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1.
BMC Biol ; 22(1): 27, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317219

RESUMO

BACKGROUND: Staphylococcus aureus (SA) and Pseudomonas aeruginosa (PA) cause a wide variety of bacterial infections and coinfections, showing a complex interaction that involves the production of different metabolites and metabolic changes. Temperature is a key factor for bacterial survival and virulence and within the host, bacteria could be exposed to an increment in temperature during fever development. We analyzed the previously unexplored effect of fever-like temperatures (39 °C) on S. aureus USA300 and P. aeruginosa PAO1 microaerobic mono- and co-cultures compared with 37 °C, by using RNAseq and physiological assays including in vivo experiments. RESULTS: In general terms both temperature and co-culturing had a strong impact on both PA and SA with the exception of the temperature response of monocultured PA. We studied metabolic and virulence changes in both species. Altered metabolic features at 39 °C included arginine biosynthesis and the periplasmic glucose oxidation in S. aureus and P. aeruginosa monocultures respectively. When PA co-cultures were exposed at 39 °C, they upregulated ethanol oxidation-related genes along with an increment in organic acid accumulation. Regarding virulence factors, monocultured SA showed an increase in the mRNA expression of the agr operon and hld, pmsα, and pmsß genes at 39 °C. Supported by mRNA data, we performed physiological experiments and detected and increment in hemolysis, staphyloxantin production, and a decrease in biofilm formation at 39 °C. On the side of PA monocultures, we observed an increase in extracellular lipase and protease and biofilm formation at 39 °C along with a decrease in the motility in correlation with changes observed at mRNA abundance. Additionally, we assessed host-pathogen interaction both in vitro and in vivo. S. aureus monocultured at 39οC showed a decrease in cellular invasion and an increase in IL-8-but not in IL-6-production by A549 cell line. PA also decreased its cellular invasion when monocultured at 39 °C and did not induce any change in IL-8 or IL-6 production. PA strongly increased cellular invasion when co-cultured at 37 and 39 °C. Finally, we observed increased lethality in mice intranasally inoculated with S. aureus monocultures pre-incubated at 39 °C and even higher levels when inoculated with co-cultures. The bacterial burden for P. aeruginosa was higher in liver when the mice were infected with co-cultures previously incubated at 39 °C comparing with 37 °C. CONCLUSIONS: Our results highlight a relevant change in the virulence of bacterial opportunistic pathogens exposed to fever-like temperatures in presence of competitors, opening new questions related to bacteria-bacteria and host-pathogen interactions and coevolution.


Assuntos
Infecções por Pseudomonas , Infecções Estafilocócicas , Camundongos , Animais , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Virulência/fisiologia , Pseudomonas aeruginosa , Temperatura , Interleucina-6/metabolismo , Interleucina-6/farmacologia , Interleucina-8/metabolismo , Interleucina-8/farmacologia , Infecções por Pseudomonas/microbiologia , RNA Mensageiro/metabolismo , Biofilmes , Infecções Estafilocócicas/microbiologia
2.
BMC Pregnancy Childbirth ; 23(1): 457, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340350

RESUMO

BACKGROUND: Access to health services during pregnancy, childbirth and the period after birth provides a substantial opportunity to limit cases of maternal mortality. In sub-Saharan Africa, the proportions of women who utilize health services remain below 70%. This study examined the factors associated with partial and adequate maternal health services utilization in Nigeria. METHODS: This paper used data from 2018 Nigeria Demographic and Health Survey (DHS) comprising 21,792 women aged 15-49 years who had given births within five years of the survey. The study focused on antenatal care attendance, place of birth and postnatal care using a combined model. Multinomial logistic regression was applied in the analysis. RESULTS: About 74% of the women attended antenatal care, 41% gave birth in health facilities and 21% attended postnatal care. While 68% of the women partially utilized health services, 11% adequately utilized the services. The odds of partially and adequately utilizing health services increased for ever married women, women with secondary or higher education, from richest households, living in urban area, having no problem either getting permission to visit health facility or reaching health facility. CONCLUSIONS: This study has revealed the factors associated with partial and adequate utilization of maternal health services in Nigeria. Such factors include education, household wealth, marital status, employment status, residence, region, media exposure, getting permission to use health service, unwillingness to visit health facility without being accompanied and distance to health facility. Efforts aimed at improving maternal health services utilization should place emphasis on these factors.


