First-in-Class Humanized Antibody against Alternatively Spliced Tissue Factor Augments Anti-Metastatic Efficacy of Chemotherapy in a Preclinical Model of Pancreatic Ductal Adenocarcinoma

Alternatively spliced tissue factor (asTF) promotes the progression of pancreatic ductal adenocarcinoma (PDAC) by activating β1-integrins on PDAC cell surfaces. hRabMab1, a first-in-class humanized inhibitory anti-asTF antibody we recently developed, can suppress PDAC primary tumor growth as a single agent. Whether hRabMab1 has the potential to suppress metastases in PDAC is unknown. Following in vivo screening of three asTF-proficient human PDAC cell lines, we chose to make use of KRAS G12V-mutant human PDAC cell line PaCa-44, which yields aggressive primary orthotopic tumors with spontaneous spread to PDAC-relevant anatomical sites, along with concomitant severe leukocytosis. The experimental design featured orthotopic tumors formed by luciferase labeled PaCa-44 cells; administration of hRabMab1 alone or in combination with gemcitabine/paclitaxel (gem/PTX); and the assessment of the treatment outcomes on the primary tumor tissue as well as systemic spread. When administered alone, hRabMab1 exhibited poor penetration of tumor tissue; however, hRabMab1 was abundant in tumor tissue when co-administered with gem/PTX, which resulted in a significant decrease in tumor cell proliferation; leukocyte infiltration; and neovascularization. Gem/PTX alone reduced primary tumor volume, but not metastatic spread; only the combination of hRabMab1 and gem/PTX significantly reduced metastatic spread. RNA-seq analysis of primary tumors showed that the addition of hRabMab1 to gem/PTX enhanced the downregulation of tubulin binding and microtubule motor activity. In the liver, hRabMab1 reduced liver metastasis as a single agent. Only the combination of hRabMab1 and gem/PTX eliminated tumor cell-induced leukocytosis. We here demonstrate for the first time that hRabMab1 may help suppress metastasis in PDAC. hRabMab1's ability to improve the efficacy of chemotherapy is significant and warrants further investigation.

Transseptal puncture for left atrial ablation: risk factors for cardiac tamponade and a proposed causative classification system

Aims

Cardiac tamponade is a high morbidity complication of transseptal puncture (TSP). We examined the associations of TSP‐related cardiac tamponade (TRCT) for all patients undergoing left atrial ablation at our center from 2016 to 2020.

Methods and Results

Patient and procedural variables were extracted retrospectively. Cases of cardiac tamponade were scrutinized to adjudicate TSP culpability. Adjusted multivariate analysis examined predictors of TRCT. A total of 3239 consecutive TSPs were performed; cardiac tamponade occurred in 51 patients (incidence: 1.6%) and was adjudicated as TSP‐related in 35 (incidence: 1.1%; 68.6% of all tamponades). Patients of above‐median age [odds ratio (OR): 2.4 (1.19–4.2), p = .006] and those undergoing re‐do procedures [OR: 1.95 (1.29–3.43, p = .042] were at higher risk of TRCT. Of the operator‐dependent variables, choice of transseptal needle (Endrys vs. Brockenbrough, p > .1) or puncture sheath (Swartz vs. Mullins vs. Agilis vs. Vizigo vs. Cryosheath, all p > .1) did not predict TRCT. Adjusting for operator, equipment and demographics, failure to cross the septum first pass increased TRCT risk [OR: 4.42 (2.45–8.2), p = .001], whilst top quartile operator experience [OR: 0.4 (0.17–0.85), p = .002], transoesophageal echocardiogram [TOE prevalence: 26%, OR: 0.51 (0.11–0.94), p = .023], and use of the SafeSept transseptal guidewire [OR: 0.22 (0.08–0.62), p = .001] reduced TRCT risk. An increase in transseptal guidewire use over time (2016: 15.6%, 2020: 60.2%) correlated with an annual reduction in TRCT (R² = 0.72, p < .001) and was associated with a relative risk reduction of 70%.

Conclusions

During left atrial ablation, the risk of TRCT was reduced by operator experience, TOE‐guidance, and use of a transseptal guidewire, and was increased by patient age, re‐do procedures, and failure to cross the septum first pass.

QT interval in patients receiving HCQ in SARS-CoV-2- A study on risk factors and correlation of baseline QTc with delta QTc in Pakistani population

Funding Acknowledgements

Type of funding sources: None.

