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1.
Sci Total Environ ; 927: 172359, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38615771

RESUMO

Agriculture and its supply chain pose significant environmental threats. This study employs Life Cycle Assessment (LCA) to explore the environmental impact of fresh bell pepper production and distribution, comparing Urban and Peri-Urban Agriculture (UPA) with Rural Long-Distance Food Supply Systems (RLDFS). Four UPA scenarios (hydroponics, soil-based greenhouse, open-field conventional, and organic) and two RLDFS scenarios (soil-based greenhouse and open-field conventional) are evaluated using SimaPro, incorporating inputs from UPA practitioners and rural farmers. Results reveal an energy demand range of 0.011 to 5.5 kWh/kg eq., with urban greenhouses exhibiting the lowest consumption and hydroponics the highest due to lighting, ventilation, and irrigation. Hydroponics exhibits a global warming potential of 7.24 kg of CO2 eq·kg-1, with energy demand contributing over 95 %, surpassing other scenarios by 7-25 times, necessitating reduction for sustainability. RLDFS's environmental impact is dominated by transportation (over 70 %), meanwhile other UPA systems are influenced by irrigation, infrastructure, and fertilizers. Despite challenges, UPA-hydroponics proves to be 1.7 to 4.3 times more land-use-efficient than other scenarios, emphasizing its potential. The study highlights the need to address electricity usage in UPA-hydroponics for carbon footprint reduction. Despite challenges, hydroponics could contribute to sustainable food security, and RLDFS does not significantly lag in environmental performance compared to UPA other than Ozone layer depletion criteria attributed to fossil fuel usage in transportation. These insights offer valuable guidance for urban development and policy formulation, promoting sustainable agricultural practices and supporting policies for agronomic and supply chain sustainability.


Assuntos
Agricultura , Capsicum , Cidades , Abastecimento de Alimentos , Capsicum/crescimento & desenvolvimento , Agricultura/métodos , Abastecimento de Alimentos/estatística & dados numéricos , Meio Ambiente
2.
Cureus ; 15(11): e48363, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38060727

RESUMO

Calciphylaxis is an uncommon but serious and potentially life-threatening painful condition that is characterized by cutaneous vascular calcification and ischemia. It is typically seen in patients with end-stage renal disease but has been known to occur less commonly in patients with normal renal function. A rare but established etiology of non-uremic calciphylaxis is malignancy. We have thus far been successful in documenting an association between calciphylaxis and certain solid tumor types. The objective of this clinical case study is to better define a possible association between calciphylaxis and underlying malignancy.

3.
J Phys Condens Matter ; 33(10): 104003, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33264766

RESUMO

Structural and chemical order impact magnetic properties of solids, which are governed by spin-orbit coupling and exchange interaction. The ordered L10 phase of FePt is a key material to heat-assisted magnetic recording; to enable high storage density, a solid understanding is needed of structural and chemical disorder at small length scales, as well as associated modifications of the electronic band structure. Here, we investigate the effect of boron and copper additions (≲6 mol% Cu) on structural and magnetic properties of L10 FePt granular media. Two copper-driven mechanisms, although competing, can lead to improvements in both structural and magnetic properties. In particular, the Cu substitution on the Fe-site leads to a degradation of magnetic properties due to the delocalized electron orbitals originating from a larger Cu d-orbital occupancy. At the same time, Cu substitution leads to an enhanced crystallographic order and consequently magneto-crystalline anisotropy, which offsets the former effect to a large extent. Our study is based on magnetometry, x-ray absorption spectroscopy, ab-initio calculations and a phenomenological theory of disordered FePt granular media. We do not observe a sizable modification to Fe moments and electronic configuration; Cu reveals two different resonances associated with the presence and absence of Cu-B bonds that vary with total Cu concentration.

