Mohammad Shahidul Islam

Impact of 4.0% chlorhexidine cord cleansing on the bacteriologic profile of the newborn umbilical stump in rural Sylhet District, Bangladesh: a community-based, cluster-randomized trial.

Background: Randomized trials from South Asia indicate umbilical cord chlorhexidine cleansing reduces mortality and omphalitis. No community-based data are available on bacteriological profile of the cord, early neonatal colonization dynamics, or impact of cord cleansing on colonizing organisms. Such data could clarify the design of scaled chlorhexidine interventions. Methods: Umbilical swabs were collected at home (days 1, 3, 6) after birth from infants participating in a trial of 3 cord-care regimens (no chlorhexidine, single cleansing, multiple cleansing) in Sylhet, Bangladesh. Overall and organism-specific positivity rates were estimated by cord-care regimen and by day of collection. Results: Between September 2008 and October 2009, 1923 infants contributed 5234 umbilical swabs. Positivity rate was high (4057 of 5234, 77.5%) and varied substantially across groups. Immediate (day 1) reductions in cord colonization were observed in single- (prevalence rate ratio = 0.75, 95% confidence interval: 0.70–0.81) and multiple- (prevalence rate ratio = 0.71, 95% confidence interval: 0.66–0.77) cleansing groups. Reductions persisted and increased in magnitude through day 6 only if babies received multiple applications. On days 1, 3, and 6, respectively, multiple cleansing consistently reduced invasive organisms such as Escherichia coli (49%, 64%, and 42% lower), Klebsiella pneumoniae (46%, 53%, and 33% lower), and Staphylococcus aureus (34%, 84%, and 85% lower). Conclusions: Cord cleansing with 4.0% chlorhexidine immediately after birth reduces overall and organism-specific colonization of the stump. Reductions are greater and sustained longer with daily cleansing through the first week of life, suggesting that programs promoting chlorhexidine cleansing should favor multiple over single applications.

Synthesis, in vitro biological activities and in silico study of dihydropyrimidines derivatives

We describe here the synthesis of dihydropyrimidines derivatives 3a-p, and evaluation of their α-glucosidase enzyme inhibition activities. Compounds 3b (IC50=62.4±1.5 μM), 3c (IC50=25.3±1.26 μM), 3d (IC50=12.4±0.15 μM), 3e (IC50=22.9±0.25 μM), 3g (IC50=23.8±0.17 μM), 3h (IC50=163.3±5.1 μM), 3i (IC50=30.6±0.6 μM), 3m (IC50=26.4±0.34 μM), and 3o (IC50=136.1±6.63 μM) were found to be potent α-glucosidase inhibitors in comparison to the standard drug acarbose (IC50=840±1.73 μM). The compounds were also evaluated for their in vitro cytotoxic activity against PC-3, HeLa, and MCF-3 cancer cell lines, and 3T3 mouse fibroblast cell line. All compounds were found to be non cytotoxic, except compounds 3f and 3m (IC50=17.79±0.66-20.44±0.30 μM), which showed a weak cytotoxic activity against the HeLa, and 3T3 cell lines. In molecular docking simulation study, all the compounds were docked into the active site of the predicted homology model of α-glucosidase enzyme. From the docking result, it was observed that most of the synthesized compounds showed interaction through carbonyl oxygen atom and polar phenyl ring with active site residues of the enzyme.

Infection Surveillance Protocol for a Multicountry Population-based Study in South Asia to Determine the Incidence Etiology and Risk Factors for Infections Among Young Infants of 0 to 59 Days Old.

Background: Insufficient knowledge of the etiology and risk factors for community-acquired neonatal infection in low-income countries is a barrier to designing appropriate intervention strategies for these settings to reduce the burden and treatment of young infant infection. To address these gaps, we are conducting the Aetiology of Neonatal Infection in South Asia (ANISA) study among young infants in Bangladesh, India and Pakistan. The objectives of ANISA are to establish a comprehensive surveillance system for registering newborns in study catchment areas and collecting data on bacterial and viral etiology and associated risk factors for infections among young infants aged 0–59 days. Methods: We are conducting active surveillance in 1 peri-urban and 4 rural communities. During 2 years of surveillance, we expect to enroll an estimated 66,000 newborns within 7 days of their birth and to follow-up them until 59 days of age. Community health workers visit each young infant in the study area 3 times in the first week of life and once a week thereafter. During these visits, community health workers assess the newborns using a clinical algorithm and refer young infants with signs of suspected infection to health care facilities where study physicians reassess them and provide care if needed. On physician confirmation of suspected infection, blood and respiratory specimens are collected and tested to identify the etiologic agent. Conclusions: ANISA is one of the largest initiatives ever undertaken to understand the etiology of young infant infection in low-income countries. The data generated from this surveillance will help guide evidence-based decision making to improve health care in similar settings.

