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

Correlates of Out-of-Pocket and Catastrophic Health Expenditures in Tanzania: Results from a National Household Survey.

Inequality in health services access and utilization are influenced by out-of-pocket health expenditures in many low and middle-income countries (LMICs). Various antecedents such as social factors, poor health and economic factors are proposed to direct the choice of health care service use and incurring out-of-pocket payments. We investigated the association of these factors with out-of-pocket health expenditures among the adult and older population in the United Republic of Tanzania. We also investigated the prevalence and associated determinants contributing to household catastrophic health expenditures. We accessed the data of a multistage stratified random sample of 7279 adult participants, aged between 18 and 59 years, as well as 1018 participants aged above 60 years, from the first round of the Tanzania National Panel survey. We employed multiple generalized linear and logistic regression models to evaluate the correlates of out-of-pocket as well as catastrophic health expenditures, accounting for the complex sample design effects. Increasing age, female gender, obesity and functional disability increased the adults' out-of-pocket health expenditures significantly, while functional disability and visits to traditional healers increased the out-of-pocket health expenditures in older participants. Adult participants, who lacked formal education or worked as manual laborers earned significantly less (p < 0.001) and spent less on health (p < 0.001), despite having higher levels of disability. Large household size, household head's occupation as a manual laborer, household member with chronic illness, domestic violence against women and traditional healer's visits were significantly associated with high catastrophic health expenditures. We observed that the prevalence of inequalities in socioeconomic factors played a significant role in determining the nature of both out-of-pocket and catastrophic health expenditures. We propose that investment in social welfare programs and strengthening the social security mechanisms could reduce the financial burden in United Republic of Tanzania

Midline Signalling Systems Direct the Formation of a Neural Map by Dendritic Targeting in the Drosophila Motor System

During embryonic development of the motor system of Drosophila, motorneurons target their dendrites to different regions along the body axis in response to midline guidance cues

Multiple network properties overcome random connectivity to enable stereotypic sensory responses

Connections between neuronal populations may be genetically hardwired or random. In the insect olfactory system, projection neurons of the antennal lobe connect randomly to Kenyon cells of the mushroom body. Consequently, while the odor responses of the projection neurons are stereotyped across individuals, the responses of the Kenyon cells are variable. Surprisingly, downstream of Kenyon cells, mushroom body output neurons show stereotypy in their responses. We found that the stereotypy is enabled by the convergence of inputs from many Kenyon cells onto an output neuron, and does not require learning. The stereotypy emerges in the total response of the Kenyon cell population using multiple odor-specific features of the projection neuron responses, benefits from the nonlinearity in the transfer function, depends on the convergence:randomness ratio, and is constrained by sparseness. Together, our results reveal the fundamental mechanisms and constraints with which convergence enables stereotypy in sensory responses despite random connectivity

Visualization and Analysis of 3D Microscopic Images

In a wide range of biological studies, it is highly desirable to visualize and analyze three-dimensional (3D) microscopic images. In this primer, we first introduce several major methods for visualizing typical 3D images and related multi-scale, multi-time-point, multi-color data sets. Then, we discuss three key categories of image analysis tasks, namely segmentation, registration, and annotation. We demonstrate how to pipeline these visualization and analysis modules using examples of profiling the single-cell gene-expression of C. elegans and constructing a map of stereotyped neurite tracts in a fruit fly brain

Matrix metalloproteinases (MMP-2,9) and their tissue inhibitors (TIMP-1,2) as novel markers of stress response and atherogenesis in children with chronic kidney disease (CKD) on conservative treatment

The system of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) may play a key role in atherogenesis of chronic kidney disease (CKD) patients by its impact on matrix accumulation. Connections with inflammation, stress, or endothelial dysfunction are also probable. However, the data on correlations between these parameters in CKD patients are scarce in adults and absent in children. The aim of our study was to evaluate serum concentrations of MMP-2, MMP-9, TIMP-1, and TIMP-2, as well as their correlations with markers of stress response (Hsp90-α, anti-Hsp60), endothelial dysfunction (sE-selectin), and inflammation (high-sensitivity C-reactive protein) in CKD children treated conservatively. Thirty-seven patients were divided into two groups according to the CKD stage (gr.CKDI, 19 children with CKD stages 2–3; gr.CKDII, 18 subjects with CKD stages 4–5). Twenty-four age-matched healthy subjects served as controls. Serum concentrations of MMP-2, MMP-9, TIMP-1, TIMP-2, Hsp90-α, anti-Hsp60, and sE-selectin were assessed by ELISA. Median values of MMP-2, MMP-9, TIMP-1, and TIMP-2 were significantly higher in all CKD children vs. controls and were increased in patients with CKD stages 4–5 vs. CKD stages 2–3. Hsp90-α, anti-Hsp60, sE-selectin, and glomerular filtration rate predicted the values of MMPs and TIMPs. Chronic kidney disease in children is characterized by MMP/TIMP system dysfunction, aggravated by the progression of renal failure. Correlations between examined parameters, heat shock proteins, and markers of endothelial damage suggest the possibility of MMP/TIMP application as indicators of stress response and atherogenesis in children with CKD on conservative treatment

A glial amino-acid transporter controls synapse strength and courtship in Drosophila

Mate choice is an evolutionarily critical decision that requires the detection of multiple sex-specific signals followed by central integration of these signals to direct appropriate behavior. The mechanisms controlling mate choice remain poorly understood. Here, we show that the glial amino-acid transporter genderblind controls whether Drosophila melanogaster males will attempt to mate with other males. Genderblind (gb) mutant males showed no alteration in heterosexual courtship or copulation, but were attracted to normally unappealing male species-specific chemosensory cues. As a result, genderblind mutant males courted and attempted to copulate with other Drosophila males. This homosexual behavior could be induced within hours using inducible RNAi, suggesting that genderblind controls nervous system function rather than its development. Consistent with this, and indicating that glial genderblind regulates ambient extracellular glutamate to suppress glutamatergic synapse strength in vivo, homosexual behavior could be turned on and off by altering glutamatergic transmission pharmacologically and/or genetically

Glycan labeling strategies and their use in identification and quantification

Most methods for the analysis of oligosaccharides from biological sources require a glycan derivatization step: glycans may be derivatized to introduce a chromophore or fluorophore, facilitating detection after chromatographic or electrophoretic separation. Derivatization can also be applied to link charged or hydrophobic groups at the reducing end to enhance glycan separation and mass-spectrometric detection. Moreover, derivatization steps such as permethylation aim at stabilizing sialic acid residues, enhancing mass-spectrometric sensitivity, and supporting detailed structural characterization by (tandem) mass spectrometry. Finally, many glycan labels serve as a linker for oligosaccharide attachment to surfaces or carrier proteins, thereby allowing interaction studies with carbohydrate-binding proteins. In this review, various aspects of glycan labeling, separation, and detection strategies are discussed