Temporal trends in severe malaria in Chittagong, Bangladesh

ABSTRACT: BACKGROUND: Epidemiological data on malaria in Bangladesh are sparse, particularly on severe and fatal malaria. This hampers the allocation of healthcare provision in this resource-poor setting. Over 85% of the estimated 150,000-250,000 annual malaria cases in Bangladesh occur in Chittagong Division with 80% in the Chittagong Hill Tracts (CHT). Chittagong Medical College Hospital (CMCH) is the major tertiary referral hospital for severe malaria in Chittagong Division. METHODS: Malaria screening data from 22,785 inpatients in CMCH from 1999-2011 were analysed to investigate the patterns of referral, temporal trends and geographical distribution of severe malaria in Chittagong Division, Bangladesh. RESULTS: From 1999 till 2011, 2,394 malaria cases were admitted, of which 96% harboured Plasmodium falciparum and 4% Plasmodium vivax. Infection was commonest in males (67%) between 15 and 34 years of age. Seasonality of malaria incidence was marked with a single peak in P. falciparum transmission from June to August coinciding with peak rainfall, whereas P. vivax showed an additional peak in February-March possibly representing relapse infections. Since 2007 there has been a substantial decrease in the absolute number of admitted malaria cases. Case fatality in severe malaria was 18% from 2008-2011, remaining steady during this period. A travel history obtained in 226 malaria patients revealed only 33% had been to the CHT in the preceding three weeks. Of all admitted malaria patients, only 9% lived in the CHT, and none in the more remote malaria endemic regions near the Indian border. CONCLUSIONS: The overall decline in admitted malaria cases to CMCH suggests recent control measures are successful. However, there are no reliable data on the incidence of severe malaria in the CHT, the most endemic area of Bangladesh, and most of these patients do not reach tertiary health facilities. Improvement of early treatment and simple supportive care for severe malaria in remote areas and implementation of a referral system for cases requiring additional supportive care could be an important component of further reducing malaria-attributable disease and death in Bangladesh.     

Gait Biomechanics of Individuals with Transtibial Amputation: Effect of Suspension System

Prosthetic suspension system is an important component of lower limb prostheses. Suspension efficiency can be best evaluated during one of the vital activities of daily living, i.e. walking. A new magnetic prosthetic suspension system has been developed, but its effects on gait biomechanics have not been studied. This study aimed to explore the effect of suspension type on kinetic and kinematic gait parameters during level walking with the new suspension system as well as two other commonly used systems (the Seal-In and pin/lock). Thirteen persons with transtibial amputation participated in this study. A Vicon motion system (six cameras, two force platforms) was utilized to obtain gait kinetic and kinematic variables, as well as pistoning within the prosthetic socket. The gait deviation index was also calculated based on the kinematic data. The findings indicated significant difference in the pistoning values among the three suspension systems. The Seal-In system resulted in the least pistoning compared with the other two systems. Several kinetic and kinematic variables were also affected by the suspension type. The ground reaction force data showed that lower load was applied to the limb joints with the magnetic suspension system compared with the pin/lock suspension. The gait deviation index showed significant deviation from the normal with all the systems, but the systems did not differ significantly. Main significant effects of the suspension type were seen in the GRF (vertical and fore-aft), knee and ankle angles. The new magnetic suspension system showed comparable effects in the remaining kinetic and kinematic gait parameters to the other studied systems. This study may have implications on the selection of suspension systems for transtibial prostheses.

Trial Registration

Iranian Registry of Clinical Trials IRCT2013061813706N1.     

Human serum promotes the proliferation but not the stemness genes expression of human adipose-derived stem cells

Recently human adipose-derived stem cells (ASCs) have shown much therapeutic potential in regenerative medicine. However, fetal bovine serum (FBS) used in culturing human cells may give risk to viral and prion transmission as well as immune rejection. Human serum (HS) is a safer growth supplement in human cell culture but its effects have not been well established. Therefore the objectives of this study were to compare the effects of HS versus FBS on the proliferation and stemness gene expression of ASCs. ASCs were cultured for 5 passages in medium supplemented with either 10% HS or 10% FBS. ASCs proliferation rate and viability were determined at every passage. Total RNA was extracted at passage 5 (P5) and quantitative PCR was carried out to determine the stemness gene expression level of SOX-2, Nanog3, BST-1, REX-1, ABCG2 and FGF-4. The results showed ASC cultured in 10% HS scored greater proliferation rates and viability compared to 10% FBS. ASCs proliferated significantly faster in 10% HS compared to 10% FBS at P2, P3, and P4 (p < 0.05). In quantitative gene expression analysis, ASCs cultured in 10% FBS showed a significant increase of BST-1, REX-1 and ABCG2 expression compared to 10% HS. In conclusion, HS promotes ASCs proliferation and viability but its ability to support the stemness property of ASCs was inferior to FBS.     

