts Medical Center were identified and included in the study cohort. Patients who received GKRS ≤ 12 months after STR were included in the early intervention group. Patients who received GKRS > 12 months after STR or did not have tumor progression on follow-up thus not requiring GKRS were included in the observation/delayed intervention group. RESULTS STR of VSs was performed on 23 patients. Mean patient age at the time of STR was 53.0 years (range: 20-86.2). The mean follow-up was 4.2 years (range: 1 month-15.5 years). Patients most frequently presented with hearing loss. There were 5 patients (21.7 %) in the early intervention group and 18 (78.3 %) patients in the observation/delayed intervention group. Ten of 23 patients (43.5 %) required GKRS. Thirteen (56.5 %) did not receive GKRS. None of the patients in the early intervention group or the observation/delayed intervention group had changes in House-Brackmann (HB) Grade either after GKRS or at the end of the study period. CONCLUSIONS GKRS of residual or recurrent tumor is safe following STR of VS and appears to carry a low risk of worsening facial nerve function when performed for progressive tumor growth.
Collapse
|
5
|
Case Report: Metastasis of a Trigeminal Malignant Peripheral Nerve Sheath Tumor to the Corpus Callosum. Neurosurgery 2019. [PMID: 29518229 DOI: 10.1093/neuros/nyy016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND AND IMPORTANCE Malignant peripheral nerve sheath tumors (MPNST) are relatively rare tumors of peripheral nerves that are notable for their locally aggressive nature, ability to metastasize, poor prognosis, and association with Neurofibromatosis type I. We present the case of a patient with a trigeminal nerve MPNST who developed an unusual metastasis to the corpus callosum, in the absence of any other central nervous system or systemic metastatic disease. We review the pathology and presentation of MPNST. CLINICAL PRESENTATION A 53-yr-old woman presented with a 1-yr history of paroxysmal facial pain and dysesthesias in the right V1 and V2 distributions of the trigeminal nerve. She was initially diagnosed with trigeminal neuralgia although further imaging showed a cavernous sinus mass extending along the trigeminal nerve. She later developed an isolated lesion in the corpus callosum that was biopsied and consistent with MPNST. CONCLUSION This case reviews the pathology and aggressive nature of MPNST and demonstrates an unusual site of metastasis. Clinicians should remain aware that MPNST can metastasize to sites in the central nervous system as well as systemically. Furthermore, clinicians should have a high index of suspicion for secondary causes of trigeminal neuralgia in cases with atypical features.
Collapse
|
6
|
A Comparison of the Existing Wellness Programs in Neurosurgery and Institution Champion's Perspectives. Neurosurgery 2018; 84:1149-1155. [DOI: 10.1093/neuros/nyy418] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 08/10/2018] [Indexed: 11/12/2022] Open
Abstract
Abstract
Once the accepted norm during Harvey Cushing's time, the mantra of work to the exclusion of family and lifestyle is now recognized as deleterious to overall well-being. A number of neurosurgical residency training programs have implemented wellness programs to enhance the physical, mental, and emotional well-being of trainees and faculty. This manuscript highlights existing organized wellness education within neurosurgery residency programs in order to describe the motivations behind development, structure, and potential implementation strategies, cost of implementation, and identify successes and barriers in the integration process. This manuscript is designed to serve as a “how-to” guide for other programs who may identify a need in their own trainees and begins the discussion of how to develop wellness, leadership, grit, and resiliency within our future generation of neurosurgeons.
Collapse
|
7
|
High p16 Expression Is Associated with Malignancy and Shorter Disease-Free Survival Time in Solitary Fibrous Tumor/Hemangiopericytoma. J Neurol Surg B Skull Base 2018; 80:232-238. [PMID: 31143564 DOI: 10.1055/s-0038-1669419] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Accepted: 07/17/2018] [Indexed: 02/07/2023] Open
Abstract
Objective Solitary fibrous tumors (SFT) and hemangiopericytomas (HPC) are now classified along a single spectrum of fibroblastic mesenchymal tumors with NAB2-STAT6 fusion. This fusion acts as a driver mutation that constitutively activates EGR1, which is known to be involved in the p16 pathway. Overexpression of p16 is associated with malignancy and worse prognosis in multiple mesenchymal tumors. The authors sought to investigate p16 immunoexpression in association with malignancy and prognosis of SFT/HPC tumors. Design Twenty-three SFT/HPC tumors (central nervous system [CNS]: 12, non CNS: 11) diagnosed at our institution from 2002 to 2016 were assigned into 3 grades. Data from microarray immunohistochemistry for STAT6, synaptophysin, CD56, chromogranin, SST2A, EGR1, Ki67, and p16, grade and survival were analyzed. Results CNS SFT/HPCs tend to be malignant (grade 3; 67 vs. 18%, p = 0.036) and more likely to express synaptophysin (33 vs. 0%, p = 0.035) than non CNS tumors. Overexpression of p16 (immunopositivity ≥ 50% tumor cells) was associated with malignant (grade 3) tumors, and has a sensitivity of 70% (7/10), and a specificity of 77% (10/13), as a predictive marker for malignancy. SFT/HPC patients with low p16 expression demonstrated significantly longer disease-free survival time (median survival > 113 months) than those with high p16 expression (median survival = 30 months, p = 0.045). Conclusions SFT/HPCs in the CNS are more likely to be malignant than the tumors in other sites. High p16 expression is also associated with malignancy and shorter disease-free survival time in SFT/HPC tumors in our study cohort. Clinically, p16 overexpression can be used as predictive marker for malignancy and prognosis and a possible therapeutic target.
Collapse
|
8
|
Chiasmal damage shown by optical coherence tomography: case illustration. J Neurosurg 2018; 130:2032-2033. [PMID: 29882699 DOI: 10.3171/2018.1.jns171915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 01/16/2018] [Indexed: 11/06/2022]
|
9
|
Commentary: An Introduction to Leadership Self-Assessment at the Society of Neurological Surgeons Post-Graduate Year 1 Boot Camp: Observations and Commentary. Neurosurgery 2017; 80:E201-E204. [DOI: 10.1093/neuros/nyw093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 12/01/2016] [Indexed: 11/14/2022] Open
|
10
|
Prevalence and predictors of loss to follow-up in young adults with mild haemophilia. Haemophilia 2016; 23:e36-e39. [PMID: 27928848 DOI: 10.1111/hae.13114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/12/2016] [Indexed: 11/29/2022]
|
11
|
Abstract
Using restriction fragment length polymorphism (RFLP) analysis, we demonstrated in 4 of 20 patients with astrocytomas loss of heterozygosity on the short arm of chromosome 17 (17p), in the telomeric segment distal to DNA marker pEW301 (locus D17S58). The loss of heterozygosity may uncover a mutation in a tumour suppressor gene and thus lead to or permit tumour formation. The p53 tumour suppressor gene, which is localized at 17p13, is a likely candidate for the tumour suppressor gene involved. Of the 4 patients with loss of heterozygosity on 17p, one patient had a grade I astrocytoma, another patient had a grade II astrocytoma and 2 patients had glioblastoma multiforme. Since the loss of heterozygosity on 17p was detected in low-grade as well as in high-grade astrocytomas, it is possible that p53 suppressor gene loss may be an early genetic event in the multistep process of astrocytoma formation.
