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1.
J Extracell Vesicles ; 13(6): e12450, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38859730

RESUMO

Matrix vesicles (MVs) provide the initial site for amorphous hydroxyapatite (HA) formation within mineralizing osteoblasts. Although Na+/Ca2+ exchanger isoform-3 (NCX3, SLC8A3) was presumed to function as major Ca2+ transporter responsible for Ca2+ extrusion out of osteoblast into the calcifying bone matrix, its presence and functional role in MVs have not been investigated. In this study, we investigated the involvement of NCX3 in MV-mediated mineralization process and its impact on bone formation. Using differentiated MC3T3-E1 cells, we demonstrated that NCX3 knockout in these cells resulted in a significant reduction of Ca2+ deposition due to reduced Ca2+ entry within the MVs, leading to impaired mineralization. Consequently, the capacity of MVs to promote extracellular HA formation was diminished. Moreover, primary osteoblast isolated from NCX3 deficient mice (NCX3-/-) exhibits reduced mineralization efficacy without any effect on osteoclast activity. To validate this in vitro finding, µCT analysis revealed a substantial decrease in trabecular bone mineral density in both genders of NCX3-/- mice, thus supporting the critical role of NCX3 in facilitating Ca2+ uptake into the MVs to initiate osteoblast-mediated mineralization. NCX3 expression was also found to be the target of downregulation by inflammatory mediators in vitro and in vivo. This newfound understanding of NCX3's functional role in MVs opens new avenues for therapeutic interventions aimed at enhancing bone mineralization and treating mineralization-related disorders.


Assuntos
Calcificação Fisiológica , Cálcio , Camundongos Knockout , Osteoblastos , Trocador de Sódio e Cálcio , Animais , Osteoblastos/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Camundongos , Cálcio/metabolismo , Masculino , Osteogênese , Diferenciação Celular , Feminino , Vesículas Extracelulares/metabolismo , Linhagem Celular
2.
Fitoterapia ; 176: 105977, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38697228

RESUMO

The genus Bistorta comprises about 43 accepted species that are widely used by local people and medicinal practitioners for the treatment of rheumatism, tuberculosis, inflammation, respiratory infection, and other diseases. The objective of this review is to present up-to-date information from the scientific literature about the phytochemistry, pharmacology, and toxicology of Bistorta. At present, there is a lack of a comprehensive review that consolidates the various scientific studies conducted on the genus Bistorta. To address this knowledge gap, a global review has been compiled on the genus Bistorta, which emphasizes ethnomedicinal uses, phytochemistry, and pharmacology. To gather information about Bistorta, relevant keywords were used to search internet databases including Google scholar, PubMed, ResearchGate, Web of Science, Europe PMC, CNKI, and Wiley Online Library. Additionally, published books that provided an overview of existing literature studies were consulted for reference purposes. Chemical structures and formulas of compounds were verified using the PubChem database and drawn using Chem Draw Ultra 6.0. The scientific nomenclature utilized in this review follows The World Flora Online and The Plant of the World Online (PoWo). A comprehensive evaluation of literature sources revealed that the genus Bistorta has been recognized for its ethnomedical properties and has been used in traditional healthcare for several millennia. Chemical analysis has identified various compounds such as phenolics, flavonoids saponins, terpenes, sterols, and coumarins which have been shown to have significant pharmacological effects such as anti-tumor, anti-inflammatory, anti-oxidant anti-rheumatic and anti-microbial properties. The pharmacological research has only partially validated the traditional and local uses of Bistorta species. Further research is required to investigate the mechanisms of the plant's active compounds, as well as its potential therapeutic applications in treating conditions like diabetes and neurodegenerative diseases. Additionally, there is no clinical evidence to provide the health benefits of these plants. To confirm the pharmacological activities, clinical efficacy, and non-toxicity of Bistorta species, more comprehensive and systematic preclinical studies, and clinical trials are needed.


