Murine roseolovirus does not accelerate amyloid-β pathology and human roseoloviruses are not over-represented in Alzheimer disease brains

BACKGROUND

The role of viral infection in Alzheimer Disease (AD) pathogenesis is an area of great interest in recent years. Several studies have suggested an association between the human roseoloviruses, HHV-6 and HHV-7, and AD. Amyloid-β (Aβ) plaques are a hallmark neuropathological finding of AD and were recently proposed to have an antimicrobial function in response to infection. Identifying a causative and mechanistic role of human roseoloviruses in AD has been confounded by limitations in performing in vivo studies. Recent -omics based approaches have demonstrated conflicting associations between human roseoloviruses and AD. Murine roseolovirus (MRV) is a natural murine pathogen that is highly-related to the human roseoloviruses, providing an opportunity to perform well-controlled studies of the impact of roseolovirus on Aβ deposition.

METHODS

We utilized the 5XFAD mouse model to test whether MRV induces Aβ deposition in vivo. We also evaluated viral load and neuropathogenesis of MRV infection. To evaluate Aβ interaction with MRV, we performed electron microscopy. RNA-sequencing of a cohort of AD brains compared to control was used to investigate the association between human roseolovirus and AD.

RESULTS

We found that 5XFAD mice were susceptible to MRV infection and developed neuroinflammation. Moreover, we demonstrated that Aβ interacts with viral particles in vitro and, subsequent to this interaction, can disrupt infection. Despite this, neither peripheral nor brain infection with MRV increased or accelerated Aβ plaque formation. Moreover, -omics based approaches have demonstrated conflicting associations between human roseoloviruses and AD. Our RNA-sequencing analysis of a cohort of AD brains compared to controls did not show an association between roseolovirus infection and AD.

CONCLUSION

Although MRV does infect the brain and cause transient neuroinflammation, our data do not support a role for murine or human roseoloviruses in the development of Aβ plaque formation and AD.

Leukocyte-dependent effects of platelet-rich plasma on cartilage loss and thermal hyperalgesia in a mouse model of post-traumatic osteoarthritis

OBJECTIVE

Platelet-rich plasma (PRP) is an emerging therapeutic strategy for treatment of osteoarthritis (OA); however, there is a lack of preclinical and clinical evidence for its efficacy and its mechanism of action is unclear. In the current study, we utilized leukocyte poor-PRP (LP-PRP) and leukocyte rich-PRP (LR-PRP) to mimic clinical point of care formulations and assessed their potential to alter disease progression in a mouse model of post-traumatic OA.

METHOD

Three-month-old wild-type male FVB/N mice received destabilization of the medial meniscus (DMM) surgery to induce OA. To assess the efficacy of LP-PRP and LR-PRP, mice were given intraarticular injections at 2-, 7- and 28-days post-surgery. Mice were then assessed at 5-, 9-, and 13-weeks post-surgery for changes in chronic pain using the hot plate nociceptive assay. At 14-weeks, OA pathogenesis was evaluated using histology and phase-contrast μCT.

RESULTS

Treatment with LP-PRP and to a lesser extent LR-PRP preserved cartilage volume and surface area compared to phosphate-buffered saline (PBS) as measured by phase-contrast μCT. However, both treatments had higher Osteoarthritis Research Society International (OARSI) and synovitis scores compared to sham, and neither substantially improved scores compared to PBS controls. With respect to thermal hyperalgesia, PBS-treated mice displayed reduced latency to response compared to sham, and LR-PRP but not LP-PRP improved latency to response at 5-, 9- and 13-weeks post-surgery compared to PBS.

CONCLUSION

The results of this study suggest that effects of PRP therapy on OA progression and disease-induced hyperalgesia may be leukocyte-dependent. And while LP-PRP and to a lesser extent LR-PRP protect from volume and surface loss, significant pathology is still seen within OA joints. Future work is needed to understand how the different components of PRP effect OA pathogenesis and pain, and how these could be modified to achieve greater therapeutic efficacy.

MGMT-inhibitor in combination with TGF-βRI inhibitor or CDK 4/6 inhibitor increases temozolomide sensitivity in temozolomide-resistant glioblastoma cells

BACKGROUND

Glioblastoma (GB) remains an incurable and deadly brain malignancy that often proves resistant to upfront treatment with temozolomide. Nevertheless, temozolomide remains the most commonly prescribed FDA-approved chemotherapy for GB. The DNA repair protein methylguanine-DNA methyl transferase (MGMT) confers resistance to temozolomide. Unsurprisingly temozolomide-resistant tumors tend to possess elevated MGMT protein levels or lack inhibitory MGMT promotor methylation. In this study, cultured human temozolomide resistance GB (43RG) cells were introduced to the MGMT inhibitor O⁶-benzylguanine combined with temozolomide and either LY2835219 (CDK 4/6 inhibitor) or LY2157299 (TGF-βRI inhibitor) seeking to overcome GB treatment resistance.

METHODS

Treatment effects were assessed using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, western blot, cell viability, and cell cycle progression.

RESULTS

Our in vitro study demonstrated that sequential treatment of O⁶-Benzylguanine with either LY2385219 or LY2157299-enhanced temozolomide enhanced sensitivity in MGMT+ 43RG cells. Importantly, normal human neurons and astrocytes remained impervious to the drug therapies under these conditions. Furthermore, LY2835219 has additional anti-proliferative effects on cell cycling, including induction of an RB-associated G (1) arrest via suppression of cyclin D-CDK4/6-Rb pathway. LY2157299 enhances anti-tumor effect by disrupting TGF-β-dependent HIF-1α signaling and by activating both Smad and PI3K-AKT pathways towards transcription of S/G2 checkpoints.

