52 research outputs found
Toll-like receptor-4 299Gly allele is associated with Guillain-Barre syndrome in Bangladesh
Objective: TLR4 plays an important role in the pathogenesis of Guillain-Barre
syndrome (GBS). The relationships between TLR4 polymorphisms and susceptibility to GBS are poorly understood. We investigated the frequency and
assessed the association of two single nucleotide polymorphisms (SNPs) in the
extracellular domain of TLR4 (Asp299Gly and Thr399Ile) with disease susceptibility and the clinical features of GBS in a Bangladeshi cohort. Methods: A total
of 290 subjects were included in this study: 141 patients with GBS and 149
unrelated healthy controls. The TLR4 polymorphisms Asp299Gly and Thr399Ile
were genotyped using polymerase chain reaction-restriction fragment length
polymorphism (PCR-RFLP) assay. Results: The minor 299Gly allele was significantly associated with GBS susceptibility (P = 0.0137, OR = 1.97, 95%
CI = 1.17â3.31), and was present at a significantly higher frequency in patients
with the acute motor axonal neuropathy (AMAN) subtype of GBS (P = 0.0120,
OR = 2.37, 95% CI = 1.26â4.47) than acute inflammatory demyelinating
polyneuropathy (AIDP) subtype (P = 0.961, OR = 1.15, 95% CI = 0.38â3.48);
when compared to healthy controls. The genotype frequency of the Asp299Gly
polymorphism was not significantly different between patients with GBS and
healthy controls. The Asp299-Thr399 haplotype was associated with a significantly lower risk of developing GBS (P = 0.0451, OR = 0.63, 95% CI = 0.40â
0.99). No association was observed between the Thr399Ile polymorphism and
GBS disease susceptibility. Interpretation: The TLR4 minor 299Gly allele was
associated with increased susceptibility to GBS and the axonal GBS subtype in
the Bangladeshi population. However, no associations were observed between
the genotypes of the Asp299Gly and Thr399Ile SNPs and antecedent C. jejuni
infection or disease severity in Bangladeshi patients with GBS
Automated Reconstruction of Neuronal Morphology Based on Local Geometrical and Global Structural Models
Digital reconstruction of neurons from microscope images is an important and challenging problem in neuroscience. In this paper, we propose a model-based method to tackle this problem. We first formulate a model structure, then develop an algorithm for computing it by carefully taking into account morphological characteristics of neurons, as well as the image properties under typical imaging protocols. The method has been tested on the data sets used in the DIADEM competition and produced promising results for four out of the five data sets
Increased waterborne blaNDM-1 resistance gene abundances associated with seasonal human pilgrimages to the Upper Ganges River
Antibiotic resistance (AR) is often rooted in inappropriate antibiotic use, but poor water quality and inadequate sanitation exacerbate the problem, especially in emerging countries. An example is increasing multi-AR due to mobile carbapenemases, such as NDM-1 protein (coded by blaNDM-1 genes), which can produce extreme drug-resistant phenotypes. In 2010, NDM-1 positive isolates and blaNDM-1 genes were detected in surface waters across Delhi and have since been detected across the urban world. However, little is known about blaNDM-1 levels in more pristine locations, such as the headwaters of the Upper Ganges River. This area is of particular interest because it receives massive numbers of visitors during seasonal pilgrimages in May/June, including visitors from urban India. Here we quantified blaNDM-1 abundances, other AR genes (ARG) and coliform bacteria in sediments and water column samples from seven sites in the Rishikesh-Haridwar region of the Upper Ganges and five sites on the Yamuna River in Delhi to contrast blaNDM-1 levels and water quality conditions between season and region. Water quality in the Yamuna was very poor (e.g., anoxia at all sites), and blaNDM-1 abundances were high across sites in water (5.4 ± 0.4 log(blaNDM-1·mL-1); 95% confidence interval) and sediment (6.3 ± 0.7 log(blaNDM-1·mg-1)) samples from both seasons. In contrast, water column blaNDM-1 abundances were very low across all sites (2.1 ± 0.6 log(blaNDM-1·mL-1)) in February in the Upper Ganges and water quality was good (e.g., near saturation oxygen). However, per capita blaNDM-1 levels were 20 times greater in June in the Ganges water column relative to February and blaNDM-1 levels significantly correlated with fecal coliform levels (r=0.61; p=0.007). Given waste management infrastructure is limited in Rishikesh-Haridwar; data imply blaNDM-1 levels are higher in visitor's wastes than local residents, which results in seasonally higher blaNDM-1 levels in the river. Pilgrimage areas without adequate waste treatment are possible "hot spots" for AR transmission, and waste treatment must be improved to reduce broader AR dissemination via exposed returning visitors
Management practices and performance of mergers and acquisitions in Pakistan: mediating role of psychological contract
Soil geochemistry confines microbial abundances across an arctic landscape; implications for net carbon exchange with the atmosphere
