Characterization of Gold-Enhanced Titania: Boosting Cell Proliferation and Combating Bacterial Infestation

BACKGROUND

In this study an approach was made to efficaciously synthesize gold enhanced titania nanorods by electrospinning. This study aims to address effects of gold enhanced titania nanorods on muscle precursor cells. Additionally, implant related microbial infections are prime cause of various disastrous diseases. So, there is predictable demand for synthesis of novel materials with multifunctional adaptability.

METHODS

Herein, gold nanoparticles were attached on titania nanorods and described using many sophisticated procedures such as XRD, SEM, EDX and TEM. Antimicrobial studies were probed against Gram-negative Escherichia coli. C2C12 cell lines were exposed to various doses of as-prepared gold enhanced titania nanorods in order to test in vitro cytotoxicity and proliferation. Cell sustainability was assessed through Cell Counting Kit-8 assay at regular intervals. A phase-contrast microscope was used to examine morphology of exposed C2C12 cells and confocal laser scanning microscope was used to quantify cell viability.

RESULTS

The findings indicate that titania nanorods enhanced with gold exhibit superior antimicrobial efficacy compared to pure titania. Furthermore, newly synthesized gold-enhanced titania nanorods illustrate that cell viability follows a time and concentration dependent pattern.

CONCLUSION

Consequently, our study provides optimistic findings indicating that titania nanorods adorned with gold hold significant potential as foundational resource for developing forthcoming antimicrobial materials, suitable for applications both in medical and biomedical fields. This work also demonstrates that in addition to being extremely biocompatible, titania nanorods with gold embellishments may be used in a range of tissue engineering applications in very near future.

Nanofibers and Nanotextured Materials: Design Insights, Bactericidal Mechanisms and Environmental Advances

Antibiotic resistance is rising and poses a serious threat to human health on a worldwide scale. It can make it more difficult to cure common infections, raise medical expenditures, and increase mortality. In order to combat the development of biofilms and treat fatal bacterial infections, multifunctional polymeric nanofibers or nanotextured materials with specific structural features and special physiochemical capabilities have become a crucial tool. Due to the increased antibiotic resistance of many diseases, nanofibers with antibacterial activity are essential. Electrospinning is a flexible process able to produce fine fibers with specified properties by modifying variables such as the concentration of the solution, the feed flow, and the electric voltage. Substantial advancements have been made regarding the formation of nanofibers or nanotextured materials for a variety of applications, along with the development of electrospinning techniques in recent years. Using well-defined antimicrobial nanoparticles, encapsulating traditional therapeutic agents, plant-based bioactive agents, and pure compounds in polymer nanofibers has resulted in outstanding antimicrobial activity and has aided in curing deadly microbial infections. A plethora of studies have revealed that electrospinning is an effective technique for the production of antimicrobial fibers for the environmental, biomedical, pharmaceutical, and food sectors. Nevertheless, numerous studies have also demonstrated that the surface characteristics of substrates, such as holes, fibers, and ridges at the nanoscale, have an impact on cell proliferation, adhesion, and orientation.

Beyond survival: unraveling the adaptive mechanisms of cucurbit weeds to salt and heavy metal stress through biochemical and physiological analyses

Salt stress and heavy metal are instigating hazard to crops, menace to agricultural practices. Single and combined stresses affecting adversely to the growth and metabolism of plants. To explore salt and heavy metal resistant plant lines as phytoremediants is a need of time. Physiological responses are main adaptive responses of the plants towards stresses. This response varies with species and ecotype as well as type and level of stress. Two cucurbit weeds from two ecotypes were selected to evaluate their physiological adaptations against independent and combined stresses of various levels of salt (NaCl) and heavy metal (NiCl2). Various physiological parameters like water potential, osmotic potential, pressure potential, CO2 assimilation rate, stomatal conductance, chlorophyll a and b, carotenoids, and production of adaptive chemicals like SOD, CAT, proteins, sugars and proline were studied. Citrullus colocynthis showed more adaptive response than Cucumis melo agrestis and desert ecotype was more successful than agricultural ecotype against stresses.

Production of Ceramics/Metal Oxide Nanofibers via Electrospinning: New Insights into the Photocatalytic and Bactericidal Mechanisms

Environmental pollution is steadily rising and is having a negative influence on all living things, especially human beings. The advancement of nanoscience in recent decades has provided potential to address this issue. Functional metal oxide nanoparticles/nanofibers have been having a pull-on effect in the biological and environmental domains of nanobiotechnology. Current work, for the first time, is focusing on the electrospinning production of Zr_0.5Sn_0.5TiO₃/SnO₂ ceramic nanofibers that may be utilized to battle lethal infections swiftly and inexpensively. By using characterizations like XRD, FT-IR, FESEM, TEM, PL, and UV-Vis-DRS, the composition, structure, morphology, and optical absorption of samples were determined. The minimum inhibitory concentration (MIC) approach was used to investigate the antibacterial activity. Notably, this research indicated that nanofibers exert antibacterial action against both Gram-positive and Gram-negative bacteria with a MIC of 25 µg/mL. Furthermore, negatively charged E. coli was drawn to positively charged metal ions of Zr_0.5Sn_0.5TiO₃/SnO₂, which showed a robust inhibitory effect against E. coli. It was interesting to discover that, compared to pure TiO₂, Zr_0.5Sn_0.5TiO₃/SnO₂ nanofibers revealed increased photocatalytic activity and exceptional cyclability to the photodegradation of Rhodamine B. The composite completely degrades dye in 30 min with 100% efficacy and excellent (97%) reusability. The synergetic effects of Zr_0.5Sn_0.5TiO₃ and SnO₂ may be responsible for increased photocatalytic and bactericidal activity.

Bismuth Vanadate Decked Polyaniline Polymeric Nanocomposites: The Robust Photocatalytic Destruction of Microbial and Chemical Toxicants

Functional materials have long been studied for a variety of environmental applications, resource rescue, and many other conceivable applications. The present study reports on the synthesis of bismuth vanadate (BiVO₄) integrated polyaniline (PANI) using the hydrothermal method. The topology of BiVO₄ decked PANI catalysts was investigated by SEM and TEM. XRD, EDX, FT-IR, and antibacterial testing were used to examine the physicochemical and antibacterial properties of the samples, respectively. Microscopic images revealed that BiVO₄@PANI are comprised of BiVO₄ hollow cages made up of nanobeads that are uniformly dispersed across PANI tubes. The PL results confirm that the composite has the lowest electron-hole recombination compared to others samples. BiVO₄@PANI composite photocatalysts demonstrated the maximum degradation efficiency compared to pure BiVO₄ and PANI for rhodamine B dye. The probable antimicrobial and photocatalytic mechanisms of the BiVO₄@PANI photocatalyst were proposed. The enhanced antibacterial and photocatalytic activity could be attributed to the high surface area and combined impact of PANI and BiVO₄, which promoted the migration efficiency of photo-generated electron holes. These findings open up ways for the potential use of BiVO₄@PANI in industries, environmental remediation, pharmaceutical and medical sectors. Nevertheless, biocompatibility for human tissues should be thoroughly examined to lead to future improvements in photocatalytic performance and increase antibacterial efficacy.

