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1.
Biol Open ; 12(12)2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-38156711

RESUMO

Spring conditions, especially in temperate regions, may fluctuate abruptly and drastically. Environmental variability can expose organisms to temperatures outside of their optimal thermal ranges. For ectotherms, sudden changes in temperature may cause short- and long-term physiological effects, including changes in respiration, morphology, and reproduction. Exposure to variable temperatures during active development, which is likely to occur for insects developing in spring, can cause detrimental effects. Using the alfalfa leafcutting bee, Megachile rotundata, we aimed to determine if oxygen consumption could be measured using a new system and to test the hypothesis that female and male M. rotundata have a thermal performance curve with a wide optimal range. Oxygen consumption of M. rotundata pupae was measured across a large range of temperatures (6-48°C) using an optical oxygen sensor in a closed respirometry system. Absolute and mass-specific metabolic rates were calculated and compared between bees that were extracted from their brood cells and those remaining in the brood cell to determine whether pupae could be accurately measured inside their brood cells. The metabolic response to temperature was non-linear, which is an assumption of a thermal performance curve; however, the predicted negative slope at higher temperatures was not observed. Despite sexual dimorphism in body mass, sex differences only occurred in mass-specific metabolic rates. Higher metabolic rates in males may be attributed to faster development times, which could explain why there were no differences in absolute metabolic rate measurements. Understanding the physiological and ecological effects of thermal environmental variability on M. rotundata will help to better predict their response to climate change.


Assuntos
Medicago sativa , Metamorfose Biológica , Abelhas , Feminino , Masculino , Animais , Temperatura , Pupa/fisiologia , Temperatura Alta
2.
J Org Chem ; 88(15): 10655-10661, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37439486

RESUMO

Reported herein are the synthesis and characterization of BODIPYs bearing heterocycles at boron. To synthesize this series, various chalcogenophenes (furan, thiophene, selenophene, and tellurophene) were lithiated and then used as nucleophiles to attack the boron center of a parent F-BODIPY. Compounds in the series were compared with respect to their photophysical and structural properties, and trends were discussed. By virtue of the "heavy atom effect", as the mass of the heterocycle appended to the BODIPY core increases, compounds exhibit a higher singlet oxygen quantum yield. The BODIPY with tellurophene at boron exhibits the highest quantum yield (ΦΔ = 0.68) in the series and reduced emission (Φf = 0.01).

3.
Cells ; 12(11)2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37296648

RESUMO

OBJECTIVES: Intra-abdominal sepsis is commonly diagnosed in the surgical population and remains the second most common cause of sepsis overall. Sepsis-related mortality remains a significant burden in the intensive care unit despite advances in critical care. Nearly a quarter of the deaths in people with heart failure are caused by sepsis. We have observed that overexpression of mammalian Pellino-1 (Peli1), an E3 ubiquitin ligase, causes inhibition of apoptosis, oxidative stress, and preservation of cardiac function in a myocardial infarction model. Given these manifold applications, we investigated the role of Peli1 in sepsis using transgenic and knockout mouse models specific to this protein. Therefore, we aimed to explore further the myocardial dysfunction seen in sepsis through its relation to the Peli 1 protein by using the loss of function and gain-of-function strategy. METHODS: A series of genetic animals were created to understand the role of Peli1 in sepsis and the preservation of heart function. Wild-type, global Peli1 knock out (Peli1-/-), cardiomyocyte-specific Peli1 deletion (CP1KO), and cardiomyocyte-specific Peli1 overexpressing (alpha MHC (αMHC) Peli1; AMPEL1Tg/+) animals were divided into sham and cecal ligation and puncture (CLP) surgical procedure groups. Cardiac function was determined by two-dimensional echocardiography pre-surgery and at 6- and 24-h post-surgery. Serum IL-6 and TNF-alpha levels (ELISA) (6 h), cardiac apoptosis (TUNEL assay), and Bax expression (24 h) post-surgery were measured. Results are expressed as mean ± S.E.M. RESULTS: AMPEL1Tg/+ prevents sepsis-induced cardiac dysfunction assessed by echocardiographic analysis, whereas global and cardiomyocyte-specific deletion of Peli1 shows significant deterioration of cardiac functions. Cardiac function was similar across the sham groups in all three genetically modified mice. ELISA assay displayed how Peli 1 overexpression decreased cardo-suppressive circulating inflammatory cytokines (TNF-alpha, IL-6) compared to both the knockout groups. The proportion of TUNEL-positive cells varied according to Peli1 expression, with overexpression (AMPEL1Tg/+) leading to a significant reduction and Peli1 gene knockout (Peli1-/- and CP1KO) leading to a significant increase in their presence. A similar trend was also observed with Bax protein expression. The improved cellular survival associated with Peli1 overexpression was again shown with the reduction of oxidative stress marker 4-Hydroxy-2-Nonenal (4-HNE). CONCLUSION: Our results indicate that overexpression of Peli1 is a novel approach that not only preserved cardiac function but reduced inflammatory markers and apoptosis following severe sepsis in a murine genetic model.


