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BACKGROUND: Understanding genome organization and evolution is important for species involved in transmission of human diseases, such as mosquitoes. Anophelinae and Culicinae subfamilies of mosquitoes show striking differences in genome sizes, sex chromosome arrangements, behavior, and ability to transmit pathogens. However, the genomic basis of these differences is not fully understood. METHODS: In this study, we used a combination of advanced genome technologies such as Oxford Nanopore Technology sequencing, Hi-C scaffolding, Bionano, and cytogenetic mapping to develop an improved chromosome-scale genome assembly for the West Nile vector Culex quinquefasciatus. RESULTS: We then used this assembly to annotate odorant receptors, odorant binding proteins, and transposable elements. A genomic region containing male-specific sequences on chromosome 1 and a polymorphic inversion on chromosome 3 were identified in the Cx. quinquefasciatus genome. In addition, the genome of Cx. quinquefasciatus was compared with the genomes of other mosquitoes such as malaria vectors An. coluzzi and An. albimanus, and the vector of arboviruses Ae. aegypti. Our work confirms significant expansion of the two chemosensory gene families in Cx. quinquefasciatus, as well as a significant increase and relocation of the transposable elements in both Cx. quinquefasciatus and Ae. aegypti relative to the Anophelines. Phylogenetic analysis clarifies the divergence time between the mosquito species. Our study provides new insights into chromosomal evolution in mosquitoes and finds that the X chromosome of Anophelinae and the sex-determining chromosome 1 of Culicinae have a significantly higher rate of evolution than autosomes. CONCLUSION: The improved Cx. quinquefasciatus genome assembly uncovered new details of mosquito genome evolution and has the potential to speed up the development of novel vector control strategies.
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Aedes , Culex , Animales , Humanos , Masculino , Filogenia , Elementos Transponibles de ADN/genética , Mosquitos Vectores/genética , Culex/genética , Aedes/genética , Cromosomas , Evolución MolecularRESUMEN
Mosquitoes such as Aedes aegypti must consume a blood meal for the nutrients necessary for egg production. Several transcriptome and proteome changes occur post-blood meal that likely corresponds with codon usage alterations. Transfer RNA (tRNA) is the adapter molecule that reads messenger RNA codons to add the appropriate amino acid during protein synthesis. Chemical modifications to tRNA enhance codon decoding, improving the accuracy and efficiency of protein synthesis. Here, we examined tRNA modifications and transcripts associated with the blood meal and subsequent periods of vitellogenesis in A. aegypti. More specifically, we assessed tRNA transcript abundance and modification levels in the fat body at critical times post blood-feeding. Based on a combination of alternative codon usage and identification of particular modifications, we discovered that increased transcription of tyrosine tRNAs is likely critical during the synthesis of egg yolk proteins in the fat body following a blood meal. Altogether, changes in both the abundance and modification of tRNA are essential factors in the process of vitellogenin production after blood-feeding in mosquitoes.
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Liquid chromatography-tandem mass spectrometry (LC-MS/MS) has become the gold-standard technique to study RNA and its various modifications. While most research on RNA nucleosides has been focused on their biological roles, discovery of new modifications remains of interest. With state-of-the-art technology, the presence of artifacts can confound the identification of new modifications. Here, we report the characterization of a non-natural mcm5 isoC ribonucleoside in S. cerevisiae total tRNA hydrolysate by higher-energy collisional dissociation (HCD)-based fingerprints and isotope labeling of RNA. Its discovery revealed a class of amino/imino ribonucleoside artifacts that are generated during RNA hydrolysis under ammonium-buffered mild basic conditions. We then identified digestion conditions that can reduce or eliminate their formation. These finding and method enhancements will improve the accurate detection of new RNA modifications.