Synthesis of pyrimidine-2,4,6-trione derivatives: Anti-oxidant, anti-cancer, α-glucosidase, β-glucuronidase inhibition and their molecular docking studies.

This paper describes a facile protocol, efficient, and environmentally benign for the synthesis a series of barbiturate acid substituted at C5 position 3a-o. The desired compounds subjected in vitro for different set of bioassays including against anti-oxidant (DPPH and super oxide scavenger assays), anti-cancer, α-glucosidase and β-glucuronidase inhibitions. Compound 3m (IC50=22.9±0.5μM) found to be potent α-glucosidase enzyme inhibitors and showed more activity than standard acarbose (IC50=841±1.73μM). Compound 3f (IC50=86.9±4.33μM) found to be moderate β-Glucuronidase enzyme inhibitors and showed activity comparatively less than the standard d-saccharic acid 1,4-lactone (IC50=45.75±2.16μM). Furthermore, in sillico investigation was carried out to investigate bonding mode of barbiturate acid derivatives.

Synthesis and characterization of 2-substituted benzimidazoles and their evaluation as anticancer agent.

In this work, we report a series of benzimidazole derivatives synthesized from benzene-1,2-diamine and aryl-aldehydes at room temperature. The synthesized compounds have been characterized on the basis of elemental analysis and various spectroscopic studies viz., IR, (1)H- and (13)C-NMR, ESI-MS as well by X-ray single X-ray crystallographic study. Interaction of these compounds with CT-DNA has been examined with fluorescence experiments and showed significant binding ability. All the synthesized compounds have been screened for their antitumor activities against various human cancer cell lines viz., Human breast adenocarcinoma cell line (MCF-7), Human leukemia cell line (THP-1), Human prostate cancer cell lines (PC-3) and adenocarcinomic human alveolar basal epithelial cell lines (A-549). Interestingly, all the compounds showed significant anticancer activity.

Methods Employed in Monitoring and Evaluating Field and Laboratory Systems in the ANISA Study: Ensuring Quality

Background: The Aetiology of Neonatal Infection in South Asia (ANISA) study maintains operations in Bangladesh, India and Pakistan. We developed and deployed a multilayered monitoring system to measure performance indicators of field sites and laboratory operations. This system allows for real-time provision of feedback to study site teams and project stakeholders. The goal of this monitoring and evaluation system is to promote optimal performance and consistency in protocol application at all sites over the course of the study, thereby safeguarding the validity of project findings. This article describes each of the interdependent monitoring layers that were conceptualized, developed and employed by the ANISA coordination team. Methods: Layers of monitoring include site-level, central and database-related activities along with periodic site visitation. We provide a number of real-world examples of how feedback from the ANISA monitoring system directly informs a number of crucial decisions and course corrections during the project. Conclusion: The ANISA monitoring system represents a transparent, understandable and practical resource for development of project monitoring systems in complex multisite health research projects.

Laboratory Methods for Determining Etiology of Neonatal Infection at Population-based Sites in South Asia: The ANISA Study.

Background: The Aetiology of Neonatal Infection in South Asia (ANISA) study aims to determine the etiology of neonatal infections in 5 population-based sites in Bangladesh, India and Pakistan. Methods: The main laboratory challenges in ANISA were selection and consistent implementation of laboratory methods at participating sites with varied infrastructure. The other specific challenges included (1) specimen collection and transport to designated study laboratories and timely processing in rural settings; (2) minimal or nonexistent laboratory facilities at the field sites; (3) obtaining sufficient volumes of blood from enrolled infants aged 0–59 days and (4) caregivers’ concerns about collection of clinical specimens from young infants. An additional challenge was selecting an appropriate molecular platform from multiple available options, all with limited field validation, for use in determining infection in young infants. Conclusions: This article describes how the challenges of specimen collection, transport and processing and implementation of laboratory methods have been addressed in the ANISA study. It also describes the measures taken to improve detection of microorganisms causing young infant infections by enhancing the sensitivity of existing laboratory methods for pathogen detection.