Assuntos
Sepse , Fator de Necrose Tumoral alfa , Camundongos , Animais , Interleucina-6 , Miócitos Cardíacos , Inflamação/complicações , Sepse/complicações , Mamíferos , Proteínas Nucleares/genética , Ubiquitina-Proteína Ligases/genética
4.
ACS Omega ; 7(39): 35326-35330, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36211064

RESUMO

Gemini surfactants are composed of two hydrocarbon tails with corresponding polar headgroups, linked via a covalent spacer. The synthesis of these surfactants is a very active area of research due to their application as catalysts and other applied areas of study. The modification of green microwave techniques developed in our research on ionic liquids has resulted in the significant improvement of the synthesis of N,N'-bis(dimethylalkyl)-α,ω-alkanediammonium dibromide (m-s-m type) symmetrical gemini surfactants. This approach utilizes a remarkably more economical, green, and sustainable methodology for the production of symmetrical gemini surfactants that can be utilized in numerous commercial applications. The improved synthetic approach of these gemini surfactants has led to the characterization of their crystalline packing for the first time ever using X-ray crystallographic analysis.

5.
BMJ Case Rep ; 15(3)2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35236689

RESUMO

Caecal herniation through the foramen of Winslow is an uncommon presentation of internal hernia with an estimated overall incidence of 0.02%. Even rarer still is a caecal volvulus strangulated in the lesser sac, a surgical emergency seldom described in the literature. A woman in her 70s presented with a 1-day history of acute-onset right upper quadrant and epigastric pain associated with nausea and vomiting. Prompt CT imaging revealed caecal volvulus within a foramen of Winslow hernia. The diagnosis was confirmed by laparotomy. A right hemicolectomy was performed and the foraminal defect was closed. We identified eight case reports of this rare entity published within the last 30 years. Our patient was managed in a similar manner and recovered without complication, providing further guidance for the operative management of caecal volvulus in the foramen of Winslow.


Assuntos
Hérnia Abdominal , Volvo Intestinal , Ceco/cirurgia , Colectomia , Feminino , Hérnia/complicações , Hérnia Abdominal/cirurgia , Humanos , Hérnia Interna , Volvo Intestinal/complicações , Volvo Intestinal/diagnóstico por imagem , Volvo Intestinal/cirurgia
6.
Microvasc Res ; 141: 104311, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34999110

RESUMO

OBJECTIVES: In the United States, over 8.5 million people suffer from peripheral arterial disease (PAD). Previously we reported that Pellino-1(Peli1) gene therapy reduces ischemic damage in the myocardium and skin flaps in Flk-1 [Fetal Liver kinase receptor-1 (Flk-1)/ Vascular endothelial growth factor receptor-2/VEGFR2] heterozygous (Flk-1+/--) mice. The present study compares the angiogenic response and perfusion efficiency following hind limb ischemia (HLI) in, Flk-1+/- and, MAPKAPKINASE2 (MK2-/-) knockout (KO) mice to their control wild type (WT). We also demonstrated the use of Peli1 gene therapy to improve loss of function following HLI. STUDY DESIGN AND METHODS: Femoral artery ligation (HLI) was performed in both Flk-1+/- and MK2-/- mice along with their corresponding WT. Another set of Flk-1+/- and MK2-/- were injected with either Adeno-LacZ (Ad.LacZ) or Adeno-Peli1 (Ad.Peli1) after HLI. Hind limb perfusion was assessed by laser doppler imaging at specific time points. A standardized scoring scale is used to quantify the extent of ischemia. Histology analysis performed includes capillary density, fibrosis, pro-angiogenic and anti-apoptotic proteins. RESULTS: Flk-1+/- and MK2-/- had a slower recovery of perfusion efficiency in the ischemic limbs than controls. Both Flk-1+/- and MK2-/- KO mice showed decreased capillary density and capillary myocyte ratios with increased fibrosis than their corresponding wild types. Ad.Peli1 injected ischemic Flk-1+/- limb showed improved perfusion, increased capillary density, and pro-angiogenic molecules with reduced fibrosis compared to Ad.LacZ group. No significant improvement in perfusion was observed in MK2-/- ischemic limb after Ad. Peli1 injection. CONCLUSION: Deletion of Flk-1 and MK2 impairs neovascularization and perfusion following HLI. Treatment with Ad. Peli1 results in increased angiogenesis and improved perfusion in Flk-1+/- mice but fails to rectify perfusion in MK2 KO mice. Overall, Peli1 gene therapy is a promising candidate for the treatment of PAD.