Ovarian development and histological observations of threatened dwarf snakehead fish,Channa gachua (Hamilton, 1822)

Channa gachua were monthly sampled throughout a year and the histological analysis of their ovaries was done to determine the changes occurring in ovarian development. Based on histological examination of the ovaries, the oogenic process of C. gachua undergoes distinct cyclic and seasonal morphological changes. Five different developmental stages were identified under three major categories: pre-spawning (immature, maturing, mature), spawning (ripe-running) and post-spawning (spent). The peak spawning period of C. gachua was noticed during December - February. The gonadosomatic index (GSI) and ova diameter ranged from 0.79 to 3.61% and 543–1123 μm respectively. The highest mean GSI (3.61 ± 0.16) and oocyte diameter (1123 ± 55 μm) were observed in December indicating that during this month the gonadal development reached maturity.     

Effects of partial selfing on the equilibrium genetic variance,mutation load,and inbreeding depression under stabilizing selection

The mating system of a species is expected to have important effects on its genetic diversity. In this article, we explore the effects of partial selfing on the equilibrium genetic variance V_g, mutation load L, and inbreeding depression δ under stabilizing selection acting on a arbitrary number n of quantitative traits coded by biallelic loci with additive effects. When the ratio is low (where U is the total haploid mutation rate on selected traits) and effective recombination rates are sufficiently high, genetic associations between loci are negligible and the genetic variance, mutation load, and inbreeding depression are well predicted by approximations based on single‐locus models. For higher values of and/or lower effective recombination, moderate genetic associations generated by epistasis tend to increase V_g, L, and δ, this regime being well predicted by approximations including the effects of pairwise associations between loci. For yet higher values of and/or lower effective recombination, a different regime is reached under which the maintenance of coadapted gene complexes reduces V_g, L, and δ. Simulations indicate that the values of V_g, L, and δ are little affected by assumptions regarding the number of possible alleles per locus.     

Measures,Gaps, and Mitigation Strategies in Bangladesh’s COVID-19 Response

EcoHealth - The Coronavirus Disease 2019 (COVID-19) spread rapidly from China to most other countries around the world in early 2020 killing millions of people. To prevent virus spread, world...     

Effect of the alpha3beta1 integrin on the IL-1 stimulated activation of c-Jun N-terminal kinase (JNK) in CACO-2 cells

Intestinal epithelial cells (IEC) are capable of responding to IL-1 stimulation by producing a variety of pro-inflammatory cytokines. Recently, we have found that binding of the alpha3beta1 integrin may have a regulatory effect on IL-1 responses and intracellular signaling by suppressing cytokine secretion, mRNA expression and the downstream intracellular signaling events from IKK to NF-kappaB activation. In this study, we extend these findings by showing that treatment of the Caco-2 epithelial cells with a cross-linking anti-alpha3 integrin antibody resulted in a suppression in the levels of IL-1 induced AP-1 binding activity in nuclear extracts. Furthermore, suppressed levels of IL-1 induced c-Jun N-terminal kinase (JNK) phosphorylation and kinase activity were seen with the antibody treated cells. Cells cultured on purified laminin-5, the ligand for the alpha3beta1 integrin, did not show significantly elevated levels of JNK phosphorylation after IL-1 stimulation while cells cultured on fibronectin yielded significantly elevated levels of IL-1 induced JNK phosphorylation. These results indicate that binding of the alpha3beta1 integrin results in a suppression in the activation of the IL-1 induced intracellular signaling pathway from JNK to AP-1. This novel regulatory effect may be a potentially important mechanism to regulate IL-1 mediated responses by IEC.     

Elevated expression of DNA polymerase II increases spontaneous mutagenesis in Escherichia coli

Escherichia coli DNA polymerase II (Pol-II), encoded by the SOS-regulated polB gene, belongs to the highly conserved group B (-like) family of “high-fidelity” DNA polymerases. Elevated expression of polB gene was recently shown to result in a significant elevation of translesion DNA synthesis at 3, N⁴-ethenocytosine lesion with concomitant increase in mutagenesis. Here, I show that elevated expression of Pol-II leads to an approximately 100-fold increase in spontaneous mutagenesis in a manner that is independent of SOS, umuDC, dinB, recA, uvrA and mutS functions. Cells grow slowly and filament with elevated expression of Pol-II. Introduction of carboxy terminus (“β interaction domain”) mutations in polB eliminates elevated spontaneous mutagenesis, as well as defects in cell growth and morphology, suggesting that these abilities require the interaction of Pol-II with the β processivity subunit of DNA polymerase III. Introduction of a mutation in the proofreading exo motif of polB elevates mutagenesis by a further 180-fold, suggesting that Pol-II can effectively compete with DNA polymerase III for DNA synthesis. Thus, Pol-II can contribute to spontaneous mutagenesis when its expression is elevated.