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1.
Microbiol Spectr ; : e0042724, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39082827

RESUMEN

In the era of antimicrobial resistance, phage-antibiotic combinations offer a promising therapeutic option, yet research on their synergy and antagonism is limited. This study aims to assess these interactions, focusing on protein synthesis inhibitors and cell envelope-active agents against multidrug-resistant bacterial strains. We evaluated synergistic and antagonistic interactions in multidrug-resistant Staphylococcus aureus, Enterococcus faecium, and Pseudomonas aeruginosa strains. Phages were combined with protein synthesis inhibitors [linezolid (LZD), minocycline (MIN), gentamicin (GEN), and azithromycin (AZM)] or cell envelope-active agents [daptomycin (DAP), ceftaroline (CPT), and cefepime (FEP)]. Modified checkerboard minimum inhibitory concentration assays and 24-h time-kill analyses were conducted, alongside one-step growth curves to analyze phage growth kinetics. Statistical comparisons used one-way analysis of variance (ANOVA) and the Tukey test (P < 0.05). In the checkerboard and 24-h time-kill analyses (TKA) of S. aureus and E. faecium, phage-LZD and phage-MIN combinations were antagonistic (FIC > 4) while phage-DAP and phage-CPT were synergistic (FIC 0.5) (ANOVA range of mean differences 0.52-2.59 log10 CFU/mL; P < 0.001). For P. aeruginosa, phage-AZM was antagonistic (FIC > 4), phage-GEN was additive (FIC = 1), and phage-FEP was synergistic (ANOVA range of mean differences 1.04-1.95 log10 CFU/mL; P < 0.001). Phage growth kinetics were altered in the presence of LZD and MIN against S. aureus and in the presence of LZD against a single E. faecium strain (HOU503). Our findings indicate that select protein synthesis inhibitors may induce phage-antibiotic antagonism. However, this antagonism may not solely stem from changes in phage growth kinetics, warranting further investigation into the complex interplay among strains, phage attributes, and antibiotic mechanisms affecting bacterial inhibition.IMPORTANCEIn the face of escalating antimicrobial resistance, combining phages with antibiotics offers a promising avenue for treating infections unresponsive to traditional antibiotics. However, while studies have explored synergistic interactions, less attention has been given to potential antagonism and its impact on phage growth kinetics. This research evaluates the interplay between phages and antibiotics, revealing both synergistic and antagonistic patterns across various bacterial strains and shedding light on the complex dynamics that influence treatment efficacy. Understanding these interactions is crucial for optimizing combination therapies and advancing phage therapy as a viable solution for combating antimicrobial resistance.

2.
J Immunol ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39082935

RESUMEN

Calcitriol, the bioactive form of vitamin D, exerts its biological functions by binding to its cognate receptor, the vitamin D receptor (VDR). The indicators of the severity of allergies and asthma have been linked to low vitamin D levels. However, the role of calcitriol in regulating IL-4 and IL-13, two cytokines pivotal to allergic inflammation, remained unclear. Our study observed diminished IL-4 and IL-13 secretion in murine and human Th2 cells treated with calcitriol. In murine Th2 cells, Gata3 expression was attenuated by calcitriol. However, the expression of the transcriptional repressor Gfi1, too, was attenuated in the presence of calcitriol. Ectopic expression of either Gfi1 or VDR impaired the secretion of IL-13 in Th2 cells. In murine Th2 cells, VDR interacted with Gata3 but not Gfi1. Gfi1 significantly impaired Il13 promoter activation, which calcitriol failed to restore. Conversely, calcitriol augmented Gfi1 recruitment to the Il13 promoter. Ecr, a conserved region between these two genes, which enhanced the transactivation of Il4 and Il13 promoters, is essential for calcitriol-mediated suppression of both the genes. Calcitriol augmented the recruitment of VDR to the Il13 promoter and Ecr regions. Gata3 recruitment was significantly impaired at the Il13 and Ecr loci in the presence of calcitriol but increased at the Il4 promoter. Furthermore, the recruitment of the histone deacetylase HDAC1 was universally increased at the promoters of Il4, Il13, and Ecr when calcitriol was present. Together, our data clearly elucidate that calcitriol modulates VDR, Gata3, and Gfi1 to suppress IL-4 and IL-13 production in Th2 cells.

3.
Sci Rep ; 14(1): 12952, 2024 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-38839775

RESUMEN

To date, degraded mangrove ecosystem restoration accomplished worldwide primarily aligns towards rehabilitation with monotypic plantations, while ecological restoration principles are rarely followed in these interventions. However, researchers admit that most of these initiatives' success rate is not appreciable often. An integrative framework of ecological restoration for degraded mangroves where site-specific observations could be scientifically rationalized, with co-located reference pristine mangroves as the target ecosystem to achieve is currently distinctively lacking. Through this experimental scale study, we studied the suitability of site-specific strategies to ecologically restore degraded mangrove patches vis-à-vis the conventional mono-species plantations in a highly vulnerable mangrove ecosystem in Indian Sundarbans. This comprehensive restoration framework was trialed in small discrete degraded mangrove patches spanning ~ 65 ha. Site-specific key restoration components applied are statistically validated through RDA analyses and Bayesian t-tests. 25 quantifiable metrics evaluate the restoration success of a ~ 3 ha degraded mangrove patch with Ridgeline distribution, Kolmogorov-Smirnov (K-S) tests, and Mahalanobis Distance (D2) measure to prove the site's near-equivalence to pristine reference in multiple ecosystem attributes. This restoration intervention irrevocably establishes the greater potential of this framework in the recovery of ecosystem functions and self-sustenance compared to that of predominant monoculture practices for vulnerable mangroves.


