Refining quantitative fluorescent polymerase chain reaction for prenatal detection of X chromosomal anomalies in the major Southeast Asian populations

INTRODUCTION

This study aimed to refine the current quantitative fluorescent polymerase chain reaction (QF-PCR) screen to detect X chromosome anomalies for prenatal diagnosis in the major Southeast-Asian populations.

METHODS

100 amniotic fluid samples from Chinese, Malay and Indian origins were subjected to QF-PCR using the X chromosome markers, HPRT, X22 and AMXY, along with the autosomal marker D21S1411.

RESULTS

Out of the 100 samples tested by markers X22 and HPRT, eight samples were homozygous for both markers, of which seven were resolved by comparison with the autosomal marker D21S1411.

CONCLUSION

99 percent of samples could be tested for X chromosome copy numbers, increasing the stringency for detection of X chromosome anomalies by QF-PCR. All results were confirmed by cytogenetics.

Ozone oxidation of oestrogenic active substances in wastewater and drinking water

Ozone oxidation is proven to be an effective solution for the degradation of selected oestrogenic active substances detected in secondary wastewaters such as beta-oestradiol, oestrone, oestriol, 17-alpha-ethinyloestradiol, mestranol, daidzeine, beta-sitosterol, bisphenol A, norethisterone, 4-tert-octylphenol and 4-iso-nonylphenol, up to their limit of detection. The matrix-effect of wastewater was investigated performing ozone experiments under batch mode and continuous mode using drinking water and a wastewater issued from a local plant both spiked with the non-detected substances. The results obtained indicate that the wastewater matrix greatly affects the kinetics of ozone reaction with these substances but does not really change the related reactivity scale. The ozone dose corresponding to the full conversion of target EDCs consequently increases as their oxidation takes place competing with reactions of background pollutants represented by the COD and DOC content. However, a usual dose close to 12 mg/L was found sufficient to provide high degradation yields for all substances studied while 35% of COD was removed. This is a contribution to the numerous current works focused on technologies able to improve the quality of water discharged from wastewater treatment plants, both considering conventional parameters and emerging contaminants.

Predictors of in-hospital mortality for intracerebral hemorrhage: a hospital-based study in Pakistani adults

INTRODUCTION

Intracerebral hemorrhages (ICHs) comprise 5% to 30% of all strokes with a case fatality rate of 30% to 50%. With an increasing elderly population, nontraumatic ICH is likely to present as a recurring medical emergency in Pakistan. There is scarce documentation in Pakistan regarding the predictors for mortality in patients with ICH that can guide physicians in their management. We conducted a hospital-based study to determine the predictors of in-hospital mortality from ICH in patients admitted to a tertiary care facility.

MATERIALS AND METHODS

We reviewed case records of patients above 17 years admitted to The Aga Khan University Hospital, Karachi, Pakistan, between July 1995 and December 1997, with the primary diagnosis of ICH confirmed on computed tomography scanning. Clinical and risk factors were also evaluated.

RESULTS

The data of 221 patients was analyzed. Seventy-one (32%) patients died during hospital stay, half of whom died during the first 2 days of hospitalization. Patients who died during hospital stay were more likely on admission to have intraventricular extension of the primary hemorrhage (odds ratio = 10.6, P < .01), a Glasgow Coma Score less than 12 on admission (odds ratio = 4.8, P < .01), and a systolic blood pressure greater than or equal to 180 mm Hg (odds ratio = 2.7, P = .03).

CONCLUSIONS

Our study suggests that Glasgow Coma Score and intraventricular extension are predictors of acute mortality, consistent with published results. Elevated systolic blood pressure at admission, also found to be a predictor of acute mortality from ICH, may be explained alternatively by internal and external stroke-induced stress factors. The actual mechanisms for high admission systolic blood pressure remain unclear.