CONCLUSION

This study establishes the groundwork for the development of a combinatorial pharmacologic approach by using either LY2385219 or LY2157299 inhibitor plus O⁶-Benzylguanine to augment temozolomide response in temozolomide-resistant GB cells.

Evaluating anti-tumor activity of palbociclib plus radiation in anaplastic and radiation-induced meningiomas: pre-clinical investigations

PURPOSE

Meningiomas are common brain tumors, the majority of which are considered benign. Despite surgery and/or radiation therapy, recurrence rates are approximately 8-10%. One likely cause is the dysregulation of cyclin D-cyclin-dependent kinases 4 and 6 (CDK4/6)-retinoblastoma (Rb) pathway, which controls the cell cycle restriction point. This pathway is commonly dysregulated in anaplastic meningioma cell lines (AM) and radiation-induced meningioma cells (RIM), making it a rational target for anti-meningioma therapy. In this study, we investigate the effect of a CDK4/6 inhibitor, palbociclib, with radiation in relevant pre-clinical models.

METHODS

In vitro cell culture, ex vivo slice culture and in vivo cell line-derived orthotopic xenograft animal models of AM/RIM were utilized to assess treatment efficacy with palbociclib plus radiation. Treatment effects were examined by immunoblot, cell viability, apoptosis, and cell cycle progression.

RESULTS

The in vitro and ex vivo studies demonstrate that palbociclib plus radiation treatment reduced proliferation and has additional effects on cell cycling, including induction of an RB-associated G (1) arrest in Rb+ AM and RIM cells, but not in Rb- cells. Our results also demonstrated reduced CDK4 and CDK6 expression as well as reduced E2F target gene expression (CCNA2 and CCNE2) with the combination therapy. MRI results in vivo demonstrated reduced tumor size at 5 weeks when treated with 14 days palbociclib (10 mg/kg) plus 6 Gy radiation compared to saline-treated tumors. Finally, no hepatic toxicity was found after treatments.

CONCLUSION

A pre-clinical murine model provides preclinical evidence for use of palbociclib plus radiation as a therapeutic agent for Rb+ meningiomas.

Ganoderic acid A/DM-induced NDRG2 over-expression suppresses high-grade meningioma growth

PURPOSE

N-myc downstream-regulated gene 2 (NDRG2) is down-regulated in grade-III meningioma [anaplastic meningioma (AM)] and associated with clinically aggressive behavior. Current therapies in the treatment of high-grade meningioma are lacking with limited success. This study aims to validate the effect of NDRG2-targeted therapy using structurally related bioactive triterpene compounds derived from the edible mushroom Ganoderma lucidum (ganoderic acid A:GA-A/ganoderic acid DM:GA-DM) in human AM in relevant pre-clinical models.

METHODS

Tissue samples from the AM tumor regions of three human patients and control non-tumor samples were used to analyze the expression pattern of NDRG2. In vitro cell culture and in vivo cell-line-derived orthotopic xenograft animal models of AM were utilized to assess efficacy of treatment with GA-A/DM.

RESULTS

Downregulation of NDRG2 expression was observed in surgically resected high-grade meningiomas compared to normal brain. These results prompt us to use NDRG2-targeting agents GA-A/DM. In vitro results showed that 72-h treatments of 25 µM GA-A/DM induced AM cell death, upregulate NDRG2 protein expression, downregulate NDRG2 promoter methylation in meningioma cells as compared to azacitidine and decitabine, the most commonly used demethylating agents. Our results also demonstrated that GA-A/DM does not have any detrimental effect on normal human neurons and arachnoid cells. GA-A/DM promoted apoptotic factors (Bax) while suppressing MMP-9, p-P13K, p-AKT, p-mTOR, and Wnt-2 protein expression. RNAi-mediated knockdown of NDRG2 protein expression increased tumor proliferation, while forced expression of wt-NDRG2 decreased proliferation in an in vitro model. Magnetic resonance (MR) imaging and Hematoxylin (H&E) staining demonstrated gross reduction of tumor volume in GA-A/DM treated mice at 5 weeks when compared with saline-treated orthotopic AM xenografted controls. There was an overall decrease in tumor cell proliferation with increased survival in GA-A/DM-treated animals. Enzyme assays showed that GA-A/DM did not negatively impact hepatic function.

CONCLUSION

GA-A/DM may be a promising natural therapeutic reagent in the treatment of AM by suppressing growth via NDRG2 modulation and altering of intracellular signal pathways. We have shown it could potentially be an effective treatment for AM with decreased cellular proliferation in vitro, decreased tumor volume and increased survival in vivo.

The efficacy of unilateral laparoscopic nephrectomy in the pediatric hypertensive patient

BACKGROUND

Secondary hypertension due to a poorly functioning or non-functional kidney may be refractory to medical management. In such cases, nephrectomy can improve or cure hypertension. With the routine use of laparoscopy, nephrectomy can be performed in a minimally invasive manner, but surgery still carries inherent risks and complications.

OBJECTIVE

The objective of this study is to evaluate the outcomes of laparoscopic nephrectomy performed for secondary hypertension and identify potential predictors of postoperative hypertension resolution.

METHODS

After obtaining approval from institutional review board, patients from January 2002 to March 2018 who underwent laparoscopic nephrectomy were identified using Current Procedural Technology codes. All charts were then manually reviewed to isolate those patients with secondary hypertension present preoperatively. Patient demographics, urologic history, and laboratory and imaging findings were recorded for all patients. Serial blood pressures were recorded at all renal visits along with any antihypertensive medication changes. Postoperative outcomes and complications were also noted for all patients.