Introduction

Hydroxychloroquine(HCQ) use alone or in combination with Azithromycin (AZM) in SARS-CoV-2 infection is associated with QTc prolongation and risk of arrhythmias.

Objectives

To determine changes in QTc interval and factors predictive of extreme QTc prolongation in patients receiving HCQ alone or in azithromycin combination in Pakistani patients.

Methodology

Retrospective review of records of hospitalized patients with SARS-Cov2 RT-PCR positive result who received HCQ or HCQ/Azithromycin in combination from March-May 2020. Baseline ECGs as well as post drug use ECGs data was recorded. Tisdale score was calculated for predicting risk of QTc prolongation,QTc interval was calculated using Bazett formula. Data entry and analysis was done in SPSS version 23. 

Results

A total of 134 patients were included in the study.  82.1%(110) were males and 17.9%(24) were females, mean age was 54.9 ± 13.7 years. 61.2% (82) had severe disease and 38.8 %(52) had non-severe disease. 14.2%(19) had history of cardiac disease, 35.8%(48) had hypertension and 35.1%(47) had diabetes mellitus. 70.1% (94) patients had received HCQ, AZM, or HCQ/AZM in combination. 40(29.9%) patients had not received any drug. Median baseline QTc among controls and non-control group was 383.5 (IQR 342.25-413.75)msec  and 379(IQR 358-402)msec respectively. HCQ alone was administered to 26.9%(36) and HCQ/AZM to 33.6%(45) patients. 55.6% (45/81) developed QTc prolongation(QTc> 480 msec) or delta QTc increase > 60 msec. 6.2%(5/81) had absolute QTc > 500 msec post-drug administration. 55.6%(25/45) and  30.6%(11/36) (p-value 0.024) developed QTc prolongation in combination and HCQ alone groups respectively. Delta QTc increased to >60msec in 42.0% (34/81); 53.3%(24/45) in  combination group and in 27.8%(10/36) of those receiving HCQ alone( p-value 0.021). Median delta change was 63( IQR 25-81) and 48.5(IQR 26.25-66.75) msec; Median Day 2 QTc  was 413.5 msec (IQR 377.5-436) and 413 msec (IQR361-447); and median maximum QTc was 447(IQR391-471) and 429.8(IQR401.5-45.75) msec in those receiving HCQ/AZM combination and HCQ alone respectively. 9%(12/134) had arrhythmias during hospital stay, in  8.9% (4) and 5.6%(2) patients of those receiving HCQ/AZM combination and HCQ alone respectively, no patient developed torsade de pointes, one patient had non-sustained VT. There was no statistically significant association of QTc prolongation  with mortality, acute kidney injury, myocardial injury or severity of disease. Diuretic use was found to be statistically significant association with QTc prolongation(p-value 0.038). There was a weak correlation of baseline QTc with Δ QTc(r = 0.207 and p-value 0.017)

Conclusion

QTc prolongation was observed in a significant population of patients receiving HCQ and HCQ/AZM combination, however, no significant life threating arrhythmias occurred.

P504VT ablation outcomes and predictors in a UK population- validating existing predictors and novel markers

Background

Radiofrequency catheter ablation (CA) can reduce ventricular tachycardia (VT) burden and registry data suggests an improvement in mortality. However, there is significant heterogeneity in patient morbidity and VT phenotype. A risk prediction model derived from observational data has suggested pre-procedural left ventricular (LV) function, age and underlying ischaemic cardiomyopathy are associated with greater post-procedural mortality. Validation of proposed factors in clinical practice is required to facilitate comprehensive pre-procedural risk stratification and inform decision making.

Purpose

To determine whether proposed pre-procedural predictors of mortality after VTCA are valid in a UK population and explore any association with other predictors.

Method

Patients undergoing VTCA at a tertiary electrophysiology centre between 06/07/16 and 31/07/19 were included. Pre-specified characteristics and mortality follow-up data were analysed from electronic health records. Cox regression analysis was undertaken to determine association with mortality.

Results

161 patients with mean age of 63 ±15.9 years underwent VTCA of whom 133 (83%) were male. During the follow-up  period (16 months, 13-24; median, 1st-3rd quartile) 16 patients died. No deaths occured in the 27 (16%) patients with structurally normal hearts. Chronic kidney disease (CKD) stage III-IV (HR 14.73 [4.9-44.4]), LV ejection fraction &lt;35% (HR 7.13 [1.59-31.88]), underlying ischaemic cardiomyopathy (HR 6.17 [1.37-27.85]), LV internal diameter (LVID) (1.08 [1.02-1.15]) and age (HR 1.08 [1.02-1.14]) were associated with significantly greater mortality risk (Table 1) (Figure 1).

