Source specific sedimentary response towards the differential anthropogenic impacts in terms of potentially toxic elements in an urban river

To investigate the interplay between varying anthropogenic activities and sediment dynamics in an urban river (Turag, Bangladesh), this study involved 37-sediment samples from 11 different sections of the river. Neutron activation analysis and atomic absorption spectrometry were utilized to quantify the concentrations of 14 metal(oid)s (Al, Ti, Co, Fe, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Zn). This study revealed significant toxic metal trends, with Principal coordinate analysis explaining 62.91 % of the variance from upstream to downstream. The largest RSDs for Zn(287 %), Mn(120 %), and Cd(323 %) implies an irregular regional distribution throughout the river. The UNMIX-model and PMF-model were utilized to identify potential sources of metal(oid)s in sediments. ∼63.65-66.7 % of metal(oid)s in sediments originated from anthropogenic sources, while remaining attributed to natural sources in both models. Strikingly, all measured metal(oid)s' concentrations surpassed the threshold effect level, with Zn and Ni exceeding probable effect levels when compared to SQGs.

The effect on income of providing near vision correction to workers in Bangladesh: The THRIVE (Tradespeople and Hand-workers Rural Initiative for a Vision-enhanced Economy) randomized controlled trial

INTRODUCTION

Presbyopia, the leading cause of vision impairment globally, is common during working years. However, no trials have assessed presbyopia's impact on income.

METHODS

In April 2017, we conducted a census among 59 Bangladesh villages to identify persons aged 35 to 65 years with presbyopia (presenting distance vision > = 6/12 bilaterally and correctable inability to see 6/13 at 40 cm with both eyes), who never had owned glasses. Participants were randomized (1:1) to receive immediate free reading glasses (intervention) or glasses delivered 8 months later (control). Visual demand of different jobs was stratified into three levels. Outcomes were between-group differences in the 8 month change in: self-reported monthly income (primary) and Near Vision Related Quality of Life (NVRQOL, secondary).

RESULTS

Among 10,884 census participants, 3,655 (33.6%) met vision criteria and 863 (23.6%) comprised a sample enriched for near vision-intensive jobs, but 39 (4.52%) could not be reached. All participants allocated to intervention (n = 423, 51.3%) and control (n = 401, 48.7%) received the appropriate intervention, and follow-up was available for 93.4% and 96.8% respectively. Groups were similar at baseline in all characteristics: mean age was 47 years, 50% were male, 35% literate, and about half engaged in "most near vision-intensive" occupations. Glasses wear at 8-month follow-up was 88.3% and 7.81% in intervention and control respectively. At baseline, both the intervention and control groups had a self-reported median monthly income of US$35.3. At endline, the median income for the intervention group was US$47.1 compared with US$35.3 for control, a difference of 33.4%. Predictors of greater income increase in multivariate models included intervention group allocation (OR 1.45, 95% CI 1.12, 1.88, P = 0.005), male sex (OR 2.41, 95% CI 1.84, 3.16, P <0.001), and not engaging in income-producing work at baseline (OR 2.35, 95% CI 1.69, 3.26, P<0.001).

CONCLUSION

Provision of reading glasses increases income in near vision-intensive occupations, and may facilitate return to work for those currently unemployed.

Heavy metals in popularly sold branded cigarettes in Bangladesh and associated health hazards from inhalation exposure

Tobacco products are widely recognized as a major contributor to death. Cigarette smoke contains several toxic chemicals including heavy metals particulate causing high health risks. However, limited information has been available on the health risks associated with the heavy metals in cigarettes commonly sold in the Bangladeshi market. This study evaluated the concentrations and potential health risks posed by ten concerned heavy metals in ten widely consumed cigarette brands in Bangladesh using an atomic absorption spectrometer. The concentration (mg/kg) ranges of heavy metals Pb, Cd, Cr, As, Co, Ni, Mn, Fe, Cu, and Zn vary between 0.46-1.05, 0.55-1.03, 0.80-1.2, 0.22-0.40, 0.46-0.78, 2.59-3.03, 436.8-762.7, 115.8-184.4, 146.6-217.7, and 34.0-42.7, respectively. We assume that the heavy metals content among cigarette brands is varied due to the differences in the source of tobacco they use for cigarette preparation. The carcinogenic risks posed by heavy metals follow the order of Cr > Co > Cd > As > Ni > Pb, while the non-carcinogenic risks for Cu, Zn, Fe, and Mn were greater than unity (HQ > 1), except for Fe. The existence of toxic heavy metals in cigarette tobacco may thus introduce noticeable non-carcinogenic and carcinogenic health impacts accompanying inhalation exposure. This study provides the first comprehensive report so far on heavy metal concentration and associated health risks in branded cigarettes commonly sold in Bangladesh. Hence, this data and the information provided can serve as a baseline as well as a reference for future research and have potential implications for policy and legislation in Bangladesh.

