230 research outputs found
Envisioning a Decolonial Digital Mental Health
The field of digital mental health is making strides in the application
of technology to broaden access to care. We critically examine how
these technology-mediated forms of care might amplify historical
injustices, and erase minoritized experiences and expressions of
mental distress and illness. We draw on decolonial thought and critiques of identity-based algorithmic bias to analyze the underlying
power relations impacting digital mental health technologies today,
and envision new pathways towards a decolonial digital mental
health. We argue that a decolonial digital mental health is one that
centers lived experience over rigid classification, is conscious of
structural factors that infuence mental wellbeing, and is fundamentally designed to deter the creation of power differentials that
prevent people from having agency over their care. Stemming from
this vision, we make recommendations for how researchers and designers can support more equitable futures for people experiencing
mental distress and illness
Ascorbic Acid is an Abettor in Calcium Urolithiasis: An Experimental Study
Two sets of animal experiments using guinea pigs were planned to evaluate the effect of ascorbic acid supplementation on the lithogenic process. In the first set of experiments, 10, 40, and 60 mg doses of ascorbic acid/100g body weight/day were given for 105 days. Neither of the ascorbic acid doses given induced crystalluria, calcification or stone formation, thereby confirming our previous findings that ascorbic acid in the doses used by clinicians does not cause urolith formation. In the second set of experiments, ascorbic acid was supplemented in hypercalciuric (induced by calcium carbonate feeding) and hyperoxaluric (induced by sodium oxalate feeding) animals for 45 days. The results indicated that it exacerbated the calcification process in renal and bladder tissue
A Drosophila functional evaluation of candidates from human genome-wide association studies of type 2 diabetes and related metabolic traits identifies tissue-specific roles for dHHEX
BACKGROUND: Genome-wide association studies (GWAS) identify regions of the genome that are associated with particular traits, but do not typically identify specific causative genetic elements. For example, while a large number of single nucleotide polymorphisms associated with type 2 diabetes (T2D) and related traits have been identified by human GWAS, only a few genes have functional evidence to support or to rule out a role in cellular metabolism or dietary interactions. Here, we use a recently developed Drosophila model in which high-sucrose feeding induces phenotypes similar to T2D to assess orthologs of human GWAS-identified candidate genes for risk of T2D and related traits. RESULTS: Disrupting orthologs of certain T2D candidate genes (HHEX, THADA, PPARG, KCNJ11) led to sucrose-dependent toxicity. Tissue-specific knockdown of the HHEX ortholog dHHEX (CG7056) directed metabolic defects and enhanced lethality; for example, fat-body-specific loss of dHHEX led to increased hemolymph glucose and reduced insulin sensitivity. CONCLUSION: Candidate genes identified in human genetic studies of metabolic traits can be prioritized and functionally characterized using a simple Drosophila approach. To our knowledge, this is the first large-scale effort to study the functional interaction between GWAS-identified candidate genes and an environmental risk factor such as diet in a model organism system
Pparg-P465L Mutation Worsens Hyperglycemia in Ins2-Akita Female Mice via Adipose-Specific Insulin Resistance and Storage Dysfunction
OBJECTIVEThe dominant-negative P467L mutation in peroxisome proliferator activated receptor-γ (PPARγ) was identified in insulin-resistant patients with hyperglycemia and lipodystrophy. In contrast, mice carrying the corresponding Pparg-P465L mutation have normal insulin sensitivity, with mild hyperinsulinemia. We hypothesized that murine Pparg-P465L mutation leads to covert insulin resistance, which is masked by hyperinsulinemia and increased pancreatic islet mass, to retain normal plasma glucose.RESEARCH DESIGN AND METHODSWe introduced in PpargP465L/+ mice an Ins2-Akita mutation that causes improper protein folding and islet apoptosis to lower plasma insulin.RESULTSUnlike Ins2Akita/+ littermates, male PpargP465L/+Ins2Akita/+ mice have drastically reduced life span with enhanced type 1 diabetes. Hyperglycemia in Ins2Akita/+ females is mild. However, PpargP465L/+Ins2Akita/+ females have aggravated hyperglycemia, smaller islets, and reduced plasma insulin. In an insulin tolerance test, they showed smaller reduction in plasma glucose, indicating impaired insulin sensitivity. Although gluconeogenesis is enhanced in PpargP465L/+Ins2Akita/+ mice compared with Ins2Akita/+, exogenous insulin equally suppressed gluconeogenesis in hepatocytes, suggesting that PpargP465L/+Ins2Akita/+ livers are insulin sensitive. Expression of genes regulating insulin sensitivity and glycogen and triglyceride contents suggest that skeletal muscles are equally insulin sensitive. In contrast, adipose tissue and isolated adipocytes from PpargP465L/+Ins2Akita/+ mice have impaired glucose uptake in response to exogenous insulin. PpargP465L/+Ins2Akita/+ mice have smaller fat depots composed of larger adipocytes, suggesting impaired lipid storage with subsequent hepatomegaly and hypertriglyceridemia.CONCLUSIONSPPARg-P465L mutation worsens hyperglycemia in Ins2Akita/+ mice primarily because of adipose-specific insulin resistance and altered storage function. This underscores the important interplay between insulin and PPARγ in adipose tissues in diabetes
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Further evidence for the involvement of EFL1 in a Shwachman-Diamond-like syndrome and expansion of the phenotypic features.