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Nucleósidos/química , ARN/análisis , Compuestos de Sulfhidrilo/química , Aminación , Cromatografía Líquida de Alta Presión , Hidrólisis , Marcaje Isotópico , ARN/metabolismo , ARN de Transferencia/química , ARN de Transferencia/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Espectrometría de Masas en TándemRESUMEN
While the use of RNA interference (RNAi) in molecular biology and functional genomics is a well-established technology, in vivo applications of synthetic short interfering RNAs (siRNAs) require chemical modifications. We recently found that amides as non-ionic replacements for phosphodiesters may be useful modifications for optimization of siRNAs. Herein, we report a comprehensive study of systematic replacement of a single phosphate with an amide linkage throughout the guide strand of siRNAs. The results show that amides are surprisingly well tolerated in the seed and central regions of the guide strand and increase the silencing activity when placed between nucleosides 10 and 12, at the catalytic site of Argonaute. A potential explanation is provided by the first crystal structure of an amide-modified RNA-DNA with Bacillus halodurans RNase H1. The structure reveals how small changes in both RNA and protein conformation allow the amide to establish hydrogen bonding interactions with the protein. Molecular dynamics simulations suggest that these alternative binding modes may compensate for interactions lost due to the absence of a phosphodiester moiety. Our results suggest that an amide can mimic important hydrogen bonding interactions with proteins required for RNAi activity and may be a promising modification for optimization of biological properties of siRNAs.
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Amidas/química , Fosfatos/química , ARN Interferente Pequeño/química , Ribonucleasa H/química , Amidas/metabolismo , Secuencia de Bases , Cristalografía por Rayos X , Humanos , Simulación de Dinámica Molecular , Conformación de Ácido Nucleico , Fosfatos/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Interferencia de ARN , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Ribonucleasa H/metabolismoRESUMEN
Objectives The Edinburgh Postnatal Depression Scale (EPDS) identifies women with depressive symptoms in pregnancy. Our primary objective was to determine the prevalence of EPDS screen-positive women delivering on our no prenatal care (laborist) service and to compare these patients to private patients delivering with prenatal care. Methods Retrospective cohort analysis of EPDS scores during January 1, 2015 to June 18, 2015 was conducted. Scores ≥ 10 were considered at-risk. Results were analyzed as an aggregate and then as no prenatal care versus prenatal care. Characteristics for patients with at-risk scores (EPDS ≥ 10) versus low-risk scores (EPDS < 10) were quantified. Results Analysis occurred on 970 women. EPDS ≥ 10 occurred in 12.4% (n = 120/970). Positive EPDS score was 21.1% without prenatal care versus 10.9% with adequate prenatal care (P = 0.003). Maternal demographics and delivery characteristics were clinically similar in patients with prenatal care compared to no prenatal care. Private insurance was more common in patients with prenatal care compared to no prenatal care (23.5 versus 8.1%, P = 0.0001). However, analysis of patients with EPDS > 10 showed non-significant distributions of ethnicity, private insurance, Medicaid, or no insurance compared to patients with EPDS < 10. Conclusion for Practice Patients without prenatal care who arrive solely for urgent "drop-in" delivery have a measurable increased risk factor for postpartum depressive symptoms. Ethnicity and payor status were related to adequacy of prenatal care but were not significant variables when analyzing patients with EPDS > 10. Laborist services providing care to "drop-in" patients should recognize this increased risk and develop policies for screening, referral and follow-up of at-risk patients.
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Depresión Posparto/diagnóstico , Atención Prenatal/normas , Adulto , Depresión Posparto/psicología , Femenino , Humanos , Tamizaje Masivo/métodos , Embarazo , Atención Prenatal/estadística & datos numéricos , Prevalencia , Escalas de Valoración Psiquiátrica , Psicometría/instrumentación , Psicometría/métodos , Estudios Retrospectivos , Factores de Riesgo , Encuestas y CuestionariosRESUMEN
BACKGROUND: Recent evidence suggests that exposure to intrauterine inflammation causes acute fetal brain injury and is linked to a spectrum of neurobehavioral disorders. In a rodent model of intrauterine inflammation induced by lipopolysaccharide (LPS) exposure in utero, activated microglia can be detected in the hippocampus of offspring survivors, as late as 60 days postnatal (DPN). Given that the hippocampus is important for learning and memory, these results suggest that in utero inflammation underlies long-term cognitive deficits observed in children/survivors. METHODS: An established mouse model of LPS-induced intrauterine inflammation was used to study hippocampal function from offspring at 44-59 DPN. Microgliosis was examined at 45 DPN. Extracellular field recordings of synaptic transmission were performed on acute hippocampal slices. RESULTS: LPS offspring mice displayed persistent microglial activation and increased CA3-CA1 excitatory synaptic strength, which can be explained in part by an increase in the probability of glutamate release, and reduced long-term synaptic potentiation compared to control mice. CONCLUSIONS: These results offer a mechanistic explanation for the cognitive and behavioral deficits observed in survivors of preterm birth caused by intrauterine inflammation.
