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1.
Front Vet Sci ; 9: 897687, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35754537

RESUMO

The goal of the current study was to identify ways to increase awareness and engagement in kitten fostering programs (KFPs) among residents of areas with a high intake of kittens to animal shelters in Southern California (i.e., Los Angeles County). Specifically, we aimed to understand residents': (1) awareness of KFPs and kitten overpopulation issues, (2) interest in fostering kittens with an animal welfare organization, (3) concerns about fostering, (4) perceived ability to meet common KFP requirements, and (5) perceptions of potential KFP marketing/messaging and communication methods. Participants included 283, predominantly Hispanic/Latinx adults aged 18 years or older who resided in Los Angeles County and who lived in one of 12 zip codes with a high rate of kitten shelter intake. Survey results indicated that more than one quarter of participants had engaged in fostering on their own without an animal shelter or rescue program. One-third of the total sample, and more than two-thirds of participants who had already fostered cats and kittens on their own, were open to fostering kittens in partnership with an animal shelter. A majority of individuals who were interested in fostering had not seen advertising for fostering programs; Spanish-language participants were significantly less likely than expected to have encountered program advertisements. The most prevalent concerns about fostering in our sample were centered on the time (79%), cost (78%), and space (77%) required to engage in fostering. Text, email, social media, and mail were among the most preferred methods for marketing and communication, with some variation between Spanish and English language respondents. Opportunities for increasing engagement included, but were not limited to, improving the promotion of program advertisements using animal-welfare and cost-focused messaging approaches and improving the dissemination and marketing of Spanish-language materials. Providing community members with realistic expectations of the time, resources, and support they will get from animal welfare organizations may improve engagement in KFPs, as well as identifying alternative resources and supports (e.g., transportation, in-home veterinary visits) to assist community members in serving animals in their community.

2.
Planta ; 253(2): 62, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33544238

RESUMO

MAIN CONCLUSION: Excited state lifetime-based separation of fluorophore-tagged antibiotic conjugate emission from the spectrally broad plant autofluorescence enables in planta tracking of the translocation of systemic cargo such as antibiotics via fluorescence lifetime imaging. The efficacy of antibiotic treatments in citrus crops is uncertain due to mixed results from in-field experiments and a lack of study on their systemic movement. As of yet there has been an inability to track treatments using traditional fluorescence microscopy due to treatments having little fluorescence characteristics, and signal convolution due to plant autofluorescence. In this study, we used streptomycin sulfate, a commercially available antibiotic, and conjugated it to a modified tris(bipyridine) ruthenium (II) chloride, a dye with an excited state lifetime magnitudes higher than other commonly used organic fluorescent probes. The resultant is a fluorescence lifetime imaging (FLIM) trackable antibiotic conjugate, covalently attached via an amide linkage that is uniquely distinguishable from plant autofluorescence. Characterization of the fluorescent antibiotic conjugate showed no mitigation of excited state lifetime, and a distinct IR peak not found in any synthetic components. Subsequent tracking using FLIM in citrus tissue was achieved, with identification of movement through citrus plant vasculature via tissue localization in xylem and phloem. Results indicated upwards systemic movement of the conjugate in both xylem and phloem after 48 h of incubation. However, the conjugate failed to move down towards the root system of the plant by 168 h. Mechanistically, it is likely that xylem contributes heavily in the translocation of the conjugate upwards; however, phloem led flow due to growth changes could act as a contributor. This proof-of-concept sets groundwork for subsequent studies regarding antibiotic localization and movement in citrus.