Semiautomatic volume of interest drawing for 18F-FDG image analysis—method and preliminary results

PURPOSE

Functional imaging of cancer adds important information to the conventional measurements in monitoring response. Serial (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET), which indicates changes in glucose metabolism in tumours, shows great promise for this. However, there is a need for a method to quantitate alterations in uptake of FDG, which accounts for changes in tumour volume and intensity of FDG uptake. Selection of regions or volumes [ROI or volumes of interest (VOI)] by hand drawing, or simple thresholding, suffers from operator-dependent drawbacks.

MATERIALS AND METHODS

We present a simple, robust VOI growing method for this application. The method requires a single seed point within the visualised tumour and another in relevant normal tissue. The drawn tumour VOI is insensitive to the operator inconsistency and is, thus, a suitable basis for comparative measurements. The method is validated using a software phantom. We demonstrate the use of the method in the assessment of tumour response in 31 patients receiving chemotherapy for various carcinomas.

RESULTS

Valid assessment of tumour response could be made 2-4 weeks after starting chemotherapy, giving information for clinical decision making which would otherwise have taken 9-12 weeks. Survival was predicted from FDG-PET 2-4 weeks after starting chemotherapy (p = 0.04) and after 9-12 weeks FDG-PET gave a better prediction of survival (p = 0.002) than CT or MRI (p = 0.015).

CONCLUSIONS

FDG-PET using this method of analysis has potential as a routine tool for optimising use of chemotherapy and improving its cost effectiveness. It also has potential for increasing the accuracy of response assessment in clinical trials of novel therapies.

FastFISH: technique for ultrarapid fluorescence in situ hybridization on uncultured amniocytes yielding results within 2 h of amniocentesis

Rapid aneuploidy detection methods allow prenatal diagnosis results to be released within 48 h, but not on the same day as the invasive test. We aimed to develop a rapid fluorescence in situ hybridization (FISH) method (FastFISH) that releases accurate results on the same day as amniocentesis. FastFISH was optimized to be completed within 2 h of sample collection using CEP and LSI probes for chromosomes 13, 18, 21, X, Y and DiGeorge syndrome (DGS). The technique was tested on 100 consecutive amniotic fluid samples in a blinded study. It was also validated as a 1-day molecular genetic test on three representative fetal tissue samples: chorionic villus, amniotic fluid and fetal blood. In the blinded study, FastFISH results were ready within 2 h of sample collection. Of the 100 amniotic fluid samples, 49 male and 50 female fetuses were identified. One fetus was 47, XXY (Klinefelter syndrome). Three fetuses had trisomy 21. One fetus suspected of DGS by ultrasound was identified as normal. Results of FastFISH analyses in all 100 cases were concordant with their karyotypes (100% accuracy; lower 95% CI, 97.05%). In the 1-day test validation, all results were released on the same day and were concordant with their respective karyotypes. FastFISH allows results to be released on the same day as amniocentesis. It represents the necessary development for a 1-day prenatal diagnosis service.

Novel tissue remodelling roles for human recombinant erythropoietin

rHuEPO (recombinant human erythropoietin) is a haemopoietic growth factor and a primary regulator of erythropoiesis that is used for the treatment of chronic anaemia associated with RA (rheumatoid arthritis). Erythropoietin also appears to modulate a broad array of cellular processes, including progenitor stem-cell development, cellular integrity, angiogenesis and oxidative damage. These diverse activities suggest the exciting possibility of multiple roles for rHuEPO therapy in a variety of disorders other than RA, including cerebral ischaemia, myocardial infarction, chronic congestive heart failure and cancer. Thus it appears that rHuEPO may be a pleiotropic agent, capable of influencing tissue remodelling independently of its established erythropoietic role. Whereas these effects may be largely beneficial, dose-related side effects could have implications for the safe therapeutic use of rHuEPO and its illegal use as a performance-enhancing agent in endurance sports.