Assuntos
Serviços de Saúde Materna , Feminino , Gravidez , Humanos , Estudos Transversais , Nigéria , Aceitação pelo Paciente de Cuidados de Saúde , Cuidado Pré-Natal
3.
Chin J Physiol ; 62(3): 108-116, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31249264

RESUMO

Reports on the coexistence of diabetes mellitus and osteoarthritis in human subjects dated back to the 1960s. However, there is no account in literature on the co-manifestation of these disease conditions in experimental animals. In our previous study, we reported for the first time, the effects of pharmacological agents on glucoregulatory indices, lipid profile, and inflammatory markers in experimental diabetic-knee osteoarthritic rat. However, in the present study, the effects of salmon calcitonin (Sct), and/or omega-3 fatty acids (N-3) were further investigated on other biomarkers. Forty-nine rats of seven animals per group were used for this study. Diabetes was induced by the administration of streptozotocin (65 mg/kg) and nicotinamide (110 mg/kg). Thereafter, knee osteoarthritis was induced by the intra-articular injection of 4 mg of sodium monoiodoacetate in 40 µl of saline. Nine days after the inductions, treatments started, and they lasted for 4 weeks. N-3 was administered at 200 mg/kg/day, while Sct was administered at 2.5 and 5.0 IU/kg/day. The results of the study indicated that the induced diabetes-knee osteoarthritis caused significant alterations in all the observed biomarkers. Sct showed a dose-specific effect and an additive action with N-3 in reducing malondialdehyde and lactate dehydrogenase, and in elevating total bilirubin and total antioxidant capacity. However, it largely demonstrated a nondose-specific effect and nonadditive action with N-3 on superoxide dismutase, catalase, glutathione peroxidase, total alkaline phosphatase, c-telopeptide of type-I collagen, collagen type-2 alpha 1, and hematological indices. In conclusion, the combined administration of Sct and N-3 proffer better therapeutic effects than the single therapy; therefore, they could be used in the management of diabetic-osteoarthritic condition.


Assuntos
Cartilagem , Animais , Antioxidantes , Biomarcadores , Calcitonina , Ácidos Graxos Ômega-3 , Ratos
4.
Exp Mol Pathol ; 103(2): 113-120, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28757388

RESUMO

Clinical evidences on the coexistence of diabetes mellitus (DM) and osteoarthritis (OA) dated back to the 1960s. Therefore, the study investigated the effects of induced DM and/or knee osteoarthritis (KOA) on some biochemical and haematological parameters in adult male Wistar rats. Twenty rats were used for this study. They were randomly divided into 4 groups (N=5 rats) which included: Normal control; Osteoarthritic (OA) control; Diabetic control; and, Diabetic+Osteoarthritic (D+OA) control. DM was induced in overnight fasted rats by the administration of streptozotocin (65mg/kg b.w., i.p.) 15min after the administration of nicotinamide (110mg/kg, b.w., i.p.). However, KOA was induced by the intra-articular injection of 4mg of sodium monoiodoacetate in 40µl of normal saline. In the D+OA group, KOA was induced about 12h after the induction of DM. The rats were left untreated for four weeks. Afterwards, the experiment was terminated. The results showed that both DM and OA featured hypercortisolism and dyslipidaemia. The additive effects of both conditions were observed on the lipid profile and some haematological indices in the D+OA group. Unlike DM, OA had mild adverse effects on the haematological profile. Nevertheless, it significantly contributed to hyperglycaemia in the D+OA group, even though it had no significant effect on the insulin resistance. However, the hypocalcaemic and glycogenolytic effects of DM were negated by OA. In conclusion, the coexistence of DM and OA presents a greater challenge on the biochemical and haematological profiles than the individual disease. But, this prediction could sometimes be annulled by the intervention of endogenous homeostatic mechanisms.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Testes Hematológicos , Hiperglicemia/fisiopatologia , Resistência à Insulina , Lipídeos/análise , Osteoartrite do Joelho/fisiopatologia , Animais , Glicemia/metabolismo , Hidrocortisona/sangue , Glicogênio Hepático/sangue , Masculino , Ratos , Ratos Wistar
5.
Toxicol Ind Health ; 32(12): 1935-1941, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26381688