4.
PeerJ ; 8: e10164, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33088628

RESUMO

BACKGROUND: The COVID-19 pandemic is found to affect the mental health of the population. Undergraduate medical students are especially prone to mental health disorders and hence could be more vulnerable to the impact of the pandemic. METHODS: A prospective longitudinal study was conducted on 217 undergraduate medical students in a medical college at Chennai, India. Depression, anxiety, and stress levels were recorded using Depression Anxiety Stress Scale 21 Items (DASS21) before and during the COVID-19 outbreak in India in December 2019 and June 2020, respectively. In the follow-up survey, in addition to DASS21, the Pittsburgh Sleep Quality Index to assess sleep quality and a self-administered questionnaire to assess the impact of COVID-19 related stressors were used. The self-administered questionnaire assessed the status of COVID-19 testing, interactions with COVID-19 patients, self-perceived levels of concerns and worries related to academics (COVID-19-AA (academic apprehensions)) and those pertaining to the self and family/friends (COVID-19-GA (general apprehensions)). Cross-sectional and longitudinal comparison of overall scores of depression, anxiety, and stress and scores stratified by gender, year of study, place of residence and monthly family income were performed. Predictors for depression, anxiety, and stress during COVID-19 were investigated using adjusted binary logistic regression analysis and results were expressed as adjusted odds ratio with 95% confidence interval (CI). A P value < 0.05 was considered statistically significant. RESULTS: The average scores of depression, anxiety, and stress during the baseline survey were 7.55 ± 7.86, 4.6 ± 6.19 and 7.31 ± 7.34 with the prevalence (95% Cl) of 33.2% [27-39.9%], 21.2% [16-27.2%] and 20.7% [15.5-26.7%]; in follow-up survey, the mean scores were 8.16 ± 8.9, 6.11 ± 7.13 and 9.31 ± 8.18 with the prevalence being 35.5% [29.1-42.2%], 33.2% [27-39.9%] and 24.9% [19.3-31.2%] for depression, anxiety, and stress respectively. There was a significant increase in both the prevalence and levels of anxiety and stress (P < 0.001), with depression remaining unchanged during COVID-19, irrespective of gender, year of study, place of residence and family's monthly income. Poor sleep quality, higher levels of baseline depression, anxiety, and stress, higher COVID-19-GA, COVID-19 patients in family/friends and direct interactions with COVID-19 patients were found to be significant predictors of negative mental health in undergraduate medical students. COVID-19-AA was not significantly associated with depression, anxiety, and stress. CONCLUSION: The COVID-19 pandemic appears to negatively affect the mental health of the undergraduate medical students with the prevalence and levels of anxiety and stress being increased, and depression symptoms remaining unaltered. Addressing and mitigating the negative effect of COVID-19 on the mental health of this population is crucial.

5.
J Clin Diagn Res ; 11(9): ZC68-ZC70, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29207837

RESUMO

INTRODUCTION: The restoration of a severely damaged tooth usually needs a post and core as a part of treatment procedure to provide a corono - radicular stabilization. Biodentine is a class of dental material which possess high mechanical properties with excellent biocompatibility and bioactive behaviour. The sealing ability coupled with optimum physical properties could make Biodentine an excellent option as a core material. AIM: The aim of the study was to determine the fracture resistance of Biodentine as a core material in comparison with resin modified glass ionomer and composite resin. MATERIALS AND METHODS: Freshly extracted 30 human permanent maxillary central incisors were selected. After endodontic treatment followed by post space preparation and luting of Glass fibre post (Reforpost, Angelus), the samples were divided in to three groups based on the type of core material. The core build-up used in Group I was Biodentine (Septodont, France), Group II was Resin-Modified Glass Ionomer Cement (GC, Japan) and Group III was Hybrid Composite Resin (TeEconom plus, Ivoclar vivadent). The specimens were subjected to fracture toughness using Universal testing machine (1474, Zwick/Roell, Germany) and results were compared using One-way analysis of variance with Tukey's Post hoc test. RESULTS: The results showed that there was significant difference between groups in terms of fracture load. Also, composite resin exhibited highest mean fracture load (1039.9 N), whereas teeth restored with Biodentine demonstrated the lowest mean fracture load (176.66 N). Resin modified glass ionomer exhibited intermediate fracture load (612.07 N). The primary mode of failure in Group I and Group II was favourable (100%) while unfavourable fracture was seen in Group III (30%). CONCLUSION: Biodentine, does not satisfy the requirements to be used as an ideal core material. The uses of RMGIC's as a core build-up material should be limited to non-stress bearing areas. Composite resin is still the best core build-up material owing to its high fracture resistance and bonding to tooth.

6.
Artigo em Inglês | MEDLINE | ID: mdl-29201781

RESUMO

Inguinoscrotal bladder herniation has a reported incidence of 1 to 4%. Although small bladder herniations are noted at the time of inguinal hernia repair, large bladder herniation into the scrotum is rare. These patients have a unique presentation of signs and symptoms. We report a case of a male patient of age 64 years who had a large inguinoscrotal hernia with bladder. He successfully underwent hernioplasty after repositioning of the bladder. Now, he is symptom-free and on follow-up. How to cite this article: Mohan A, Srinivasan K. Scrotal Cystocele in a Sliding Left Inguinoscrotal Hernia: A Case Report and Review of Literature. Euroasian J Hepato-Gastroenterol 2017;7(1):87-88.