Assuntos
Medicina Tradicional , Compostos Fitoquímicos , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Humanos , Estrutura Molecular , Fitoterapia , Plantas Medicinais/química , Etnofarmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Animais
3.
Environ Monit Assess ; 196(5): 472, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662176

RESUMO

Endemic medicinal plants deserve immediate research priorities as they typically show a limited distribution range, represent few and fragmented populations in the wild and are currently facing anthropogenic threats like overharvesting and habitat degradation. One of the important aspects of ensuring their successful conservation and sustainable utilization lies in comprehending the fundamental seed biology, particularly the dormancy status and seed germination requirements of these plants. Here, we studied the seed eco-physiology and regeneration potential of Swertia thomsonii-an endemic medicinal plant of western Himalaya. We investigated the effect of different pre-sowing treatments, sowing media and sowing depth on seed germination parameters of S. thomsonii. Seeds of S. thomsonii exhibit morphophysiological dormancy (MPD), i.e. when the embryo of the seed is morphologically and/or physiologically immature. Wet stratification at 4 °C for 20 days, pre-sowing treatment with 50 ppm GA3 and pre-sowing treatment with 50 ppm KNO3 were found ideal for overcoming dormancy and enhancing the seed germination of S. thomsonii. Furthermore, seed germination and seedling survival were significantly influenced by pre-sowing treatments, sowing media and sowing depth. The percentage of seed germination and seedling survival got enhanced up to 84-86% and 73-75% respectively when seeds were pre-treated with GA3 or KNO3 and then sown in cocopeat + perlite (1:1) at a depth of 1 cm. The information obtained in the present study outlines an efficient protocol for large-scale cultivation of S. thomsonii thereby limiting the pressure of overexploitation from its natural habitats and may also help in the restoration and conservation of this valuable plant species.


Assuntos
Conservação dos Recursos Naturais , Germinação , Plantas Medicinais , Sementes , Swertia , Plantas Medicinais/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Conservação dos Recursos Naturais/métodos , Swertia/fisiologia , Índia , Plântula/crescimento & desenvolvimento , Ecossistema , Dormência de Plantas
4.
In Silico Pharmacol ; 12(1): 14, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38419919

RESUMO

Prevention from disease is presently the cornerstone of the fight against COVID-19. With the rapid emergence of novel SARS-CoV-2 variants, there is an urgent need for novel or repurposed agents to strengthen and fortify the immune system. Existing vaccines induce several systemic and local side-effects that can lead to severe consequences. Moreover, elevated cytokines in COVID-19 patients with cancer as co-morbidity represent a significant bottleneck in disease prognosis and therapy. Withania somnifera (WS) and its phytoconstituent(s) have immense untapped immunomodulatory and therapeutic potential and the anticancer potential of WS is well documented. To this effect, WS methanolic extract (WSME) was characterized using HPLC. Withanolides were identified as the major phytoconstituents. In vitro cytotoxicity of WSME was determined against human breast MDA-MB-231 and normal Vero cells using MTT assay. WSME displayed potent cytotoxicity against MDA-MB-231 cells (IC50: 66 µg/mL) and no effect on Vero cells in the above range. MD simulations of Withanolide A with SARS-CoV-2 main protease and spike receptor-binding domain as well as Withanolide B with SARS-CoV spike glycoprotein and SARS-CoV-2 papain-like protease were performed using Schrödinger. Stability of complexes followed the order 6M0J-Withanolide A > 6W9C-Withnaolide B > 5WRG-Withanolide B > 6LU7-Withanolide A. Maximum stable interaction(s) were observed between Withanolides A and B with SARS-CoV-2 and SARS-CoV spike glycoproteins, respectively. Withanolides A and B also displayed potent binding to pro-inflammatory markers viz. serum ferritin and IL-6. Thus, WS phytoconstituents have the potential to be tested further in vitro and in vivo as novel antiviral agents against COVID-19 patients having cancer as a co-morbidity. Supplementary Information: The online version contains supplementary material available at 10.1007/s40203-023-00184-y.

