RESUMEN
Study objectives were to determine the effects of mitoquinol (MitoQ, a mitochondrial-targeted antioxidant) on biomarkers of metabolism and inflammation during acute heat stress (HS). Crossbred barrows [nâ =â 32; 59.0â ±â 5.6 kg body weight (BW)] were blocked by BW and randomly assigned to 1 of 4 environmental-therapeutic treatments: 1) thermoneutral (TN) control (nâ =â 8; TNCon), 2) TN and MitoQ (nâ =â 8; TNMitoQ), 3) HS control (nâ =â 8; HSCon), or 4) HS and MitoQ (nâ =â 8; HSMitoQ). Pigs were acclimated for 6 d to individual pens before study initiation. The trial consisted of two experimental periods (P). During P1 (2 d), pigs were fed ad libitum and housed in TN conditions (20.6â ±â 0.8 °C). During P2 (24 h), HSCon and HSMitoQ pigs were exposed to continuous HS (35.2â ±â 0.2 °C), while TNCon and TNMitoQ remained in TN conditions. MitoQ (40 mg/d) was orally administered twice daily (0700 and 1800 hours) during P1 and P2. Pigs exposed to HS had increased rectal temperature, skin temperature, and respiration rate (+1.5 °C, +6.8 °C, and +101 breaths per minute, respectively; Pâ <â 0.01) compared to their TN counterparts. Acute HS markedly decreased feed intake (FI; 67%; Pâ <â 0.01); however, FI tended to be increased in HSMitoQ relative to HSCon pigs (1.5 kg vs. 0.9 kg, respectively; Pâ =â 0.08). Heat-stressed pigs lost BW compared to their TN counterparts (-4.7 kg vs. +1.6 kg, respectively; Pâ <â 0.01); however, the reduction in BW was attenuated in HSMitoQ compared to HSCon pigs (-3.9 kg vs. -5.5 kg, respectively; Pâ <â 0.01). Total gastrointestinal tract weight (empty tissue and luminal contents) was decreased in HS pigs relative to their TN counterparts (6.2 kg vs. 8.6 kg, respectively; Pâ <â 0.01). Blood glucose increased in HSMitoQ relative to HSCon pigs (15%; Pâ =â 0.04). Circulating non-esterified fatty acids (NEFA) increased in HS compared to TN pigs (Pâ <â 0.01), although this difference was disproportionately influenced by elevated NEFA in HSCon relative to HSMitoQ pigs (251 µEq/L vs. 142 µEq/L; Pâ <â 0.01). Heat-stressed pigs had decreased circulating insulin relative to their TN counterparts (47%; Pâ =â 0.04); however, the insulin:FI ratio tended to increase in HS relative to TN pigs (Pâ =â 0.09). Overall, circulating leukocytes were similar across treatments (Pâ >â 0.10). Plasma C-reactive protein remained similar among treatments; however, haptoglobin increased in HS relative to TN pigs (48%; Pâ =â 0.03). In conclusion, acute HS exposure negatively altered animal performance, inflammation, and metabolism, which were partially ameliorated by MitoQ.
Heat stress (HS) compromises animal health and productivity, and this causes major economic losses in almost every livestock sector. The negative consequences of HS are thought to originate from intestinal barrier dysfunction and subsequent immune activation. The underlying causes of lost intestinal integrity during HS are likely multifactorial; however, intestinal ischemia, increased accumulation of reactive oxygen species, and the ensuing epithelial oxidative damage might be potential causes. Mitochondria-targeted antioxidants, such as mitoquinol (MitoQ), are probably more effective than traditional dietary antioxidants (i.e., selenium, vitamin E) at alleviating oxidative stress, as they localize and accumulate within the mitochondria, potentiating their antioxidant activity. Thus, the present study aimed to investigate MitoQ's role during a thermal event in growing pigs. Herein, HS increased all body temperature indices, decreased feed intake (FI), and induced substantial body weight (BW) loss. Interestingly, the reduction in FI and BW was less dramatic in pigs receiving MitoQ. Changes in circulating metabolism and the acute phase response were observed due to the HS challenge; however, contrary to our expectations, these changes were not offset by MitoQ administration. Although our results suggest a positive MitoQ effect on growth performance, future studies are needed to corroborate the replicability of this response during HS.
Asunto(s)
Ubiquinona , Animales , Ubiquinona/análogos & derivados , Ubiquinona/farmacología , Ubiquinona/administración & dosificación , Masculino , Porcinos , Compuestos Organofosforados/farmacología , Compuestos Organofosforados/administración & dosificación , Antioxidantes/farmacología , Calor/efectos adversos , Respuesta al Choque Térmico/efectos de los fármacos , Enfermedades de los Porcinos/tratamiento farmacológico , Trastornos de Estrés por Calor/veterinaria , Trastornos de Estrés por Calor/tratamiento farmacológico , Distribución Aleatoria , Temperatura Corporal/efectos de los fármacosRESUMEN
No clear consensus has emerged from the literature on the gene expression changes that occur in human whole blood with age. In this study we compared whole blood ageing genes from the published literature with data on gene specificity for leukocyte subtypes. Surprisingly we found that highly ranked ageing genes were predominantly expressed by naïve T cells, with limited expression from more common cell types. Highly ranked ageing genes were also more likely to have decreased expression with age. Taken together, it is plausible that much of the observed gene expression changes in whole blood is reflecting the decline in abundance of naïve T cells known to occur with age, rather than changes in transcription rates in common cell types. Correct attribution of the gene expression changes that occur with age is essential for understanding the underlying mechanisms.