Collapse
|
12
|
Survival following Ommaya reservoir placement for neoplastic meningitis. J Clin Neurosci 2015; 22:1467-72. [PMID: 26115896 DOI: 10.1016/j.jocn.2015.04.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2015] [Accepted: 04/05/2015] [Indexed: 11/25/2022]
Abstract
The objective of this study was to evaluate the outcomes of patients with neoplastic meningitis (NM) following Ommaya reservoir placement in order to determine whether any patient factors are associated with longer survival. NM is a devastating late manifestation of cancer, and given its dismal prognosis, identifying appropriate patients for Ommaya reservoir placement is difficult. The authors performed a retrospective review of 80 patients who underwent Ommaya reservoir placement at three medical centers from September 2001 through September 2012. The primary outcome was death. Differences in survival were assessed with Kaplan-Meier survival analyses. The Cox proportional hazards and logistic regression modeling were performed to identify factors associated with survival. The primary diagnoses were solid organ, hematologic, and primary central nervous system tumors in 53.8%, 41.3%, and 5%, respectively. The median overall survival was 72.5 days (95% confidence interval 36-122) with 30% expiring within 30 days and only 13.8% surviving more than 1 year. There were no differences in median overall survival between sites (p=0.37) despite differences in time from diagnosis of NM to Ommaya reservoir placement (p<0.001). Diagnosis of hematologic malignancy was inversely associated with death within 90 days (p=0.04; odds ratio 0.34), older age was associated with death within 90 days (p=0.05; odds ratio 1.5, per 10 year increase in age). The prognosis of NM remains poor despite the available treatment with intraventricular chemotherapy. There exists significant variability in treatment algorithms among medical centers and consideration of this variability is crucial when interpreting existing series of Ommaya reservoir use in the treatment of patients with NM.
Collapse
|
13
|
Use of cone-beam computed tomography angiography in planning for gamma knife radiosurgery for arteriovenous malformations: a case series and early report. Neurosurgery 2015; 74:682-95; discussion 695-6. [PMID: 24584136 DOI: 10.1227/neu.0000000000000331] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The effectiveness of Gamma Knife radiosurgery (GKR) for cerebral arteriovenous malformations (AVMs) is predicated on inclusion of the entire nidus while excluding normal tissue. As such, GKR may be limited by the resolution and accuracy of the imaging modality used in targeting. OBJECTIVE We present the first case series to demonstrate the feasibility of using ultrahigh-resolution C-arm cone-beam computed tomography angiography (CBCT-A) in AVM targeting. METHODS From June 2009 to June 2013, CBCT-A was used for targeting of all patients with AVMs treated with GKR at our institution. Patients underwent Leksell stereotactic head frame placement followed by catheter-based biplane 2-dimensional digital subtraction angiography, 3-dimensional rotational angiography, as well as CBCT-A. The CBCT-A dataset was used for stereotactic planning for GKR. Patients were followed at 1, 3, 6, and 12 months and then annually thereafter. RESULTS CBCT-A-based targeting was used in 22 consecutive patients. CBCT-A provided detailed spatial resolution and sensitivity of nidal angioarchitecture enabling treatment. The average radiation dose to the margin of the AVM nidus corresponding to the 50% isodose line was 15.6 Gy. No patient had treatment-associated hemorrhage. At early follow-up (mean, 16 months), 84% of patients had a decreasing or obliterated AVM nidus. CONCLUSION CBCT-A-guided radiosurgery is feasible and useful because it provides sufficient detailed resolution and sensitivity for imaging brain AVMs.
Collapse
|
14
|
Salvage Gamma Knife Radiosurgery after failed management of bilateral trigeminal neuralgia. Surg Neurol Int 2014; 5:160. [PMID: 25525553 PMCID: PMC4258705 DOI: 10.4103/2152-7806.145201] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 08/13/2014] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND The incidence of bilateral trigeminal neuralgia (TN) is 1-6% of total number of TN cases. Gamma Knife Radiosurgery (GKRS) is effective in treating unilateral TN; however, outcomes of bilateral TN treated by GKRS have not been well evaluated. The purpose of this study is to evaluate the long-term GKRS outcomes of bilateral TN at our institution and compare with our published treatment outcomes of unilateral TN. METHODS Between 2000 and 2006, eight patients with bilateral TN were treated with GKRS. Data available on seven patients were collected. Facial pain outcomes were defined using the Barrow Neurological Institute pain intensity scale. Outcomes and toxicities were compared to published outcomes of unilateral TN patients treated with GKRS at our institution. RESULTS The incidence of bilateral TN in our series is 2.3%. Treatment outcomes were excellent in 5/14, good in 1/14, and poor in 8/14. Median follow-up time was 58 months. Median time-to-failure was 38 months. Pain control rate was 80% at 12 months and 65% at 36 months. Bothersome side effects were seen in 4/14 nerves treated. Compared with our long-term unilateral TN cohort, there was no statistically significant difference in outcome, time-to-failure, or rate of toxicity. CONCLUSION Bilateral TN is rare, and effective treatment is crucial to improve the quality of life of those afflicted. Salvage GKRS is a reasonable treatment modality for individuals with bilateral TN.
Collapse
|
15
|
Molecular characterization of a 4,409,480 bp deletion of the human X chromosome in a patient with haemophilia B. Haemophilia 2014; 20:e230-4. [PMID: 24589221 DOI: 10.1111/hae.12395] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/24/2014] [Indexed: 11/26/2022]
|
16
|
Local Control and Results of Leksell Gamma Knife Therapy for the Treatment of Uveal Melanoma. Ophthalmic Surg Lasers Imaging Retina 2014; 45:125-31. [DOI: 10.3928/23258160-20140306-05] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 11/21/2013] [Indexed: 11/20/2022]
|
17
|
Mild elevations of international normalized ratio at hospital Day 1 and risk of expansion in warfarin-associated subdural hematomas. J Neurosurg 2013; 119:1050-7. [PMID: 23581582 DOI: 10.3171/2013.3.jns121946] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT A primary goal in the treatment of patients with warfarin-associated subdural hematoma (SDH) is reversal of coagulopathy with fresh-frozen plasma. Achieving the traditional target international normalized ratio (INR) of 1.3 is often difficult and may expose patients to risks of volume overload and of thromboembolic complications. This retrospective study evaluates the risk of mild elevations of INR from 1.31 to 1.69 at 24 hours after admission in patients presenting with warfarin-associated SDH. METHODS Sixty-nine patients with warfarin-associated SDH and 197 patients with non-warfarin-associated SDH treated at a single institution between January 2005 and January 2012 were retrospectively identified. Charts were reviewed for patient age, history of trauma, associated injuries, neurological status at presentation, size and chronicity of SDH, associated midline shift, INR at admission and at hospital Day 1 (HD1), concomitant aspirin or Plavix use, platelet count, and medical comorbidities. Patients were stratified according to use of warfarin and by INR at HD1 (INR 0.8-1.3, 1.31-1.69, 1.7-1.99, and ≥ 2). The groups were evaluated for differences the in rate of radiographic expansion of SDH and in the rate of clinically significant SDH expansion resulting in death, unplanned procedure, and/or readmission. RESULTS There was no difference in the rate of radiographic versus clinically significant expansion of SDH between patients not on warfarin and those on warfarin (no warfarin: 22.3% vs 20.3%, p = 0.866; warfarin: 10.7% vs 11.6%, p = 0.825), but the rate of medical complications was significantly higher in the warfarin subgroup (13.3% for patients who did not receive warfarin vs 26.1% for those who did; p = 0.023). For warfarin-associated SDH, there was no difference in the rate of radiographic versus clinically significant expansion between patients reversed to HD1 INRs of 0.8-1.3 and 1.31-1.69 (HD1 INR 0.8-1.3: 22.5% vs 20%, p = 1; HD1 INR 1.31-1.69: 15% vs 10%, p = 0.71). CONCLUSIONS Mild INR elevations of 1.31-1.69 in warfarin-associated SDH are not associated with a markedly increased risk of radiographic or clinically significant expansion of SDH. Larger prospective studies are needed to determine if subtherapeutic INR elevations at HD1 are associated with smaller increases in risk of SDH expansion.
