Is there a role for fibreoptic bronchoscopy in patients presenting with haemoptysis and negative CT? A systematic review and meta-analysis

INTRODUCTION

Haemoptysis can be a feature of lung cancer and patients are typically fast-tracked for evaluation with chest radiography, contrast-enhanced CT and fibreoptic bronchoscopy (FOB).

OBJECTIVE

We aim to explore whether FOB should be conducted as a component of the routine evaluation of non-massive haemoptysis, especially in the context of suspected lung cancer.

METHODS

MEDLINE, EMBASE and Cochrane Library were searched for studies comparing FOB with CT in the evaluation of non-massive haemoptysis while reporting at least one of the listed primary outcomes. Primary outcomes include sensitivity of diagnostic modality with respect to lung cancer. Secondary outcomes include detection of other aetiologies such as infection. Results were synthesised using a random effects meta-analysis. Sensitivity analysis was performed for patient age group and year of study. Risk of bias assessment was carried out with the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

RESULTS

A total of 2273 citations were screened and 11 studies were included, comprising a total sample size of 2015 patients with 226 confirmed cases of lung cancer. A total of 1816 and 1734 patients received a CT scan and FOB, respectively. The pooled sensitivities for detection of lung cancer using CT scan and bronchoscopy were 98% (95% CI 93.0% to 99.0%) and 86% (95% CI 63.0% to 95.0%), respectively. The sensitivity of CT was higher than that of FOB for both primary and secondary outcomes.

CONCLUSION

This study suggests that bronchoscopy does not offer significant additional diagnostic benefit in the evaluation of patients presenting with non-massive haemoptysis and a negative CT scan.

Recurrent cerebellar ischemic infarctions and stereotyped peri-ictal sympathetic responses in a near-SUDEP patient with cardiovascular risk factors

We report a 60-year-old woman who presented to the emergency department after experiencing a witnessed unknown onset bilateral tonic clonic seizure (GTCS) that culminated in cardiac arrest. A neurology consultant uncovered a years-long history of frequent episodic staring followed by confusion and expressive aphasia, which strongly suggested that she suffered from epilepsy. Thus, her cardiac arrest and subsequent resuscitation met criteria for a near-sudden unexpected death in epilepsy (SUDEP) diagnosis. Serial bloodwork demonstrated transient troponin I elevations and leukocytoses, while a brain MRI revealed global cerebral anoxic injury and a small acute right cerebellar ischemic infarction. A review of her medical record uncovered a hospitalization sixteen months earlier for a likely GTCS whose workup showed similar troponin I elevations and leukocytoses, and surprisingly, a different small acute right cerebellar ischemic infarction in the same vascular territory. To our knowledge, this is the first report of subcortical ischemic infarctions occurring concurrently with GTCSs in a near-SUDEP patient. Aside from illustrating the key role of inpatient neurologists in the diagnosis of near-SUDEP, this manuscript discusses the potential significance of postictal ischemic infarctions, transient asymptomatic troponin elevations, and transient non-infectious leukocytoses in epilepsy patients with cardiovascular risk factors.

Outcomes of Continuous Positive Airway Pressure in the Management of Patients with Coronavirus (COVID-19) Pneumonia who are not Suitable for Invasive Ventilation

BACKGROUND

The optimum management of respiratory failure in patients with coronavirus (COVID-19) infections has been a challenge for physicians across the globe. Many scientific societies have suggested the use of CPAP (continuous positive airway pressure) in severe cases in an effort to reduce invasive ventilation. We investigated mortality outcomes in patients who needed CPAP but were not suitable for invasive ventilation.

METHODS

We retrospectively evaluated the mortality outcomes of all consecutive COVID-19 cases with severe type 1 respiratory failure requiring FiO2 >0.6 who were admitted to our hospital between 12th March and 04th May'20. British Thoracic Society guidelines were followed for identifying patients needing CPAP. Their outcomes were recorded and compared with a similar group of patients who had oxygen as a ceiling of care. Prospectively collected data between 5th May and 7th June'20 in similar but smaller groups of patients was also analyzed.

RESULTS

A total of 104 COVID-19 patients with documented Do Not Attempt Resuscitation (DNAR) decision required high fraction of inspired oxygen (FiO2) >0.6(to maintain peripheral oxygen saturation (SpO2)> 92%(SpO2> 88% in COPD patients). Twenty-four patients received CPAP as the ceiling of care, with a mortality rate of 92.5%. The remaining 84 patients who were on oxygen as a ceiling of treatment had 91.7% mortality. Both population groups had a similar number of comorbidities but were less favorable in terms of age in the control group with standard O2 therapy than those who had CPAP support. Overall mortality outcomes from using CPAP therapy did not bring significant mortality benefit (p-value-0.89).

CONCLUSION

CPAP did not appear to improve the survival of patients with severe respiratory failure due to COVID-19 related pneumonia and were not suitable for invasive ventilation. Further studies are warranted to adequately inform appropriate management strategies for this group of patients.

Safety and acute clinical outcomes of atrial fibrillation catheter ablation in octogenarians: a multicentre evaluation with a matched younger cohort

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

Sven Knecht and the International Octogenarian AF ablation group

Background

Octogenarians are a fast-growing demographic with a high burden of atrial fibrillation (AF). There are limited data on procedural safety and acute outcomes of catheter ablation (CA) for AF in this group.

Purpose

Investigation of complications & outcomes in octogenarians undergoing CA for AF.