Re-evaluation and a Structure-Activity Relationship Study for the Selective Anti-anaerobic Bacterial Activity of Luminamicin toward Target Identification

Luminamicin (1) isolated in 1985, is a macrodiolide compound exhibiting selective antibacterial activity against anaerobes. However, the antibacterial activity of 1 was not fully examined. In this research, re-evaluation of the antibacterial activity of 1 revealed that 1 is a narrow spectrum and potent antibiotic againstClostridioides difficile(C. difficile) and effective against fidaxomicin resistantC. difficilestrain. This prompted us to obtain luminamicin resistantC. difficilestrains for the determination of the molecular target of 1 inC. difficile. Sequence analysis of 1-resistantC. difficileindicated that the mode of action of 1 differs from that of fidaxomicin. This is because no mutation was observed in RNA polymerase and mutations were observed in a hypothetical protein and cell wall protein. Furthermore, we synthesized derivatives from 1 to study the structure-activity relationship. This research indicated that the maleic anhydride and the enol ether moieties seem to be pivotal functional groups to maintain the antibacterial activity againstC. difficileand the 14-membered lactone may contribute to taking an appropriate molecular conformation.

Rediscovery of Tetronomycin as a Broad-Spectrum and Potent Antibiotic against Drug-Resistant Gram-Positive Bacteria

Tetronomycin (1), first isolated from a cultured broth of Streptomyces sp. by Juslen et al. in 1974, is a polycyclic polyether compound. However, the biological activity of 1 has not been thoroughly examined. In this study, we found that 1 exhibits more potent antibacterial activity than two well-known antibacterial drugs (vancomycin and linezolid) and is effective against several drug-resistant clinical isolates including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci. Furthermore, we reassigned the ¹³C NMR spectra of 1 and performed a preliminary structure-activity relationship study of 1 to synthesize a chemical probe for target identification, which implied different targets based on its ionophore activity.

A Combination Strategy of Multidrug-Sensitive Budding Yeast and Chemical Modifications Enabling to Find a New Overlooked Antifungal Compound, Sakurafusariene, from In-House Fractionated Library

In this report, we disclose our discovery of a new antifungal natural product, sakurafusariene (1), from an in-house fractionated library of the culture broth of Fusarium sp. FKI-7550 strain by using a combination strategy of multidrug-sensitive yeast and chemical modification. Throughout our investigation, we encountered challenges in the isolation of natural product 1. A chemical modification strategy via alkylation of 1 allowed for removal of the impurities enabling us to elucidate the structure of 1. Furthermore, we synthesized ester derivatives using a method inspired by the isolation study of 1, which gave us valuable information to understand a preliminary structure-activity relationship against Pyricularia oryzae growth inhibitory activity.

ODP604 | LBSUN287 Ketosis-prone Type 2 Diabetes (Flatbush Diabetes) In Remission: Report Of Two Cases

 

Diabetic ketoacidosis (DKA) is a triad of uncontrolled hyperglycemia, metabolic acidosis, and increased total body ketone concentration1. Diabetic ketoacidosis (DKA) is a well-known manifestation of Type 1 diabetes2; however, there has been an increase in the incidence of DKA as the first presentation in Type 2 diabetes. This subtype of diabetes is typically seen in non-Caucasian middle-aged obese males due to non-autoimmune disruption of glucose metabolism, which requires an initial intensive insulin regimen. After initial insulin treatment for several weeks to several months, a significant percentage of people can become insulin independent with an oral hypoglycemic agent(OHA) and /or just lifestyle modification, and in remission for many years3. This hybrid form of diabetes sharing the characteristics of T1DM and T2DM is called "Flatbush diabetes", also known as "ketosis-prone T2DM4 5. This article aims to emphasize the importance of early recognition of this heterogeneous syndrome through the two representative case reports of Ketosis-prone T2DM.