Collapse
|
18
|
A national fundamentals curriculum for neurosurgery PGY1 residents: the 2010 Society of Neurological Surgeons boot camp courses. Neurosurgery 2012; 70:971-81; discussion 981. [PMID: 22015813 DOI: 10.1227/neu.0b013e31823d7a45] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND In July 2009, the Accreditation Council for Graduate Medical Education (ACGME) incorporated postgraduate year 1 (PGY1 intern) level training into all U.S. neurosurgery residency programs. OBJECTIVE To provide a fundamentals curriculum for all incoming neurosurgery PGY1 residents in ACGME-accredited programs, including skills, knowledge, and attitudes that promote quality, patient safety, and professionalism. METHODS The Society of Neurological Surgeons organized 6 regional "boot camp" courses for incoming neurosurgery PGY1 residents in July 2010 that consisted of 9 lectures on clinical and nonclinical competencies plus 10 procedural and 6 surgical skills stations. Resident and faculty participants were surveyed to assess knowledge and course effectiveness. RESULTS A total of 186 of 197 U.S. neurosurgical PGY1 residents (94%) and 75 neurosurgical faculty from 36 of 99 programs (36%) participated in the inaugural boot camp courses. All residents and 83% of faculty participants completed course surveys. All resident and faculty respondents thought that the boot camp courses fulfilled their purpose and objectives and imparted skills and knowledge that would improve patient care. PGY1 residents' knowledge of information taught in the courses improved significantly in postcourse testing (P < .0001). Residents and faculty particularly valued simulated and other hands-on skills training. CONCLUSION Regional organization facilitated an unprecedented degree of participation in a national fundamental skills program for entering neurosurgery residents. One hundred percent of resident and faculty respondents positively reviewed the courses. The boot camp courses may provide a model for enhanced learning, professionalism, and safety at the inception of training in other procedural specialties.
Collapse
|
19
|
Magnetic resonance imaging appearance and changes on intracavitary Gliadel wafer placement: A pilot study. World J Radiol 2011; 3:266-72. [PMID: 22132297 PMCID: PMC3226960 DOI: 10.4329/wjr.v3.i11.266] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Revised: 09/08/2011] [Accepted: 09/15/2011] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate changes on magnetic resonance imaging (MRI) which occur with intracavitary Gliadel wafer placement in patients with glioblastoma multiforme (GBM).
METHODS: This retrospective Health Insurance Portability and Accountability Act-compliant study was approved by the institutional review board, with a waiver of informed consent. A total of eight patients aged 29-67 years with GBM underwent Gliadel wafer placement. T2-weighted/FLAIR images and post-contrast T1-weighted images both before and after wafer placement were retrospectively reviewed in consensus to determine changes in the following parameters: appearance of the pericavitary tissue, pattern of tumor recurrence or progression and appearance of the Gliadel wafer itself.
RESULTS: Five out of the eight patients had a progressive increase in enhancement and pericavitary T2/ FLAIR hyperintensity within the first 2 mo and a subsequent decrease in these MRI findings. None of these patients had tumor recurrence within the first 6 mo. Three out of the eight patients demonstrated a progressive increase in enhancement and pericavitary T2 hyperintensity, which continued after the first 6 mo, and were subsequently diagnosed with true tumor progression. There was no increase in distant/nonlocal tumor recurrence. The Gliadel wafer appearance changed over time.
CONCLUSION: Pseudoprogression is common after intracavitary Gliadel wafer placement and thus care should be taken before diagnosing tumor progression or recurrence within the first 2 mo.
Collapse
|
20
|
Intraoperative use of indocyanine green fluorescence videography for resection of a spinal cord hemangioblastoma. Neurosurgery 2010; 67:ons300-3; discussion ons303. [PMID: 20679920 DOI: 10.1227/01.neu.0000383876.72704.7b] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND AND IMPORTANCE Indocyanine green (ICG) fluorescence videography has been recently applied to the neurosurgical field, mostly in the management of cerebral aneurysms, but has had limited description in the subspecialty of spine or oncological neurosurgery. We describe a novel application of this previously defined surgical tool to assist in the resection of a residual spinal cord hemangioblastoma. CLINICAL PRESENTATION Our patient is a 49-year-old woman with a residual symptomatic cervical hemangioblastoma that was previously embolized and resected at another institution. After initial symptomatic improvement, she returned with progressive symptoms, increasing radiographic spinal cord edema, and a residual lesion at the level of C1. We resected the remaining tumor with the adjuvant use of ICG fluorescence videography. Intraoperative injection of ICG clearly identified a component of the tumor underlying adhesive, opaque arachnoid that was not visualized by direct microscopy. Immediate postresection ICG videography suggested a complete resection was achieved which was later corroborated by postoperative magnetic resonance imaging. CONCLUSION The adjuvant use of ICG videography is a useful surgical tool that permits greater visualization of the complete extent of the lesion, particularly in managing recurrent or residual lesions obscured by adhesions.
Collapse
|
21
|
|
22
|
Multifocal Stevens-Johnson syndrome after concurrent phenytoin and cranial and thoracic radiation treatment, a case report. Radiat Oncol 2010; 5:49. [PMID: 20525360 PMCID: PMC2894848 DOI: 10.1186/1748-717x-5-49] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2009] [Accepted: 06/04/2010] [Indexed: 12/02/2022] Open
Abstract
A 46 year old male patient with metastatic prostate cancer developed Stevens-Johnson syndrome (SJS), initially in three well-demarcated areas on his scalp, chest and back, corresponding to ports of radiation therapy while on phenytoin. The rash spread from these locations and became more generalized and associated with pain and sloughing in the mucous lining of the mouth. There is a documented association between phenytoin administration with concurrent cranial radiation therapy and development of SJS. Erythema multiforme (EM) associated with phenytoin and cranial radiation therapy (EMPACT) is the term that describes this reaction. However, this term may not cover the full spectrum of the disease since it describes EM associated with phenytoin and only cranial radiation therapy. This case report presents evidence that SJS may be induced by radiation to other parts of the body in addition to the cranium while phenytoin is administered concomitantly. With increasing evidence that phenytoin and levetiracetam are equally efficacious for seizure treatment and prophylaxis, and since there is no link identified so far of an association between levetiracetam and SJS, we believe that levetiracetam is a better option for patients who need anticonvulsant medication(s) while undergoing radiation therapy, especially cranial irradiation.
Collapse
|
23
|
Outcomes following single-treatment Gamma Knife surgery for trigeminal neuralgia with a minimum 3-year follow-up. J Neurosurg 2010; 112:766-71. [PMID: 19780644 DOI: 10.3171/2009.8.jns081706] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Gamma Knife surgery (GKS) has been shown to be effective in treating trigeminal neuralgia (TN). Existing studies have demonstrated success rates of 69.1–85% with median follow-up intervals of 19–60 months. However, series with uniform long-term follow-up data for all patients have been lacking. In the present study the authors examined outcomes in a series of patients with TN who underwent a single GKS treatment followed by a minimum follow-up of 36 months. They used a clinical scale that simplifies the reporting of outcome data for patients with TN.
Methods
Fifty-three consecutive patients with typical, intractable TN received a median maximum radiation dose of 80 Gy applied with a single 4-mm isocenter to the affected trigeminal nerve. Follow-up data were obtained by clinical examination and questionnaire. Outcome results were categorized into the following classes (in order of decreasing success): Class 1A, complete pain relief without medications; 1B, complete pain relief with either a decrease or no change in medications; 1C, ≥ 50% pain relief without medications; 1D, ≥ 50% pain relief with either a decrease or no change in medications; and Class 2, < 50% pain relief and/or increase in medications. Patients with Class 1A–1D outcome (equivalent to Barrow Neurological Institute Grades I–IIIb) were considered to have a good treatment outcome, whereas in patients with Class 2 outcome (equivalent to Barrow Neurological Institute Grades IV and V) treatment was considered to have failed.
Results
A good treatment outcome from initial GKS was achieved in 31 (58.5%) patients for whom the mean follow-up period was 48 months (range 36–66 months). Outcomes at last follow-up were reflected by class status: Class 1A, 32.1% of patients; 1B, 1.9%; 1C, 3.8%; 1D, 20.8%; and Class 2, 41.5%. Statistical analysis showed no difference in outcomes between patients previously treated with microvascular decompression or rhizotomy compared with patients with no previous surgical treatments. Thirty-six percent of patients reported some degree of posttreatment facial numbness. Anesthesia dolorosa did not develop in any patient.
