Bronchoscopic lung volume reduction by instillation of fibrinogen and thrombin in COPD patients with homogenous emphysema

BACKGROUND

The new endobronchial therapy called biological lung volume reduction (BioLVR) involves using a rapid polymerizing sealant to block off the most emphysematous portions of the lungs. The primary mechanism of action is resorption atelectasis, which is then followed by inflammation and remodeling of the airspace. The remodeling process will result in the formation of scars, leading to the contraction of the lung tissue. As a result, a decrease in functional lung volume is anticipated for a period of 6-8 weeks.

OBJECTIVE

Assessing the safety and effectiveness of bronchoscopic installation of (fibrinogen and thrombin) in COPD patients with homogeneous emphysema in terms of radiological, physiological, and quality of life outcomes.

METHODS

Between December 2017 and December 2019, 40 COPD patients with homogeneous emphysema were studied using a fiber optic bronchoscope while they were awake but sedated. Tanta University Hospitals' chest medicine department collaborated with the diagnostic radiology department of the Faculty of Medicine.

RESULTS

All the following parameters were reduced from their initial values: HRCT volumetry, RV/TLC, mMRC dyspnea scale, CAT score, 6MWT, FEV1, and the FEV1/FVC ratio at the first, third, and sixth months from the beginning (p = 0.001). One individual (0.025%) had pneumonia, whereas three individuals had COPD (0.075%). Using fibrin glue produced locally, biological lung volume reduction (Bio LVR) may be an effective treatment for advanced homogenous emphysema.

CONCLUSION

By using locally prepared fibrin glue the biologic lung volume reduction (Bio LVR) may be a convenient method to treat advanced homogenous emphysema.

Dynamic Contrast Enhanced MRI as a Biomarker of Tumor Response and Oncologic Outcomes in Head and Neck Cancer: Results of a Single Institution Prospective Imaging Study

PURPOSE/OBJECTIVE(S)

We aim to determine the correlation between vascular parameters of Dynamic contrast enhanced (DCE) MRIs and tumor response and outcomes in head and neck (HNC) patients treated with definitive radiation therapy (RT).

MATERIALS/METHODS

Eighty-two HNC patients are included in this prospective study in one institute. All patients had malignant head and neck neoplasm indicative of curative- intent treatment. Patients were imaged using MRIs pre-, mid-, and post-RT completion at 8-12 weeks. T2-weighted sequences were used for tumor contouring then it was co-registered to respective DCE images. The response to treatment was checked at mid-radiotherapy (mid-RT) and at the end of RT. Mid-RT MRI was co-registered to baseline images and the manually segmented baseline primary tumor regions of interest were propagated to mid-RT images. Quantitative maps (Ktrans, Kep, Ve and Vp) were generated with the extended Tofts pharmacokinetic models and were used for analysis. These vascular parameters were presented as a mean value and percentile using histogram analysis and the following parameters were extracted using an in-house programming environment script: mean, 5th, 10th, 20th, 30th, 40th, 50th (i.e., median), 60th, 70th, 80th, 90th, 95th percentile. The non-parametric Wilcoxon signed-rank test was used to assess the changes of mid-RT DCE parameters compared to baseline. Recursive partitioning analysis (RPA) was used to identify the delta DCE threshold associated with relapse. We assessed the identified thresholds' correlation with oncological and survival endpoints using Cox regression with and without standard clinical variables.

RESULTS

The median age for patients is 61 years old (33-78 range). Never smokers are 39 (47%), 35 (43%) are former smoker and 8 (10%) are current smoker with a mean value of 14 pack per year and 26 standard deviations. Using AJCC 8th edition, 39 (47%) are stage I and 19 (23%) are stage II and stage III and IV are 15 (18%) and 9 (10%) respectively. HPV positive are 72 (88%). For patients with GTV-P at baseline (n = 60), 11 (18%) had mid-RT CR at the primary site which increased to 50 (83%) post-RT. The LC and RFS for the entire cohort were 91.4%, and 79.2% respectively. In GTV-P, none of the pre-radiotherapy DCE parameters were correlated with LC or RFS. Wilcoxon signed rank test was statistically significant in 80, 90 and 95 percentiles with (p<0.05). RPA analysis identified different thresholds for each DCE parameter, and its inclusions to the multivariate model improved its performance. In GTV-P, RPA analysis identified ΔKtrans 40 percentiles >15.6% at mid-RT as the most significant point. When this value of ΔKtrans added to the multivariate analysis it was associated with a significantly better model performance in RFS (p = 0.00001).

CONCLUSION

DCE parameters are a very promising tool to correlate with response and outcomes in H&N cancer patients. Future work is warranted for external validation of our findings.

Natural History and Clinical/Dosimetric Determinants of Osteoradionecrosis in a Large Cohort of Head and Neck Cancer Following Curative Radiotherapy: Debunking the Myth of Decreased Rates of Osteoradionecrosis in the Modern Radiotherapy Era

PURPOSE/OBJECTIVE(S)

Osteoradionecrosis (ORN) of the mandible is the most devastating toxicity following head and neck cancer (HNC) radiotherapy (RT). The rate of ORN occurrence has been debatable in the modern era of advanced RT. We aim to determine the natural history and time to ORN development in a large cohort of HNC.

MATERIALS/METHODS

After IRB approval, we identified HNC patients treated with curative-intent RT between 2005 and 2020 at MD Anderson Cancer Center. Dental oncology notes were reviewed and all dental procedures were recorded. Available dose volume histograms (DVHs) for the segmented mandibular volumes were extracted. Based on our previously published ORN normal tissue complication probability (NTCP) model, any dental procedure pre-RT is a clinical high-risk factor and, therefore, data were coded as (high vs. low clinical risk) accordingly. We also coded the dosimetric risk factors to (high vs. low dosimetric risk) according to our published DVH thresholds (high dosimetric risk if any applies: V45≥40%, V55≥25%, and/or D30 ≥40 Gy). Finally, patients were classified to four groups according to combined clinical and dosimetric risk factors (No, clinical, dosimetric, and both). We used the Kaplan-Meier method to calculate time to ORN development and ORN-free survival. For time to ORN development, any grade ORN occurrence was coded as event and all others were censored. For ORN-free survival, death and ORN were coded as events and all others were censored. Log-rank test was used to compared curves of different risk groups.

RESULTS

One thousand eight hundred sixty-six patients were included. Median follow-up was 38 months (range 4-162). ORN was reported in 252 patients (13.5%). The median time to ORN development was 18.5 months (range 4-145). 95 patients (37.7%) developed ORN after 2-years post-RT. The 1-, 3-, and 5-year ORN rates were 4.7%, 12.7%, and 17.8%, respectively. The 1-, 3-, and 5-year ORN-free survival were 94.3%, 85.5%, and 80.3%, respectively. There were statistically significant differences (P < 0.0001) between ORN-free survival in different clinical/dosimetric risk factors. The patients with no, clinical-only, dosimetric-only, and both clinical and dosimetric risk factors were 35%, 19%, 22%, and 24%, respectively. The 5-year ORN-free survival was 94.3%, 89.8%, 76.3%, and 69.6% for patients with no, clinical-only, dosimetric-only, and both clinical and dosimetric risk factors, respectively. The hazard-ratio (HR) of ORN development in clinical-only, dosimetric-only, and both clinical and dosimetric risk groups was 2.1, 5.4, and 7.5 compared to the no risk group (P<0.05 for all).

CONCLUSION

Our findings indicate that ORN remains a remarkable toxicity hazard for HNC survivors. A prolonged surveillance time is required for the majority of HNC survivor since more than one-third of the ORN events occurred after 2-year follow-up. Patients with combined clinical and dosimetric risk factors have a staggering ORN risk profile and are proper candidates for future prophylactic pharmacotherapy clinical studies.