Nanotextured CeO2-SnO2 Composite: Efficient Photocatalytic, Antibacterial, and Energy Storage Fibers

Bacterial infections remain a serious and pervasive threat to human health. Bacterial antibiotic resistance, in particular, lowers treatment efficacy and increases mortality. The development of nanomaterials has made it possible to address issues in the biomedical, energy storage, and environmental fields. This paper reports the successful synthesis of CeO₂-SnO₂ composite nanofibers via an electrospinning method using polyacrylonitrile polymer. Scanning and transmission electron microscopy assessments showed that the average diameter of CeO₂-SnO₂ nanofibers was 170 nm. The result of photocatalytic degradation for methylene blue dye displayed enhanced efficiency of the CeO₂-SnO₂ composite. The addition of SnO₂ to CeO₂ resulted in the enhancement of the light absorption property and enriched charge transmission of photoinduced electron-hole duos, which conspicuously contributed to momentous photoactivity augmentation. Composite nanofibers exhibited higher specific capacitance which may be accredited to the synergism between CeO₂ and SnO₂ particles in nanofibers. Furthermore, antibacterial activity was screened against Escherichia coli and CeO₂-SnO₂ composite nanofibers depicted excellent activity. The findings of this work point to new possibilities as an electrode material in energy storage systems and as a visible-light-active photocatalyst for the purification of chemical and biological contaminants, which would substantially benefit environmental remediation processes.

Recent trends using natural polymeric nanofibers as supports for enzyme immobilization and catalysis

All the disciplines of science, especially biotechnology, have given continuous attention to the area of enzyme immobilization. However, the structural support made by material science intervention determines the performance of immobilized enzymes. Studies have proven that nanostructured supports can maintain better catalytic performance and improve immobilization efficiency. The recent trends in the application of nanofibers using natural polymers for enzyme immobilization have been addressed in this review article. A comprehensive survey about the immobilization strategies and their characteristics are highlighted. The natural polymers, e.g., chitin, chitosan, silk fibroin, gelatin, cellulose, and their blends with other synthetic polymers capable of immobilizing enzymes in their 1D nanofibrous form, are discussed. The multiple applications of enzymes immobilized on nanofibers in biocatalysis, biosensors, biofuels, antifouling, regenerative medicine, biomolecule degradation, etc.; some of these are discussed in this review article.

Chitosan-Functionalized Hydroxyapatite-Cerium Oxide Heterostructure: An Efficient Adsorbent for Dyes Removal and Antimicrobial Agent

The current research intended to employ a facile and economical process, which is also ecofriendly to transform camel waste bones into novel heterostructure for cleansing of diverse waste waters. The bones of camel were utilized for preparation of hydroxyapatite by hydrothermal method. The prepared hydroxyapatite was applied to the synthesis of cerium oxide-hydroxyapatite coated with natural polymer chitosan (CS-HAP-CeO₂) heterostructure. Being abundant natural polymer polysaccharide, chitosan possesses exceptional assets such as accessibility, economic price, hydrophilicity, biocompatibility as well as biodegradability, therefore style it as an outstanding adsorbent for removing colorant and other waste molecules form water. This heterostructure was characterized by various physicochemical processes such as XRD, SEM-EDX, TEM, and FT-IR. The CS-HAP-CeO₂ was screened for adsorption of various industrially important dyes, viz., Brilliant blue (BB), Congo red (CR), Crystal violet (CV), Methylene blue (MB), Methyl orange (MO), and Rhodamine B (RB) which are collective pollutants of industrial waste waters. The CS-HAP-CeO₂ demonstrated exceptional adsorption against CR dye. The adsorption/or removal efficiency ranges are BB (11.22%), CR (96%), CV (28.22%), MB (47.74%), MO (2.43%), and RB (58.89%) dyes. Moreover, this heterostructure showed excellent bacteriostatic potential for E. coli, that is liable for serious waterborne diseases. Interestingly, this work revealed that the incorporation of cerium oxide and chitosan into hydroxyapatite substantially strengthened antimicrobial and adsorption capabilities than those observed in virgin hydroxyapatite. Herein, we recycled the unwanted camel bones into a novel heterostructure, which assists to reduce water pollution, mainly caused by the dye industries.

Electrochemical regeneration of hexavalent chromium from aqueous solutions in a gas sparged parallel plate reactor

In this study anodic oxidation of Cr₂(SO₄)₃ was carried out in an air-sparged divided parallel plate cell. Variables studied were current density, Cr₂(SO₄)₃ concentration, and superficial air velocity. The rate constant of Cr₂(SO₄)₃ oxidation was found to increase with increasing current density and Cr₂(SO₄)₃ concentration. The effect of air sparging was found to depend on Cr₂(SO₄)₃ concentrations, at high Cr₂(SO₄)₃ concentration (> 0.1 M) air sparging does not affect the rate constant of the reaction denoting that the reaction is charge transfer controlled. As Cr₂(SO₄)₃ concentration decreases below 0.1 M the reaction becomes under mixed diffusion and chemical control and the rate constant increases with increasing air superficial velocity, the lower Cr₂(SO₄)₃ concentration the higher the contribution of diffusion to the reaction rate. The current efficiency of the process ranged from 20 to 85% depending on current density and Cr₂(SO₄)₃ concentration. Electrical energy consumption which ranged from 1.8 to 14.4 kW h/kg of Cr⁶⁺ was found to increase with increasing current density and decreases with increasing Cr₂(SO₄)₃ concentration. Air sparging was found to decrease electrical energy consumption in the case of dilute solutions << 0.1 M Cr₂(SO₄)₃.

Synthesis and characterization of Ag-AgVO3/Cu2O heterostructure with improved visible-light photocatalytic performance

Heterostructure Ag-AgVO3/Cu2O photocatalyst was prepared by the hydrothermal procedure. The prepared photocatalysts were characterized by different physico-chemical techniques. For Ag-AgVO3/Cu2O composites, AgVO3 shows the monoclinic phase whereas Ag and Cu2O show a cubic phase. SEM images of Ag-AgVO3/Cu2O composites illustrated that the surface of AgVO3 nanorods was covered by Ag and Cu2O nanoparticles. Ultra violet - visible diffuse reflectance spectra revealed that the calculated optical response of Ag-AgVO3/Cu2O composite was found to be 2.24 eV. Additionally, the composite catalyst demonstrated improved photo-efficiency for the decolorization of methylene blue dye compared to that of pristine AgVO3. The better performance of the composite sample can be ascribed to its high charge separation and inhibition in recombination of charges in Ag-AgVO3/Cu2O catalyst Finally, this heterostructure Ag-AgVO3/Cu2O catalyst demonstrated good stability which simply can be recycled a number of times with steadiness; thus, unwraps new possibilities for applications as innovative photocatalyst.

