Anesthesia for children in Sub-Saharan Africa – a description of settings, common presenting conditions, techniques and outcomes

Anesthesia in developing countries deserves special attention. The most common technique is general anesthesia (with spontaneous or manually assisted ventilation). Nonmedical anesthetists with limited training and supervision and lacking the most common drugs and anesthetic equipment administer anesthesia, usually for emergency surgery. There are important safety issues, especially for pediatric anesthesia. Regarding pediatric surgery, the major workload is due to abdominal emergencies, mainly neonatal bowel obstruction or peritonitis due to typhoid perforation. The morbidity and mortality rate for these conditions is high.     

Precision, signal-to-noise ratio, and dose optimization of magnitude and phase arterial input functions in dynamic susceptibility contrast MRI

PURPOSE: To determine optimal conditions for precise measurement of arterial input function (AIFs) in dynamic susceptibility contrast (DSC) perfusion MRI. MATERIALS AND METHODS: Magnitude-based (DeltaR(2)*) and phase-based (Deltaphi) AIFs were numerically simulated for several doses and baseline MRI noise levels [SNR(I(0))]. Random noise (1000 realizations) was added to real/imaginary MRI signals (derived from an internal carotid AIF), and AIF signal, noise, and signal-to-noise ratio (SNR) were determined. The optimal dose was defined as the dose that maximizes mean AIF SNR over the first-pass (SNR(mean)), rather than SNR at the AIF peak (SNR(peak)) because, compared to SNR(peak), doses predicted by SNR(mean) reduced the AIF-induced variability in cerebral blood flow (CBF) by 24% to 40%. RESULTS: The AIF SNR is most influenced by choice of AIF signal, then optimal dosing, each with little penalty. Compared to DeltaR(2)*, Deltaphi signal has 4 to 80 times the SNR over all doses and time points, and approximately 10-fold SNR(mean) at respective optimal doses. Optimal doses induce 85% to 90% signal drop for the DeltaR(2)* method, and 70% to 75% for Deltaphi, with two-fold dose errors causing approximately 1.7-fold loss in SNR(mean). Increases in SNR(I(0)) proportionally increase AIF SNR, but at a cost. CONCLUSION: AIF SNR is affected most by signal type, then dosing, and lastly, SNR(I(0)).     

Endometrial stromal cells and immune cell populations within lymph nodes in a nonhuman primate model of endometriosis

Mounting evidence suggests that immunological responses may be altered in endometriosis. The baboon (Papio anubis) is generally considered the best model of endometriosis pathogenesis. The objective of the current study was to investigate for the first time immunological changes within uterine and peritoneal draining lymph nodes in a nonhuman primate baboon model of endometriosis. Paraffin-embedded femoral lymph nodes were obtained from 22 normally cycling female baboons (induced endometriosis n = 11; control n = 11). Immunohistochemical staining was performed with antibodies for endometrial stromal cells, T cells, immature and mature dendritic cells, and B cells. Lymph nodes were evaluated using an automated cellular imaging system. Endometrial stromal cells were significantly increased in lymph nodes from animals with induced endometriosis, compared to control animals (P = .033). In animals with induced endometriosis, some lymph node immune cell populations including T cells, dendritic cells and B cells were increased, suggesting an efficient early response or peritoneal drainage.     

Detection of Problem Gambler Subgroups Using Recursive Partitioning

The multivariate socio-demographic risk factors for problem gambling have been well documented. While this body of research is valuable in determining risk factors aggregated across various populations, the majority of studies tend not to specifically identify particular subgroups of problem gamblers based on the interaction between variables. The identification of problem gambling subgroups offers the potential for improved harm-reduction initiatives in particular geographic contexts. We introduce an analytical approach termed recursive partitioning, commonly used in the health sciences but infrequently employed in gambling research, to identify specific gambler subgroups based on the interaction of a range of predictor variables. Recursive partitioning creates groups of cases (e.g. gamblers) with similar outcomes by repeatedly splitting each group into smaller and more homogenous subgroups. We employ it to define problem gambler subgroups within a diverse population context (i.e. northern Australia) and compare the results with a multivariate analysis of the same dataset using a generalized linear regression model. We assess the advantages and disadvantages of each approach, and argue that recursive partitioning is an easily-interpretable approach that may be useful both in identifying problem gambling subgroups and in developing targeted harm-minimisation strategies.     

Performance of the Vitek MS v2.0 System in Distinguishing Streptococcus pneumoniae from Nonpneumococcal Species of the Streptococcus mitis Group

The Vitek MS v2.0 matrix-assisted laser desorption ionization–time of flight mass spectrometry system accurately distinguished Streptococcus pneumoniae from nonpneumococcal S. mitis group species. Only 1 of 116 nonpneumococcal isolates (<1%) was misidentified as S. pneumoniae. None of 95 pneumococcal isolates was misidentified. This method provides a rapid, simple means of discriminating among these challenging organisms.     

Cell tracking technologies for acute ischemic brain injury

Stem cell therapy has showed considerable potential in the treatment of stroke over the last decade. In order that these therapies may be optimized, the relative benefits of growth factor release, immunomodulation, and direct tissue replacement by therapeutic stem cells are widely under investigation. Fundamental to the progress of this research are effective imaging techniques that enable cell tracking in vivo. Direct analysis of the benefit of cell therapy includes the study of cell migration, localization, division and/or differentiation, and survival. This review explores the various imaging tools currently used in clinics and laboratories, addressing image resolution, long-term cell monitoring, imaging agents/isotopes, as well as safety and costs associated with each technique. Finally, burgeoning tracking techniques are discussed, with emphasis on multimodal imaging.