Longitudinal Monitoring of Quantitative Imaging Kinetics of Primary Tumor and Nodal Volumes Using the MR-Linac Device in Head and Neck Cancer Patients

PURPOSE/OBJECTIVE(S)

We aim to characterize the serial quantitative apparent diffusion coefficient (ADC) changes of the target disease volume using diffusion-weighted imaging (DWI) acquired weekly during radiation therapy (RT) on a 1.5T MR-Linac and correlate these changes with tumor response and oncologic outcomes for head and neck squamous cell carcinoma (HNSCC) patients.

MATERIALS/METHODS

Thirty patients with pathologically confirmed HNSCC and received curative-intent RT at the University of Texas MD Anderson Cancer Center, were included in this prospective study. Baseline and weekly MRIs (weeks 1-6) were obtained, and various ADC parameters (mean, 5th, 10th, 20th, 30th, 40th, 50th, 60th, 70th, 80th, 90th and 95th percentile) were extracted from the target regions of interest (ROIs). Pre-RT and weekly ADC parameters were correlated with response during RT, loco-regional control, and the development of relapse using the Mann-Whitney U test. The Wilcoxon signed-rank test was used to compare the weekly ADC versus baseline values. Weekly volumetric changes (Δvolume) for each ROI were correlated with ΔADC using Spearman's Rho test. Recursive partitioning analysis (RPA) was performed to identify the optimal ΔADC threshold associated with different oncologic outcomes.

RESULTS

There was an overall significant rise in all ADC parameters during different time points of RT compared to baseline values for both GTV-P & GTV-N. The increased ADC values for GTV-P were statistically significant only for primary tumors achieving CR during RT. RPA identified GTV-P ΔADC 5th percentile >13% at the 3rd week of RT as the most significant parameter associated with CR for GTV-P during RT (p <0.001). Baseline ADC parameters didn't significantly correlate with response to RT or other oncologic outcomes. There was a significant decrease in residual volume of both GTV-P & GTV-N throughout the course of RT. Additionally, a significant negative correlation between mean ΔADC and Δvolume for GTV-P at the 3rd and 4th week of RT was detected (r = -0.39, p = 0.044 & r = -0.45, p = 0.019, respectively).

CONCLUSION

Assessment of ADC kinetics at regular intervals throughout RT is potentially able to predict the response to RT and oncologic outcome. Further studies with larger cohorts and multi-institutional data are needed for validation of our results.

Deep Learning Based Prognostic Prediction in Oropharyngeal Cancer Patients Using Multiparametric MRI Inputs

PURPOSE/OBJECTIVE(S)

While prognostic outcomes for oropharyngeal cancer (OPC) patients have improved in recent years, patients still face a non-negligible risk of disease recurrence or death. Accurately predicting post-therapy prognosis would be highly valuable for risk stratification and treatment guidance for OPC patients. Recent studies using PET/CT data have demonstrated the effectiveness of large-scale, end-to-end image-based deep learning (DL) models for predicting progression-free survival (PFS) in OPC patients. Multiparametric MRI (mpMRI), which combines anatomical and functional MRI sequences, has the potential to offer similar results, and has the added advantage of high-frequency longitudinal imaging capabilities, such as through MR-Linac devices. Therefore, this study aimed to develop a DL model using mpMRI data to predict PFS, and to evaluate the impact of anatomical and functional input channels on model performance.

MATERIALS/METHODS

From a large-scale head and neck cancer database at MD Anderson Cancer Center, treatment-naïve OPC patients with available pre-radiotherapy mpMRI imaging were selected for this study. mpMRI images used for this study included T2-weighted images (T2) and apparent diffusion coefficient (ADC) maps. PFS event status was defined as having either a local, regional, or distant failure, and/or death; data were right censored if an event had not occurred. Images were resampled to the T2 resolution, normalized to a [-1,1] scale, and cropped to the field of view of the ADC image for use in DL models. A DL convolutional neural network model based on the DenseNet121 architecture from the Medical Open Network for AI (MONAI) Python package using a negative log-likelihood loss function was implemented. The model used mpMRI images as input channels and 20 output channels representing the different time intervals of the predicted PFS conditional probabilities of surviving that time interval; final PFS in days was obtained by summing the cumulative probability of surviving each interval times the interval duration. A 5-fold cross validation approach was used for model training and evaluation. Separate models using only T2, only ADC, and T2 + ADC channel inputs were compared. Model performance was measured using the C-index.

RESULTS

Out of 1154 patients, 404 met inclusion criteria. The overall PFS event rate was 16%. Median C-index values from the 5-fold cross validation were 0.62, 0.67, and 0.69 for the ADC, T2, and T2+ADC models, respectively.

CONCLUSION

Using large-scale datasets and open-source DL implementations, we find that OPC PFS prediction models using mpMRI data yield modest but comparable performance to existing models (i.e., state-of-the-art reference performance using PET/CT). Moreover, combining mpMRI channels may increase the performance of models for OPC prognostic prediction. Future work will involve integration of additional timepoints, additional mpMRI images, clinical variables, and saliency maps.

Assessment of Dynamic Contrast Enhanced (DCE) MRI for Detection of Radiotherapy Induced Alteration in Mandibular Vasculature

PURPOSE/OBJECTIVE(S)

We aim to determine the kinetics of DCE-MRI changes in various mandibular risk volumes based on radiation (RT) dose received.

MATERIALS/METHODS

Eighty-eight head and neck cancer (HNC) patients (Pts) who underwent definitive RT were enrolled in this prospective study after IRB approval and informed consent. Images were acquired at pre-RT (Baseline), 3 weeks after RT start date (Mid-RT), 3 mos post-RT (PostRT1), and 6 mos post-RT (PostRT2). Manually segmented mandibular volumes on T2-weighted images were propagated to co-registered DCE-MRIs. Planning CTs and dose grids were also co-registered to corresponding baseline T2 images to create 3-D dose subvolumes. These were used to create 3 risk subvolumes; <30 Gy, 30-50 Gy, and >50 Gy ROIs. DCE images of different timepoints (TPs) were deformably co-registered and the dose subvolumes were propagated to each TP. We used the extended-Tofts model to generate the vascular quantitative maps (Ktrans and Ve). Each subvolume histogram parameters were extracted at each TP. Wilcoxon Signed Rank test was used to compare the changes at different TPs compared to baseline. We classified Pts' delta parameters at different TPs -based on our prior extensive QA assessment- into Pts with stable vascular profile (±25% change), Pts with significant increase (>25% change) and Pts with significant decrease (<-25%). Chi-square test was used to assess the change at different TPs.

RESULTS

For <30 Gy subvolumes, there were no significant changes (p > 0.05) in the studied DCE parameters at all TPs except a significant decrease (p < 0.001) in median Ktrans at PostRT2. For 30-50 Gy subvolumes, there was a significant increase in median Ktrans that started at MidRT (p = 0.006) and continued at PostRT1 (p = 0.04) but recovered to baseline values at PostRT2. Median Ve on the other hand only showed significant increase at PostRT1 (p = 0.001), but other TPs were not significantly different compared to baseline. Similarly, subvolumes >50 Gy showed same kinetics as in 30-50 Gy with significant increase of Ktrans at MidRT and PostRT1 and significant increase in Ve in only PostRT1 (P <0.05). For <30 Gy, there was significant increase in the number of Pts with stable or decrease in Ktrans at PostRT2 compared to earlier TPs (70% vs. 60% at PostRT1 and 54% at MidRT p = 0.003). 30-50 Gy subvolumes showed similar profile like <30 Gy with significant increase in the percentage of Pts with recovery at PostRT2. However, for >50 Gy, there was no significant increase in the number of Pts who recovered at PostRT2 (p = 0.3). Ve showed no significant increase in the percentage of Pts with recovery at different TPs (p > 0.05).

