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1.
Am J Physiol Heart Circ Physiol ; 322(2): H246-H259, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34951541

RESUMO

Diabetes mellitus (DM) is a leading risk factor for age-related dementia, but the mechanisms involved are not well understood. We previously discovered that hyperglycemia induced impaired myogenic response (MR) and cerebral blood flow (CBF) autoregulation in 18-mo-old DM rats associated with blood-brain barrier (BBB) leakage, impaired neurovascular coupling, and cognitive impairment. In the present study, we examined whether reducing plasma glucose with a sodium-glucose cotransporter-2 inhibitor (SGLT2i) luseogliflozin can ameliorate cerebral vascular and cognitive function in diabetic rats. Plasma glucose and HbA1c levels of 18-mo-old DM rats were reduced, and blood pressure was not altered after treatment with luseogliflozin. SGLT2i treatment restored the impaired MR of middle cerebral arteries (MCAs) and parenchymal arterioles and surface and deep cortical CBF autoregulation in DM rats. Luseogliflozin treatment also rescued neurovascular uncoupling, reduced BBB leakage and cognitive deficits in DM rats. However, SGLT2i did not have direct constrictive effects on vascular smooth muscle cells and MCAs isolated from normal rats, although it decreased reactive oxygen species production in cerebral vessels of DM rats. These results provide evidence that normalization of hyperglycemia with an SGLT2i can reverse cerebrovascular dysfunction and cognitive impairments in rats with long-standing hyperglycemia, possibly by ameliorating oxidative stress-caused vascular damage.NEW & NOTEWORTHY This study demonstrates that luseogliflozin, a sodium-glucose cotransporter-2 inhibitor, improved CBF autoregulation in association with reduced vascular oxidative stress and AGEs production in the cerebrovasculature of 18-mo-old DM rats. SGLT2i also prevented BBB leakage, impaired functional hyperemia, neurodegeneration, and cognitive impairment seen in DM rats. Luseogliflozin did not have direct constrictive effects on VSMCs and MCAs isolated from normal rats. These results provide evidence that normalization of hyperglycemia with an SGLT2i can reverse cerebrovascular dysfunction and cognitive impairments in rats with long-standing hyperglycemia, possibly by ameliorating oxidative stress-caused vascular damage.


Assuntos
Demência Vascular/tratamento farmacológico , Angiopatias Diabéticas/tratamento farmacológico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Sorbitol/análogos & derivados , Animais , Arteríolas/efeitos dos fármacos , Arteríolas/fisiopatologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiopatologia , Células Cultivadas , Circulação Cerebrovascular , Cognição , Masculino , Artéria Cerebral Média/efeitos dos fármacos , Artéria Cerebral Média/fisiopatologia , Ratos , Ratos Sprague-Dawley , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Sorbitol/farmacologia , Sorbitol/uso terapêutico
2.
Am J Physiol Regul Integr Comp Physiol ; 322(4): R299-R308, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35107024

RESUMO

Prepubertal obesity (PPO) has emerged as a major health problem over the past few decades and is a risk factor for the development of proteinuria. The current study investigated whether the development of renal injury in the obese SSLepR mutant strain occurs before puberty. When determining the temporal changes in serum sex hormones in female and male SS and SSLepR mutant rats between 4 and 10 wk of age, we only observed significant increases in estradiol and testosterone levels in female and male SS rats at 10 wk of age than at 4 wk of age. The results suggest that studying both strains between 4 and 8 wk of age is appropriate to study the effects of PPO on renal injury in this model. Proteinuria was significantly higher in SSLepR mutant rats as opposed to the values observed in SS rats at 8 wk of age, and we did not observe any sex differences in proteinuria in either strain. The kidneys from the SSLepR mutant rats displayed significant glomerular and tubular injury and renal fibrosis versus the values measured in SS rats without any sex differences. Overall, we observed increased immune cell infiltration in the kidneys from SSLepR mutant rats compared with SS rats. Interestingly, female SSLepR mutant rats displayed significant increases in not only M1 macrophages (proinflammatory) but also M2 macrophages (anti-inflammatory) versus male SSLepR mutant rats. These results suggest the SSLepR mutant rat may be a useful model to study early progression of obesity-related renal injury before the onset of puberty.