7.
J Clin Diagn Res ; 10(11): ZD21-ZD23, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28050518

RESUMO

Any insult to the pulp during its development causes cessation of dentin formation and root growth. Pulpal status and degree of root development are the decisive factors in the treatment approach. Various treatment options have been tried like surgery with root-end sealing, calcium hydroxide-apexification, placement of apical plug and regenerative endodontic procedures to induce apexogenesis. An ideal scenario for a necrosed tooth with immature root would be continued root development coupled with regeneration of pulp tissue. We report a case, where revitalization was done using Platelet-Rich Fibrin (PRF) as a scaffold in immature mandibular molar tooth.

9.
Biochem Biophys Res Commun ; 454(1): 84-8, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25450361

RESUMO

Small nuclear RNAs (snRNAs) are <200 nucleotide non-coding uridylate-rich RNAs. Although the functions of many snRNAs remain undetermined, a population of snRNAs is produced during the early phase of infection of cells by vaccinia virus. In the present study, we demonstrate a direct correlation between expression of the cytoprotective enzyme heme oxygenase-1 (HO-1), suppression of selective snRNA expression, and inhibition of vaccinia virus infection of macrophages. Hemin induced HO-1 expression, completely reversed virus-induced host snRNA expression, and suppressed vaccinia virus infection. This involvement of specific virus-induced snRNAs and associated gene clusters suggests a novel HO-1-dependent host-defense pathway in poxvirus infection.


Assuntos
Heme Oxigenase-1/genética , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , Vaccinia virus/patogenicidade , Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Imunidade Inata/genética , Macrófagos/metabolismo , Macrófagos/virologia , Família Multigênica , Infecções por Poxviridae/imunologia , Infecções por Poxviridae/terapia , RNA Nuclear Pequeno/genética , RNA Nuclear Pequeno/metabolismo , Vaccinia virus/imunologia
10.
Arch Pharm (Weinheim) ; 347(8): 540-51, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24853356

RESUMO

Medicinal chemistry has been benefited by combinatorial chemistry and high-throughput parallel synthesis. Ionic liquids reduce the materials and energy intensity of chemical processes and products, minimize or eliminate the dispersion of harmful chemicals in the environment, maximize the use of renewable resources and extend the durability and recyclability of products. It is possible to tune the physical and chemical properties by varying the nature of the cations and anions. Ionic liquids can be easily recovered, cleaned up, and reused repeatedly.


Assuntos
Técnicas de Química Combinatória/métodos , Compostos Heterocíclicos/síntese química , Líquidos Iônicos/química , Solventes/química , Compostos Heterocíclicos/química , Estrutura Molecular
11.
PLoS One ; 8(8): e69982, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23940536

RESUMO

Targeting papain family cysteine proteases is one of the novel strategies in the development of chemotherapy for a number of diseases. Novel cysteine protease inhibitors derived from 1-pyridylimidazo[1,5-a]pyridine representing pharmacologically important class of compounds are being reported here for the first time. The derivatives were initially designed and screened in silico by molecular docking studies against papain to explore the possible mode of action. The molecular interaction between the compounds and cysteine protease (papain) was found to be very similar to the interactions observed with the respective epoxide inhibitor (E-64c) of papain. Subsequently, compounds were synthesized to validate their efficacy in wet lab experiments. When characterized kinetically, these compounds show their Ki and IC50 values in the range of 13.75 to 99.30 µM and 13.40 to 96.50 µM, respectively. The thermodynamics studies suggest their binding with papain hydrophobically and entropically driven. These inhibitors also inhibit the growth of clinically important different types of Gram positive and Gram negative bacteria having MIC50 values in the range of 0.6-1.4 µg/ml. Based on Lipinski's rule of Five, we also propose these compounds as potent antibacterial prodrugs. The most active antibacterial compound was found to be 1-(2-pyridyl)-3-(2-hydroxyphenyl)imidazo[1,5-a]pyridine (3a).