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Modelos Animales de Enfermedad , Hipocampo/fisiología , Efectos Tardíos de la Exposición Prenatal/metabolismo , Transmisión Sináptica/fisiología , Útero/metabolismo , Animales , Femenino , Hipocampo/efectos de los fármacos , Inflamación/inducido químicamente , Inflamación/metabolismo , Lipopolisacáridos/toxicidad , Potenciación a Largo Plazo/efectos de los fármacos , Potenciación a Largo Plazo/fisiología , Masculino , Ratones , Técnicas de Cultivo de Órganos , Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Sobrevivientes , Transmisión Sináptica/efectos de los fármacos , Útero/efectos de los fármacos , Útero/patologíaRESUMEN
INTRODUCTION: Radiofrequency ablation (RFA) is a recommended curative intent treatment option for patients with early stage hepatocellular carcinoma (HCC). We investigated if wait times for RFA were associated with residual tumor, tumor recurrence, need for liver transplantation, or death. MATERIAL AND METHODS: We conducted a retrospective study of patients diagnosed with HCC between January 2010 and December 2013 presenting to University Health Network (UHN) in Toronto, Canada. All patients receiving curative intent RFA for HCC were included. Multivariable Cox regression was used to determine if wait times were associated with clinical outcomes. RESULTS: 219 patients were included in the study. 72.6% were male and the median age was 62.7 years (IQR 55.6-71). Median tumor size at diagnosis was 21.5 mm (IQR 17-26); median MELD was 8.7 (IQR 7.2-11.4) and 57.1% were Barcelona stage 0. The cause of liver disease was viral hepatitis in 73.5% (Hepatitis B and C). The median time from HCC diagnosis to RFA treatment was 96 days (IQR 75-139). In multivariate analysis, wait time was not associated with requiring liver transplant or tumor recurrence, however, each incremental 30-day wait time was associated with an increased risk of residual tumor (HR = 1.09; 95% CI 1.01-1.19; p = 0.033) as well as death (HR = 1.23; 95% CI 1.11-1.36; p ≤ 0.001). CONCLUSION: Incremental 30-day wait times are associated with a 9% increased risk of residual tumor and a 23% increased risk of death. We have identified system gaps where quality improvement measures can be implemented to reduce wait times and allocate resources for future RFA treatment, which may improve both quality and efficiency of HCC care.
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Carcinoma Hepatocelular/cirugía , Ablación por Catéter/mortalidad , Neoplasias Hepáticas/cirugía , Tiempo de Tratamiento , Listas de Espera/mortalidad , Anciano , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Ablación por Catéter/efectos adversos , Distribución de Chi-Cuadrado , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Ontario , Modelos de Riesgos Proporcionales , Mejoramiento de la Calidad , Indicadores de Calidad de la Atención de Salud , Estudios Retrospectivos , Factores de Riesgo , Factores de TiempoRESUMEN
Heat shock protein 70.3 (Hsp70.3) expression increases in response to cellular stress and plays a cytoprotective role. We have previously shown that Hsp70.3 expression is controlled through coordinated post-transcriptional regulation by miRNAs and alternative polyadenylation (APA), and APA-mediated shortening of the Hsp70.3 3'-UTR facilitates increased protein expression. A stress-induced increase in Hsp70.3 mRNA and protein expression is accompanied by alternative polyadenylation (APA)-mediated truncation of the 3'UTR of the Hsp70.3 mRNA transcript. However, the role that APA plays in stress-induced expression of Hsp70.3 remains unclear. Our results show that APA-mediated truncation of the Hsp70.3 3'UTR increases protein expression through enhanced polyribosome loading. Additionally, we demonstrate that the RNA binding protein HuR, which has been previously shown to play a role in mediating APA, is necessary for heat shock mediated increase in Hsp70.3 mRNA and protein. However, it is somewhat surprising to note that HuR does not play a role in APA of the Hsp70.3 mRNA, and these two regulatory events appear to be mutually exclusive regulators of Hsp70.3 expression. These results not only provide important insight to the regulation of stress response genes following heat shock, but also contribute an enhanced understanding of how alternative polyadenylation contributes to gene regulation.