Conclusion

Proposed risk stratifying factors are validated in our UK centre’s experience. Additionally, CKD and baseline LVID appear to be associated with mortality in our population and warrant further study.

Risk factor Hazard ratio Lower confidence interval Upper confidence interval P-value Atrial fibrillation (yes/no) 0.14 0.02 1.11 0.06 Age (years) 1.08 1.02 1.14 &lt;0.01 Diabetes (yes/no) 2.43 0.85 6.92 0.10 Chronic kidney disease (yes/no) 14.73 4.88 44.41 &lt;0.01 Ischaemic cardiomyopathy (yes/no) 6.17 1.37 27.85 0.02 LV EF &lt;35% (yes/no) 7.13 1.59 31.88 &lt;0.01 LV internal diameter (mm) 1.08 1.02 1.15 &lt;0.01 Procedural urgency (urgent/elective) 1.12 0.57 2.20 0.75 Table 1: Association between baseline risk factors and mortality risk after VT catheter ablation

Abstract Figure 1: Kaplan-Meier survival curves

126Dynamic high density functional substrate mapping improves outcomes in ventricular tachycardia ablation

Introduction

Activation and entrainment mapping of VT remains the gold standard for identifying critical sites for ablation of VT, however, this method is limited by poorly tolerated or non-sustained VT. Several substrate guided approaches have been developed, however, outcomes when comparing both methods are similar and overall success can be as low as 47%. A key element in facilitating VT is the presence of dynamic changes within the substrate which may not be evident during sinus rhythm substrate mapping, but may form a critical aspect of the tachycardia mechanism when conduction velocity slows dynamically and tissue refractory periods lengthen. These are rarely studied as part of clinical VT mapping. 

Purpose

This study aimed to investigate dynamic substrate changes to local abnormal ventricular activity (LAVA) and late potentials (LP), in relation to critical sites for VT ablation using high resolution mapping of the ventricle with the HD Grid (Abbott, Inc, USA), during short coupled singe extra stimuli from the right ventricle (RV) (Barts Sense Protocol), designed to invoke conduction delay. We hypothesized that the dynamic functional late potential mapping would improve the identification of critical substrate and ablation of these regions would improve outcomes. 

Methods

Thirty patients (age 67 +/- 9yrs, 27Male) underwent ablation. Mean ejection fraction was 25% (+/- 10%). Mapping was performed with the AdvisorTM HD Grid multipolar catheter. A bipolar voltage map was obtained during sinus rhythm (SR) and RV Sensed Protocol (SP) single extra pacing. SR and SP late potential (LP) and local abnormal ventricular activity (LAVA) maps were made and compared with critical sites for ablation, defined as sites of best entrainment or pace mapping. Ablation was then performed to critical sites and LP/LAVA identified by the SP.

Results

At a median follow up of 10 months 90% of patients were free from symptomatic ATP or ICD shocks. The median area of late potentials across the 30 patients during sinus rhythm was 6.4mm2 during sinus rhythm mapping and 19.3mm2 during sense protocol pacing (p = 0.001). The functional unmasking of LP and LAVA was seen in 26 patients and showed good correlation to critical regions of the VT circuit (sites of best entrainment or pace map). In 24 patients functionally unmasked late potentials were located within 10mm of critical regions within the mapped VT circuit, with a median distance of 8.5mm, compared to 7 patients during sinus rhythm mapping with a median distance of 22mm (p= &lt;0.001). Figure 1 demonstrates and example of the SP, where increased functional LP are seen along the mapped VT isthmus. 

Conclusion

Functional LP and LAVA can be unmasked by the sense protocol enabling better delineation of critical regions for VT ablation which may not be visible during sinus rhythm. This unique delineation of functional substrate changes combined with activation or pacemapping may improve outcomes.