RESULTS

A total of 20 patients (7 girls, 13 boys) underwent laparoscopic nephrectomy to treat hypertension at an average age of 10.6 years (range 1.7-17.0 years). Etiology of a solitary non-functional kidney was vesicoureteral reflux in 10 of 20 patients, multicystic dysplastic kidney in 5 of 20, ureteropelvic junction obstruction in 2 of 20, ureteral obstruction in 1 of 20, and renal artery stenosis in 2 of 20 patients. At time of surgery, 3 of 20 patients were on two antihypertensives, 10 of 20 were on one antihypertensive, and 7 of 20 proceeded to surgery with no medical management. In the 30-day postoperative period, no complications were noted. Hypertension improved in 10 of 20 (50%) patients, all of whom were not on any antihypertensive medications after surgery. Hypertension persisted in 4 of 20 (20%) patients, requiring the same antihypertensive regimen and worsened in 6 of 20 (30%) patients, requiring increased doses and/or additional antihypertensives. Average follow-up time was 2.7 years. No significant predictors of postoperative hypertension result were identified when comparing the groups of responders and non-responders.

DISCUSSION

While laparoscopic nephrectomy for a non-functioning kidney in the setting of hypertension is a safe procedure, the cure rate for hypertension in the cohort appears to be on the low side of what was previously reported. While the small sample size is a main limitation, it is among the largest sample sizes for pediatric hypertensive patients. Previously shown predictors were not predictive in the similar-sized cohort.

CONCLUSIONS

Patients should be carefully counseled on the risks and benefits of nephrectomy to treat hypertension, the importance of continued follow-up after nephrectomy, and the possible need for chronic medical management with antihypertensives.

Cryptic activation of an Irf8 enhancer governs cDC1 fate specification

Induction of the transcription factor Irf8 in the common dendritic cell progenitor (CDP) is required for classical type 1 dendritic cell (cDC1) fate specification, but the mechanisms controlling this induction are unclear. In the present study Irf8 enhancers were identified via chromatin profiling of dendritic cells and CRISPR/Cas9 genome editing was used to assess their roles in Irf8 regulation. An enhancer 32 kilobases (kb) downstream of the Irf8 transcriptional start site (+32-kb Irf8) that was active in mature cDC1s was required for the development of this lineage, but not for its specification. Instead, a +41-kb Irf8 enhancer, previously thought to be active only in plasmacytoid dendritic cells, was found to also be transiently accessible in cDC1 progenitors, and deleting this enhancer prevented the induction of Irf8 in CDPs and abolished cDC1 specification. Thus, cryptic activation of the +41-kb Irf8 enhancer in dendritic cell progenitors is responsible for cDC1 fate specification.

First-Onset Herpesviral Infection and Lung Injury in Allogeneic Hematopoietic Cell Transplantation

Rationale: "Noninfectious" pulmonary complications are significant causes of morbidity and mortality after allogeneic hematopoietic cell transplant. Early-onset viral reactivations or infections are common after transplant. Whether the first-onset viral infection causes noninfectious pulmonary complications is unknown. Objectives: To determine whether the first-onset viral infection within 100 days after transplant predisposes to development of noninfectious pulmonary complications. Methods: We performed a retrospective review of 738 allogeneic hematopoietic cell transplant patients enrolled from 2005 to 2011. We also established a novel bone marrow transplantation mouse model to test whether herpesviral reactivation after transplant causes organ injury. Measurements and Main Results: First-onset viral infections with human herpesvirus 6 or Epstein-Barr virus within 100 days after transplant increase the risk of developing idiopathic pneumonia syndrome (adjusted hazard ratio [aHR], 5.52; 95% confidence interval [CI], 1.61-18.96; P = 0.007; and aHR, 9.21; 95% CI, 2.63-32.18; P = 0.001, respectively). First infection with human cytomegalovirus increases risk of bronchiolitis obliterans syndrome (aHR, 2.88; 95% CI, 1.50-5.55; P = 0.002) and grade II-IV acute graft-versus-host disease (aHR, 1.59; 95% CI, 1.06-2.39; P = 0.02). Murine roseolovirus, a homolog of human herpesvirus 6, can also be reactivated in the lung and other organs after bone marrow transplantation. Reactivation of murine roseolovirus induced an idiopathic pneumonia syndrome-like phenotype and aggravated acute graft-versus-host disease. Conclusions: First-onset herpesviral infection within 100 days after allogeneic hematopoietic cell transplant increases risk of pulmonary complications. Experimentally reactivating murine roseolovirus causes organ injury similar to phenotypes seen in human transplant recipients.

CD8+ T Cells Prevent Lethality from Neonatal Murine Roseolovirus Infection

A recently described mouse homolog of the human roseoloviruses, murine roseolovirus (MRV), causes loss of peripheral and thymic CD4⁺ cells during neonatal infection of BALB/c mice. Despite significant disruptions to the normal adaptive immune response, infected BALB/c mice reproducibly recover from infection, consistent with prior studies on a related virus, mouse thymic virus. In this article, we show that, in contrast to published studies on mouse thymic virus, MRV appears to robustly infect neonatal C57BL/6 (B6) mice, causing severe depletion of thymocytes and peripheral T cells. Moreover, B6 mice recovered from infection. We investigated the mechanism of thymocyte and T cell loss, determining that the major thymocyte subsets were infected with MRV; however, CD4⁺ and CD4⁺CD8^- T cells showed increased apoptosis during infection. We found that CD8⁺ T cells populated MRV-infected thymi. These CD8⁺ T cells expressed markers of activation, had restricted TCR repertoire, and accumulated intracellular effector proteins, consistent with a cytotoxic lymphocyte phenotype and suggesting their involvement in viral clearance. Indeed, absence of CD8⁺ T cells prevented recovery from MRV infection and led to lethality in infected animals, whereas B cell-deficient mice showed CD4⁺ T cell loss but recovered from infection without lethality. Thus, these results demonstrate that CD8⁺ T cells are required for protective immunity against a naturally occurring murine pathogen that infects the thymus and establish a novel infection model for MRV in B6 mice, providing the foundation for detailed future studies on MRV with the availability of innumerable mutant mice on the B6 background.