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Proteínas ELAV/genética , Proteínas HSP70 de Choque Térmico/biosíntesis , Poliadenilación/genética , Biosíntesis de Proteínas , Regiones no Traducidas 3' , Animales , Proteínas ELAV/metabolismo , Regulación de la Expresión Génica , Proteínas HSP70 de Choque Térmico/genética , Respuesta al Choque Térmico/genética , Ratones , MicroARNs/genética , Procesamiento Proteico-Postraduccional/genética , ARN Mensajero/biosíntesis , ARN Mensajero/genéticaRESUMEN
Patients with KCNK9 imprinting syndrome demonstrate congenital hypotonia, variable cleft palate, normal MRIs and EEGs, delayed development, and feeding problems. Associated facial dysmorphic features include dolichocephaly with bitemporal narrowing, short philtrum, tented upper lip, palatal abnormalities, and small mandible. This disorder maps to chromosomal region 8q24, and it is caused by a specific missense mutation 770G>A in exon 2, replacing glycine at position 236 by arginine (G236R) in the maternal copy of KCNK9 within this locus. KCNK9 (also called TASK3) encodes a member of the two pore- domain potassium channel (K2P) subfamily. This gene is normally imprinted with paternal silencing, thus a mutation in the maternal copy of the gene will result in disease, whereas a mutation in the paternal copy will have no effect. Exome sequencing in four new patients with developmental delay and central hypotonia revealed de novo G236R mutations. Older members of a previously reported Arab-Israeli family have intellectual disability of variable severity, persistent feeding difficulties in infancy with dysphagia of liquids and dysphonia with a muffled voice in early adulthood, generalized hypotonia, weakness of proximal muscles, elongated face with narrow bitemporal diameter, and reduced facial movements. We describe the clinical features in four recently recognized younger patients and compare them with those found in members of the originally reported Arab-Israeli family and suggest this may be a treatable disorder. © 2016 Wiley Periodicals, Inc.
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Enfermedades Genéticas Congénitas/diagnóstico , Enfermedades Genéticas Congénitas/genética , Impresión Genómica , Canales de Potasio de Dominio Poro en Tándem/genética , Facies , Femenino , Enfermedades Genéticas Congénitas/terapia , Humanos , Lactante , Masculino , Mutación , FenotipoRESUMEN
Female ticks deposit large egg clusters that range in size from hundreds to thousands. These clusters are restricted to a deposition site, usually under leaf litter and other debris. These sites can be exposed to periodic flooding, where the cluster of tick eggs can float to the surface or remain underneath organic debris entirely underwater. Here, we examined the viability of egg clusters from winter ticks, Dermacentor albipictus , and lone star ticks, Amblyomma americanum , when partially submerged or fully submerged in water in relation to the developmental stages of the eggs. In general, egg clusters that were older and partially submerged had a higher viability than fully submerged, young eggs in water. A. americanum was much more resistant to water exposure between the two species. These studies highlight that egg clusters for specific tick species can remain viable when exposed to water for at least two weeks, where eggs float on the surface. These studies also suggest that water-based distribution of egg clusters could occur for some species, and flooding will differentially impact tick egg survival based on the specific developmental stage of exposure and species.