RESUMEN
The oocyte expresses certain genes during folliculogenesis to regulate the acquisition of oocyte competence. Oocyte competence, or oocyte quality, is directly related to the ability of the oocyte to result in a successful pregnancy following fertilization. Presently, approximately 40 % of bovine embryos will develop to the blastocyst stage in vitro. Characterization of factors regulating these processes is crucial to improve the efficiency of bovine in vitro embryo production. We demonstrated that the secreted protein, agouti-signaling protein (ASIP) is highly abundant in the bovine oocyte and aimed to characterize its spatiotemporal expression profile in the ovary and throughout early embryonic development. In addition to oocyte expression, ASIP was detected in granulosa, cumulus, and theca cells isolated from antral follicles. Both gene expression data and immunofluorescent staining indicated ASIP declines with oocyte maturation which may indicate a potential role for ASIP in the attainment of oocyte competence. Microinjection of zygotes using small interfering RNA targeting ASIP led to a 16 % reduction in the rate of development to the blastocyst stage. Additionally, we examined potential ASIP signaling mechanisms through which ASIP may function to establish oocyte developmental competence. The expression of melanocortin receptor 3 and 4 and the coreceptor attractin was detected in the oocyte and follicular cells. The addition of cortisol during in vitro maturation was found to increase significantly oocyte ASIP levels. In conclusion, these results suggest a functional role for ASIP in promoting oocyte maturation and subsequent embryonic development, potentially through signaling mechanisms involving cortisol.
RESUMEN
Objective: To understand whether team member support reduces team leader stress. Method: In Phase 1, we used hierarchical linear modeling with survey data and administrative records from 45 Veterans Health Administration teams (73 providers and 228 associated members) to investigate how teamwork support mitigates leader stress. In Phase 2, we adopted a parallel/simultaneous mixed methods design, utilizing open- and closed-ended responses from 267 additional Veterans Health Administration providers. With the mixed methods design we first analyzed open-ended responses using directed content analysis and hypothesis coding. Next, we transformed our codes into counts and compared them with closed-ended responses to understand whether teamwork support allows leaders to engage in work aligned with their qualifications. Results: As predicted, providers' role conflict corresponded with decreased performance under low teamwork support, but this negative relationship was attenuated with high teamwork support as such support allows leaders to focus on tasks they are uniquely qualified to perform. Conclusions: These findings emphasize the facilitative nature of teams in supporting leaders: followers provide teamwork support that helps leaders navigate role conflict by allowing leaders to work on tasks consistent with their qualifications.
RESUMEN
The neural connectivity among the oral cavity, pharynx, and esophagus is a critical component of infant feeding physiology. Central integration of oral and pharyngeal afferents alters motor outputs to structures that power swallowing, but the potential effects of esophageal afferents on preesophageal feeding physiology are unclear. These effects may explain the prevalence of oropharyngeal dysphagia in infants suffering from gastroesophageal reflux (GER), though the mechanism underlying this relationship remains unknown. Here we use the validated infant pig model to assess the impacts of simulated GER on preesophageal feeding parameters. We used high-speed videofluoroscopy and electromyography to record bottle-feeding before and following the infusion of a capsaicin-containing solution into the lower esophagus. Sucking parameters were minimally affected by capsaicin exposure, such that genioglossus activity was unchanged and tongue kinematics were largely unaffected. Aspects of the pharyngeal swallow were altered with simulated GER, including increased thyrohyoid muscle activity, increased excursions of the hyoid and thyroid per swallow, decreased swallow frequency, and increased bolus sizes. These results suggest that esophageal afferents can elicit changes in pharyngeal swallowing. In addition, decreased swallowing frequency may be the mechanism by which esophageal pathologies induce oropharyngeal dysphagia. Although recent work indicates that oral or pharyngeal capsaicin may improve dysphagia symptoms, the decreased performance following esophageal capsaicin exposure highlights the importance of designing sensory interventions based upon neurophysiology and the mechanisms underlying disordered feeding. This mechanistic approach requires comprehensive data collection across the entirety of the feeding process, which can be achieved using models such as the infant pig.NEW & NOTEWORTHY Simulated gastroesophageal reflux (GER) in an infant pig model resulted in significant changes in pharyngeal swallowing, which suggests that esophageal afferents are centrally integrated to alter motor outputs to the pharynx. In addition, decreased swallow frequency and increased bolus sizes may be underlying mechanisms by which esophageal pathologies induce oropharyngeal dysphagia. The infant pig model used here allows for a mechanistic approach, which can facilitate the design of intervention strategies based on neurophysiology.