RESUMO

Exposure to arsenic and mercury is known to cause respiratory problems in both humans and animals. In this study, we elicit and compare maximum contraction caused by As(III) and Hg(II) when the pollutants are fully equilibrated with contractile machinery in resting mode. Hypercontraction of 27% and 69% was obtained following exposure of tracheal rings to 25 µM As(III) and 6 nM Hg(II) for 40 min, respectively. Co-incubation of tracheal rings with pollutants and verapamil, sodium nitroprusside or apocynin indicates that major contributors to As(III) and Hg(II) caused hypercontraction are reactive oxygen species (ROS) elevation and nitric oxide (NO) depletion. Changes in calcium influx have minor contribution in As(III) and Hg(II) caused increased contraction of tracheal tissues. Eugenol and carvone caused relaxation of 38% and 45% in pollutant unexposed rings, 56% and 49% in As(III)-exposed tracheal rings, and 54% and 47% in Hg(II)-exposed tracheal rings. Pathway delineation studies indicate that the major effect of eugenol originates from quenching of ROS whereas that of carvone originates from the blockage of extracellular calcium influx. Both molecules also show a minor stimulatory effect on NO generation. In line with their suggested mode of relaxation, eugenol is found to better ameliorate both As(III)- and Hg(II)-caused hypercontraction. Carvone, though a better relaxant than eugenol, comes out as poor ameliorator of both As(III)- and Hg(II)-caused hypercontraction, as the pathway on which it acts is not elevated following exposure to these pollutants.


Assuntos
Arsênio/toxicidade , Eugenol/farmacologia , Mercúrio/toxicidade , Monoterpenos/farmacologia , Traqueia/efeitos dos fármacos , Acetofenonas/farmacologia , Animais , Monoterpenos Cicloexânicos , Técnicas In Vitro , Masculino , Óxido Nítrico/metabolismo , Nitroprussiato/farmacologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Traqueia/metabolismo , Verapamil/farmacologia
6.
ACS Biomater Sci Eng ; 10(3): 1819-1829, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38366973

RESUMO

Allergen immunotherapies are often successful at desensitizing allergic patients but can require life-long dosing and suffer from frequent adverse events including instances of systemic anaphylaxis, leading to poor patient compliance and high cost. Allergen vaccines, in turn, can generate more durable immunological allergen desensitization with far fewer doses. However, like immunotherapies, allergen vaccines are often highly reactogenic in allergic patients, hampering their use in therapeutic settings. In this work, we utilize a peptide-based self-assembling nanofiber platform to design allergen vaccines against allergen B-cell epitopes that do not elicit systemic anaphylaxis when administered subcutaneously to allergic mice. We show that, in contrast to protein vaccines, nanofiber vaccines prevent leakage of allergen material into the vascular compartment, a feature that likely underpins their reduced systemic reactogenicity. Further, we show that our allergen vaccine platform elicits therapeutic IgG antibody responses capable of desensitizing allergic mice to allergen-induced Type I hypersensitivity reactions. Finally, we have demonstrated a proof-of-concept for the therapeutic potential of nanofiber-based peanut allergen vaccines directed against peanut allergen-derived epitopes.


Assuntos
Anafilaxia , Vacinas , Humanos , Animais , Camundongos , Alérgenos , Dessensibilização Imunológica , Imunoglobulina G
7.
Braz J Biol ; 84: e284907, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39383412

RESUMO

Utilizing coastal land for agriculture presents challenges such as low water content, high soil salinity, and low organic compound content. To support plant growth under these conditions, biofertilizers composed of plant growth promoting Rhizobacteria (PGPR), especially those inhabiting coastal areas, are needed. The Parangkusumo sand dunes on the southern coast of Java, Indonesia, is a unique coastal ecosystem characterized by arid conditions, high temperatures, and high soil salinity. To date, no studies have reported the isolation of PGPR from this ecosystem. This study is the first to isolate and identify PGPR associated with Spinifex littoreus, a dominant plant species in the Parangkusumo sand dunes, which are adapted to the harsh condition of Parangkusumo sand dunes. Ten rhizobacterial isolates were obtained, with five identified as members of the Bacillaceae family. All isolates demonstrated phosphate solubilization activity, while seven exhibited cellulolytic activity. One isolate, Priestia aryabhattai strain 2, notably showed phosphate solubilization and nitrogen fixation activities. The findings of this PGPR activity screening offer valuable insights for developing biofertilizers tailored for coastal agricultural applications.


Assuntos
Microbiologia do Solo , Indonésia , Areia/microbiologia , Fixação de Nitrogênio
8.
Heliyon ; 10(8): e29518, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38665563