Asunto(s)
Conservación de los Recursos Naturales , Humedales , India , Conservación de los Recursos Naturales/métodos , Ecosistema , Restauración y Remediación Ambiental/métodos , Proyectos Piloto , Teorema de Bayes
4.
Front Microbiol ; 15: 1324188, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38873137

RESUMEN

Introduction: Biological nitrogen fixation (BNF), an unparalleled metabolic novelty among living microorganisms on earth, globally contributes ~88-101 Tg N year-1 to natural ecosystems, ~56% sourced from symbiotic BNF while ~22-45% derived from free-living nitrogen fixers (FLNF). The success of symbiotic BNF is largely dependent on its interaction with host-plant, however ubiquitous environmental heterotrophic FLNFs face many limitations in their immediate ecological niches to sustain unhindered BNF. The autotrophic FLNFs like cyanobacteria and oceanic heterotrophic diazotrophs have been well studied about their contrivances acclimated/adapted by these organisms to outwit the environmental constraints for functional diazotrophy. However, FLNF heterotrophs face more adversity in executing BNF under stressful estuarine/marine/aquatic habitats. Methods: In this study a large-scale cultivation-dependent investigation was accomplished with 190 NCBI accessioned and 45 non-accessioned heterotrophic FLNF cultivable bacterial isolates (total 235) from halophilic estuarine intertidal mangrove niches of Indian Sundarbans, a Ramsar site and UNESCO proclaimed World Heritage Site. Assuming ~1% culturability of the microbial community, the respective niches were also studied for representing actual bacterial diversity via cultivation-independent next-generation sequencing of V3-V4 rRNA regions. Results: Both the studies revealed a higher abundance of culturable Gammaproteobacteria followed by Firmicutes, the majority of 235 FLNFs studied belonging to these two classes. The FLNFs displayed comparable selection potential in media for free nitrogen fixers and iron-oxidizing bacteria, linking diazotrophy with iron oxidation, siderophore production, phosphorus solubilization, phosphorus uptake and accumulation as well as denitrification. Discussion: This observation validated the hypothesis that under extreme estuarine mangrove niches, diazotrophs are naturally selected as a specialized multidimensional entity, to expedite BNF and survive. Earlier metagenome data from mangrove niches demonstrated a microbial metabolic coupling among C, N, P, S, and Fe cycling in mangrove sediments, as an adaptive trait, evident with the co-abundant respective functional genes, which corroborates our findings in cultivation mode for multiple interrelated metabolic potential facilitating BNF in a challenging intertidal mangrove environment.

5.
Cureus ; 16(5): e60152, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38864043

RESUMEN

INTRODUCTION: People with visual impairments and blindness face challenges in performing regular tasks such as maintaining proper sanitation, which makes them vulnerable to intestinal parasitic infections. AIMS AND OBJECTIVES: This study aims to examine the prevalence and distribution of intestinal parasitic infections in children and adolescents with ocular diseases and to assess if the lockdown during the COVID-19 pandemic affected these rates. METHODS: This retrospective, hospital record-based study was conducted among children and adolescents attending the Regional Institute of Ophthalmology in Kolkata, India. It involved routine stool examinations as part of their treatment during 2019-2020. Early morning stool specimens were collected and brought to the institute laboratory in containers. Stools were examined under a microscope for cysts, ova, parasites, and adult worms. Findings were recorded in the laboratory record book. These data were then extracted into a spreadsheet and analyzed using IBM SPSS Statistics for Windows, Version 26 (Released 2019; IBM Corp., Armonk, New York). RESULTS: The prevalence of intestinal parasitic infections was 8.59% (59 out of 687 patients). Among those 59 positive cases, Ascaris lumbricoides, Giardia lamblia, Entamoeba histolytica, Trichuris trichiura, Taenia spp., Enterobius vermicularis, and Isospora belli were detected in 27 (45.8%), 15 (25.4%), 8 (13.6%), 6 (10.2%), 3 (5.1%), 2 (3.4%), and 1 (1.7%) patients, respectively. The positivity rate of stool samples was higher from September and thereafter from January to March. The sample positivity rate was higher post-pandemic and lockdown, but not statistically significant (11.5% vs. 5.3%; χ²=4.044, df=1, p=0.44). CONCLUSION: Ascaris lumbricoides was the most commonly observed intestinal parasite in children and adolescents with ocular disease in our setting. Seasonal variation was noted with higher case positivity at the end of the rainy season and thereafter in winter. Therefore, we propose to strengthen the routine deworming program during this period in Eastern India. Higher sample positivity after the pandemic may be attributed to school closures during the lockdown period, which might have caused some children to miss their routine deworming medication.