Assuntos
Nefropatias , Rim , Animais , Feminino , Humanos , Nefropatias/genética , Masculino , Obesidade/complicações , Obesidade/genética , Proteinúria/genética , Puberdade , Ratos
3.
Anal Chem ; 93(27): 9337-9344, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-33989499

RESUMO

Yersinia pestis is a Gram-negative bacterium that is the causative agent of plague and is widely recognized as a potential biological weapon. Due to the high fatality rate of plague when diagnosis is delayed, the development of rapid, sensitive, specific, and cost-effective methods is needed for its diagnosis. The Y. pestis low calcium response V (LcrV) protein has been identified as a potential microbial biomarker for the diagnosis of plague. In this paper, we present a highly sensitive, paper-based, vertical flow immunoassay (VFI) prototype for the detection of LcrV and the diagnosis of plague. An antigen-capture assay using monoclonal antibodies is employed to capture and detect the LcrV protein, using a colorimetric approach. In addition, the effect of miniaturizing the VFI device is explored based on two different sizes of VFI platforms, denoted as "large VFI" and "mini VFI." Also, a comparative analysis is performed between the VFI platform and a lateral flow immunoassay (LFI) platform to exhibit the improved assay sensitivity suitable for point-of-care (POC) diagnostics. The analytical sensitivity or limit of detection (LOD) in the mini VFI is approximately 0.025 ng/mL, that is, 10 times better than that of the large VFI platform or 80 times over a standard lateral flow configuration. The low LOD of the LcrV VFI appears to be highly suitable for testing clinical samples and potentially diagnosing plague at earlier time points. In addition, optimization of the gold nanoparticle (AuNP) concentration, nanomaterial plasmonic properties, and flow velocity analysis could improve the performance of the VFI. Furthermore, we developed automated image analysis software that shows potential for integrating the diagnostic system into a smartphone. These methods and findings demonstrate that the VFI platform is a highly sensitive device for detecting the LcrV and potentially many other biomarkers.


Assuntos
Nanopartículas Metálicas , Peste , Yersinia pestis , Anticorpos Antibacterianos , Antígenos de Bactérias , Ouro , Humanos , Imunoensaio , Peste/diagnóstico
4.
J Pharmacol Exp Ther ; 376(2): 240-249, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33277348

RESUMO

Lysophosphatidic acid (LPA) is a bioactive lipid mediator that has been implicated in the pathophysiology of kidney disease. However, few studies have attempted to measure changes in the levels of various LPA species in the kidney after the development of renal disease. The present study measured the renal LPA levels during the development of kidney disease in rat models of hypertension, diabetes, and obstructive nephropathy using liquid chromatography/mass spectrometry/mass spectrometry. LPA levels (sum of 16:0, 18:0, 18:1, 18:2, and 20:4 LPA) were higher in the renal cortex of hypertensive Dahl salt-sensitive (Dahl S) rats fed a high-salt diet than those in normotensive rats fed a low-salt diet (296.6 ± 22.9 vs. 196.3 ± 8.5 nmol/g protein). LPA levels were elevated in the outer medulla of the kidney of streptozotocin-induced type 1 diabetic Dahl S rats compared with control rats (624.6 ± 129.5 vs. 318.8 ± 17.1 nmol/g protein). LPA levels were also higher in the renal cortex of 18-month-old, type 2 diabetic nephropathy (T2DN) rats with more severe renal injury than in 6-month-old T2DN rats (184.9 ± 20.9 vs. 116.9 ± 6.0 nmol/g protein). LPA levels also paralleled the progression of renal fibrosis in the renal cortex of Sprague-Dawley rats after unilateral ureteral obstruction (UUO). Administration of an LPA receptor antagonist, Ki16425, reduced the degree of renal fibrosis in UUO rats. These results suggest that the production of renal LPA increases during the development of renal injury and contributes to renal fibrosis. SIGNIFICANCE STATEMENT: The present study reveals that the lysophosphatidic acid (LPA) levels increase in the kidney in rat models of hypertension, diabetes, and obstructive nephropathy, and administration of an LPA receptor antagonist attenuates renal fibrosis. Therapeutic approaches that target the formation or actions of renal LPA might be renoprotective and have therapeutic potential.


Assuntos
Nefropatias Diabéticas/metabolismo , Hipertensão Renal/metabolismo , Lisofosfolipídeos/metabolismo , Animais , Nefropatias Diabéticas/patologia , Fibrose , Hipertensão Renal/patologia , Isoxazóis/farmacologia , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Lisofosfolipídeos/antagonistas & inibidores , Masculino , Propionatos/farmacologia , Ratos , Ratos Endogâmicos Dahl , Ratos Sprague-Dawley
5.
Telemed J E Health ; 27(12): 1393-1398, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33691080