CONCLUSION

Results showed that for all dose mandibular subvolumes, there is an acute vascular insult that tends to recover at +6 months post-RT except for a selective group of patients who continue to have persistence of the vascular insult at high dose subvolumes. These findings are of importance for future selection of high risk population for prophylactic intervention against osteoradionecrosis.

Disease Control and Toxicity Outcomes after Intraoperative HDR Brachytherapy for Neck Recurrences in Patients Previously Irradiated Head and Neck Cancer

PURPOSE/OBJECTIVE(S)

Despite recent advances in local and systemic therapies for head and neck squamous cell carcinomas (HNSCC), the most common types of treatment failure remain local and regional. Patients with HNSCC also have a higher risk of developing secondary head and neck tumors due to a field cancerization phenomenon. Treatment of these recurrences poses a challenge, particularly in patients having previously received full dose external beam radiotherapy (EBRT) to the head and neck region. This study evaluates the clinical outcomes of intraoperative Harrison-Anderson-Mick applicator (HAM) HDR brachytherapy (BT) after salvage neck dissection for neck recurrences in patients previously irradiated for HNSCC.

MATERIALS/METHODS

All patients having received HAM BT for HNSCC neck recurrences at a single institution were identified. Demographic, treatment, disease control and toxicity data were collected retrospectively. Toxicity was graded as per Common Terminology Criteria for Adverse events version 5. The Kaplan Meier method was used to assess overall survival (OS) and ipsilateral regional control (IRC) from the time of HAM BT.

RESULTS

Nineteen patients with regional recurrence of HNSCC were treated with HAM BT Ir-192 between July 2006 and June 2022, with a median follow-up for survival of 51.4 months (range: 2.5-186.7). The median BT dose was 12.5 Gy delivered intraoperatively at 5 mm tissue depth/1 cm from source. Fifteen patients (78.9%) also received postoperative EBRT to a median dose of 46 Gy in 23 fractions and 13 (68.4%) received systemic therapy. Six patients (31.6%) developed ipsilateral neck recurrences (4 who had adjuvant EBRT and 2 who did not), 2 patients had primary site recurrences and 5 patients developed distant metastases. In terms of acute toxicity, 4 patients had grade 3 dysphagia requiring feeding tube (FT) placement and one patient required surgical intervention for wound necrosis. In terms of late toxicity, 2 additional patients required FT placement and 1 was able to have it removed. No grade 4+ late toxicities were noted. The IRC at the site of HAM BT at 1 year was 71.5% and 63.6% at 5 years. The 1-year OS was 81.3% and 5-year OS was 40.9%.

CONCLUSION

Intraoperative HAM BT resulted in favorable rates of IRC with acceptable toxicity in the reirradiation setting for HNSCC.

Multi-Specialty Physician Performance in Predicting Radiographic Extranodal Extension in Nodal Metastases of Oropharyngeal Squamous Carcinoma

PURPOSE/OBJECTIVE(S)

The presence of extranodal extension (ENE) in oropharyngeal (OPC) cancer patients is an important prognostic factor and can be used to determine the optimal course of treatment; however, currently, the gold standard method for ENE assessment is performed pathologically, which can only be done in a post-hoc fashion after surgical treatment has already been performed. Anatomic imaging features are being explored as a possible method for the pre-therapeutic determination of ENE, but there is currently no objective standard for the assessment of ENE from radiographic images. In this study we recruited expert clinicians, including surgeons, radiation oncologists, and radiologists, across multiple institutions to individually evaluate the presence of ENE from CT scans in order to assess the performance of radiographic ENE evaluation in human experts across different specialties.

MATERIALS/METHODS

Pre-therapy contrast-enhanced CT scans were collected from 25 OPC patients with lymph node metastasis that were pathologically evaluated for ENE after surgical resection. 5 scans were randomly chosen to be duplicated and left/right inverted, resulting in a total of 30 scans of which 21 had pathologically-confirmed ENE. To hide the inversion, all images were cropped to only show the oropharynx region. 34 expert head and neck cancer physicians, comprised of 12 surgeons, 11 radiation oncologists, and 11 radiologists, then separately evaluated the 30 CT scans using 3D Slicer for ENE presence or absence with their prediction confidence. For each physician, discriminative performance metrics were measured by calculating the accuracy, sensitivity, specificity, area under the receiver-operating characteristic curve (AUC), and Brier score, a measure of the probabilistic prediction accuracy calculated from their confidence where a lower Brier score is better. Statistical tests were performed using the Mann Whitney U test.

RESULTS

The median (interquartile) study results are shown in Table 1. There was no statistically significant difference among groups for accuracy or AUC, but significant differences among groups for Brier score, sensitivity, and specificity.

CONCLUSION

In this study we provide evidence that expert physicians, regardless of specialty, show poor performance in assessing the presence of ENE from CT scans in OPC patients. These results agree with conclusions from previous literature, and suggest the need for further research in the automated analysis of radiographic ENE.

DASS Good: Explainable Data Mining of Spatial Cohort Data

Developing applicable clinical machine learning models is a difficult task when the data includes spatial information, for example, radiation dose distributions across adjacent organs at risk. We describe the co-design of a modeling system, DASS, to support the hybrid human-machine development and validation of predictive models for estimating long-term toxicities related to radiotherapy doses in head and neck cancer patients. Developed in collaboration with domain experts in oncology and data mining, DASS incorporates human-in-the-loop visual steering, spatial data, and explainable AI to augment domain knowledge with automatic data mining. We demonstrate DASS with the development of two practical clinical stratification models and report feedback from domain experts. Finally, we describe the design lessons learned from this collaborative experience.

58 EVALUATION OF DIABETES MELLITUS IN A COHORT OF FRAIL OLDER ADULTS

Background

The aim of this study was to identify the prevalence of diabetes in a cohort of frail older adults who attended a model 3 hospital and explore the relationship between frailty and diabetes in this cohort. Prognosis and treatment of diabetes can vary greatly in the presence of frailty.

Methods

A multidisciplinary team provide liaison geriatric input to frail older adults in this hospital. Comprehensive geriatric assessments (CGAs) are carried out on patients identified using a VIP tool or via inpatient consults. These CGAs were reviewed regarding frailty scores, social/falls history, medications and diabetes complications including hypoglycaemia.

Results

CGAs were reviewed for 213 patients from September to November 2019. Fifty eight patients had a diagnosis of diabetes (27.2%), and all were type 2. The median age was 84. The average Clinical Frailty Scale score was 5.4 indicating mild to moderate frailty. Over two thirds of patients (n = 137) were on more than 5 medications. Seventy-six patients had a history of falls, and 24 (31.5%) of those had diabetes. Twenty-one patients were prescribed either sulphonylureas and/or insulin, and 7 of these were living alone. One patient had a sulphonylurea stopped on admission following CGA. Five patients had a documented history of hypoglycaemia, 2 of these patients were on insulin and 1 was on a sulphonylurea. The median HbA1c was 49 mmol/mol. Fifteen patients had diabetes complications, including 3 with retinopathy and 6 with neuropathy. The median duration of diabetes was 9.5 years. The majority of patients were managed at primary care level (n = 48, 82.75%).

Conclusion

The management of frail older adults with diabetes is complicated by multimorbidity and increased risk of adverse effects of treatment such as hypoglycaemia. Frailty assessment should be a routine component of a diabetes review for all older adults, and then glycaemic targets and medication choices should be adjusted accordingly.