Changing perspectives on the internationalization of R&D and innovation by multinational enterprises: a review of the literature
Internationalization of R&D and innovation by Multinational Enterprises (MNEs) has undergone a gradual and comprehensive change in perspective over the past 50 years. From sporadic works in the late 1950s and in the 1960s, it became a systematically analysed topic in the 1970s, starting with pioneering reports and âfoundation textsâ. Our review unfolds the theoretical and empirical evolution of the literature from dyadic interpretations of centralization versus decentralization of R&D by MNEs to more comprehensive frameworks, wherein established MNEs from Advanced Economies still play a pivotal role, but new players and places also emerge in the global generation and diffusion of knowledge. Hence views of R&D internationalization increasingly rely on concepts, ideas and methods from IB and other related disciplines such as industrial organization, international economics and economic geography. Two main findings are highlighted. First, scholarly research pays an increasing attention to the network-like characteristics of international R&D activities. Second, different streams of literature have emphasized the role of location- specific factors in R&D internationalization. The increasing emphasis on these aspects has created new research opportunities in some key areas, including inter alia: cross-border knowledge sourcing strategies, changes in the geography of R&D and innovation, and the international fragmentation of production and R&D activities
Hybrid microalgae-activated sludge system for carbon-efficient wastewater treatment
Engineered microalgae-bacteria systems can play a key role in the realisation of energy-efficient carbon-neutral wastewater treatment technologies. An attempt was made to develop a hybrid microalgae-activated sludge (HMAS) system coupling carbon capture with domestic wastewater treatment. Photobioreactors internally illuminated with red light-emitting diodes (LEDs), and inoculated with mixed microbial culture, resulted in substantial savings in operational cost. System performance was evaluated at about 600 ÎŒmol/m2 s LED irradiance while treating synthetic municipal wastewater in a chemostat for about 2 months, containing about 250 mg/L soluble chemical oxygen demand (SCOD), 90 mg/L NH3-N and 10 mg/L orthophosphate. Carbon dioxide was supplied into the HMAS at 25 mL/min, 25% v/v. SCOD was efficiently removed from the wastewater (up to 70%) and bacterial oxygen requirement of >2 mg/L was met through microalgal photosynthesis. The system demonstrated its potential in achieving carbon-efficient wastewater treatment.
HIGHLIGHTS
A hybrid microalgae-activated sludge (HMAS) system coupling carbon capture with wastewater treatment.;
Up to 75% soluble chemical oxygen demand removal achieved.;
Ammonium removal efficiencies greater than 90% were achieved in all the bioreactors.;
Need for external aeration was eliminated by satisfying bacterial oxygen requirements.;
Need for further studies with other types of wastewater.
Hospital Wastewater Releases of Carbapenem-Resistance Pathogens and Genes in Urban India
Increasing
antibiotic resistant hospital-acquired infections and
limited new antibiotic discovery are jeopardizing human health at
global scales, although how hospitals themselves fuel antimicrobial
resistance (AMR) in the wider environment is largely unknown. Antibiotic
resistance (AR) in hospitals in countries such as India is potentially
problematic because of high antibiotic use, overcrowding, and inadequate
wastewater containment. Here we quantified fecal coliforms (FC), carbapenem-resistant
Enterobacteriaceae (CRE), <i>bla</i><sub><i>NDMâ1</i></sub>, and selected extended-spectrum ÎČ-lactam (ESBL) resistant
bacteria and genes in 12 hospital wastewater outfalls and five background
sewer drains across New Delhi over two seasons. Hospital wastewaters
had up to 9 orders of magnitude greater concentrations of CRE bacteria
and <i>bla</i><sub>NDMâ1</sub> than local sewers
(depending on the hospital), implying hospitals contribute high concentrations
of AR relative to community sources in Delhi, especially during the
winter. Significant correlations were found between FC levels (a fecal
indictor), and CRE (<i>r</i> = 0.924; <i>p</i> = 0.005), <i>bla</i><sub>NDMâ1</sub> (<i>r</i> = 0.934, <i>p</i> = 0.009), and ESBL-resistant bacteria
(<i>r</i> = 0.913, <i>p</i> = 0.010) levels across
hospital wastewaters, respectively, implying that elevated CRE and <i>bla</i><sub>NDMâ1</sub> are of patient origin. However,
of greater importance to global health, microbial culturing found
18 to 41% of wastewater CRE isolates (<i>n</i> = 1447) were
on the WHO âcritical pathogenâ list in urgent need of
new antibiotics, and 55% of CRE isolates from larger hospitals carried
at least one <i>bla</i><sub>NDMâ1</sub> gene. Wastewater
releases from New Delhi hospitals may pose a greater AR exposure risk
to residents than believed, implying in-hospital antibiotic use must
be better controlled and more effective waste treatment is needed
for hospital wastewaters
Tollâlike receptorâ4 299Gly allele is associated with GuillainâBarrĂ© syndrome in Bangladesh
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