RESUMO

Background: For newborns requiring transfer to a higher level of care, stabilization before the arrival of the transport team is essential. Telemedicine consultations with a neonatologist may improve local providers' ability to stabilize a newborn during this critical interval. The purpose of this study was to describe the use of telemedicine for stabilizing newborns who were transferred from one of six rural hospitals to a regional neonatal intensive care unit in northern California and to examine the association between telemedicine use and time needed to stabilize the newborn. Materials and Methods: We collected data on all newborns who were transferred after either a telemedicine or telephone consultation with a neonatologist between April 2014 and June 2018. We used multiple regression to examine the association between the use of telemedicine and stabilization time, adjusting for gestational age, 5-min Apgar score, birth weight, site, and primary reason for consultation. Results: In total, 162 infants (77.5%) received a telephone consultation and 47 (22.5%) received a telemedicine consultation. Neonates who received telemedicine had a significantly greater severity of illness, as measured by mean 5-min Apgar score (6.9 vs. 7.8, p = 0.008) and Transport Risk Index of Physiologic Stability version II (TRIPS-II) score (14.4 vs. 6.0, p < 0.001). There was no significant difference in stabilization time for telemedicine consultations compared with telephone consultations in the adjusted analysis (adjusted mean difference: -1.80, 95% confidence interval: -16.0 to 12.4, p = 0.802). Conclusions: Although we found no difference in stabilization times between modes of consultation, telemedicine may be helpful for stabilizing infants with a higher severity of illness, particularly those in respiratory distress. Future studies should examine the impact of telemedicine on specific interventions.


Assuntos
Hospitais Rurais , Telemedicina , Pré-Escolar , Hospitais Comunitários , Humanos , Recém-Nascido , Encaminhamento e Consulta , Telefone
6.
Curr Osteoporos Rep ; 16(3): 312-319, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29667012

RESUMO

PURPOSE OF REVIEW: This review explores how the relationships between bone marrow adipose tissue (BMAT) adipogenesis with advancing age, obesity, and/or bone diseases (osteopenia or osteoporosis) contribute to mechanisms underlying musculoskeletal pathophysiology. RECENT FINDINGS: Recent studies have re-defined adipose tissue as a dynamic, vital organ with functions extending beyond its historic identity restricted solely to that of an energy reservoir or sink. "State of the art" methodologies provide novel insights into the developmental origin, physiology, and function of different adipose tissue depots. These include genetic tracking of adipose progenitors, viral vectors application, and sophisticated non-invasive imaging modalities. While constricted within the rigid bone cavity, BMAT vigorously contributes to local and systemic metabolic processes including hematopoiesis, osteogenesis, and energy metabolism and undergoes dynamic changes as a function of age, diet, bone topography, or sex. These insights will impact future research and therapies relating to osteoporosis.


Assuntos
Adipócitos/metabolismo , Adipogenia , Tecido Adiposo/metabolismo , Envelhecimento/metabolismo , Células da Medula Óssea/metabolismo , Adipócitos/citologia , Adipócitos/fisiologia , Tecido Adiposo Marrom/citologia , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Marrom/fisiologia , Tecido Adiposo Branco/citologia , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/fisiologia , Doenças Ósseas Metabólicas/metabolismo , Medula Óssea/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Osso e Ossos/metabolismo , Metabolismo Energético , Hematopoese , Humanos , Obesidade/metabolismo , Osteogênese , Osteoporose/metabolismo
7.
Breast J ; 23(6): 677-686, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28097781

RESUMO

The Oncotype DX breast cancer assay (Genomic Health, Redwood City, CA) is increasingly being used to guide treatment decisions for patients with early stage, hormone-positive, Her-2-negative breast cancer. The utility of the Oncotype DX in decision making for treatment of invasive lobular carcinoma (ILC) has not been investigated as the results reported by Genomic Health are largely in a population with invasive ductal carcinoma (IDC). The authors hypothesized that the Oncotype DX recurrence score (RS) distribution for ILC is different than that for IDC. We performed a retrospective analysis of early stage breast cancer patients treated at Penn State Cancer Institute from 2001 to 2011 and identified 102 patients with ILC. We also pulled RS data from our institution's prospective registry of consecutive patients with early stage IDC treated during the same time period. Median follow-up was 55 months. We found that the RS distribution for ILC differed significantly from that of IDC (p = 0.024). We also found a statistically significant difference in the RS distribution between the pure ILC and pleomorphic ILC subtypes (p = 0.027). The Oncotype DX RS distribution in ILC is unique, differing significantly from that in ductal carcinoma. Consequently, the clinical usefulness and cost-effectiveness of the Oncotype DX in guiding treatment for ILC should be further investigated.