Assuntos
Antibacterianos/farmacocinética , Citrus/efeitos dos fármacos , Microscopia de Fluorescência , Imagem Óptica , Floema , Xilema , Corantes Fluorescentes
3.
J Phys Chem A ; 121(1): 24-30, 2017 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-27996263

RESUMO

We present rate constants and product branching ratios for the reactions of FeOx+ (x = 0-4) with ozone at 500 K. Fe+ is observed to react with ozone at the collision rate to produce FeO+ + O2. The FeO+ in turn reacts with ozone at the collision rate to yield both Fe+ and FeO2+ product channels. Ions up to FeO4+ display similar reactivity patterns. Three-body clustering reactions with O2 prevent us from measuring accurate rate constants at 300 K although the data do suggest that the efficiency is also high. Therefore, it is probable that little to no temperature dependence exists over this range. Implications of our measurements to the regulation of atmospheric iron and ozone are discussed. Density functional calculations on the reaction of Fe+ with ozone show no substantial kinetic barriers to make the FeO+ + O2 product channel, which is consistent with the reaction's efficiency. While a pathway to make FeO2+ + O is also found to be barrierless, our experiments indicate no primary FeO2+ formation for this reaction.

4.
PLoS One ; 9(2): e87675, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24498351

RESUMO

Over the last two decades, cell surface proteases belonging to the type II transmembrane serine protease (TTSP) family have emerged as important enzymes in the mammalian degradome, playing critical roles in epithelial biology, regulation of metabolic homeostasis, and cancer. Human airway trypsin-like protease 5 (HATL5) is one of the few family members that remains uncharacterized. Here we demonstrate that HATL5 is a catalytically active serine protease that is inhibited by the two Kunitz type serine protease inhibitors, hepatocyte growth factor activator inhibitor (HAI)-1 and 2, as well as by serpinA1. Full-length HATL5 is localized on the cell surface of cultured mammalian cells as demonstrated by confocal microscopy. HATL5 displays a relatively restricted tissue expression profile, with both transcript and protein present in the cervix, esophagus, and oral cavity. Immunohistochemical analysis revealed an expression pattern where HATL5 is localized on the cell surface of differentiated epithelial cells in the stratified squamous epithelia of all three of these tissues. Interestingly, HATL5 is significantly decreased in cervical, esophageal, and head and neck carcinomas as compared to normal tissue. Analysis of cervical and esophageal cancer tissue arrays demonstrated that the squamous epithelial cells lose their expression of HATL5 protein upon malignant transformation.


Assuntos
Membrana Celular/metabolismo , Epitélio/metabolismo , Proteínas de Membrana/metabolismo , Neoplasias/enzimologia , Serina Endopeptidases/metabolismo , Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Sequência de Aminoácidos , Animais , Células COS , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/genética , Epitélio/patologia , Neoplasias Esofágicas/enzimologia , Neoplasias Esofágicas/genética , Feminino , Perfilação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Imuno-Histoquímica , Proteínas de Membrana/genética , Dados de Sequência Molecular , Neoplasias Bucais/enzimologia , Neoplasias Bucais/genética , Neoplasias/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina Endopeptidases/genética , Neoplasias da Língua/enzimologia , Neoplasias da Língua/genética , Neoplasias do Colo do Útero/enzimologia , Neoplasias do Colo do Útero/genética
5.
Cell Tissue Res ; 351(2): 245-53, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22350849

RESUMO

The type II transmembrane serine protease matriptase has an essential role in the integrity and function of multiple epithelial tissues. In the epidermis, matriptase activates the glycosylphosphatidylinositol (GPI) anchored membrane serine protease prostasin to initiate a proteolytic cascade that is required for the development of the stratum corneum barrier function. Accordingly, mice deficient for matriptase phenocopy mice deficient for epidermal prostasin and present with impaired corneocyte differentiation, imparied lipid matrix formation, loss of profilaggrin processing and loss of tight junction formation and function. Together, these defects lead to a compromised epidermal barrier and result in fatal dehydration during the neonatal period. Proteolytic activity of the matriptase-prostasin cascade is regulated in the epidermis via inhibition by the Kunitz-type serine protease inhibitor hepatocyte growth factor activator inhibitor-1 (HAI-1). Importantly, targeted post-natal ablation of matriptase in mice perturbs the function of multiple adult tissues, indicating an ongoing requirement for matriptase proteolysis in the maintenance of diverse types of epithelia. Impaired matriptase proteolytic activity has been linked to human Autosomal Recessive Icthyosis with Hypotrichosis (ARIH), whereas aberrant matriptase activity has been implicated in Netherton's Syndrome. This review will summarize information pertaining to the role of matriptase in epithelial biology and will discuss recent advancements in our understanding of how matriptase activity is regulated and the down-stream effectors of matriptase proteolysis.