Case presentation

We describe two cases of African American men (elderly and young adult) with no past medical histories, who presented to the Emergency Department with a few days history of polyphagia, polydipsia, polyuria and fatigue. New onset of Type 2 diabetes and unprovoked DKA were diagnosed. Both of them received standard treatment with intravenous fluid and insulin drip, recovered uneventfully and discharged with insulin. Both of them followed up closely in our endocrinology clinic, their GAD antibodies were 0. 00(n<=0. 02nmol/L), Islet cell antibody<1: 4(n<1: 4) and C-peptide were 2.6ng/mL and 6ng/mL(1.1-4.4ng/mL) respectively. Their insulin was gradually withdrawn with the addition of an oral hypoglycemic agent. Both the patients are currently insulin independent for more than 15 months.

Conclusion

This is an important clinical entity to recognize ketosis-prone T2DM as insulin independence positively impacts quality of life and decreases economic burden on the health care system. For patients with suspected ketosis-prone T2DM, B-cell autoantibodies and C-peptide level should be obtained 1-3 weeks at the first outpatient visit, as it can predict patients’ prognosis. These patients should also be referred to an endocrinologist and need careful follow-up. Among all ketosis-prone T2DM patients, those with preserved B-cell function are more likely to be insulin independent and go into remission phase.

Presentation: Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.

LBODP105 A Case of Significantly Increased Levothyroxine Requirement With Rifampin Therapy

Introduction

Rifampin has a wide range of drug interactions through increased hepatic microsomal enzyme activity. We are reporting a case of a patient with post-surgical hypothyroidism on stable thyroid hormone replacement therapy who required significantly higher doses of levothyroxine after starting rifampin.

Case Report

Patient is a 78-year-old woman with history of Papillary Thyroid Cancer (PTC) in remission status post thyroidectomy in 1994 and radioactive iodine therapy in 1997. Patient had been on a stable dose of Levothyroxine of 75-88mcg daily until a visit in January 2013 when her TSH was found to be 39 despite compliance with levothyroxine. Further history revealed that she was diagnosed with Mycobacterium Avium Intracellulare (MAI) infection of the lungs for which she was given rifampin therapy. Her Levothyroxine dose was progressively increased to 150mcg daily. She received rifampin therapy for 18 months, from August 2012 until April 2013. Her Levothyroxine dose was later changed to average 139 mcg /day based on TSH levels and continued to be the same through the rifampin course. In April 2014, and following discontinuation of rifampin, Levothyroxine was decreased to 100mcg daily and subsequently 75mcg daily. During a relapse of MAI in March 2016, her levothyroxine dosage was similarly again increased to 125mcg daily for TSH of 24.58. In June 2017, rifampin was discontinued after completion of second course of MAI treatment, and Levothyroxine dose decreased to 88 mcg daily, and subsequently 75 mcg in September 2017, and average daily 64mcg most recently given age and long-term remission with target mid normal TSH.

Discussion

Rifampin is used to treat active tuberculosis and MAI infection among other uses. It is a hepatic enzyme inducer which significantly interacts with other drugs. It has been reported previously to cause hypothyroidism in patients with underlying thyroid disorder and increased serum TSH while on levothyroxine, but its impact range on thyroid function has not been clearly described. Our patient was on stable levothyroxine dose following thyroidectomy, and required almost a 100% increase of levothyroxine dose when started on rifampin therapy, returning to baseline levothyroxine requirements off rifampin. This case highlights the severe hypothyroidism and significant impact on levothyroxine dose requirements following rifampin therapy, and the importance of close thyroid function monitoring in patients with hypothyroidism and on rifampin, especially in context of post-surgical hypothyroidism.

Presentation: No date and time listed

Ketosis-Prone Type 2 Diabetes (Flatbush Diabetes) in Remission: A Report of Two Cases

Diabetic ketoacidosis (DKA) is a triad of uncontrolled hyperglycemia, metabolic acidosis, and increased total body ketone concentration. It is a well-known manifestation of type 1 diabetes mellitus (T1DM). However, it can also be the first presentation of type 2 diabetes mellitus (T2DM). This subtype of diabetes shares the characteristics of both T1DM and T2DM and is called 'Flatbush diabetes,' also known as 'ketosis-prone T2DM.' This article highlights the importance of early identification of ketosis-prone T2DM (KPD). We describe two cases of African American men with no past medical histories who presented with unproved DKA as the first presentation of T2DM requiring initial intensive insulin therapy, which was gradually withdrawn with the addition of metformin. Both patients are currently insulin independent for more than 15 months. It is an essential clinical entity to recognize as insulin independence positively impacts the quality of life and decreases the economic burden on the health care system. 