Conclusions
Despite a time-dependent deterioration in the success rate of GKS for medically intractable TN, the authors' study showed that > 50% of patients can be expected to have a good outcome based on their scoring system, with ~ 33% having an ideal outcome (pain free with no need for medications). Long-term data, as those presented here, are important when counseling patients on their treatment options.
Collapse
|
24
|
STAT3 is required for proliferation and maintenance of multipotency in glioblastoma stem cells. Stem Cells 2010; 27:2383-92. [PMID: 19658181 DOI: 10.1002/stem.185] [Citation(s) in RCA: 350] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Signal transducer and activator of transcription 3 (STAT3) regulates diverse cellular processes, including cell growth, differentiation, and apoptosis, and is frequently activated during tumorigenesis. Recently, putative glioblastoma stem cells (GBM-SCs) were isolated and characterized. These cells can self-renew indefinitely in culture, are highly tumorigenic, and retain the ability to differentiate in culture. We have found that treatment of GBM-SCs with two chemically distinct small molecule inhibitors of STAT3 DNA-binding inhibits cell proliferation and the formation of new neurospheres from single cells. Genetic knockdown of STAT3 using a short hairpin RNA also inhibits GBM-SC proliferation and neurosphere formation, confirming that these effects are specific to STAT3. Although STAT3 inhibition can induce apoptosis in serum-derived GBM cell lines, this effect was not observed in GBM-SCs grown in stem cell medium. Markers of neural stem cell multipotency also decrease upon STAT3 inhibition, suggesting that STAT3 is required for maintenance of the stem-like characteristics of these cells. Strikingly, even a transient inhibition of STAT3 leads to irreversible growth arrest and inhibition of neurosphere formation. These data suggest that STAT3 regulates the growth and self-renewal of GBM-SCs and is thus a potential target for cancer stem cell-directed therapy of glioblastoma multiforme.
Collapse
|
25
|
Dose De-Escalation With Gamma Knife Radiosurgery in the Treatment of Choroidal Melanoma. Int J Radiat Oncol Biol Phys 2009; 75:170-6. [DOI: 10.1016/j.ijrobp.2008.10.077] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Revised: 10/10/2008] [Accepted: 10/24/2008] [Indexed: 11/24/2022]
|
26
|
Retreatment of trigeminal neuralgia with Gamma Knife radiosurgery: is there an appropriate cumulative dose? J Neurosurg 2009; 111:359-64. [DOI: 10.3171/2008.11.jns08770] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Trigeminal neuralgia (TN) is a disorder of the trigeminal nerve that results in intense episodic pain. Primary treatment with Gamma Knife surgery (GKS) is well established; however, a significant number of patients experience recurrence of TN over time. Repeat GKS can be performed, but the retreatment dose has not been well established. In this study, the authors present their institutional retreatment results and compare them with other series.
Methods
Between December 2003 and January 2006, 28 patients were treated at Tufts Medical Center with repeat GKS for recurrence of TN. All patients had been initially treated with GKS at this institution, and only those with significant pain improvement were offered retreatment. The maximum dose was prescribed using a single isocenter; the 4-mm collimator was used. The initial median GKS dose was 80 Gy, the median retreatment dose was 45 Gy, and the median cumulative dose was 125 Gy. The median time between GKS procedures was 18.1 months. Facial pain outcomes were defined using the Marseille scale. Excellent outcome was defined as no pain (with or without medications), and good outcome was defined as > 50% pain relief. Toxicity was categorized as none, mild, or bothersome. The median clinical follow-up after the second GKS was 19.7 months. Our clinical outcomes were compared with 8 previously reported retreatment series (including 1 abstract), both for rate of pain control and for rate of complications.
Results
Outcomes after the second GKS were excellent in 29% (8 patients), good in 32% (9), and poor in 39% (11). Four patients (14%) experienced no improvement after repeat GKS. Eight patients (29%) experienced new trigeminal nerve dysfunction, including numbness (11%), paresthesia (14%), dysesthesia (4%), taste alteration (11%), and bite weakness (4%). None of these were bothersome. No patient developed corneal numbness. Univariate analysis failed to reveal any significant predictors of pain control or complications.
Seven published peer-reviewed retreatment series and the authors' data (total 215 patients) were analyzed. There was a cumulative dose-response relationship for both pain control (p = 0.04) and new trigeminal dysfunction (p = 0.08). Successful pain control was strongly correlated with development of new dysfunction (p = 0.02). A cumulative dose > 130 Gy was more likely to result in successful (> 50%) pain control, but was also more likely (> 20%) to result in development of new dysfunction.
Conclusions
Successful retreatment of patients in whom the initial GKS treatment fails is feasible. Patients who respond initially may be at a higher risk of retreatment-related complications. There appears to be a dose-response relationship for both pain control and development of new side effects. It is important to counsel and treat patients individually based on this dose-response relationship.
Collapse
|
27
|
Convexity dural cavernous malformation with intradural and extradural extension mimicking a meningioma: a case report. Acta Neurochir (Wien) 2009; 151:79-83. [PMID: 19096756 DOI: 10.1007/s00701-008-0175-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2008] [Accepted: 11/05/2008] [Indexed: 10/21/2022]
Abstract
BACKGROUND Dural-based cavernous malformations are rare and have been more commonly described in the middle fossa. Fewer than 20 cases outside of the middle fossa have been reported and they often mimic more commonly found lesions such as meningiomas or hemangiopericytomas. CASE DESCRIPTION We describe the unusual case of a right frontal convexity dural cavernous malformation with intradural and extradural components as well as erosion through the calvarium. The patient underwent a right frontal craniotomy and en-bloc resection of the mass. Final pathologic interpretation confirmed a cavernous malformation that had eroded through the calvarium. CONCLUSION Dural-based cavernous malformations are a rare entity, but should be considered in the differential diagnosis of atypical appearing dural-based lesions and soft subgaleal masses. If atypical features are present, further radiographic investigations should be undertaken. To our knowledge, this is the only reported case of a dural-based cavernous malformation eroding through the calvarium and presenting initially as a soft scalp mass.
Collapse
|
28
|
Severe protein S deficiency resulting from two novel mutations in PROS1 presenting with a relatively mild clinical phenotype. J Thromb Haemost 2008; 6:1237-9. [PMID: 18485091 DOI: 10.1111/j.1538-7836.2008.03012.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
29
|
Gefitinib and high-dose fractionated radiotherapy for carcinomatous encephalitis from non-small cell lung carcinoma. Biologics 2007; 1:321-4. [PMID: 19707341 PMCID: PMC2721320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Carcinomatous encephalitis is a rapidly fatal form of metastasis caused by miliary spread of systemic cancer into the brain parenchyma. The diagnostic criteria and optimal treatment for this disease are not well defined. We report a patient with rapid neurologic deterioration from carcinomatous encephalitis from lung adenocarcinoma. She was treated with gefitinib and high-dose fractionated whole brain radiotherapy, and eventually improved neurologically and was discharged home on hospital day 48. Gefitinib and high-dose fractionated radiotherapy may have synergistic activity in patients with carcinomatous encephalitis from non-small cell lung cancer having favorable prognostic factors. More importantly, timely recognition of this disease and the use of large fraction radiation therapy are necessary to control rapid neurologic deterioration.