Methods

Data on all octogenarian patients who underwent AF ablation at nine European cardiology centres between 2013 and 2019 were retrospectively analysed and matched with control patients aged <80 years.  The characteristics used for matching were type of AF, type of procedure (de novo or redo), & the year of procedure.

Results

216 octogenarians (81.9 ± 1.9 years; 52.8% females) underwent an AF ablation procedure, and were matched with 216 patients aged <80 years (62.4 ± 9.5 years, 34.7% females), p <0.001 for both. The proportion of paroxysmal and persistent AF was 43.5% & 56.5% respectively in both groups, and 79.3% of the procedures were de novo. RF ablation made up 75.4% & 75.9% (p = 0.90) procedures in octogenarians and controls respectively.  17 complications occurred in 14 (7.9%) octogenarian patients and 11 in 11 (5.1%) patients in the younger matched cohort (p = 0.07). There were 4.2% & 1.9% major complications (p= 0.17) and 3.7% & 3.2% minor complications (p= 0.77) in the octogenarian & younger cohorts respectively. Complications in octogenarians consisted of groin complications (n = 6), pneumonia (n = 3), pericardial effusion (n = 2), phrenic nerve injury (n = 2), pulmonary oedema (n = 1), gastroparesis (n = 1), stroke (n = 1). Acute procedural success rates were 99.1% & 99.5% (p = 0.62) The complication rates were similar for RF; 6.0% vs 5.4% (p = 0.79) and Cryoballoon; 14.0% vs 4.1% (p = 0.09) in both octogenarians and younger cohort respectively.

Conclusion

In spite of significantly higher overall risk profile of octogenarians undergoing AF ablation, there is no difference in acute procedural success and complication rates as compared to younger patients Catheter ablation of AF in octogenerians Octogenarians n = 216 Matched Controls (aged < 80yrs) n = 216 P value Age (yrs), mean (SD)s 81.9 (1.9) 62.4(9.5) < 0.0001 Females, (%) 52.8 34.7 0.0002 CHA2DS2-VASc, mean (SD) 3.6 (1.2) 1.4 (1.3) < 0.0001 Mean LA size, mm 42.8 ± 8.3mm 45.8 ± 16.2 0.062 Impaired LV function, (%) 23.7 17.9 0.206 IHD, (%) 20.7 5.9 < 0.0001 Procedural time (mins), mean (sd) 150.6 (69.7) 148.9 (64.4) 0.914 All complications, n (%) 17 (7.9) 11 (5.1) 0.073

Utility of the FebriDx point-of-care test for rapid triage and identification of possible coronavirus disease 2019 (COVID-19)

OBJECTIVES

The Coronavirus disease 2019 (COVID-19) pandemic is straining healthcare resources. Molecular testing turnaround time precludes having results at the point-of-care (POC) thereby exposing COVID-19/Non-COVID-19 patients while awaiting diagnosis. We evaluated the utility of a triage strategy including FebriDx, a 10-minute POC finger-stick blood test that differentiates viral from bacterial acute respiratory infection through detection of Myxovirus-resistance protein A (MxA) and C-reactive protein (CRP), to rapidly isolate viral cases requiring confirmatory testing.

METHODS

This observational, prospective, single-center study enrolled patients presenting to/within an acute care hospital in England with suspected COVID-19 between March and April 2020. Immunocompetent patients ≥16 years requiring hospitalisation with pneumonia or acute respiratory distress syndrome or influenza-like illness (fever and ≥1 respiratory symptom within 7 days of enrolment, or inpatients with new respiratory symptoms, fever of unknown cause or pre-existing respiratory condition worsening). The primary endpoint was diagnostic performance of FebriDx to identify COVID-19 as a viral infection; secondary endpoint was SARS-CoV-2 molecular test diagnostic performance compared with the reference standard COVID-19 Case Definition (molecular or antibody detection of SARS-CoV-2).

RESULTS

Valid results were available for 47 patients. By reference standard, 35 had viral infections (34/35 COVID-19; 1/35 non-COVID-19; overall FebriDx viral sensitivity 97.1% (95%CI 83.3-99.9)). Of the COVID-19 cases, 34/34 were FebriDx viral positive (sensitivity 100%; 95%CI 87.4-100); 29/34 had an initial SARS-CoV-2 positive molecular test (sensitivity 85.3%; 95%CI 68.2-94.5). FebriDx was viral negative when the diagnosis was not COVID-19 and SARS-Cov-2 molecular test was negative (negative predictive value (NPV) 100% (13/13; 95%CI 71.7-100)) exceeding initial SARS-CoV-2 molecular test NPV 72.2% (13/19; 95%CI 46.4-89.3). The diagnostic specificity of FebriDx and initial SARS-CoV-2 molecular test was 100% (13/13; 95%CI 70-100 and 13/13; 95%CI 85.4-100, respectively).

CONCLUSIONS

FebriDx could be deployed as part of a reliable triage strategy for identifying symptomatic cases as possible COVID-19 in the pandemic.

P2831Safety of atrial fibrillation catheter ablation in the elderly

Background

Catheter ablation for drug refractory, symptomatic atrial fibrillation (AF), is becoming increasingly common and can be beneficial in alleviating symptoms. However, in the elderly, there are concerns about the risks an invasive procedure poses, with limited published data available in those aged over 80 years.

Purpose

To determine the complication risk of AF catheter ablation in the elderly

Methods

Complications were identified from patient records in 3156 consecutive patients who underwent radiofrequency catheter ablation for AF, at a tertiary cardiology centre between 2013–2017. All cases were performed under general anesthesia.