Assuntos
Doença Arterial Periférica , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Animais , Modelos Animais de Doenças , Fibrose , Terapia Genética/métodos , Membro Posterior/irrigação sanguínea , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Isquemia/genética , Isquemia/patologia , Isquemia/terapia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neovascularização Fisiológica , Proteínas Nucleares/genética , Perfusão , Doença Arterial Periférica/genética , Doença Arterial Periférica/terapia , Proteínas Serina-Treonina Quinases , Ubiquitina-Proteína Ligases , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
7.
ACS Med Chem Lett ; 12(12): 1925-1931, 2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34917256

RESUMO

The synthesis and characterization of the first BODIPY appended to the five-membered heterocylic tellurophene [Te] moiety is reported. By incorporating tellurophene at the meso position, the tellurophene-appended boron-dipyrromethene dye (BODIPY) acts as a multimodal agent, becoming a potent photosensitizer with a mass cytometry tag. To synthesize the compound, we developed a method to enable late-stage Suzuki-Miyaura coupling by preparing and isolating tellurophene-2-BPin in a one-step procedure from the parent tellurophene. Coupling to a meso-substituted BODIPY functionalized with a pendant aryl bromide provides the desired tellurophene-appended BODIPY. This compound demonstrated a singlet oxygen quantum yield of 0.26 ± 0.01 and produced a light dose-dependent cytotoxicity with nanomolar IC50 values against 2D cultured HeLa cells and high efficacy against 3D cultured HeLa tumor spheroids, proving to be a strong photosensitizer. The presence of the tellurophene moiety could be detected using mass cytometry, thus showcasing the ability of a tellurophene-appended BODIPY as a novel photodynamic-therapy-mass-cytometry theranostic agent.

8.
Int J Pharm ; 597: 120236, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33539996

RESUMO

Despite recent advancements, mortality due to coronary heart disease (CHD) remains high. Recently, the use of tissue-engineered grafts and scaffolds has emerged as a candidate for supporting the myocardium after an ischemic event. Resveratrol is a naturally occurring plant-based non-flavonoid polyphenolic compound found in many natural foods, including grapes and red wine. We embedded resveratrol in a polycaprolactone (PCL) scaffold and evaluated the cardio-therapeutic effects in a murine model of myocardial infarction (MI), with animals being grouped into Sham (S), Myocardial Infarction (MI), MI + PCL, and MI + PCL-Resveratrol (MI + PCL-R). After 4 and 8 weeks, echocardiography was performed to assess ejection fraction (EF) and fractional shortening (FS), which was followed by immunohistochemistry and immunofluorescence analysis at 8 weeks. The MI + PCL-R group showed a significant improvement in EF and FS compared with the MI + PCL group at 4 and 8-weeks post-surgery. PCL-R scaffolds treated hearts revealed decreased inflammatory cell infiltration, improved collagen extracellular matrix (ECM) secretion and blood vessel network formation following MI. The immunofluorescence analysis revealed resveratrol-loaded scaffolds promote increased expression of cTnT, Cx-43, Trx-1, and VEGF proteins. This study reports resveratrol-mediated rescue of ischemic myocardium when delivered through a biodegradable polymeric scaffold system after MI.


Assuntos
Infarto do Miocárdio , Fator A de Crescimento do Endotélio Vascular , Animais , Camundongos , Infarto do Miocárdio/tratamento farmacológico , Miocárdio , Regeneração , Resveratrol , Tiorredoxinas
9.
Cryobiology ; 99: 114-121, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33279509