Simulation of pulp mill wastewater recycling after tertiary treatment

The aim of this work is to study the possibilities of effluent recycling in a bleached Kraft pulp mill, for a better water management. To avoid problems associated with effluent recycling (corrosion, odors, loss in pulp and paper quality), wastewaters have to be treated before recycling. This study is particularly focused on organic matter removal. Several treatments are applied on a biological secondary effluent: adsorption on activated carbon, coagulation with ferric chloride or alum sulfate, precipitation with lime, ozonation and catalytic ozonation. These techniques are compared in terms of COD (Chemical Oxygen Demand) removal. Catalytic ozonation is finally chosen as the most effective solution to achieve 50% of COD removal in the effluent. The characteristics of the effluent treated according to this technique are then used to simulate the impact of its reuse in the process for pulp production. The study is focused on the changes in these parameters in the various stages of bleaching and final washing when water is replaced by the wastewater treated or directly issued from the wastewater treatment plant. The simulation demonstrates the need of a tertiary treatment to eliminate COD in order to avoid possible reactant overconsumption and decrease in pulp brightness. Chloride and sulfate ions which could cause corrosion should also be removed.

Purification and characterization of a metacestode cysteine proteinase from Taenia solium involved in the breakdown of human IgG

Infection of the central nervous system by Taenia solium cysticerci is the cause of human neurocysticercosis, a major neurological infection in the Third World and an emerging infectious disease in the United States. We previously isolated a cysteine proteinase from cysticerci of Taenia crassiceps and demonstrated that it degrades human IgG in vitro. We have now isolated a 48 kDa thiol-dependent proteinase from T. solium. The T. solium enzyme also degrades human IgG, but does not significantly degrade albumin. IgG degradation was inhibited by cysteine proteinase inhibitors, but not significantly by inhibitors of aspartic, serine, or metalloproteinases. The peptide substrate specificity and pH optimum resemble cathepsin L. The Km for the peptide substrate Z-Phe-Arg-AFC was calculated to be 7.0 x 10(-6) M, the Kcat was 1.98 x 10(-5) s(-1), and the Kcat/Km 2.84 x 10(9) M(-1) s(-1), a value which is within the diffusion control limit for highly catalytic enzymes. We propose that immunoglobulin degradation by the T. solium cysteine proteinase may play a key role in the host-parasite interface and could be employed as a target for chemotherapy.

Studies on Zn, Cu, Mg, Ca and phosphorus in maternal and cord blood

OBJECTIVE

To study the levels of trace elements zinc (Zn), copper (Cu), magnesium (Mg), calcium (Ca) and phosphorus (P) at term and to assess their correlation in maternal and cord blood.

METHODS

Fifty two women and their cord blood were studied in a tertiary care hospital in Karachi, Pakistan at the time of delivery. Zn, Cu and Mg were analyzed on atomic absorption spectrophotometer and Ca and P calorimetrically in maternal as well as cord blood. The results were compared with non-pregnant age matched controls.

RESULTS

Compared to controls, levels of Zn, Mg, and P were found higher in maternal and cord blood. Copper levels were found slightly lower in cord blood and Ca was significantly lower both in cord and maternal blood. Babies with birth weight less than 3 kg had higher levels of Zn, Cu and Mg than those with more than 3 kg, while reverse was true for the P levels. No significant difference was observed in levels of these elements on the basis of sex of the baby, except the cord blood of the male child had higher magnesium levels than female child. Similarly no significant difference was observed between levels of zinc, copper, phosphorus and magnesium in the maternal and cord blood on the basis of parity, while calcium level were significantly higher in primiparous mothers as compared to multiparous.

CONCLUSION

The results on the whole suggest that Pakistani women have higher levels of Zn, Cu, Mg and P and a marginal Ca deficiency compared to results of studies around the world.