Results

In this cohort of 3156 patients (mean age= 62.9±11.0 years, female = 29.9%), 90 (2.85%) (mean age= 66±10.0 years, female = 49.5%) complications were identified. In patients aged ≥80 years, complications occurred in 5 out of 99 patients (5.05%) (mean age= 82.6±1.2, female=100%), compared to 85 out of 3057 patients (2.78%) in those aged <80 years (mean age= 65±10.3, female = 49.4%). The difference was not significant p=0.18. Complications in the elderly all occurred acutely, and included groin haematoma (2.02%), pneumonia (2.02%) and pericardial effusion (1.01%).

Conclusion

Catheter ablation for AF in patients ≥80 years of age, is not associated with a significant increase in complication risk, compared to those who are younger.

JAK-STAT and G-protein-coupled receptor signaling pathways are frequently altered in epitheliotropic intestinal T-cell lymphoma

Epitheliotropic intestinal T-cell lymphoma (EITL, also known as type II enteropathy-associated T-cell lymphoma) is an aggressive intestinal disease with poor prognosis and its molecular alterations have not been comprehensively characterized. We aimed to identify actionable easy-to-screen alterations that would allow better diagnostics and/or treatment of this deadly disease. By performing whole-exome sequencing of four EITL tumor-normal pairs, followed by amplicon deep sequencing of 42 tumor samples, frequent alterations of the JAK-STAT and G-protein-coupled receptor (GPCR) signaling pathways were discovered in a large portion of samples. Specifically, STAT5B was mutated in a remarkable 63% of cases, JAK3 in 35% and GNAI2 in 24%, with the majority occurring at known activating hotspots in key functional domains. Moreover, STAT5B locus carried copy-neutral loss of heterozygosity resulting in the duplication of the mutant copy, suggesting the importance of mutant STAT5B dosage for the development of EITL. Dysregulation of the JAK-STAT and GPCR pathways was also supported by gene expression profiling and further verified in patient tumor samples. In vitro overexpression of GNAI2 mutants led to the upregulation of pERK1/2, a member of MEK-ERK pathway. Notably, inhibitors of both JAK-STAT and MEK-ERK pathways effectively reduced viability of patient-derived primary EITL cells, indicating potential therapeutic strategies for this neoplasm with no effective treatment currently available.

A model of chlorpyrifos distribution and its biochemical effects on the liver and kidneys of rats

This study investigated the main target sites of chlorpyrifos (CPF), its effect on biochemical indices, and the pathological changes observed in rat liver and kidney function using gas chromatography/mass spectrometry. Adult female Wistar rats (n = 12) were randomly assigned into two groups (one control and one test group; n = 6 each). The test group received CPF via oral gavage for 21 days at 5 mg/kg daily. The distribution of CPF was determined in various organs (liver, brain, heart, lung, kidney, ovary, adipose tissue, and skeletal muscle), urine and stool samples using GCMS. Approximately 6.18% of CPF was distributed in the body tissues, and the highest CPF concentration (3.80%) was found in adipose tissue. CPF also accumulated in the liver (0.29%), brain (0.22%), kidney (0.10%), and ovary (0.03%). Approximately 83.60% of CPF was detected in the urine. CPF exposure resulted in a significant increase in plasma transaminases, alkaline phosphatase, and total bilirubin levels, a significant reduction in total protein levels and an altered lipid profile. Oxidative stress due to CPF administration was also evidenced by a significant increase in liver malondialdehyde levels. The detrimental effects of CPF on kidney function consisted of a significant increase in plasma urea and creatinine levels. Liver and kidney histology confirmed the observed biochemical changes. In conclusion, CPF bioaccumulates over time and exerts toxic effects on animals.

Hypothalamic pituitary dysfunction amongst nasopharyngeal cancer survivors

PURPOSE

Radiation fields for nasopharyngeal cancer (NPC) include the base of skull, which places the hypothalamus and pituitary at risk of damage. We aimed to establish the prevalence, pattern and severity of hypothalamic pituitary (HP) dysfunction amongst NPC survivors.

METHODS

We studied 50 patients (31 males) with mean age 57 ± 12.2 years who had treatment for NPC between 3 and 21 years (median 8 years) without pre-existing HP disorder from other causes. All patients had a baseline cortisol, fT4, TSH, LH, FSH, oestradiol/testosterone, prolactin and renal function. All patients underwent dynamic testing with insulin tolerance test to assess the somatotroph and corticotroph axes. Baseline blood measurements were used to assess thyrotroph, gonadotroph and lactotroph function.

RESULTS

Hypopituitarism was present in 82% of patients, 30% single axis, 28% two axes, 18% three axes and 6% four axes deficiencies. Somatotroph deficiency was most common (78%) while corticotroph, gonadotroph and thyrotroph deficiencies were noted in 40% (4 complete/16 partial), 22 and 4% of the patients respectively. Hyperprolactinaemia was present in 30% of patients. The development of HP dysfunction was significantly associated with the time elapsed from irradiation, OR 2.5 (1.2, 5.3), p = 0.02, for every 2 years post treatment. The use of concurrent chemo-irradiation (CCRT) compared to those who had radiotherapy alone was also significantly associated with HP dysfunction, OR 14.5 (2.4, 87.7), p < 0.01.

CONCLUSION

Despite low awareness and detection rates, HP dysfunction post-NPC irradiation is common. Use of CCRT may augment time related pituitary damage. As these endocrinopathies result in significant morbidity and mortality we recommend periodic assessment of pituitary function amongst NPC survivors.