Combination Drug Products for HIV-A Word of Caution for the Transplant Clinician

Modern-day treatment regimens for human immunodeficiency virus (HIV) are not only highly effective, but are now more often available as convenient fixed-dose combination products. Furthermore, as medication adherence is of utmost importance in this setting, national guidelines endorse the use of such products. Transplant providers of HIV-infected patients will undoubtedly encounter these products, some of which contain medications known to drastically alter the metabolism of certain immunosuppressants. Herein, we describe an instance of drug interaction-induced calcineurin inhibitor (CNI) nephrotoxicity in a renal transplant recipient being started on a cobicistat-containing combination product for HIV. CNI toxicity, in turn, was resolved with the aid of phenytoin as an inducer of drug metabolism. This case underscores the importance of familiarity with newer combination products on the market and constant communication with HIV-positive transplant recipients and their providers.

Efficacy of spinal additives neostigmine and magnesium sulfate on characteristics of subarachnoid block, hemodynamic stability and postoperative pain relief: A randomized clinical trial

Background:

Intrathecal neostigmine and magnesium sulfate (MgSO₄) produce substantial antinociception, potentiate analgesia of bupivacaine without neurotoxicity.

Aims:

The aim was to investigate the effect of neostigmine and MgSO₄ on characteristics of spinal anesthesia (SA), hemodynamic stability and postoperative analgesia when added to 0.5% hyperbaric bupivacaine for SA.

Subjects and Methods:

In this prospective, randomized, double-blind study 75 American Society of Anesthesiologist status I and II adult females posted for major gynecological surgery were assigned to one of the three groups (n = 25). Group N received Neostigmine 25 μg, Group M received MgSO₄ 50 mg, Group C received 0.5 ml saline as an adjuvant to 17.5 mg hyperbaric bupivacaine. Onset, duration of block, heart rate, mean arterial pressure, postoperative analgesia, analgesic requirement, and adverse effects were recorded. Data expressed as mean (standard deviation) or number (%). P <0.05 were statistically significant.

Results:

The three groups were comparable in characteristics of SA. The mean duration of analgesia was significantly longer in Group N (5.1 h) followed by Group M (4.2 h) and Group C (3.8 h) (P = 0.0134). Analgesic requirement was significantly less in Group N followed by Group M and Group C (P = 0.00232). The pain score was significantly less in Group M (P < 0.05). The incidence of hypotension and vasopressor requirement was lowest (48%) in Group N than in Group M (64%) and Group C 84% (P = 0.0276). The incidence of bradycardia and atropine requirement was the lowest in Group M (P = 0.0354). Sedation was observed in 56% patients in Group M compared to 20% in Group N and 8% in Group C (P = 0.0004).

Conclusion:

Intrathecal Neostigmine and MgSo₄ does not affect characteristics of SA. Postoperative analgesia of neostigmine was better than MgSO₄. Neostigmine provides some protection against hypotension of SA whereas MgSO₄ protects against bradycardia.

Detailed phenotypic and molecular analyses of genetically modified mice generated by CRISPR-Cas9-mediated editing

The bacterial CRISPR-Cas9 system has been adapted for use as a genome editing tool. While several recent reports have indicated that successful genome editing of mice can be achieved, detailed phenotypic and molecular analyses of the mutant animals are limited. Following pronuclear micro-injection of fertilized eggs with either wild-type Cas9 or the nickase mutant (D10A) and single or paired guide RNA (sgRNA) for targeting of the tyrosinase (Tyr) gene, we assessed genome editing in mice using rapid phenotypic readouts (eye and coat color). Mutant mice with insertions or deletions (indels) in Tyr were efficiently generated without detectable off-target cleavage events. Gene correction of a single nucleotide by homologous recombination (HR) could only occur when the sgRNA recognition sites in the donor DNA were modified. Gene repair did not occur if the donor DNA was not modified because Cas9 catalytic activity was completely inhibited. Our results indicate that allelic mosaicism can occur following -Cas9-mediated editing in mice and appears to correlate with sgRNA cleavage efficiency at the single-cell stage. We also show that larger than expected deletions may be overlooked based on the screening strategy employed. An unbiased analysis of all the deleted nucleotides in our experiments revealed that the highest frequencies of nucleotide deletions were clustered around the predicted Cas9 cleavage sites, with slightly broader distributions than expected. Finally, additional analysis of founder mice and their offspring indicate that their general health, fertility, and the transmission of genetic changes were not compromised. These results provide the foundation to interpret and predict the diverse outcomes following CRISPR-Cas9-mediated genome editing experiments in mice.

Observations on the use of cidofovir for BK virus infection in renal transplantation

BACKGROUND

In renal transplantation, BK virus infection can result in significant graft nephropathy and loss. While reduction in immunosuppression (IS) is considered standard therapy, adjunct agents may be warranted. Data are suggestive of a possible role of cidofovir for the management of BK. This study aims to describe the course of BK viremia (BKV) in a large cohort of renal transplant patients receiving adjunct cidofovir.

METHODS

We evaluated kidney and kidney-pancreas recipients who received cidofovir combined with reduced IS for management of high-level BKV or BK virus nephropathy (BKVN). We examined the rate and timing of BKV clearance, and performed a multivariate analysis to identify risk factors associated with long-term (>6 months) viremia.