Female Genital Tuberculosis, a Rare Lesion Mimicking Ovarian Carcinoma, with Granulosa Cell Tumor: A Case Report

Introduction:

Tuberculosis (TB) of the upper genital tract is a rare disease worldwide. TB should be always considered in the differential diagnosis of a pelvic or adnexal mass as it may diagnosed as ovarian carcinoma but both have completely different treatment. Therefore, recognition of TB is important for surgeons and histopathologists, in order to set a proper plan for management and avoid unnecessary extensive therapy. Granulosa cell tumor of the ovary is a rare type of ovarian cancer that accounts for approximately 2% of all ovarian tumors. This type of tumor is known as a sex cord-stromal tumor and usually occurs in adults. Thorough search in English literature revealed only 2 case reports showed combination between genital TB and granulosa cell tumor.

Case summary:

A 68 years old female patient complained of vaginal bleeding for four months. She had no personal or family history of TB. An ultrasound study showed a 2x1.5 cm mixed echogenic mass in the right adnexa. Based on her clinical and imaging findings which suggestive of ovarian cancer, the patient underwent panhystrectomy and bilateral salpingoophrectomy. The gross examination of the specimen revealed distended and coiled tubes with right adnexal mass measured 2x1.5 cm and dissection of the uterus revealed erythematous endometrium with yellowish secretions. The histopathologic assessment of right adnexal mass revealed malignant neoplasm *Granulosa cell tumor* formed of short polygonal cells arranged in diffuse sheets with patternless pattern. The malignant cells showed nuclear grooving. There was no necrosis or other ovarian neoplastic element. The histopathologic assessment of both tubes and endometrium revealed infiltration by multiple nodular granulomas. Each granuloma was formed of multinucleated giant cells and epithelioid cells rimmed by lymphocytes with occasional central caseation *genital tuberculosis*.

Conclusion:

The conclusion of this case report is to stress upon keeping genital TB in mind as a potential differential diagnosis for ovarian carcinoma.

Objective Comparison Between Spreader Grafts and Flaps for Mid-Nasal Vault Reconstruction: A Randomized Controlled Trial

Objective

The goal of rhinoplasty is not exclusively aesthetic and the nasal function should always be considered. Several rhinoplasty techniques can participate in nasal valve dysfunction (eg, dorsal hump reductions). Therefore, mid-nasal vault reconstruction by spreader grafts or flaps is mandatory in these cases. To date, there is a literature gap in comparing both techniques objectively. This study shows an objective comparison between spreader grafts and flaps for mid-nasal vault reconstruction.

Material and Methods

This study was a double-blind randomized controlled trial including 40 patients who were randomly divided into 2 groups. Group 1 (20 patients) underwent spreader grafts insertion, whereas group 2 (20 patients) underwent spreader flap placement technique. Pre-operative active anterior rhinomanometry measurements were compared to 6-month post-operative measurements. Data were summarized as mean (standard deviation) for the quantitative variables. Comparisons between the 2 groups were done using unpaired t test.

Results

In both groups, a significant decrease in nasal resistance was noted in both the right and left sides 6 months post-operatively (P < .001). However, the comparison between the 2 both groups showed no statistical significance.

Conclusion

Both spreader grafts and flaps, which are used for the mid-nasal vault reconstruction, have comparable and effective results in reducing the nasal resistance as evidenced by active anterior rhinomanometry measurements.

Ursodeoxycholic acid upregulates ERK and Akt in the protection of cardiomyocytes against CoCl2

Ursodeoxycholic acid (UDCA) is used to treat liver diseases and demonstrates cardioprotective effects. Accumulation of the plasma membrane sphingolipid sphingomyelin in the heart can lead to atherosclerosis and coronary artery disease. Sphingomyelinases (SMases) break down sphingomyelin, producing ceramide, and inhibition of SMases activity can promote cell survival. We hypothesized that UDCA regulates activation of ERK and Akt survival signaling pathways and SMases in protecting cardiac cells against hypoxia. Neonatal cardiomyocytes were isolated from 0- to 2-day-old Sprague Dawley rats, and given 100 μM CoCl2, 150 μM H2O2, or placed in a hypoxia chamber for 24 h. The ameliorative effects of 100-μM UDCA treatment for 12 h were then assessed using MTS, QuantiGene Plex (for Smpd1 and Smpd2), and SMase assays, beating rate assessment, and western blotting (for ERK and Akt). Data were analyzed by the paired Student t-tests and one-way analyses of variance. Cell viability decreased significantly after H2O2 (85%), CoCl2 (50%), and hypoxia chamber (52%) treatments compared to the untreated control (100%). UDCA significantly counteracted the effects of chamber- and CoCl2- induced hypoxia on viability and beating rate. However, no significant differences were observed in acid SMase gene and protein expression between the untreated, CoCl2, and UDCA-CoCl2 groups. In contrast, neutral SMase gene and protein expression did significantly differ between the latter two groups. ERK and Akt phosphorylation was higher in hypoxic cardiomyocytes treated with UDCA than those given CoCl2 alone. In conclusion, UDCA regulates the activation of survival signaling proteins and SMases in neonatal rat cardiomyocytes during hypoxia.

Rodents as reservoir host of intestinal helminthes in different Egyptian agroecosystems

Hymenolepis diminuta were detected in rodents in all zones surveyed Governorates under studied (Suez, Menoufia, Giza, Damietta and Beni-Sewaf). The highest infestation recorded at Suez and Demiatta Governorates. On the other hand, rodents at Menoufia and Beni-Sewaf showed there is no convincing evidence that they infested with H. diminuta. The existence of one species of nematode namely, Streptopharagus kuntzi were recorded at Suez, Giza and Demiatta Governorates only. While Menoufia and Beni-Sewaf Governorates showed no convincing evidence that, they infested with nematode. Worms were recovered from Norway rats. Data indicated that Rattus norvegicus were the most vulnerable species at infection with H. diminuta and Streptopharagus kuntzi. Summer is highly infested with nematode in comparison with other seasonal study.

Congenital malformations in mice induced by addiction to alcohol and cocaine

OBJECTIVE

To study the teratogenic effect of either alcohol alone, cocaine alone, or a combination of both alcohol and cocaine on mice foetuses.

DESIGN

Eighty pregnant mice were divided into four equal groups. In the first (alcohol) group, the pregnant females were given absolute ethanol at 2.5 gm/100 gm twice daily by oro-gastric incubation. In the second (cocaine) group, the pregnant females received cocaine hydrochloride at 20 mg/ 100 gm daily by intraperitoneal injection. In the third (combined) group, the pregnant females received alcohol at 2.5 gm/100 gm twice daily and cocaine hydrochloride at 20 mg/100 gm daily. In all groups the treatment started from the 6th day to the 15th day of gestation. The fourth group is the control.

SETTINGS

Department of Anatomy, College of Medicine, King Faisal University, Dammam, Saudi Arabia and Department of Anatomy, College of Medicine, Al-Azhar University, Cairo, Egypt.

INTERVENTION

The pregnant mice were sacrificed at the 20th day of gestation (one day before term). The uterine contents were evaluated and the number of dead and live foetuses was determined as well as the number of resorption. The living foetuses were examined for soft tissue anomalies.

SUBJECTS

Eighty pregnant mice.

RESULTS

This study revealed a significant increase in the number of dead foetuses and foetal growth parameters showed a significant decrease in the combined group. This group showed significant increase in anomalies of the head as hydrocephaly and complete cleft palate, of the kidney as bilateral secondary hydronephrosis and ectopic kidney, of the limbs, and of the tail as kinked tail. Both alcohol and cocaine groups alone showed significant increase in some of the anomalies of the head while in the alcohol group there was unilateral hydronephrosis.