Collapse
|
30
|
Matrix metalloprotease-9 in cerebrospinal fluid correlates with disease activity in lymphomatous meningitis. ACTA ACUST UNITED AC 2007; 7:305-8. [PMID: 17324339 DOI: 10.3816/clm.2007.n.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
PURPOSE The detection of lymphoma cells in cerebrospinal fluid (CSF) as a means to diagnose lymphomatous meningitis is problematic due to its low sensitivity. We hypothesize that matrix metalloproteases (MMPs) would be important in lymphomatous meningitis because lymphoma cells may produce MMPs for brain invasion and angiogenesis. PATIENTS AND METHODS Twentynine samples of CSF collected longitudinally from 5 patients receiving treatments for primary or metastatic CNS lymphomas were retrospectively analyzed by zymography. Cerebrospinal fluid cytology was correlated with levels of total protein, glucose, MMP-2, MMP-9, activated MMP-9, and 130 kDa MMP. RESULTS Increased CSF white blood cells (65 +/- 32 cells/microL vs. 9 +/- 8 cells/microL; P = 0.03) and MMP-9 (12.108 +/- 2.675 vs. 9.359 +/- 1.936; P = 0.02) had a strong correlation with abnormal CSF cytology. In addition, we observed that activated MMP-9 would appear and disappear depending on disease activity. Although there was nearly a 4-fold increase of mean activated MMP-9 in CSF samples with abnormal cytology findings when compared with negative cytology findings, the correlation did not reach statistical significance (1.382 +/- 0.76 vs. 0.389 +/- 0.155; P = 0.17). CONCLUSION Matrix metalloprotease-9 correlated strongly with lymphomatous meningitis, but MMP-2, activated MMP-2, activated MMP-9, and 130-kDa MMP did not.
Collapse
|
31
|
Effect of ocular artifact removal in brain computer interface accuracy. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2004:4385-8. [PMID: 17271277 DOI: 10.1109/iembs.2004.1404220] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We report the effect of removing ocular artifacts on the performance of a word-processing application based on the event related potential P300. Various methods of removing artifacts have been reported. The efficiency of these algorithms are usually done by subjective visual comparisons. Noting that there is a direct correlation of artifact rectifying algorithms to the accuracy in a brain computer interface system's accuracy, we present this work as a means to compare different algorithms.
Collapse
|
32
|
Abstract
We describe the case of a spinal epidural haematoma in an infant with severe haemophilia A. Initial signs and symptoms were non-specific resulting in delay of the diagnosis and more definitive therapy. The patient eventually developed torticollis, acute flaccid paralysis of the upper extremities, and respiratory distress, prompting radiological examination of the spinal cord. The patient was treated with recombinant FactorVIII and laminectomy. Neurological recovery was complete 3 months following the event. We hypothesize that infants with haemophilia may be at higher risk for this rare complication because of their increasing mobility, frequent falls while cruising furniture, and lack of prophylactic factor replacement. Non-specific signs such as irritability without a focus should alert the clinician to this diagnostic possibility. Torticollis should prompt rapid radiological evaluation of the cervical spine with magnetic resonance imaging to avoid delay in diagnosis.
Collapse
|
33
|
Clotting factor concentrates given to prevent bleeding and bleeding-related complications in people with hemophilia A or B. Cochrane Database Syst Rev 2006:CD003429. [PMID: 16625581 DOI: 10.1002/14651858.cd003429.pub3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND People with severe hemophilia A or B, X-linked bleeding disorders due to decreased blood levels of coagulants, suffer recurrent bleeding into joints and soft tissues. Before clotting factor concentrates were available, most people with severe hemophilia developed crippling musculoskeletal deformities. Clotting factor concentrate prophylaxis aims to preserve joint function by converting severe hemophilia (factor VIII or IX less than 1%) into a clinically milder form of the disease. Prophylaxis has long been used in Sweden, but not universally adopted because of medical, psychosocial, and cost controversies. Use of clotting factor concentrates is the single largest predictor of cost in treating hemophilia. OBJECTIVES To determine the effectiveness of clotting factor concentrate prophylaxis in the management of people with hemophilia A or B. SEARCH STRATEGY We searched the Cystic Fibrosis and Genetic Disorders Group's Trials Register comprising references from comprehensive electronic database searches and handsearches of journals and abstract books. Reference lists of relevant articles were reviewed. Most recent search: November 2005. SELECTION CRITERIA Randomized controlled trials (RCTs) evaluating people with severe hemophilia A or B, receiving prophylactic clotting factor concentrates. DATA COLLECTION AND ANALYSIS Two authors independently reviewed studies for eligibility, assessed methodological quality and extracted data. MAIN RESULTS Twenty-nine studies were identified; four studies (including 37 participants) were eligible for inclusion. Three studies evaluated hemophilia A; one showed a decrease in frequency of joint bleeds with prophylaxis compared to placebo (non-physiological dose), with a rate difference (RD) -10.80 (95% confidence interval (CI) -16.33 to -5.27) bleeds per year. The remaining two studies evaluating hemophilia A compared two prophylaxis regimens, one study showed no difference in joint bleed frequency, RD -5.04 (95%CI -17.02 to 6.94) bleeds per year and another failed to demonstrate an advantage of factor VIII dosing based on individual pharmacokinetic data over the standard prophylaxis regimen with RD -0.14 (95% CI -1.34 to 1.05) bleeds per year. The fourth study evaluated hemophilia B and showed fewer joint bleeds with weekly (15 IU/kg) versus bi-weekly (7.5 IU/kg) prophylaxis, RD -3.30 (95% CI -5.50 to - 1.10) bleeds per year. AUTHORS' CONCLUSIONS There is insufficient evidence from randomised controlled trials to determine whether prophylactic clotting factor concentrates decrease bleeding and bleeding-related complications in hemophilia A or B, compared to placebo, on-demand treatment, or prophylaxis based on pharmacokinetic data from individuals. Well-designed RCTs are needed to assess the effectiveness of prophylactic clotting factor concentrates. Two clinical trials are ongoing.
Collapse
|
34
|
The fibrinolytic system facilitates tumor cell migration across the blood-brain barrier in experimental melanoma brain metastasis. BMC Cancer 2006; 6:56. [PMID: 16524486 PMCID: PMC1421425 DOI: 10.1186/1471-2407-6-56] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2005] [Accepted: 03/09/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Patients with metastatic tumors to the brain have a very poor prognosis. Increased metastatic potential has been associated with the fibrinolytic system. We investigated the role of the fibrinolytic enzyme plasmin in tumor cell migration across brain endothelial cells and growth of brain metastases in an experimental metastatic melanoma model. METHODS Metastatic tumors to the brain were established by direct injection into the striatum or by intracarotid injection of B16F10 mouse melanoma cells in C57Bl mice. The role of plasminogen in the ability of human melanoma cells to cross a human blood-brain barrier model was studied on a transwell system. RESULTS Wild type mice treated with the plasmin inhibitor epsilon-aminocaproic acid (EACA) and plg-/- mice developed smaller tumors and survived longer than untreated wild type mice. Tumors metastasized to the brain of wild type mice treated with EACA and plg-/- less efficiently than in untreated wild type mice. No difference was observed in the tumor growth in any of the three groups of mice. Human melanoma cells were able to cross the human blood-brain barrier model in a plasmin dependent manner. CONCLUSION Plasmin facilitates the development of tumor metastasis to the brain. Inhibition of the fibrinolytic system could be considered as means to prevent tumor metastasis to the brain.
Collapse
|
35
|
Abstract
Brain metastases are an increasingly frequent and serious clinical problem for cancer patients, especially those with advanced melanoma. Given the extensive tropism of neural stem/progenitor cells (NSPCs) for pathological areas in the central nervous system, we expanded investigations to determine whether NSPCs could also target multiple sites of brain metastases in a syngeneic experimental melanoma model. Using cytosine deaminase-expressing NSPCs (CD-NSPCs) and systemic 5-fluorocytosine (5-FC) pro-drug administration, we explored their potential as a cell-based targeted drug delivery system to disseminated brain metastases. Our results indicate a strong tropism of NSPCs for intracerebral melanoma metastases. Furthermore, in our therapeutic paradigm, animals with established melanoma brain metastasis received intracranial implantation of CD-NSPCs followed by systemic 5-FC treatment, resulting in a significant (71%) reduction in tumor burden. These data provide proof of principle for the use of NSPCs for targeted delivery of therapeutic gene products to melanoma brain metastases.