RESUMO

The development of cryopreservation protocols for Anopheles gambiae could significantly improve research and control efforts. Cryopreservation of any An. gambiae life stage has yet to be successful. The unique properties of embryos have proven to be resistant to any practical cryoprotectant loading. Therefore, we have chosen to investigate early non-feeding first instar larvae as a potential life stage for cryopreservation. In order to determine an appropriate cryoprotective compound, larvae were treated with progressively better glass-forming cryoprotective mixtures. Toxicity evaluation in combination with calorimetry-based water content and supercooling point depression assessments were used to determine the cryoprotectants that could be used for cryostorage of viable larvae. Approximately 35-75% of the larvae were viable after reasonably high osmotic and biochemical challenge. This study provides ample evidence for an active osmoregulatory response in the Anopheles larvae to counter the permeation of cryoprotectants from the surrounding medium. The data show a strong correlation between the larval mortality and water content, indicating an osmoregulatory crisis in the larva due to certain cryoprotectants such as the higher concentrations of ethane diol (ED). The observations also indicate that the ability of the larvae to regulate permeation and water balance ceases at or within 20 min of cryoprotectant exposure, but this is strongly influenced by the treatment temperature. Among the compound cryoprotectants tested, 25% ED + 10% dimethyl sulfoxide (DMSO) and 40% ED + 0.5 M trehalose seem to present a compromise between viability, larval water content, supercooling point depression, and glass forming abilities.


Assuntos
Anopheles/fisiologia , Crioprotetores/farmacologia , Animais , Anopheles/efeitos dos fármacos , Criopreservação/métodos , Larva/efeitos dos fármacos
10.
Basic Res Cardiol ; 115(4): 45, 2020 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-32537701

RESUMO

INTRODUCTION: In the present study, we aimed to explore the functional role of Pellino-1 (Peli1) in inducing neovascularization after myocardial infarction (MI) and hindlimb ischemia (HLI) using Peli1 global knockout mice (Peli1-/-). Recently we have shown that Peli1, an E3 ubiquitin ligase, induce angiogenesis and improve survivability, with decreased necrosis of ischemic skin flaps. METHODS: Peli1fl/fl and Peli1-/- mice were subjected to either permanent ligation of the left anterior descending coronary artery (LAD) or sham surgery (S). Tissues from the left ventricular risk area were collected at different time points post-MI. In addition, Peli1fl/fl and Peli1-/- mice were also subjected to permanent ligation of the right femoral artery followed by motor function scores, Doppler analysis for blood perfusion and immunohistochemical analysis. RESULTS: Global Peli1 knockout exacerbated myocardial dysfunction, 30 and 60 days after MI compared to wild type (WT) mice as measured by echocardiogram. In addition, Peli1-/- mice also showed decreased motor function scores and perfusion ratios compared with Peli1fl/fl mice 28 days after the induction of HLI. The use of Peli1 in adenoviral gene therapy following HLI in CD1 mice improved the perfusion ratio at 28 days compared to Ad.LacZ-injected mice. CONCLUSION: These results suggest new insights into the protective role of Peli1 on ischemic tissues and its influence on survival signaling.


Assuntos
Isquemia/metabolismo , Infarto do Miocárdio/metabolismo , Neovascularização Fisiológica/fisiologia , Proteínas Nucleares/metabolismo , Estresse Oxidativo/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Animais , Proteína 3 com Repetições IAP de Baculovírus/metabolismo , Sobrevivência Celular/fisiologia , Modelos Animais de Doenças , Regulação para Baixo , Artéria Femoral/cirurgia , Ligadura , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo
11.
Proc Natl Acad Sci U S A ; 117(4): 2180-2186, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31932424

RESUMO

Gravity is one of the most ubiquitous environmental effects on living systems: Cellular and organismal responses to gravity are of central importance to understanding the physiological function of organisms, especially eukaryotes. Gravity has been demonstrated to have strong effects on the closed cardiovascular systems of terrestrial vertebrates, with rapidly responding neural reflexes ensuring proper blood flow despite changes in posture. Invertebrates possess open circulatory systems, which could provide fewer mechanisms to restrict gravity effects on blood flow, suggesting that these species also experience effects of gravity on blood pressure and distribution. However, whether gravity affects the open circulatory systems of invertebrates is unknown, partly due to technical measurement issues associated with small body size. Here we used X-ray imaging, radio-tracing of hemolymph, and micropressure measurements in the American grasshopper, Schistocerca americana, to assess responses to body orientation. Our results show that during changes in body orientation, gravity causes large changes in blood and air distribution, and that body position affects ventilation rate. Remarkably, we also found that insects show similar heart rate responses to body position as vertebrates, and contrasting with the classic understanding of open circulatory systems, have flexible valving systems between thorax and abdomen that can separate pressures. Gravitational effects on invertebrate cardiovascular and respiratory systems are likely to be widely distributed among invertebrates and to have broad influence on morphological and physiological evolution.