CONCLUSION

This study indicates that the combined administration of alcohol and cocaine has a more teratogenic effect than either alcohol or cocaine alone.

Circulating Endothelial Cells in Renal Transplant Recipients

Circulating endothelial cells (CECs) are a marker of endothelial injury and endothelial dysfunction. We measured CECs in 95 patients with functioning renal transplants at risk of premature cardiovascular (CV) disease and in normal control subjects. We were unable to demonstrate consistent relationships between CEC levels and conventional CV risk factors in transplant recipients. However, CEC levels were increased in patients with a history of rejection. We conclude that CECs are of little use as a marker of CV risk in this population but may be a useful marker to monitor allograft rejection.

Src-class kinases act within the agrin/MuSK pathway to regulate acetylcholine receptor phosphorylation, cytoskeletal anchoring, and clustering

Synaptogenesis at the neuromuscular junction requires agrin-induced stable localization of acetylcholine receptors (AChRs) at the endplate. The effects of agrin are transduced by the muscle-specific receptor tyrosine kinase (MuSK). This study provides evidence that Src-class protein tyrosine kinases mediate the effects of agrin-activated MuSK to regulate clustering and anchoring of AChRs in skeletal muscle. MuSK was complexed with both Src and Fyn in the C2 mouse muscle cell line. These associations were enhanced by agrin and by increasing protein tyrosine phosphorylation with pervanadate. Coupling between MuSK and the Src-class kinases in vivo appeared to be caused by a phosphotyrosine-SH2 domain interaction because binding of MuSK to the SH2 domains of Fyn and Src in vitro was specific, enhanced by phosphorylation, and dependent on MuSK autophosphorylation. In addition, Src and Fyn phosphorylated MuSK. AChR phosphorylation, stimulated by agrin or pervanadate, was inhibited by blocking Src-class kinases with PP1. Furthermore, agrin-induced clustering and cytoskeletal anchoring of AChRs was dependent on Src-family kinases. These data support the conclusion that Fyn and Src act downstream of MuSK to regulate the stable localization of AChRs at the neuromuscular endplate during agrin-induced synaptogenesis.

Long-term clinical outcome of human immunodeficiency virus-infected patients with discordant immunologic and virologic responses to a protease inhibitor-containing regimen

Within a prospective cohort of 150 human immunodeficiency virus (HIV)-infected patients who began first-line protease inhibitor therapy in 1996, the outcome of 42 patients with discrepant virologic and immunologic responses to antiretroviral treatment at 12 months was analyzed at 30 months of treatment. The incidence of AIDS-defining events and deaths (14%) in the group of patients with immunologic responses in the absence of a virologic response was higher than that in full-responder patients (2%); yet, the incidence in this group was lower than that in patients with no immunologic response, despite a virologic response (21%), and was lower than that in patients without an immunologic or virologic response (67%; P<.0001, log-rank test). Differences in outcome were significant (relative risk, 6.9; 95% confidence interval, 1.9-39.3) when factors for progression were compared with those of responder patients. The results support the relevance of the CD4 cell marker over plasma HIV load for predicting clinical outcome in patients who do not achieve full immunologic and virologic responses.

Generation of phosphorylation state-specific SRC-class kinase antibodies for analysis of kinase activation

Protein phosphorylation is a major molecular mechanism by which cellular function is regulated. In order to accomplish rapid and specific biochemical changes via phosphorylation, the activity of a protein kinase must be dynamically regulated. Historically, the activity of each protein kinase has been analyzed using a unique in vitro biochemical assay with a specific substrate and detection procedure. These assays require the use of radioactivity and are often labor intensive. Upon activation, most protein kinases autophosphorylate. Thus, a technical approach to detect changes in kinase activity is to measure autophosphorylation. The purpose of this protocol is to provide a detailed stepwise procedure for measuring the regulation of Src-class kinase activity using phosphorylation state-specific antibodies. Antibodies to a phosphorylated peptide derived from the autophosphorylation site of Src-family kinases are developed and affinity purified. The purified antibodies are used to analyze the regulation of Src and Fyn activity in a mouse muscle cell line. It is anticipated that the utility of these phosphorylation state-specific antibodies will ultimately result in the development of similar antibodies useful for analyzing the activity of many different kinases.

Post-Transplant Diabetes Mellitus in Kidney Transplant Recipients with Special Reference to Association with HLA Antigens

One hundred fifty three kidney transplant recipients whose grafts functioned for longer than one year were evaluated for evidence of post-transplant diabetes mellitus (PTDM). Twenty-six patients (17%) developed PTDM. Patients with PTDM were older than controls (mean age 49.4 vs 37.9 years). There was no demonstrable association between sex of patients and PTDM. The body mass index (BMI) was persistently higher in patients with PTDM compared to controls, although the difference did not amount to statistical significance. The association of PTDM with HLA-A28, A30 and B8 observed in other studies was not seen in our patients. Similarly, neither the positive association of HLA-DR3 and DR4, nor the negative association of HLA-B7 and DR2 seen in population-based studies of insulin dependent diabetes mellitus, were seen in our patients with PTDM. To our knowledge, this is the first report that has looked into the association of HLA antigens and PTDM in Saudi Arabia.

Skin prick test reactivity to foods in adult Malaysians with rhinitis

The aim of the study was to determine the incidence of food and house dust mite (HDM) allergy in patients with nasal congestion and rhinorrhea attending the Otorhinolaryngology Clinic, National University of Malaysia, Kuala Lumpur. This was a prospective matched, controlled study of patients skin prick tested with commercial food and common aeroallergens. The participants were 148 Malaysian adults with symptoms of nasal congestion and rhinorrhea and 113 adult Malaysian control subjects without rhinitis symptoms. The skin prick test (SPT) was used to evaluate 11 foods common to the Malaysian diet and 3 HDM inhalants. Forty-eight percent of the patients with rhinitis had positive SPT results to foods, compared with 4.4% of control subjects (P < 0.05). The most commonly implicated foods were shrimp (48%) and rice (30%), which are common in the Malaysian diet. Seventy-two percent of rhinitis patients had positive SPT results to HDM, compared with 22.2% of control subjects (P < 0.05). Patients with rhinitis also had significantly more gastrointestinal problems than control subjects (P < 0.05). The incidences of HDM and food allergy are significantly greater in Malaysian adults with rhinitis symptoms than in control subjects without rhinitis. The effect of avoidance or immunotherapy awaits further study.

Effect of the carbamate "aldicarb" on acetyl cholinesterase extracted from whole and different parts of rat brain (in vitro and in vivo studies)

Aldicarb, a synthetic carbamate compound used as an insecticide and herbicide, is also employed as a pharmacological cholinergic agent in therapeutic forms. Inhibition of the enzyme AChE, which results in accumulation of ACh, is the basis for its use as an insecticide and it resulted in toxicity in a variety of animals including man. In this work, experiments were carried out in vitro and in vivo to study the effects of aldicarb on the activity of ChE enzyme extracted from whole and five different parts of rat brain, namely: basal ganglia, frontal cortex, medulla oblongata, pons and cerebellum. Kinetic measurements of Michaelis constants (Km), enzyme inhibitor dissociation constants (Ki) as well as the rate of carbamylation (k2c) and binding constants (Kl) for the inhibition of the enzyme obtained from the different parts were done. The carbamylation rate (degree of inhibition of AChE by carbamate) and binding constant for inhibition of whole and different parts of brain in vitro, indicated that the carbamylation rate constants of pons, medulla oblongata and cerebellum were higher than those of other parts. Inhibition of AChE in the different parts of the brain in vitro by aldicarb was of the competitive type, with different enzyme inhibitor dissociation constants (Ki). In vivo studies showed that the inhibition was marked in the enzyme obtained from pons, medulla oblongata and cerebellum; the parts responsible for vital centers and balance which coinsize with the in vitro results.