Collapse
|
36
|
Clotting factor concentrates given to prevent bleeding and bleeding-related complications in people with hemophilia A or B. Cochrane Database Syst Rev 2005:CD003429. [PMID: 15846666 DOI: 10.1002/14651858.cd003429.pub2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND People with severe hemophilia A or B, X-linked bleeding disorders due to decreased blood levels of coagulants, suffer recurrent bleeding into joints and soft tissues. Before clotting factor concentrates were available, most people with severe hemophilia developed crippling musculoskeletal deformities. Clotting factor concentrate prophylaxis aims to preserve joint function by converting severe hemophilia (factor VIII or IX less than 1%) into a clinically milder form of the disease. Prophylaxis has long been used in Sweden, but not universally adopted because of medical, psychosocial, and cost controversies. Use of clotting factor concentrates is the single largest predictor of cost in treating hemophilia. OBJECTIVES To determine the effectiveness of clotting factor concentrate prophylaxis in the management of people with hemophilia A or B. SEARCH STRATEGY We searched the Cystic Fibrosis and Genetic Disorders Group's Trials Register comprising references from comprehensive electronic database searches and handsearches of journals and abstract books. Reference lists of relevant articles were reviewed. Most recent search: January 2002. SELECTION CRITERIA Randomized controlled trials (RCTs) evaluating people with severe hemophilia A or B, receiving prophylactic clotting factor concentrates. DATA COLLECTION AND ANALYSIS Two reviewers independently reviewed studies for eligibility, assessed methodological quality and extracted data. MAIN RESULTS Twenty-nine studies were identified, of which four (including 37 participants) were eligible for inclusion. Three studies evaluated hemophilia A; one showed a decrease in frequency of joint bleeds with prophylaxis compared to placebo (non-physiological dose), with a rate difference (RD) -10.80 (95% confidence interval (CI) -16.33 to -5.27) bleeds per year. The remaining two studies evaluating hemophilia A compared two prophylaxis regimens, one study showed no difference in joint bleed frequency, RD -5.04 (95%CI -17.02 to 6.94) bleeds per year and another failed to demonstrate an advantage of factor VIII dosing based on individual pharmacokinetic data over the standard prophylaxis regimen with RD -0.14 (95% CI -1.34 to 1.05) bleeds per year. The fourth study evaluated hemophilia B and showed fewer joint bleeds with weekly (15 IU/kg) versus bi-weekly (7.5 IU/kg) prophylaxis, RD -3.30 (95% CI -5.50 to - 1.10) bleeds per year. AUTHORS' CONCLUSIONS There is insufficient evidence to determine whether prophylactic clotting factor concentrates decrease bleeding and bleeding-related complications in hemophilia A or B, compared to placebo, on-demand treatment, or prophylaxis based on pharmacokinetic data from individuals. Well-designed RCTs are needed to assess the effectiveness of prophylactic clotting factor concentrates. Two clinical trials are ongoing.
Collapse
|
37
|
|
38
|
Abstract
BACKGROUND Methotrexate-based and alkylator-based chemotherapy regimens are associated with renal and bone marrow toxicities, which limit their use in patients with central nervous system (CNS) lymphomas. The authors report their experience with an immunochemotherapy regimen consisting of rituximab and temozolomide in patients with primary or metastatic CNS lymphoma. METHODS Seven patients who had received rituximab and temozolomide were identified from the database of the brain tumor clinic at the authors' institution: three patients had developed recurrent primary CNS lymphoma (PCNSL), one patient had newly diagnosed PCNSL but had poor renal function, and three other patients with systemic non-Hodgkin lymphoma developed recurrent lymphoma in the brain only. Patients were scheduled to receive 4 cycles of induction rituximab on Day 1 and temozolomide on Days 1-5 of a 28-day cycle. Thereafter, their treatment included a total of up to 8 maintenance cycles of temozolomide alone on Days 1-5 of a 28-day cycle. A gadolinium-enhanced magnetic resonance image of the head was obtained after every two cycles of treatment. RESULTS All patients received rituximab without toxicity. Of the 4 patients who received induction temozolomide at doses > 150 mg/m(2) daily on Days 1-5, 2 experienced Grade 2 leukopenia and thrombocytopenia. Five patients achieved a radiographic complete response, and two patients had partial responses after induction treatment. The median response duration was 6 months (range 3-12+ months), and the median survival was 8 months (range 3+-12+ months). CONCLUSIONS Although median survival was short, immunochemotherapy with rituximab and temozolomide was well tolerated and exhibited efficacy in this elderly and heavily pretreated cohort. The data obtained in the current study suggest that the optimal induction dose combination consists of rituximab 375 mg/m(2) on Day 1 and temozolomide 150 mg/m(2) daily on Days 1-5.
Collapse
|
39
|
Removal of arsenic from groundwater using point-of-use reverse osmosis and distilling devices. ENVIRONMENTAL TECHNOLOGY 2002; 23:781-790. [PMID: 12164638 DOI: 10.1080/09593332308618369] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Ground water in both the northeastern and southwestern coast areas of Taiwan may contain high concentrations of arsenic. Since no central water supply system is available in some of those areas, point-of-use (POU) water purification devices are considered as an option for providing safe drinking water. In this study, removal of arsenic, using two types of POU purification devices, reverse osmosis (RO) systems and distillers, was investigated. Three commercially available RO systems and two distillers were selected to test their removal efficiency of arsenic from synthetic and real ground water. Experimental results of the three RO systems using synthetic ground water showed that only one system had good removal efficiency for arsenic. In subsequent experiments using real ground water with 0.7 mg l(-1) arsenic, only one RO system was able to meet the drinking water standard after producing about 1,000 l of treated water. For the distilling systems, 99% of the arsenic was removed from both synthetic and real groundwater. The arsenic concentrations in the finished water of both distillers were all below the standard for drinking water. Although systems with higher arsenic removal efficiency seemed to have better removal of total dissolved solids (TDS), no correlation could be found after analysis.
Collapse
|
40
|
Characteristics of patients at a Taipei summer rock concert festival. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 2001; 64:525-30. [PMID: 11768283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
BACKGROUND Rock concerts are popular mass gatherings in Taiwan. Millions of fans participate in rock concerts in Taiwan each year. However, there were no reports on the characteristics of the patients seen in rock concerts in Taiwan. METHODS Medical care for a summer rock concert festival held in an outdoor stadium in Taipei was coordinated by emergency physicians of a medical center. About 50,000 attendees participated in the two-night concert. Three stations were set up to provide advanced medical care. A standardized form was used to collect information about patients. RESULTS A total of 28 cases visited the medical stations, fourteen cases each day. They were aged from 13 to 40 years, with an average of 20.8 +/- 6.4. Twenty-one cases were female and seven were male. Twenty-two (79%) were spectators, five (18%) were on-duty staff, and one was a by-stander. Based on an estimation of totally 50,000 participants in the stadium for this two-night festival, the medical use rate was roughly 5.6 PPTT (patients per ten thousand attendees). The most common major problem was fainting which accounted for 13 cases (46%). Of these 13 cases, three cases (23%) lost consciousness and 12 cases (92%) were female. Sixteen cases (57%) were classified as requiring ALS (advanced life support) and 12 cases (43%) as requiring BLS (basic life support). Most cases improved and were discharged after onsite treatment. Only one case was transferred by ambulance due to persistent chest pain. However, she recovered several hours later. CONCLUSIONS By this preliminary data, first reported in Taiwan, we found that the most common problem was fainting. More than half of the cases seen at the concert required advanced life support. A well-designed emergency medical service (EMS) system is mandatory to provide services for these events.