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Cerebellar Purkinje cells (PCs) are particularly sensitive to cerebral ischemia, and decreased GABA(A) receptor function following injury is thought to contribute to PC sensitivity to ischemia-induced excitotoxicity. Here we examined the functional properties of the GABA(A) receptors that are spared following ischemia in cultured Purkinje cells from rat and in vivo ischemia in mouse. Using subunit-specific positive modulators of GABA(A) receptors, we observed that oxygen and glucose deprivation (OGD) and cardiac arrest-induced cerebral ischemia cause a decrease in sensitivity to the ß(2/3) -subunit-preferring compound, etomidate. However, sensitivity to propofol, a ß-subunit-acting compound that modulates ß(1-3) -subunits, was not affected by OGD. The α/γ-subunit-acting compounds, diazepam and zolpidem, were also unaffected by OGD. We performed single-cell reverse transcription-polymerase chain reaction on isolated PCs from acutely dissociated cerebellar tissue and observed that PCs expressed the ß(1) -subunit, contrary to previous reports examining GABA(A) receptor subunit expression in PCs. GABA(A) receptor ß(1) -subunit protein was also detected in cultured PCs by western blot and by immunohistochemistry in the adult mouse cerebellum and levels remained unaffected by ischemia. High concentrations of loreclezole (30 µm) inhibited PC GABA-mediated currents, as previously demonstrated with ß(1) -subunit-containing GABA(A) receptors expressed in heterologous systems. From our data we conclude that PCs express the ß(1) -subunit and that there is a greater contribution of ß(1) -subunit-containing GABA(A) receptors following OGD.
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Isquemia Encefálica/metabolismo , Oxígeno/metabolismo , Células de Purkinje/metabolismo , Receptores de GABA-A/metabolismo , Animales , Western Blotting , Modelos Animales de Enfermedad , Glucosa/deficiencia , Inmunohistoquímica , Masculino , Ratones , Técnicas de Placa-Clamp , Reacción en Cadena de la Polimerasa , Ratas , Ratas Sprague-DawleyRESUMEN
Glutathione (GSH) is an antioxidant in human cells that is utilized to prevent damage occurred by reactive oxygen species, free radicals, peroxides, lipid peroxides, and heavy metals. Due to its immunological role in tuberculosis (TB), GSH is hypothesized to play an important part in the immune response against M. tb infection. In fact, one of the hallmark structures of TB is granuloma formation, which involves many types of immune cells. T cells, specifically, are a major component and are involved in the release of cytokines and activation of macrophages. GSH also serves an important function in macrophages, natural killer cells, and T cells in modulating their activation, their metabolism, proper cytokine release, proper redox activity, and free radical levels. For patients with increased susceptibility, such as those with HIV and type 2 diabetes, the demand for higher GSH levels is increased. GSH acts as an important immunomodulatory antioxidant by stabilizing redox activity, shifting of cytokine profile toward Th1 type response, and enhancing T lymphocytes. This review compiles reports showing the benefits of GSH in improving the immune responses against M. tb infection and the use of GSH as an adjunctive therapy for TB.
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During embryogenesis the nascent Caenorhabditis elegans epidermis secretes an apical extracellular matrix (aECM) that serves as an external stabilizer, preventing deformation of the epidermis by mechanical forces exerted during morphogenesis. At present, the factors that contribute to aECM function are mostly unknown, including the aECM components themselves, their posttranslational regulators, and the pathways required for their secretion. Here we showed that two proteins previously linked to aECM function, SYM-3/FAM102A and SYM-4/WDR44, colocalize to intracellular and membrane-associated puncta and likely function in a complex. Proteomics experiments also suggested potential roles for SYM-3/FAM102A and SYM-4/WDR44 family proteins in intracellular trafficking. Nonetheless, we found no evidence to support a critical function for SYM-3 or SYM-4 in the apical deposition of two aECM components, NOAH-1 and FBN-1. Moreover, loss of a key splicing regulator of fbn-1, MEC-8/RBPMS2, had surprisingly little effect on the abundance or deposition of FBN-1. Using a focused screening approach, we identified 32 additional proteins that likely contribute to the structure and function of the embryonic aECM. We also characterized morphogenesis defects in embryos lacking mir-51 microRNA family members, which display a similar phenotype to mec-8; sym double mutants. Collectively, these findings add to our knowledge of factors controlling embryonic morphogenesis.
