We have isolated 165 Caenorhabditis elegans mutants, representing 21 Synaptic transmission is a major mechanism for intercellular communication in the nervous system. Many of the events that mediate synaptic transmission occur presynaptically and center on the synaptic vesicle cycle. The major steps of the synaptic vesicle cycle were described 20-40 years ago by investigators using electrophysiology and electron microscopy (reviewed in refs. 1-3). In brief, neurons produce specialized vesicles that are transported down axons to synaptic sites, where they are filled with neurotransmitter and stored in clusters. A small fraction of the vesicles become docked at active zones on the presynaptic membrane. The arrival of an electrical signal at the synapse induces the opening of voltage-gated calcium channels, and the resulting influx of calcium leads to the fusion of some of the docked synaptic vesicles with the plasma membrane and the release of neurotransmitter into the synaptic cleft. Transmission of the chemical signal is completed when the neurotransmitter binds postsynaptic receptors. The cycle continues in the presynapse with the docking of additional vesicles and the local recycling of fused vesicle membrane by endocytosis. Over the past 15 years, a molecular description of the synaptic vesicle cycle has begun to emerge. Biochemical and molecular studies have been important for the identification and analysis of many presynaptic proteins (reviewed in refs. 4-6) and have illuminated the roles of some of these proteins in the synaptic vesicle cycle.Classical genetic approaches using invertebrates have complemented biochemical studies by identifying additional presynaptic components and by allowing assessment of the function and importance of individual proteins (7)(8)(9)(10)(11)(12) While it has been known for some time that certain C. elegans uncoordinated (Unc) mutants are resistant to AChE inhibitors (13-17), the use of genetic screens to select for Ric mutants directly has thus far resulted in the isolation of mutations in only 6 genes (13,18 4These studies were begun while A

Mitochondrial disorders, characterized by clinical symptoms and/or OXPHOS deficiencies, are caused by pathogenic variants in mitochondrial genes. However, pathogenic variants in some of these genes can lead to clinical manifestations which overlap with other neuromuscular diseases, which can be caused by pathogenic variants in non-mitochondrial genes as well. Mitochondrial pathogenic variants can be found in the mitochondrial DNA (mtDNA) or in any of the 1,500 nuclear genes with a mitochondrial function. We have performed a two-step next-generation sequencing approach in a cohort of 117 patients, mostly children, in whom a mitochondrial disease-cause could likely or possibly explain the phenotype. A total of 86 patients had a mitochondrial disorder, according to established clinical and biochemical criteria. The other 31 patients had neuromuscular symptoms, where in a minority a mitochondrial genetic cause is present, but a non-mitochondrial genetic cause is more likely. All patients were screened for pathogenic variants in the mtDNA and, if excluded, analyzed by whole exome sequencing (WES). Variants were filtered for being pathogenic and compatible with an autosomal or X-linked recessive mode of inheritance in families with multiple affected siblings and/or consanguineous parents. Non-consanguineous families with a single patient were additionally screened for autosomal and X-linked dominant mutations in a predefined gene-set. We identified causative pathogenic variants in the mtDNA in 20% of the patient-cohort, and in nuclear genes in 49%, implying an overall yield of 68%. We identified pathogenic variants in mitochondrial and non-mitochondrial genes in both groups with, obviously, a higher number of mitochondrial genes affected in mitochondrial disease patients. Furthermore, we show that 31% of the disease-causing genes in the mitochondrial patient group were not included in the MitoCarta database, and therefore would have been missed with MitoCarta based gene-panels. We conclude that WES is preferable to panel-based approaches for both groups of patients, as the mitochondrial gene-list is not complete and mitochondrial symptoms can be secondary. Also, clinically and genetically heterogeneous disorders would require sequential use of multiple different gene panels. We conclude that WES is a comprehensive and unbiased approach to establish a genetic diagnosis in these patients, able to resolve multi-genic disease-causes.

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We characterized 18 genes from Caenorhabditis elegans that, when mutated, confer recessive resistance to inhibitors of acetylcholinesterase. These include previously described genes as well as newly identified genes; they encode essential as well as nonessential functions. In the absence of acetylcholinesterase inhibitors, the different mutants display a wide range of behavioral deficits, from mild uncoordination to almost complete paralysis. Measurements of acetylcholine levels in these mutants suggest that some of the genes are involved in presynaptic functions.