6.
Antimicrob Agents Chemother ; 68(4): e0172823, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38470133

RESUMEN

Left ventricular assist devices (LVAD) are increasingly used for management of heart failure; infection remains a frequent complication. Phage therapy has been successful in a variety of antibiotic refractory infections and is of interest in treating LVAD infections. We performed a retrospective review of four patients that underwent five separate courses of intravenous (IV) phage therapy with concomitant antibiotic for treatment of endovascular Pseudomonas aeruginosa LVAD infection. We assessed phage susceptibility, bacterial strain sequencing, serum neutralization, biofilm activity, and shelf-life of phage preparations. Five treatments of one to four wild-type virulent phage(s) were administered for 14-51 days after informed consent and regulatory approval. There was no successful outcome. Breakthrough bacteremia occurred in four of five treatments. Two patients died from the underlying infection. We noted a variable decline in phage susceptibility following three of five treatments, four of four tested developed serum neutralization, and prophage presence was confirmed in isolates of two tested patients. Two phage preparations showed an initial titer drop. Phage biofilm activity was confirmed in two. Phage susceptibility alone was not predictive of clinical efficacy in P. aeruginosa endovascular LVAD infection. IV phage was associated with serum neutralization in most cases though lack of clinical effect may be multifactorial including presence of multiple bacterial isolates with varying phage susceptibility, presence of prophages, decline in phage titers, and possible lack of biofilm activity. Breakthrough bacteremia occurred frequently (while the organism remained susceptible to administered phage) and is an important safety consideration.


Asunto(s)
Bacteriemia , Bacteriófagos , Corazón Auxiliar , Terapia de Fagos , Infecciones por Pseudomonas , Humanos , Pseudomonas aeruginosa , Corazón Auxiliar/efectos adversos , Infecciones por Pseudomonas/terapia , Infecciones por Pseudomonas/microbiología , Antibacterianos/uso terapéutico , Profagos , Bacteriemia/tratamiento farmacológico
7.
Cytokine ; 173: 156440, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37984154

RESUMEN

17-ß Estradiol (E2) has long standing known functions in regulating human physiology as well as immune system. E2 is known to elicit a protective role against experimental autoimmune encephalomyelitis (EAE) and has been used as a drug for treatment against multiple sclerosis. Moreover, E2 regulates the adaptive immune system by directly affecting the T helper cell subsets differentiation and antibody secretion mediated by B cells. Reports have shown that E2 promotes Th1 and Treg cell differentiation; whereas it attenuated the Th17 and Tfh cell differentiation. Albeit multiple and contrasting studies, the mechanisms of behind E2 action on Th2 cells remained understudied. Hence, we sought to dissect the impact of E2 in Th2 cell differentiation. In this study, we elucidated the molecular mechanisms behind E2-mediated regulation of the differentiation of Th2 cells. We observed that E2 significantly attenuated the IL-4-secreting Th2 population in an ERα-dependent manner. We validated these findings using ICI 182, 780, an antagonist to ERα, not ERß and ectopically overexpressing ERα in Th2 cells. We further determined that ERα alters the recruitment of GATA3 and PU.1 to Il4 gene by directly interacting with them. This altered recruitment was observed to be stronger at Il4 than Il13 locus. Interestingly, we detected a distinct recruitment of GATA3 and PU.1 at Il13 gene; however, there was no E2-mediated broad alteration in the recruitment of histone-modifiers at Il13 locus. These findings suggest that E2 regulates Il4 in a distinctly separate mechanism as opposed to Il13 locus in Th2 cells.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Células Th2 , Animales , Humanos , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Estradiol/farmacología , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Diferenciación Celular , Células TH1 , Células Th17/metabolismo , Factor de Transcripción GATA3/genética , Factor de Transcripción GATA3/metabolismo
8.
Cells ; 12(21)2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37947635

RESUMEN

As Australian lupin cultivars are rich sources of polyphenols, dietary fibers, high-quality proteins, and abundant bioactive compounds with significant antioxidant, antidiabetic, and anticancer activities, this research work is aimed at investigating the colon cancer alleviation activity of nine cultivars of lupin seeds on HCT116 and HT29 colon carcinoma cell lines through anti-proliferation assay, measurement of apoptosis, and identification of the mechanism of apoptosis. Nine cultivars were pre-screened for anti-proliferation of HCT116 and HT29 cells along with consideration of the impact of heat processing on cancer cell viability. Mandelup and Jurien showed significant inhibition of HCT116 cells, whereas the highest inhibition of HT29 cell proliferation was attained by Jurien and Mandelup. Processing decreased the anti-proliferation activity drastically. Lupin cultivars Mandelup, Barlock, and Jurien (dose: 300 µg/mL) induced early and late apoptosis of colon cancer cells in Annexin V-FITC assay. The mechanism of apoptosis was explored, which involves boosting of caspases-3/7 activation and intracellular reactive oxygen species (ROS) generation in HCT116 cells (Mandelup and Barlock) and HT29 cells (Jurien and Mandelup). Thus, the findings showed that lupin cultivars arrest cell cycles by inducing apoptosis of colorectal carcinoma cells triggered by elevated ROS generation and caspases-3/7 activation.