RESUMO

The need to explore the abundance of natural products cannot be overemphasized particularly in the management of various disease conditions. In traditional medical practice, Vernonia amygdalina has been widely adopted in the management of various inflammatory disorders. The objective of this investigation was to isolate the bioactive principles from the stem-bark and root of V. amygdalina and assess the anti-inflammatory (in vitro) activity of both the crude extracts and the isolated compounds. Following extraction with the methanol, the extract was subjected to gravity column chromatography and the resultant fractions was further purified to obtained pure compounds. The structural elucidation of the compounds were based on data obtained from 1H to 13C nuclear magnetic resonance (NMR) spectroscopies as well as fourier transform infrared (FT-IR). Using diclofenac as a control drug, the albumin denaturation assay was used to determine the in vitro anti-inflammatory activity of the extracts and isolates. Three distinct compounds characterized are vernoamyoside D, luteolin-7-α-o-glucuronide, and vernotolaside, a new glycoside. When compared to diclofenac, which has an IC50 of 167.8 µg/mL, luteolin-7-α-o-glucuronide, vernoamyoside D, and vernotolaside all showed significant inhibitions with respective IC50 values 549.8, 379.5, and 201.7 µg/mL. Vernotolaside is reported for the first time from the root. The assertion that the plant is used in traditional medicine for the management of inflammatory disorder is somewhat validated by the confirmation of the existence of the compounds with the biochemical actions. Further validation of the isolated compounds would be required in animal studies.

9.
Afr Health Sci ; 23(1): 492-503, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37545939

RESUMO

Background: The most common intracranial neoplasm worldwide is meningioma, followed by gliomas, and then pituitary adenomas. There are geographical differences in the pattern of occurrence of intracranial neoplasms.The purpose of this study is to establish the pattern of occurrence of different histological types of intracranial neoplasms with their age and sex distributions in our environment - Lagos, Nigeria.The histological patterns, age, and gender distributions of all the intracranial neoplasms diagnosed within the study period at the Department of Anatomic and Molecular Pathology, LUTH, Lagos, Nigeria were noted and analysed with SPSS version 23. Result: There were 296 patients (165 females, 131 males; mean age of 37.0 years) diagnosed with an intracranial neoplasm within the study period. The most frequently diagnosed intracranial neoplasm was meningioma (105 cases; 35%, median age of 42 years, male to female ratio of 1:2.2), followed by pituitary adenoma (78 cases; 26%, median age of 47 years, male to female ratio of 1.3:1), and then gliomas (71 cases; 24%, median age of 28, male to female ratio of 1:1.39). Conclusion: The result of the study shows pituitary adenoma to be more common than gliomas, unlike what is seen in Caucasians where the reverse is the case.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Meníngeas , Meningioma , Neoplasias Hipofisárias , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Meningioma/epidemiologia , Neoplasias Hipofisárias/epidemiologia , Nigéria/epidemiologia , Universidades , Hospitais de Ensino , Neoplasias Encefálicas/epidemiologia , Glioma/epidemiologia
10.
Front Endocrinol (Lausanne) ; 14: 1329564, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38260147

RESUMO

Studies have implicated oxidative stress-sensitive signaling in the pathogenesis of stress-induced male infertility. However, apart from oxidative stress, gonadotropin inhibitory hormone (GnIH) plays a major role. The present study provides a detailed review of the role of GnIH in stress-induced male infertility. Available evidence-based data revealed that GnIH enhances the release of corticosteroids by activating the hypothalamic-pituitary-adrenal axis. GnIH also mediates the inhibition of the conversion of thyroxine (T4) to triiodothyronine (T3) by suppressing the hypothalamic-pituitary-thyroidal axis. In addition, GnIH inhibits gonadotropin-releasing hormone (GnRH), thus suppressing the hypothalamic-pituitary-testicular axis, and by extension testosterone biosynthesis. More so, GnIH inhibits kisspeptin release. These events distort testicular histoarchitecture, impair testicular and adrenal steroidogenesis, lower spermatogenesis, and deteriorate sperm quality and function. In conclusion, GnIH, via multiple mechanisms, plays a key role in stress-induced male infertility. Suppression of GnIH under stressful conditions may thus be a beneficial prophylactic and/or therapeutic strategy.


Assuntos
Sistema Hipotálamo-Hipofisário , Infertilidade Masculina , Masculino , Humanos , Sistema Hipófise-Suprarrenal , Sêmen , Gonadotropinas , Infertilidade Masculina/etiologia , Fertilidade
11.
bioRxiv ; 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-36993402