Asunto(s)
Capsaicina , Deglución , Reflujo Gastroesofágico , Animales , Reflujo Gastroesofágico/fisiopatología , Porcinos , Deglución/efectos de los fármacos , Capsaicina/farmacología , Esófago/fisiopatología , Esófago/efectos de los fármacos , Esófago/inervación , Electromiografía , Faringe/fisiopatología , Animales Recién Nacidos , Trastornos de Deglución/fisiopatología , Trastornos de Deglución/etiología , Orofaringe/fisiopatología , Alimentación con Biberón , Femenino , FluoroscopíaRESUMEN
The influence of systemic immune activation on whole-body calcium (Ca) trafficking and gastrointestinal tract (GIT) physiology is not clear. Thus, the study objectives were to characterize the effects of lipopolysaccharide (LPS) on Ca pools and GIT dynamics to increase understanding of immune-induced hypocalcemia, ileus, and stomach hemorrhaging. Twelve crossbred pigs [44â ±â 3 kg body weight (BW)] were randomly assigned to 1 of 2 intramuscular treatments: (1) control (CON; 2 mL saline; nâ =â 6) or (2) LPS (40 µg LPS/kg BW; nâ =â 6). Pigs were housed in metabolism stalls to collect total urine and feces for 6 h after treatment administration, at which point they were euthanized, and various tissues, organs, fluids, and digesta were weighed, and analyzed for Ca content. Data were analyzed with the MIXED procedure in SAS 9.4. Rectal temperature and respiration rate increased in LPS relative to CON pigs (1.4 °C and 32%, respectively; Pâ ≤â 0.05). Inflammatory biomarkers such as circulating alkaline phosphatase, aspartate aminotransferase, and total bilirubin increased in LPS compared with CON pigs whereas albumin decreased (Pâ ≤â 0.02). Plasma glucose and urea nitrogen decreased and increased, respectively, after LPS (43% and 80%, respectively; Pâ <â 0.01). Pigs administered LPS had reduced circulating ionized calcium (iCa) compared to CON (15%; Pâ <â 0.01). Considering estimations of total blood volume, LPS caused an iCa deficit of 23 mg relative to CON (Pâ <â 0.01). Adipose tissue and urine from LPS pigs had reduced Ca compared to CON (39% and 77%, respectively; Pâ ≤â 0.05). There did not appear to be increased Ca efflux into GIT contents and no detectable increases in other organ or tissue Ca concentrations were identified. Thus, while LPS caused hypocalcemia, we were unable to determine where circulating Ca was trafficked. LPS administration markedly altered GIT dynamics including stomach hemorrhaging, diarrhea (increased fecal output and moisture), and reduced small intestine and fecal pH (Pâ ≤â 0.06). Taken together, changes in GIT physiology suggested dyshomeostasis and alimentary pathology. Future research is required to fully elucidate the etiology of immune activation-induced hypocalcemia and GIT pathophysiology.
Lipopolysaccharide (LPS) activates the immune system and this is accompanied with hypocalcemia and altered gastrointestinal tract (GIT) physiology. The study objectives were to characterize whole-body calcium (Ca) trafficking and evaluate GIT dynamics during LPS-induced immune activation. Ca concentrations were analyzed after intramuscular LPS injection. Administering LPS caused marked alterations in metabolic and inflammatory biomarkers and GIT dynamics, characterized by increased lower GIT motility and stomach hemorrhaging. Circulating Ca and adipose tissue and urine Ca output were decreased after LPS. Ca concentrations in other tissues and GIT contents were not detectably different. Thus, we were unable to account for about 110 mg Ca following LPS. Where and how circulating Ca is partitioned during immune activation remains unclear.