Asunto(s)
Apoptosis , Neoplasias del Colon , Humanos , Especies Reactivas de Oxígeno/metabolismo , Australia , Neoplasias del Colon/patología , Células HCT116 , Caspasas/metabolismo
9.
Phys Chem Chem Phys ; 25(35): 23963-23976, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37644802

RESUMEN

The liquid structure of systems wherein water is limited in concentration or through geometry is of great interest in various fields such as biology, materials science, and electrochemistry. Here, we present a combined polarized Raman and molecular dynamics investigation of the structural changes that occur as water is added incrementally to propylene carbonate (PC), a polar, aprotic solvent that is important in lithium-ion batteries. Polarized Raman spectra of PC solutions were collected for water mole fractions 0.003 ≤ χwater ≤ 0.296, which encompasses the solubility range of water in PC. The novel approach taken herein provides additional hydrogen bond and solvation characterization of this system that has not been achievable in previous studies. Analysis of the polarized carbonyl Raman band in conjunction with simulations demonstrated that the bulk structure of the solvent remained unperturbed upon the addition of water. Experimental spectra in the O-H stretching region were decomposed through Gaussian fitting into sub-bands and comparison to studies of dilute HOD in D2O. With the aid of simulations, we identified these different bands as water arrangements having different degrees of hydrogen bonding. The observed water structure within PC indicates that water tends to self-aggregate, forming a hydrogen bond network that is distinctly different from the bulk and dependent on concentration. For example, at moderate concentrations, the most likely aggregate structures are chains of water molecules, each with two hydrogen bonds.

10.
Heliyon ; 9(6): e16985, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37292329

RESUMEN

Background: Hyper-inflammatory immune response of SARS-CoV-2 is often characterized by the release of multiple pro-inflammatory cytokines with an impact on the expression of numerous other interleukins (ILs). However, from oral and nasal swab samples the specific quantitative association of the different IL-markers with the disease progression and its relationship with the status of vaccination remains unclear. Materials and methods: Patients' combined oral and nasal swab samples were collected from both non-vaccinated and double-vaccinated individuals with high (Ct value < 25) and low (Ct value > 30) viral loads, along with uninfected donors. None of the patients were critically ill, or needed ICU support. The expression of different cytokines (IL6, IL10, IL1B, IFNG) and mucin (MUC5AC, MUC1) markers were assessed between different groups by qRT-PCR. The important cytokine markers differentiating between vaccinated and non-vaccinated patients were identified by PCA. Conclusion: IL6 expression was higher in non-vaccinated COVID-19 patients infected with delta-variant irrespective of their viral-load compared to uninfected individuals. However, in double-vaccinated patients, only in high viral-load patients (Ct value < 25), IL6 expression increased. In high viral-load patients, irrespective to their vaccination status, IL10 expression was lower compared to the uninfected control group. Surprisingly, IL10 expression was lower in double-vaccinated patients with Ct value > 30. IL1B, and IFNG expression remained unaltered in uninfected and infected individuals. However, MUC5AC expression was lower in non-vaccinated patients with Ct value < 25 compared to control group. Our study unveiled that IL10/IL6 ratio can be used as a biomarker for COVID-19 patients upon proper establishment of it in a clinical setting.