RESUMO

Background: Staphylococcus aureus and Pseudomonas aeruginosa cause a wide variety of bacterial infections and coinfections, showing a complex interaction that involves the production of different metabolites and metabolic changes. Temperature is a key factor for bacterial survival and virulence and within the host, bacteria could be exposed to an increment in temperature during fever development. We analyzed the previously unexplored effect of fever-like temperatures (39°C) on S. aureus USA300 and P. aeruginosa PAO1 microaerobic mono- and co-cultures compared with 37°C, by using RNAseq and physiological assays including in-vivo experiments. Results: In general terms both temperature and co-culturing had a strong impact on both PA and SA with the exception of the temperature response of monocultured PA. We studied metabolic and virulence changes on both species. Altered metabolic features at 39°C included arginine biosynthesis and the periplasmic glucose oxidation in S. aureus and P. aeruginosa monocultures respectively. When PA co-cultures were exposed at 39°C they upregulated ethanol oxidation related genes along with an increment in organic acid accumulation. Regarding virulence factors, monocultured SA showed an increase in the mRNA expression of the agr operon and hld, pmsα and pmsß genes at 39°C. Supported by mRNA data, we performed physiological experiments and detected and increment in hemolysis, staphylxantin production and a decrease in biofilm formation at 39°C. On the side of PA monocultures, we observed increase in extracellular lipase and protease and biofilm formation at 39°C along with a decrease in motility in correlation with changes observed at mRNA abundance. Additionally, we assessed host-pathogen interaction both in-vitro and in-vivo . S. aureus monocultured at 39°C showed a decrease in cellular invasion and an increase in IL-8 -but not in IL-6- production by A549 cell line. PA also decreased its cellular invasion when monocultured at 39°C and did not induce any change in IL-8 or IL-6 production. PA strongly increased cellular invasion when co-cultured at 37°C and 39°C. Finally, we observed increased lethality in mice intranasally inoculated with S. aureus monocultures pre-incubated at 39°C and even higher levels when inoculated with co-cultures. The bacterial burden for P. aeruginosa was higher in liver when the mice were infected with co-cultures previously incubated at 39°C comparing with 37°C. Conclusion: Our results highlight a relevant change in the virulence of bacterial opportunistic pathogens exposed to fever-like temperatures in presence of competitors, opening new questions related to bacteria-bacteria and host-pathogen interactions and coevolution.

12.
J Geriatr Cardiol ; 20(1): 11-22, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36875169

RESUMO

OBJECTIVES: Syncope at age 65+ is associated with increased mortality, irrespective of cause. Syncope rules were designed to aid in risk-stratification but were only validated in the general adult population. Our objective was to determine if they can be applied to a geriatric population in predicting short-term adverse outcomes. METHODS: In this single-center retrospective study, we evaluated 350 patients aged 65+ presenting with syncope. Exclusion criteria included confirmed non-syncope, active medical condition, drug or alcohol-related syncope. Patients were stratified into high or low risk based on Canadian Syncope Risk Score (CSRS), Evaluation of Guidelines in Syncope Study (EGSYS), San Francisco Syncope Rule (SFSR), and Risk Stratification of Syncope in the Emergency Department (ROSE). Composite adverse outcomes at 48-hour and 30-day included all-cause mortality, major adverse cardiac and cerebrovascular events (MACCE), return emergency department visit, hospitalization, or medical intervention. We assessed each score's ability to predict the outcomes using logistic-regression and compared performances using receiver-operator curves. Multivariate analyses were performed to study the associations between recorded parameters and outcomes. RESULTS: CSRS outperformed with AUC of 0.732 (95% CI: 0.653-0.812) and 0.749 (95% CI: 0.688-0.809) for 48-h and 30-day outcomes, respectively. Sensitivities for CSRS, EGSYS, SFSR, and ROSE for 48-hour outcomes were 48%, 65%, 42% and 19%; and for 30-day outcomes were 72%, 65%, 30% and 55%, respectively. Atrial fibrillation/flutter on EKG, congestive heart failure, antiarrhythmics, systolic blood-pressure < 90 at triage, and associated chest pain highly correlated with 48-h outcomes. An EKG abnormality, heart disease history, severe pulmonary hypertension, BNP > 300, vasovagal predisposition, and antidepressants highly correlated with 30-day outcomes. CONCLUSIONS: Performance and accuracy of four prominent syncope rules were suboptimal in identifying high-risk geriatric patients with short-term adverse outcomes. We identified some significant clinical and laboratory information that may play a role in predicting short-term adverse events in a geriatric cohort.