Asunto(s)
Calcio , Tracto Gastrointestinal , Lipopolisacáridos , Animales , Femenino , Masculino , Calcio/metabolismo , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/metabolismo , Lipopolisacáridos/farmacología , Distribución Aleatoria , Porcinos , Enfermedades de los Porcinos/inducido químicamenteRESUMEN
Objectives were to examine the temporal pattern of intestinal mast cell dynamics and the effects of a mast cell stabilizer (ketotifen [Ket]) during acute heat stress (HS) in growing pigs. Crossbred barrows (nâ =â 42; 32.3â ±â 1.9 kg body weight [BW]) were randomly assigned to 1 of 7 environmental-therapeutic treatments: (1) thermoneutral (TN) control (TNCon; nâ =â 6), (2) 2 h HS control (2 h HSCon; nâ =â 6), (3) 2 h HSâ +â Ket (2 h HSKet; nâ =â 6); (4) 6 h HSCon (nâ =â 6), (5) 6 h HSKet (nâ =â 6), (6) 12 h HSCon (nâ =â 6), or (7) 12 h HSKet (nâ =â 6). Following 5 d of acclimation to individual pens, pigs were enrolled in two experimental periods (P). During P1 (3 d), pigs were housed in TN conditions (21.5â ±â 0.8 °C) for the collection of baseline measurements. During P2, TNCon pigs remained in TN conditions for 12 h, while HS pigs were exposed to constant HS (38.1â ±â 0.2 °C) for either 2, 6, or 12 h. Pigs were euthanized at the end of P2, and blood and tissue samples were collected. Regardless of time or therapeutic treatment, pigs exposed to HS had increased rectal temperature, skin temperature, and respiration rate compared to their TNCon counterparts (1.9 °C, 6.9° C, and 119 breaths/min; Pâ <â 0.01). As expected, feed intake and BW gain markedly decreased in HS pigs relative to their TNCon counterparts (Pâ <â 0.01). Irrespective of therapeutic treatment, circulating corticotropin-releasing factor decreased from 2 to 12 h of HS relative to TNCon pigs (Pâ <â 0.01). Blood cortisol increased at 2 h of HS (2-fold; Pâ =â 0.04) and returned to baseline by 6 h. Plasma histamine (a proxy of mast cell activation) remained similar across thermal treatments and was not affected by Ket administration (Pâ >â 0.54). Independent of Ket or time, HS increased mast cell numbers in the jejunum (94%; Pâ <â 0.01); however, no effects of HS on mast cell numbers were detected in the ileum or colon. Jejunum and ileum myeloperoxidase area remained similar among treatments (Pâ >â 0.58) but it tended to increase (12%; Pâ =â 0.08) in the colon in HSCon relative to TNCon pigs. Circulating lymphocytes and basophils decreased in HSKet relative to TN and HSCon pigs (Pâ ≤â 0.06). Blood monocytes and eosinophils were reduced in HS pigs relative to their TNCon counterparts (Pâ <â 0.01). In summary, HS increased jejunum mast cell numbers and altered leukocyte dynamics and proinflammatory biomarkers. However, Ket administration had no effects on mast cell dynamics measured herein.
Heat stress (HS) affects various physiological, metabolic, and endocrine parameters, ostensibly due to reduced intestinal barrier integrity and the ensuing immune response. Evidence indicates that generalized "stress" may be a critical component of HS-induced leaky gut, a mechanism likely mediated by mast cells. Mast cell activation has been extensively associated with various stress-related intestinal inflammatory conditions; however, its contribution to intestinal barrier dysfunction during HS remains unclear. Thus, this study was designed to evaluate mast cell dynamics during an acute HS challenge and to assess the effects a mast cell stabilizer on biomarkers of intestinal inflammation. Herein, HS induced a rapid increase in circulating cortisol, increased jejunum mast cell numbers, and altered metabolism, leukocyte dynamics, and proinflammatory biomarkers. Contrary to our hypothesis, HS did not alter circulating histamine (a biomarker of mast cell activation), and mast cell stabilization did not affect mast cell numbers nor altered histamine concentrations. Altogether, our observations support a connection between HS and intestinal mast cell infiltration that may contribute to the pathophysiology of intestinal dysfunction during a heat load.
Asunto(s)
Trastornos de Estrés por Calor , Enfermedades de los Porcinos , Porcinos , Animales , Dieta , Mastocitos , Respuesta al Choque Térmico , Temperatura Cutánea , Recto , Calor , Trastornos de Estrés por Calor/veterinariaRESUMEN
Rationale: Mycobacterium avium complex (MAC) is the most common cause of nontuberculous mycobacterial (NTM) pulmonary disease (PD), which exhibits increasing global incidence. Current microbiologic methods routinely used in clinical practice lack sensitivity and have long latencies, leading to delays in diagnosis and treatment initiation and evaluation. A clustered regularly interspaced short palindromic repeats (CRISPR)-based assay that measures MAC cell-free DNA (cfDNA) concentrations in serum could provide a rapid means to detect MAC infection and monitor response to antimicrobial treatment. Objectives: To develop and optimize a CRISPR MAC assay for MAC infection detection and to evaluate its diagnostic and prognostic performance in two MAC disease cohorts. Methods: MAC cfDNA serum concentrations were measured in individuals with diagnoses of MAC disease or who had bronchiectasis or chronic obstructive pulmonary disease diagnoses without histories of NTM PD or NTM-positive sputum cultures. Diagnostic performance was analyzed using pretreatment serum from two cohorts. Serum MAC cfDNA changes during MAC PD treatment were evaluated in a subset of patients with MAC PD who received macrolide-based multidrug regimens. Measurements and Main Results: The CRISPR MAC assay detected MAC cfDNA in MAC PD with 97.6% (91.6-99.7%) sensitivity and 97.6% (91.5-99.7%) specificity overall. Serum MAC cfDNA concentrations markedly decreased after MAC-directed treatment initiation in patients with MAC PD who demonstrated MAC culture conversion. Conclusions: This study provides preliminary evidence for the utility of a serum-based CRISPR MAC assay to rapidly detect MAC infection and monitor the response to treatment.