11.
Microbiol Spectr ; 11(4): e0034023, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37338375

RESUMEN

Enterococcus faecium is a difficult-to-treat pathogen with emerging resistance to most clinically available antibiotics. Daptomycin (DAP) is the standard of care, but even high DAP doses (12 mg/kg body weight/day) failed to eradicate some vancomycin-resistant strains. Combination DAP-ceftaroline (CPT) may increase ß-lactam affinity for target penicillin binding proteins (PBP); however, in a simulated endocardial vegetation (SEV) pharmacokinetic/pharmacodynamic (PK/PD) model, DAP-CPT did not achieve therapeutic efficacy against a DAP-nonsusceptible (DNS) vancomycin-resistant E. faecium (VRE) isolate. Phage-antibiotic combinations (PAC) have been proposed for resistant high-inoculum infections. We aimed to identify PAC with maximum bactericidal activity and prevention/reversal of phage and antibiotic resistance in an SEV PK/PD model against DNS isolate R497. Phage-antibiotic synergy (PAS) was evaluated with modified checkerboard MIC and 24-h time-kill analyses (TKA). Human-simulated antibiotic doses of DAP and CPT with phages NV-497 and NV-503-01 were then evaluated in 96-h SEV PK/PD models against R497. Synergistic and bactericidal activity was identified with the PAC of DAP-CPT combined with phage cocktail NV-497-NV-503-01, demonstrating a significant reduction in viability down to 3-log10 CFU/g (-Δ, 5.77-log10 CFU/g; P < 0.001). This combination also demonstrated isolate resensitization to DAP. Evaluation of phage resistance post-SEV demonstrated prevention of phage resistance for PACs containing DAP-CPT. Our results provide novel data highlighting bactericidal and synergistic activity of PAC against a DNS E. faecium isolate in a high-inoculum ex vivo SEV PK/PD model with subsequent DAP resensitization and prevention of phage resistance. IMPORTANCE Our study supports the additional benefit of standard-of-care antibiotics combined with a phage cocktail compared to antibiotic alone against a daptomycin-nonsusceptible (DNS) E. faecium isolate in a high-inoculum simulated endocardial vegetation ex vivo PK/PD model. E. faecium is a leading cause of hospital-acquired infections and is associated with significant morbidity and mortality. Daptomycin is considered the first-line therapy for vancomycin-resistant E. faecium (VRE), but the highest published doses have failed to eradicate some VRE isolates. The addition of a ß-lactam to daptomycin may result in synergistic activity, but previous in vitro data demonstrate that daptomycin plus ceftaroline failed to eradicate a VRE isolate. Phage therapy as an adjunct to antibiotic therapy has been proposed as a salvage therapy for high-inoculum infections; however, pragmatic clinical comparison trials for endocarditis are lacking and difficult to design, reinforcing the timeliness of such analysis.


Asunto(s)
Daptomicina , Enterococcus faecium , Humanos , Antibacterianos/farmacología , Daptomicina/farmacología , Vancomicina/farmacología , beta-Lactamas/farmacología , Pruebas de Sensibilidad Microbiana , Ceftarolina
12.
Heliyon ; 9(3): e14254, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36938384

RESUMEN

Ceriops decandra (Griff.) (CD) and Ceriops tagal (Perr.) (CT) are two mangrove plants of the Sundarbans distributed along the coastal areas of South Asia and South Pacific Africa. Traditionally, these plants are used to treat diabetes, pain, angina, hemorrhage, and ulcer. In this study, we investigated the antioxidative, antihyperglycemic, analgesic, and anti-inflammatory potential of the aerial roots of CD and CT. At first, the antioxidative potential of CD and CT ethanolic extracts were investigated qualitatively and quantitatively by 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical and hydrogen peroxide scavenging assays and by determining total antioxidant capacity. The total phenolic, flavonoid, tannin, and terpenoid contents of CD and CT were also estimated. The extracts' antihyperglycemic, analgesic, and anti-inflammatory potential were evaluated by oral glucose tolerance test, acetic acid-induced writhing test, and formaldehyde-induced paw-edema test, respectively. In vitro α-glucosidase and α-amylase enzyme inhibitory activities were also assessed. The CD and CT extracts were also analyzed using GCMS for the presence of phytochemicals. Then, molecular docking was carried out with α-glucosidase, α-amylase, cyclooxygenase-II (COX-II), 3-lipoxygenase (3-LOX) enzymes using the compounds found in GCMS analysis as well as the previously reported compounds from CD and CT. Finally, the pharmacokinetic and toxicological profiles of eight selected compounds were assessed with SwissADME and admetSAR server. In the antioxidative, antihyperglycemic, analgesic, and anti-inflammatory activity tests, CT extract showed a greater potential than CD extract. In addition, CT extract demonstrated higher α-glucosidase enzyme inhibitory activity in comparison to CD extract although CD extract exhibited better α-amylase enzyme inhibitory activity. Molecular docking studies revealed the presence of potentially bioactive compounds in both CD and CT. 2-(2-methylphenyl)-1-phenyl-(z)-1-propene of CD demonstrated good binding affinities for α-glucosidase, COX-II, and 3-LOX. In addition, 5S*,8S*,9S*,10R*,13S*)-18-hydroxy-16-nor-3-oxodolabr-4(18)-en-15-oic acid had high binding interactions for both α-glucosidase and α-amylase while 2',5,5'-tetramethyl-1,1'-biphenyl, 2-methyl-4-(3'-phenylpropyl)piperidine and decandrin C had high binding interactions for both COX-II and 3-LOX. Finally, 5S*,8S*,9S*,10R*,13S*)-18-hydroxy-16-nor-3-oxodolabr-4(18)-en-15-oic acid, decandrin C, 2-(2-methylphenyl)-1-phenyl-(z)-1-propene and 2-methyl-4-(3'-phenylpropyl)piperidine demonstrated better pharmacokinetic and toxicological properties in the ADMET analysis compared to the others. Hence it can be concluded that the present study supports the traditional usage of CD and CT for diabetes and pain and reveals the presence of bioactive phytochemicals in both.