Insights into the structure-activity relationship of a type III secretion system inhibitor, aurodox

Aurodox was originally isolated in 1972 as a linear polyketide compound exhibiting antibacterial activity against Gram-positive bacteria. We have since identified aurodox as a specific inhibitor of the bacterial type III secretion system (T3SS) using our original screening system for inhibition of T3SS-mediated hemolysis in enteropathogenic Escherichia coli (EPEC). In this research, we synthesized 15 derivatives of aurodox and evaluated EPEC T3SS inhibitory activity as well as antibacterial activity against EPEC. One of the derivatives was highly selective for T3SS inhibition, equivalent to that of aurodox, but without exhibiting antibacterial activity (69-fold selectivity). This work revealed the structure-activity relationship for the inhibition of T3SS by aurodox and suggests that the target of T3SS is distinct from the target for antibacterial activity.

Confluenine G, a new compound from a basidiomycetous yeast Moesziomyces sp. FKI-9540 derived from the gut of a moth Acherontia lachesis (Lepidoptera, Sphingidae)

Most natural products derived from microorganisms have been sought from actinomycetes and filamentous fungi. As an attempt to develop new microbial resources in the exploratory research for natural products, we searched for new compounds from unexploited microbial taxa presumed to have biosynthetic gene clusters. A new compound confluenine G (1) and a known compound (2Z)-2-octyl-2-pentenedioic acid (2) were isolated from a cultured broth of basidiomycetous yeast, Moesziomyces sp. FKI-9540, derived from the gut of a moth Acherontia lachesis (Lepidoptera, Sphingidae). Based on the results of HR-ESI-MS and NMR analyses, the planar structure of 1 was elucidated. Confluenine G (1) was a new analog of nitrogen-oxidized isoleucine and had rare substructures with oxime and hydroxamic acid in molecule.

Fermentation optimization of cellulase production from sugarcane bagasse by Bacillus pseudomycoides and molecular modeling study of cellulase

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Isolation of cellulase producing Bacillus pseudomycoides from sugarcane bagasse.

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Fermentation and optimization of different parameters for cellulase production.

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Modeling and validation of cellulase enzyme.

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Interaction dynamics between cellulase and cellulose.

Degradation of cellulosic carbon, the most important natural carbon reservoirs on this planet by cellulase is very essential for valuable soluble sugars. This cellulase has potential biotechnological applications in many industrial sectors. Thus the demand of cellulase is increasing more frequently than ever. Agro industrial byproducts and suitable microbes are of an important source for the production of cellulase. Bacillus pseudomycoides and sugarcane bagasse were used for the production of cellulase and different process parameters influencing the production of cellulase were optimized here. The bacterium showed maximum cellulase production in the presence of sugarcane bagasse, peptone and magnesium sulfate at pH 7, 40 °C in 72 h of incubation. Primary structures of the cellulase is consists of 400 amino acid residues having molecular weight 44,790 Dalton and the theoretical PI is 9.11. Physiochemical properties of cellulase indicated that the protein has instability index 25.77. Seven hydrogen bonds were observed at multiple sites of the cellulase enzyme; His269, Asp237, Asn235, Tyr271, Ser272, Gln309, Asn233. This protein structure may play first hand in further development of exploring cellulase and cellulose interaction dynamics in Bacillus sp. Thus this bacterium may be useful in various industrial applications owing to its cellulase producing capability.

Patients with Clostridium difficile infection and prior appendectomy may be prone to worse outcomes

BACKGROUND

Clostridium difficile infection (CDI) occurs due to a dysbiosis in the colon. The appendix is considered a ‘safe house’ for gut microbiota and may help repopulate gut flora of patients with CDI.

AIM

To study the impact of prior appendectomy on the severity and outcomes of CDI.

METHODS

We retrospectively reviewed data of 1580 patients with CDI, admitted to our hospital between 2008 to 2018. Patients were grouped based on the presence or absence of the appendix. The primary aim was to (1) assess all-cause mortality and (2) the severity of CDI. Severity was defined as per the Infectious Diseases Society of America criteria. Logistic regression, and propensity score analysis using inverse probability of treatment weights (IPTW) was performed.