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Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Morfogénesis/genética , Matriz Extracelular/metabolismo , Desarrollo Embrionario/genéticaRESUMEN
During embryogenesis the nascent Caenorhabditis elegans epidermis secretes an apical extracellular matrix (aECM) that serves as an external stabilizer, preventing deformation of the epidermis by mechanical forces exerted during morphogenesis. We showed that two conserved proteins linked to this process, SYM-3/FAM102A and SYM-4/WDR44, colocalize to intracellular and membrane-associated puncta and likely function together in a complex. Proteomics data also suggested potential roles for FAM102A and WDR44 family proteins in intracellular trafficking, consistent with their localization patterns. Nonetheless, we found no evidence to support a clear function for SYM-3 or SYM-4 in the apical deposition of two aECM components, FBN-1 and NOAH. Surprisingly, loss of MEC-8/RBPMS2, a conserved splicing factor and regulator of fbn-1 , had little effect on the abundance or deposition of FBN-1 to the aECM. Using a focused screening approach, we identified 32 additional proteins that likely contribute to the structure and function of the embryonic aECM. Lastly, we examined morphogenesis defects in embryos lacking mir-51 microRNA family members, which display a related embryonic phenotype to mec-8; sym double mutants. Collectively, our findings add to our knowledge of pathways controlling embryonic morphogenesis. SUMMARY STATEMENT: We identify new proteins in apical ECM biology in C. elegans and provide evidence that SYM-3/FAM102A and SYM-4/WDR44 function together in trafficking but do not regulate apical ECM protein deposition.
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Mycobacterium avium (M. avium), a type of nontuberculous mycobacteria (NTM), poses a risk for pulmonary infections and disseminated infections in immunocompromised individuals. Conventional treatment consists of a 12-month regimen of the first-line antibiotics rifampicin and azithromycin. However, the treatment duration and low antibiotic tolerability present challenges in the treatment of M. avium infection. Furthermore, the emergence of multidrug-resistant mycobacterium strains prompts a need for novel treatments against M. avium infection. This study aims to test the efficacy of a novel antimicrobial peptide, cyclic [R4W4], alongside the first-line antibiotics azithromycin and rifampicin in reducing M. avium survival. Colony-forming unit (CFU) counts were assessed after treating M. avium cultures with varying concentrations of cyclic [R4W4] alone or in conjunction with azithromycin or rifampicin 3 h and 4 days post-treatment. M. avium growth was significantly reduced 4 days after cyclic [R4W4] single treatment. Additionally, cyclic [R4W4]-azithromycin and cyclic [R4W4]-rifampicin combination treatments at specific concentrations significantly reduced M. avium survival 3 h and 4 days post-treatment compared with single antibiotic treatment alone. These findings demonstrate cyclic [R4W4] as a potent treatment method against M. avium and provide insight into novel therapeutic approaches against mycobacterium infections.
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Climate change is leading to substantial global thermal changes, which are particularly pronounced in polar regions. Therefore, it is important to examine the impact of heat stress on the reproduction of polar terrestrial arthropods, specifically, how brief extreme events may alter survival. We observed that sublethal heat stress reduces male fecundity in an Antarctic mite, yielding females that produced fewer viable eggs. Females and males collected from microhabitats with high temperatures showed a similar reduction in fertility. This impact is temporary, as indicated by recovery of male fecundity following return to cooler, stable conditions. The diminished fecundity is likely due to a drastic reduction in the expression of male-associated factors that occur in tandem with a substantial increase in the expression of heat shock proteins. Cross-mating between mites from different sites confirmed that heat-exposed populations have impaired male fertility. However, the negative impacts are transient as the effect on fertility declines with recovery time under less stressful conditions. Modeling indicated that heat stress is likely to reduce population growth and that short bouts of non-lethal heat stress could have substantial reproductive effects on local populations of Antarctic arthropods.