Recent evidence has implicated EFL1 in a phenotype overlapping Shwachman-Diamond syndrome (SDS), with the functional interplay between EFL1 and the previously known causative gene SBDS accounting for the similarity in clinical features. Relatively little is known about the phenotypes associated with pathogenic variants in the EFL1 gene, but the initial indication was that phenotypes may be more severe, when compared with SDS. We report a pediatric patient who presented with a metaphyseal dysplasia and was found to have biallelic variants in EFL1 on reanalysis of trio whole-exome sequencing data. The variant had not been initially reported because of the research laboratory's focus on de novo variants. Subsequent phenotyping revealed variability in her manifestations. Although her metaphyseal abnormalities were more severe than in the original reported cohort with EFL1 variants, the bone marrow abnormalities were generally mild, and there was equivocal evidence for pancreatic insufficiency. Despite the limited number of reported patients, variants in EFL1 appear to cause a broader spectrum of symptoms that overlap with those seen in SDS. Our report adds to the evidence of EFL1 being associated with an SDS-like phenotype and provides information adding to our understanding of the phenotypic variability of this disorder. Our report also highlights the value of exome data reanalysis when a diagnosis is not initially apparent
Pro- and Antiatherogenic Effects of a Dominant-Negative P465L Mutation of Peroxisome Proliferator-Activated Receptor- in Apolipoprotein E-Null Mic
The dominant-negative mutation, P467L, in Peroxisome Proliferator Activated Receptor gamma (PPARγ) affects adipose tissue distribution, insulin sensitivity and blood pressure in heterozygous humans. We hypothesized that the equivalent mutation, PPARγ-P465L, in mice will worsen atherosclerosis
Centrosomal kinase Nek2 Cooperates with Oncogenic Pathways to Promote Metastasis
Centrosomal kinase Nek2 is overexpressed in different cancers, yet how it contributes toward tumorigenesis remains poorly understood. dNek2 overexpression in a Drosophila melanogaster model led to upregulation of Drosophila Wnt ortholog wingless (Wg), and alteration of cell migration markers—Rho1, Rac1 and E-cadherin (Ecad)—resulting in changes in cell shape and tissue morphogenesis. dNek2 overexpression cooperated with receptor tyrosine kinase and mitogen-activated protein kinase signaling to upregulate activated Akt, Diap1, Mmp1 and Wg protein to promote local invasion, distant seeding and metastasis. In tumor cell injection assays, dNek2 cooperated with Ras and Src signaling to promote aggressive colonization of tumors into different adult fly tissues. Inhibition of the PI3K pathway suppressed the cooperation of dNek2 with other growth pathways. Consistent with our fly studies, overexpression of human Nek2 in A549 lung adenocarcinoma and HEK293T cells led to activation of the Akt pathway and increase in b-catenin protein levels. Our computational approach identified a class of Nek2-inhibitory compounds and a novel drug-like pharmacophore that reversed the Nek2 overexpression phenotypes in flies and human cells. Our finding posits a novel role for Nek2 in promoting metastasis in addition to its currently defined role in promoting chromosomal instability. It provides a rationale for the selective advantage of centrosome amplification in cancer
Assessment of the effect of phenytoin on cutaneous healing from excision of melanocytic nevi on the face and on the back
<p>Abstract</p> <p>Background</p> <p>Topical phenytoin is a powerful skin wounds healing and it may be useful in clinical practice. The purpose of this study was to evaluate the effect of topical phenytoin 0.5%, by comparing it with cream (control) in wounds resulting from excision of two melanocytic nevi in the same patient. Our purpose was also to assess if phenytoin had better therapeutic and cosmetic outcomes when compared with cream (control).</p> <p>Methods</p> <p>This study evaluated 100 patients with skin wounds from excision of melanocytic nevi. 50 patients with lesions on the face and 50 patients with lesions on the back, totalizing 200 lesions excised with modified punch. The resulting superficial skin wounds had the same diameter and depth, and second intention healing followed.</p> <p>Patients were followed for 60 days. Student's t-test, Mann Whitney nonparametric test, analysis of variance, LSD test, Shapiro-Wilks test and Fisher test were used to analyze the results, depending on the nature of the variables being studied.</p> <p>Results</p> <p>Phenytoin showed better therapeutic and cosmetic results, by healing faster, with more intense epithelization in wounds in comparison with cream (control). Phenytoin showed a statistically significant difference regarding the following parameters (p < 0.05): wounded area and healing time. Phenytoin application resulted in a smaller area and a shorter healing time. Also the intensity of exudates, bleeding, and the epithelization were more intense in phenytoin-treated wounds. Regarding the shape and thickness of the scar, injuries treated with phenytoin had round and flat shaped scars in most of the cases. Considering patient's gender and phototype, female patients presented smaller wounds and scar areas; and phototype I had the largest scar areas. Contact eczema was an adverse reaction in 7 injuries located on the back caused by cream (control) and hypoallergenic tape.</p> <p>Conclusions</p> <p>Phenytoin showed better therapeutic and cosmetic results compared with cream (control). Phenytoin is a low cost drug, which accelerates skin wounds healing in human patients. Trial registration: ISRCTN96539803</p
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