Assuntos
Células Epiteliais/citologia , Células Epiteliais/metabolismo , Epitélio/metabolismo , Epitélio/patologia , Serina Endopeptidases/metabolismo , Animais , Diferenciação Celular/fisiologia , Células Epiteliais/enzimologia , Células Epiteliais/patologia , Epitélio/enzimologia , Humanos
7.
J Biol Chem ; 283(41): 27810-27819, 2008 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-18678867

RESUMO

The life span of model organisms can be modulated by environmental conditions that influence cellular metabolism, oxidation, or DNA integrity. The yeast nicotinamidase gene pnc1 was identified as a key transcriptional target and mediator of calorie restriction and stress-induced life span extension. PNC1 is thought to exert its effect on yeast life span by modulating cellular nicotinamide and NAD levels, resulting in increased activity of Sir2 family class III histone deacetylases. In Caenorhabditis elegans, knockdown of a pnc1 homolog was shown recently to shorten the worm life span, whereas its overexpression increased survival under conditions of oxidative stress. The function and regulation of nicotinamidases in higher organisms has not been determined. Here, we report the identification and biochemical characterization of the Drosophila nicotinamidase, D-NAAM, and demonstrate that its overexpression significantly increases median and maximal fly life span. The life span extension was reversed in Sir2 mutant flies, suggesting Sir2 dependence. Testing for physiological effectors of D-NAAM in Drosophila S2 cells, we identified oxidative stress as a primary regulator, both at the transcription level and protein activity. In contrast to the yeast model, stress factors such as high osmolarity and heat shock, calorie restriction, or inhibitors of TOR and phosphatidylinositol 3-kinase pathways do not appear to regulate D-NAAM in S2 cells. Interestingly, the expression of D-NAAM in human neuronal cells conferred protection from oxidative stress-induced cell death in a sirtuin-dependent manner. Together, our findings establish a life span extending the ability of nicotinamidase in flies and offer a role for nicotinamide-modulating genes in oxidative stress regulated pathways influencing longevity and neuronal cell survival.


Assuntos
Longevidade/fisiologia , Modelos Biológicos , Neurônios/enzimologia , Nicotinamidase/biossíntese , Estresse Oxidativo/fisiologia , Transcrição Gênica/fisiologia , Animais , Células COS , Restrição Calórica , Sobrevivência Celular/fisiologia , Chlorocebus aethiops , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Resposta ao Choque Térmico/fisiologia , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Humanos , Mutação , Nicotinamidase/genética , Pressão Osmótica , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Sirtuínas/genética , Sirtuínas/metabolismo
8.
J Strength Cond Res ; 21(4): 1067-71, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18076250

RESUMO

In practice, the Bruce protocol is the most commonly used treadmill protocol to assess maximal oxygen consumption (V(.-)O2max). It has been suggested that a running protocol (e.g., Astrand) may elicit a comparatively higher V(.-)O2max and different cardiorespiratory responses when applied to moderately trained runners. Thus, the purpose of this study was to compare V(.-)O2max and other cardiorespiratory responses as elicited by the standard Bruce and a modified Astrand treadmill protocol in moderately trained runners. Fifteen women (age = 21 years, height = 171.5 cm, weight = 63 kg, and body fat = 18%) and 15 men (age = 26 years, height = 177 cm, weight = 72 kg, and body fat = 9%) who were moderately trained runners completed a standard Bruce and modified Astrand protocol (random order), separated by approximately 7 days. Heart rate, Borg ratings of perceived exertion, blood pressure, and pulmonary gas exchange variables were measured during the exercise tests using standard laboratory procedures. This study revealed V(.-)O2max values between the Bruce protocol (51.3 +/- 11.6 ml x kg(-1) x min(-1)) and modified Astrand (51.5 +/- 10.9 ml x kg(-1) x min(-1)) were not significantly different in either the men or the women. However, the Bruce protocol elicited significantly higher maximum treadmill time in men and maximum respiratory exchange ratio (RERmax) and maximum minute ventilation (VEmax) values in both genders. Conversely, the modified Astrand elicited a higher HRmax. These data suggest that V(.-)O2max in both moderately trained men and women runners is independent of treadmill protocol despite differences in HRmax, RERmax, and VEmax.