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Calor Extremo , Ácaros , Femenino , Animales , Masculino , Regiones Antárticas , Fertilidad , Respuesta al Choque TérmicoRESUMEN
Glutathione (GSH) is an important intracellular antioxidant responsible for neutralizing reactive oxygen species (ROS). Our laboratory previously demonstrated that the oral administration of liposomal GSH improves immune function against mycobacterium infections in healthy patients along with patients with HIV and Type 2 diabetes. We aim to determine if the topical application of a glutathione-cyclodextrin nanoparticle complex (GSH-CD) confers a therapeutic effect against mycobacterium infections. In our study, healthy participants received either topical GSH-CD (n = 15) or placebo (n = 15) treatment. Subjects were sprayed four times twice a day for three days topically on the abdomen. Blood draws were collected prior to application, and at 1, 4, and 72 h post-initial topical application. GSH, malondialdehyde (MDA), and cytokine levels were assessed in the processed blood samples of study participants. Additionally, whole blood cultures from study participants were challenged with Mycobacterium avium (M. avium) infection in vitro to assess mycobacterium survival post-treatment. Topical GSH-CD treatment was observed to elevate GSH levels in peripheral blood mononuclear cells (PBMCs) and red blood cells and decrease MDA levels in PBMCs 72 h post-treatment. An increase in plasma IL-2, IFN-γ, IL-12p70, and TNF-α was observed at 72 h post-topical GSH-CD treatment. Enhanced mycobacterium clearance was observed at 4 h and 72 h post-topical GSH-CD treatment. Overall, topical GSH-CD treatment was associated with improved immune function against M. avium infection. The findings of this pilot study suggest GSH-cyclodextrin complex formulation can be used topically as a safe alternative mode of GSH delivery in the peripheral blood.
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Functional disruption of the medial temporal lobe-dependent networks is thought to underlie episodic memory deficits in aging and Alzheimer's disease. Previous studies revealed that the anterior medial temporal lobe is more vulnerable to pathological and neurodegenerative processes in Alzheimer's disease. In contrast, cognitive and structural imaging literature indicates posterior, as opposed to anterior, medial temporal lobe vulnerability in normal aging. However, the extent to which Alzheimer's and aging-related pathological processes relate to functional disruption of the medial temporal lobe-dependent brain networks is poorly understood. To address this knowledge gap, we examined functional connectivity alterations in the medial temporal lobe and its immediate functional neighbourhood-the Anterior-Temporal and Posterior-Medial brain networks-in normal agers, individuals with preclinical Alzheimer's disease and patients with Mild Cognitive Impairment or mild dementia due to Alzheimer's disease. In the Anterior-Temporal network and in the perirhinal cortex, in particular, we observed an inverted 'U-shaped' relationship between functional connectivity and Alzheimer's stage. According to our results, the preclinical phase of Alzheimer's disease is characterized by increased functional connectivity between the perirhinal cortex and other regions of the medial temporal lobe, as well as between the anterior medial temporal lobe and its one-hop neighbours in the Anterior-Temporal system. This effect is no longer present in symptomatic Alzheimer's disease. Instead, patients with symptomatic Alzheimer's disease displayed reduced hippocampal connectivity within the medial temporal lobe as well as hypoconnectivity within the Posterior-Medial system. For normal aging, our results led to three main conclusions: (i) intra-network connectivity of both the Anterior-Temporal and Posterior-Medial networks declines with age; (ii) the anterior and posterior segments of the medial temporal lobe become increasingly decoupled from each other with advancing age; and (iii) the posterior subregions of the medial temporal lobe, especially the parahippocampal cortex, are more vulnerable to age-associated loss of function than their anterior counterparts. Together, the current results highlight evolving medial temporal lobe dysfunction in Alzheimer's disease and indicate different neurobiological mechanisms of the medial temporal lobe network disruption in aging versus Alzheimer's disease.