13.
Microb Pathog ; 52(5): 251-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22227461

RESUMO

Effect of cinnamaldehyde (CD), 4-hydroxy-3-methoxy cinnamaldehyde (HMCD) and 3,5-dimethoxy-4-hydroxy cinnamaldehyde (HDMCD) on growth and virulence factors of standard (Candida albicans 90028) and 26 oral isolates of C. albicans has been investigated. Growth was significantly inhibited by all three compounds in both solid and liquid medium, no systematic difference was observed between various isolates. MIC90 ranged from 125 to 450 µg/ml for CD, 100-250 µg/ml for HMCD and 62.5-125 µg/ml for HDMCD. All oral isolates were found to be proteinase and phospholipase secretors, both proteinase and phospholipase secretion was significantly inhibited by all the three tested molecules. No systematic difference in secretion or its inhibition was observed between standard and oral isolates as also between various isolates. Average drop in proteinase and phospholipase secretion caused by ½ MIC of CD was 33% and 28%, HMCD; 46% and 44%, HDMCD; 59% and 54%. The standard strain and all the 26 oral isolates displayed morphogenesis under triggering experimental conditions; no difference was seen between standard and various isolates. In the absence of test compounds hyphae development at 300 min was 83% for standard strain whereas average hyphae development for oral isolates was 85%. Average hyphal transition was suppressed by all tested compounds. At ½ MIC concentration at 300 min average hyphal transition of standard and oral isolates was CD; 49% and 57%, HMCD; 45% and 38%, HDMCD; 5% and 5%. Average haemolytic activity of the three tested compounds varied from 10 to 15% at their highest MIC compared to 20% shown by fluconazole at typical MIC of 30 µg/ml.


Assuntos
Acroleína/análogos & derivados , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Candidíase Bucal/microbiologia , Proteínas Fúngicas/metabolismo , Acroleína/farmacologia , Candida albicans/enzimologia , Candida albicans/isolamento & purificação , Humanos , Hifas/efeitos dos fármacos , Hifas/enzimologia , Hifas/genética , Hifas/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Peptídeo Hidrolases/metabolismo , Fosfolipases/metabolismo , Transporte Proteico
14.
J Basic Microbiol ; 52(5): 504-12, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22143929

RESUMO

This work evaluates the antifungal activity of two essential oil components against 28 clinical isolates (17 sensitive, 11 resistant) and 3 standard laboratory strains of Candida. Growth of the organisms was significantly effected in both solid and liquid media at different test compound concentrations. The minimum inhibitory concentrations (MICs) of Isoeugenol (compound 1) against 31 strains of Candida ranged 100-250 µg/ml and those of o -methoxy cinnamaldehyde (compound 2) ranged 200-500 µg/ml, respectively. Insight studies to mechanism suggested that these compounds exert antifungal activity by targeting H(+)-ATPase located in the membranes of pathogenic Candida species. At their respective MIC(90) average inhibition of H(+)-efflux for standard, clinical and resistant isolates caused by compound 1 and compound 2 was 70%, 74%, 82% and 42%, 42% and 43%. Respective inhibition of H(+)-efflux by fluconazole (5 µg/ml) was 94%, 92% and 10%. Inhibition of H(+)-ATPase leads to intracellular acidification and cell death. SEM analysis of Candida cells showed cell membrane breakage and alterations in morphology. Haemolytic activity on human erythrocytes was studied to exclude the possibility of further associated cytotoxicity.


Assuntos
Antifúngicos/metabolismo , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/enzimologia , Óleos Voláteis/metabolismo , Óleos Voláteis/farmacologia , ATPases Translocadoras de Prótons/metabolismo , Acroleína/análogos & derivados , Acroleína/metabolismo , Acroleína/farmacologia , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Candidíase/microbiologia , Eritrócitos/efeitos dos fármacos , Eugenol/análogos & derivados , Eugenol/metabolismo , Eugenol/farmacologia , Humanos , Testes de Sensibilidade Microbiana
15.
Biol Trace Elem Res ; 200(3): 1212-1219, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33939131

RESUMO

Airway smooth muscle contraction is one of the primary factors involved in the initiation and progression of asthma which in turn is regulated by increased cytosolic Ca2+ concentration from intracellular stores and through transmembrane ion channels. Calcium-independent factors such as reactive oxygen species (ROS) generation, nitric oxide (NO) depletion and cyclooxygenase (COX) pathways also contribute to tracheal smooth muscle contraction. Studies on copper toxicity suggest significance of this essential micronutrient overdose in acute respiratory disorders, allergic asthma and ciliary motion in tracheal explants. However, the mechanism of copper caused hypercontraction upon direct exposure to tracheal smooth muscle is largely unknown. In this study we investigate the effect of copper exposure on isolated tracheal rings and relative contributions of various factors in acetylcholine-induced contractions. Results obtained suggest that rise in intracellular calcium concentration via voltage-operated Ca2+ channel (VOCC), store-operated Ca2+ channel (SOCC), stretch-activated channels (SAC) and TRP channel (transient receptor potential channel) activation is the major factor in copper-mediated hypercontraction. ROS generation or COX-dependent pathways do not appear to significantly contribute to Cu2+ caused hypercontraction.