Assuntos
Gafanhotos/fisiologia , Gravitação , Adaptação Fisiológica , Animais , Pressão Sanguínea , Tamanho Corporal , Fenômenos Fisiológicos Cardiovasculares , Gafanhotos/crescimento & desenvolvimento , Fenômenos Fisiológicos Respiratórios
12.
South Med J ; 112(8): 438-443, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31375841

RESUMO

OBJECTIVES: Urinary tract infections (UTIs) caused by extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae are resistant to many conventional therapies, including third-generation cephalosporins. Carbapenems are considered first-line agents for ESBL infections, but their use is associated with increased multidrug resistance and should be reserved when absolutely necessary. Because of the increased rates of UTIs caused by ESBL-producing organisms and incidence of carbapenem resistance, safe and effective alternatives to carbapenems are needed. This study was conducted to evaluate the outcomes associated with the treatment of ESBL UTIs with noncarbapenem antibiotics. METHODS: A retrospective cohort study of adults with ESBL UTIs was conducted at a community hospital. Patients were categorized as those receiving definitive carbapenem therapy and those receiving definitive noncarbapenem therapy. Calculated measurements included infection-related mortality, length of hospital stay, and duration of definitive antibiotic therapy. Microbiological failure was assessed as a secondary outcome. Data on the safety of antibiotic therapy were not collected. P < 0.05 was considered significant. RESULTS: Fifty patients met inclusion criteria for the study, divided evenly between the two cohorts. No statistical differences were observed for length of hospital stay (P = 0.601), duration of therapy (P = 0.398), or rate of microbiological failure between the groups (P = 0.115). CONCLUSIONS: Noncarbapenems did not demonstrate significant differences compared with carbapenems in the treatment of adults with ESBL UTIs. In certain patient populations, noncarbapenems that demonstrate in vitro activity may be appropriate for UTIs caused by ESBL-producing organisms.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Enterobacteriaceae/isolamento & purificação , Infecções Urinárias/tratamento farmacológico , beta-Lactamases/metabolismo , Idoso , Idoso de 80 Anos ou mais , Carbapenêmicos , Enterobacteriaceae/metabolismo , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Estudos Retrospectivos , Infecções Urinárias/microbiologia
13.
G3 (Bethesda) ; 9(9): 2989-2999, 2019 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-31311780

RESUMO

As the genetic bases to variation in anoxia tolerance are poorly understood, we used the Drosophila Genetics Reference Panel (DGRP) to conduct a genome-wide association study (GWAS) of anoxia tolerance in adult and larval Drosophila melanogaster Survival ranged from 0-100% in adults exposed to 6 h of anoxia and from 20-98% for larvae exposed to 1 h of anoxia. Anoxia tolerance had a broad-sense heritability of 0.552 in adults and 0.433 in larvae. Larval and adult phenotypes were weakly correlated but the anoxia tolerance of adult males and females were strongly correlated. The GWA identified 180 SNPs in adults and 32 SNPs in larvae associated with anoxia tolerance. Gene ontology enrichment analysis indicated that many of the 119 polymorphic genes associated with adult anoxia-tolerance were associated with ionic transport or immune function. In contrast, the 22 polymorphic genes associated with larval anoxia-tolerance were mostly associated with regulation of transcription and DNA replication. RNAi of mapped genes generally supported the hypothesis that disruption of these genes reduces anoxia tolerance. For two ion transport genes, we tested predicted directional and sex-specific effects of SNP alleles on adult anoxia tolerance and found strong support in one case but not the other. Correlating our phenotype to prior DGRP studies suggests that genes affecting anoxia tolerance also influence stress-resistance, immune function and ionic balance. Overall, our results provide evidence for multiple new potential genetic influences on anoxia tolerance and provide additional support for important roles of ion balance and immune processes in determining variation in anoxia tolerance.


Assuntos
Drosophila melanogaster/fisiologia , Genoma de Inseto/fisiologia , Oxigênio , Polimorfismo de Nucleotídeo Único , Animais , Animais Geneticamente Modificados , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Feminino , Técnicas de Silenciamento de Genes , Ontologia Genética , Estudo de Associação Genômica Ampla , Larva , Masculino , Fenótipo , Interferência de RNA
14.
Am J Physiol Regul Integr Comp Physiol ; 317(3): R442-R450, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31322917