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Functional disruption of the medial temporal lobe-dependent networks is thought to underlie episodic memory deficits in aging and Alzheimer's disease. Previous studies revealed that the anterior medial temporal lobe is more vulnerable to pathological and neurodegenerative processes in Alzheimer's disease. In contrast, cognitive and structural imaging literature indicates posterior, as opposed to anterior, medial temporal lobe vulnerability in normal aging. However, the extent to which Alzheimer's and aging-related pathological processes relate to functional disruption of the medial temporal lobe-dependent brain networks is poorly understood. To address this knowledge gap, we examined functional connectivity alterations in the medial temporal lobe and its immediate functional neighborhood - the Anterior-Temporal and Posterior-Medial brain networks - in normal agers, individuals with preclinical Alzheimer's disease, and patients with Mild Cognitive Impairment or mild dementia due to Alzheimer's disease. In the Anterior-Temporal network and in the perirhinal cortex, in particular, we observed an inverted 'U-shaped' relationship between functional connectivity and Alzheimer's stage. According to our results, the preclinical phase of Alzheimer's disease is characterized by increased functional connectivity between the perirhinal cortex and other regions of the medial temporal lobe, as well as between the anterior medial temporal lobe and its one-hop neighbors in the Anterior-Temporal system. This effect is no longer present in symptomatic Alzheimer's disease. Instead, patients with symptomatic Alzheimer's disease displayed reduced hippocampal connectivity within the medial temporal lobe as well as hypoconnectivity within the Posterior-Medial system. For normal aging, our results led to three main conclusions: (1) intra-network connectivity of both the Anterior-Temporal and Posterior-Medial networks declines with age; (2) the anterior and posterior segments of the medial temporal lobe become increasingly decoupled from each other with advancing age; and, (3) the posterior subregions of the medial temporal lobe, especially the parahippocampal cortex, are more vulnerable to age-associated loss of function than their anterior counterparts. Together, the current results highlight evolving medial temporal lobe dysfunction in Alzheimer's disease and indicate different neurobiological mechanisms of the medial temporal lobe network disruption in aging vs. Alzheimer's disease.
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BACKGROUND: Extrapulmonary tuberculosis (EPTB) accounts for a fifth of all Mycobacterium tuberculosis (M. tb) infections worldwide. The rise of multidrug resistance in M. tb alongside the hepatotoxicity associated with antibiotics presents challenges in managing and treating tuberculosis (TB), thereby prompting a need for new therapeutic approaches. Administration of liposomal glutathione (L-GSH) has previously been shown to lower oxidative stress, enhance a granulomatous response, and reduce the burden of M. tb in the lungs of M. tb-infected mice. However, the effects of L-GSH supplementation during active EPTB in the liver and spleen have yet to be explored. METHODS: In this study, we evaluated hepatic glutathione (GSH) and malondialdehyde (MDA) levels, and the cytokine profiles of untreated and L-GSH-treated M. tb-infected wild type (WT) mice. Additionally, the hepatic and splenic M. tb burdens and tissue pathologies were also assessed. RESULTS: L-GSH supplementation increased total hepatic levels and reduced GSH. A decrease in the levels of MDA, oxidized GSH, and interleukin (IL)-6 was also detected following L-GSH treatment. Furthermore, L-GSH supplementation was observed to increase interferon-gamma (IFN-γ) and tumor necrosis factor (TNF)-α production and decrease IL-10 levels. M. tb survival was significantly reduced in the liver and spleen following L-GSH supplementation. L-GSH treatment also provided a host-protective effect in the liver and spleen of M. tb-infected mice. CONCLUSIONS: Overall, L-GSH supplementation elevated the levels of total and reduced forms of GSH in the liver and reduced the burden of M. tb by decreasing oxidative stress, enhancing the production of immunosupportive cytokines, and reducing the levels of immunosuppressive cytokines. These observed benefits highlight the potential of L-GSH supplementation during active EPTB and provide insight into novel therapeutic interventions against M. tb infections.