Decreasing occupational risk related to blood-borne viruses in cardiovascular surgery in Paris, France

BACKGROUND

Surgeons face the risk of patient-to-physician transmission of blood-borne viruses. This risk is related to the seroprevalence of the viruses in the patient population.

METHODS

The seroprevalence of the human immunodeficiency virus, hepatitis B virus, and hepatitis C virus were determined in cardiovascular patients at Hôpital Broussais in Paris, France, over a 5-year period (1994 to 1998).

RESULTS

Hepatitis C virus is the most prevalent virus in the patient population, whereas human immunodeficiency virus is the least frequent. The seroprevalence of hepatitis C virus and human immunodeficiency virus has decreased over time, whereas hepatitis B virus has remained constant. We apply the seroprevalence data to a mathematical model to estimate the occupational risk of seroconversion faced by surgeons over the length of their career. Our results show that the principal risk faced by the surgeon arises from hepatitis B virus and hepatitis C virus. The decreasing seroprevalence of the hepatitis C virus has resulted in a decrease in the occupational risk.

CONCLUSIONS

The probability of becoming infected with a blood-borne virus over the career of the surgeon is notable. The greatest occupational risk to the surgeon is from the hepatitis viruses and not HIV.

Phosphorylation and cytoskeletal anchoring of the acetylcholine receptor by Src class protein-tyrosine kinases. Activation by rapsyn

Src class protein-tyrosine kinases bind to and phosphorylate the nicotinic acetylcholine receptor of skeletal muscle. This study provided evidence for the functional importance of Src kinases in regulating the nicotinic acetylcholine receptor at the neuromuscular junction. Three Src class kinases, Fyn, Fyk, and Src, each formed a complex with the endplate-specific cytoskeletal protein rapsyn. In addition, cellular phosphorylation by each kinase was stimulated by rapsyn in heterologous transfected cells. Several lines of evidence supported rapsyn as a substrate for Src kinases. Most importantly, rapsyn regulation of Fyn, Fyk, and Src resulted in phosphorylation of the nicotinic acetylcholine receptor beta and delta subunits and anchoring of the receptor to the cytoskeleton. Both nicotinic acetylcholine receptor phosphorylation and cytoskeletal anchoring were blocked by the Src kinase-selective inhibitor herbimycin A. Rapsyn alone also induced a modest increase in nicotinic acetylcholine receptor phosphorylation and cytoskeletal translocation. However, inhibition by herbimycin A and a catalytically inactive dominant negative Src demonstrated that the effects of rapsyn were mediated by endogenous Src kinases. These data support the importance of Src class kinases for stabilization of the nicotinic acetylcholine receptor at the endplate during synaptic differentiation at the neuromuscular junction.

Human herpesvirus 8 infection in patients with POEMS syndrome-associated multicentric Castleman's disease

The polyneuropathy, organomegaly, endocrinopathy, M protein, skin changes (POEMS) syndrome is a rare multisystemic disorder associated with osteosclerotic myeloma and multicentric Castleman's disease (MCD). Human herpesvirus type 8 (HHV-8) DNA sequences have been detected in lymph nodes of about 40% of human immunodeficiency virus (HIV)-negative patients with MCD, and in bone marrow stromal cells of patients with multiple myeloma. Considering these data, we investigated the presence of HHV-8 in 18 patients with POEMS syndrome (9 with MCD), by nested polymerase chain reaction (N-PCR) to detect DNA sequenses in various cells and tissues obtained by biopsy or at autopsy (13 patients, of whom 7 had MCD), and by an immunofluorescence assay to detect anti-HHV-8 IgG antibodies in blood (18 patients, of whom 9 had MCD). Detection of HHV-8 DNA was performed using three different N-PCR, targeting nonoverlapping regions in open reading frame (ORF) 25 and ORF26. Seven of 13 (54%) POEMS patients had HHV-8 DNA sequences in their tissues, as assessed by all three N-PCR, and 9 of 18 (50%) had circulating anti-HHV-8 antibodies. HHV-8 was mainly detected in the subset of POEMS patients with MCD (6 of 7 [85%] for DNA sequences; 7 of 9 [78%] for antibodies). The percentage of positive N-PCR was higher in lymph nodes than in bone marrow samples (P <.02). Sequencing of amplicons showed a homogeneous restricted variability in the ORF26 region, characteristic of the minority subgroup B defined by Zong, and responsible for isoleucine and glycine substitutions at amino acid positions 134 and 167. These findings strongly suggest an association of HHV-8 infection with POEMS syndrome-associated MCD.

Nocardia asteroides in renal transplant recipients

Full text is available as a scanned copy of the original print version.

Parents' awareness and knowledge of the special needs of their hearing-impaired child

We surveyed parents of school-aged hearing impaired children to investigate their awareness and knowledge of the special needs of their child, especially in the area of the usage of hearing aids and methods of communication. Questionnaires were distributed to parents of hearing impaired children at 13 special schools for the deaf in Malaysia. Out of 1,267 questionnaires given out, 787 (62.1%) were completed and returned. Results of the survey indicated the majority of parents (68.6%) suspected hearing loss late, that is after their child's first birthday, and there was a significant time lag before the suspicion was confirmed. Over 82.8% of the children were diagnosed only after 1 year of age, with 41.3% being diagnosed after 3 years of age. Hearing aids were fitted late (mean = 5.32 years; SD = 2.66). Hearing aid ownership was influenced by the factors of socio-economic level and ethnic group (p < 0.01) whereas knowledge of use and proper care of the aids was influenced by socio-economic level (p < 0.01). Communication methods were generally inappropriate with 41.3% of the mothers and 48.5% of the fathers reporting ignorance of Bahasa Malaysia Kod Tangan, the sign language that is commonly used by their children. The parents' choice of communication method was not significantly influenced by socio-economic level or ethnic group. The study revealed the present inadequate state of services available for the rehabilitation of children with congenital hearing impairment.

Cardiac myosin-binding protein C (MyBP-C): identification of protein kinase A and protein kinase C phosphorylation sites

Myosin binding protein C (MyBP-C) is a major myofibril-associated protein in cardiac muscle which is subject to reversible phosphorylation. Cardiac MyBP-C is a substrate in vivo and in vitro for cAMP-dependent protein kinase (PKA) and calcium/phospholipid-dependent protein kinase (PKC). Chicken cardiac MyBP-C was phosphorylated by PKA to 3.0 mol phosphate/mol and by PKC to 2.0 mol phosphate/mol. Tryptic phosphopeptides from MyBP-C were purified by successive iron iminodiacetate column chromatography and reversed-phase high-performance liquid chromatography. Three phosphopeptides purified from PKA-phosphorylated MyBP-C contained phosphoserine [T1, (RTS[P]LAGGGR) and T2, (KRDS[P]FLR)] or phosphothreonine (CT3, MT[P]SAFL). PKC phosphorylated two of the same sites (T1 and T2) as PKA and an additional site [T2a (TGTTYKPPS[P]YK)]. PKA phosphorylation sites corresponding to peptides T1, T2, and T3 were identified in the N-terminus of the cDNA deduced amino acid sequence (S265, S300, and T274, respectively). The PKC-specific site in peptide T2a was at position S1169. cDNA clones encoding rat cardiac MyBP-C were isolated, and the segment corresponding to PKA and major PKC phosphorylation sites was sequenced. Chicken cardiac MyBP-C has a threonine at position 274 (CT3), whereas rat cardiac MyBP-C has a serine at the corresponding position. Only chicken cardiac MyBP-C had a phosphorylatable residue at the position corresponding to S1169. All of the cardiac MyBP-C phosphorylation sites are absent in known sequences of skeletal muscle MyBP-C isoforms.