Assuntos
Neoplasias da Mama/mortalidade , Carcinoma Ductal de Mama/mortalidade , Carcinoma Lobular/mortalidade , Perfilação da Expressão Gênica/métodos , Recidiva Local de Neoplasia/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/genética , Carcinoma Lobular/patologia , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Perfilação da Expressão Gênica/economia , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Pennsylvania , Sistema de Registros , Estudos Retrospectivos , Sensibilidade e Especificidade
8.
RNA Biol ; 13(10): 955-972, 2016 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-27419845

RESUMO

Many cellular functions, such as translation, require ribonucleoproteins (RNPs). The biogenesis of RNPs is a multi-step process that, depending on the RNP, can take place in many cellular compartments. Here we examine 2 different RNPs: telomerase and small Cajal body-specific RNPs (scaRNPs). Both of these RNPs are enriched in the Cajal body (CB), which is a subnuclear domain that also has high concentrations of another RNP, small nuclear RNPs (snRNPs). SnRNPs are essential components of the spliceosome, and scaRNPs modify the snRNA component of the snRNP. The CB contains many proteins, including WRAP53, SMN and coilin, the CB marker protein. We show here that coilin, SMN and coilp1, a newly identified protein encoded by a pseudogene in human, associate with telomerase RNA and a subset of scaRNAs. We also have identified a processing element within box C/D scaRNA. Our findings thus further strengthen the connection between the CB proteins coilin and SMN in the biogenesis of telomeras e and box C/D scaRNPs, and reveal a new player, coilp1, that likely participates in this process.


Assuntos
Corpos Enovelados/genética , Proteínas Nucleares/metabolismo , Ribonucleoproteínas Nucleares Pequenas/genética , Proteína 1 de Sobrevivência do Neurônio Motor/metabolismo , Telomerase/genética , Animais , Corpos Enovelados/metabolismo , Células HeLa , Humanos , Camundongos , Proteínas Nucleares/genética , Ligação Proteica , Pseudogenes , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Telomerase/metabolismo
9.
New Phytol ; 201(2): 498-504, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24117700

RESUMO

Understanding the effects of elevated [CO2 ] on plant community structure is crucial to predicting ecosystem responses to global change. Early predictions suggested that productivity in deserts would increase via enhanced water-use efficiency under elevated [CO2], but the response of intact arid plant communities to elevated [CO2 ] is largely unknown. We measured changes in perennial plant community characteristics (cover, species richness and diversity) after 10 yr of elevated [CO2] exposure in an intact Mojave Desert community at the Nevada Desert Free-Air CO2 Enrichment (FACE) Facility. Contrary to expectations, total cover, species richness, and diversity were not affected by elevated [CO2]. Over the course of the experiment, elevated [CO2] had no effect on changes in cover of the evergreen C3 shrub, Larrea tridentata; alleviated decreases in cover of the C4 bunchgrass, Pleuraphis rigida; and slightly reduced the cover of C3 drought-deciduous shrubs. Thus, we generally found no effect of elevated [CO2] on plant communities in this arid ecosystem. Extended drought, slow plant growth rates, and highly episodic germination and recruitment of new individuals explain the lack of strong perennial plant community shifts after a decade of elevated [CO2].


Assuntos
Biodiversidade , Dióxido de Carbono/metabolismo , Mudança Climática , Fenômenos Fisiológicos Vegetais , Clima Desértico , Secas , Germinação , Larrea/crescimento & desenvolvimento , Larrea/metabolismo , Larrea/fisiologia , Nevada , Poaceae/crescimento & desenvolvimento , Poaceae/metabolismo , Poaceae/fisiologia , Dinâmica Populacional , Especificidade da Espécie , Água/metabolismo
10.
Glob Chang Biol ; 20(3): 879-92, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24115504

RESUMO

Desert annuals are a critically important component of desert communities and may be particularly responsive to increasing atmospheric (CO2 ) because of their high potential growth rates and flexible phenology. During the 10-year life of the Nevada Desert FACE (free-air CO2 enrichment) Facility, we evaluated the productivity, reproductive allocation, and community structure of annuals in response to long-term elevated (CO2 ) exposure. The dominant forb and grass species exhibited accelerated phenology, increased size, and higher reproduction at elevated (CO2 ) in a wet El Niño year near the beginning of the experiment. However, a multiyear dry cycle resulted in no increases in productivity or reproductive allocation for the remainder of the experiment. At the community level, early indications of increased dominance of the invasive Bromus rubens at elevated (CO2 ) gave way to an absence of Bromus in the community during a drought cycle, with a resurgence late in the experiment in response to higher rainfall and a corresponding high density of Bromus in a final soil seed bank analysis, particularly at elevated (CO2 ). This long-term experiment resulted in two primary conclusions: (i) elevated (CO2 ) does not increase productivity of annuals in most years; and (ii) relative stimulation of invasive grasses will likely depend on future precipitation, with a wetter climate favoring invasive grasses but currently predicted greater aridity favoring native dicots.