RESULTS

Of the 1580 patients, 12.5% had a history of appendectomy. There was no statistical difference in mortality between patients with a prior appendectomy or without (13.7% vs 14%, P = 0.877). However, a history of appendectomy affected the severity of CDI [odds ratio (OR) = 1.32, 95% confidence interval: 1.01-1.75]. On IPTW, this association remained significant (OR = 1.59, P < 0.05). On multivariable analysis of secondary outcomes, prior appendectomy was also associated with toxic megacolon (OR = 5.37, P < 0.05) and colectomy (OR = 2.77, P < 0.05).

CONCLUSION

Prior appendectomy may affect the severity of CDI, development of toxic megacolon and the eventual need for colectomy. Since treatment of CDI is governed by its severity, stronger antibiotic regimens or earlier use of fecal microbiota transplant may be a viable option for patients with prior appendectomy.

Denosumab Induced Severe Hypocalcemia in a Patient With Metastatic Prostate Cancer

Background: Denosumab can lead to severe hypocalcemia in patients with underlying risk factors such as vitamin D deficiency, low PTH, hypomagnesemia, and CKD. Denosumab is a monoclonal antibody against RANKL, reducing the activity of osteoclasts and thus reducing the release of calcium in the bloodstream causing hypocalcemia. Hypocalcemia can range from mild to severe symptoms requiring prolonged hospitalization. Medications such as zoledronic acid and Denosumab are known to reduce the occurrence of Skeletal related events (pathological fracture, spinal cord compression, and radiation to bone). For metastatic prostate cancer, about 90% can develop bone metastasis with significant morbidity and mortality [1]. Our patient presented with severe hypocalcemia after denosumab use without any above risk factors. Clinical Case: A 66-year-old male with a medical history of Prostate cancer with Metastasis to chest and bone presented to ER with syncope. Patient-reported poor oral intake, nausea, and vomiting for the last few days. In the ER, the patient was found afebrile, bp 116/76, HR 92, saturating 100% on room air. On examination, the patient was found lethargic, malnourished, foley in place due to chronic urinary retention. The abdomen was soft and non-tender. Laboratory findings were significant for Hb 9.1, Na 133, K3.6, bicarb 21, total calcium (Ca) 4.2, ionized Ca 0.63 and corrected Ca 5.4, magnesium 1.6, phosphorus 2.1, albumin 3.3, ALT 218, AST 229, ALP 1607. Lipase 82, Total bilirubin 1.5, direct bilirubin 0.8. Spot Urinary Ca 0.7, Vitamin D 25 OH 36.9, serum PTH 225 pg/mL. Serum cortisol AM 20.9, BUN 16, and serum Creatinine 1.0. The patient was started on 11g calcium gluconate in 1L dextrose @ 50c/hr and calcitriol 0.25mcg twice daily. Serum Ca level was monitored every 6 hours and reached 6.7. Later was started on Ca carbonate 1250 TID with meals. Finally, after electrolyte correction, the patient clinically improved and was discharged with the plan to follow Calcium at the outpatient clinic. On review of previous labs at the oncology clinic, the patient received Denosumab at his oncologist’s clinic 10 days before this hospital admission, last Ca level from 6 months ago 8.6, the patient was not any vitamin D or Ca supplement. Conclusion: Many case reports have been published on severe hypocalcemia after denosumab usage. Several patients had underlying risk factors such as vitamin D deficiency, osteoblastic lesion, and AKI leading to an additional cause of hypocalcemia. We emphasize careful monitoring of serum Ca levels particularly in the first few weeks of treatment even without significant risk factors for hypocalcemia. References: [1] Metastatic patterns of prostate cancer: an autopsy study of 1,589 patients. Bubendorf L, Schöpfer A, Wagner U, Sauter G, Moch H, Willi N, Gasser TC, Mihatsch MJ. . Hum Pathol. 2000 May; 31(5):578–83

Heavy metal contamination and ecological risk assessment in water and sediments of the Halda river, Bangladesh: A natural fish breeding ground

This study reports the mass fractions of Al, Cr, Mn, Fe, Co, Zn, As, Ni, Cu, Cd, Hg, and Pb in water and sediments of the Halda river, Bangladesh, and studies the distribution, contamination, and potential ecological risks of the metals and metalloid. The average mass fractions of As, Cd, and Pb are relatively higher in sediments compared to those in background values, whereas Al, Fe, Mn, and Pb concentration fractions in water are higher than the international guideline values. The results of the different contamination indices indicate that Halda river sediments are minorly contaminated by As and Pb and moderately to considerably contaminated by Cd. The ecological risk assessments indicate considerable to high ecological risk due to Cd. Multivariate statistical analysis reveals the origin of the contaminants in the river, and indicate that Cr, Zn, Pb, and Cd are from anthropogenic activities while the other metals originate from natural lithogenic actions.