Assuntos
Protocolos Clínicos , Teste de Esforço/métodos , Exercício Físico/fisiologia , Consumo de Oxigênio/fisiologia , Adulto , Desempenho Atlético/fisiologia , Estudos Cross-Over , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Corrida/fisiologia , Fatores Sexuais
9.
Environ Sci Technol ; 40(18): 5704-9, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-17007129

RESUMO

Bacterium o-17, a microorganism capable of the ortho dechlorination of 2,3,5,6-polychlorinated biphenyl (PCB), is a member of a sediment-free, nonmethanogenic mixed culture. The culture was examined for the ability to dechlorinate 26 PCB congeners, 12 chlorobenzenes (CBZs), and 6 chlorinated ethenes (CEs). Eight of the PCBs and 4 of the CBZs were dechlorinated including single-flanked ortho PCB chlorines, but double-flanked chlorines of PCBs and CBZs were preferentially dechlorinated. The dechlorination of three of the PCBs (2,3,4,5,6-, 2,3,4,6-, and 2,3,5,6-PCB), three of the CBZs (hexa-, penta-, and 1,2,3-CBZ), and PCE could be sustained for three or more sequential transfers of the bacterial community. Two PCBs (2,3,4- and 2,3,5-PCB), two CBZs (1,2,3,5- and 1,2,4,5-CBZ), and trichloroethene were dechlorinated only when a more extensively chlorinated parent compound was present. Aroclor 1260 and 2,4,6-PCB, not dechlorinated by the culture, inhibited the dechlorination of 2,3,5,6-PCB. Within the culture only bacterium o-17 was linked to dechlorination by PCR-DGGE analysis, confirming that this dehalogenating species was the catalyst for the dechlorination of the compounds tested. The microorganism is capable of dechlorinating several different congeners of PCBs, CBZs, and CEs, and it remains a rare example of an ortho-PCB dechlorinator. However, its limited ability to dechlorinate more extensively chlorinated congeners and Aroclor plus the inhibitory effects of some PCB congeners upon the bacterium is consistent with the observed infrequency of this reaction in the environment. An assessment of bioremediation potential of this microorganism in situ will require a greater understanding of the synergistic, cometabolic and competitive interactions of PCB dechlorinating microbial communities.


Assuntos
Bactérias/metabolismo , Poluentes Ambientais/metabolismo , Bifenilos Policlorados/metabolismo , Clorobenzenos/química , Clorobenzenos/metabolismo , Eletroforese em Gel de Poliacrilamida/métodos , Poluentes Ambientais/química , Etilenos/química , Etilenos/metabolismo , Bifenilos Policlorados/química , Reação em Cadeia da Polimerase/métodos
10.
Environ Sci Technol ; 39(8): 2631-5, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15884359