Assuntos
Dióxido de Carbono , Fenômenos Fisiológicos Vegetais , Biomassa , Bromus/fisiologia , Clima Desértico , Ecossistema , Espécies Introduzidas , Lepidium/fisiologia , Nevada , Reprodução , Estações do Ano
11.
Biomed Microdevices ; 16(6): 905-14, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25106501

RESUMO

We report a microfluidic device and measurement method to perform real-time PCR (or qPCR) in a miniaturized configuration for on-chip implementation using reaction volumes of less than 20 µL. The qPCR bioreactor is designed as a module to be embedded in an automated sample-in/profile-out system for rapid DNA biometrics or human identification. The PCR mixture is excited with a 505 nm diode-pumped solid-state laser (DPSSL) and the fluorescence build-up is measured using optical fibers directly embedded to the sidewalls of the microfluidic qPCR bioreactor. We discuss manufacturing and operating parameters necessary to adjust the internal surface conditions and temperature profiles of the bioreactor and to optimize the yield and quality of the PCR reaction for the amplification of 62 bp hTERT intron fragments using the commercial Quantifiler® kit (Life Technologies, Carlsbad, CA) commonly accepted for genotyping analysis. We designed a microfluidic device suitable for continuously processing a specimen by efficiently mixing the reagents from the kit to a set volume of DNA template on chip. Our approach relies on a calibration curve for the specific device using control DNA. We successfully applied this method to determine the concentration of genomic DNA extracted from a buccal swab on separate microfluidic devices which are operated upstream the qPCR device and perform buccal swab lysis and buccal DNA extraction. A precise correlation between the amount determined on chip and that obtained using a commercial cycler is demonstrated.


Assuntos
Técnicas de Genotipagem , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas , Reação em Cadeia da Polimerase em Tempo Real , DNA/química , DNA/genética , DNA/isolamento & purificação , Feminino , Técnicas de Genotipagem/instrumentação , Técnicas de Genotipagem/métodos , Humanos , Lasers Semicondutores , Masculino , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Mucosa Bucal , Reação em Cadeia da Polimerase em Tempo Real/instrumentação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Telomerase/genética
12.
Prostaglandins Other Lipid Mediat ; 113-115: 45-51, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25151892

RESUMO

Previous studies have indicated that cytochrome P450 (CYP) metabolites of arachidonic acid (AA), i.e., 20-hydroxyeicosatetraenoic acid (20-HETE) and epoxyeicosatrienoic acids (EETs), play an important role in the regulation of renal tubular and vascular function. The present study for the first time profiled HETEs and epoxygenase derived dihydroxyeicosatetraenoic acid diHETEs levels in spot urines and plasma in 262 African American patients from the University of Mississippi Chronic Kidney Disease Clinic and 31 African American controls. Significant correlations in eGFR and urinary 20-HETE/creatinine and 19-HETE/creatinine levels were observed. The eGFR increased by 17.47 [p=0.001] and 60.68 [(p=0.005]ml/min/for each ng/mg increase in 20-HETE and 19-HETE levels, respectively. Similar significant positive associations were found between the other urinary eicosanoids and eGFR and also with 19-HETE/urine creatinine concentration and proteinuria. We found that approximately 80% of plasma HETEs and 30% diHETEs were glucuronidated and the fractional excretion of 20-HETE was less than 1%. These results suggest that there is a significant hepatic source of urinary 20-HETE glucuronide and EETs with extensive renal biotransformation to metabolites which may play a role in the pathogenesis of CKD.


Assuntos
Negro ou Afro-Americano , Sistema Enzimático do Citocromo P-450/urina , Eicosanoides/urina , Taxa de Filtração Glomerular/fisiologia , Insuficiência Renal Crônica/etnologia , Insuficiência Renal Crônica/urina , Adulto , Creatinina/sangue , Creatinina/urina , Eicosanoides/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteinúria/urina , Análise de Regressão , Insuficiência Renal Crônica/fisiopatologia , Estados Unidos
13.
J Appl Toxicol ; 33(7): 644-51, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22271348