Asunto(s)
Ácidos Nucleicos Libres de Células , Complejo Mycobacterium avium , Infección por Mycobacterium avium-intracellulare , Humanos , Infección por Mycobacterium avium-intracellulare/diagnóstico , Infección por Mycobacterium avium-intracellulare/sangre , Infección por Mycobacterium avium-intracellulare/tratamiento farmacológico , Femenino , Masculino , Ácidos Nucleicos Libres de Células/sangre , Complejo Mycobacterium avium/genética , Complejo Mycobacterium avium/aislamiento & purificación , Anciano , Persona de Mediana Edad , ADN Bacteriano/sangre , ADN Bacteriano/análisis , Sensibilidad y Especificidad , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Estudios de Cohortes , Antibacterianos/uso terapéuticoRESUMEN
Functional decline with age contributes significantly to the burden of disease in developed countries. There is growing interest in the development of therapeutic interventions which slow or even reverse aging. Time and cost constraints prohibit the testing of a large number of interventions for health and lifespan extension in model organisms. Cell-based models of aging could enable high throughput testing of potential interventions. Despite extensive reports in the literature of cell properties that correlate with donor age, few are robustly observed across different laboratories. This casts doubt on the extent that aging signatures are captured in cultured cells. We tested molecular changes previously reported to correlate with donor age in peripheral blood mononuclear cells (PBMCs) and evaluated their suitability for inclusion in a panel of functional aging measures. The tested measures spanned several pathways implicated in aging including epigenetic changes, apoptosis, proteostasis, and intracellular communication. Surprisingly, only two markers correlated with donor age. DNA methylation age accurately predicted donor age confirming this is a robust aging biomarker. Additionally, the apoptotic marker CD95 correlated with donor age but only within subsets of PBMCs. To demonstrate cellular rejuvenation in response to a treatment will require integration of multiple read-outs of cell function. However, building a panel of measures to detect aging in cells is challenging and further research is needed to identify robust predictors of age in humans.
RESUMEN
There is a long-standing stigma associated with the use of epinephrine in digital nerve blocks (DNBs) over the concern of digital necrosis. We conducted a systematic review to assess the duration of anesthesia, onset of anesthesia, and complications of lidocaine with epinephrine compared with plain lidocaine for DNBs in adults. We searched Medline via Ovid, Cochrane Library, and ClinicalTrials.gov on January 28, 2020. We included randomized controlled trials that examined lidocaine with epinephrine 1:80,000 to 1:1,000,000 (1-12.5 µg/mL) and plain lidocaine for DNBs of fingers or toes in adults. We completed a blinded review of all unique articles, followed by full-text reviews, data extraction, and quality assessment of all eligible trials. Risk of bias was assessed to inform qualitative data analysis. We identified seven studies with a combined 363 adults and 442 DNBs that met the inclusion criteria. All five studies that reported duration of anesthesia established longer duration in the epinephrine-supplemented lidocaine group, with significant increases in three. Two of the three studies that reported the onset of anesthesia demonstrated significant differences. The two studies that reported complications did not have a single case of digital necrosis. In adults, the use of lidocaine with epinephrine 1:80,000 to 1:1,000,000 (1-12.5 µg/mL) for DNB yields a longer duration of anesthetic effect and seems to be as safe as plain lidocaine in healthy adults. Several studies had some concern for bias, and additional studies are warranted.
Asunto(s)
Lidocaína , Bloqueo Nervioso , Adulto , Humanos , Anestésicos Locales , Epinefrina , NecrosisRESUMEN
Objective: Obesity is a significant risk factor for adverse outcomes following coronavirus infection (COVID-19). However, BMI fails to capture differences in the body fat distribution, the critical driver of metabolic health. Conventional statistical methodologies lack functionality to investigate the causality between fat distribution and disease outcomes. Methods: We applied Bayesian network (BN) modelling to explore the mechanistic link between body fat deposition and hospitalisation risk in 459 participants with COVID-19 (395 non-hospitalised and 64 hospitalised). MRI-derived measures of visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and liver fat were included. Conditional probability queries were performed to estimate the probability of hospitalisation after fixing the value of specific network variables. Results: The probability of hospitalisation was 18% higher in people living with obesity than those with normal weight, with elevated VAT being the primary determinant of obesity-related risk. Across all BMI categories, elevated VAT and liver fat (>10%) were associated with a 39% mean increase in the probability of hospitalisation. Among those with normal weight, reducing liver fat content from >10% to <5% reduced hospitalisation risk by 29%. Conclusion: Body fat distribution is a critical determinant of COVID-19 hospitalisation risk. BN modelling and probabilistic inferences assist our understanding of the mechanistic associations between imaging-derived phenotypes and COVID-19 hospitalisation risk.