When nonspecific histology can be a clue to the diagnosis: three cases of trigeminal trophic syndrome

Trigeminal trophic syndrome (TTS) is a rare cause of facial ulceration, which is usually associated with damage to the trigeminal nerve pathway, either centrally or peripherally, the most common causes being cerebrovascular accidents and trigeminal nerve ablation procedures. We present three cases of TTS, emphasizing the histopathological features. All three patients presented with facial ulceration. Two patients had a single lesion, and the third had several ulcers. However, in all cases, there was involvement of the nasal ala, and the lesions were strictly unilateral. Histology consistently showed ulceration with signs of severe chronic trauma: scarring, lichenification and/or pseudoepitheliomatous hyperplasia. Diagnosis of TTS can be difficult, and requires close clinicopathological correlation. Histology is important in excluding the majority of possible conditions included in the differential diagnosis, mainly malignancy and infectious processes. Several treatments have been described, but TTS is frequently refractory to treatment.

Risk factors of acute coronary syndrome among Bangladeshi people

Two hundred consecutive patients of acute coronary syndrome aged 30-80 years (inclusive) admitted to the coronary care unit of National institute of Cardiovascular Diseases, Dhaka, were prospectively recruited as cases. Two hundred controls were prospectively selected either from individuals attending in the Shaheed Suhrawardy Medical College Hospital, admitted for elective surgery or in medicine ward for conditions that were unlikely to confound a comparative analysis. The Cases had significantly lower yearly incomes than controls, and significantly higher number of cases is occupied as sedentary worker. Smoking was an important risk factor. About 70% of cases and 45% of controls smoked previously cigarettes. Consumption of non smoke tobacco is another risk factor. The high risk of IHD in developing countries attributed to low consumption of fruit and vegetables, and in our study regular consumption of fruits (taking fruit at least 4 days a week) shows 20.5% cases and 33% of controls (OR 0.524, 95%CI 0.333-0.823) and p value was 0.005. Around 23.5% of the cases were diabetic compared with 4.5% of controls. We found 5% cases and 1.5% controls having known dyslipidemia. Although the body-mass index of cases was 24.68±3.06 Kg/M² and controls 20.54±4.37 Kg/M². The WHR was also significantly greater in cases 0.98±0.05M vs. controls 0.93±0.102M (p<0.001). About 31% of cases and 2% of controls had past history of myocardial infarction. The most predictive independent variables were previous smoking (p<0.001), WHR (p<0.001), history of hypertension (p<0.001), and income (p<0.001). Smoking and WHR were associated with the highest risks. The variables revealed to be significantly associated with acute coronary syndrome by bivariate analyses were all entered into the model directly. Eleven variables entered into the model. Of them Age, occupation, family income (yearly), fruit consumption, known hypertension, known DM, known dyslipidemia, previous MI, previous smoking, BMI and Waist and hip ratio were found to be the independent predictors of acute coronary syndrome. The study found that smoking tobacco, diabetes mellitus, hypertension, visceral obesity and less fruit intake are the important factors of acute coronary syndrome in Bangladesh.

Endodontic release system for apexification with calcium hydroxide microspheres

The use of calcium hydroxide (CH) as an intracanal medicament for apexification is widespread. However, because of a short residence time in the root canal, the CH must be refreshed frequently, increasing the number of appointments required and leading to patient non-compliance. We hypothesized that a core-/shell-structured CH microsphere system would lead to sustained slow release of calcium and hydroxide ions of CH for long periods of time, eliminating the need for multiple visits for apexification. In this study, calcium hydroxide microspheres (CHMSs) with a core/shell structure were prepared by an emulsion method. The CHMS shell was composed of alginate, which was crosslinked by the Ca(2+) released from the CH in the CHMSs. Therefore, this system provides a unique feedback loop that controls the release of ions from the CHMSs. The in vitro experiments from the root canals of extracted human teeth showed that the CHMSs had a sustained, slow release of Ca(2+), at a constant rate of approximately 2 to 3% per month from day one to the six-month endpoint of the experiment. After 6 months, 72.1 ± 5.8% of the total CH from the CHMSs remained in the root canals of the teeth, while only 46.9 ± 10.9% and 36.8 ± 7.5% remained from a commercial product (UltraCal(®)XS) and CH powder alone, respectively (p < 0.01). The pH of all of the formulations (CHMS, UltraCal(®) XS, and CH powder) in the extracted teeth never rose above 9 during the release period, indicating a buffering effect of the teeth. The core-/shell-structured CHMSs are, therefore, a promising delivery vehicle for the sustained slow release of Ca(2+) and OH(-) in the root canal.

Follicular thyroid carcinoma with insular component: a retrospective case study, immunohistochemical analysis and literature review

This is a retrospective case study of a 61-year-old woman diagnosed with follicular thyroid carcinoma. The patient underwent thyroidectomy for the treatment of goitre after being admitted for shortness of breath. Microscopic and immunohistochemical studies were performed, which confirmed follicular carcinoma of the thyroid with an insular component. We also conducted a review of the literature on this uncommon entity.

Differential expression of galectin-3 in advancing thyroid cancer cells: a clue toward understanding tumour progression and metastasis

INTRODUCTION

Galectin-3 is a member of the beta-galactoside-binding protein family that plays an important role in cell-to-cell adhesion and in cell-to-matrix interaction. Cellular expression of galectin-3 is correlated with cancer aggressiveness and metastasis.

METHODS

We examined the differential expression of galectin-3 in a collection of 142 cases of thyroid lesions, including 108 cases of papillary thyroid carcinoma (PTC) and 34 cases of follicular carcinoma (FCA). An immunohistochemical method was applied and semiquantitative scoring was performed on the staining intensity of the positive tissue. Scoring was done on cells at the central portion of the tumour foci and on cells at the periphery that were adjacent to the neighbouring normal thyroid tissue matrix.