13.
Pediatr Infect Dis J ; 42(1): 43-46, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36201671

RESUMEN

INTRODUCTION: Treating recurrent multidrug resistant (MDR) urosepsis in pediatric transplant recipients can be challenging. Particularly when antibiotics fail to prevent future occurrence and the nidus is seemingly undiscoverable. While there is an increasing amount of data on phage therapy, to our knowledge, there are no published cases involving pediatric renal transplant recipients. Therefore, we present a challenging clinical case in which phage therapy was used in a pediatric renal transplant recipient who developed recurrent MDR urosepsis with an unclear source. CASE PRESENTATION: Our patient was a 17-year-old female who initially developed urosepsis caused by extended-spectrum ß-lactamase (ESBL) Escherichia coli , while being treated with an immunosuppressant regimen because of kidney rejection secondary to poor immunosuppression therapy compliance. She was admitted to our hospital intermittently for 4 months with 4 episodes of urosepsis caused by ESBL E. coli . She received multiple courses of antibiotics (mainly ertapenem) and underwent a fecal material transplant to eradicate her ESBL E. coli colonized gastrointestinal tract. Because of recurrent development of urosepsis after antibiotic treatment, she later underwent treatment with a phage cocktail consisting of 2 isolate-specific phages. After a prolonged antibiotic course and subsequent 3-week intravenous phage treatment, she had no ESBL E. coli in her urinary cultures for 4 years post-treatment. DISCUSSION: This case highlights the challenges of treating recurrent ESBL E. coli infections in a pediatric renal transplant patient and provides evidence that phage therapy may prove useful in such cases.


Asunto(s)
Trasplante de Riñón , Terapia de Fagos , Humanos , Niño , Adolescente , Escherichia coli , Antibacterianos/uso terapéutico , Trasplante de Riñón/efectos adversos
14.
Mil Med ; 188(3-4): e463-e467, 2023 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-34179992

RESUMEN

INTRODUCTION: Staphylococcus aureus (SA) is a major human bacterial pathogen increasingly refractory to antibiotics. Given the dearth of novel antibiotics in the developmental pipeline, we require concerted efforts at optimizing novel antimicrobial approaches. One promising option is the utilization of bacteriophage (phage) therapy, which has been resurrected as a viable clinical therapeutic. Specifically, an expanded library of phages targeting SA is desired. We surmised that SA-targeting phages would be readily accessible as a major component of the cutaneous microbiome. Specifically, we sought to discern if easily accessible (convenient) and discrete anatomic locations, including the nares, axilla, fingernails, toenails, and web spaces, could provide intact phages via a noninvasive, expedient procedure involving swabbing. METHODS: One hundred subjects participated in systematic skin swab specimen collections. Pooled samples were subject to phage harvesting utilizing the soft agar overlay technique. The approval was secured from the Naval Medical Research Center Institutional Review Board (NMRC 2018.0004 FWA00000152). We utilized the same procedures from known samples containing SA-targeting phages. As another positive control, we employed the same swab and acquired samples from an active wound infection. RESULTS: As anticipated, there were no adverse events, and the procedure was successfully implemented within the projected 10-minute duration. No phages were identified exploiting this methodology. Positive controls from various environmental samples identified SA-targeting phages as did the wound effluent sample. CONCLUSIONS: Skin swabbing at multiple anatomic sites from 100 adults yielded insufficient biomass for phage recovery. The negative results provide helpful information for future phage isolation attempts. The lessons learned on why this study failed to isolate phages can be easily utilized by others. With a desire to increase our SA-targeting phage library in pursuit of future clinical trials, and acknowledging the paucity of these phages accessible via traditional recovery from environmental sources, we will next acquire large volumes of wound effluent from confirmed infected wounds with SA to optimize the biomass for phage recovery.


Asunto(s)
Bacteriófagos , Infecciones Estafilocócicas , Adulto , Humanos , Staphylococcus aureus , Infecciones Estafilocócicas/terapia , Antibacterianos , Fagos de Staphylococcus
15.
Antibiotics (Basel) ; 11(9)2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-36139953