MO537INTERACTION OF PLASMA HOMOCYSTIENE, RENAL FUNCTION AND CARDIO-METABOLIC RISK FACTORS- AN OBSERVATION IN A RURAL POPULATION OF BANGLADESH

Background and Aims

Elevated plasma total homocystiene (tHcy) levels are associated with atherosclerotic diseases in coronary, cerebral and peripheral blood vessels. It is possible that hyperhomocysteinemia may lead to intrarenal arteriosclerotic lesions and decline in GFR or impaired renal function. Aim of this study was to elucidate the association of plasma homocystiene level with renal function and cardiovascular risk factors in rural population.

Method

A well defined rural area was selected. Study subjects were identified by computer generated random numbers after entering household listings and then Kish table was used to choose a participant. Adult subjects (≥18 years) were only included. The approached participant was explained the purpose, if consented, then given an appointment to be present at a research hospital on a separate date for clinical and biochemical evaluation. A face to face interview was conducted. Clinical history, physical examination anthropometrics were recorded on data sheet. Fasting blood sample and morning spot urine was collected. Then serum tHcy was measured by chemiluminescent microparticle immunoassay (CMIA) technology. Study population were investigated with Spot urine ACR, Fasting glucose, serum lipid profile, creatinine, homocysteinine , Folic acid and Vit B12.

Results

Early results of 234 random subjects are presented here. The mean age was 41 ± 13(18-92) years with male 33% and female 67%. Mean eGFR was 99± 26 ml/min, tHcy 11.6 ± 5.9 μmol/l, Vit B12 329 ± 187 pg/ml and Folic Acid 5.57 ± 2.63 ng/ml. A tHcy cut-off value in study subjects ≥15 μmol/l was seen in 17 % and &lt;15 μmol/l in 83%. Serum creatinine, Uric Acid, Cholesterol, LDL was significantly higher and Vit B12, Folic acid lower in tHcy ≥15 μmol/l group. Further grouping showed tHcy level was significantly higher in Vit B12&lt;200 pg/ml and Folic acid &lt;3ng/l group. Correlation studies showed homocystiene positively correlated with age, systolic blood pressure, creatinine, LDL and negatively with Folic acid and Vit B12.

Conclusion

Our findings suggest that elevated plasma homocystiene level might influence and are associated with altered markers of renal, cardiac and metabolic risk factors in rural population. Preventive approaches are required towards this issue as larger population segment belongs to rural areas.

MO111PATTERN OF CARDIAC AND RENAL RISK FACTORS PREVAILING IN HYPERTENSIVE SUBJECTS OF RURAL COMMUNITY: PRIMARY RESULTS FROM AN ONGOING SYSTEMATIC SURVEY IN BANGLADESH

Background and Aims

Hypertension is the leading entity of non communicable diseases (NCD). Some 15-30% adult population is identified suffering from hypertension at any given time worldwide. Complications of hypertension cause severe functional deficit and a major decline in quality of life for the patient and family.

This study was carried out to identify the presence and pattern of cardiac and renal risk factors influencing major morbidity and mortality in hypertensive subject by performing relevant clinical and laboratory evaluations.

Method

In this survey adult subjects were selected randomly from a defined rural area. Their demographic, anthropometric and clinical information was recorded by WHO STEP wise approach surveillance-Instrument v.3.1. Information on prevailing NCDs and related risk factor were collected on a short questionnaire by face-to-face interview. Blood Pressure (BP) was measured by digital blood pressure monitor (Omron) with standard sized cuff after 10-15 minutes of rest in sitting posture by taking mean of two readings. Systolic BP ≥140 and/or diastolic BP ≥90mmHg or subjects taking antihypertensive medications were considered for hypertension. Early morning urine and fasting blood sample was collected for glycemic profile, lipid profile, serum creatinine, eGFR (MDRD equation) and urine ACR estimations for identifying diabetes, dyslipidemia and nephropathy. Results from an early group are presented here.

Results

From surveyed population consequative 300 hypertensive subjects with 100 normotensive subjects were analyzed. Male/female distribution was 66% and 34%. Age in 75% was between 25-55 years and BMI overweight to obese in 45%. Etiology wise in 81% it was essential hypertension followed by diabetes 18% and nephropathies in rest. Mean systolic BP was 147±16 and diastolic BP 71±9 mmHg. Comparison of hypertensive vs. normotensives showed FBS 6.7±3 vs. 5.8±1.0 mmol/l, (p&lt;0.001). Lipids as cardiac markers were TG 170±107 vs. 130±76 g/dl, (p&lt;0.001); Cholesterol 195±50 vs. 180±49 g/dl, (p&lt;0.001); LDL 170±107 vs. 130±76 g/dl, (p&lt;0.04); and HDL 42±7 vs. 46±8 g/dl, (p&lt;0.001). Renal parameters like eGFR was 88±22 vs. 98±26 ml/min, (p&lt;0.001); and ACR 99±556 vs. 30±87 mg/g, (p&lt;0.04). These comparisons showed fasting hyperglycemia with most of the lipids higher and HDL lower in hypertensives. Renal parameters like eGFR was lower and albuminuria was significantly higher with similar urinary Na and K excretion in hypertensives. Other cardio renal markers like Uric Acid and hCRP was similar in both groups. Pearson’s correlations showed a positive correlation of systolic and diastolic BP with major components of cardiac, renal and metabolic risk factors.

Conclusion

It is found that hypertension is essential in nature among 81% of rural subjects. Nearly half of the study subjects are overweight. Dyslipidemia, albuminuria and low GFR is more pronounced in hypertensives in comparison to the normotensive counterparts. So, hypertension is mostly associated with adverse cardio-renal risk markers.

Influence of probiotic and yeast culture supplementation on selected biochemical and immunological parameters of growing lambs

This study was carried out to evaluate the potential effects of 90 days-long dietary supple- mentation of probiotic and yeast culture on immunity condition of lambs. Fifteen Rahmani growing male lambs (about 5 months old and 23.21±2.75 kg body weight) were randomly allo- cated to three equal groups consisting of 5 animals each. The animals in the first group, served as a control (group C), were fed a basal diet without any supplementation. The lambs in the second and third group were fed the basal diet supplemented with probiotic (group Y) or yeast culture (group YC), respectively. The probiotic consisted of live yeast (Saccharomyces cerevisae) alone, while the yeast culture was composed of Saccharomyces cerevisiae and the media on which it was grown. In group Y and YC, each lamb was supplemented daily with 0.5 g and 7.0 g of live yeast and yeast culture, respectively. Blood samples were collected before feeding the supplements and then every 15 days until the day 90th. Total and differential leucocytic counts, total protein, albumin, IgA, IgG and IgM levels were measured in blood. There were insignificant (p>0.05) variations in the levels of total and differential leucocytic counts and total protein among the groups throughout the experiment. However, significant differences (p⟨0.05) were found in globulin, IgA, IgG and IgM in both (Y) and (YC) groups, but the effect of yeast culture seems to be better than that of the probiotic. In conclusions, the obtained results indicate that the tested probiotic and yeast culture improve the immunological status of lambs.