Myoglobin as a polymerase chain reaction (PCR) inhibitor: a limitation for PCR from skeletal muscle tissue avoided by the use of Thermus thermophilus polymerase

Skeletal muscle tissue contains polymerase chain reaction (PCR) inhibitors that are coextracted by conventional nucleic acid extraction procedures. Myoglobin, a heme-containing molecule, was shown to act as a potent Thermus aquaticus DNA polymerase inhibitor and is likely to be involved in muscle tissue-associated PCR inhibition. The use of Thermus thermophilus DNA polymerase avoids muscle tissue-associated PCR inhibition, and should be used in case of small amounts or instability of the targeted nucleic acid.

Dilution assessment of cervicovaginal secretions collected by vaginal washing to evaluate mucosal shedding of free human immunodeficiency virus

A 10 mM concentration of lithium does not interfere with reverse transcription (RT) or PCR. Sampling of cervicovaginal fluid by vaginal washing, with lithium (10 mM) in the washing buffer as a marker of dilution, may be utilized to accurately determine in HIV-infected women, by quantitative RT-PCR, the genital shedding of acellular HIV RNA at the level of the mucosa itself.

Free living amoebae as opportunistic parasites in immunocompromised hosts

The acquisition of invasiveness of mammalian tissue by free living amoebae (FLA) is an extremely noteworthy phenomenon. Many factors may be responsible for this evolutionary change in their physiology. The present work aimed to clarify the host factors in this problem. Albino mice were the laboratory animals used in this work. Non-pathogenic strains of FLA were isolated from ear, nose and pharyngeal swabs and from contact lenses of patients attending out patient clinics in Benha University Hospitals. Isolation was done by cultivation of non-nutrient agar at 37 & 43 degrees C and identification was made by flagellation test. The degree of pathogenicity of isolated strains was assessed by using animal pathogenicity test. Endoxan (0.7 mg/kg) and Prednisolone (2 mg/kg) were used for 15 days orally to suppress the immunity of clean mice before their inoculation intranasally with the isolated strains. All groups were observed for 3 weeks post-infection. Mortality rates recorded were higher in Endoxan or Prednisolone treated and Naegleria infected groups A I & B I (20 & 15% respectively) than Endoxan or Prednisolone treated and acanthamoeba infected groups A II & B II (10%) and drug control (10%). Histopathological examination of brain and meninges revealed severe changes in form of severe meningoencephalitis, severe vacuolar degeneration, and moderate haemorrhage and necrosis in brains of groups AI & BI and less severe changes in groups AII & BII (10%) form of-non granulomatous encephalitis. Drug control groups showed negligible changes. Great attention must be paid to reveal the presence of FLA before using immunosuppressive drugs in human cases.

[Sequences of human herpes virus type 8 and Epstein-Barr virus in AIDS-related primary central nervous system non-Hodgkin's lymphoma]

Presence of human herpes virus type 8 (HHV8), detected by nested PCR, and expression of Epstein-Barr virus (EBV), as assessed by immunochemistry and in situ hybridization, were evaluated in 20 primary non-Hodgkin immunoblastic lymphomas (NHL) of the central nervous system (CNS) from patients who died from AIDS, and in 10 samples of cerebral tissues from patients who died from AIDS, without cerebral lymphoma or Kaposi's sarcoma, as controls. Six lymphomas (30%) contained HHV8 sequences, and 19 (95%) expressed EBV; detection of HHV8 was more frequent in patients with Kaposi's sarcoma, than in other subjects (4/6 versus 2/14). Three (30%) controls contained HHV8 sequences, whereas none expressed EBV. AIDS-related CNS NHL is therefore clearly associated with EBV expression, while the presence of HHV8 appears occasional, probably associated with a low tissue viral load. The high frequency of HHV8 in AIDS-related primary CNS NHL patients with Kaposi's sarcoma suggests that this virus could play a role in the pathogenesis of some cerebral lymphomas.

Gamma knife pallidotomy: case report

We report a case of gamma knife pallidotomy resulting in a permanent contralateral homonymous hemianopsia and transient contralateral hemiparesis with some improvement in contralateral parkinsonian symptoms. This case illustrates the risk of gamma knife pallidotomy which precludes physiologic target localization and can subject structures surrounding the target to a significant radiosurgical dose. Until noninvasive physiologic target localization is available gamma knife pallidotomy and thalamotomy should be limited to patients with an unacceptably high risk for stereotactic percutaneous thermocoagulation.

Electrophysiologic target localization in posteroventral pallidotomy

The current interest in stereotactic posteroventral pallidotomy (PVP) for treating Parkinson's disease and the variability of published results have raised questions regarding techniques for target localization. In our technique the probe is guided to the optimum target at the most ventral pallidum and ansa lenticularis by macroelectrode stimulation of the internal capsule and optic tract from within the globus pallidus, with the thresholds providing a relative measure of the electrode proximity to these structures. We have characterized these localizing macroelectrode stimulation parameters in 57 posteroventral pallidotomies with consistent anatomic lesion placement, excellent outcome, and no complications. Using a 1.8 x 2.0 mm radiofrequency electrode for macroelectrode stimulation (RFG-3C, Radionics Inc.), minimum voltages (thresholds) to activate motor (at a frequency of 2 Hz) or visual (at a frequency of 100 Hz) responses as well as impedance measurements were obtained at the final target (Tf) and at distances proximal to Tf along the electrode trajectory. The visual and motor threshold voltages at Tf via our standard approach angles (50 degrees above base plane, 20 degrees from the sagittal plane), had a range of 1.0 to 1.5 V, and 2.0 to 3.5 V respectively. We also found that as the probe approaches Tf there is a significant decrease in voltage thresholds for motor (P < .0001) and visual (P < .0001) responses in an individual patient indicating that the probe is converging on these structures. Increases in impedance between Tf, 2-3 mm, and 4-5 mm proximal to Tf were also statistically significant (P < .0001). Microelectrode recording to electrophysiological neuronal activity at various points along the trajectory towards the target showed distinct firing patterns providing identification of the globus pallidus externus and internus, ansa lenticularis, and optic tract. Macroelectrode electrophysiological stimulation within the target volume, inducing threshold responses in the internal capsule and optic tract, provides for accurate localization of the most effective PVP target in the ansa lenticularis. In unresponsive patients, the utilization of microelectrode recording for the identification of the pallidal borders and the optic tract improves safety.