Collapse
|
41
|
Abstract
BACKGROUND Changes in the glycosylation process by tumor cells result in larger amounts of sialoproteins on their surface compared with normal cells. Sialoproteins then are released into the surrounding environment primarily by shedding or cell lysis. In the current study, the authors attempted to evaluate whether lipid-associated sialoprotein (LSP) in the cerebrospinal fluid (CSF) can distinguish patients with primary and metastatic brain tumors from those without brain tumors as well as determine response to treatment. METHODS CSF samples were obtained from a tissue bank. The concentration of LSP was determined after chloroform:methanol extraction followed by protein precipitation. One-way analysis of variance and Scheffe pairwise comparisons were used for statistical analysis. RESULTS The CSF of neurologically normal controls, patients with a normal leukocyte count (< or = 5/microl), and patients with various neurologic disorders or systemic tumors without central nervous system (CNS) malignancies contained similar levels of LSP. The CSF from patients with a normal leukocyte count and newly diagnosed primary or metastatic brain tumors contained on average 3.7-fold higher levels of LSP compared with CSF from patients without CNS tumors (P = 0.0001). The CSF from patients with brain tumors with progressive disease not responding to treatment contained high levels of LSP comparable to the levels found in newly diagnosed patients. The CSF from treatment-responsive patients contained decreased levels of LSP similar to that found in control patients. CONCLUSIONS The LSP in CSF may be a useful marker with which to determine the presence of intracranial malignancies and assess response to treatment.
Collapse
|
42
|
Adsorption of arsenite and arsenate within activated alumina grains: equilibrium and kinetics. WATER RESEARCH 2001; 35:2049-57. [PMID: 11337853 DOI: 10.1016/s0043-1354(00)00467-x] [Citation(s) in RCA: 245] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Equilibrium and kinetic adsorption of tri-valent (arsenite) and penta-valent (arsenate) arsenic to activated alumina is elucidated. The properties of activated alumina, including porosity, specific surface area, and skeleton density were first measured. A batch reactor with temperature control was employed to determine both adsorption capacity and adsorption kinetics for arsenite and arsenate to activated-alumina grains. The Freundlich and Langmuir isotherm equations were then used to describe the partitioning behavior for the system at different pH. A pore diffusion model, coupled with the observed Freundlich or Langmuir isotherm equations, was used to interpret an observed experimental adsorption kinetic curve for arsenite at one specific condition. The model was found to fit with the experimental data fairly well, and pore diffusion coefficients can be extracted. The model, incorporated with the interpreted pore diffusion coefficient, was then employed to predict the experimental data for arsenite and arsenate at various conditions, including different initial arsenic concentrations, grain sizes of activated alumina, and system pHs. The model predictions were found to describe the experimental data fairly well, even though the tested conditions substantially differed from one another. The agreement among the models and experimental data indicated that the adsorption and diffusion of arsenate and arsenite can be simulated by the proposed model.
Collapse
|
43
|
Abstract
Cells expressing herpes simplex-thymidine kinase (HSV-tk) can be killed "in vitro" within 5 days of treatment with 20 microM ganciclovir (GCV) and transmit this toxicity to adjacent cells lacking HSV-tk; this phenomenon was termed "bystander effect" or "kiss of death". On testing a large number of cell lines in vitro, a wide range of sensitivity to GCV-mediated bystander killing has been reported. Although intercellular transfer of GCV metabolites through gap junction channels seems to be a likely mechanism for the "kiss of death", some studies suggest that other pathways may contribute to induced apoptosis of neighboring cells. To further investigate the mechanism underlying cell death mediated by HSV-tk and to evaluate the efficacy of gap junction channels formed by different connexins in this process, we have stably transfected a virtually uncoupled mouse neuroblastoma cell line (N2A cells) with different connexin-types expressed by neural cells (Cx32, Cx37, Cx40, Cx43) and co-cultured these cells with N2A cells stably transfected with Cx37 and HSV-tk. Here, we confirm our previous studies and those of others that the extent of cell death and sensitivity to GCV depend on the degree of connexin expression in transfectants. Further, we show that the bystander effect also depends on which connexin is expressed; reported disparities regarding the extent of GCV-mediated cellular apoptosis are likely due both to the degree of functional coupling and the type of connexin expressed. These results support the notion that gap junction hemichannels formed of certain connexins are more likely than others to pair functionally with Cx37, and suggest co-transfection strategies that might prove effective in sensitizing tumor cell populations to GCV. In addition, potential applications are discussed for use of the "good Samaritan effect", a mechanism by which bystander cells have been suggested to prevent cytotoxicity.
Collapse
|
44
|
Inhibition of IMP-1 metallo-beta-lactamase and sensitization of IMP-1-producing bacteria by thioester derivatives. FEMS Microbiol Lett 1999; 179:289-96. [PMID: 10518728 DOI: 10.1111/j.1574-6968.1999.tb08740.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
IMP-1 metallo-beta-lactamase is a transferable carbapenem-hydrolyzing enzyme found in some clinical isolates of Pseudomonas aeruginosa, Serratia marcescens and Klebsiella pneumoniae. Bacteria that express IMP-1 show significantly reduced sensitivity to carbapenems and other beta-lactam antibiotics. A series of thioester derivatives has been shown to competitively inhibit purified IMP-1. As substrates for IMP-1, the thioesters yielded thiol hydrolysis products which themselves were reversible competitive inhibitors. The thioesters also increased sensitivity to the carbapenem L-742,728 in an IMP-1-producing laboratory stain of Escherichia coli, but will need further modification to improve their activity in less permeable organisms such as Pseudomonas and Serratia. Nonetheless, the thioester IMP-1 inhibitors offer an encouraging start to overcoming metallo-beta-lactamase-mediated resistance in bacteria.
Collapse
|
45
|
Clonal analysis of a case of multiple meningiomas using multiple molecular genetic approaches: pathology case report. Neurosurgery 1999; 45:409-16. [PMID: 10449091 DOI: 10.1097/00006123-199908000-00049] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE Multiple meningiomas are uncommon brain tumors occurring concurrently in several intracranial locations in the same patient. In the present study, we determined the clonality, methylation status of deoxyribonucleic acid, and relationship of genetic alterations in eight meningiomas from one female patient. METHODS Six molecular genetic techniques, including two methylation-based clonality assays and one transcription-based clonality assay, methylation analysis of CpG islands by methylation-specific polymerase chain reaction, loss of heterozygosity, microsatellite instability, and mutational analysis of the NF2 gene on chromosome 22, were used in comparative investigations on clonality and genetic alterations. RESULTS The presence of clonal tumor cells was demonstrated by 1) loss of the same copy of chromosome 22 in all eight tumors; 2) transcription of the human AR gene from the same allele in six of eight tumors; 3) a common unmethylated allele at the AR locus in all eight tumors; and 4) the identical single-basepair insertion mutation in exon 9 of the NF2 gene in six of eight tumors. In addition, loss of a copy of the X chromosome in one tumor nodule and microsatellite instability in another nodule were observed. CONCLUSION Taken together, this case of multiple meningiomas was most likely monoclonal in origin. Loss of chromosome 22 was an early event during the development of multiple meningiomas and was followed by mutations at the NF2 locus. Later events, including loss of the X chromosome, variation of AR gene expression, or microsatellite instability, may also have played a role in the development of multiple meningiomas in this patient.
Collapse
|
46
|
Noninvasive evaluation of blunt abdominal trauma: prospective study using diagnostic algorithms to minimize nontherapeutic laparotomy. World J Surg 1999; 23:265-69; discussion 269-70. [PMID: 9933698 DOI: 10.1007/pl00013178] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A prospective study was performed to investigate the feasibility and benefit of evaluating blunt abdominal trauma (BAT) without diagnostic peritoneal lavage (DPL) or other invasive methods. Diagnostic algorithms were designed by using ultrasonography (US) as a screening method. For unstable patients, a free fluid >/= 2 mm thickness on US images over any one of the intraperitoneal spaces (bilateral subphrenic, Morrison, and Douglas pouch) was used as an indicator for laparotomy. For stable patients, any intraabdominal free fluid detected by US was used as an indicator for further investigations. Computed tomography served as a principal complementary method. To further clarify the clinical results, the rate of nontherapeutic laparotomy (NTL) was compared with that from a previous 5-year review done before this study. During studying period of 1 year, 170 patients were consecutively enrolled. There was no delayed diagnosis, and 66 patients were found to have BAT; 17 patients were initial unstable, among whom 15 had free fluid shown by US and 13 patients had confirmed BAT. Eight of the unstable patients with free fluid on US were saved from NTL, of whom six had retroperitoneal hematoma. There was no NTL in unstable patients. Twenty-two patients underwent laparotomy. Two laparotomies done for a suspicion of bowel injury turned out to be NTL. The rate of NTL in the present study was significant lower than that in a previous review (9.1% vs. 32.2%, p = 0.025). Hence following well designed algorithms, noninvasive evaluation of BAT can proceed with safety, and NTL is minimized.