Erythropoietin and interleukin-1beta modulate nitrite production in a Swiss 3T3 cell model of rheumatoid synovial fibroblasts

Erythropoietin (EPO), a haemopoietic growth factor and a primary regulator of erythropoiesis, is widely used to treat anaemia in various chronic complications of rheumatoid arthritis (RA). Fibroblast-like cells, found in the pannus tissue of joints, are thought to contribute to the inflammatory pathology of RA. Thus for the current study we investigated the effects of recombinant human EPO (rHuEPO) on NO metabolism, using an interleukin-1beta (IL-1beta)-stimulated Swiss 3T3 fibroblast monolayer as a model for fibroblast activity in RA. The results show that, over 3 days, both alone and in combination with the pro-inflammatory cytokine IL-1beta (10 ng/ml), rHuEPO (25 micro-units/ml) induced significant production of nitrite in cell culture supernatants. This is an indicator of NO production by nitric oxide synthase (NOS), which is a well-documented mediator of metalloproteinase-mediated tissue remodelling in RA. It therefore appears that, through modulation of NOS-dependent NO production, rHuEPO may influence remodelling of connective tissue in RA, independently of its established erythropoietic role.

CSF oligoclonal bands in multiple sclerosis

OBJECTIVE

To study the significance of oligoclonal bands in neurological disorders, specifically in Multiple Sclerosis (MS).

METHODS

The study was designed to assess the sensitivity and specificity of the test methodology of CSF electrophoresis by performing the retrospective analysis of CSF samples sent for oligoclonal bands (OCB). A total of 603 samples were received by the Clinical Laboratories, Department of Pathology of The Aga Khan University, during a period of 54 months (January 1993-June 1997). All of these samples were analyzed by performing CSF protein electrophoresis. One hundred thirty three out of 603 samples showed evidence of OCB. Out of these, 24 patients were registered with Section of Neurology, Department of Medicine, The Aga Khan University Hospital. These 24 patients were finally selected for analysis. Relevant clinical details such as age, sex and clinical presentations were recorded.

RESULTS

Fifteen (62%) out of 24 patients with positive OCB were diagnosed as cases of MS. Four (17%) patients were diagnosed to have subacute sclerosing panencephalitis (SSPE). Five (21%) patients were having other inflammatory neurological disorders.

CONCLUSION

The overall relative sensitivity and specificity for multiple sclerosis were found to be 100% and 62.5% respectively. Lack of specificity was attributed to the fact that OCB were positive in other neurological disorders as well.

Multiple MAG peptides are recognized by circulating T and B lymphocytes in polyneuropathy and multiple sclerosis

Abnormal immune responses to myelin associated glycoprotein (MAG), a component of myelin of the central and peripheral nervous system, have been suggested to play a role in the pathogenesis of multiple sclerosis (MS) and certain types of inflammatory polyneuropathy. To identify possible immunodominant MAG peptides in neuroinflammation, we examined T and B cell responses to five selected synthetic MAG peptides and myelin proteins in 21 patients with non-inflammatory polyneuropathy, 26 patients with MS, 10 optic neuritis patients and 17 healthy subjects. Enzyme-linked immunosorbent spot-forming cell assays were adopted, allowing the detection and enumeration of individual antigen responsive T and B cells in body fluids. Patients with polyneuropathy as well as those with MS had elevated levels of T and B cells recognizing MAG and its peptides. Any of the five MAG peptides under study functioned as immunodominant T and/or B cell epitope in individual subjects. None of the MAG peptides elicited a specific disease-associated T or B cell response. The enhanced T and B cell response to myelin components like MAG may play some role in initiation and/or progression of these diseases, but they could also represent secondary responses associated with myelin damage and indicate tolerization rather than autoaggressive immunity.