Assuntos
Inibidores de Cisteína Proteinase/química , Papaína/química , Piridinas/química , Inibidores de Cisteína Proteinase/síntese química , Ligação Proteica , Estrutura Secundária de Proteína , Piridinas/síntese química , Termodinâmica
12.
Nano Lett ; 12(5): 2595-8, 2012 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-22519694

RESUMO

In perpendicular hard disk memory media, nanometric magnetic Co-rich grains are separated by a ∼1 nm thick nonmagnetic and preferably amorphous intergranular phase (IP). Attempts at observing the IP structure at high resolution using TEM have been obstructed by the superposition of lattice fringes from the crystalline grains extending into the IP region in images. Here we present the first images of a magnetic recording medium produced using a spherical aberration-corrected TEM showing the true amorphous IP structure in contrast to the crystalline grains, allowing the accurate determination of the grain-IP interface and the grain and IP dimensions. It is shown that these aberration-corrected TEM images are functionally superior for analyzing certain features of the ultrahigh capacity data recording media.

13.
Nano Lett ; 11(9): 3751-4, 2011 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-21806054

RESUMO

The key component of a hard disk medium is a Co-based magnetic layer (ML) grown on a Ru seed layer. The ML nanostructure, composed of less than 10 nm grains, is believed to be controlled by this seed layer. We successfully used scanning transmission electron microscopy energy dispersive spectrometry simultaneous composition-based imaging and Moiré pattern analysis for determining the mutual structural and orientation relationship between the two layers revealing a grain-to-grain agreement. The method presented here can be utilized for observing structural correlations between consecutive polycrystalline thin film layers in general.

14.
ISRN Org Chem ; 2011: 434613, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-24052822

RESUMO

Remarkably high-speed synthesis of 2-substituted amino-4-aryl thiazoles in polar solvents with a minimum threshold polarity index of 4.8 was found to proceed to completion in just 30-40 sec. affording excellent yields of thiazoles under ambient temperature conditions without the use of any additional catalyst. The purification-free procedure afforded libraries based around a known pharmacophore, namely, substituted arylthiazoles and generated samples of high purity. In terms of combinatorial synthesis in a single solution phase, our protocol is significantly better than those hitherto reported and is amenable for HTS. The in vitro biological tests of some thiazoles showed good activity towards gram-positive bacteria, gram-negative bacteria and fungi comparable with the standard drugs, nitrofurantoin and griseofulvin, for their antibacterial and antifungal activities, respectively.

15.
Chem Biol Drug Des ; 72(3): 197-204, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18680533

RESUMO

Some novel chemically synthesized 2,4,5-trisubstituted imidazoles from aryl aldehydes and 1,2-diketones or alpha-hydroxyketone were screened against eight different human pathogenic bacteria and fungi. Seven compounds were found to be active against different bacteria. These compounds showed variation in activity and were found to be active against Gram-positive as well as Gram-negative bacteria. Compound 4-(4,5-diphenyl-1H-imidazol-2-yl)-phenol, 3d was the only compound which showed activity against Klebsiella pneumoniae while rest of the compounds did not show significant activity against this micro-organism. Minimum inhibitory concentrations of the compounds were in the range of 0.50 to 6.1 microg/mL and minimum bactericidal concentration ranges from 1.11 to 12.9 microg/mL. The candidature of active compounds to be an effective and novel drug was examined based on Lipinski's rule of Five which explained ClogP, LogS, H-bond acceptors, H-Bond donors and rotational bonds. Compounds 3a-d and 3f satisfies Lipinski's rule of Five and could be proposed as potent new antibacterial drugs.


Assuntos
Antibacterianos/farmacologia , Imidazóis/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Humanos , Imidazóis/síntese química , Imidazóis/química , Concentração Inibidora 50 , Klebsiella pneumoniae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Fenóis/síntese química , Fenóis/farmacologia
16.
Ultrason Sonochem ; 15(5): 853-62, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18078777

RESUMO

This method describes the results of the optimized conditions for the one-pot synthesis of benzo[b]furans/nitro benzo[b]furans via Sonogashira coupling-5-endo-dig-cyclization under ultrasonic irradiation at ambient temperature in the absence of copper, ligand and amine. The protocol tolerates wide range of functional groups present in both the coupling components, especially base labile nitro group was not affected under these mild conditions giving excellent yields of the nitro benzo[b]furans. The formation of Pd(0) nanoparticles as the active species has been shown by TEM analysis and the unique role of ultrasound in promoting the total sonochemical protocol has been substantiated by way of control experiments.

