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1.
Chempluschem ; 89(7): e202300572, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38340361

RESUMO

Light aromatics (benzene, toluene, and xylene, collectively known as BTX) are essential commodity chemicals in the petrochemical industry. The present study examines the aromatization of bioethanol with Cr- and Ga-modified ZSM-5. Both Cr and Ga were incorporated by the ion-exchange method. Cr-modified ZSM-5 outperforms the Ga-modified ZSM-5 and H-ZSM-5 catalysts. Cr-H-ZSM-5 almost doubled the carbon yield of aromatics compared to H-ZSM-5 at an optimum reaction temperature of 450 °C. Cr-H-ZSM-5 produced aromatics with a yield of ~40 %. The effect of dilution in feed on BTX production is also studied. Cr-H-ZSM-5 was found to be more active than H-ZSM-5. Complete ethanol conversion was obtained with both pure and dilute bioethanol. The Bronsted-Lewis acid (BLA) pair formed after metal incorporation is responsible for dehydrogenation followed by aromatization, leading to increased aromatic production.

2.
Indian J Ophthalmol ; 72(2): 185-189, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38099354

RESUMO

PURPOSE: To evaluate the association between meibomian gland dysfunction (MGD) and primary chronic dacryocystitis (PCD) and the effect of dacryocystorhinostomy (DCR) on tear film stability and MGD. METHODS: This prospective, interventional, non-randomized study involved 50 unilateral acquired PCD cases and 50 age-matched healthy controls. Patients with lid abnormalities, ocular trauma, previous ocular surgery, contact lens wearers, and chronic topical or systemic drug users were excluded from the study. After a detailed history, the ocular surface disease index (OSDI) was calculated. The ocular assessment included visual acuity, tear meniscus height (TMH), tear break-up time (TBUT), tear well diameter (TWD), Schirmer 1 test, meibomian gland (MG) expressibility, and meibography. PCD eyes underwent external DCR, and the tests were repeated after 8 weeks. RESULTS: The mean age of PCD cases was 42.58 ± 12.74 years, the male: female ratio was 7:19, and the mean duration of epiphora was 2.2 ± 1 years. The MG expressibility grade of ≥2 was seen in 98% (49/50) PCD eyes, which was strongly associated with PCD as compared to controls (OR = 563, P = 0.00, 95% CI = 60.71-5229.70). MG loss ≥50% was seen in 62% (31/50) of PCD eyes and none of the control eyes. Following DCR, MG loss remained unchanged, and a significant decrease occurred in OSDI scores, TWD and Schirmer 1 values, and MG expressibility grade (Z = -6.85). The mean TMH decreased from 767.60 ± 331.60 µm to 384 ± 204.29 µm ( P = 0.004) post DCR. CONCLUSIONS: PCD is strongly associated with MGD. DCR reverses the functional MG changes with improvement in the tear film stability but no effect on MG loss.


Assuntos
Dacriocistite , Síndromes do Olho Seco , Doenças Palpebrais , Disfunção da Glândula Tarsal , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Doenças Palpebrais/diagnóstico , Doenças Palpebrais/etiologia , Estudos Prospectivos , Glândulas Tarsais/diagnóstico por imagem , Dacriocistite/complicações , Dacriocistite/diagnóstico , Lágrimas
3.
Nanotheranostics ; 7(4): 412-423, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37650012

RESUMO

Antimicrobial polymers (AMP) appear to be a promising candidate to deal with the current scenario of bacterial resistance against conventional drugs and antibiotics as they mainly depend on disrupting the bacterial membrane. This work investigates the effect of polycations bearing aromatic and aliphatic pendant cationic groups on the antimicrobial performance of AMP. A radical polymerization strategy was adopted to synthesize two different copolymers and convert them into polycations upon post-modification. Polyelectrolytes were converted into nanoparticles by nanoprecipitation and named PE1 and PE2. Polymers were analyzed by NMR, FT-IR, and gel permeation chromatography (GPC). PE1 and PE2 nanoparticles were uniform, spherical particles from FESEM, size, and zeta potential measurements. The antimicrobial properties of polyelectrolytes were determined against pathogenic Escherichia coli (E. coli), Bacillus Subtilis (B. Subtilis), Bacillus Amyloliquefaciens (B. Amyloliquefaciens) and Citrobecter Freundii (C. Freundii) bacterias. The biocidal activity determination studies showed that polyelectrolyte PE2 with aromatic pendant units outperformed PE1 with the aliphatic pendant group. This work highlights the remarkable effect of aromatic segmentation, which provides microbial inhibition, and killing is demonstrated as an antibacterial surface coating.