RESUMO

Cytochrome P450 (CYP)-mediated desulfuration of methyl parathion results in mechanism-based inhibition of the enzyme. Although previous data suggest that reactive sulfur is released and binds to the apoprotein, the identities of neither the adduct(s) nor the affected amino acid(s) have been clearly determined. In this study, nanospray tandem mass spectroscopy was used to analyze peptide digests of CYP resolved by SDS-PAGE from liver microsomes of male rats following incubation in the absence or presence of methyl parathion. Oxidative desulfuration was confirmed by measurement of methyl paraoxon, and inhibition of specific CYP isozymes was determined by measurement of testosterone hydroxylation. Total CYP content was quantified spectrophotometrically. Incubation of microsomes with methyl parathion decreased CYP content by 58%. This effect was not associated with a comparable increase in absorbance at 420 nm, suggesting the displacement of heme from the apoprotein. Rates of testosterone 2ß- and 6ß-hydroxylation, respectively, were reduced to 8 and 2%, implicating CYP3A and CYP2C11 in the oxidative desulfuration of methyl parathion. Mass spectrometric analysis identified 96 amu adducts to cysteines 64 and 378 of CYP3A1. In addition, a peptide containing cysteine 433 that coordinates with heme was possibly modified as it was detected in control, but not methyl parathion samples. A comparison of rat CYP3A1 with human CYP3A4 suggests that cysteines 64 and 378 reside along the substrate channel, remote from the active site. Alteration of these residues might modulate substrate entry to the binding pocket of the enzyme.


Assuntos
Sistema Enzimático do Citocromo P-450/análise , Inseticidas/metabolismo , Metil Paration/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Humanos , Hidroxilação , Inseticidas/toxicidade , Isoenzimas/metabolismo , Cinética , Masculino , Espectrometria de Massas , Metil Paration/toxicidade , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Modelos Moleculares , Oxirredução , Proteômica , Ratos , Ratos Sprague-Dawley , Espectrofotometria Ultravioleta , Enxofre/metabolismo , Testosterona/metabolismo
14.
Mil Med ; 188(3-4): e824-e828, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-34453171

RESUMO

INTRODUCTION: We aimed to evaluate the effect of the SARS-COV2 pandemic on chaplain utilization at Brooke Army Medical Center. Our hypothesis was that multiple pandemic-related factors led to a care environment with increased mental and spiritual stress for patients and their families, leading to an increased need for adjunct services such as chaplaincy. MATERIALS AND METHODS: This was a single-institution retrospective chart review study that evaluated the records of 10,698 patients admitted between July 1, 2019, and January 31, 2020, or between July 1, 2020, and January 31, 2021. Our primary study outcomes included the number of chaplain consultations, the number of visits per consultation, and the time of visits between the two study cohorts. Secondary outcomes included inpatient mortality and the number of end-of-life visits. We also isolated a subgroup of patients admitted with COVID-19 and compared their outcomes with the two larger cohorts. Statistical analysis included t-test or chi-squared test, based on the variable. This study was reviewed and approved by the Brooke Army Medical Center Institutional Review Board (IRB ID C.2021.010e). RESULTS: Fewer consults were performed during the study period affected by the SARS-COV2 pandemic (4814 vs. 5884, P-value <.01). There were fewer individual visits per consult during the study period affected by the SARS-COV2 pandemic (1.44 vs. 1.64, P-value <.01), which led to fewer overall time spent per consult (37.41 vs. 41.19 minutes, P-value <.01). The 2020 cohort (without COVID-19 cases) demonstrated a higher mortality rate than the 2019 cohort (2.8% vs. 1.9%, P-value <.01). The COVID-19 diagnosis cohort demonstrated a much higher mortality rate compared to other patients in the 2020 cohort (19.3% vs. 2.8%, P-value <.01). We demonstrated the relative need for EOL consults by presenting the ratio of EOL consults to inpatient deaths. This ratio was highest for the COVID-19 diagnosis cohort (0.76) compared to the 2020 cohort (0.50) and the 2019 cohort (0.60). CONCLUSIONS: This study demonstrates that factors related to the SARS-COV2 pandemic resulted in fewer chaplaincy consults in our inpatient setting. We did not find other reports of a change in the rate of chaplaincy consultation, but available reports suggest that many centers have had difficulty balancing the spiritual needs of patients with local exposure guidelines. Although fewer individual chaplain consults occurred during the SARS-COV2 pandemic, our chaplain service innovated by utilizing various phone, video, and web-based platforms to deliver spiritual support to our community. Our study also suggests that the patients most greatly affected by the pandemic have an increased need for spiritual support, especially at the end of life. Future studies in this subject should examine the effect of various types of chaplain services as they relate to the health and well-being of hospitalized patients.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , RNA Viral , SARS-CoV-2 , Estudos Retrospectivos , Pandemias , Teste para COVID-19
15.
Biosens Bioelectron ; 219: 114796, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36257115