Prevalence, Serotype Distribution and Mortality Risk Associated With Group B Streptococcus Colonization of Newborns in Rural Bangladesh.

Background: Group B Streptococcus (GBS) is a predominant cause of early-onset neonatal sepsis globally; however, the impact of this organism on the health of newborns in South Asia is debated, due in part to a paucity of community-based assessments. We estimated the prevalence and serotypes of GBS colonization of the umbilical cord stump and the association of colonization with mortality in a population-based cohort of newborns in rural Sylhet District, Bangladesh. Methods: Umbilical cord swabs were collected from 646 newborns up to 3 times within the first week after birth (ages <24 hours, ~3 days, ~6 days) and processed to identify GBS serotypes. Results: GBS was isolated from 6.3% (41/646) of newborns. Sixty-one percent of the GBS colonization occurred in neonates within 24 hours of delivery. Serotypes VII (37.1%, n = 13/36) and Ia (33.3%, n = 12/36) were the most predominant colonizing GBS isolates. Other detected serotypes were Ib (11.1%, n = 4/36), II (11.1%, n = 4/36), V (5.6%, n = 2/36) and VI (2.8%, n = 1/36). Mortality risk among newborns with GBS colonization was 6.6 (95% confidence interval: 2.1–20.4) times higher than for those without GBS. Conclusions: The overall prevalence of GBS colonization was lower than in settings, where GBS is a predominant etiology of neonatal illness. In addition, the GBS serotype distribution differed from that reported in the developed part of the world. However, further studies are needed to understand the true burden of GBS-related illness. Mortality risk was substantially increased in the presence of GBS on the umbilical stump, providing support for chlorhexidine antisepsis to the cord to prevent colonization of invasive pathogens.

Synthesis, Molecular Structure and Spectroscopic Investigations of Novel Fluorinated Spiro Heterocycles

This paper describes an efficient and regioselective method for the synthesis of novel fluorinated spiro-heterocycles in excellent yield by cascade [5+1] double Michael addition reactions. The compounds 7,11-bis(4-fluorophenyl)-2,4-dimethyl- 2,4-diazaspiro[5.5] undecane-1,3,5,9-tetraone (3a) and 2,4-dimethyl-7,11-bis (4-(trifluoromethyl)phenyl)-2,4-diazaspiro[5.5]undecane-1,3,5,9-tetraone (3b) were characterized by single-crystal X-ray diffraction, FT-IR and NMR techniques. The optimized geometrical parameters, infrared vibrational frequencies and NMR chemical shifts of the studied compounds have also been calculated using the density functional theory (DFT) method, using Becke-3-Lee-Yang-Parr functional and the 6-311G(d,p) basis set. There is good agreement between the experimentally determined structural parameters, vibrational frequencies and NMR chemical shifts of the studied compounds and those predicted theoretically. The calculated natural atomic charges using NBO method showed higher polarity of 3a compared to 3b.The calculated electronic spectra are also discussed based on the TD-DFT calculations.

A concise synthesis and evaluation of new malonamide derivatives as potential α-glucosidase inhibitors.

A series of new malonamide derivatives were synthesized by Michael addition reaction of N(1),N(3)-di(pyridin-2-yl)malonamide into α,β-unsaturated ketones mediated by DBU in DCM at ambient temperature. The inhibitory potential of these compounds in vitro, against α-glucosidase enzyme was evaluated. Result showed that most of malonamide derivatives were identified as a potent inhibitors of α-glucosidase enzyme. Among all the compounds, 4K (IC50=11.7 ± 0.5 μM) was found out as the most active one compared to standard drug acarbose (IC50=840 ± 1.73 μM). Further cytotoxicity of 4a-4m were also evaluated against a number of cancer and normal cell lines and interesting results were obtained.