Promoting and maintaining urinary continence: Follow-up from a cluster-randomized trial of elderly village women in Bangladesh

AIMS

Pelvic floor and mobility exercises were shown to be effective in managing incontinence in a cluster-randomized trial (CRT) of village women aged 60 to 75 years in Bangladesh. The present analysis examines continence 12 months after the CRT and exercise program implementation with village paramedics as preceptors.

METHODS

Women from nine villages in the exercise arm of the CRT were followed-up 12 months after the 6-month intervention. They provided information about exercise since the CRT and a 3-day continence record (3DCR). Posttrial, a further 6-month exercise intervention led by village paramedics was initiated in 20 villages. Women completed the two-item Sandvik severity questionnaire before and after the intervention. Paramedics kept a record of each woman's attendance at the 48 exercise sessions RESULTS: A total of 130 of 150 women from the CRT completed the 12-month follow-up; 61.5% were dry on the 3DCR at follow-up. Total continence was related to the continuation of exercises carried out in the home and absence of urinary tract infection at follow-up. Those exercising at follow-up had an odds ratio (OR) of 3.49 (95% confidence interval [CI], 1.86-6.58) of being continent at follow-up. Higher end-of-CRT body mass index was associated with greater follow-up leakage. In the 20-village roll-out, with 316 incontinent women, improvement in both severity and total continence on the Sandvik questionnaire were related to a total number of sessions attended (OR = 1.09; 95% CI, 1.05-1.13). At roll-out, 38.6% achieved continence, comparable to 43.0% in the CRT using physiotherapy preceptors CONCLUSIONS: Group exercise classes led by paramedics resulted in a marked improvement in continence but maintenance requires exercise postintervention.

Effects of Different Sources of Nitrogen on Endophytic Colonization of Rice Plants by Azospirillum sp. B510

Azospirillum sp. B510, a free-living nitrogen-fixing bacterium isolated from the stems of rice (Oryza sativa cv. Nipponbare), was investigated to establish effective conditions for the colonization of rice plants. We analyzed the effects of the nitrogen sources KNO₃, NH₄Cl, urea (CO[NH₂]₂), and NH₄NO₃ at different concentrations (0.01–10 mM) on this colonization. Nitrogen promoted plant growth in a concentration-dependent manner, with minor differences being observed among the different nitrogen sources. Bacterial colonization was markedly suppressed on media containing NH₄⁺ concentrations higher than 1 mM. Since concentrations of up to and including 10 mM NH₄⁺ did not exhibit any antibacterial activity, we analyzed several factors affecting the NH₄⁺-dependent inhibition of endophytic colonization, including the accumulation of the reactive oxygen species H₂O₂ and the secretion of the chemotactic substrate malic acid. The accumulation of H₂O₂ was increased in rice roots grown on 1 mM NH₄Cl. The amounts of malic acid secreted from NH₄-grown rice plants were lower than those secreted from plants grown without nitrogen or with KNO₃. Although the bacterium exhibited chemotactic activity, moving towards root exudates from plants grown without nitrogen and KNO₃-grown plants, this activity was not observed with root exudates from NH₄⁺-grown plants. NH₄⁺, but not NO₃⁻, caused the acidification of growth media, which inhibited plant bacterial colonization. These NH₄⁺-dependent phenomena were markedly suppressed by the stabilization of medium pH using a buffer. These results demonstrate that the type and concentration of nitrogen fertilizer affects the colonization of rice plants by Azospirillum sp. B510.