Taenia crassiceps: androgen reconstitution of the host leads to protection during cysticercosis

The effects of testosterone, dihydrotestosterone, and 17beta-estradiol in castrated mice of both sexes infected with Taenia crassiceps cysticerci were studied. The results showed that castration and treatment with either testosterone or dihydrotestosterone before infection decreased parasite loads by 50 and 70%, respectively, while the treatment with 17beta-estradiol increased it by three times in both genders, as compared with control mice. The specific splenocyte cell proliferation and IL-2 and IFN-gamma production were depressed in infected-castrated mice of both genders, while treatment with testosterone or dihydrotestosterone produced a significant proliferation recovery and enhanced production of IL-2 and IFN-gamma. On the other hand, the humoral response was unaffected with testosterone or dihydrotestosterone restitution, while the treatment with estradiol in both genders augmented the levels of anti-cysticerci IgG, as well as IL-6 and IL-10 production. These results suggest a protective role for androgens, possibly through the stimulation of the specific cellular immunity.

What is health? Where GPs' and patients' worlds collide

Qualitative studies have highlighted the complexity of patient models of health. The present quantitative study aimed to compare general practitioners' (GPs) and patients' models of health. A questionnaire consisting of 27 'markers of health' was completed by 472 patients (response rate 78.8%) and 64 GPs (response rate 71%). The results showed that GPs and patients were comparable in their ratings of those markers relating to arousal, such as sleep, sex drive and energy and infections, such as neck glands and having lots of colds. However, in the main GPs and patients were consistently different. In particular, the patients showed a higher rating for those markers relating to digestion (e.g. appetite, bloatedness), bodily fluids (e.g. the colour and smell of urine, regularity of bowels), the condition of the tongue, hair and complexion and for more traditional medical markers (e.g. heart beat, body weight). In contrast, GPs reported higher ratings for mood and emotions. To conclude, patients appeared to hold much more diverse models of health than GPs and reported greater endorsement for markers consistent with both a humoral and medical approach to health. These results suggest that GPs and patients do not have a shared understanding of health, which has implications for the effectiveness of primary care consultations.

Immunoendocrine interactions during chronic cysticercosis determine male mouse feminization: role of IL-6

Taenia crassiceps cysticercosis results in an impressive feminization in male mice during chronic infection, characterized by increased serum estradiol levels 100 times their normal values, while those of testosterone and dihydrotestosterone are decreased by 85 and 95% respectively. Concomitantly, the levels of follicle-stimulating hormone and IL-6 are increased 70 and 90 times their normal values in the infected male mice. Since a specific Th1/Th2 shift of the immune response has been previously reported during the chronic infection, and this shift may be associated with the feminization process, we proposed that this shift is induced by immunoendocrine interactions during the disease, and this gives way to a change in the initial resistance to the infection in the male mice, which become as susceptible as female mice. To confirm this hypothesis, we depleted immune system activity in two different ways: total body irradiation and neonatal thymectomy. Our results show that when immune system activity is depleted using either strategy, the male mice do not feminize, and the levels of follicle-stimulating hormone and IL-6 are inhibited. Depletion of IL-6 using IL-6(-/-) knockout mice does not produce the feminization process stated above, while restitution of the IL-6(-/-) knockout, irradiated, and thymectomized mice with murine recombinant IL-6 restores the feminization process. Expression of the IL-6 gene was found only in the testes and spleen of infected animals. Our results illustrate the importance of immunoendocrine interactions during a parasitic disease and show a possible new mechanism of parasite establishment in an initially resistant host.

In vitro effects of hypothalamic-pituitary-adrenal axis (HPA) hormones on Schistosoma mansoni