5.
Environ Monit Assess ; 196(3): 241, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38324063

RESUMO

Phytochemicals are broadly acknowledged for their health-promoting effects owing to the fact of their capacity to counteract free radicals (e.g., superoxide anion radical, hydroxyl radical, hydroperoxyl radical, singlet oxygen, hypochlorite, and nitric oxide) and shield against oxidative stress induced by environmental factors. This study aimed to investigate the relationship between altitude, morphology, soil parameters, in vitro antioxidant potential and phytochemical composition of Phlomis cashmeriana collected from four different locations of Kashmir Himalaya characterized by diverse habitats and elevations. Various factors, such as extraction method, solvent polarity, and habitat conditions, can impact the quantity and efficacy of phytochemicals in plants. The aim of current study was to analyze phytochemical composition and antioxidant activity of P. cashmeriana, an important medicinal plant found in the Kashmir Himalaya region. The antioxidant activity was accessed using several assays and the plant populations were selected based on their diverse habitat features and altitudes. HR-LCMS was conducted for both below-ground and above-ground parts. Some important compounds such as, catechin, vinainsenoside, acutilobin, and kaempferol were reported for the first time from P. cashmeriana. Results showed that methanol was the most efficient solvent for extracting phytochemicals. During the current study, it was also found that the below-ground parts exhibited superior antioxidant activity compared to the above-ground parts. Notably, Site IV demonstrated the highest antioxidant potential; a positive correlation between altitude and antioxidant activity was also found. In conclusion, present research identified specific elite populations having highest antioxidant potential and are well-suited for large-scale cultivation of P. cashmeriana.


Assuntos
Antioxidantes , Phlomis , Himalaia , Monitoramento Ambiental , Compostos Fitoquímicos , Solventes
6.
Cell Rep Med ; 5(1): 101360, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38232694

RESUMO

The failure of the Staphylococcus aureus (SA) IsdB vaccine trial can be explained by the recall of non-protective immune imprints from prior SA exposure. Here, we investigate natural human SA humoral imprints to understand their broader impact on SA immunizations. We show that antibody responses against SA cell-wall-associated antigens (CWAs) are non-opsonic, while antibodies against SA toxins are neutralizing. Importantly, the protective characteristics of the antibody imprints accurately predict the failure of corresponding vaccines against CWAs and support vaccination against toxins. In passive immunization platforms, natural anti-SA human antibodies reduce the efficacy of the human monoclonal antibodies suvratoxumab and tefibazumab, consistent with the results of their respective clinical trials. Strikingly, in the absence of specific humoral memory responses, active immunizations are efficacious in both naive and SA-experienced mice. Overall, our study points to a practical and predictive approach to evaluate and develop SA vaccines based on pre-existing humoral imprint characteristics.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Vacinas Antiestafilocócicas , Vacinas , Animais , Humanos , Camundongos , Imunização , Staphylococcus aureus , Ensaios Clínicos como Assunto
8.
Nat Prod Res ; 38(4): 563-580, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38285923

RESUMO

Phytochemicals have become significantly important for scientific research since these possess incredibly remarkable health benefits, especially antioxidant potential to scavenge free radicals and combat the harmful effects of oxidative stress caused by adverse environmental factors. The efficacy and quantity of these phytochemicals relies upon numerous factors including the extraction method, solvent polarity and the habitat features in which the plant is growing. In this study we emphasized on phytochemical analysis and antioxidant activity of Bistorta amplexicaulis, an important medicinal plant species from Kashmir Himalaya. We evaluated antioxidant activity using different assays from all the selected sites to enumerate the impact of habitat. The sites were selected based on varying habitat features and altitude. Our results revealed that Ethyl acetate is the potent solvent for the extraction of phytochemicals. Below ground parts exhibited better scavenging activity than the above ground parts. Amongst the sites, we found the maximum antioxidant potential at Site I. A positive correlation was found between antioxidant activity and altitude while soil attributes (OC, OM, N, P, and K) and most of the morphological traits showed a negative correlation. Overall, our study identified the elite populations that could be utilized for mass propagation and harness the ultimate antioxidant potential of B. amplexicaulis.