P0835IDENTIFYING THE FREQUENCY OF CHRONIC KIDNEY DISEASE OF UNKNOWN ETIOLOGY (CKDU) IN A RURAL POPULATION OF BANGLADESH

Background and Aims

The common etiologies of CKD are diabetes, hypertension and glomerulonephritis. Prevalence of CKD of unknown (CKDu) etiology is being increasingly considered as an emerging etiology, especially in the developing countries, with environmental predisposition to hot humid climate, dehydration and toxic metal contaminations. The aim was to identify the frequency of CKDu as an etiology in a rural population with environmental exposure.

Method

In this observational study subjects were selected from a geographically defined rural population in Bangladesh. Baseline information was recorded by the translated WHO STEP wise approach surveillance- Instrument v.3.1 (Core and Expanded). Blood Pressure was measured by digital blood pressure monitor. Serum creatinine was measured by enzymatic method using assays traceable to isotope dilution mass spectrometry (IDMS). A fasting blood sample and spot urine was collected. BP ≥140/90mmHg; FBS &gt; 5.6 mmol/l and HbA1c ≥6.5%; and eGFR&lt; 60ml/min (CKD-EPI equation) or urine ACR &gt; 30mg/g was taken as diagnostic cut-offs for hypertension, diabetes and nephropathy respectively. From diagnosed CKD patients CKDu group was further identified by stepwise approach of WHO criteria as suspected and probable stages.

Results

The mean age was 41.3 ± 12.7 years with male/female ratio 37/63 in preliminary 303 study subjects. They were 12.5% diabetic, 21% hypertensive and 75% had some form of dyslipidemia. Among all 51 subjects (16.8%) were diagnosed as CKD based on single measurement of eGFR and ACR. Of these 30 study subjects (58%) met the criteria of suspected CKDu. After repeat measures of eGFR and ACR at 3 months, prevalence of CKD came down to 10.2% persisting in 31 subjects (G1:5.3%, G2:2.3% and G3: 2.6%). Of these 7 study subjects (23%) met the criteria of probable CKDu. The main etiologies of CKD among these subjects were diabetic nephropathy (48%) followed by CKDu. The frequency of CKDu in total study population as a whole was 2.3%.The pattern of environmental exposures like types of farming, use of pesticide-fertilizer, NSAIDs intakes, water sources, amount of drinking water per day, duration of work under direct sun, pattern of fish-meat intakes, etc. were not different between subjects with CKDu versus the others.

Conclusion

The prevalence of chronic kidney disease in a rural area of Bangladesh is one in ten (10.2%). Among these nearly one-fourth (23%) of the subjects belonged to probable CKDu category. This alarmingly high frequency of CKDu needs further extensive evaluation to identify the predisposing factors responsible.

The 30-year cardiovascular risk profile of South Africans with diagnosed diabetes, undiagnosed diabetes, pre-diabetes or normoglycaemia: the Bellville, South Africa pilot study

Abstract

The aim of this pilot study was to assess the 30-year risk for cardiovascular disease (CVD) in the South Africa population of mixed-ancestry in individuals with non-diabetic hyperglycaemia, and undiagnosed and self-reported diabetes. Participants were drawn from an urban community of the Bellville South suburb of Cape Town. In total, 583 subjects without a history of CVD were eligible for lifetime CVD risk estimation. Gender-specific prediction for CVD risk was calculated using the 30-year CVD interactive risk calculator. High CVD risk (> 20%) was evident in normoglycaemic and younger subjects (under 35 years). The significant predictors of CVD were sibling history of diabetes, and triglyceride, low-density lipoprotein cholesterol and glycated haemoglobin levels (p < 0.001). The high lifetime risk in normoglycaemic and younger subjects may be considered a warning that CVD might take on epidemic proportions in the near future in this country. We recommend the inclusion of education on CVD in school and university curricula.

Imaging, Spectroscopic, Mechanical and Biocompatibility Studies of Electrospun Tecoflex® EG 80A Nanofibers and Composites Thereof Containing Multiwalled Carbon Nanotubes

The present study discusses the design, development and characterization of electrospun Tecoflex® EG 80A class of polyurethane nanofibers and the incorporation of multiwalled carbon nanotubes (MWCNTs) to these materials. Scanning electron microscopy results confirmed the presence of polymer nanofibers, which showed a decrease in fiber diameter at 0.5% wt. and 1% wt. MWCNTs loadings, while transmission electron microscopy showed evidence of the MWCNTs embedded within the polymer matrix. The fourier transform infrared spectroscopy and Raman spectroscopy were used to elucidate the polymer-MWCNTs intermolecular interactions, indicating that the C-N and N-H bonds in polyurethanes are responsible for the interactions with MWCNTs. Furthermore, tensile testing indicated an increase in the Young's modulus of the nanofibers as the MWCNTs concentration was increased. Finally, NIH 3T3 fibroblasts were seeded on the obtained nanofibers, demonstrating cell biocompatibility and proliferation. Therefore, the results indicate the successful formation of polyurethane nanofibers with enhanced mechanical properties, and demonstrate their biocompatibility, suggesting their potential application in biomedical areas.

Virgin olive oil blended polyurethane micro/nanofibers ornamented with copper oxide nanocrystals for biomedical applications

Recently, substantial interest has been generated in using electrospun biomimetic nanofibers of hybrids, particularly organic/inorganic, to engineer different tissues. The present work, for the first time, introduced a unique natural and synthetic hybrid micronanofiber wound dressing, composed of virgin olive oil/copper oxide nanocrystals and polyurethane (PU), developed via facile electrospinning. The as-spun organic/inorganic hybrid micronanofibers were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis, X-ray diffraction, electron probe microanalysis, and transmission electron microscopy. The interaction of cells with scaffold was studied by culturing NIH 3T3 fibroblasts on an as-spun hybrid micronanofibrous mat, and viability, proliferation, and growth were assessed. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay results and SEM observation showed that the hybrid micronanofibrous scaffold was noncytotoxic to fibroblast cell culture and was found to benefit cell attachment and proliferation. Hence our results suggest the potential utilization of as-spun micronanoscaffolds for tissue engineering. Copper oxide–olive oil/PU wound dressing may exert its positive beneficial effects at every stage during wound-healing progression, and these micronanofibers may serve diverse biomedical applications, such as tissue regeneration, damaged skin treatment, wound healing applications, etc. Conclusively, the fabricated olive oil–copper oxide/PU micronanofibers combine the benefits of virgin olive oil and copper oxide, and therefore hold great promise for biomedical applications in the near future.