Abstract Figure 1

Initial experience with the convergent procedure for longstanding persistent atrial fibrillation: A 5 year dataset

In patients with longstanding persistent atrial fibrillation (AF), outcomes from catheter ablation remain suboptimal. The convergent procedure combines minimally invasive surgical ablation with subsequent catheter ablation, and may contribute towards maintenance of sinus rhythm in this patient group. We performed the convergent procedure on 43 patients with longstanding persistent AF from 2013–2018. Patients underwent clinical review at 3, 6, and 12 months and thereafter as necessitated by their symptoms. Our dataset describes patients’ baseline characteristics and rhythm control protocols, as well as outcomes including arrhythmia recurrence, the need for antiarrhythmic drugs, requirement for repeat rhythm control procedures, and complications. These data provide a real world insight into the risks and benefits of the convergent procedure in patients with longstanding persistent AF.

Welfare Assessment of Dairy Cows in Small Farms in Bangladesh

Protocols for assessing the welfare of dairy cows in large scale intensive dairy systems in the developed world have been used extensively. Little attention has been paid to the use of similar welfare assessment protocols for small dairy enterprises in developing countries. We modified part of the standard assessment protocol and used it to assess aspects of the welfare of dairy cows in a field survey of 70 small farms in the Sirajgonj district of Bangladesh. Welfare indicators selected were mainly those of health and economic importance, such as lameness, lesions on the body and limbs, cleanliness levels, milk yield, and body condition. The study included physical examination of 700 cows and use of a structured questionnaire to collect data on health and management practices and farmers' perspectives about animal welfare. Mean milk yield, averaged across farms, was 10.3 L/d (range 6.3-14.2) and body condition assessment indicated that cows were, on average, thin. Hygiene management was often poor, with soiling of body parts with faeces. The prevalence of lameness, at 4.3%, was less than has commonly been observed in larger, more intensive dairy farms, but body injuries were commonly detected at the carpal and hock joints (56 and 51% of cows, respectively). This suggests that floors and/or bedding to lie on were inadequate. Many farmers did not follow routine vaccination and deworming schedules (63% and 31%, respectively) and farmers were not generally aware of the concept of animal welfare. The study demonstrates some similar welfare issues to those that have been commonly identified in large, intensive units, but also some differences, in particular a failure to provide good floors, bedding, and basic health care.

Five-year survival outcomes for patients with advanced melanoma treated with pembrolizumab in KEYNOTE-001

BACKGROUND

Pembrolizumab demonstrated robust antitumor activity and safety in the phase Ib KEYNOTE-001 study (NCT01295827) of advanced melanoma. Five-year outcomes in all patients and treatment-naive patients are reported herein. Patients whose disease progressed following initial response and who received a second course of pembrolizumab were also analyzed.

PATIENTS AND METHODS

Patients aged ≥18 years with previously treated or treatment-naive advanced/metastatic melanoma received pembrolizumab 2 mg/kg every 3 weeks, 10 mg/kg every 3 weeks, or 10 mg/kg every 2 weeks until disease progression, intolerable toxicity, or patient/investigator decision to withdraw. Kaplan-Meier estimates of overall survival (OS) and progression-free survival (PFS) were calculated. Objective response rate and PFS were based on immune-related response criteria by investigator assessment (data cut-off, September 1, 2017).

RESULTS

KEYNOTE-001 enrolled 655 patients with melanoma; median follow-up was 55 months. Estimated 5-year OS was 34% in all patients and 41% in treatment-naive patients; median OS was 23.8 months (95% CI, 20.2-30.4) and 38.6 months (95% CI, 27.2-not reached), respectively. Estimated 5-year PFS rates were 21% in all patients and 29% in treatment-naive patients; median PFS was 8.3 months (95% CI, 5.8-11.1) and 16.9 months (95% CI, 9.3-35.5), respectively. Median response duration was not reached; 73% of all responses and 82% of treatment-naive responses were ongoing at data cut-off; the longest response was ongoing at 66 months. Four patients [all with prior response of complete response (CR)] whose disease progressed during observation subsequently received second-course pembrolizumab. One patient each achieved CR and partial response (after data cut-off). Treatment-related AEs (TRAEs) occurred in 86% of patients and resulted in study discontinuation in 7.8%; 17% experienced grade 3/4 TRAE.

CONCLUSIONS

This 5-year analysis of KEYNOTE-001 represents the longest follow-up for pembrolizumab to date and confirms the durable antitumor activity and tolerability of pembrolizumab in advanced melanoma.

CLINICAL TRIAL REGISTRY

ClinicalTrials.gov, NCT01295827.

