Schistosomiasis and the Dogon country (Mali)

A previously unknown area of schistosomiasis transmission is reported based on findings from a travelers' clinic in Barcelona. Three species of Schistosoma (S. haematobium, S. mansoni, and S. intercalatum) were diagnosed in a cluster of 43 patients who had been swimming in the Bandiagara and Bankas districts of Mali, where the Dogon people live. Three villages in the Bankas district appear to harbor these three species. The transmission potential of such a focus in this area is outlined. The travelers involved had little or no information on the risks of contracting schistosomiasis in that area. Obtaining a traveler's history, including accurate geographic data, is shown to be a crucial asset for improving epidemiologic research.     

Systematic Review and Meta-analysis of Short- versus Long-Acting Granulocyte Colony-Stimulating Factors for Reduction of Chemotherapy-Induced Febrile Neutropenia

Introduction

Short- and long-acting granulocyte-colony stimulating factors (G-CSFs) are approved for the reduction of febrile neutropenia. A systematic literature review was performed to identify randomized controlled trials (RCTs) and non-RCTs reporting the use of G-CSFs following chemotherapy treatment.

Methods

Medline^®/Medline in-process, Embase^®, and the Cochrane Library were searched for studies published between January 2003 and June 2016. A hand-search of relevant conference proceedings was conducted for meetings held between 2012 and 2016. Eligible studies were restricted to those reporting a direct, head-to-head comparison of short- versus long-acting G-CSFs for reduction of chemotherapy-induced febrile neutropenia. Risk-of-bias assessments were performed for full publications only.

Results

The search strategy yielded 4044 articles for electronic screening. Thirty-six publications were evaluated for the meta-analysis: 11 of 12 RCTs and 2 of 24 non-RCTs administered doses of the short-acting G-CSF filgrastim for ≥?7 days. In RCT studies, there was no statistically significant difference in outcomes of interest between short- and long-acting G-CSFs. In non-RCTs, the overall risk was lower with long-acting G-CSF than with short-acting G-CSF for incidence of febrile neutropenia [overall relative risk (RR)?=?0.67, P ?=?0.023], hospitalizations (overall RR?=?0.68, P ?<?0.05), and chemotherapy dose delays (overall RR?=?0.68, P? =?0.020).

Conclusions

Overall, the weight of evidence from RCTs indicates little difference in efficacy between the short- and long-acting G-CSFs if dosed according to recommended guidelines. There is some evidence for greater efficacy for long-acting G-CSFs in non-RCTs, which may be a result of under-dosing of short-acting G-CSFs in general practice in real-world usage.

Funding

Hospira Inc, which was acquired by Pfizer Inc in September 2015, and Pfizer Inc.

     

Etiology of diarrhea in children younger than 5 years of age admitted in a rural hospital of southern Mozambique

Diarrhea is one of the main causes of morbidity and mortality among children in sub-Saharan Africa and one of the main causes of hospital admissions in rural areas. Stool samples were collected from 529 children admitted with diarrhea to the Manhi?a District Hospital (September 2000 to September 2001) and processed to detect bacterial enteropathogens, parasites, and virus. Diarrheagenic Escherichia coli, isolated from 120 samples (22.6%; enteroaggregative [corrected] [9.6%], enterotoxigenic [6.8%], enteropathogenic [corrected] [4.3%], and verotoxigenic [1.9%]) was the most frequently isolated pathogen, followed by Ascaris lumbricoides (9.3%). Others detected included Salmonella spp. and Giardia lamblia (2.5% each) and Campylobacter spp. (1.7%). A. lumbricoides (92% versus 8%; P<0.001) and Strongyloides stercolaris (100% versus 0%; P=0.008) were most frequently isolated in children older than 12 months of age. Resistance to trimethoprim-sulphametoxazole and ampicillin was high. Etiologic data on diarrheal diseases and susceptibility patterns of diarrheal pathogens are important tools for clinical management and control strategic planning.     