RESUMO

Polychlorinated biphenyls (PCBs) and chlorinated ethenes (CEs) are known to pollute sediment, soil, and groundwater. The anaerobic dechlorination of these compounds is an integral part of their biodegradation in polluted environments. We report for the first time the dechlorination of tetrachloroethene (PCE) and trichloroethene (TCE) by bacterium DF-1. This PCB and chlorobenzene dechlorinating bacterium dechlorinated PCE to TCE, which was then converted into trans-1,2-dichloroethene (trans-DCE) and cis-1,2-dichloroethene (cis-DCE). The ratio of trans-DCE to cis-DCE produced by the culture had a range of 1.2-1.7. Bacterium DF-1 has been enriched in co-culture with a desulfovibrio-like microorganism. PCR-denaturing gradient gel electrophoresis (PCR-DGGE) analysis of the 16S rRNA genes of the co-culture demonstrated that DF-1 was enriched during the dechlorination of PCE, PCB, and chlorobenzene. DF-1 was not detected in the absence of PCE dechlorination and the desulfovibrio-like organism, isolated in pure culture, did not dechlorinate PCE. This is the first identification of a microorganism capable of producing high amounts of trans-DCE from PCE and indicates that microorganisms such as DF-1 are a possible biological source of trans-DCE in the environment.


Assuntos
Bactérias/metabolismo , Cloro/química , Dicloroetilenos/metabolismo , Bifenilos Policlorados/metabolismo , Tetracloroetileno/metabolismo , Anaerobiose , Biodegradação Ambiental , Técnicas de Cocultura , Eletroforese , Poluentes Ambientais/metabolismo , Methylococcaceae , Oxirredução , RNA Ribossômico 16S/análise , Microbiologia do Solo , Estereoisomerismo
11.
Anesthesiology ; 97(4): 875-81, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12357153

RESUMO

BACKGROUND: Acute aortic occlusion in vascular surgery patients abruptly increases arterial resistance and blood pressure, which, in turn, makes subsequent volume expansion during cross-clamp application difficult. The use of vasodilatory drugs or volatile anesthetic agents to attenuate this response may have persistent detrimental effects after clamp removal. Another potential therapy that produces rapid effects on myocardial loading conditions is positive end-expiratory pressure (PEEP). In a porcine model of acute aortic clamping, the hemodynamic consequences of 15 cm H(2)O PEEP with and without plasma volume expansion were studied.(2) METHODS: Forty anesthetized pigs underwent 30-min occlusion of the abdominal aorta 1 cm above the origin of the celiac artery. Animals were randomly divided into four treatment groups (n = 10 each) to receive 15 cm H(2)O PEEP or zero end-expiratory pressure (ZEEP) with or without plasma volume expansion using 6% hetastarch (10 ml/kg) during cross-clamp application. Mean aortic pressure was measured with a transducer-tipped catheter placed in the ascending aorta; stroke volume was calculated using thermodilution cardiac output. End-expiratory pressure was discontinued upon aortic declamping, and animals were studied over the ensuing 30-min period. RESULTS: Aortic occlusion doubled systemic vascular resistance in all groups. Mean aortic blood pressure increased significantly in both ZEEP groups at 1 and 5 min but not in animals treated with 15 cm H(2)O PEEP. The application of PEEP with aortic cross-clamping reduced cardiac output and stroke volume by nearly 50%. Cardiac output and stroke volume increased after volume expansion regardless of end-expiratory pressure. After aortic declamping, aortic blood pressure decreased in all groups but was significantly greater in the PEEP + volume group than in either ZEEP group. Similarly, 5 min after declamping, stroke volume was greatest in the PEEP + volume animals. CONCLUSIONS: Fifteen cm H(2)O PEEP reduces the hypertensive response to acute aortic occlusion and allows concomitant volume expansion. Consequently, stroke volume and blood pressure are better maintained after clamp removal in PEEP + volume animals. The use of PEEP during acute aortic occlusion in patients may allow rapid control of loading conditions to attenuate systemic hypertension while permitting simultaneous volume expansion.


Assuntos
Aorta Torácica/fisiologia , Hemodinâmica/fisiologia , Respiração com Pressão Positiva , Animais , Volume Sanguíneo/fisiologia , Débito Cardíaco/fisiologia , Constrição , Feminino , Substitutos do Plasma/uso terapêutico , Mecânica Respiratória/fisiologia , Volume Sistólico/fisiologia , Suínos , Resistência Vascular/fisiologia
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