RESUMO

Animals vary tremendously in their capacities to survive anoxia, and the mechanisms responsible are poorly understood. Adult Drosophila melanogaster are rapidly paralyzed and survive up to 12 h of anoxia, whereas larvae vigorously attempt escape but then die if anoxia exceeds 2 h. Here we use nuclear magnetic resonance methods to compare the metabolome of larvae and adult D. melanogaster under normoxic conditions and after various anoxic durations up to 1 h. Glucose increased during anoxia in both larvae and adults, so anoxic death by carbohydrate limitation is unlikely for either stage. Lactate and alanine were the primary anaerobic end products in both adults and larvae. During the first 30 min of anoxia, larvae accumulated anaerobic end products (predominately lactate) at a higher rate, suggesting that larvae may experience greater initial acid-base disruption during anoxic exposures. Adult Drosophila did not possess higher levels of putative protective metabolites; however, these increased during anoxia in adults and decreased in larvae. Metabolites that decreased during anoxia in larvae included mannitol, xylitol, glycerol, betaine, serine, and tyrosine, perhaps due to use as fuels, antioxidants, or binding to denatured proteins. Adults showed significant increases in glycine, taurine, and the polyols glycerol, mannitol, and xylitol, suggesting that adults upregulate protective metabolites to prevent damage. Our results suggest that lower initial metabolic demand due to paralytic hypometabolism and capacities to upregulate protective metabolites may assist the better anoxia tolerance of adult Drosophila.


Assuntos
Drosophila melanogaster/metabolismo , Metabolômica , Oxigênio/farmacologia , Animais , Metabolismo dos Carboidratos , Metabolismo Energético , Feminino , Larva , Nitrogênio , Oxigênio/metabolismo
15.
J Exp Biol ; 222(Pt 5)2019 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-30630963

RESUMO

When exposed to anoxia, insects rapidly go into a hypometabolic coma from which they can recover when exposed to normoxia again. However, prolonged anoxic bouts eventually lead to death in most insects, although some species are surprisingly tolerant. Anoxia challenges ATP, ion, pH and water homeostasis, but it is not clear how fast and to what degree each of these parameters is disrupted during anoxia, nor how quickly they recover. Further, it has not been investigated which disruptions are the primary source of the tissue damage that ultimately causes death. Here, we show, in the migratory locust (Locusta migratoria), that prolonged anoxic exposures are associated with increased recovery time, decreased survival, rapidly disrupted ATP and pH homeostasis and a slower disruption of ion ([K+] and [Na+]) and water balance. Locusts could not fully recover after 4 h of anoxia at 30°C, and at this point hemolymph [K+] was elevated 5-fold and [Na+] was decreased 2-fold, muscle [ATP] was decreased to ≤3% of normoxic values, hemolymph pH had dropped 0.8 units from 7.3 to 6.5, and hemolymph water content was halved. These physiological changes are associated with marked tissue damage in vivo and we show that the isolated and combined effects of hyperkalemia, acidosis and anoxia can all cause muscle tissue damage in vitro to equally large degrees. When locusts were returned to normoxia after a moderate (2 h) exposure of anoxia, ATP recovered rapidly (15 min) and this was quickly followed by recovery of ion balance (30 min), while pH recovery took 2-24 h. Recovery of [K+] and [Na+] coincided with the animals exiting the comatose state, but recovery to an upright position took ∼90 min and was not related to any of the physiological parameters examined.


Assuntos
Trifosfato de Adenosina/metabolismo , Íons/metabolismo , Locusta migratoria/fisiologia , Água/metabolismo , Anaerobiose , Animais , Feminino , Concentração de Íons de Hidrogênio , Masculino , Músculos/fisiologia
16.
Int J Pharm ; 558: 177-186, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30639221

RESUMO

The complete loss of dermal tissue due to ischemia is a serious challenge facing clinicians. Frequently, the failure of wound healing is due to ischemic conditions prevailing at the site of damaged tissue. Restoration of lost vasculature at the ischemic site can be achieved by supplementing proangiogenic stimuli through an engineered scaffold mimicking dermal extracellular matrix. Towards this objective, we have developed an electrospun scaffold loaded with the pro-angiogenic molecule resveratrol. The physical and chemical changes in the polymeric scaffold before and after loading of resveratrol were characterized using field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), coherence scanning interferometry (CSI) and X-ray diffraction (XRD). A sustained release of resveratrol from the scaffold was elucidated by UV-spectrophotometer analysis. The enhancement in cell-matrix interaction was studied using human umbilical vein endothelial cells (HUVECs) seeded on the scaffolds. The biocompatibility analysis of resveratrol loaded scaffolds was evaluated through a subcutaneous implantation study in mice. The therapeutic potential of resveratrol loaded scaffolds to accelerate tissue repair was analyzed in a full-thickness ischemic wound model in mice. Wound closure and H&E staining analysis showed rapid closure of ischemic wound area and re-epithelialization in resveratrol loaded scaffold treated groups compared to collagen and negative control groups. The immunostaining analysis further revealed the activation of thioredoxin-1 (Trx-1), heme oxygenase-1 (HO-1) mediated vascular endothelial growth factor (VEGF) signaling in resveratrol loaded scaffold treated group. The expression of Bcl-2 in healing wound edges post-treatment with resveratrol loaded scaffold confirmed the anti-apoptotic effect mediated by resveratrol. From this study, we explored a synergistic effect mediated by resveratrol and fibrous scaffolds to aid the ischemic wound healing process through effective vascularization.