Low concentrations of ketamine initiate dendritic atrophy of differentiated GABAergic neurons in culture

Administration of subanesthetic concentrations of ketamine, a noncompetitive antagonist of the N-methyl-d-aspartate (NMDA) type of glutamate receptors, is a widely accepted therapeutic modality in perioperative and chronic pain management. Although extensive clinical use has demonstrated its safety, recent human histopathological observations as well as laboratory data suggest that ketamine can exert adverse effects on central nervous system neurons. To further investigate this issue, the present study was designed to evaluate the effects of ketamine on the survival and dendritic arbor architecture of differentiated gamma-aminobutyric acidergic (GABAergic) interneurons in vitro. We show that short-term exposure of cultures to ketamine at concentrations of > or =20 microg/ml leads to a significant cell loss of differentiated cells and that non-cell death-inducing concentrations of ketamine (10 microg/ml) can still initiate long-term alterations of dendritic arbor in differentiated neurons, including dendritic retraction and branching point elimination. Most importantly, we also demonstrate that chronic (>24 h) administration of ketamine at concentrations as low as 0.01 microg/ml can interfere with the maintenance of dendritic arbor architecture. These results raise the possibility that chronic exposure to low, subanesthetic concentrations of ketamine, while not affecting cell survival, could still impair neuronal morphology and thus might lead to dysfunctions of neural networks.     

Potentially toxic effects of anaesthetics on the developing central nervous system

A growing body of experimental evidence suggests that anaesthetics, by influencing GABAergic and glutaminergic neural signalling, can have adverse effects on the developing central nervous system. The biological foundation for this is that gamma-aminobutyric acid and glutamate could act non-synaptically, in addition to their role in neurotransmission in the adult brain, in the regulation of neuronal development in the central nervous system. These neurotransmitters and their receptors are expressed from very early stages of central nervous system development and appear to influence neural progenitor proliferation, cell migration and neuronal differentiation. During the synaptogenetic period, pharmacological blockade of N-methyl-d-aspartate (NMDA)-type glutamate receptors as well as stimulation of GABAA receptors has been reported to be associated with increased apoptosis in the developing brain. Importantly, recent data suggest that even low, non-apoptogenic concentrations of anaesthetics can perturb neuronal dendritic development and thus could potentially lead to impairment of developing neuronal networks. The extrapolation of these experimental observations to clinical practice is of course very difficult and requires extreme caution as differences in drug concentrations and exposure times as well as interspecies variations are all important confounding variables. While clinicians should clearly not withhold anaesthesia based on current animal studies, these observations should urge more laboratory and clinical research to further elucidate this issue.     

Is there a genetic signature for liver metastasis in colorectal cancer？

Even though liver metastasis accounts for the vast majority of cancer deaths in patients with colorectal cancer （CRC）, fundamental questions about the molecular and cellular mechanisms of liver metastasis still remain unanswered. Determination of gene expression profiles by microarray technology has improved our knowledge of CRC molecular pathways. However, defined gene signatures are highly variable among studies. Expression profiles and molecular markers have been specifically linked to liver metastases mechanistic paths in CRC. However, to date, none of the identified signatures or molecular markers has been successfully validated as a diagnostic or prognostic tool applicable to routine clinical practice. To obtain a genetic signature for liver metastasis in CRC, measures to improve reproducibility, to increase consistency, and to validate results need to be implemented. Alternatives to expression profiling with microarray technology are continuing to be used. In the recent past, many genes codifying for proteins that are directly or indirectly involved in adhesion, invasion, angiogenesis, survival and cell growth have been linked to mechanisms of liver metastases in CRC.     

Polysialic acid-neural cell adhesion molecule in brain plasticity: from synapses to integration of new neurons

Isoforms of the neuronal cell adhesion molecule (NCAM) carrying the linear homopolymer of alpha 2,8-linked sialic acid (polysialic acid, PSA) have emerged as particularly attractive candidates for promoting plasticity in the nervous system. The large negatively charged PSA chain of NCAM is postulated to be a spacer that reduces adhesion forces between cells allowing dynamic changes in membrane contacts. Accumulating evidence also suggests that PSA-NCAM-mediated interactions lead to activation of intracellular signaling cascades that are fundamental to the biological functions of the molecule. An important role of PSA-NCAM appears to be during development, when its expression level is high and where it contributes to the regulation of cell shape, growth or migration. However, PSA-NCAM does persist in adult brain structures such as the hippocampus that display a high degree of plasticity where it is involved in activity-induced synaptic plasticity. Recent advances in the field of PSA-NCAM research have not only consolidated the importance of this molecule in plasticity processes but also suggest a role for PSA-NCAM in the regulation of higher cognitive functions and psychiatric disorders. In this review, we discuss the role and mode of actions of PSA-NCAM in structural plasticity as well as its potential link to cognitive processes.