RESUMEN
Nares Strait, the waterway that separates northwest Greenland from Ellesmere Island, is a major pathway along which sea ice leaves the Arctic, including the planet's oldest and thickest sea ice that is experiencing an accelerated loss. Ice arches that develop during the winter at the Strait's northern or southern terminus can remain stable for months at a time during which the transport of sea ice ceases. The Arctic's most productive polynya, the North Water (NOW) or Pikialasorsuaq (West Greenlandic for 'great upwelling') forms at the Strait's southern end. There is evidence that a warming climate and the concomitant thinning of Arctic sea ice is weakening the arches and it has been proposed that this may impact the stability of NOW and the complex ecosystem that it sustains. Here we employ a categorization of recent winters with respect to the presence or absence of ice arches to explore their impact on sea ice along the Strait and over the NOW. We find that winters during which a southern ice arch is absent are associated with a reduced and thinner ice cover along the Strait with ice conditions over the NOW similar to that during winters with a southern arch. In winters, without a southern arch, there is also an acceleration of the winds along the Strait that contributes to the presence of reduced ice cover. Ocean color remote sensing data suggests that current levels of primary productivity over the NOW are independent of the presence or absence of an ice arch. The results suggest more research is needed to assess the stability of the NOW, with respect to reduced ice cover and primary productivity, in a future where ice arches cease to form along Nares Strait.
Asunto(s)
Ecosistema , Agua , Cubierta de Hielo , Clima , Estaciones del Año , Regiones ÁrticasRESUMEN
Rhesus macaques (Macaca mulatta) are amongst the most common nonhuman primate species used in biomedical research. These animals provide a precious resource for translational studies and opportunities to maximize rhesus data use are encouraged. Here we compile data produced from 10 years of investigator-driven pregnancy studies conducted at the Oregon National Primate Research Center (ONPRC). All pregnancies were generated within the consistent and reproducible protocols of the ONPRC time-mated breeding program. The data included are from control animals who did not experience in utero perturbations or experimental manipulations. A total of 86 pregnant rhesus macaques were delivered by cesarean section over a range of gestational days (G) 50 to G159 (where term is G165 ± 10 days in the rhesus macaque), with subsequent immediate tissue harvesting following standardized protocols. Fetal and placental growth measures, and all major organ weights are reported. All data are presented relative to gestational age for the entire cohort and in addition, data are stratified by fetal sex. The outcome is a large reference resource for use by laboratory animal researchers in future comparative fetal development studies.
Asunto(s)
Cesárea , Placenta , Embarazo , Animales , Femenino , Macaca mulatta , Desarrollo Fetal , Animales de LaboratorioRESUMEN
Despite decades of research, human cytomegalovirus (CMV) continues to contribute to significant morbidity and mortality in transplant settings and remains the leading cause of viral congenital infections. Clinical diagnosis of CMV infection and/or reactivation under these settings is completed using real time quantitative polymerase chain reaction (RT-qPCR). This assay performs well but is hampered by poor sensitivity and a lack of standardization among testing facilities. A point-of-care rapid diagnostic to determine CMV viremia could address these issues and improve patient care. In this manuscript, we introduce clustered regularly interspaced short palindromic repeats (CRISPR)-Cas12a technology to design and validate a rapid diagnostic for CMV. This system was tested using CMV spiked human saliva and urine samples. Sensitivity of the assay was â¼10 infectious units (IU)/mL. Specificity of the assay was robust and failed to detect other herpesviruses. Collectively, we have designed and validated a rapid diagnostic for CMV that overcomes limitations of the current standard diagnostic. This assay has the potential to be used as a point-of-care screening tool in transplant and neonatal settings.
Asunto(s)
Infecciones por Citomegalovirus , Citomegalovirus , Recién Nacido , Humanos , Citomegalovirus/genética , Sistemas CRISPR-Cas , Prueba de Diagnóstico Rápido , Reacción en Cadena en Tiempo Real de la Polimerasa , ADN Viral/análisisRESUMEN
Background: An estimated 55.5% and 37.3% of people globally with type 2 diabetes (T2D) will have concomitant non-alcoholic fatty liver disease (NAFLD) and the more severe fibroinflammatory stage, non-alcoholic steatohepatitis (NASH). NAFLD and NASH prevalence is projected to increase exponentially over the next 20 years. Bayesian Networks (BNs) offer a powerful tool for modelling uncertainty and visualising complex systems to provide important mechanistic insight. Methods: We applied BN modelling and probabilistic reasoning to explore the probability of NASH in two extensively phenotyped clinical cohorts: 1) 211 participants with T2D pooled from the MODIFY study & UK Biobank (UKBB) online resource; and 2) 135 participants without T2D from the UKBB. MRI-derived measures of visceral (VAT), subcutaneous (SAT), skeletal muscle (SMI), liver fat (MRI-PDFF), liver fibroinflammatory change (liver cT1) and pancreatic fat (MRI-PDFF) were combined with plasma biomarkers for network construction. NASH was defined according to liver PDFF >5.6% and liver cT1 >800ms. Conditional probability queries were performed to estimate the probability of NASH after fixing the value of specific network variables. Results: In the T2D cohort we observed a stepwise increase in the probability of NASH with each obesity classification (normal weight: 13%, overweight: 23%, obese: 36%, severe obesity: 62%). In the T2D and non-T2D cohorts, elevated (vs. normal) VAT conferred a 20% and 1% increase in the probability of NASH, respectively, while elevated SAT caused a 7% increase in NASH risk within the T2D cohort only. In those with T2D, reducing HbA1c from the 'high' to 'low' value reduced the probability of NASH by 22%. Conclusion: Using BNs and probabilistic reasoning to study the probability of NASH, we highlighted the relative contribution of obesity, ectopic fat (VAT and liver) and glycaemic status to increased NASH risk, namely in people with T2D. Such modelling can provide insights into the efficacy and magnitude of public health and pharmacological interventions to reduce the societal burden of NASH.