Assuntos
Resveratrol/administração & dosagem , Tecidos Suporte , Cicatrização/efeitos dos fármacos , Animais , Células Cultivadas , Modelos Animais de Doenças , Feminino , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Isquemia/complicações , Masculino , Camundongos Endogâmicos C57BL , Resveratrol/química , Pele/efeitos dos fármacos , Fenômenos Fisiológicos da Pele/efeitos dos fármacos
17.
J Am Heart Assoc ; 7(18): e007601, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30371196

RESUMO

Background The present study demonstrates that the ubiquitin E3 ligase, Pellino-1 (Peli1), is an important angiogenic molecule under the control of vascular endothelial growth factor (VEGF) receptor 2/Flk-1. We have previously reported increased survivability of ischemic skin flap tissue by adenovirus carrying Peli1 (Ad-Peli1) gene therapy in Flk-1+/- mice. Methods and Results Two separate experimental groups of mice were subjected to myocardial infarction ( MI ) followed by the immediate intramyocardial injection of adenovirus carrying LacZ (Ad-LacZ) (1×109 pfu) or Ad-Peli1 (1×109 pfu). Heart tissues were collected for analyses. Compared with wild-type ( WTMI ) mice, analysis revealed decreased expressions of Peli1, phosphorylated (p-)Flk-1, p-Akt, p- eNOS , p- MK 2, p-IκBα, and NF -κB and decreased vessel densities in Flk-1+/- mice subjected to MI (Flk-1+/- MI ). Mice ( CD 1) treated with Ad-Peli1 after the induction of MI showed increased ß-catenin translocation to the nucleus, connexin 43 expression, and phosphorylation of Akt, eNOS , MK 2, and IκBα, that was followed by increased vessel densities compared with the Ad-LacZ-treated group. Echocardiography conducted 30 days after surgery showed decreased function in the Flk1+/- MI group compared with WTMI , which was restored by Ad-Peli1 gene therapy. In addition, therapy with Ad-Peli1 stimulated angiogenic and arteriogenic responses in both CD 1 and Flk-1+/- mice following MI . Ad-Peli1 treatment attenuated cardiac fibrosis in Flk-1+/- MI mice. Similar positive results were observed in CD 1 mice subjected to MI after Ad-Peli1 therapy. Conclusion Our results show for the first time that Peli1 plays a unique role in salvaging impaired collateral blood vessel formation, diminishes fibrosis, and improves myocardial function, thereby offering clinical potential for therapies in humans to mend a damaged heart following MI .


Assuntos
Terapia Genética/métodos , Infarto do Miocárdio/terapia , Proteínas Nucleares/farmacologia , Ubiquitina-Proteína Ligases/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Western Blotting , Células Cultivadas , Modelos Animais de Doenças , Regulação da Expressão Gênica , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos ICR , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Fosforilação , Transdução de Sinais , Ubiquitina-Proteína Ligases/biossíntese , Ubiquitina-Proteína Ligases/genética
18.
J Exp Biol ; 221(Pt 12)2018 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-29615525

RESUMO

Oxygen limitation plays a key role in many pathologies; yet, we still lack a fundamental understanding of the mechanisms responsible for variation in anoxia tolerance. Most vertebrate studies suggest that anoxia tolerance involves the ability to maintain cellular ATP despite the loss of aerobic metabolism. However, insects such as adult Drosophila melanogaster are able to survive long periods of anoxia (LT50: ∼8 h) in a hypo-energetic state characterized by low [ATP]. In this study, we tested for possible mechanisms that allow D. melanogaster adults to survive long periods of anoxia. Adults are paralyzed within 30 s, and after 2 h of anoxia, ATP was 3% of normal, extracellular potassium concentration ([K+]o) increased threefold, pH dropped 1 unit, yet survival was 100%. With 0.5-6 h of anoxia, adults maintained low but constant ATP levels while [K+]o and pHo continued to change. When returned to normoxia, adults restored [K+]o and activity. With longer durations of anoxia, ATP levels decreased and [K+]o rose further, and both correlated tightly with decreased survival. This response contrasts with the anoxia-sensitive larval stage (LT50: ∼1 h). During anoxia, larvae attempted escape for up to 30 min and after 2 h of anoxia, ATP was <1% of resting, [K+]o increased by 50%, hemolymph pH fell by 1 unit, and survival was zero. The superior anoxia tolerance of adult D. melanogaster appears to be due to the capacity to maintain a paralytic hypometabolic state with low but non-zero ATP levels, and to be able to tolerate extreme extracellular ionic variability.