Assuntos
Escherichia coli , Nanopartículas , Polieletrólitos , Espectroscopia de Infravermelho com Transformada de Fourier , Polímeros , Antibacterianos/farmacologia
4.
Curr Drug Deliv ; 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37519200

RESUMO

When breast cells divide and multiply out of control, it is called breast cancer. Symptoms include lump formation in the breast, a change in the texture or color of the breast, or a discharge from the nipple. Local or systemic therapy is frequently used to treat breast cancer. Surgical and radiation procedures limited to the affected area are examples of local management. There has been significant worldwide progress in the development of monoclonal antibodies (mAbs) since 1986, when the first therapeutic mAb, Orthoclone OKT3, became commercially available. mAbs can resist the expansion of cancer cells by inducing the destruction of cellular membranes, blocking immune system inhibitors, and preventing the formation of new blood vessels. mAbs can also target growth factor receptors. Understanding the molecular pathways involved in tumor growth and its microenvironment is crucial for developing effective targeted cancer therapeutics. Due to their unique properties, mAbs have a wide range of clinical applications. Antibody-drug conjugates (ADCs) are drugs that improve the therapeutic index by combining an antigen-specific antibody with a payload. This review focuses on the therapeutic applications, mechanistic insights, characteristics, safety aspects, and adverse events of mAbs like trastuzumab, bevacizumab, pertuzumab, ertumaxomab, and atezolizumab in breast cancer treatment. The creation of novel technologies utilizing modified antibodies, such as fragments, conjugates, and multispecific antibodies, must be a central focus of future studies. This review will help scientists working on developing mAbs to treat cancers more effectively.

5.
Int J Surg ; 109(8): 2365-2377, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37158143

RESUMO

Wounds represent various significant health concerns for patients and also contribute major costs to healthcare systems. Wound healing comprises of overlapped and various coordinated steps such as homeostasis, inflammation, proliferation, and remodeling. In response to the failure of many strategies in delivering intended results including wound closure, fluid loss control, and exhibiting properties such as durability, targeted delivery, accelerated action, along with histocompatibility, numerous nanotechnological advances have been introduced. To understand the magnitude of wound therapy, this systematic and updated review discussing the effectiveness of nanoemulsions has been undertaken. This review portrays mechanisms associated with wound healing, factors for delayed wound healing, and various technologies utilized to treat wounds effectively. While many strategies are available, nanoemulsions have attracted the tremendous attention of scientists globally for the research in wound therapy due to their long-term thermodynamic stability and bioavailability. Nanoemulsions not only aid in tissue repair, but are also considered as an excellent delivery system for various synthetic and natural actives. Nanotechnology provides several pivotal benefits in wound healing, including improved skin permeation, controlled release, and stimulation of fibroblast cell proliferation. The significant role of nanoemulsions in improved wound healing along with their preparation techniques has also been highlighted with special emphasis on mechanistic insights. This article illustrates recent research advancements for the utilization of nanoemulsions in wound treatment. An adequate literature search has been conducted using the keywords 'Nanoemulsions in wound healing', 'Wound therapy and nanoemulsions', 'Herbal actives in wound therapy', 'Natural oils and wounds treatment' etc., from PubMed, Science Direct, and Google Scholar databases. Referred and original publications in the English language accessed till April 2022 has been included, whereas nonEnglish language papers, unpublished data, and nonoriginal papers were excluded from the study.