Assessment of rare earth elements, Th and U profile of a site for a potential coal based power plant by instrumental neutron activation analysis

To study the compositional trends of rare earth elements (REEs: La, Ce, Nd, Sm, Eu, Tb, Dy, Yb, Lu), Th and U in soil samples collected from a site for a potential coal based power plant as well as to conduct a preliminary assessment of environmental impact of the proposed power plant in terms of REEs, Th and U, we have analyzed nine soil samples by instrumental neutron activation analysis. Evaluation of data quality by repeated analysis of IAEA-Soil-7 and IAEA-SL-1 ensures a proper data base-line for the REEs, Th and U abundances of the sampling site. Chondrite-normalized abundance patterns demonstrate the heavy REEs–light rare earth elements and Th–U fractionations in our sample suite along with significant negative Eu anomaly. Thorium/U ratio in our study area ranges from 4.55 to 6.07 which is higher than that of upper continental crust. Preliminary assessment of environmental impact of the proposed power plant is evaluated by taking NIST-SRM-1633b (coal-fly-ash) as contaminant as coal-fly-ash will be the major byproduct of the power plant. Previous literature studies and our prevailing data invoke that proposed power plant will have no severe impact on soil originated biota and on human health in terms of REEs, Th and U abundances. However, the long term effect of excessive REEs, Th and U as well as the other elemental abundances originating from coal-fly-ash should also be taken into an account.

Contamination and ecological risk assessment of trace elements in sediments of the rivers of Sundarban mangrove forest, Bangladesh

In this study, total concentrations of 16 trace elements (Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, Sb, Hg, Pb, Th and U) in sediments of the rivers of the Sundarban mangrove forest, after the catastrophic oil spill accident in the Sela river of Sundarban, were determined. The overall mean concentrations of V, Cr, Fe and Cd in surface sediments of the Sundarban are remarkably higher than available literature data of those elements. Trace element contamination assessment, using different environmental contamination indices, reveals that As, Sb, Th and U are low to moderately contaminated while Cd is moderately to severely contaminated in the sediments of this area. The multivariate statistical analyses were applied to reveal the origin and behavior of the elements during their transport in the mangrove ecosystem. High Cr, Ni, Cu and As concentrations suggest the risk of potentially adverse biological effects in the ecosystem.

Association between Helicobacter Pylori and Hyperemesis Gravidarum

Background: Hyperemesis gravidarum (HG) is the severe form of the nausea & vomiting in pregnancy and is associated with weight loss, ketonemia ,ketonuria ,electrolyte imbalances and profound volume depletion. Increased accumulation of fluid caused by elevated steroid hormones in pregnancy, a shift in pH and change of pH in the gastrointestinal tract could result in the manifestation of subclinical Helicobacter pylori (H. Pylori) infection. We therefore examined whether seropositivity for IgG antibodies to H. Pylori may be related to hyperemesis graviderum.Objective: To determine the association of H-pylori infection in hyperemesis graviderum patients.Methodology: A cross sectional study was conducted in the department of obstetrics and gynaecology, Dhaka medical college hospital from January 2007 to December 2008. Total 82 pregnant patients, 40 were hyperemesis gravidarum patients (Cases, group A) and 42 were normal pregnancy without hyperemesis graviderum (Control, group B) for admission and attending for routine ANC in OPD were selected. Purposive sampling method was followed as per inclusion and exclusion criteria. Evaluation of the patients was based on history, physical examination and investigation. Serum IgG antibody response to H.pylori antigen by ELISA were measured from every patients and analysed for its association with HG.Results: Most of the patients of this study were primi gravida, Group-A was 72.5% and Group-B was 66.7%. Maximum number of women in both the groups belonged to lower socio-economic status (Group-A was 85% and Group-B was (76%). Previous H/O hyperemesis gravidarum in the Group-A was 52.5% and Group-B was 07 % (p<.01), that is statistically highly significant. Antibody to Helicobactor pylori in serum was positive in Group-A 47.5%, and Group-B 19%. The difference was statistically significant. (p value-0.006).Conclusion: According to the findings of our study, H.pylori infection would seem to be an important associated factor in the exacerbation of HG, but it does not seem to be the only cause of the disease.J Shaheed Suhrawardy Med Coll, June 2016, Vol.8(1); 13-16

