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1.
World J Microbiol Biotechnol ; 40(6): 188, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38702590

RESUMO

Methanol, the second most abundant volatile organic compound, primarily released from plants, is a major culprit disturbing atmospheric chemistry. Interestingly, ubiquitously found methanol-utilizing bacteria, play a vital role in mitigating atmospheric methanol effects. Despite being extensively characterized, the effect of nitrogen sources on the richness of methanol-utilizers in the bulk soil and rhizosphere is largely unknown. Therefore, the current study was planned to isolate, characterize and explore the richness of cultivable methylotrophs from the bulk soil and rhizosphere of a paddy field using media with varying nitrogen sources. Our data revealed that more genera of methylotrophs, including Methylobacterium, Ancylobacter, Achromobacter, Xanthobacter, Moraxella, and Klebsiella were enriched with the nitrate-based medium compared to only two genera, Hyphomicrobium and Methylobacterium, enriched with the ammonium-based medium. The richness of methylotrophic bacteria also differed substantially in the bulk soil as compared to the rhizosphere. Growth characterization revealed that majority of the newly isolated methanol-utilizing strains in this study exhibited better growth at 37 °C instead of 30 or 45 °C. Moreover, Hyphomicrobium sp. FSA2 was the only strain capable of utilizing methanol even at elevated temperature 45 °C, showing its adaptability to a wide range of temperatures. Differential carbon substrate utilization profiling revealed the facultative nature of all isolated methanol-utilizer strains with Xanthobacter sp. TS3, being an important methanol-utilizer capable of degrading toxic compounds such as acetone and ethylene glycol. Overall, our study suggests the role of nutrients and plant-microbial interaction in shaping the composition of methanol-utilizers in terrestrial environment.


Assuntos
Bactérias , Metanol , Nitrogênio , Oryza , Rizosfera , Microbiologia do Solo , Nitrogênio/metabolismo , Metanol/metabolismo , Oryza/microbiologia , Bactérias/classificação , Bactérias/metabolismo , Bactérias/isolamento & purificação , Solo/química , RNA Ribossômico 16S/genética , Filogenia , Minerais/metabolismo , Temperatura , Carbono/metabolismo
3.
Arch Microbiol ; 205(3): 88, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36781492

RESUMO

The present study reports the functionalization of antibiotic-conjugated Alternanthera pungens and Trichodesma indicum copper nanoparticles (CuNPs). Initially, antibiotic profiling of multi-drug resistant (MDR) clinical isolates against five antibiotics was verified and then gentamicin and ampicillin conjugates of CuNPs were prepared. Biosynthesized nanostructures were characterized through UV-visible spectroscopy, Fourier-transformed infrared spectroscopy, X-ray diffraction and scanning electron microscope. Biogenic synthesized CuNPs displayed highest antibacterial activity (24.0-31.3 mm inhibition zones) when capped with gentamicin as compared to the ampicillin-conjugated NPs which showed resistance against most of the bacterial species. A. pungens-derived conjugates of gentamicin (CuAp-GNT) along with the vehicle revealed 4.86 ± 0.20% and 4.25 ± 2.96% hemolytic potential and highest MDA production in S. typhimurium (3.18 ± 1.52 µg/mL and 6.31 ± 3.49 µg/mL) and K. pneumoniae (2.99 ± 0.90 µg/mL and 4.06 ± 1.20 µg/mL). Similarly, CuAp-GNT also showed highest DNA protection ability by displaying 1342.99 ± 11.87 band intensity. All-inclusive, CuAp showed more promising effects when conjugated with gentamicin indicating that capping of gentamicin with the active components of the plant-based copper nanostructures increases the antibacterial capacity of the drug. Hence, conjugation of antibiotics with bio-based sources offers great potential for identifying potent drug leads.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Cobre/farmacologia , Cobre/química , Gentamicinas/farmacologia , Nanopartículas Metálicas/química , Extratos Vegetais/química , Antibacterianos/farmacologia , Antibacterianos/química , Ampicilina/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Testes de Sensibilidade Microbiana
4.
J Basic Microbiol ; 60(5): 458-467, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32115731

RESUMO

Nanoparticles (NPs) are being recognized as antibacterial agents due to their rapidly increasing multidrug resistance in bacterial pathogens. Hence, there is an unmet need to identify the natural antibacterial agent. The present study aimed to evaluate the antibacterial activity of sericin-conjugated silver NPs synthesized by using sericin as a reducing and capping agent. Synthesized NPs were characterized by scanning electron microscope, nanolaser particle size analyzer (BT-90), Fourier-transform infrared analysis, and energy-dispersive X-ray. The biogenic NPs significantly inhibited the growth of Escherichia coli (12-15 mm zone of inhibition), Staphylococcus aureus (14.6-15.4 mm zone of inhibition), and Klebsiella pneumoniae (12.5-18 mm zone of inhibition). The stability of naturally synthesized NPs was examined at various temperatures (i.e., 4°C, 37°C, and 55°C) and pH (i.e., 3, 7, and 11). Temperature variability did not significantly affect the efficacy of NPs. However, NPs performed better at higher pH levels. This study suggested that the sericin-based silver NPs are not only effective against bacteria, but they also maintain the stability at different ranges of temperature and pH. We concluded that the sericin-conjugated silver NPs possess the remarkable antibacterial potential, which suggests their large-scale use as a cheap and stable antimicrobial agent in the future.