RESULTS

In total, 75 patients received a median of 13 doses of cidofovir in conjunction with reduced IS; 32 patients (43%) had short-term BKV (≤6 months), and 43 (57%) had long-term BKV. Overall, 53 of 75 patients (71%) eventually cleared BKV at a median of 4.2 months (interquartile range 2.1-9.3 months). Independent factors associated with long-term BKV included older age (odds ratio [OR] 1.1, P = 0.02), delayed graft function (OR 31.4, P = 0.01), and higher peak BKV (OR 12.8, P = 0.02), while BKV reduction by at least 1 log(10) copies/mL at 1 month of treatment was associated with clearance within 6 months (OR 49.3, P < 0.01). Patients with earlier clearance maintained stable graft function and no graft losses, while long-term BKV was associated with a 15% decline in estimated glomerular filtration rate.

CONCLUSIONS

Adjunct cidofovir resulted in preservation of renal function when viral clearance occurred within 6 months of initiation. This retrospective review defines factors predicting response to cidofovir in conjunction with reduced IS for BKVN or high-level BKV. Still, considering cost, frequency of administration, and treatment duration, a randomized trial is necessary to define the exact utility of cidofovir in the setting of BK virus infection.

Multiple human papillomavirus infections and HIV seropositivity as risk factors for abnormal cervical cytology among female sex workers in Nairobi

We estimated type-specific prevalence of human papillomavirus (HPV) and examined risk factors for abnormal cervical cytology among 296 female sex workers from Nairobi, Kenya. Over half (54%) were infected with a high-risk (HR) HPV type, of which HPV16 and 52 were the most common types. HIV-1 prevalence was 23% and HIV-1 sero-positivity was associated with high-grade cervical lesions, particularly among women with CD4 count less than 500 cells/mm(3) (odds ratio [OR] = 6.9; 95% confidence interval [CI]: 1.7-24.9). Among women who had normal cytology at the time of entry into the study, the risk of having an abnormal Pap smear within one year was significantly elevated for women with multiple HPV types at study entry (adjusted odds ratio [aOR] = 6.0; 95% CI: 2.3-15.7) and with a subset of HR HPV types (aOR = 4.2; 95% CI: 1.6-11.2). Detection of multiple concurrent HPV infections may be a useful marker to identify women at risk of developing precancerous lesions in populations of high HPV prevalence.

De novo donor specific antibodies and patient outcomes in renal transplantation

Single antigen identification of HLA antibodies is used to detect donor specific antibodies (DSAs). However, the impact of DSA elements such as class, relative strength, duration, and longitudinal effect on graft function and survival, remains unclear. Routine DSAs (LabScreen, One Lambda, Inc., Canoga Park, CA) and metabolic studies were performed at 1, 3, 6, 9, and 12 months post-transplant, and every 6 months for renal transplant recipients from 7/2007-7/2010 (n = 389). Biopsies were evaluated by updated Banff 2005 guidelines after two consecutive positive DSAs. Based on these tests, 25% of recipients developed de novo DSA. Those with DSA had increased acute rejection episodes (AR), higher creatinine (Scr), and worse graft survival. Three subgroups of these patients were identified based on duration: persistent DSA (> 1), isolated DSA, or no DSA. Persistent DSA patients were more likely to be African American, and have higher mean fluorescence intensity (MFI) and AR rates. Persistent DSA patients, with or without AR, had elevated Scr. Recipients with DQ-only DSA had higher rates of antibody mediated rejection (AMR). From this, we conclude that routine posttransplant DSA monitoring identifies recipients at risk for graft damage or loss. Persistent de novo DSAs correlated with inferior graft outcomes and AMR. With or without AR, DSA persistence was associated with worse outcomes, possibly warranting intervention. De novo DQ-DSA may be a biomarker for chronic damage and/or AMR, while an isolated DSA determination appears clinically insignificant.

Characterization of a familial small supernumerary marker chromosome in a patient with adult-onset tongue cancer

Cytogenetic analysis in peripheral blood lymphocytes of a 50-year-old female with tongue cancer showed the presence of one to three copies of a small supernumerary marker chromosome (sSMC) in a mosaic state. Family studies also revealed the marker in mosaic form in four (age <29 years) of eleven clinically normal individuals studied from her family of 16 individuals spanning three generations. Due to the extremely small size of the marker chromosome, identification by classical cytogenetics was not informative. Multicolor FISH followed by whole chromosome painting identified the marker as a derivative of chromosome 21. This is the first report of sSMC21 in an adult-onset tongue cancer patient and some of her family members with no clinical symptoms.

Activation of multiple molecular mechanisms for apoptosis in human malignant glioblastoma T98G and U87MG cells treated with sulforaphane

Glioblastoma is the most malignant and prevalent brain tumor that still remains incurable. Recent studies reported anti-cancer effect of the broccoli-derived compound sulforaphane. We explored the mechanisms of sulforaphane-mediated apoptosis in human glioblastoma T98G and U87MG cells. Wright staining and ApopTag assay confirmed apoptosis in glioblastoma cells treated with sulforaphane. Increase in intracellular free Ca2+ was detected by fura-2 assay, suggesting activation of Ca2+-dependent pathways for apoptosis. Western blotting was used to detect changes in expression of Bax and Bcl-2 proteins resulting in increased Bax:Bcl-2 ratio that indicated a commitment of glioblastoma cells to apoptosis. Upregulation of calpain, a Ca2+-dependent cysteine protease, activated caspase-12 that in turn caused activation of caspase-9. With the increased Bax:Bcl-2 ratio, cytochrome c was released from mitochondria to cytosol for sequential activation of caspase-9 and caspase-3. Increased calpain and caspase-3 activities generated 145 kD spectrin breakdown product and 120 kD spectrin breakdown product, respectively. Activation of caspase-3 also cleaved the inhibitor-of-caspase-activated-DNase. Accumulation of apoptosis-inducing-factor in cytosol suggested caspase-independent pathway of apoptosis as well. Two of the inhibitor-of-apoptosis proteins were downregulated because of an increase in 'second mitochondrial activator of caspases/Direct inhibitor-of-apoptosis protein binding protein with low pI.' Decrease in nuclear factor kappa B and increase in inhibitor of nuclear factor kappa B alpha expression favored the process of apoptosis. Collectively, our results indicated activation of multiple molecular mechanisms for apoptosis in glioblastoma cells following treatment with sulforaphane.