Improved supercapacitor potential and antibacterial activity of bimetallic CNFs–Sn–ZrO2 nanofibers: fabrication and characterization

The objective of our study was to develop a new class of one-dimensional Sn–ZrO₂ nanocrystal decorated CNFs.

Three-year's changes in glucose tolerance status in the Bellville South cohort: rates and phenotypes associated with progression

AIMS

To determine the phenotypes associated with progression to type 2 diabetes or worsening in glucose tolerance during a 3-year follow-up of a community-based cohort in Cape Town, South Africa.

METHODS

A total of 198 eligible subjects (72.3% women) aged 55.2 years, from the Bellville-South community were followed-up between 2008 and 2011. Baseline and follow-up data collections included glucose tolerance status, anthropometric, blood pressure, lipids, insulin, γ-glutamyltransferase, cotinine, creatinine and HbA1c. Progression in glucose tolerance status at 3-year was the composite of new-onset diabetes and any worsening in glucose tolerance status.

RESULTS

The cumulative incidence of progression in glucose tolerance status was: 16.2% (32 participants including 11 with new-onset diabetes), and increased in a stepwise fashion with the number of components of metabolic syndrome (MetS). In age and sex-adjusted logistic regression analyses, MetS [odd ratio: 3.08 (95% CI: 1.34-7.10)], HbA1c [5.26 (1.94-14.24)], HDL-cholesterol [0.05 (0.01-0.33)], γ-glutamyltransferase [1.99 (1.07-3.67)], triglycerides [1.71 (1.13-2.58)] and total/HDL-cholesterol [1.45 (1.08-1.93)] were significant predictors of progression, while borderline effects were observed for baseline glucose and diastolic blood pressure. Markers of adiposity were mostly stable or improved among non-progressors during follow-up, but deteriorated significantly among progressors, resulting in significant statistical interactions.

CONCLUSIONS

High rates of deterioration of glucose status over time were found in our population, with nearly one-fifth of them acquiring a glucose tolerance worse status within a very short follow-up. Our study extends to this setting the well-known utility of phenotypes of MetS single or in combination, in predicting worsening in glucose tolerance status.

Classy non-wovens based on animate L. gasseri-inanimate poly(vinyl alcohol): upstream application in food engineering

We explored electrospinning as a feasible and practicable mode for encapsulation and stabilization of Lactobacillus gasseri. The utilized nanocomposite was prepared using sol-gel composed of animate L. gasseri and inanimate PVA. The objective was to examine the ability of electrospinning method to protect functional properties of probiotic L. gasseri. The PVA was used as an encapsulation matrix as it is biocompatible and hydrophilic in nature thus facilitate an easy revival of bacteria. The characterization of as-spun bioproduct was done by energy-dispersive X-ray spectrometer, SEM, and TEM, whereas thermal behavior was analyzed by thermogravimetry. The viability was confirmed by traditional pour plate method and fluorescence microscopy. Furthermore, to test whether the functionality of L. gasseri was affected, the encapsulated L. gasseri were fed to mouse for colonization. Our results pointed out that encapsulated bacteria were viable for months, and their metabolism was not affected by immobilization; thus, they could be used in food engineering and trade.

Zinc oxide-doped poly(urethane) spider web nanofibrous scaffold via one-step electrospinning: a novel matrix for tissue engineering

Zinc oxide (ZnO) nanostructures have been commonly studied for electronic purposes due to their unique piezoelectric and catalytic properties; however, recently, they have been also exploited for biomedical applications. The purpose of this study was to fabricate ZnO-doped poly(urethane) (PU) nanocomposite via one-step electrospinning technique. The utilized nanocomposite was prepared by using colloidal gel composed of ZnO and PU, and the obtained mats were vacuum dried at 60 °C overnight. The physicochemical characterization of as-spun composite nanofibers was carried out by X-ray diffraction pattern, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, electron probe microanalysis, and transmission electron microscopy, whereas the thermal behavior was analyzed by thermogravimetric analysis. The viability, attachment, and proliferation of NIH 3T3 mouse fibroblast cells on the ZnO/PU composite nanofibers were analyzed by in vitro cell compatibility test. The morphological features of the cells attached on nanofibers were examined by Bio-SEM. We conclude that the electrospun nanofibrous scaffolds with unique spider nets had good biocompatibility. Cytotoxicity experiments indicated that the mouse fibroblasts could attach to the nanocomposite after being cultured. Thus, the current work demonstrates that the as-synthesized ZnO/PU hybrid nanofibers represent a promising biomaterial to be exploited for various tissue engineering applications.

Fabrication, characterization and antibacterial effect of novel electrospun TiO2 nanorods on a panel of pathogenic bacteria

This study is aimed at the synthesis and characterization of novel Titania nanorods by sol-gel electrospinning technique. The physicochemical properties of the synthesized nanorods were determined by FE-SEM, EDX, TEM, TGA and XRD. We investigated the photocatalytic activity of Titania nanorods for degrading Rhodamine 6G dye and discussed the antibacterial activity and interaction mechanism against four pathogenic bacteria viz., S. aureus, E. coli, S. typhimurium and K. pneumoniae by taking five different concentrations (5-45 microg/mL). The antibacterial effect of electrospun Titania nanorods was tested both in liquid culture and on agar plates. Our investigation reveals that the lowest concentration of Titania nanorods solution inhibiting the growth of microbial strain was found to be 5 microg/mL for all the tested pathogens. The photocatalytic activity of TiO2 nanorods showed better performance for dye degradation than commercially available P25. Moreover, Bio-TEM examination demonstrated that the exposure of the selected microbial strains to the Titania nanorods led to disruption of the cell membranes and leakage of the cytoplasm which cause bacteria to die eventually. Our results point the oxidative attack from exterior to the interior of the bacteria by hydroxyl radicals as the primary mechanism of photocatalytic inactivation.