RESULTS

A significantly higher expression (p is 0.001) of galectin-3 was observed in the advancing peripheral thyroid cancer cells compared to the centrally located cells that were not in close contact with the neighbouring stromal tissue in cases with PTC compared to those with FCA.

CONCLUSION

This finding supported the role of galectin-3 in its cell-to-cell adhesion and cell-to-matrix interaction. Galectin-3 is a potential tumour marker for indicating local and distance metastasis, especially in cases with PTC.

The relationship between gonadotrophins, gonadal hormones and bone mass in men

OBJECTIVE

Inhibin A and B (Inh A and B), activin A (Act A) as well as FSH may play an important role in bone turnover in perimenopausal women. Data in men are lacking. The aim was to investigate the relationship between circulating concentrations of Inh B and Act A and FSH/LH/testosterone (T) and their contribution to bone mineral density (BMD) in a male population.

DESIGN AND SUBJECTS

Cross-sectional case-control study of 156 men, 63 with osteoporosis and 93 controls, aged (mean [SD]) 57.7 [13.7] years.

MEASUREMENTS

Areal (aBMD) was measured at the femoral neck, total hip and lumbar spine. Volumetric BMD (vBMD) was calculated at the femoral neck and lumbar spine. Risk factors were assessed including the measurement of LH/FSH/T, Inh B and Act A.

RESULTS

After correction for age and body mass index (BMI), associations were found between Inh B and FSH (beta regression coefficient beta = -0.326; P < 0.0001), T (beta = -0.36; P = 0.019) and Act A (beta = -0.4; P = 0.007) and between Inh B and LH (beta = 0.23; P < 0.0001) in all patients. The controls had higher Inh B concentrations compared to the cases (Inh B: controls: 139 [86] pg/ml vs. cases 88 [51] pg/ml; P = 0.005). Act A tended to be lower in the controls (Act A: controls 0.63 [0.24] ng/ml vs. cases 0.75 [0.4] ng/ml; P = 0.056). Univariate regression analyses showed a positive association between Inh B and BMD (P < 0.01) at the lumbar spine and total hip. In contrast a negative association was seen between FSH and BMD at the lumbar spine and femoral neck (P < 0.01). In a partial multivariate regression model that included the gonadal factors only, a positive association was seen between Inh B and BMD at the hip (beta = 0.088; P = 0.04). When all hormones including the gonadotrophins were entered in a full multivariate model, FSH and LH were found to be better predictors of BMD than Inh B or Act A in the controls and cases.

CONCLUSIONS

These data suggest that the gonadal peptides and gonadotrophins may play a role in the maintenance of bone mass in men. Future confirmatory longitudinal studies are needed.

This is not déjà vu all over again: male guppy colour in a new experimental introduction

We use an experimental introduction in nature to examine factors that influence parallel evolution. In 1996, 200 high-predation guppies (Poecilia reticulata) from the Yarra River were introduced into the Damier River, which previously lacked guppies. Eight years later, we quantified the colour of wild-caught guppies ('phenotypic' divergence) and lab-reared guppies ('genetic' divergence) from low- and high-predation environments in both rivers. Phenotypic and genetic divergence between predation environments within the Yarra was evident for black and for orange. Phenotypic divergence within the Damier was parallel to the Yarra for black but not for orange. Genetic divergence was absent between predation environments within the Damier, but was evident when comparing both Damier populations to their Yarra ancestors. The evolution of male colour thus depends on factors other than the simple contrast between 'high' and 'low' predation. We suggest that the parallel evolution of male signalling traits may sometimes first require the parallel evolution of female preferences.

Loss of human leucocyte antigen class I and gain of class II expression are early events in carcinogenesis: clues from a study of Barrett's oesophagus

BACKGROUND

Human leucocyte antigen (HLA) expression is altered in oesophageal carcinomas compared with normal tissue. It is unclear, however, whether this phenotype precedes malignant transformation or results as a consequence of it.

AIM

To investigate HLA class I and II expression in Barrett's oesophagus and normal squamous oesophageal tissue.

METHODS

Asian patients with Barrett's oesophagus (n = 64) and a control group (n = 60) with a normal oesophagus but without reflux symptoms were recruited using endoscopic and histopathological criteria. Tissue samples were stained with monoclonal antibodies specific for HLA-ABC, HLA-DR alpha chain or HLA-DP/DQ/DR, and scored semiquantitatively. The results of immunohistochemical staining were correlated with clinical and histopathological characteristics of patients.

RESULTS

Marked expression of HLA-ABC was observed in 50% of Barrett's oesophagus sections as compared with 68.3% of controls (p = 0.038). HLA-DR staining was seen in 51.6% of Barrett's oesophagus samples versus 11.7% of controls (p<0.001). Expression of HLA-DP/DQ/DR was evident in 73.4% of oesophageal intestinal metaplasia tissue as opposed to 18.3% of controls (p<0.001). Importantly, a total loss of HLA-ABC and a concomitant gain of HLA-DP/DQ/DR expression were seen in 37.5% of patients with Barrett's oesophagus but in none of the controls (p<0.001). Interestingly, this phenotype was associated positively with dysplasia (adjusted p, p* = 0.031) but negatively with non-steroidal anti-inflammatory drug use (p* = 0.004).

CONCLUSIONS

HLA class I expression is down regulated and class II expression is up regulated in Barrett's oesophagus. As these changes predate malignant transformation, altered major histocompatibility complex expression may be a key event in disease progression, possibly in facilitating evasion from immune surveillance.