17.
Bioorg Med Chem ; 15(21): 6705-15, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17765545

RESUMO

A series of 2-amino-5-oxo-4-phenyl-5,6,7,8-tetrahydroquinoline-3-carbonitrile and various analogues have been synthesized in excellent isolated yields starting from various arylidenemalononitrile and 3-amino-2-cyclohexen-1-one in 1-propanol as solvent at reflux temperature in the absence of any added catalyst. All the synthesized compounds were evaluated for their antifungal activity. The relationship between functional group variation and biological activity of the evaluated compounds is discussed in the article.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Fungos/efeitos dos fármacos , Nitrilas/farmacologia , Quinolinas/farmacologia , Antifúngicos/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Hifas/efeitos dos fármacos , Nitrilas/síntese química , Quinolinas/síntese química
19.
Transfusion ; 46(9): 1589-92, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16965588

RESUMO

BACKGROUND: Mass smallpox vaccination with live vaccinia virus has been considered as a preventive measure to counter bioterrorism involving smallpox. This has raised concerns about the possibility of vaccinia virus being transmitted from vaccinated blood donors to recipients. The results of this study could be used to define an appropriate deferral period for blood donors (vaccinated against smallpox) to ensure safety of the blood supply. STUDY DESIGN AND METHODS: A procedure was developed to culture vaccinia virus from plasma and peripheral blood mononuclear cells (PBMNCs) of vaccinees enrolled in three smallpox vaccine clinical trials. A total of 665 plasma and PBMNC samples were obtained from 95 vaccinated subjects. RESULTS: Vaccinia viremia was not detected by virus culture from plasma and PBMNC samples of healthy vaccinees 3 to 56 days after vaccination under our assay conditions. Plasma viremia assay had a sensitivity of approximately 66 plaque-forming units per mL with a Vero cell culture assay. CONCLUSION: The results of this study present evidence that in the case of mass vaccination, the risk of transmission of vaccinia virus by blood transfusion would likely be low.


Assuntos
Leucócitos Mononucleares/citologia , Vacina Antivariólica/administração & dosagem , Varíola/prevenção & controle , Vacinação/normas , Animais , Bioterrorismo , Técnicas de Cultura de Células , Chlorocebus aethiops , Ensaios Clínicos como Assunto , Contraindicações , Humanos , Vacinação em Massa , Segurança , Varíola/transmissão , Vacina Antivariólica/efeitos adversos , Vaccinia virus/isolamento & purificação , Células Vero , Viremia/induzido quimicamente
20.
Microbes Infect ; 8(8): 2236-44, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16782382

RESUMO

Cytomegalovirus (CMV) retinitis is characterized by alterations in retinal cell function and host responses to virus replication. The goal of this study was to evaluate the induction of cyclooxygenase-2 (COX-2) and prostaglandin (PGE) in CMV infected human retinal pigment epithelial (RPE) cells and to determine their effect on virus replication. CMV immediate early (IE) protein and COX-2 proteins were identified in RPE cells in retinal tissue sections from patients with CMV retinitis. COX-2 mRNA and protein were induced after CMV infection of human RPE cell cultures. CMV infection of RPE cells induced translocation of NF-kappaB from the cytoplasm to the nucleus. PGE1 and PGE2 were significantly (p<0.001) increased in human RPE cell cultures infected with CMV. Inhibition of CMV IE gene by antisense oligonucleotides abrogated induction of mRNA for COX-2 and protein synthesis of COX-2 and PGE2. PGE enhanced CMV plaque formation and real time PCR analysis revealed that PGE treatment significantly increased CMV DNA copy numbers. These studies demonstrate that when CMV replicates within human RPE cells, COX-2 induction augments virus replication via the PGE pathway. The induction of COX-2 and PGE during retinal CMV infection may augment virus replication and alter a variety of retinal physiological responses.


Assuntos
Ciclo-Oxigenase 2/biossíntese , Citomegalovirus/fisiologia , Epitélio Pigmentado Ocular/virologia , Prostaglandinas/biossíntese , Replicação Viral , Núcleo Celular/química , Células Cultivadas , Ciclo-Oxigenase 2/genética , Citomegalovirus/crescimento & desenvolvimento , Retinite por Citomegalovirus/patologia , Retinite por Citomegalovirus/virologia , Citoplasma/química , DNA Viral/análise , Expressão Gênica , Humanos , Proteínas Imediatamente Precoces/análise , Proteínas Imediatamente Precoces/antagonistas & inibidores , Imuno-Histoquímica , Microscopia de Fluorescência , NF-kappa B/metabolismo , Oligonucleotídeos Antissenso/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , Retina/química , Ensaio de Placa Viral , Proteínas Virais/análise
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