Smart copper oxide nanocrystals: synthesis, characterization, electrochemical and potent antibacterial activity

We report herein the synthesis and characterization of novel CuO nanocrystals and their electrochemical and potent antibacterial activity. The utilized CuO nanocrystals were prepared by wet chemical method using copper acetate and hexamethylenetetramine (HMTA) as precursors. The physicochemical properties of the synthesized CuO nanocrystals having size ~6 nm were determined by X-ray diffractometer (XRD), energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM) and ultra violet-visible (UV-Vis) spectroscopy. The antibacterial study was carried out by minimum inhibitory concentration (MIC) using E. coli as model organism. The MIC of the CuO nanocrystals was found to be 2.5 μg/ml and the TEM analysis reveals that CuO nanocrystals caused disturbance to the cell wall which led to the irreversible damage to the cell envelope eventually leading to cell death. Furthermore, mechanism of bactericidal action of novel CuO nanocrystals is discussed in the light of our findings. Additionally, the synthesized CuO nanocrystals were applied as electrode material for supercapacitor. The specific capacitance of CuO nanocrystals measured at a potential scan rate of 5 mV/s was as high as 164.9 F g(-1).

Preparation, characterization, and cytotoxicity of CPT/Fe₂O₃-embedded PLGA ultrafine composite fibers: a synergistic approach to develop promising anticancer material

The aim of this study was to fabricate camptothecin/iron(III) oxide (CPT/Fe₂O₃)-loaded poly(D,L-lactide-co-glycolide) (PLGA) composite mats to modulate the CPT release and to improve the structural integrity and antitumor activity of the released drug. The CPT/Fe₂O₃-loaded PLGA ultrafine fibers were prepared for the first time by electrospinning a composite solution of CPT/Fe₂O₃ and neat PLGA (4 weight percent). The physicochemical characterization of the electrospun composite mat was carried out by scanning electron microscopy, energy dispersive X-ray spectroscopy, electron probe microanalysis, thermogravimetry, transmission electron microscopy, ultraviolet-visible spectroscopy, and X-ray diffraction pattern. The medicated composite fibers were evaluated for their cytotoxicity on C2C12 cells using Cell Counting Kit-8 assay (Sigma-Aldrich Corporation, St Louis, MO). The in vitro studies indicated a slow and prolonged release over a period of 96 hours with mild initial burst. Scanning electron microscopy, thermogravimetry, and X-ray diffraction studies confirmed the interaction of CPT/Fe₂O₃ with the PLGA matrix and showed that the crystallinity of CPT decreased after loading. Incorporation of CPT in the polymer media affected both the morphology and the size of the CPT/Fe₂O₃-loaded PLGA composite fibers. Electron probe microanalysis and energy dispersive X-ray spectroscopy results confirmed well-oriented composite ultrafine fibers with good incorporation of CPT/Fe₂O₃. The cytotoxicity results illustrate that the pristine PLGA did not exhibit noteworthy cytotoxicity; conversely, the CPT/Fe₂O₃ composite fibers inhibited C2C12 cells significantly. Thus, the current work demonstrates that the CPT/Fe₂O₃-loaded PLGA composite fibers represent a promising chemotherapeutic system for enhancing anticancer drug efficacy and selectively targeting cancer cells in order to treat diverse cancers.

Controlled synthesis of Mn₂O₃ nanowires by hydrothermal method and their bactericidal and cytotoxic impact: a promising future material

Mn₂O₃ nanowires with diameter ~70 nm were synthesized by a simple hydrothermal method using Mn(II) nitrate as precursor. X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy techniques were employed to study structural features and chemical composition of the synthesized nanowires. A biological evaluation of the antimicrobial activity and cytotoxicity of Mn₂O₃ nanowires was carried out using Escherichia coli and mouse myoblast C₂C₁₂ cells as model organism and cell lines, respectively. The antibacterial activity and the acting mechanism of Mn₂O₃ nanowires were investigated by using growth inhibition studies and analyzing the morphology of the bacterial cells following the treatment with nanowires. These results suggest that the pH is critical factor affecting the morphology and production of the Mn₂O₃ nanowires. Method developed in the present study provided optimum production of Mn₂O₃ nanowires at pH ~ 9. The Mn₂O₃ nanowires showed significant antibacterial activity against the E. coli strain, and the lowest concentration of Mn₂O₃ nanowires solution inhibiting the growth of E. coli was found to be 12.5 μg/ml. TEM analysis demonstrated that the exposure of the selected microbial strains to the nanowires led to disruption of the cell membranes and leakage of the internal contents. Furthermore, the cytotoxicity results showed that the inhibition of C₂C₁₂ increases with the increase in concentration of Mn₂O₃ nanowires. Our results for the first time highlight the cytotoxic and bactericidal potential of Mn₂O₃ nanowires which can be utilized for various biomedical applications.

Electrocatalytic behavior of calcium doped LaFeO3 as cathode material for solid oxide fuel cell

La(1-x)Ca(x)FeO3 (X = 0.0, 0.2, 0.4, abbreviated as LCF) as cathode material for intermediate temperature solid oxide fuel cells (IT-SOFC) was synthesized by new route of glycine nitrate method. LCF materials were characterized by X-ray diffraction (XRD), scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX), transmission electron microscopy (TEM), electrical and electrochemical impedance spectroscopy (EIS). The powder LCFs exhibited single phase with orthorhombic structure, highly porous and small nanoparticles with average size of 200-300 nm. The electrical conductivities of LCFs increased as increasing the Ca content and achieved the maximum electrical conductivity of 148 Scm(-1) for La0.6Ca0.4FeO3 (X = 0.4) at 550 degrees C. The improved conductivity of LCFs could be a promising cathode material for IT-SOFCs. In the impedance analysis of fabricated symmetry cell with the optimized La0.6Ca0.4FeO3 cathode and Ce0.8Sm0.2O3 (SDC) electrolyte, the minimum area specific resistance (ASR) of 0.15 omegacm2 was observed at 850 degrees C, which may due to the lowest activation energy (1.55 eV), resulting from the reduction of oxygen molecules into oxygen ions. It was found that calcium doping was essential to increase the charge carrier concentration of lanthanum iron oxide materials, resulting in the high conductivity at intermediate temperature.

Morphological and electrochemical properties of crystalline praseodymium oxide nanorods

Highly crystalline Pr6O11 nanorods were prepared by a simple precipitation method of triethylamine complex at 500°C. Synthesized Pr6O11 nanorods were uniformly grown with the diameter of 12-15 nm and the length of 100-150 nm without any impurities of unstable PrO2 phase. The Pr6O11 nanorod electrodes attained a high electrical conductivity of 0.954 Scm-1 with low activation energy of 0.594 eV at 850°C. The electrochemical impedance study showed that the resistance of electrode was significantly decreased at high temperature, which resulted from its high conductivity and low activation energy. The reduced impedance and high electrical conductivity of Pr6O11 nanorod electrodes are attributed to the reduction of grain boundaries and high space charge width.