The profile of lymphadenopathy in adults and children

Surgical biopsies of lymphnodes of 315 patients (273 adult and 42 children) were reviewed microscopically and analysed. The sex ratio was similar in adults but in children males were twice than female (2:1). Ethnically Malay patients predominated in both the groups. The commonest cause of biopsied lymphadenopathy in adults were malignancy (47%) followed by chronic nonspecific lymphadenitis (20%) and granulomatous lymphadenitis (9%) while in children chronic nonspecific lymphadenitis was the commonest (46%) followed by granulomatous lymphadentitis (21%) and malignancy (14%). Twenty percent of adults and 4% of children had normal lymphnodes. Secondary deposits in adult males and females were of squamous cell carcinoma and adenocarcinoma type respectively. In our study 100% of clildren and 96% of adults with granulomatous lymphadenitis had tubercular lesions.

[Immunophenotyping of acute leukemias: diagnostic and pronostic utility in Abidjan, Côte d'Ivoire]

Flow cytometry is nowadays the first-line method for immunophenotypic identification of blast cells but is not so usual in limited-resources countries. We have investigated on the usefulness of this tool in Abidjan, Côte d'Ivoire. Bone marrow sample from 13 patients with acute leukemia identified by cytology and cytochemical analysis was immunophenotyped by using monoclonal antibodies directed to: T lymphoid cells (CD3, CD5, CD7); B lymphoid cells (CD10, CD19, CD20, CD22, HLA-DR) and myeloid cells (CD13, CD33). Immunophenotyping allowed us to confirm the diagnosis of 6 de novo acute leukemias (2 acute myeloid leukaemias, 4 acute lymphoid leukemias) and 7 acute leukaemias resulting from chronic myeloid leukaemias. Immunophenotyping also characterizes the atypical/aberrant lineage essential for the prognosis: 2 biphenotypic acute leukemias (myeloid/lymphoid T) were identified. Our results suggest that flow cytometry may be a useful additional tool to identify the specific leukemic cell, to make a better classification as well as a prognosis evaluation of patients with acute leukemias.

Ulcerative colitis and motor neurone disease: causal or coincidental?

Neurological involvement associated with inflammatory bowel disease is well established though rarely reported in the literature. The coexistence of motor neurone disease with ulcerative colitis has never been previously documented. The case of a 53-year-old Indian male with distal ulcerative colitis who, two and a half years later, developed dysarthria, dysphagia, a wasted fasciculating tongue and palatal palsy characteristic of bulbar type motor neurone disease is described. Topical and oral steroids together with azathioprine and mesalazine suppositories controlled the bowel symptoms but did not improve the neurological deficit. Subsequently, the antiglutamate agent riluzole improved the mobility of his tongue. The close temporal relationship and relative infrequency of both these conditions in a Malaysian population along with the recognised association between ulcerative colitis and other neurological conditions deserve careful consideration as to whether a common denominator is involved. Documentation of coexistence of both disorders in a single patient is important in case similar associations are reported in future.

Leber's congenital amaurosis with anterior keratoconus in Pakistani families is caused by the Trp278X mutation in the AIPL1 gene on 17p

BACKGROUND

Leber's congenital amaurosis (LCA) represents the earliest and severest form of retinal dystrophy leading to congenital blindness. A total of 20% of children attending blind schools have this disease. LCA has a multigenic basis and is proving central to our understanding of the development of the retina. We describe the clinical and molecular genetic features of four inbred pedigrees from neighbouring remote villages in northern Pakistan, in which some of the affected members have concurrent keratoconus.

METHODS

History-taking and physical and eye examinations were performed in the field. Venipuncture, DNA extraction, studies of linkage to known LCA genes, automated sequencing and polymorphism analyses for haplotype assessments were done.

RESULTS

We examined 12 affected and 15 unaffected family members. By history, there were an additional nine blind people in the four pedigrees. In each pedigree a consanguineous marriage was evident. We found a homozygous nonsense mutation in the AIPL1 gene, which replaces a tryptophan with a stop codon (Trp278X). The phenotype is severe and variable, despite the common molecular genetic etiology in each family. Affected patients had hand motion to no light perception vision and fundus findings ranging from maculopathy to diffuse pigmentary retinopathy. Three affected members had definite keratoconus, and two were suspects based on mild cone formation in the cornea of at least one eye.

INTERPRETATION

We have identified four Pakistani families with a severe form of LCA that is associated with severe keratoconus in some affected members. The molecular etiology in all four families is a homozygous nonsense mutation, Trp278X, in the photoreceptor-pineal gene AIPL1. To our knowledge, this is one of the first phenotype-genotype correlations of AIPL1-associated LCA.

Laboratory accidents--a matter of attitude

This is a prospective study on accidents occurring in the Pathology laboratories of Hospital Ipoh over the 3-year period from January 1996 to October 1999. 15 mishaps were recorded. The location of the accidents were the histology (40%), microbiology (33%), haematology (20%) and cytology (7%) laboratories. No mishaps were reported from the clinical chemistry, blood bank and outpatient laboratories. Cuts by sharp objects were the most common injuries sustained (47%) followed by splashes and squirts by fluid such as blood or chemicals (27%). There was 1 case each of contact with biohazardous fluid, burn, allergy and accidental drinking of disinfectant. 67% of the accidents involved medical laboratory technicians, 20% involved attendants and the rest were medical officers and the junior laboratory technicians. Although the accidents reported appeared trivial, it is vital to document them and bring them to the attention of all concerned in the laboratory, in order to prevent major accidents and also because of medico-legal implications. The role of the Laboratory Safety Committee cannot be overemphasised. Modification of staff attitude is considered an important remedial goal.