RESUMEN

Multidrug-resistant (MDR) Enterococcus faecium is a challenging nosocomial pathogen known to colonize medical device surfaces and form biofilms. Bacterio (phages) may constitute an emerging anti-infective option for refractory, biofilm-mediated infections. This study evaluates eight MDR E. faecium strains for biofilm production and phage susceptibility against nine phages. Two E. faecium strains isolated from patients with bacteremia and identified to be biofilm producers, R497 (daptomycin (DAP)-resistant) and HOU503 (DAP-susceptible dose-dependent (SDD), in addition to four phages with the broadest host ranges (ATCC 113, NV-497, NV-503-01, NV-503-02) were selected for further experiments. Preliminary phage-antibiotic screening was performed with modified checkerboard minimum biofilm inhibitory concentration (MBIC) assays to efficiently screen for bacterial killing and phage-antibiotic synergy (PAS). Data were compared by one-way ANOVA and Tukey (HSD) tests. Time kill analyses (TKA) were performed against R497 and HOU503 with DAP at 0.5× MBIC, ampicillin (AMP) at free peak = 72 µg/mL, and phage at a multiplicity of infection (MOI) of 0.01. In 24 h TKA against R497, phage-antibiotic combinations (PAC) with DAP, AMP, or DAP + AMP combined with 3- or 4-phage cocktails demonstrated significant killing compared to the most effective double combination (ANOVA range of mean differences 2.998 to 3.102 log10 colony forming units (CFU)/mL; p = 0.011, 2.548 to 2.868 log10 colony forming units (CFU)/mL; p = 0.023, and 2.006 to 2.329 log10 colony forming units (CFU)/mL; p = 0.039, respectively), with preserved phage susceptibility identified in regimens with 3-phage cocktails containing NV-497 and the 4-phage cocktail. Against HOU503, AMP combined with any 3- or 4-phage cocktail and DAP + AMP combined with the 3-phage cocktail ATCC 113 + NV-497 + NV-503-01 demonstrated significant PAS and bactericidal activity (ANOVA range of mean differences 2.251 to 2.466 log10 colony forming units (CFU)/mL; p = 0.044 and 2.119 to 2.350 log10 colony forming units (CFU)/mL; p = 0.028, respectively), however, only PAC with DAP + AMP maintained phage susceptibility at the end of 24 h TKA. R497 and HOU503 exposure to DAP, AMP, or DAP + AMP in the presence of single phage or phage cocktail resulted in antibiotic resistance stabilization (i.e., no antibiotic MBIC elevation compared to baseline) without identified antibiotic MBIC reversion (i.e., lowering of antibiotic MBIC compared to baseline in DAP-resistant and DAP-SDD isolates) at the end of 24 h TKA. In conclusion, against DAP-resistant R497 and DAP-SDD HOU503 E. faecium clinical blood isolates, the use of DAP + AMP combined with 3- and 4-phage cocktails effectively eradicated biofilm-embedded MDR E. faecium without altering antibiotic MBIC or phage susceptibility compared to baseline.

16.
Saudi J Biol Sci ; 29(7): 103312, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35663844

RESUMEN

The aim of this study is to assess the antioxidative profile and related pharmacological potentialities of the ethanolic extract of Amischotolype mollissima leaves, traditionally used in treating pain, injury, malarial fever, epilepsy and hyperacidity, followed by a computational approach for the analysis of bioactive compounds identified by GC-MS. In GC-MS analysis, the extract yielded ten compounds, with 4,6-di-t-butyl-2-alpha-methyl benzyl phenol having the highest amount. In vitro investigation of the antioxidative properties of the plant was conducted with 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical and hydrogen peroxide scavenging assays. The amounts of secondary metabolites phenolics, flavonoids, and tannins were measured at 142 mg GAE/g, 534 mg QE/g, and 110 mg GAE/g, respectively. An acute toxicity study was carried out on mice, which revealed no toxicity up to the dosage of 4000 mg/kg bw. For the dosages of extract at 250 and 500 mg/kg bw, the writhing response test induced by acetic acid exhibited a statistically significant (p < 0.05) analgesic effect in mice. The oral glucose tolerance test (OGTT) and alpha-glucosidase enzyme inhibitory activity assay were used to examine the antihyperglycemic potential, in which the extract reduced the blood glucose level to 6.22 mmol/l and 3.82 mmol/l, at dosages of 250 and 500 mg/kg bw, respectively at 60 min in OGTT even though no activity was observed in the α-glucosidase enzyme inhibitory assay. In an antibacterial assay, the extract's minimum inhibitory concentration (MIC) against E. coli, P. aeruginosa, and S. aureus was determined to be 8, 16, and 8 µg/ml, respectively. This study shows that the usage of A. mollissima leaves in folklore medication is justified.

17.
Nat Commun ; 13(1): 3776, 2022 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-35773283

RESUMEN

In 2016, a 68-year-old patient with a disseminated multidrug-resistant Acinetobacter baumannii infection was successfully treated using lytic bacteriophages. Here we report the genomes of the nine phages used for treatment and three strains of A. baumannii isolated prior to and during treatment. The phages used in the initial treatment are related, T4-like myophages. Analysis of 19 A. baumannii isolates collected before and during phage treatment shows that resistance to the T4-like phages appeared two days following the start of treatment. We generate complete genomic sequences for three A. baumannii strains (TP1, TP2 and TP3) collected before and during treatment, supporting a clonal relationship. Furthermore, we use strain TP1 to select for increased resistance to five of the phages in vitro, and identify mutations that are also found in phage-insensitive isolates TP2 and TP3 (which evolved in vivo during phage treatment). These results support that in vitro investigations can produce results that are relevant to the in vivo environment.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Bacteriófagos , Terapia de Fagos , Infecciones por Acinetobacter/terapia , Acinetobacter baumannii/genética , Anciano , Bacteriófagos/genética , Genómica , Humanos
18.
Molecules ; 27(9)2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35566385