Anti-Phospholipid Antibody Syndrome with Subdural Hematoma: A Case Report

A 33-year-old man with anti-phospholipid antibody syndrome associated with Budd Chiari syndrome and subdural hematoma. He developed venous thrombosis in his hepatic vein (stenting done) when laboratory studies demonstrated prolongation of activated partial thromboplastin time (APTT). Subdural hematoma demonstrated with Computed tomography (CT) of brain. Laboratory studies revealed thrombocytopenia, prolonged bleeding time and APTT, positive antinuclear antibody and positive test results for both lupus anticoagulant and an anti-cardiolipin antibody, namely antiphospholipid antibodies. Based on these findings, we consider that the tendency of this bleeding may have been due to antiphospholipid antibodies, attacking the platelet membranes and that the bridging veins in the subdural space may be the site at which the bleeding tendency easily appears. Antiphospholipid antibody syndrome accompanied by hemorrhagic complications had rarely been reported. We suggest that special attention should be given to hemorrhagic complications in patients with antiphospholipid antibody syndrome associated with fragility of the vessels and/or platelet dysfunction and on anticoagulant (warfarin).Pulse Vol.10 January-December 2017 p.25-28

Impact of attributed audit on procedural performance in cardiac electrophysiology catheter laboratory

PURPOSE

Audit has played a key role in monitoring and improving clinical practice. However, audit often fails to drive change as summative institutional data alone may be insufficient to do so. We hypothesised that the practice of attributed audit, wherein each individual's procedural performance is presented will have a greater impact on clinical practice. This hypothesis was tested in an observational study evaluating improvement in fluoroscopy times for AF ablation.

METHODS

Retrospective analyses of fluoroscopy times in AF ablations at the Barts Heart Centre (BHC) from 2012-2017. Fluoroscopy times were compared pre- and post- the introduction of attributed audit in 2012 at St Bartholomew's Hospital (SBH). In order to test the hypothesis, this concept was introduced to a second group of experienced operators from the Heart Hospital (HH) as part of a merger of the two institutions in 2015 and change in fluoroscopy times recorded.

RESULTS

A significant drop in fluoroscopy times (33.3 ± 9.14 to 8.95 ± 2.50, p < 0.0001) from 2012-2014 was noted after the introduction of attributed audit. At the time of merger, a significant difference in fluoroscopy times between operators from the two centres was seen in 2015. Each operator's procedural performance was shared openly at the audit meeting. Subsequent audits showed a steady decrease in fluoroscopy times for each operator with the fluoroscopy time (min, mean±SD) decreasing from 13.29 ± 7.3 in 2015 to 8.84 ± 4.8 (p < 0.0001) in 2017 across the entire group.

CONCLUSIONS

Systematic improvement in fluoroscopy times for AF ablation procedures was noted byevaluating individual operators' performance. Attributing data to physicians in attributed audit can promptsignificant improvement and hence should be adopted in clinical practice.

Clinical Profile and Outcome of Intracranial Meningioma in Apollo Hospitals Dhaka

Background: A meningioma is a tumor that arises from the meninges- the membranes that surround the brain and spinal cord.Objective: This is a retrospective analysis of the recorded data of patients managed for intracranial meningiomas between January 2007 and June 2015 at Apollo Hospital, Dhaka.Methodology: Demographic data was analyzed for all but only patients who had surgery and histological diagnosis were analyzed for outcome.Results: This study shows that meningiomas had female preponderance. Majority cases were above 50 years of age. Convexity is the most common anatomical location of meningioma. Most common symptoms were headache (70%) followed by seizure in 34.3% of patients. 90% of the cases were benign. Malignant meningioma was 1.4% and recurrence was found in 1.4% of cases. Six patients with histological grades I, II and III meningi- omas were sent for stereotactic radiotherapy after incomplete tumor resection or for residual tumour. Total removal was done in 80% cases and the mortality was 1.4%, in patient who had poor GCS score on admission.Pulse Vol.9 January-December 2016 p.22-26

A case report of congenital high airway obstruction syndrome (CHAOS) caused by complete laryngeal obstruction

CHAOS or Congenital High Airway Obstruction Syndrome is a blockage of the fetus’s trachea or larynx due to a number of factors including narrowing of the airway, a web-like membrane or even tracheal atresia. In the uterus, the fetal lungs constantly produce fluid and as a result of this airway blockage in the trachea, the lung fluid cannot escape out of the fetal mouth. Because of this the fetus’s lungs become distended with fluid and over distended lungs can put pressure on the heart and affect the heart’s ability to function. If the heart cannot beat effectively hydrops or congestive heart failure can occur. We present a case of CHAOS with hydrops and associated anomalies, determined prenatally at about 21 weeks by MRI in our hospital.Pulse Vol.7 January-December 2014 p.38-41