Tissue engineering of pulmonary heart valves on allogenic acellular matrix conduits: in vivo restoration of valve tissue

BACKGROUND

Tissue engineering using in vitro-cultivated autologous vascular wall cells is a new approach to biological heart valve replacement. In the present study, we analyzed a new concept to process allogenic acellular matrix scaffolds of pulmonary heart valves after in vitro seeding with the use of autologous cells in a sheep model.

METHODS AND RESULTS

Allogenic heart valve conduits were acellularized by a 48-hour trypsin/EDTA incubation to extract endothelial cells and myofibroblasts. The acellularization procedure resulted in an almost complete removal of cells. After that procedure, a static reseeding of the upper surface of the valve was performed sequentially with autologous myofibroblasts for 6 days and endothelial cells for 2 days, resulting in a patchy cellular restitution on the valve surface. The in vivo function was tested in a sheep model of orthotopic pulmonary valve conduit transplantation. Three of 4 unseeded control valves and 5 of 6 tissue-engineered valves showed normal function up to 3 months. Unseeded allogenic acellular control valves showed partial degeneration (2 of 4 valves) and no interstitial valve tissue reconstitution. Tissue-engineered valves showed complete histological restitution of valve tissue and confluent endothelial surface coverage in all cases. Immunohistological analysis revealed cellular reconstitution of endothelial cells (von Willebrand factor), myofibroblasts (alpha-actin), and matrix synthesis (procollagen I). There were histological signs of inflammatory reactions to subvalvar muscle leading to calcifications, but these were not found in valve and pulmonary artery tissue.

CONCLUSIONS

The in vitro tissue-engineering approach using acellular matrix conduits leads to the in vivo reconstitution of viable heart valve tissue.

Short latency visual evoked potentials in occupational exposure to organic solvents

OBJECTIVES

Short latency visual evoked potentials (SVEP), in response to high-intensity flashes from light emitting diodes (LED), were used to detect subclinical effects along the visual pathway in four groups of subjects with different levels of exposure to gasoline, all within legally acceptable limits.

METHODS

Potentials and exposure levels were obtained from 31 subjects with different occupational exposure levels to gasoline fumes, as well as from 17 non-exposed control subjects. SVEP were recorded from four electrode sites (infra-orbital, Cz, Pz, Oz), in response to flashes presented to each eye in turn from goggle-mounted LEDs. SVEP components were defined after digital filtering, which eliminated the high-frequency oscillatory potentials and accentuated five major components: a periocular P30, attributed to the retina; a fronto-central N50, attributed to the optic nerve; centro-parietal P65 and N85, attributed to the optic tracts and radiation; and an occipital, cortical P105.

RESULTS

The latencies of successive SVEP components of the exposed subjects showed a significant latency prolongation compared to controls, beginning with activity attributed to the optic nerve and increasing cumulatively with the later components. Retinal components were not affected by the exposure to organic solvents. Among the exposed groups, differences in latency prolongation corresponded to occupational exposure.

CONCLUSION

The low-frequency components of SVEP were reliably measured and proved to be sensitive to subclinical effects of organic solvents on conduction along the visual pathway. These components are likely to be sensitive to other subcortical visual pathway lesions, but their clinical promise needs further verification.

Evaluation of nutritional status among a group of young Chinese adults in Kuala Lumpur, Malaysia

A nutritional status study was carried out among a group of young Chinese adults, aged between 19 and 25, in Kuala Lumpur, Malaysia. Subjects comprised 108 young adults (55 women, 53 men) who were students at two institutes of higher learning. Physical characteristics were evaluated by anthropometric measurements while food intake was determined with a 3-day food record. Blood cholesterol and triglyceride were assessed using the Reflotron analyser. Birthweight was obtained from birth certificates or by proxy. The results showed that the mean body mass index (BMI) for men and women was 21.4 ± 3.3 and 20.0 ± 2.0, respectively, indicating normal weight. Further analysis of BMI classification demonstrated that 28% of men and 39% of women were underweight, 11% of men and 2% of women were overweight while 2% of men were obese. Mean waist-to-hip ratio showed that the subjects had a low risk of developing cardiovascular disease (0.72 ± 0.03 women; 0.81 ± 0.05 men). Mean energy intake was 8841 ± 1756 kJ per day for men and 6426 ± 1567 kJ per day for women. Closer analysis of energy intake of the subjects showed that 86% of men and 91% of women were consuming below the Malaysian recommendation for energy. Nutrients found to be deficient in at least one third of women were calcium, vitamin A, niacin and iron. Mean cholesterol intake in the diet was 278.7 ± 108.7 mg in men and 207.0 ± 82.5 mg in women and there was a significant difference between genders. Blood cholesterol and triglyceride levels were 3.88 ± 0.76 mmol/L and 1.08 ± 0.33 mmol/L, respectively in men, while these levels were lower in women, 3.87 ± 0.80 mmol/L for cholesterol and 0.99 ± 0.29 mmol/L for triglyceride. A general trend of higher mean blood cholesterol and triglyceride levels was shown in adults who were born with lower birthweights.