Assuntos
Antioxidantes , Extratos Vegetais , Antioxidantes/farmacologia , Antioxidantes/análise , Extratos Vegetais/farmacologia , Extratos Vegetais/análise , Altitude , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/análise , Ecossistema , Solventes
9.
ANZ J Surg ; 94(5): 931-937, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38156719

RESUMO

BACKGROUND: A positive circumferential resection margin (CRM) after rectal cancer surgery, which can be the result of direct or indirect tumour involvement, has consistently been associated with increased local recurrence and poorer survival. However, little is known of the differential impact of the mode of tumour involvement on outcomes. METHODS: 1460 consecutive patients undergoing rectal cancer resection between 2003 and 2018 were retrospectively assessed. Histopathology reports for patients with a positive CRM were reviewed to determine cases of direct (R1-tumour) or indirect tumour involvement (R1-other). Disease-free survival (DFS) and overall survival (OS) were assessed by Kaplan-Meier analysis. The role of the mode of CRM positivity was examined by univariate and multivariate Cox proportional hazards models. RESULTS: Eighty-five patients had an R1 resection due to CRM involvement (5.8%). Of those, 69 were due to direct tumour involvement, while 16 were from indirect causes. Kaplan-Meier analysis revealed that R1-other was associated with increased OS (hazard ratio 0.40, log-rank P = 0.006) and DFS (P = 0.043). Multivariate regression confirmed that the mode of CRM positivity was an independent predictor of OS. More interestingly, the patterns of recurrence were different between the two groups, with R1-tumour leading to significantly more local recurrence (P = 0.04). CONCLUSIONS: Our data strongly suggests that direct tumour involvement of the CRM confers worse prognosis after rectal cancer surgery. Importantly, differences in the site and frequency of recurrences make a case for better stratification of patients with a positive CRM to guide treatment decisions.


Assuntos
Margens de Excisão , Recidiva Local de Neoplasia , Neoplasias Retais , Humanos , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia , Neoplasias Retais/mortalidade , Masculino , Feminino , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Intervalo Livre de Doença , Estimativa de Kaplan-Meier , Taxa de Sobrevida
10.
Nat Commun ; 14(1): 8061, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052825

RESUMO

Acne is a dermatologic disease with a strong pathologic association with human commensal Cutibacterium acnes. Conspicuously, certain C. acnes phylotypes are associated with acne, whereas others are associated with healthy skin. Here we investigate if the evolution of a C. acnes enzyme contributes to health or acne. Two hyaluronidase variants exclusively expressed by C. acnes strains, HylA and HylB, demonstrate remarkable clinical correlation with acne or health. We show that HylA is strongly pro-inflammatory, and HylB is modestly anti-inflammatory in a murine (female) acne model. Structural and phylogenic studies suggest that the enzymes evolved from a common hyaluronidase that acquired distinct enzymatic activity. Health-associated HylB degrades hyaluronic acid (HA) exclusively to HA disaccharides leading to reduced inflammation, whereas HylA generates large-sized HA fragments that drive robust TLR2-dependent pathology. Replacing an amino acid, Serine to Glycine near the HylA catalytic site enhances the enzymatic activity of HylA and produces an HA degradation pattern intermediate to HylA and HylB. Selective targeting of HylA using peptide vaccine or inhibitors alleviates acne pathology. We suggest that the functional divergence of HylA and HylB is a major driving force behind C. acnes health- and acne- phenotype and propose targeting of HylA as an approach for acne therapy.