Membrane saturated fatty acids and disease progression in multiple sclerosis patients

The risk of developing multiple sclerosis is associated with increased dietary intake of saturated fatty acids. We determined the fatty acid composition within the different phospholipid fractions of red blood and peripheral blood mononuclear cell membranes of 31 patients diagnosed with multiple sclerosis and 30 healthy control subjects using gas chromatography. Individual saturated fatty acids were correlated with the severity of neurological outcome as measured by the Kurtzke Expanded Disability Status Scale. Significant increases were found in multiple sclerosis peripheral blood mononuclear cell membrane sphingomyelin C14:0 and phosphatidylinositol C22:0. In the peripheral blood mononuclear cell membranes, C22:0 and C24:0 showed positive correlations, while C14:0, C16:0 and C20:0 showed inverse correlations with the Functional System Scores. In conclusion, this study is in accordance with previous studies that have shown an increase in shorter long-chain SATS in MS patients. In addition, this study also showed that higher C14:0 and C16:0 reflected better disease outcome as demonstrated by the inverse correlation with the EDSS and FSS. We have also characterized the specific SATS, that is, long-chain SATS that may increase the risk of developing MS.

Erythrocyte membrane fatty acids in patients with multiple sclerosis

Background

Reports on fatty acids levels in multiple sclerosis remain inconclusive.

Objective

To determine the erythrocyte membrane fatty acid levels in multiple sclerosis patients and correlate with Kurtzke Expanded Disability Status Scale.

Methods

Fatty acid composition of 31 multiple sclerosis and 30 control individuals were measured by gas chromatography.

Results

The membrane phosphatidylcholine C20:4 n – 6 concentration was lower in the multiple sclerosis patients when compared to that of the control group, P = 0.04 and it correlated inversely with the EDSS and FSS.

Conclusion

Decrease in C20:4 n – 6 in the erythrocyte membrane could be an indication of depleted plasma stores, and a reflection of disease severity.

Non-invasive diagnosis of H pylori infection: Evaluation of serological tests with and without current infection marker CIM

AIM: To evaluate the performance of commercially available immunochromatographic (ICT) and immunoblot tests covering the current infection marker CIM and conventional ELISA for the diagnosis of H pylori infection in adult dyspeptic patients.

METHODS: Consecutive non-treated dyspeptic patients undergoing diagnostic endoscopy were tested for H pylori infection by culture, rapid urease test, and histology of gastric biopsy specimens. Serum from 61 H pylori infected and 21 non-infected patients were tested for anti-H pylori IgG antibodies by commercial ELISA (AccuBind^TM ELISA, Monobind, USA), ICT (Assure^®H pylori Rapid Test, Genelabs Diagnostics, Singapore), and immunoblot (Helico Blot 2.1, Genelabs Diagnostics, Singapore) assays. ICT and immunoblot kits cover CIM among other parameters and their performance with and without CIM was evaluated separately.

RESULTS: Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of ELISA were 96.7%, 42.8%, 83.1%, 81.8%, and 82.9%, of ICT were 90.1%, 80.9%, 93.2%, 73.9%, and 87.8%, of ICT with CIM were 88.5%, 90.4%, 96.4%, 73.0%, and 89.0%, of immunoblot were 98.3%, 80.9%, 93.7%, 94.4%, and 93.9%, and of immunoblot with CIM were 98.3%, 90.4%, 96.7%, 95.0%, and 96.3%, respectively.

CONCLUSION: Immunoblot with CIM had the best performance. ICT with CIM was found to be more specific and accurate than the conventional ELISA and may be useful for non-invasive diagnosis of H pylori infection.

Prevalence of IgG antibody against measles, mumps and rubella in bangladeshi children: a pilot study to evaluate the need for integrated vaccination strategy

The present study was carried out to determine the seroprevalence of IgG antibodies in Bangladeshi children against measles (irrespective of vaccination status), mumps and rubella (MMR) to assess strategic need of combined vaccination for these diseases. A total of 456 children of 1 month to 15 years, were studied. Serum IgG antibodies against MMR were measured by enzyme-linked immunosorbent assay (ELISA). By 3 months, protective IgG antibody level (>40 AU for measles and mumps and >15 IU/ml for rubella) for the diseases found to be between 50% and 80% among the studied children. Protective measles antibody (IgG) was not detected in all the children of 3-9 months and significant number of children between 9 months and 5 years were unprotected (87-65%; P < 0.001). Moreover, children of 3-15 months had no protective antibody level against mumps and significant number of children between 15 months and 5 years were unprotected (92-71%; P < 0.001). Between 5 and 15 years of age, significant number of children became protective (63-85%, P < 0.001). Although, a majority of children between 3 months and 5 years had shown to have no protective antibody against rubella (89-71%; P < 0.01-0.001) between >10 and 15 years 71% children had protective level of antibodies (P < 0.001). No significant difference was observed in antibody prevalence regarding socioeconomic classes, nutritional status and parental education. The data showed that: (i) a significant number of children remain unprotected against MMR in childhood and (ii) an extensive nationwide survey is required to suggest an integrated vaccination strategy in order to implement appropriate control measures of the three infectious diseases.

Association of HLA class I antigen matching and early graft outcome in living donor kidney transplantation

INTRODUCTION

HLA antigen matching often plays an important role in organ transplantation. As for HLA class I antigen matching, there are differences of opinion regarding its influence on the outcome of renal transplantations. The aim of this study was to evaluate the association of HLA class I antigen matching with early graft outcomes in living donor kidney transplantation.

PATIENTS AND METHODS

We evaluated graft outcomes in the first month of transplantation. Major events were slow graft function (serum creatinine > 250 micromol/L at the end of first week), delayed graft function (patients requiring dialysis in first week), and acute rejection episode. Graft outcomes were compared for normal renal function (NRF, serum creatinine < or = 175 micromol/L) impaired renal function (IRF, serum creatinine > 175 micromol/L) or impaired graft function due to an acute rejection episode (IGF).

RESULTS

The 115 subjects had a mean age of 29 +/- 8 years and their donors 38 +/- 11 years (P < .01). Immunosuppression included prednisolone, azathioprine, and cyclosporine. Parents, siblings, and others were kidney donors in 46%, 33%, and 21%, respectively. Comparisons between NRF/IRF (serum creatinine 133 +/- 24 vs 201 +/- 36 micromol/L, P < .01) and NGF/IGF (serum creatinine 146 +/- 44 vs 161 +/- 39 micromol/L, P < .05) showed no difference in number or pattern of HLA matching.

CONCLUSION

HLA class I antigen matching may not produce an added influence on early graft outcome among living donor kidney transplantations.

Comparison between IS6110 and MPB64 primers for the diagnosis of Mycobacterium tuberculosis in Bangladesh by polymerase chain reaction (PCR)

The study was carried out to evaluate the efficacy of two different primers in PCR based diagnosis of tuberculosis on the basis of the time involvement, steps of PCR, cost and accuracy of results. Among 17 clinically suspected pulmonary tuberculosis patient's (M:F 65:35) sputum samples, 12 were found positive by both primers. Among 81 routine samples (sputum = 12; blood = 27; cerebrospinal fluid = 16; ascitic fluid = 12 and urine = 14), 12 were found to be positive by IS6110 primer while 13 were found positive by MPB64. The result of M. tuberculosis DNA PCR in sputum, ascitic fluid, CSF and urine samples were found to be similar in both the primers used. It is suggested that, M. tuberculosis DNA PCR in blood samples using MPB64 primers sometime gives false positive result and therefore, may not be recommended for blood samples. As in other samples both the primers gave almost the same result and therefore, both the primers can be used for MTB DNA PCR vice versa in order to cross check if one gives dubious result.