Assuntos
Contração Muscular , Músculo Liso , Acetilcolina , Animais , Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Ratos
16.
Sci Adv ; 8(47): eabq4120, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36417519

RESUMO

Urinary tract infections (UTIs) are a major public health problem affecting millions of individuals each year. Recurrent UTIs are managed by long-term antibiotic use, making the alarming rise of antibiotic resistance a substantial threat to future UTI treatment. Extended antibiotic regimens may also have adverse effects on the microbiome. Here, we report the use of a supramolecular vaccine to provide long-term protection against uropathogenic Escherichia coli, which cause 80% of uncomplicated UTIs. We designed mucus-penetrating peptide-polymer nanofibers to enable sublingual (under the tongue) vaccine delivery and elicit antibody responses systemically and in the urogenital tract. In a mouse model of UTI, we demonstrate equivalent efficacy to high-dose oral antibiotics but with significantly less perturbation of the gut microbiome. We also formulate our vaccine as a rapid-dissolving sublingual tablet that raises response in mice and rabbits. Our approach represents a promising alternative to antibiotics for the treatment and prevention of UTIs.


Assuntos
Infecções por Escherichia coli , Nanofibras , Infecções Urinárias , Vacinas , Camundongos , Coelhos , Animais , Infecções por Escherichia coli/prevenção & controle , Infecções Urinárias/prevenção & controle , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
17.
Microb Pathog ; 51(4): 277-84, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21669279

RESUMO

Attention has been drawn to evaluate the antifungal activity of p-anisaldehyde (1), o-anisaldehyde (2) and m-anisaldehyde (3). To put forward this approach, antifungal activity has been assessed in thirty six fluconazole-sensitive and eleven fluconazole-resistant Candida isolates. Growth and sensitivity of the organisms were significantly effected by test compounds at different concentrations. The rapid irreversible action of compound-1, compound-2 and compound-3 on fungal cells suggested a membrane-located target for their action. We investigated their effect on H(+) ATPase mediated H(+)-pumping by various Candida species. All the compounds inhibit H(+)- ATPase activity at their respective MIC(90) values. Inhibition of H(+) ATPase leads to intracellular acidification and cell death. Scanning electron microscopy analysis revealed deep wrinkles, deformity and flowed content. Furthermore, it was also observed that position of methoxy group attached to the benzene ring decides antifungal activity of the compound. The present study indicates that compound-1, compound-2 and compound-3 have significant antifungal activity against Candida, including azole-resistant strains, advocating further investigation for clinical applications in the treatment of fungal infections.


Assuntos
Antifúngicos/farmacologia , Benzaldeídos/farmacologia , Candida/efeitos dos fármacos , Candida/enzimologia , ATPases Translocadoras de Prótons/antagonistas & inibidores , Antifúngicos/química , Benzaldeídos/química , Candida/citologia , Candida/crescimento & desenvolvimento , Fluconazol/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Relação Estrutura-Atividade
18.
Med Mycol ; 49(4): 444-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21128712

RESUMO

The effect of diallyl sulphide (DAS) and diallyl disulphide (DADS) on secretion of hydrolytic enzymes and dimorphism has been investigated in two strains of Candida albicans. Minimum inhibitory concentration (MIC) of DADS and DAS was determined to be 500 µg/ml and 40 µg/ml, respectively for a clinical isolate (accession #3043) and 450 µg/ml and 50 µg/ml, respectively, for a reference strain (ATCC 90028). At one-half of the minimum inhibitory concentration (MIC), DAS and DADS inhibited proteinase secretion by 24% and 35%, respectively, in the clinical strain, and 28% and 44%, respectively, in the reference strain. Inhibition of phospholipase secretion at one-half MIC of DAS and DADS was 27% and 60%, respectively, in the clinical strain and 31% and 64%, respectively, for the reference strain. Hyphal induction at 300 min in the reference strain was 15% (at one-half MIC of DAS) and 5% (at one-half the MIC of DADS) as compared to control (90% hyphal formation). Hyphal induction in the clinical strain was 16% (one-half the MIC of DAS) and 8% (one-half the MIC of DADS) compared to 95% in the control. To conclude, both DAS and DADS significantly inhibit proteinase, phospholipase secretion and dimorphism in C. albicans. These compounds can therefore be explored for their therapeutic potential against C. albicans.