A case report of spinal intramedullary lipoma

3 months old boy presented with inablility to move upper limb and cries on touching the upper limb from 1 week of age. On examination reflexes were absent in upper limb but hyper reflexia was found in lower limb. Cervical and brain MRI revealed expansion of the cervical spinal canal with smoothly marginated mass within the cervical cord which is hyperintense in T1WI, T2WI and completely loses its signal intensity in FS and gradient weighted sequences. There was no diffusion restriction and appears mostly intramedullary. MRI features were consistent with intramedullary lipoma in cervical spinal cord.Pulse Vol.7 January-December 2014 p.50-52

A case of mr imaging detection of hemorrhages in cerebral amyloid angiopathy

A 70-year-old diabetic and hypertensive male patient with mild renal impairment presented with recurrent stroke. CT scan of brain demonstrated acute hemorrhagic / nonhemorrhagic infarcts in the brain. Gradient sequences in the follow-up MRI showed extensive blooming in the cortex of both cerebral hemispheres. There were multiple foci of blooming in basal ganglia and cerebellar hemispheres. Hemosiderin staining was present in posterior fossa. MR findings were consistent with extensive primary cerebral amyloid angiopathy (CAA).Pulse Vol.7 January-December 2014 p.53-55

Safety and efficacy of multipolar pulmonary vein ablation catheter vs. irrigated radiofrequency ablation for paroxysmal atrial fibrillation: a randomized multicentre trial

Aims

The current challenge in atrial fibrillation (AF) treatment is to develop effective, efficient, and safe ablation strategies. This randomized controlled trial assesses the medium-term efficacy of duty-cycled radiofrequency ablation via the circular pulmonary vein ablation catheter (PVAC) vs. conventional electro-anatomically guided wide-area circumferential ablation (WACA).

Methods and results

One hundred and eighty-eight patients (mean age 62 ± 12 years, 116 M : 72 F) with paroxysmal AF were prospectively randomized to PVAC or WACA strategies and sequentially followed for 12 months. The primary endpoint was freedom from symptomatic or documented >30 s AF off medications for 7 days at 12 months post-procedure. One hundred and eighty-three patients completed 12 m follow-up. Ninety-four patients underwent PVAC PV isolation with 372 of 376 pulmonary veins (PVs) successfully isolated and all PVs isolated in 92 WACA patients. Three WACA and no PVAC patients developed tamponade. Fifty-six percent of WACA and 60% of PVAC patients were free of AF at 12 months post-procedure (P = ns) with a significant attrition rate from 77 to 78%, respectively, at 6 months. The mean procedure (140 ± 43 vs. 167 ± 42 min, P<0.0001), fluoroscopy (35 ± 16 vs. 42 ± 20 min, P<0.05) times were significantly shorter for PVAC than for WACA. Two patients developed strokes within 72 h of the procedure in the PVAC group, one possibly related directly to PVAC ablation in a high-risk patient and none in the WACA group (P = ns). Two of the 47 patients in the PVAC group who underwent repeat ablation had sub-clinical mild PV stenoses of 25–50% and 1 WACA patient developed delayed severe PV stenosis requiring venoplasty.

Conclusion

The pulmonary vein ablation catheter is equivalent in efficacy to WACA with reduced procedural and fluoroscopy times. However, there is a risk of thrombo-embolic and pulmonary stenosis complications which needs to be addressed and prospectively monitored.

ClinicalTrials.gov Identifier

NCT00678340.

Neural network modelling of asphalt adhesion determined by AFM

This study constructs a neural network (NN) model to quantify adhesion from atomic force microscopy (AFM) data. AFM data contain five-point force-distance values. A total of 760 observations are used to build NN model. To train the network, AFM tip-sample distance data, percentage of lime, type and percentage of polymer and asphalt chemical functional groups are given as inputs and AFM force as an output. To select the NN architecture, one and two hidden layers with varying neurons are tried with 10 input nodes in the input layer and 5 output nodes in the output layer. Two hidden layers with 9 and 17 nodes in the first and second layer, respectively, show the best performance. A 10-9-17-5 NN is selected as the final structure of the NN model. Test results for the trained model show good prediction ability. The model is further applied to evaluate the effect of five different percentages of lime on the adhesion of asphalt. Results show that increase in the percentage of lime is very effective at reducing moisture damage in a styrene butadiene polymer modified asphalt sample. However, increase in lime percentage above 1.5% does not help reduce moisture damage in the styrene butadiene styrene polymer modified sample.