Evaluation of Chromogenic Medium for Selective Isolation of Yersinia

Cefsulodin-irgasan-novobiocin agar (CIN) has been used as a selective agar to detect Yersinia in food or human patients; however, its components can inhibit the growth of some strains of Yersinia enterocolitica serovar O3 and Y. pseudotuberculosis. Recently, a new Yersinia selective agar, CHROMagar Yersinia enterocolitica (CAYe), was developed and evaluated as a novel selective agar for pathogenic Y. enterocolitica. In this research, a total of 251Yersinia strains (176 pathogenic Y. enterocolitica, 59 Y. pseudotuberculosis, and 16 non-pathogenic Yersinia) were cultured on both CIN and CAYe for comparison. Except for 10 of 104 pathogenic Y. enterocolitica O3 strains and 59 Y. pseudotuberculosis strains, 198 Yersinia isolates grew on both media after 48 hr of incubation at 32℃. Of the 10 pathogenic Y. enterocolitica O3 which could not grow on CIN or CAYe, 9 strains could not grow on CIN with supplements and 1 strain could not grow CAYe with supplements. Of 9 strains which did not grow on CIN with supplements, 3 strains could not grow on CIN without supplements. However, 1 strain which did not grow on CAYe with supplements could grow on CAYe without supplements. All of the Y. pseudotuberculosis strains could grow on CIN with/without supplements and on CAYe without supplements. The results indicate that the inhibition of the growth of Y. enterocolitica O3 on CIN is related to the components of CIN; however, the inhibition on CAYe appears to be related to the supplements in CAYe. Therefore, CAYe may be a more useful selective medium than CIN for pathogenic Y. enterocolitica .

Elemental distribution of metals in urban river sediments near an industrial effluent source

To study the compositional trends associated with the spatial and layer wise distribution of heavy metals as well as the sediment response towards the untreated chemical wastes, we have analyzed river (Buriganga, Bangladesh) sediments by instrumental neutron activation analysis (INAA) and energy dispersive X-ray fluorescence (EDXRF). In nine sediment samples 27 elements were determined where Na, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Zn, As, Rb, Cs, La, Ce, Sm, Dy, Hf, Th and U were determined by INAA and Cu, Sr, Ba, Hg and Pb were determined by EDXRF. Pollution level and the origin of pollutants were evaluated by the aid of geo-accumulation index (Igeo), enrichment factor (EF), pollution load index (PLI) and the inter-element correlation analysis. Major elements are somehow buffered even though the pollution level is severe while the trace metals seem to be highly responsive. Among the heavy metals, Cr is the dominant pollutant, though the pollution level varies systematically with the sampling depth and the distance from the contamination source. Positive linear correlation between Cr and Zn (0.94) ensures the similar anthropogenic source(s) for these two metals, but the sediments of this study respond differently depending upon their geochemical behavior. Rare earth elements (here La, Ce, Sm and Dy), Th and U seem to have crustal origin and the Th/U ratio varies from 2.58 to 4.96.

Experimental cross section for the 152Sm(n, γ)153Sm reaction at 0.0334 eV

The neutron capture cross section for the 152Sm(n,  γ)153Sm reaction at an energy of 0.0334 eV was measured for the first time using monochromatic neutrons of a powder diffractometer at the TRIGA Mark II nuclear reactor at Dhaka, Bangladesh. The 197Au(n,  γ)198Au reaction was used to monitor the neutron beam intensity. The radioactivity of the products was determined via high resolution γ-ray spectrometry. The obtained cross section value is 184 ± 22 b, which is consistent with both the ENDF/B-VII and TENDL-2012 data libraries. The measured value at 0.0334 eV and the previous data at 0.0536 eV confirm the reliability of the data in the above libraries.

Maternal serum zinc level and its relation with neonatal birth weight

The present study was conducted in the Department of Obstetrics & Gynaecology, Mymensingh Medical College Hospital, Mymensingh and Molecular Microbiology & Central Laboratory of Bangladesh Institute of Nuclear Agriculture (BINA) from 15th November 2007 to 31st May 2009 to find out the relation between maternal serum zinc level with neonatal birth weight. Hundred pregnant women who were advised to take 61.8 mg zinc daily throughout pregnancy were assigned to study group while the pregnant woman did not take zinc orally were allocated into control group. Serum zinc levels were measured between 37-42 weeks gestation and birth weight were measured just after delivery. Data were processed and analyzed using SPSS version 11.5. The test used to analyze the data was descriptive statistics, Chi-square probability test, Pearson correlation, unpaired t-test and odds ratio. A probability value of <0.05 was considered significant. Majority (97%) of the cases who received zinc during their antenatal period had normal serum zinc (≥ 700μg/L) level compared to only 22% of the control group woman who did not receive zinc. Normal birth weight of babies in pregnant woman who received zinc is 5.7 times higher than the pregnant woman who did not receive zinc. As the present study was a cross-sectional one, further study with large sample size and prospective design is recommended.