BackgroundIn South East Asia, concerns exist about the acceptability of peanut-based Ready-to-Use-Therapeutic-Foods (RUTF) for the treatment of severe acute malnutrition (SAM). Therefore, an alternative, culturally acceptable RUTF made from locally available ingredients and complying with local food traditions and preferences was developed. The current study evaluated its acceptability and impact on anthropometry.MethodsThe study was a randomized, two-arm, cross-over intervention trial to test the acceptability of the local product (bar) against a commercially available, peanut-based RUTF paste (Plumpy’nut®). Children (n = 67) from two kindergartens in a rural area of North Vietnam were recruited. The age of the children was between 3 and 5 years.ResultsThe Vietnamese RUTF was well-accepted, although overall acceptability was less than of Plumpy’nut®, with the latter scoring higher on palatability (P < 0.05). In contrast, reluctance to eat Plumpy’nut® was higher than for the Vietnamese RUTF (P < 0.05). Impact on anthropmetrical indices was similar for both RUTF. The nutritional status of the children who consumed the two RUTF over a 4 week period improved significantly, with a mean weight gain of 0.64 (SD 0.27) Kg, and increases in WHZ and HAZ z-scores of 0.48 (SD 0.30) and 0.05 (SD 0.13) respectively (P < 0.01 both). Weight gain was similar between the 2 products (0.32 kg per 2 weeks for both).ConclusionsBoth the commercial Plumpy’nut® and the local produced RUTF were accepted although the harder consistency of the local product might have caused the lower overall acceptance. The promising increase in nutritional status needs to be confirmed in a controlled trial in children with SAM.

Adding micronutrient powders (MNP) to complementary foods at the point of preparation (home fortification) can improve micronutrient status of young children. Ensuring sustained access to MNPs at scale, however, remains challenging in many countries. The Global Alliance for Improved Nutrition (GAIN) partnered with the National Institute of Nutrition (NIN) in Vietnam to pioneer the distribution of a locally-produced MNP, provided for sale through the public health system with counseling on optimal infant and young child feeding practices by trained health workers. Different packaging options were available to adapt to caregivers’ disposable income. During the six-month pilot, 1.5 million sachets were sold through 337 health centers across four provinces, targeting children 6–59 months of age. Sales were routinely monitored, and a cross-sectional survey in 32 communes for caregivers (n = 962) and health staff (n = 120) assessed MNP coverage and compliance, five months after the start of distribution. A total of 404 caregivers among the 962 caregivers surveyed (i.e., 42%) had visited the health center in the past year. Among them, 290 caregivers had heard about the product and a total of 217caregivers had given the MNP to their child at least once, representing a conversion rate from product awareness to product trial of 74.8%. The effective coverage (i.e., consumption of ≥3 sachets/child/week) was 11.5% among the total surveyed caregivers and reached 27.3% amongst caregivers who visited health centers in the previous month. The MNP purchase trends showed that the number of sachets bought by caregivers was positively correlated with the wealth index. The pilot showed that providing MNPs for sale in packs of various quantities, combined with infant and young child feeding (IYCF) counseling at the health center, is effective for groups accessing the health system.

Background & Aims Fibroblast Growth Factors (FGFs) promote the proliferation and survival of hepatic progenitor cells (HPCs) via AKT-dependent β-catenin activation. Moreover, the emergence of hepatocytes expressing the HPC marker A6 during 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced liver injury is mediated partly by FGF and β-catenin signaling. Herein, we investigate the role of FGF signaling and AKT-mediated β-catenin activation in acute DDC liver injury. Methods Transgenic mice were fed DDC chow for 14 days concurrent with either Fgf10 over-expression or inhibition of FGF signaling via expression of soluble dominant-negative FGF Receptor (R)-2IIIb. Results After 14 days of DDC treatment, there was an increase in periportal cells expressing FGFR1, FGFR2, and AKT-activated phospho-Serine 552 (pSer552) β-CATENIN in association with up-regulation of genes encoding FGFR2IIIb ligands, Fgf7, Fgf10, and Fgf22. In response to Fgf10 over-expression, there was an increase in the number of pSer552-β-CATENIN(positive)+ive periportal cells as well as cells co-positive for A6 and hepatocyte marker, Hepatocyte Nuclear Factor-4α (HNF4α). A similar expansion of A6+ive cells was observed after Fgf10 over-expression with regular chow and after partial hepatectomy during ethanol toxicity. Inhibition of FGF signaling increased the periportal A6+iveHNF4α+ive cell population while reducing centrolobular A6+ive HNF4α+ive cells. AKT inhibition with Wortmannin attenuated FGF10-mediated A6+iveHNF4α+ive cell expansion. In vitro analyses using FGF10 treated HepG2 cells demonstrated AKT-mediated β-CATENIN activation but not enhanced cell migration. Conclusion During acute DDC treatment, FGF signaling promotes the expansion of A6-expressing liver cells partly via AKT-dependent activation of β-CATENIN expansion of A6+ive periportal cells and possibly by reprogramming of centrolobular hepatocytes.