Predictors and prevalence of germ-line BRCA mutations in high-risk patients among different ethnicities

190

Background: Germ-line mutations in tumor suppressor genes, BRCA1 and BRCA2, confer high risks of breast and ovarian cancer in affected individuals. Genetic testing for these pathogenic mutations has potentially important health implications for judicious counseling and screening of high risk individuals.

Methods: A retrospective analysis was conducted of all the patients seen at our oncology/genetics clinic from 2000 to 2010. A population of over 500 patients was identified, out of whom 310 subjects underwent risk factor assessment. BRCA testing was performed on 231 of these subjects whereas 79 subjects were not tested secondary to lack of insurance/follow up, or patient/physician preference. Various ethnic groups were identified which included 138 Caucasian, 41 African American, 28 Ashkenazi Jewish, 4 Middle Eastern, 2 Asian and 2 Hispanic subjects. The ethnicity of 16 subjects was unknown secondary to lack of documentation.

Results: BRCA mutation testing was completed on 231 subjects out of whom 34 were identified as carriers, comprising 31 female and 3 male individuals. 25 subjects carried BRCA1 and 11 subjects carried BRCA2 mutations, whereas 2 subjects carried both mutations simultaneously. In terms of racial prevalence, the population screened was divided into 4 main groups. Using the Maximum Likelihood Ratio Chi-Square Test, a p-value of 0.96 (p=0.9633) was obtained which indicated that the proportion of mutation did not differ for the races among the population screened.

Conclusions: The estimated ethnicity prevalence of BRCA mutations was found to be the highest in African American followed by Caucasian and Ashkenazi Jewish subjects in the population screened at our facility. Overall, BRCA mutations are more common in the Jewish population on which most of the research has been focused. Our study is one of the few to indicate the possibility of high prevalence of mutations in the under-studied and less reported high risk kindred, that is, the African Americans.

[Table: see text]

Early administration of thrombolysis can prevent myocardial necrosis: time is myocardium

A case is presented in which a 66-year-old man received thrombolysis for an acute ST elevation myocardial infarction (STEMI) within 6 minutes of developing chest pain. An ECG performed 10 minutes after thrombolysis showed complete resolution of the ST segment elevation and showed no other abnormality. An echocardiogram showed normal left ventricular function and there was no detectable myocardial necrosis, as evidenced by two negative troponin assays. The case clearly reinforces the benefits of the rapid delivery of thrombolysis when appropriate for patients with STEMI. Clinicians need to be aware of the benefits of early thrombolysis as laid out in the national service framework. Evidence for the early administration of thrombolysis, data from the Myocardial Infarction National Audit Project and the future with regard to improving thrombolysis times are discussed.

Current developmental surveillance: is it time for change?

Developmental screening tools are an integral part of child health surveillance, but only few valid and reliable tests are currently in use in the community. Early detection and referral of children with developmental delay is critical for long term outcomes. Developmental screening, using standardised tests, is increasingly important. The public health nurses in the Midlands currently use a modified version of Denver Development Screening Tool (DDST) for screening infants at 9 months of age. The DDST however fails to identify a high proportion of children developmentally at risk, because of its poor sensitivity, an outcome of which is a high proportion of under-referrals. The low sensitivity of the test is a source of potentially misleading information and may be responsible for many at-risk children remaining undetected. Sensitive and specific screening questionnaires need to be introduced in community child health screening surveillance to minimise the risk of missing children with developmental delay.