Assuntos
Atenção à Saúde , Cicatrização , Humanos
6.
Sci Rep ; 12(1): 16978, 2022 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-36216852

RESUMO

Floods are the most commonly occurring natural disasters in India due to India's unique geographical location and socioeconomic conditions. Frequent flooding causes enormous loss of human lives and damage crops and public utilities. Furthermore, floods adversely affect economic development and increase the government's financial burden by increasing spending on various disaster mitigation measures. Recent empirical literature based on cross-national comparisons shows that disaster fatalities and damages are monotonically decreasing in per capita income. We challenge this view on the monotonic negative relationship between income and flood damages. We examine the non-monotonic (inverted U-shaped) relationship between per capita income and flood impact in terms of deaths, people affected, and damages due to floods in 19 major Indian states from 1980 to 2011, using Poisson and Tobit estimation methods. In particular, deaths and the population affected by floods increase with a turning point of income up to 882 US$ and 578 US$, respectively, and diminishes thereafter. Our results confirm an inverted U-shaped relationship between income and fatalities and the population affected by floods. In addition to income, we argue that government responsiveness plays an essential role in mitigating the risk of floods. We employ the fixed-effect Poisson estimation method to examine the government's role in protecting people against disaster risk, focusing on regional differences in India. Deaths from floods remain non-linear and follow the inverted U-pattern with respect to government responsiveness. However, the effect of government responsiveness on flood fatalities and flood damages is statistically insignificant. Our results further suggest that high-income states experience a lower death toll from floods. The high-income (rich) states are capable of incurring a higher threshold level of income and higher natural calamity expenditure to reduce flood fatalities and protect the population affected by floods than the low-income (poor) states. The poor states have minimal resources and face severe financial constraints to reduce the death toll from floods. From the perspective of public policy, the poor states, in particular, require an increase in income, better governance, and effective disaster management policies to mitigate flood impact.


Assuntos
Desastres , Desastres Naturais , Inundações , Governo , Humanos , Renda
7.
J Lab Physicians ; 14(1): 84-86, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36186262

RESUMO

Lymphoepithelioma-like carcinoma of the urinary bladder is a rare variant of urothelial carcinoma that was first described by Zukerberg in 1991 and confirmed as a type of urothelial carcinoma by the WHO classification of the urinary system tumors. A 63-year-old man presented with the chief complaint of gross hematuria for 2 months. Sections from transurethral resection of the bladder revealed urothelial carcinoma. A radical cystoprostatectomy was performed and a final histopathological examination revealed high-grade muscle-invasive urothelial carcinoma, lymphoepithelial variant. The patient has been receiving adjuvant chemotherapy with no recurrence reported to date. This is the third case reported in India to date to the best of our knowledge. Owing to its rare presentation, no definite treatment guidelines have been established for this entity. Various studies from the English literature suggest a conservative approach.

8.
Indian J Ophthalmol ; 70(11): 3858-3863, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36308113

RESUMO

Purpose: To study the effect of wound size modulation on pre-existing astigmatism by on-axis placement of incision in manual small-incision cataract surgery (MSICS). Methods: In this prospective interventional study conducted at a tertiary care centre, 40 eyes of 40 consecutive senile cataract patients with 1.00-3.00 D corneal astigmatism were enrolled for the study. MSICS by modified Blumenthal's technique was performed through 6.0, 6.5, and 7.0 mm on-axis incision in 1.0-1.49 D (group A), 1.50-1.99 D (group B), and 2.00-3.00 D (group C) astigmatism, respectively. Surgically induced astigmatism (SIA) was calculated by vector analysis and double angle plots (DAP) at 12 weeks postoperatively. Results: There were 22 males and 18 females with mean age of 58.12 ± 1.18 years. The mean SIA at 12 weeks was 0.85 ± 0.28 D in group A (17 eyes), 1.32 ± 0.65 D in group B (10 eyes), and 1.91 ± 0.69 D in group C (13 eyes). The overall median uncorrected visual acuity was 0.18 (IQR = 0 to 0.2). The mean astigmatism decreased from 1.95 ± 0.74 D to 1.04 + 0.57 D (P = 0.00) in superior incision and from 1.70 + 0.50 D to 0.92 ± 0.45 D (P = 0.00) in temporal incision group with central shift of centroid in all cases. Conclusion: The customization of on-axis external incision size can be used to manage pre-existing corneal astigmatism of less than 3.00 D using both temporal and superior incisions effectively.