Asunto(s)
Diabetes Mellitus Tipo 2 , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/etiología , Diabetes Mellitus Tipo 2/complicaciones , Teorema de Bayes , Control Glucémico , Obesidad/complicacionesRESUMEN
Varenicline (Chantix) is an FDA-approved smoking cessation aid that is pharmacologically similar to nicotine, the primary addictive component found within tobacco. In support of this similarity, previous drug discrimination research in rats has reported that the internal or interoceptive stimulus effects of nicotine and varenicline share stimulus elements. Those shared elements appear to be mediated, in part, by overlapping action at alpha4beta2-containing nicotinic acetylcholine receptors (nAChRs). The research supporting this conclusion, however, has only used nicotine, and not varenicline, as the training drug. Accordingly, we used the discriminated goal tracking (DGT) task in which 1 mg/kg varenicline signaled intermittent access to sucrose. On separate intermixed saline days, sucrose was not available. Rats acquired the discrimination as measured by a differential increase in dipper entries (goal tracking) evoked by varenicline. These rats then received a series of tests with several doses of varenicline, nicotine, nornicotine (a metabolite of nicotine and tobacco alkaloid), sazetidine-A (a partial alpha4beta2 agonist), PHA-543613 (an alpha7 agonist), and bupropion (a norepinephrine and dopamine reuptake inhibitor). Control of goal tracking by varenicline was dose-dependent. Nicotine and nornicotine evoked responding comparable to the varenicline training dose indicating full substitution. Sazetidine-A partially substituted for the varenicline stimulus, whereas bupropion and PHA-543613 evoked little to no varenicline-like responding. These findings indicate that varenicline can serve as the training stimulus in the DGT task. Further, stimulus control of varenicline in the DGT task is driven by its partial agonist activity at alpha4beta2-containing nAChRs. The use of this approach could lead to a better understanding of the pharmacological action of varenicline and help guide treatment geared towards tobacco cessation through a more targeted development of novel synthetically designed, subunit-specific pharmacological interventions.
Asunto(s)
Motivación , Receptores Nicotínicos , Agentes para el Cese del Hábito de Fumar , Vareniclina , Animales , Ratas , Benzazepinas/farmacología , Bupropión , Objetivos , Nicotina/farmacología , Agonistas Nicotínicos/farmacología , Quinoxalinas/farmacología , Receptores Nicotínicos/metabolismo , Vareniclina/farmacología , Agentes para el Cese del Hábito de Fumar/farmacología , Motivación/efectos de los fármacosRESUMEN
INTRODUCTION: Occupational exposure to repetitive, low-level blasts in military training and combat has been tied to subconcussive injury and poor health outcomes for service members. Most low-level blast studies to date have focused on explosive breaching and firing heavy weapon systems; however, there is limited research on the repetitive blast exposure and physiological effects that mortarmen experience when firing mortar weapon systems. Motivated by anecdotal symptoms of mortarmen, the purpose of this paper is to characterize this exposure and its resulting neurocognitive effects in order to provide preliminary findings and actionable recommendations to safeguard the health of mortarmen. MATERIALS AND METHODS: In collaboration with the U.S. Army Rangers at Fort Benning, blast exposure, symptoms, and pupillary light reflex were measured during 3 days of firing 81 mm and 120 mm mortars in training. Blast exposure analysis included the examination of the blast overpressure (BOP) and cumulative exposure by mortarman position, as well as comparison to the 4 psi safety threshold. Pupillary light reflex responses were analyzed with linear mixed effects modeling. All neurocognitive results were compared between mortarmen (n = 11) and controls (n = 4) and cross-compared with blast exposure and blast history. RESULTS: Nearly 500 rounds were fired during the study, resulting in a high cumulative blast exposure for all mortarmen. While two mortarmen had average BOPs exceeding the 4 psi safety limit (Fig. 2), there was a high prevalence of mTBI-like symptoms among all mortarmen, with over 70% experiencing headaches, ringing in the ears, forgetfulness/poor memory, and taking longer to think during the training week (n ≥ 8/11). Mortarmen also had smaller and slower pupillary light reflex responses relative to controls, with significantly slower dilation velocity (P < 0.05) and constriction velocity (P < 0.10). CONCLUSION: Mortarmen experienced high cumulative blast exposure coinciding with altered neurocognition that is suggestive of blast-related subconcussive injury. These neurocognitive effects occurred even in mortarmen with average BOP below the 4 psi safety threshold. While this study was limited by a small sample size, its results demonstrate a concerning health risk for mortarmen that requires additional study and immediate action. Behavioral changes like ducking and standing farther from the mortar when firing can generally help reduce mortarmen BOP exposure, but we recommend the establishment of daily cumulative safety thresholds and daily firing limits in training to reduce cumulative blast exposure, and ultimately, improve mortarmen's quality of life and longevity in service.