Preoperative discrimination of benign and malignant ovarian tumors using color Doppler sonography and its correlation with histopathology

A total of forty clinically diagnosed ovarian tumors were studied over a period of one year. The study aimed at evaluating the efficacy of trans-vaginal color Doppler sonography (TV-CDS) in preoperative discrimination of benign and malignant ovarian tumors and to correlate the imaging findings with postoperative histopathological findings. The pulsatility Index (PI) and Resistive Index (RI) were studied as primary effecacy variables of TV-CDS. In the present study, using TV-CDS, 72.5% of the ovarian tumors were found benign and 22.8% were malignant which were significantly correlated with postoperative histopathological findings. The average PI for benign and malignant tumors were 1.98 and 0.77 respectively and RI for benign and malignant tumors were 0.62 and 0.41 respectively. The low PI and RI values in malignant tumors as compared to benign ones were statistically highly significant (p < 0.001). The validity tests for TV-CDS were found to be 90% sensitive, 100% specific and 97% accurate. The study concludes that TV-CDS is a useful imaging diagnostic modality in preoperative discrimination of benign and malignant ovarian tumors due to its excellent characterization of tumors neo-vascularization.

Bilateral giant angiomyolipoma of kidneys: a case report and review of literature

Angiomyolipoma is uncommon benign tumor of the kidney. Bilateral and multiple lesions are associated with tuberous sclerosis. We report a case with bilateral giant angiomyolipomas in a patient who had no other features of tuberous sclerosis. In this case, the involvement of the kidneys was diffuse rather than usual well-circumscribed lesions.

Caspases, the Enemy Within, and Their Role in Oxidative Stress-Induced Apoptosis of Inner Ear Sensory Cells

This review covers the general roles of members of the cysteine protease family of caspases in the process of apoptosis (programmed cell death) looking at their participation in both the "extrinsic" cell death receptor and the "intrinsic" mitochondrial cell death pathways. It defines the difference between initiator and effector caspases and shows the progression of caspase activations that ends up in the apoptotic cell death and elimination of a damaged cell. The review then presents what is currently know about the participation of caspases in the programmed cell death of inner ear sensory cells during the process of normal development and maturation of the inner ear and their importance in this process as illustrated by the results of caspase-3 gene knockout experiments. The participation of specific caspases and the sequence of their activation in the elimination (apoptosis) of damaged sensory cells from adult inner ears after an injury that generates oxidative stress are reviewed. Both the possibility and the potential efficacy of caspase inhibition with a broad-spectrum pancaspase inhibitor as an interventional therapy to treat and rescue oxidative stress-damaged inner ear sensory cells from apoptosis are presented and discussed.

A case notes analysis of hysterectomy performed for non-neoplastic indications at Liaquat National Hospital, Karachi

OBJECTIVE

To determine the indications, associated morbidity, mortality and histopathological findings in women who underwent hysterectomy for non-neoplastic indications at Liaquat National Hospital Karachi.

MATERIAL AND METHODS

This is a five year retrospective case note study of 143 women who underwent hysterectomy, excluding all those performed for benign or malignant pelvic neoplasms (excluding fibroids) and hysterectomy following childbirth for postpartum haemorrhage.

RESULTS

Menorrhagia was the commonest indication for performing hysterectomy. The majority of the patients were in their forties; the commonest post operative complications were pyrexia, urinary tract and wound infections in 16% of the patients. There was no mortality associated with the procedure. The histopathology of the specimens revealed adenomyosis followed by leiomyoma to be the commonest pathology.

CONCLUSION

It appears that adenomyosis is a common pathology in women from various ethnic and social backgrounds in Karachi, who are suffering from menorrhagia. Early diagnosis with high-resolution ultrasound is possible and hysterectomy may be offered earlier to these women, as they do not usually respond to medical treatment.

Use of some natural and waste materials for waste water treatment

A fundamental study was conducted to assess removal and filtration capacity of waste and natural indigenous materials as treatment mediums e.g., shell, limestone, waste paper mixed with refuse concrete, refuse cement, also processed nitrolite, charcoal-bio and charcoal. Under room temperature condition removal of phosphoric, nitric and ammonium-ions, filtration of suspended substance (SS) together with removal of COD in waste water was investigated. Influence of particle size effect for all treatment mediums except for waste paper was pursued. Significant improvement of waste water quality with respect to SS, phosphoric ions and decrease in COD is possible by treating with these filtration mediums. With specific reference to some treatment mediums NO3-N and NH4-N showed reasonable improvement in quality, although generally removal effect was not very significant. Efficacy of treatment was dependent on the particle size of treatment mediums in general, however, nitrolite for NH4--N, charcoal-A for SS and COD, refuse cement mixed with waste paper for PO4 ion removal showed insignificant variability on the particle size effect. Results of this fundamental study demonstrate effectiveness and feasibility for applied application of these proposed waste and naturally available treatment ingredients at lower cost.