Assuntos
Trifosfato de Adenosina/metabolismo , Drosophila melanogaster/fisiologia , Metabolismo Energético , Potássio/metabolismo , Anaerobiose , Animais , Drosophila melanogaster/crescimento & desenvolvimento , Feminino , Concentração de Íons de Hidrogênio , Larva/crescimento & desenvolvimento , Larva/fisiologia , Longevidade , Masculino
19.
J Surg Res ; 220: 68-78, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29180214

RESUMO

BACKGROUND: Sepsis is a leading cause of mortality among patients in intensive care units across the USA. Thioredoxin-1 (Trx-1) is an essential 12 kDa cytosolic protein that, apart from maintaining the cellular redox state, possesses multifunctional properties. In this study, we explored the possibility of controlling adverse myocardial depression by overexpression of Trx-1 in a mouse model of severe sepsis. METHODS: Adult C57BL/6J and Trx-1Tg/+ mice were divided into wild-type sham (WTS), wild-type cecal ligation and puncture (WTCLP), Trx-1Tg/+sham (Trx-1Tg/+S), and Trx-1Tg/+CLP groups. Cardiac function was evaluated before surgery, 6 and 24 hours after CLP surgery. Immunohistochemical and Western blot analysis were performed after 24 hours in heart tissue sections. RESULTS: Echocardiography analysis showed preserved cardiac function in the Trx-1Tg/+ CLP group compared with the WTCLP group. Similarly, Western blot analysis revealed increased expression of Trx-1, heme oxygenase-1 (HO-1), survivin (an inhibitor of apoptosis [IAP] protein family), and decreased expression of thioredoxin-interacting protein (TXNIP), caspase-3, and 3- nitrotyrosine in the Trx-1Tg/+CLP group compared with the WTCLP group. Immunohistochemical analysis showed reduced 4-hydroxynonenal, apoptosis, and vascular leakage in the cardiac tissue of Trx-1Tg/+CLP mice compared with mice in the WTCLP group. CONCLUSIONS: Our results indicate that overexpression of Trx-1 attenuates cardiac dysfunction during CLP. The mechanism of action may involve reduction of oxidative stress, apoptosis, and vascular permeability through activation of Trx-1/HO-1 and anti-apoptotic protein survivin.


Assuntos
Permeabilidade Capilar , Cardiomiopatias/metabolismo , Proteínas Inibidoras de Apoptose/metabolismo , Proteínas Repressoras/metabolismo , Sepse/complicações , Tiorredoxinas/metabolismo , Aldeídos/metabolismo , Animais , Apoptose , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/etiologia , Proteínas de Transporte/metabolismo , Caspase 3/metabolismo , Modelos Animais de Doenças , Ecocardiografia , Feminino , Coração/diagnóstico por imagem , Heme Oxigenase-1/metabolismo , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Miocárdio/patologia , Estresse Oxidativo , Survivina , Tiorredoxinas/genética , Tirosina/análogos & derivados , Tirosina/metabolismo
20.
Cureus ; 9(5): e1254, 2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28649477

RESUMO

Computed tomography angiography (CTA) has become an effective tool in the evaluation of patients with subarachnoid hemorrhage (SAH), but it still has limitations. Up to 15% of non-traumatic SAH cases are negative on CTA. The benefits of catheter angiography in the evaluation of certain cases of CTA-negative SAH have been previously demonstrated. Here, we present the case of a 48-year-old female who presented with headache and right-sided hemiparesis, who later became apneic and required intubation. A computed tomography (CT) scan of the head demonstrated a diffuse SAH. A CTA of the head and neck showed no vascular abnormality. Catheter angiography diagnosed a conical-shaped aneurysm at the left A1-A2 junction of the anterior communicating artery complex measuring 3.5 mm by 1 mm. The aneurysm was successfully treated with a craniotomy and microvascular clipping using a 4.7 mm curved Yasargil miniclip (Aesculap, Tuttlingen, Germany). This case illustrates the importance and benefit of catheter angiography in CTA-negative cases of SAH.

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