Normalization of middle latency auditory P1 potential following posterior ansa-pallidotomy in idiopathic Parkinson's disease

The P1 potential (50 msec) of middle latency auditory evoked potential was evaluated in seven patients with advanced idiopathic Parkinson's disease before and after contemporaneous bilateral posterior ansa-pallidotomy. P1 potential was lacking in two patients preoperatively and was prolonged in the remainder of the patients when examined in a best medicated 'on' state. All patients showed varying degrees of dementia preoperatively on clinical examination. Remarkable improvement in their Unified Parkinson's Disease Rating Scale (UPDRS) scores during 'on' states from a mean of 45.85 to 14.28 post-operatively was achieved. Subsidence of akinetic symptoms, abolishment of dyskinesia, improvement in gait freezing, rigidity, and tremors represented main areas of improvement. P1 latencies and amplitudes reverted back to normal values in six patients including the two patients who lacked P1 wave preoperatively. One patient showed mild worsening of both Pa and P1 values post-operatively attributed to sleepiness during testing, a transient phenomenon commonly encountered following posterior ansa-pallidotomy. The post-operative P1 changes were statistically significant for both latencies and amplitudes at p = 0.078 and p = 0.073, respectively, for all seven patients using one tailed paired t-test. The change in UPDRS post-operatively best correlated with the post-operative difference in P1; specifically, UPDRS subscore II with P1 amplitude (r = -0.068, p = 0.09), and UPDRS subscore IV with Pa: P1 ratio (r = +0.77, p = 0.04). Earlier clinical and experimental work support the tegmental pedunculopontine nucleus (PPN) as the site of origin of P1 wave. In addition, its presence reflects the integrity of output cholinergic projection from PPN to both ascending reticular activating system ARAS and auditory pathway. We believe this is the first report of restoring the integrity of P1 wave following posterior ansa-pallidotomy in patients with advanced idiopathic Parkinson's disease. Disinhibition of the PPN by posterior ansa-pallidotomy can explain improvements in motor symptoms in view of reemergence and normalization of P1 wave form.

Cervicovaginal synthesis of IgG antibodies to the immunodominant 175-199 domain of the surface glycoprotein gp46 of human T-cell leukemia virus type I

Paired sera, saliva and cervicovaginal secretions from 17 HTLV-I-infected women (19-75 yr) were tested for total IgA and IgG, for IgA and IgG to the immunodominant region gp46/175-Pro-199, for serum IgG to the neutralizing domains gp46/ 190-Pro-199 and gp46/190-Ser-199, or for tax-rex proviral HTLV-DNA. Serum antibodies to gp46/ 175-Pro-199 were detected more frequently in the IgG (13/17) than in the IgA (5/17) isotypes. The majority (8/12) of anti-gp46/175-Pro-199-positive sera reacted also to gp46/190-Pro-199 or to gp46/ 190-Ser-199, demonstrating their neutralizing properties. In saliva, antibodies to gp46/175-Pro-199 were not generally detected. In cervicovaginal secretions, IgG to gp46/175-Pro-199, but not IgA, were detected in 6/15 (40%) patients. The mean specific activity of IgG to gp46/175-Pro-199 showed a trend to be higher in cervicovaginal secretions (218 +/- 109) than in sera (14 +/- 4). Furthermore, in all patients with cervicovaginal IgG to gp46/175-Pro-199, the cervicogaginal/serum ratio (19 +/- 6) of anti-gp46 IgG specific activities were markedly above 1. HTLV-DNA was detected in 4/17 salivas, and in 3/15 cervicovaginal secretions, all from patients demonstrating cervicovaginal synthesis of IgG to gp46/175-Pro-199. In conclusion, IgG to gp46/175-Pro-199 in cervicovaginal secretions, when present, appear to be produced primarily locally because of local HTLV-I excretion. Since anti-gp46/175-Pro-199 antibodies usually support reactivities to neutralizing domains, their presence could be relevant for limiting HTLV-I transmission via cervicovaginal secretions.

Comparison of cervicovaginal humoral immunity in clinically asymptomatic (CDC A1 and A2 category) patients with HIV-1 and HIV-2 infection

Paired sera and cervicovaginal secretions (CVS) from 11 HIV-1- and 11 HIV-2-infected women, all clinically asymptomatic (CDC A1 and A2 categories), were analyzed for total IgG, IgA, albumin (HSA), IgG, and IgA antibodies to env-encoded surface glycoproteins of HIV-1 (gp160) and of HIV-2 (gp105), by comparison to 15 age-matched healthy controls. Secretion rates of IgG and IgA into CVS were evaluated by calculation of their relative coefficients of excretion (RCE) by reference to HSA. Cervicovaginal production of anti-HIV antibodies was evaluated by comparison between specific antibody activities of IgG and of IgA to HIV in CVS were, respectively, 6- and 4-fold increased, whereas the secretion rate of total IgG was 2.1-fold increased and that of total IgA was 2.5-fold reduced. In contrast, total IgG and IgA as well as their secretion rates were normal in HIV-2-infected women. In HIV-1- but not in HIV-2-infected women, HSA levels in cervicovaginal washings were twofold increased, demonstrating alteration of the mucosal barrier in HIV-1 infection. In HIV-1-infected patients, IgG and IgA to gp160 were detected in all sera and CVS. In HIV-2-infected patients, IgG to gp105 was detected in all sera and CVS, whereas IgA to gp105 could be detected in only half of sera and one-third of CVS. Cross-reactivity by IgG and/or IgA to HIV-1 or HIV-2 against the surface glycoprotein of the other HIV type was observed in sera as well as in CVS, and more frequently in HIV-2- than in HIV-1-infected women. Finally, the mean specific activities of IgG and of IgA to gp160 or gp105 were higher in CVS than in sera, evidencing a possible local synthesis of both isotypes in HIV-1 as well as in HIV-2 infections. As early as the asymptomatic stages, HIV-1 affects the cervicovaginal mucosa more than HIV-2 does, suggesting higher viral replication within the female genital tract in HIV-1 infection than in HIV-2 infection.

Cervicovaginal anti-HIV antibodies in index women from HIV-discordant, exclusively heterosexual, couples

Cervicovaginal IgA and IgG anti-gp160 antibodies were evaluated in cervicovaginal secretions from twelve HIV-discordant heterosexual couples, matched with twelve HIV-concordant heterosexual couples, at similar stage of HIV disease. The mean reciprocal end-point titers of cervicovaginal IgA or IgG to gp160 were similar in cases and in controls. These observations suggest that cervicovaginal antibodies to HIV do not appear as biological indicators sufficiently relevant to explain a possible reduced infectivity of the female index case in HIV-discordant couples, by comparison with HIV-concordant couples.

Experience with sublabial transseptal transsphenoidal hypophysectomy at the Universiti Kebangsaan Malaysia

The transseptal transsphenoidal hypophysectomy has become a relatively frequent procedure in recent years. We performed 20 such procedures between January 1984 and December 1987 for various pituitary disorders. Significant complications such as CSF rhinorrhea, meningitis, diabetes insipidus, haemorrhage and septal perforation are discussed. The mortality rate for the series was 5%. In analysing the data, we feel that this technique of hypophysectomy is a safe procedure.

Lack of intrinsic activity and significant subtype selectivity of SR 95639A at muscarinic receptors

We assessed the intrinsic activity of the purported selective muscarinic M1 receptor agonist SR 95639A (morpholinoethylamino-3-benzocyclohepta-(5,6-c)-pyridazine) in inducing several receptor-mediated signals. Our results indicate that SR 95639A lacks the ability to activate phosphoinositide hydrolysis in rat cerebral cortex or in Chinese hamster ovary cells transfected with the genes of the muscarinic m1 and m3 receptors. Similarly, this compound did not exhibit intrinsic activity in stimulating muscarinic receptors which inhibit cyclic AMP synthesis and did not suppress acetylcholine release in rat striatum. In addition, SR 95639A did not show a marked selectivity at the level of the ligand recognition site at the muscarinic M1, M2 and M3 receptors, since it bound to these receptor subtypes with equilibrium dissociation constants of 4, 6 and 11 microM, respectively.

Treatment time for Amersham caesium-137 manual afterloading system

Currently, the Amersham caesium-137 afterloading system is widely used for gynecological treatment of tumors in uterine cervix. This paper introduces an expert system to determine the time of exposure of an Amersham afterloading system based on different combinations of applicator sources. The efficiency of the expert system achieves 93% of the clinical decisions taken by physicians. It is evaluated by both the experimental results and the actual clinical decisions.