Analysis of N(alpha)-methylhistamine by gas chromatography-mass spectrometry

A gas chromatography-electron capture mass spectrometry assay has been developed for the histamine H3 receptor agonist, N(alpha)-methylhistamine (N(alpha)-MH). The assay is linear from 50 pg-10 ng, with a limit of detection of 50 pg/ml for gastric juice and plasma, and 50 pg/sample for bacteria (10(7)-10(8) CFU) and gastric tissue (5-10 mg wet weight). The limits of quantification are 100 pg/ml for gastric juice (%RSD=1.4) and plasma (%RSD=9.4), and 100 pg/sample for bacteria (%RSD=3.9) and tissue (%RSD=5.8). N(alpha)-MH was not present in human plasma, but low levels (1.4 ng/ml and 0.4 ng/ml) were detected in two samples of human gastric juice obtained from patients infected with Helicobacter pylori.

A single-fiber in vitro motility assay. In vitro sliding velocity of F-actin vs. unloaded shortening velocity in skinned muscle fibers

We describe an approach that allows us to form a micro in vitro motility assay with as little myosin as can be retrieved from a short (approximately 10 mm) segment of a single skinned skeletal muscle fiber (diameter some 100 microm). Myosin is directly extracted from the single fiber segment by a high ionic strength solution in the presence of MgATP, and the extracted myosin is immediately applied to a miniaturized flow cell that has been pretreated with BSA. The observed sliding velocities of fluorescently labeled F-actin are essentially identical with those reported in the literature. Since at the single fiber level most muscle fibers contain only a single myosin heavy chain isoform this approach allows us to determine without additional purification steps, the sliding velocity driven by myosins with different heavy chain isoforms. In addition, this approach can be used to directly correlate under identical experimental conditions unloaded shortening velocity measured in segments of skinned muscle fibers with the in vitro sliding velocity of fluorescently labeled F-actin by extraction of myosin from the same skinned fibers. Such direct correlation was performed with different myosin heavy chain isoforms as well as at different temperatures and ionic strengths. Under all conditions studied, unloaded shortening velocity was 4- to 8-fold faster than sliding velocity in the motility assay even at high temperature (22 degrees C) and ionic strengths >50 mM. This suggests that sliding velocity in the motility assay is limited by additional factors beyond those thought to limit velocity of unloaded shortening in muscle fibers. One such factor might be unspecific ionic interactions between F-actin and the substrate in the motility assay resulting in somewhat higher sensitivity for ionic strength of sliding velocity in the motility assay. This might become of special relevance when using in vitro sliding velocity in assessing functional consequences of mutations involving charged residues of actin or myosin.

Priming of platelet alphaIIbbeta3 by oxidants is associated with tyrosine phosphorylation of beta3

Reactive oxygen species play an important role at the site of vascular injuries and arterial thromboses. We studied the mechanism mediating platelet aggregation induced by H2O2, a major cellular oxidant. Exposure to H2O2 triggered platelet aggregation, but only when the platelets were stirred. Strong platelet aggregation induced99032416 required the presence of the tyrosine phosphatase inhibitor sodium orthovanadate (NaVO4) and was dependent on the participation of integrin alphaIIbbeta3 (glycoprotein IIb-IIIa). A specific inhibitor of alphaIIbbeta3 blocked platelet aggregation induced by H2O2 and NaVO4, thus confirming that aggregation requires this receptor. In the presence of H2O2 and NaVO4, multiple platelet substrates were phosphorylated on tyrosine. Such tyrosine kinase response was necessary but not sufficient to activate alphaIIbbeta3, as detected by binding of soluble fibrinogen to platelets. Stirring of the platelets exposed to H2O2 and NaVO4 was also needed to allow for binding of fibrinogen to alphaIIbbeta3. The tyrosine kinase inhibitor genistein was able to block platelet aggregation induced by H2O2 and NaVO4, thus confirming that tyrosine kinase activity was needed to trigger alphaIIbbeta3 activation on stirring. N-Acetyl-L-cysteine, a cell-permeant antioxidant, blocked the tyrosine phosphorylation of platelet substrates and also the platelet aggregation induced by H2O2 and NaVO4. We found that beta3 was phosphorylated on tyrosine in platelets exposed to H2O2 and NaVO4, even in the absence of aggregation. Hence, tyrosine phosphorylation of beta3 might contribute to the "priming" of alphaIIbbeta3 induced by H2O2 and NaVO4, whereby the receptor can become activated on stirring of the platelets.

Haemophagocytosis in typhoid fever

This report deals with a young man who developed features of haemophogocytosis during the course of typhoid fever. The pertinent clinical and laboratory features of typhoid-associated haemophagocytosis are discussed. The need for blood component replacement therapy in addition to specific anti-microbials to treat haemophagocytosis complicating typhoid fever is stressed.

Oesophagostomiasis in man: report of the first Malaysian case with emphasis on its pathology

This paper describes the first Malaysian case of oesophagostomiasis. The patient was an 8-year-old Malay boy who presented to Ipoh General Hospital, Perak with abdominal pain and weight loss. Examination revealed multiple cavitated pseudotumours of the colon. A hemicolectomy was performed. Examination of the lesions revealed Oesophagostomum worms in the necrotic centres. The differential diagnoses and the pathology caused by Oesophagostomum are discussed. A brief review of the available literature is presented.

Traumatic posterior atlantoaxial dislocation without neurological deficit: case report

A case is presented in which a patient sustained a closed head injury with subsequent acute subdural hematoma and delayed posterior dislocation of the atlas without fracture of the odontoid process and with an intact C-1 arch. The subdural hematoma was treated operatively. The atlas dislocation was managed with closed reduction without manipulation and subsequent posterior fusion of C-1, C-2, and C-3. The patient was intact neurologically on admission and remained so throughout his hospitalization.