9.
Conserv Biol ; 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35288989

RESUMO

As ecological data and associated analyses become more widely available, synthesizing results for effective communication with stakeholders is essential. In the case of wildlife corridors, managers in human-dominated landscapes need to identify both the locations of corridors and multiple stakeholders for effective oversight. We synthesized 5 independent studies of tiger (Panthera tigris) connectivity in central India, a global priority landscape for tiger conservation, to quantify agreement on landscape permeability for tiger movement and potential movement pathways. We used the latter analysis to identify connectivity areas on which studies agreed and stakeholders associated with these areas to determine relevant participants in corridor management. Three or more of the 5 studies' resistance layers agreed in 63% of the study area. Areas in which all studies agree on resistance were of primarily low (66%, e.g., forest) and high (24%, e.g., urban) resistance. Agreement was lower in intermediate resistance areas (e.g., agriculture). Despite these differences, the studies largely agreed on areas with high levels of potential movement: >40% of high average (top 20%) current-flow pixels were also in the top 20% of current-flow agreement pixels (measured by low variation), indicating consensus connectivity areas (CCAs) as conservation priorities. Roughly 70% of the CCAs fell within village administrative boundaries, and 100% overlapped forest department management boundaries, suggesting that people live and use forests within these priority areas. Over 16% of total CCAs' area was within 1 km of linear infrastructure (437 road, 170 railway, 179 transmission line, and 339 canal crossings; 105 mines within 1 km of CCAs). In 2019, 78% of forest land diversions for infrastructure and mining in Madhya Pradesh (which comprises most of the study region) took place in districts with CCAs. Acute competition for land in this landscape with globally important wildlife corridors calls for an effective comanagement strategy involving local communities, forest departments, Appendix 1 and infrastructure planners. This article is protected by copyright. All rights reserved.

10.
PLoS One ; 9(11): e111207, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25393234

RESUMO

Even with global support for tiger (Panthera tigris) conservation their survival is threatened by poaching, habitat loss and isolation. Currently about 3,000 wild tigers persist in small fragmented populations within seven percent of their historic range. Identifying and securing habitat linkages that connect source populations for maintaining landscape-level gene flow is an important long-term conservation strategy for endangered carnivores. However, habitat corridors that link regional tiger populations are often lost to development projects due to lack of objective evidence on their importance. Here, we use individual based genetic analysis in combination with landscape permeability models to identify and prioritize movement corridors across seven tiger populations within the Central Indian Landscape. By using a panel of 11 microsatellites we identified 169 individual tigers from 587 scat and 17 tissue samples. We detected four genetic clusters within Central India with limited gene flow among three of them. Bayesian and likelihood analyses identified 17 tigers as having recent immigrant ancestry. Spatially explicit tiger occupancy obtained from extensive landscape-scale surveys across 76,913 km(2) of forest habitat was found to be only 21,290 km(2). After accounting for detection bias, the covariates that best explained tiger occupancy were large, remote, dense forest patches; large ungulate abundance, and low human footprint. We used tiger occupancy probability to parameterize habitat permeability for modeling habitat linkages using least-cost and circuit theory pathway analyses. Pairwise genetic differences (FST) between populations were better explained by modeled linkage costs (r>0.5, p<0.05) compared to Euclidean distances, which was in consonance with observed habitat fragmentation. The results of our study highlight that many corridors may still be functional as there is evidence of contemporary migration. Conservation efforts should provide legal status to corridors, use smart green infrastructure to mitigate development impacts, and restore habitats where connectivity has been lost.


Assuntos
Migração Animal , Grupos de População Animal/genética , Espécies em Perigo de Extinção , Tigres/genética , Animais , Ecossistema , Fluxo Gênico , Variação Genética/genética , Genética Populacional , Índia , Modelos Teóricos
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