The effects of in vitro treatment of cercariae, schistosomula, and adult worms of Schistosoma mansoni with 4 hypothalamic-pituitary-adrenal (HPA) axis hormones are described. Dehydroepiandrosterone (DHEA) had the strongest effect on viability. Cercariae were more susceptible to this hormone than schistosomula and adults. Mechanically transformed schistosomula showed 100% mortality (determined microscopically by progressive internal disorganization, development of lucent areas in the cytoplasm, and progressive loss of motility) after 48 hr, whereas physiologically induced schistosomula were more resistant, maintaining viability for up to 5 days of exposure. Males were considerably less sensitive than females to the lethal action of DHEA. When adult worms were paired, DHEA lethality was markedly reduced, with viability beginning to decrease only after 4 days in culture. Cortisol reduced the viability of each of the stages tested about equally. Corticotropin-releasing hormone (CRH) and adrenocorticotropin (ACTH) did not affect the viability of any stage. DHEA and cortisol significantly inhibited in vitro oviposition, whereas CRH and ACTH did not. DHEA and cortisol exerted their effects on schistosome viability and oviposition in a concentration-dependent manner. These results suggest possible new avenues for the control of schistosomiasis.

Ozone treatment for biorefractory COD removal

A two case study of industrial wastewater treatment is reported in order to prove the suitability of ozonation for biorefractory COD removal. The ozone application as an end treatment is shown to provide an excellent oxidation yield of organic matter in a landfill leachate. The combination of ozonation and fixed bed biofilm process appears quite effective for the post-treatment of two biological effluents from paper industry.

Taenia solium: a cysteine protease secreted by metacestodes depletes human CD4 lymphocytes in vitro

Excreted/secreted products from Taenia solium metacestodes cultured in vitro were analyzed for peptidase activity using peptide substrates Z-Phe-Arg-AFC, Arg-AFC, and Z-Gly-Gly-Arg-AFC and zymography studies. Specific inhibitor profiles revealed mainly cysteine and metalloprotease activities. Hydrolysis of substrate Z-Phe-Arg-AFC was augmented by the addition of L-cysteine and acid pH, consistent with cysteine protease activity. Cysteine protease activity was more prominent in supernatants from living metacestodes cultured in PBS than in either RPMI or RPMI plus fetal calf serum and was proportional to the number of metacestodes. Flow cytometry analysis showed depletion of human T lymphocytes cultured with living T. solium metacestodes. CD4(+) expression was significantly decreased when metacestode E/S products and L-cysteine were added to lymphocyte cultures (P = 0.027). This peptidase activity was inhibited by E-64 indicating that the depletion of CD4(+) cells was due to cysteine protease activity. Thus, T. solium metacestodes produce excretory/secretory proteases. These enzymes may cleave molecules critical for the host immune response allowing the parasites to survive in the host tissues.

CT and MR imaging in young stroke patients

BACKGROUND

This study investigates the role of CT and MR imaging in the diagnosis and management of young stroke patients.

METHODS

CT scan findings of 108 patients and MR findings of 30 patients between 15-45 years of age were reviewed retrospectively. The variables included the territory of infarct on CT and MR imaging, the cortical distribution and size of infarct.

RESULTS

About 80% of the patients had infarcts of the carotid territory and 20% the vertebro-basilar distribution. More than half of the infarcts were cortical (56%). The yield of MR imaging was much higher for deeper structures such as basal ganglia, thalamus and brainstem. In half the cases, the infarct size was more than 3 cm.

CONCLUSION

The ratio of carotid to vertebro-basilar infarcts was similar to that reported previously. A large proportion of the carotid territory infarcts were cortical. Deeper infarcts were better imaged with MR scan. There was a high proportion of large infarcts.

Ethnicity and sex differences in university students' knowledge of AIDS, fear of AIDS, and homophobia

One hundred ninety students at a southwestern urban university participated in a study that investigated ethnicity and sex differences in AIDS-related variables: AIDS knowledge, fear of AIDS, and homophobia. Analysis of data (ANOVA) revealed that African-Americans had significantly lower scores on measures of AIDS knowledge and were significantly more homophobic, compared to Caucasian students. African-Americans also had lower average AIDS knowledge scores than Hispanics. Women had a lower fear of AIDS than men. Relationships between homophobia and fear of AIDS on the one hand, and AIDS knowledge on the other hand, were low and counter-intuitive for African-Americans and Hispanics. This suggests the need for differential efforts in AIDS education programs targeting these groups.