RESUMEN

Cancer is a disorder that rigorously affects the human population worldwide. There is a steady demand for new remedies to both treat and prevent this life-threatening sickness due to toxicities, drug resistance and therapeutic failures in current conventional therapies. Researchers around the world are drawing their attention towards compounds of natural origin. For decades, human beings have been using the flora of the world as a source of cancer chemotherapeutic agents. Currently, clinically approved anticancer compounds are vincristine, vinblastine, taxanes, and podophyllotoxin, all of which come from natural sources. With the triumph of these compounds that have been developed into staple drug products for most cancer therapies, new technologies are now appearing to search for novel biomolecules with anticancer activities. Ellipticine, camptothecin, combretastatin, curcumin, homoharringtonine and others are plant derived bioactive phytocompounds with potential anticancer properties. Researchers have improved the field further through the use of advanced analytical chemistry and computational tools of analysis. The investigation of new strategies for administration such as nanotechnology may enable the development of the phytocompounds as drug products. These technologies have enhanced the anticancer potential of plant-derived drugs with the aim of site-directed drug delivery, enhanced bioavailability, and reduced toxicity. This review discusses mechanistic insights into anticancer compounds of natural origins and their structural activity relationships that make them targets for anticancer treatments.


Asunto(s)
Antineoplásicos , Neoplasias , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Humanos , Neoplasias/tratamiento farmacológico , Plantas , Podofilotoxina/química , Relación Estructura-Actividad
19.
Inflamm Res ; 71(4): 377-396, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35292834

RESUMEN

BACKGROUND: The mayhem COVID-19 that was ushered by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) was declared pandemic by the World Health Organization in March 2020. Since its initial outbreak in late 2019, the virus has affected hundreds of million adults in the world and killing millions in the process. After the approval of newly developed vaccines, severe challenges remain to manufacture and administer them to the adult population globally in quick time. However, we have witnessed several mutations of the virus leading to 'waves' of viral spread and mortality. WHO has categorized these mutations as variants of concern (VOCs) and variants of interest (VOIs). The mortality due to COVID-19 has also been associated with various comorbidities and improper immune response. This has created further complications in understanding the nature of the SARS-CoV2-host interaction that has fuelled doubts in the efficacy of the approved vaccines. Whether there is requirement of booster dose and whether the impending wave could affect the children are some of the hotly debated topics. MATERIALS AND METHODS: A systematic literature review of PubMed, Medline, Scopus, Google Scholar was utilized to understand the nature of Delta variant and how it alters our T-cell responses and cytokine production and neutralizes vaccine-generated antibodies. CONCLUSION: In this review, we discuss the variants of SARS-CoV2 with specific focus on the Delta variant. We also specifically review the T-cell response against the virus and bring a narrative of various factors that may hold the key to fight against this marauding virus.


Asunto(s)
COVID-19 , Vacunas , Adulto , Anticuerpos Antivirales , COVID-19/prevención & control , Vacunas contra la COVID-19 , Niño , Humanos , Pandemias , ARN Viral , SARS-CoV-2 , Linfocitos T
20.
J Nat Med ; 76(2): 490-503, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35032247

RESUMEN

In diabetes, interactions between AGEs (advanced glycation end products) and RAGEs (receptors of AGEs) are responsible for chronic complications and the current work reports the potential of ursolic acid as a RAGE inhibitor. The three-dimensional crystal structure of RAGE was first docked with target molecules by 'AutodockVina' using GROMOS 96 4381 parameters. Druggability and pharmacokinetic properties were calculated from the SwissADME server. In vitro bovine serum albumin (BSA)-glucose fluorescence and BSA-methylglyoxal fluorescence assays were also performed. Finally, alloxan-induced diabetic mice were administered ursolic acid and metformin standards (at 1, 50, 100 mg/kg) for 50 days. Blood glucose levels, several blood parameters, blood lipid profiles, supernatants of homogenized kidney and plasma of mice were examined. In the computational study, ursolic acid showed greater binding affinity (-7.5 kcal/mol) for RAGE with an ADMET profiles and lead-likeness compared to metformin as a standard antidiabetic. In the in vitro fluorescence assays, the IC50 value for ursolic acid was much less than that of metformin standard. During the in vivo study, significant reduction in the levels of blood glucose, HbA1C (glycated hemoglobin), creatinine, uric acid, BUN (blood urea nitrogen), AST (aspartate aminotransferase), ALT (alanine aminotransferase), ALP (alkaline phosphatase) were observed in the ursolic acid and metformin-treated mice. Substantial inhibition of AGEs' formation in the plasma and kidney were also detected. Finally, the histopathological examinations of the kidney revealed reversal of cellular necrosis. Hence, ursolic acid is proved to be a potent AGE inhibitory agent in managing the diabetic complications.


Asunto(s)
Complicaciones de la Diabetes , Diabetes Mellitus Experimental , Triterpenos , Animales , Complicaciones de la Diabetes/tratamiento farmacológico , Diabetes Mellitus Experimental/inducido químicamente , Productos Finales de Glicación Avanzada/metabolismo , Ratones , Receptor para Productos Finales de Glicación Avanzada , Triterpenos/farmacología , Triterpenos/uso terapéutico , Ácido Ursólico
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