Assuntos
Acne Vulgar , Hialuronoglucosaminidase , Humanos , Feminino , Animais , Camundongos , Pele/microbiologia , Propionibacterium acnes/genética , Aminoácidos
11.
Environ Monit Assess ; 196(1): 60, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38110625

RESUMO

Studying functional trait diversity can provide crucial clues about the adaptive survival strategies of regional plant species pool. Despite large-scale trait datasets available worldwide, the plant trait data from many biodiversity hotpot regions, like the Himalaya is still scarce. In this study, we aimed to investigate the plant functional traits and aboveground biomass of understory herbaceous vegetation in temperate forests of Overa-Aru wildlife sanctuary of Kashmir Himalaya. We also investigate how these functional traits correlate and what is the magnitude of trait-biomass relationship across the herbaceous species pool. For this, we conducted field sampling and measured leaf functional traits and aboveground biomass of 38 plant species in the study region during peak growing season (July-August) in the year 2021. The results revealed a significant interspecific trait variability among the species studied. We observed a high variability in leaf size and type spectra of the species, with nanophyll and simple leaf lamina, respectively, the most common types among the species studied. The correlation analysis revealed that plant height was positively correlated with aboveground biomass. The variation partitioning analysis revealed that the plant height explained the maximum fraction of variation in aboveground biomass, while least by specific leaf area. Overall, the findings from the present study provide useful insights in understanding trait-trait relationship and trait-environment interaction at the regional scale and can also help in recognizing adaptive functional traits of plant species that determine plant survival under the changing climate in this Himalayan region.


Assuntos
Monitoramento Ambiental , Florestas , Biomassa , Himalaia , Biodiversidade , Plantas
12.
Front Cardiovasc Med ; 10: 1223954, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38099220

RESUMO

Assessing regional wall motion abnormalities (RWMA) in the myocardium may provide early diagnosis and treat chronic remodeling in STEMI patients. We assessed RWMA in 217 subjects with anterior STEMI admitted to Era University Hospital in Lucknow, UP, India. Besides abnormalities in the LAD territory, sub-sets of patients exhibited diffuse regional myocardial dysfunction. Interestingly, variations in serum electrolytes, specifically sodium and potassium, significantly affected the distribution and frequency of RWMA. Notably, RWMA occurred in the basal septum, apical septum, apex, and lateral wall in the anterior STEMI group. Additionally, the rate of regional dysfunction varied with serum urea and creatinine levels. This suggests that anterior STEMI can manifest myocardial abnormalities beyond the LAD territory. These findings indicate that ST-segment elevation might not be specific, possibly influenced by electrolyte changes affecting cardiac rhythm. Therefore, diagnosing and correcting region-specific wall motion abnormalities and electrolyte imbalances may improve outcomes in STEMI patients.

13.
Environ Monit Assess ; 195(9): 1117, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37648899

RESUMO

In the Himalaya, collection of fodder from protected areas by local communities for sustenance of their livestock is an integral part of mountain farming systems. Here, we assess the diversity and utilization patterns of fodder resources collected by local communities from Overa-Aru wildlife sanctuary in Kashmir Himalaya. A multi-stage random sampling was employed to select sample villages (5) and households (81) for the survey. Data were collected through personal interviews of household heads administering an interview schedule and then analyzed using descriptive statistics and linear regression model. The results revealed that 74 fodder species were collected by the local communities from the sanctuary. The diversity and magnitude of fodder resource utilization varied across the study area. The fodder collection and utilization on per day and annual basis ranged from 25 to 90 and 2760 to 13,770 kg/household, respectively. Across the surveyed villages, the fodder was mainly collected by the females (60%). A positive but non-significant relationship was found between the number of persons collecting fodder and quantity of fodder collection/household/day, while a positive and significant relationship was found between the herd size and quantity of fodder collection/household/day. We also found a negative but non-significant relationship between the education status of respondents and the number of livestock holding. Based on our findings, we suggest policy and management interventions such as regulating livestock grazing, promoting plantation of frequently collected fodder species, and better use of agriculture byproducts to guide the sustainable management of fodder resources in this Himalayan protected area, with learning for elsewhere.