Assuntos
Compostos Alílicos/farmacologia , Candida albicans/efeitos dos fármacos , Dissulfetos/farmacologia , Alho/química , Hifas/efeitos dos fármacos , Sulfetos/farmacologia , Candida albicans/enzimologia , Candida albicans/crescimento & desenvolvimento , Hifas/enzimologia , Hifas/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Fosfolipases/metabolismo
19.
J Gastroenterol Hepatol ; 26(1): 135-44, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21175807

RESUMO

BACKGROUND AND AIM: Persistent infection with hepatitis B virus (HBV) is a major etiological risk factor for hepatocellular carcinoma (HCC). The host cellular components involved in the progression of the carcinoma are still unclear. In the present study we aimed to evaluate Ras mediated signaling in hepatocellular carcinoma with persistent HBV infection. METHODS: To gain insight into the role of Ras mediated signaling in HBV mediated carcinogenesis we evaluated Ras functionality by mutation analysis, reverse transcription-polymerase chain reaction, immunohistochemistry (IHC), Ras-guanosine triphosphate bound functionality assay and Ras-mediated downstream signaling in a cohort of primary HCC tissues positive for HBV-DNA. RESULTS: Mutation in codon 12 of K-ras appeared to be an uncommon event in the pathogenesis of HCC. We found unusually low levels of Ras expression in HCC compared with those with normal liver and chronic liver disease (cirrhosis and chronic hepatitis). Considerable heterogeneity was found with respect to Ras-mediated signaling events (pRaf, pMAPK and pAKT). The hepatoma cell line (Hep3B) with integrated HBV showed upregulation in expression and activation of Ras and its downstream signaling in comparison to HBV a negative cell line (HepG2). The contrasting result between the cell lines and primary tumors is worthy of note. CONCLUSIONS: The unusual finding on downregulation of Ras expression in primary HCC tumors in the present study together with tumor heterogeneity with respect to Ras-mediated signaling events prompts a new role of the wild type K-Ras as a possible growth suppressor and a stochastic model for progression of hepatic cancer.


Assuntos
Carcinoma Hepatocelular/metabolismo , Hepatite B/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais , Proteínas ras/metabolismo , Adulto , Idoso , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Códon , Regulação para Baixo , Feminino , Células Hep G2 , Hepatite B/complicações , Hepatite B/genética , Humanos , Imuno-Histoquímica , Índia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Fosforilação , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas ras/genética
20.
Biometals ; 24(5): 923-33, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21476019

RESUMO

Antifungal effectivity and utility of cinnamaldehyde is limited because of its high MIC and skin sensitivity. In this study, α-methyl trans cinnamaldehyde, a less irritating derivative, have been self coupled and complexed with Co(II) and Ni(II) to generate N, N'-Bis (α-methyl trans cinnamadehyde) ethylenediimine [C(22)H(24)N(2)], [Co(C(44)H(48)N(4))Cl(2)] and [Ni(C(44)H(48)N(4))Cl(2)]. Ligand and complexes were characterized on the basis of FTIR, ESI-MS, IR and (1)HNMR techniques. Synthesized ligand [L] and complexes were investigated for their MICs, inhibition of ergosterol biosynthesis and H(+) extrusion against three strains of Candida: C. albicans 44829, C. tropicalis 750 and C. krusei 6258. Average of three species MIC of methyl cinnamaldehyde is 317 µg/ml (2168 µM). Compared to methyl cinnamaldehyde ligand [L], Co(II) and Ni(II) complex are found to be 4.48, 17.78 and 21.46 times more effective in liquid medium and 2.73, 8.93 and 10.38 times more effective in solid medium. At their respective MIC(90) average inhibition of ergosterol biosynthesis caused by methyl cinnamaldehyde, ligand [L], Co(II) and Ni(II) complex, respectively was 80, 78, 90 and 93%. H(+) extrusion was also significantly inhibited but did not co-relate well with MIC(90). Results indicate ergosterol biosynthesis as site of action of α-methyl cinnamaldehyde, synthesized ligand and complexes. α-methyl cinnamaldehyde and ligand did not show any toxicity against H9c2 rat cardiac myoblast cell, whereas Co(II) and Ni(II) complexes on an average produced 19% cellular toxicity.


Assuntos
Acroleína/análogos & derivados , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Ergosterol/antagonistas & inibidores , Compostos Organometálicos/farmacologia , Acroleína/química , Acroleína/farmacologia , Animais , Antifúngicos/química , Candida/crescimento & desenvolvimento , Sobrevivência Celular/efeitos dos fármacos , Cobalto/química , Relação Dose-Resposta a Droga , Ergosterol/biossíntese , Ligantes , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mioblastos Cardíacos/citologia , Mioblastos Cardíacos/efeitos dos fármacos , Níquel/química , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Ratos , Estereoisomerismo , Relação Estrutura-Atividade
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