Assuntos
Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Sericinas/química , Prata/química , Animais , Antibacterianos/química , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bombyx , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Nanoconjugados/química , Prata/farmacologia , Temperatura
5.
Phys Chem Chem Phys ; 20(33): 21573-21579, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30095137

RESUMO

We report an experimental study of water clusters as guests in interactions with clusters of adamantane (Ad) as hosts that occur in doped helium droplets at extremely low temperatures. Separate experiments with pure water as dopant showed ready formation of a distribution of water clusters (H2O)mH+ that peaks at m = 11 and extends beyond m = 100 with local maxima at m = 4, 11, 21, 28 and 30 with (H2O)21H+ being the most anomalous and showing the greatest stability with respect to clusters immediately adjacent in water content. When adamantane is also added as a dopant, extensive hydration is seen in the formation of water/adamantane clusters, (H2O)mAdn+; magic number clusters (H2O)21Adn+ are seen for all the adamantane clusters. Other magic numbers for water clusters attached to adamantane, (H2O)mAdn+, are as for pristine protonated water, with m = 28 and m = 30. The icosahedral shell closure of pure adamantane at n = 13 and 19 appears to be preserved with (H2O)21 replacing one adamantane. (H2O)21Ad12+ and (H2O)21Ad18+ stand out in intensity and demonstrate the interplay of magic number water clusters with magic number adamantane clusters, observed perhaps for the first time in gas-phase cluster chemistry. There was no clear evidence for the formation of clathrate hydrates in which adamantane is trapped within structured water.

6.
Cureus ; 9(10): e1751, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-29226041

RESUMO

Sodium-glucose co-transporter 2 inhibitors (SGLT2is) such as dapagliflozin, canagliflozin, and empagliflozin, are a promising new therapy in the treatment of type 2 diabetes mellitus (T2DM). SGLT2is can effectively reduce hyperglycemia thus improving glycemic control and they offer some beneficial effects on the cardiovascular (CV) system which can benefit patients with heart failure in addition toT2DM. The United States Food and Drug Administration requires new diabetes mellitus therapies to show a CV safety profile. Empagliflozin was the first SGLT2i that, when added to the standard of care for patients withT2DM at high risk for CV events, showed improved CV outcomes including reduced deaths from CV causes. Evidence also exists in favor of dapagliflozin for use in patients with T2DM with CV risk factors and heart failure. This review focuses on the effects, safety, and benefits of dapagliflozin on the CV system. Clinical trials have shown that dapagliflozin improves glycemic control without variation. It is safe and well-tolerated in the general population including older patients and those with high-risk CV factors or preexisting CV disease. There may be a renal protective role by an unknown mechanism. Dapagliflozin also lowers blood pressure due to its natriuresis effect. It improves levels of visceral fat and reduces body weight, and thus ameliorates metabolic syndrome. Dapagliflozin reduces oxidative stress and may delay atherosclerosis. Recent findings indicate SGLT2is may also reduce the atrial natriuretic peptide levels. Additional trials are required to validate these benefits and further evaluate if these are class effects. Trials such as DECLARE-TIMI58 are ongoing to evaluate the CV outcomes of dapagliflozin. More research is needed to design better antihyperglycemic regimes with clinical benefits in addition to good glycemic control.

7.
Cureus ; 9(12): e1984, 2017 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-29503778

RESUMO

Transgender or gender dysphoria has been defined in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), as distress resulting from the incongruence between one's experienced gender and one's assigned gender, along with a persistent and strong desire to be of another gender, and accompanied by clinically significant distress. Adolescents referred for evaluation often want hormonal therapy and several among them also express a desire for gender reassignment surgery. Furthermore, evidence shows that adolescents and adults with gender dysphoria without a sex development disorder, before gender reassignments, are at increased risk for suicide. For this review, a search of the English language scientific literature was conducted using the PubMed database. This summary discusses the associations and comorbidities of gender dysphoria and reiterates the evidence that its etiology is multifactorial. Transsexualism involves prenatal neuroanatomical changes, has a psychiatric association, and is found to be more prevalent in conjunction with schizophrenia and autism spectrum disorders. Childhood adversities and neglect are also linked to having a transgender identity. Moreover, the evidence favors a genetic predisposition. Likewise, there seems to be a growing concern with regards to the relationship between endocrine disruptors and transsexuals as well as other gender minority populations. More research needs to be done to understand the exact pathways.

8.
Cureus ; 9(11): e1844, 2017 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-29344438

RESUMO

Polycystic ovary syndrome (PCOS) is a pathophysiological disorder affecting reproductive and metabolic indices. PCOS is commonly associated with a high prevalence of insulin resistance and obesity; this association carries an increased risk of developing metabolic syndrome, type 2 diabetes mellitus (T2DM), and cardiovascular disease. Guidelines recommend lifestyle modification, metformin, hormonal contraceptives (HCs), and bariatric surgery as the main treatment options in obese patients with PCOS. Studies are being conducted to test the efficacy of existing treatment options as well as to discover new therapies. This review focuses on the most recent advances in this regard and highlights new hypotheses and emerging studies to give a picture of the latest therapeutic trends in the treatment of obese patients with PCOS. In this respect, much attention is given to the role of inositols, the mediators of insulin action. A deficiency of d-chiro-inositol containing inositol-phospho-glycans may be the basis of insulin resistance frequently seen in PCOS patients. Moreover, evidence suggests the use of statins in obese women with PCOS, but guidelines call for further research. Adiponectin, quercetin, vitamin D, and anti-obesity drugs have also been studied and seem to have a useful role in the treatment of obesity and metabolic syndrome in PCOS. Many trials have been conducted on the use of non-pharmacological therapies. Therapies including resveratrol, acupuncture, and berberine have favorable effects in overweight PCOS patients. However, more research is needed to reveal the clinical complexity of PCOS and develop more effective treatment options.

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