RESUMO

This paper presents simple, fast, and sensitive detection of multiple biothreat agents by paper-based vertical flow colorimetric sandwich immunoassay for detection of Yersinia pestis (LcrV and F1) and Francisella tularensis (lipopolysaccharide; LPS) antigens using a vertical flow immunoassay (VFI) prototype with portable syringe pump and a new membrane holder. The capture antibody (cAb) printing onto nitrocellulose membrane and gold-labelled detection antibody (dAb) were optimized to enhance the assay sensitivity and specificity. Even though the paper pore size was relaxed from previous 0.1 µm to the current 0.45 µm for serum samples, detection limits as low as 0.050 ng/mL for LcrV and F1, and 0.100 ng/mL for FtLPS have been achieved in buffer and similarly in diluted serum (with LcrV and F1 LODs remained the same and LPS LOD reduced to 0.250 ng/mL). These were 40, 80, and 50X (20X for LPS in serum) better than those from lateral flow configuration. Furthermore, the comparison of multiplex format demonstrated low cross-reactivity and equal sensitivity to that of the singleplex assay. The optimized VFI platform thus provides a portable and rapid on-site monitoring system for multiplex biothreat detection with the potential for high sensitivity, specificity, reproducibility, and multiplexing capability, supporting its utility in remote and resource-limited settings.

16.
New Phytol ; 194(2): 464-476, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22348404

RESUMO

Night-time stomatal conductance (g(night)) occurs in many ecosystems, but the g(night) response to environmental drivers is relatively unknown, especially in deserts. Here, we conducted a Bayesian analysis of stomatal conductance (g) (N=5013) from 16 species in the Sonoran, Chihuahuan, Mojave and Great Basin Deserts (North America). We partitioned daytime g (g(day)) and g(night) responses by describing g as a mixture of two extreme (dark vs high light) behaviors. Significant g(night) was observed across 15 species, and the g(night) and g(day) behavior differed according to species, functional type and desert. The transition between extreme behaviors was determined by light environment, with the transition behavior differing between functional types and deserts. Sonoran and Chihuahuan C(4) grasses were more sensitive to vapor pressure difference (D) at night and soil water potential (Ψ(soil)) during the day, Great Basin C(3) shrubs were highly sensitive to D and Ψ(soil) during the day, and Mojave C(3) shrubs were equally sensitive to D and Ψ(soil) during the day and night. Species were split between the exhibition of isohydric or anisohydric behavior during the day. Three species switched from anisohydric to isohydric behavior at night. Such behavior, combined with differential D, Ψ(soil) and light responses, suggests that different mechanisms underlie g(day) and g(night) regulation.


Assuntos
Escuridão , Clima Desértico , Fenômenos Fisiológicos Vegetais , Estômatos de Plantas/fisiologia , Modelos Biológicos , América do Norte , Transpiração Vegetal/fisiologia , Especificidade da Espécie
17.
Nanoscale ; 14(10): 3658-3697, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35080544

RESUMO

Magnetic particle imaging (MPI) is an emerging tracer-based modality that enables real-time three-dimensional imaging of the non-linear magnetisation produced by superparamagnetic iron oxide nanoparticles (SPIONs), in the presence of an external oscillating magnetic field. As a technique, it produces highly sensitive radiation-free tomographic images with absolute quantitation. Coupled with a high contrast, as well as zero signal attenuation at-depth, there are essentially no limitations to where that can be imaged within the body. These characteristics enable various biomedical applications of clinical interest. In the opening sections of this review, the principles of image generation are introduced, along with a detailed comparison of the fundamental properties of this technique with other common imaging modalities. The main feature is a presentation on the up-to-date literature for the development of SPIONs tailored for improved imaging performance, and developments in the current and promising biomedical applications of this emerging technique, with a specific focus on theranostics, cell tracking and perfusion imaging. Finally, we will discuss recent progress in the clinical translation of MPI. As signal detection in MPI is almost entirely dependent on the properties of the SPION employed, this work emphasises the importance of tailoring the synthetic process to produce SPIONs demonstrating specific properties and how this impacts imaging in particular applications and MPI's overall performance.