Asunto(s)
Traumatismos por Explosión , Personal Militar , Humanos , Personal Militar/psicología , Calidad de Vida , Explosiones , Traumatismos por Explosión/complicaciones , Traumatismos por Explosión/diagnósticoRESUMEN
BACKGROUND: Approximately 3,900 Americans die every month of opioid overdose. The total economic burden of the opioid epidemic is estimated to be more than $78 billion annually. We sought to determine whether postoperative opioid-prescribing practice variation exists in foot and ankle surgery. METHODS: We administered a voluntary, anonymous, online questionnaire consisting of six foot and ankle surgery scenarios followed by a demographics section. The purpose of the demographics section was to gather characteristics of podiatric foot and ankle surgeons. We invited podiatric foot and ankle surgeons practicing in the United States to complete the questionnaire via e-mail from the American Podiatric Medical Association's membership list. For each scenario, respondents selected the postoperative opioid(s) that they would prescribe at the time of surgery, as well as the dose, frequency, and number of "pills" (dosage units). We developed multiple linear regression models to identify associations between prescriber characteristics and two measures of opioid quantity: dosage units and morphine milligram equivalents. RESULTS: Eight hundred sixty podiatric foot and ankle surgeons completed the survey. The median number of dosage units never exceeded 30 regardless of the foot and ankle surgery. Years in practice correlated with reduction in dosage units at the time of surgery. Compared with the orthopedic community, podiatric foot and ankle surgeons prescribe approximately 25% less dosage units than orthopedic foot and ankle surgeons. CONCLUSIONS: Postoperative opioid-prescribing practice variation exists in foot and ankle surgery. Further research is warranted to determine whether additional education is needed for young surgeons.
Asunto(s)
Analgésicos Opioides , Ortopedia , Humanos , Estados Unidos , Tobillo/cirugía , Dolor Postoperatorio , Encuestas y Cuestionarios , Pautas de la Práctica en MedicinaRESUMEN
BACKGROUND: Tuberculosis remains a leading cause of global mortality, especially for adults and children living with HIV (CLHIV) underdiagnosed by sputum-based assays. Non-sputum-based assays are needed to improve tuberculosis diagnosis and tuberculosis treatment monitoring. Our aim in this study was to determine whether ultrasensitive detection of Mycobacterium tuberculosis cell-free DNA (Mtb-cfDNA) in blood can diagnose tuberculosis and evaluate tuberculosis treatment responses. METHODS: In this molecular diagnostics study we analysed archived serum from two patient populations evaluated for tuberculosis in Eswatini and Kenya to detect Mtb-cfDNA, analysing serum from all individuals who had both sufficient serum volumes and clear diagnostic results. An optimised CRISPR-mediated tuberculosis (CRISPR-TB) assay was used to detect Mtb-cfDNA in serum at enrolment from adults and children with presumptive tuberculosis and their asymptomatic household contacts, and at enrolment and during tuberculosis treatment from a cohort of symptomatic CLHIV at high risk for tuberculosis, who provided longitudinal serum at enrolment and during tuberculosis treatment. FINDINGS: CRISPR-TB identified microbiologically and clinically confirmed tuberculosis cases in the predominantly HIV-negative Eswatini adult cohort with 96% sensitivity (27 [96%] of 28, 95% CI 80-100) and 94% specificity (16 [94%] of 17, 71-100), and with 83% sensitivity (5 [83%] of 6, 36-100) and 95% specificity (21 [95%] of 22, 77-100) in the paediatric cohort, including all six cases of extrapulmonary tuberculosis. In the Kenyan CLHIV cohort, CRISPR-TB detected all (13 [100%] of 13, 75-100) confirmed tuberculosis cases and 85% (39 [85%] of 46, 71-94) of unconfirmed tuberculosis cases diagnosed by non-microbiological clinical findings. CLHIV who were CRISPR-TB positive at enrolment had a 2·4-times higher risk of mortality by 6 months after enrolment. Mtb-cfDNA signal decreased after tuberculosis treatment initiation, with near or complete Mtb-cfDNA clearance by 6 months after tuberculosis treatment initiation. INTERPRETATION: CRISPR-mediated detection of circulating Mtb-cfDNA shows promise to increase the identification of paediatric tuberculosis and HIV-associated tuberculosis, and potential for early diagnosis and rapid monitoring of tuberculosis treatment responses. FUNDING: US Department of Defense, National Institute of Child Health and Human Development, National Institute of Allergy and Infectious Diseases, University of Washington Center for AIDS Research, and the Weatherhead Presidential Endowment fund.