Percutaneous Closure of an Iatrogenic Puncture of the Aortic Arch

We report on the management of a rare complication of a vascular sheath being placed inadvertently in the aorta rather than in the venous system following thrombolytic therapy administration in a patient presenting with an acute myocardial infarction and complete heart block.

Convulsive syncope in young adults: think of a cardiac cause

Convulsive syncope is often misdiagnosed as epilepsy because of its similarity in clinical presentation. We present the case of a patient who had several such episodes before a definitive diagnosis was made. The diagnosis of prolonged sinus arrest was finally made with the valuable assistance of cardiac monitoring during a witnessed episode of convulsive syncope. Appropriate therapy was promptly introduced, i.e. temporary then permanent cardiac pacing. It is possible that any further delay in reaching the correct diagnosis and delivering appropriate treatment might have carried a significant risk of morbidity and mortality. Continuous electrocardiographic monitoring performed at an early stage is therefore crucial in the initial assessment of a young adult presenting with convulsive syncope, as a significant proportion may have a cardiovascular aetiology, particularly arrhythmias, for their syncopal episodes.

A study of chromosome aneuploidy in hereditary breast cancer patients and their healthy blood relatives

Chromosomal abnormalities that may predispose a group of individuals to develop certain neoplasms have been reported in lymphocytes. We evaluated cytogenetic abnormalities in 21 histopathologically confirmed primary breast cancer patients (BCPs), 52 healthy blood relatives (HBRs), belonging to 19 hereditary breast cancer families (HBFs) and 25 females as control. Phytohemagglutinin stimulated peripheral blood lymphocyte (PBL) cultures were used to study the chromosomal abnormalities in BCPs and their HBRs. Short term culture of the tumor tissue was also carried out in defined growth medium. Suitable metaphases (11 to 55) from tumors and a minimum of 100 metaphases from PBL were karyotyped for the cytogenetic analysis. Heterogeneous population of cells with random and nonrandom chromosomal abnormalities was noticed in tumors. In control groups 2-5% of metaphases showed numerical abnormalities, whereas this phenomenon was observed in 3-18% of metaphases in HBRs and 3-23% of metaphases in BCPs. In tumor tissue, 47.05% of BCPs showed numerical abnormalities in more than 16 metaphases. In lymphocytes, this event was observed in 33.33% of BCPs and 13.14% of HBRs. In controls 1.28%, in BCPs 52.04% (tumor) and 13.42% (lymphocytes), and in HBRs 9.03% of metaphases were found aneuploid. Statistically it was highly significant (Fisher's exact test, P<0.00001). In lymphocytes of BCPs, chromosomes 1, 6, 8, 9, 15, 17, 18, 20, and X and in HBRs, chromosomes 8, 15, 17, 18, and X were frequently involved. It can be inferred from the findings that the above mentioned chromosomes may have an important role in early stage of breast carcinogenesis in BCFs. Moreover, presence of similar abnormalities in HBR indicates inherited pattern of this genetic error among them.

Importance of dose intensity in neuro-oncology clinical trials: summary report of the Sixth Annual Meeting of the Blood-Brain Barrier Disruption Consortium

Therapeutic options for the treatment of malignant brain tumors have been limited, in part, because of the presence of the blood-brain barrier. For this reason, the Sixth Annual Meeting of the Blood-Brain Barrier Disruption Consortium, the focus of which was the "Importance of Dose Intensity in Neuro-Oncology Clinical Trials," was convened in April 2000, at Government Camp, Mount Hood, Oregon. This meeting, which was supported by the National Cancer Institute, the National Institute of Neurological Disorders and Stroke, and the National Institute of Deafness and Other Communication Disorders, brought together clinicians and basic scientists from across the U.S. to discuss the role of dose intensity and enhanced chemotherapy delivery in the treatment of malignant brain tumors and to design multicenter clinical trials. Optimizing chemotherapy delivery to the CNS is crucial, particularly in view of recent progress identifying certain brain tumors as chemosensitive. The discovery that specific constellations of genetic alterations can predict which tumors are chemoresponsive, and can therefore more accurately predict prognosis, has important implications for delivery of intensive, effective chemotherapy regimens with acceptable toxicities. This report summarizes the discussions, future directions, and key questions regarding dose-intensive treatment of primary CNS lymphoma, CNS relapse of systemic non-Hodgkin's lymphoma, anaplastic oligodendroglioma, high-grade glioma, and metastatic cancer of the brain. The promising role of cytoenhancers and chemoprotectants as part of dose-intensive regimens for chemosensitive brain tumors and development of improved gene therapies for malignant gliomas are discussed.