Assuntos
Agricultura , Monitoramento Ambiental , Feminino , Animais , Ração Animal , Animais Selvagens , Fazendas , Gado
14.
Planta Med ; 89(12): 1147-1164, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37380043

RESUMO

The ethnic communities living near protected areas are critically dependent on medicinal plants for their healthcare. Although several ethnomedicinal studies are available from the Himalaya, quantitative studies focusing on protected areas in this region are largely overlooked. In this study, we aimed to document the ethnomedicinal plants of the Overa-Aru wildlife sanctuary in Kashmir Himalaya. We conducted a systematic field survey in the study area during 2020 - 2021 to collect primary data from 110 participants through semi-structured interviews and questionnaires. The data was analyzed using quantitative indices and Pearson's correlation. We recorded 64 plant species used against 8 human disease categories, including some first-time reports from the region. Asteraceae and Lamiaceae were the most dominant families and herbs were the dominant growth form. The most common plant part used were leaves, and the main method of preparation was decoction. Plant species with the highest relative frequency of citation was Achillea millifolium (0.83). Informant consensus factor for each disease category ranged from 0.94 to 0.97. We found a strong positive correlation between participants' age and citations (r = 0.85), but a negative correlation between the participants' education status and citations (r = - 0.11). Our results revealed that the younger generation possesses the least ethnomedicinal information. We recommend that the species with high use values and fidelity level merit priority in phytochemical and pharmaceutical studies. Our findings highlight that protected areas, besides their prime importance in biodiversity conservation, play a pivotal role in providing the healthcare provisioning ecosystem services to the ethnic communities.


Assuntos
Animais Selvagens , Plantas Medicinais , Animais , Humanos , Etnobotânica/métodos , Ecossistema , Medicina Tradicional/métodos , Inquéritos e Questionários , Fitoterapia
16.
Cureus ; 14(6): e25943, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35844344

RESUMO

Background Glaucoma is one of the most common eye diseases in the elderly and the major cause of irreversible vision loss worldwide. Adherence to life-long therapies is crucial to prevent glaucoma progression. The current study aims to assess the educational element and its impact on glaucoma medication compliance over short and long periods. Methods This was a survey-based, prospective, interventional study, conducted via interviews of all glaucoma patients presented to the Ophthalmology Center at King Abdullah Medical City (KAMC), Makkah, Saudi Arabia. To achieve the study's aim, a questionnaire with 31 items was utilized, followed by a structured program between September 2019 to June 2021. After that, a second questionnaire was used after a one month to one year to re-evaluate the intervention. Data was automatically collected in Microsoft Excel (Microsoft Corporation, Redmond, Washington, United States) and entered into IBM SPSS Statistics for Windows, Version 22.0 (Released 2013; IBM Corp., Armonk, New York, United States) for analysis. Results Non-compliance was detected in 15.7% of all recruited patients (n=134). However, the non-compliance percentage dropped to 10 (7.5%) after the structured program (P=0.028). Contributing factors were low educational level, bilateral eye disease, duration of treatment more than two years, and having more than two eye treatment bottles; however, the P-value was insignificant. Conclusions About one-sixth of our glaucoma patients were found to be non-compliant. However, the non-compliance reduced by more than half after the structured educational program. Treatment adherence can be improved by implementing awareness and correcting the beliefs about illness and medicines, thus potentially delaying disease development.

17.
Cell Host Microbe ; 30(8): 1163-1172.e6, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35803276

RESUMO

Humans frequently encounter Staphylococcus aureus (SA) throughout life. Animal studies have yielded SA candidate vaccines, yet all human SA vaccine trials have failed. One notable vaccine "failure" targeted IsdB, critical for host iron acquisition. We explored a fundamental difference between humans and laboratory animals-natural SA exposure. Recapitulating the failed phase III IsdB vaccine trial, mice previously infected with SA do not mount protective antibody responses to vaccination, unlike naive animals. Non-protective antibodies exhibit increased α2,3 sialylation that blunts opsonophagocytosis and preferentially targets a non-protective IsdB domain. IsdB vaccination of SA-infected mice recalls non-neutralizing humoral responses, further reducing vaccine efficacy through direct antibody competition. IsdB vaccine interference was overcome by immunization against the IsdB heme-binding domain. Purified human IsdB-specific antibodies also blunt IsdB passive immunization, and additional SA vaccines are susceptible to SA pre-exposure. Thus, failed anti-SA immunization trials could be explained by non-protective imprint from prior host-SA interaction.