Assuntos
Nanopartículas de Magnetita , Rastreamento de Células/métodos , Campos Magnéticos , Magnetismo/métodos , Tomografia/métodos
18.
Oecologia ; 167(2): 339-54, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21516309

RESUMO

During the first few years of elevated atmospheric [CO(2)] treatment at the Nevada Desert FACE Facility, photosynthetic downregulation was observed in desert shrubs grown under elevated [CO(2)], especially under relatively wet environmental conditions. Nonetheless, those plants maintained increased A (sat) (photosynthetic performance at saturating light and treatment [CO(2)]) under wet conditions, but to a much lesser extent under dry conditions. To determine if plants continued to downregulate during long-term exposure to elevated [CO(2)], responses of photosynthesis to elevated [CO(2)] were examined in two dominant Mojave Desert shrubs, the evergreen Larrea tridentata and the drought-deciduous Ambrosia dumosa, during the eighth full growing season of elevated [CO(2)] treatment at the NDFF. A comprehensive suite of physiological processes were collected. Furthermore, we used C labeling of air to assess carbon allocation and partitioning as measures of C sink activity. Results show that elevated [CO(2)] enhanced photosynthetic performance and plant water status in Larrea, especially during periods of environmental stress, but not in Ambrosia. δ(13)C analyses indicate that Larrea under elevated [CO(2)] allocated a greater proportion of newly assimilated C to C sinks than Ambrosia. Maintenance by Larrea of C sinks during the dry season partially explained the reduced [CO(2)] effect on leaf carbohydrate content during summer, which in turn lessened carbohydrate build-up and feedback inhibition of photosynthesis. δ(13)C results also showed that in a year when plant growth reached the highest rates in 5 years, 4% (Larrea) and 7% (Ambrosia) of C in newly emerging organs were remobilized from C that was assimilated and stored for at least 2 years prior to the current study. Thus, after 8 years of continuous exposure to elevated [CO(2)], both desert perennials maintained their photosynthetic capacities under elevated [CO(2)]. We conclude that C storage, remobilization, and partitioning influence the responsiveness of these desert shrubs during long-term exposure to elevated [CO(2)].


Assuntos
Ambrosia/fisiologia , Dióxido de Carbono/metabolismo , Carbono/metabolismo , Larrea/fisiologia , Fotossíntese , Análise de Variância , Carbono/análise , Dióxido de Carbono/análise , Meio Ambiente , Análise Multivariada , Nevada , Folhas de Planta/fisiologia , Estações do Ano
19.
Infect Dis Rep ; 13(4): 1061-1077, 2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34940407

RESUMO

Since the outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in December 2019, the spread of SARS-CoV2 infection has been escalating rapidly around the world. In order to provide more timely access to medical intervention, including diagnostic tests and medical treatment, the FDA authorized multiple test protocols for diagnostic tests from nasopharyngeal swab, saliva, urine, bronchoalveolar lavage and fecal samples. The traditional diagnostic tests for this novel coronavirus 2019 require standard processes of viral RNA isolation, reverse transcription of RNA to cDNA, then real-time quantitative PCR with the RNA templates extracted from the patient samples. Recently, many reports have demonstrated a direct detection of SARS-Co-V2 genomic material from saliva samples without any RNA isolation step. To make the rapid detection of SARS-Co-V2 infection more accessible, a point-of-care type device was developed for SARS-CoV-2 detection. Herein, we report a portable microfluidic-based integrated detection-analysis system for SARS-CoV-2 nucleic acids detection directly from saliva samples. The saliva cartridge is self-contained and capable of microfluidic evaluation of saliva, from heating, mixing with the primers to multiplex real-time quantitative polymerase chain reaction, detecting SARS-CoV-2 with different primer sets and internal control. The approach has a detection sensitivity of 1000 copies/mL of SARS-CoV-2 RNA or virus, with consistency and automation, from saliva sample-in to result-out.

20.
Electrophoresis ; 31(21): 3510-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20931618

RESUMO

The microfluidic integration of an entire DNA analysis workflow on a fully integrated miniaturized instrument is reported using lab-on-a-chip automation to perform DNA fingerprinting compatible with CODIS standard relevant to the forensic community. The instrument aims to improve the cost, duration, and ease of use to perform a "sample-to-profile" analysis with no need for human intervention. The present publication describes the operation of the three major components of the system: the electronic control components, the microfluidic cartridge and CE microchip, and the optical excitation/detection module. Experimental details are given to characterize the level of performance, stability, reliability, accuracy, and sensitivity of the prototype system. A typical temperature profile from a PCR amplification process and an electropherogram of a commercial size standard (GeneScan 500™, Applied Biosystems) separation are shown to assess the relevance of the instrument to forensic applications. Finally, we present a profile from an automated integrated run where lysed cells from a buccal swab were introduced in the system and no further human intervention was required to complete the analysis.


Assuntos
Eletroforese Capilar/métodos , Técnicas Analíticas Microfluídicas/instrumentação , Repetições de Microssatélites , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA/instrumentação , Bochecha , DNA/química , DNA/isolamento & purificação , Genética Forense/métodos , Humanos , Técnicas Analíticas Microfluídicas/métodos , Mucosa Bucal/citologia , Reprodutibilidade dos Testes , Análise de Sequência de DNA/métodos , Temperatura
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