HER-2/neu gene amplification in breast imprint cytology analyzed by fluorescence in situ hybridization: direct comparison with companion tissue sections

Fluorescence in situ hybridization (FISH) is a validated method for detection of HER-2/neu gene amplification and was recently approved by the FDA for diagnostic use in paraffin-embedded tissue. Its use in cytologic specimens, however, has not been investigated. To see whether HER-2/neu gene amplification is detectable in cytologic specimens, we examined touch imprints and corresponding tissue sections of 27 breast carcinomas (20 invasive and 7 in situ) and 3 atypical epithelial hyperplastic lesions, using the FISH technique with the HER-2/neu DNA probe kit (Vysis, Inc., Downers Grove, IL). HER-2/neu gene amplification was determined, using the ratio of HER-2/neu:CEP 17 signal counts; a ratio of 2.0 or greater was considered amplified. Successful hybridization occurred in 55/60 (92%) slides. In all cases, at least one of the paired slides was adequate for evaluation. Whole-cell imprint and tissue section slides yielded comparable HER-2/neu:CEP 17 signal counts and ratios, including one case of low-level HER-2/neu gene copy numbers where the ratio was 2.0. Our findings indicate that whole-cell imprint cytology preparations are a reliable medium for HER-2/neu gene quantification by FISH, and may substitute for or complement tissue section analysis.

Vascular compression of the rostral ventrolateral medulla in sympathetic mediated essential hypertension

The pathophysiological factors of neurogenic or sympathetically mediated essential hypertension are unknown. Neurons close to the surface of the ventrolateral medulla (specifically, in the retro-olivary sulcus [ROS]) are integrally involved in the control of blood pressure by means of efferent connections to presympathetic neurons in the spinal cord. It is hypothesized that vascular contact with the ROS is pathogenically involved in neurogenically mediated hypertension. We evaluated that theory in 20 subjects with uncomplicated stage 1 to stage 2 essential hypertension (EHTN) (18 of whom completed the study). The baseline supine plasma norepinephrine level served as an index of central sympathetic outflow. The response of blood pressure to clonidine was used as a surrogate marker for neurogenically mediated hypertension. We also examined the relationship between those markers and evidence of anatomic abnormalities in the area of the ROS that was provided by magnetic resonance imaging. A vessel contacted the left ROS in 5 of the 18 subjects. Those 5 subjects had higher plasma norepinephrine concentrations than did the 13 subjects without this vascular contact (358+/-46 versus 76+/-43 pg/mL, P<0.001). These 5 subjects also exhibited a significant depressor response to clonidine that tended to be greater than that seen in the 13 subjects without vascular contact (-20.6+/-3.2 versus -13.6+/-9 mm Hg). Both race and baseline mean blood pressure had only an independent effect on the depressor response to clonidine. The findings are consistent with the theory that vascular contact with the left ROS may contribute to neurogenically mediated "essential" hypertension in some patients.

Bleomycin-induced chromosome damage in lymphocytes indicates inefficient DNA repair capacity in breast cancer families

In vitro mutagen susceptibility has been observed as a predictor of cancer risk. To evaluate susceptibility to mutagen, we have studied the response to in vitro bleomycin (BLM) treatment in cultured peripheral blood lymphocytes (PBL) of 9 breast cancer families (BCFs). Eleven breast cancer patients (BCPs) and 36 healthy blood relatives (HBRs) from BCFs were included in the study. Data were compared with 22 healthy control women. The frequencies of chromosomal aberrations were evaluated after exposure to BLM in the last five hours. Mean frequency of BLM-induced chromosomal aberrations per cell (CA) observed among BCPs was significantly higher as compared to their HBRs as well as control subjects. Moreover, mean BLM-induced CA/cell value observed for HBRs was also significantly higher than that of control subjects. In comparison to controls, it was observed that there was four times more cancer risk in BCPs (OR=4.148, 95% CI=5.83-687.46) and 2.5 times more cancer risk in HBRs (OR=2.67, 95% CI=5.31-39.25). Lymphocytes from 90% of BCPs and 69% of HBRs were found to be sensitive to BLM (using a cutoff value = controls group mean + 1 SD). Thus, lymphocytes of BCPs and their HBRs were more sensitive to BLM exposure as compared to controls. Our finding indicated inefficient DNA repair capacity in BCFs. The HBRs in BCFs, having increased BLM-sensitivity, may be at higher risk to develop a similar cancer.

Spontaneous chromosomal instability in breast cancer families

Spontaneous chromosomal instability has been correlated with cancer predisposition. In the present study, the phenomenon has been evaluated using two cytogenetic markers, namely, frequency of spontaneous sister chromatid exchanges (SCE) and spontaneous chromosomal aberrations (CA) in peripheral blood lymphocytes of hereditary breast cancer (HBC) patients (n = 11) and healthy blood relatives (HBR, n = 36). A statistically significant difference was observed for both the endpoints between HBC patients and controls (P < 0.001), HBC patients and HBR (P < 0.001), as well as HBR and controls (P < 0.001). Thus, 63.64% of the HBC patients and 25% of HBR showed a mean CA/cell value higher than the highest mean CA/cell value of the controls (0.11 CA/cell). Similarly, 81.81% of the HBC patients and 61.11% of HBR showed a mean SCE/cell value higher than the highest mean SCE/cell value of the controls (9.60 SCE/cell). Chromosomal aberrations were more frequently observed in the B and E group of chromosomes in HBC patients and HBR. These findings primarily indicate the high level of chromosomal instability in breast cancer families, and might be one of the predisposing factors for high risk of cancer in HBR.