Collapse
|
47
|
Connexins are expressed in primary brain tumors and enhance the bystander effect in gene therapy. Neurosurgery 1999; 44:361-8; discussion 368-9. [PMID: 9932890 DOI: 10.1097/00006123-199902000-00068] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE Experimental brain tumor gene therapy with the herpes simplex virus thymidine kinase (HSV-tk) gene has demonstrated that not only HSV-tk transduced but surrounding non-HSV-tk transduced cells are killed when given ganciclovir. This so-called bystander effect has recently been shown to be dependent on connexin-mediated intercellular communication. To assess potential susceptibility to the bystander effect, we examined levels of connexin-26 and connexin-43 expression in a series of primary brain tumors. Connexin-26 expression has not previously been studied in primary brain tumors and connexin-43 expression has not been studied in nonastrocytic primary brain tumors. We also attempted to enhance the bystander effect in vitro by overexpressing connexin in tumor cells with high basal levels of connexin expression. METHODS Western blot analysis and immunohistochemistry were used to determine levels of connexin-26 and connexin-43 expression in a series of primary brain tumors. Wild-type 9L gliosarcoma cells were transfected in vitro with the connexin-43 gene and the HSV-tk gene or the HSV-tk gene alone. The bystander effect of each transfectant was then assessed and compared. RESULTS Most of the primary brain tumors tested, including low-grade astrocytomas, anaplastic astrocytomas, glioblastomas, oligodendrogliomas, gangliogliomas, meningiomas, and medulloblastomas, showed connexin-26 and connexin-43 expression. Bystander experiments revealed a significant enhancement of the bystander effect in the gliosarcoma cells transfected with connexin-43 and HSV-tk, as compared with gliosarcoma cells transfected with HSV-tk alone. CONCLUSION Most primary brain tumors express connexin-26 and connexin-43. This suggests that most primary brain tumors may be susceptible to the bystander effect of HSV-tk gene therapy. The bystander effect can be enhanced in vitro by overexpression of connexin-43 in a cell line with a high basal level of connexin-43 expression.
Collapse
|
48
|
A non-invasive immobilization system and related quality assurance for dynamic intensity modulated radiation therapy of intracranial and head and neck disease. Int J Radiat Oncol Biol Phys 1999; 43:455-67. [PMID: 10030275 DOI: 10.1016/s0360-3016(98)00398-8] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
PURPOSE To develop and implement a non-invasive immobilization system guided by a dedicated quality assurance (QA) program for dynamic intensity-modulated radiotherapy (IMRT) of intracranial and head and neck disease, with IMRT delivered using the NOMOS Corporation's Peacock System and MIMiC collimator. METHODS AND MATERIALS Thermoplastic face masks are combined with cradle-shaped polyurethane foaming agents and a dedicated quality assurance program to create a customized headholder system (CHS). Plastic shrinkage was studied to understand its effect on immobilization. Fiducial points for computerized tomography (CT) are obtained by placing multiple dabs of barium paste on mask surfaces at intersections of laser projections used for patient positioning. Fiducial lines are drawn on the cradle along laser projections aligned with nasal surfaces. Lateral CT topograms are annotated with a crosshair indicating the origin of the treatment planning and delivery coordinate system, and with lines delineating the projections of superior-inferior field borders of the linear accelerator's secondary collimators, or with those of the fully open MIMiC. Port films exposed with and without the MIMIC are compared to annotated topograms to measure positional variance (PV) in superior-inferior (SI), right-left (RL), and anterior posterior (AP) directions. MIMiC vane patterns superposed on port films are applied to verify planned patterns. A 12-patient study of PV was performed by analyzing positions of 10 anatomic points on repeat CT topograms, plotting histograms of PV, and determining average PV. RESULTS AND DISCUSSION A 1.5+/-0.3 mm SD shrinkage per 70 cm of thermoplastic was observed over 24 h. Average PV of 1.0+/-0.8, 1.2+/-1.1, and 1.3+/-0.8 mm were measured in SI, AP, and RL directions, respectively. Lateral port films exposed with and without the MIMiC showed PV of 0.2+/-1.3 and 0.8+/-2.2 mm in AP and SI directions. Vane patterns superimposed on port films consistently verified the planned patterns. CONCLUSION The CHS provided adequately reproducible immobilization for dynamic IMRT, and may be applicable to decrease PV for other cranial and head and neck external beam radiation therapy.
Collapse
|
49
|
Unanticipated inhibition of the metallo-beta-lactamase from Bacteroides fragilis by 4-morpholineethanesulfonic acid (MES): a crystallographic study at 1.85-A resolution. Biochemistry 1998; 37:6791-800. [PMID: 9578564 DOI: 10.1021/bi9730339] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
As part of a structure-aided effort to design clinically useful inhibitors of metallo-beta-lactamases, the X-ray crystal structure of a complex between the metallo-beta-lactamase from Bacteroides fragilis and 4-morpholinoethanesulfonic acid (MES) has been determined and a model for the structure has been refined to a crystallographic R-factor of 0.151 for data between 10.0- and 1.85-A resolution. Although the binding of MES was an adventitious result of the use of MES as a buffer in the crystallization mixture, MES was subsequently shown to be a competitive inhibitor of the enzyme, with a Ki of 23 +/- 5 mM. MES binds in the same fashion to both of the molecules in the crystallographic asymmetric unit; both direct and solvent-mediated hydrogen bonds to the protein and to the binuclear zinc cluster are observed, involving the oxygens of the sulfonic acid group and the nitrogen of the morpholino ring. In addition, there are hydrophobic interactions between the morpholino ring and residues in the flexible beta-strand of the enzyme between residues 26 and 36. Comparison of this structure with the previously reported unliganded structures of the same enzyme [Concha, N. O., Rasmussen, B. A., Bush, K., and Herzberg, O. (1996) Structure 4, 823-836; Carfi, A., Duée, E., Paul-Soto, R., Galleni, M., Frère, J. -M., and Dideberg, O. (1998) Acta Crystallogr. D54, 47-57] reveals that although the overall conservation of structure in the three different crystal lattices is very high, binding of MES is correlated with a significant change in the conformation of this beta-strand. The flexibility of this beta-strand will be an important consideration in the design of inhibitors of the metallo-beta-lactamases.
Collapse
|
50
|
Antibiotic sensitization using biphenyl tetrazoles as potent inhibitors of Bacteroides fragilis metallo-beta-lactamase. CHEMISTRY & BIOLOGY 1998; 5:185-96. [PMID: 9545432 DOI: 10.1016/s1074-5521(98)90632-9] [Citation(s) in RCA: 205] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND High level resistance to carbapenem antibiotics in gram negative bacteria such as Bacteroides fragilis is caused, in part, by expression of a wide-spectrum metallo-beta-lactamase that hydrolyzes the drug to an inactive form. Co-administration of metallo-beta-lactamase inhibitors to resistant bacteria is expected to restore the antibacterial activity of carbapenems. RESULTS Biphenyl tetrazoles (BPTs) are a structural class of potent competitive inhibitors of metallo-beta-lactamase identified through screening and predicted using molecular modeling of the enzyme structure. The X-ray crystal structure of the enzyme bound to the BPT L-159,061 shows that the tetrazole moiety of the inhibitor interacts directly with one of the two zinc atoms in the active site, replacing a metal-bound water molecule. Inhibition of metallo-beta-lactamase by BPTs in vitro correlates well with antibiotic sensitization of resistant B. fragilis. CONCLUSIONS BPT inhibitors can sensitize a resistant B. fragilis clinical isolate expressing metallo-beta-lactamase to the antibiotics imipenem or penicillin G but not to rifampicin.
Collapse
|