PCR can help early diagnosis of pulmonary tuberculosis

One hundred and fifty-one patients, clinically suspected for pulmonary tuberculosis (age: 31 +/- 13 years, male/female: 112/39), were investigated to evaluate the diagnostic potential of polymerase chain reaction (PCR) based detection of the Mycobacterium tuberculosis complex in sputum. The diagnostic efficacy of PCR was compared with culture of Mycobacterium tuberculosis on egg-based Lowenstein-Jensen modified medium. PCR detected 71.5% (108/151), whereas culture detected 66.2% (100/151) of the clinically suspected patients. There was a significant association between the results of PCR and culture (chi2 = 59.524, p < 0.001). However, 23.2% (35/151) samples were found negative in both culture and PCR. Considering culture as the gold standard, the sensitivity of the PCR was 92%. and its specificity 70%. This lower apparent specificity may be due to the higher sensitivity of PCR.

Chronic carriers of hepatitis B virus in Bangladesh: a comparative analysis of HBV-DNA, HBeAg/anti-HBe, and liver function tests

Serological markers of hepatitis B virus (HBV), liver function tests and quantitative estimation of HBV-DNA are important in the assessment of the state of infection and prognosis following treatment for hepatitis B. This study aimed to determine whether low-cost assays, eg hepatitis B e antigen (HBeAg) and liver function tests, could be used for the assessment of infectivity as an alternative to HBV-DNA estimation. We tested 125 hepatitis B carriers for HBeAg, antibody to HBeAg (anti-HBe), and serum HBV-DNA; we also carried out a range of standard liver function tests. Seventy-three subjects were positive and 52 were negative for HBeAg. Of the HBeAg positive cases, 3 were also positive for anti-HBe; of the HBeAg negative cases, 5 were also negative for anti-HBe. Of these 8 cases, 7 had no detectable HBV-DNA. Most of the HBeAg positive but anti-HBe negative subjects were positive for HBV-DNA (74.3%; 52/ 70) whereas most of the HBeAg negative and anti-HBe positive subjects (93.6%; 44/47) were also negative for HBV-DNA. Of 56 HBV-DNA positive individuals, alanine transaminase (ALT) was found to be raised in 69.6% (p=0.066) and aspartate transaminase (AST) was raised in 66.1% (p=0.011), while 67.9% had normal alkaline phosphatase (ALP) (p=0.054). HBeAg (p=0.018) and raised ALT (p=0.008) were found to be independent predictors for HBV-DNA positivity among HBV carriers. This study suggests that HBeAg positive and anti-HBe negative hepatitis B carriers with raised ALT and AST are likely to be positive for HBV-DNA; the combination of routine serology and biochemical tests may be considered as an alternative to HBV-DNA in evaluating the state of chronic HBV infection. However, HBV-DNA should be specifically assessed if discordance is observed between seromarkers and transaminases.

Predominance of the DEN-3 genotype during the recent dengue outbreak in Bangladesh

A recent outbreak of dengue in Bangladesh was marked by many fatal complications. As clinical virulence varies among the genotypes of dengue virus, a study was conducted to investigate the molecular genotypes of dengue in Bangladesh. Reverse transcription polymerase chain reaction was used to determine viral genotypes using oligonucleotide generic primers that produce a 511 bp product. The resulting product was typed by nested PCR with strain-specific primers, yielding 482 (DEN-1), 119 (DEN-2), 290 (DEN-3) and 392 (DEN-4), visualized on UV transilluminator after electrophoresis on 2% agarose gel stained with ethidium bromide. Of 45 clinically diagnosed dengue patients (mean age 28 years; male/female 30/15), 19 (42.2%) had detectable viral RNA in their blood. However, during the first 5 days of fever in 30 patients, the frequency was 60% (18/30), implying that the sooner serum is drawn after the fever, the greater the chances of detecting viral RNA. DEN-3 was detected in all except 2 patients who were infected with DEN-2. DEN-2 (two cases) and DEN-4 (one case) were present as co-infections with DEN-3. All of the patients presented with fever, anorexia and vomiting; many had headache and general body ache; a few had a rash. About a quarter had suffered episodes of bleeding, while ascites, pleural effusion and CNS symptoms were found in a few patients Patients positive for viral RNA were also positive for anti-dengue IgM (p=0.007) in subsequent sampling. The study suggests the predominance of DEN-3 infection with occasional co-infection with other types, during the recent outbreak of dengue in Bangladesh.

Prevalence of infectious diseases in Bangladeshi women living adjacent to a truck stand: HIV/STD/hepatitis/genital tract infections

BACKGROUND

Little is known about infection rates for human immunodeficiency virus (HIV) and other diseases that can be transmitted sexually in Bangladeshi women who may be at intermediate levels of risk--that is, women who are not commercial sex workers (CSWs) but whose sexual contacts may include men at high risk for STD. This study examines HIV/hepatitis/STD and other genital tract infections in women living near Tejgaon truck stand in Dhaka, Bangladesh.

METHODS

This population based study was conducted from January to December 1998. A random sample of 384 women provided urine and blood samples and participated in an interview; 261 of them also had a physical examination in which vaginal and cervical specimens were taken. Laboratory tests included PCR on urine and cervical swabs for gonorrhoea and chlamydia, culture for trichomoniasis, serology tests for syphilis, herpes simplex 2, hepatitis B, C, D, HIV1, HIV2, and clinical diagnoses of other genital tract infections.

RESULTS

None of the participants tested positive for HIV. In the 261 women who had a physical examination, trichomoniasis was detected in 19.5%, chlamydia in 3.4%, gonorrhoea in 5.4%, bacterial vaginosis in 37.2%, and candidiasis in 10%. In the full sample of 384 women, with tests of urine and blood, prevalence of infection with chlamydia, gonorrhoea, syphilis, and herpes simplex 2 was detected in 0%, 6.3%, 5.7%, and 32% respectively. Almost 50% of the subjects had ever been exposed to hepatitis B, 3.6% were currently infective, 1.6% had hepatitis C, and none had hepatitis D.

CONCLUSION

The high prevalence of certain of these infectious diseases indicates the need to implement prevention interventions with these women and, perhaps more importantly, with their male partners. Qualitative research is needed to provide insights into their sexual behaviour and the contexts in which high risk behaviours occur.