"Dual pathology" and the significance of surgical outcome in "Dostoewsky's epilepsy"

A patient with a right occipital arterio-venous malformation (AVM) and seizures heralded by "lights", and experiencing "ecstasy" underwent a right occipital lobectomy after the AVM was embolized. Thereafter, seizures began with motor arrest and lip smacking, but never again with "light and ecstasy". A right temporal lobectomy and electrocorticogram (E.Co.G) were performed under local anesthesia four years after occipital lobectomy. Abundant spiking activity was recorded from the right hippocampus which showed gliosis and neuronal loss in the pathology studies. Electrical stimulation of the lateral and basal temporal cortices failed to elicit the vision of "lights" or the experience of "ecstasy". The patient has had two seizures in the last two years as a result of a lapse in taking his anti-convulsant medication. He now lives alone, seizure-free. The possible abnormally induced functional network organization and structures involved in the production of the "ecstasy" phenomenon are discussed.

Anatomy and clinical significance of the horizontal cleft in the infrapatellar fat pad of the knee: MR imaging

OBJECTIVE

The purpose of this study was to determine the prevalence and nature of a horizontal cleft in the posterior aspect of Hoffa's infrapatellar fat pad and to show pathologic processes involving this cleft.

MATERIALS AND METHODS

Fifty consecutive MR imaging examinations of the knee were evaluated for the presence and appearance of a cleft in the infrapatellar fat pad. Examples of abnormalities involving the cleft were collected from additional MR studies. MR imaging, gross dissection, and histologic examination of a cadaveric knee were also performed to evaluate the anatomy and histology of the cleft.

RESULTS

The cleft in the infrapatellar fat pad was revealed on MR imaging in 45 of 50 knees and had a variable shape, either linear (82%), pipe-shaped (7%), or globular-shaped (11%). Joint effusion or anterior cruciate ligament tear did not affect the appearance of the cleft. The cleft was located anterior to the distal insertion of the anterior cruciate ligament on the tibia. At gross dissection of the cadaveric knee, the roof of the cleft was formed by the ligamentum mucosum (infrapatellar plica), and the cleft was lined with synovium. The prospective evaluation of additional MR imaging examinations of the knee revealed pathologic entities of the cleft such as ganglion cysts, loose bodies, nodular synovitis, and amyloid.

CONCLUSION

A horizontal cleft located in the posterior aspect of the infrapatellar fat pad is a common and normal MR imaging finding with a prevalence of 90%. The horizontal cleft is lined with synovium and its roof is formed by the ligamentum mucosum (infrapatellar plica). This cleft communicates with the knee joint. A distended cleft can form a prominent recess mimicking pathologic processes; conversely, disorders can arise in the cleft.

Combined approaches for resection of extensive glomus jugulare tumors. A review of 12 cases

Complete resection with conservation of cranial nerves is the primary goal of contemporary surgery for glomus jugulare tumors. This publication reports the value of combined surgical approaches in achieving this goal in 12 patients with extensive tumors. Eleven of these tumors were classified as Fisch Class C and/or D, while eight were categorized as Jackson-Glasscock Grade III or IV. Intracranial (intradural) extension was present in 10 patients; four patients had tumor extension into the clivus and two into the cavernous sinus. The petrous internal carotid artery (ICA) was involved in eight and the vertebral artery (VA) in one. Subtemporal-infratemporal, retrosigmoid, and/or extreme lateral transcondylar approaches were added to the usual transtemporal-infratemporal approach. This improved the exposure, provided early control of the petrous ICA, and facilitated tumor removal from the clivus, cavernous sinus, posterior fossa, and foramen magnum, allowing a single-stage resection in eight patients. Ten patients had a complete microscopic resection with no mortality. The facial nerve was preserved in nine cases, with tumor involvement requiring nerve resection followed by grafting in the remaining three. Mobilization of the facial nerve was avoided in five cases; of these, three had intact function and two had House-Brackmann Grade III function on follow-up review. Only one patient had a mild persistent swallowing difficulty. The ICA was preserved in 10 patients and resected in two, while the VA required reconstruction in one case. There were no instances of stroke, and blood transfusions were required in five patients who had tumors with nonembolizable ICA or VA feeders. While complete resection provides the best possibility for cure, the important role of adjuvant radiation therapy in cases with residual tumor is discussed. The importance of degrees of brain-stem compression and vascular encasement is emphasized in classifying the more extensive tumors.

Meningiomas: correlation between MRI characteristics and operative findings including consistency

The findings on magnetic resonance imaging (MRI) in 73 surgically verified intracranial meningiomas were correlated with their histology and consistency during resection. T 1-weighted imaging was least useful since most of the tumours were iso-intense, similar to cortical grey matter regardless of histology or tumour consistency. The signal intensity on T2-weighted images was found to best correlate with both the histology and consistency of the meningioma. Generally, the low intensity portion of the tumour on T2-weighted images indicated a more fibrous and harder character, while the higher intensity portions indicated a more soft character. Most of the fibroblastic meningiomas showed the features of a hard tumour while angioblastic tumours showed the features of soft tumours. Tumours predicted to be harder on MR imaging generally took longer to resect than softer ones, and this relationship was shown best for the larger tumours. Using linear regression analysis, it appears that operative time for soft tumours is more affected by factors other than tumour consistency. Blood loss during surgery was also unrelated to the consistency of the tumour. These results suggest that the histology and consistency of meningiomas may be predictable from findings on T2-weighted imaging, and this may also predict the difficulty and time required for resection.

Isolated intramedullary spinal artery aneurysm presenting with quadriplegia. Case report

The case is presented of an isolated intramedullary posterior spinal artery aneurysm at the C-2 level in a 3-year-old girl. Quadriplegia related to probable intramedullary hemorrhage was the presenting symptom. Magnetic resonance imaging revealed findings consistent with an intramedullary vascular lesion, and vertebral angiography confirmed this to be an aneurysm of the posterior spinal artery. No associated vascular abnormalities were noted, and the aneurysm was successfully resected. Previous reports of isolated spinal aneurysms are reviewed.