Assuntos
Proteínas de Transporte de Cátions , Infecções Estafilocócicas , Vacinas , Animais , Humanos , Camundongos , Fagocitose , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus
18.
Cell Chem Biol ; 29(5): 730-740, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35594849

RESUMO

Staphylococcus aureus (SA) is a leading cause of bacterial infection and antibiotic resistance globally. Therefore, development of an effective vaccine has been a major goal of the SA field for the past decades. With the wealth of understanding of pathogenesis, the failure of all SA vaccine trials has been a surprise. We argue that experimental SA vaccines have not worked because vaccines have been studied in naive laboratory animals, whereas clinical vaccine efficacy is tested in immune environments reprogrammed by SA. Here, we review the failed SA vaccines that have seemingly defied all principles of vaccinology. We describe major SA evasion strategies and suggest that they reshape the immune environment in a way that makes vaccines prone to failures. We propose that appropriate integration of concepts of host-pathogen interaction into vaccine study designs could lead to insight critical for the development of an effective SA vaccine.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Vacinas , Animais , Interações Hospedeiro-Patógeno , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus
19.
Vasc Endovascular Surg ; 56(2): 212-215, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34663143

RESUMO

Bronchial artery (BA) pseudoaneurysm is an uncommon vascular complication of tuberculosis (TB), and early diagnosis is crucial due to risk of rupture and life-threatening hemorrhage. Immediate intervention is warranted in massive hemoptysis due to high mortality. Various causes of massive hemoptysis are TB, bronchiectasis, aspergilloma, lung abscess, lung cancer, necrotizing pneumonia, and cystic fibrosis. Active pulmonary TB as well as chronic pulmonary TB can manifest with massive hemoptysis. Hemoptysis in active TB occurs due to ulceration in bronchiolar wall, eroding the wall of the adjacent BA or pulmonary artery, and in chronic TB due to hypertrophied bronchial arteries, or bronchiectasis, or aspergilloma. Herein, we report a case of pulmonary TB causing intrapulmonary BA pseudoaneurysm in a young male patient who presented with acute massive hemoptysis. The BA pseudoaneurysm as well as other hypertrophied bronchial arteries were embolized using polyvinyl alcohol (PVA) particles.


Assuntos
Falso Aneurisma , Embolização Terapêutica , Tuberculose , Falso Aneurisma/diagnóstico por imagem , Falso Aneurisma/etiologia , Falso Aneurisma/terapia , Artérias Brônquicas/diagnóstico por imagem , Hemoptise/etiologia , Hemoptise/terapia , Humanos , Masculino , Recidiva Local de Neoplasia , Resultado do Tratamento
20.
Nanotechnology ; 32(46)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34340224

RESUMO

Development of eco-friendly synthetic methods has resulted in the production of biocompatible Ag NPs for applications in medical sector. To overcome the prevailing antibiotic resistance in bacteria, Ag NPs are being extensively researched over the past few years due to their broad spectrum and robust antimicrobial properties. Silver nanoparticles are also being studied widely in advanced anticancer therapy as an alternative anticancer agent to combat cancer in an effective manner. Keeping this backdrop in consideration, this review aims to provide an extensive coverage of the recent progresses in the green synthesis of Ag NPs specifically using plant derived reducing agents such phytochemicals and numerous other biopolymers. Current development in antimicrobial activity of Ag NPs against various pathogens has been deliberated at length. Recent advances in potent anticancer activity of the biogenic Ag NPs against various cancerous cell lines has also been discussed in detail. Mechanistic details of the synthesis of Ag NPs, their anticancer and antimicrobial action has also been highlighted.


Assuntos
Anti-Infecciosos/química , Antineoplásicos/química , Nanopartículas Metálicas/química , Compostos Fitoquímicos/química , Polímeros/química , Prata/química
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