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1.
J Am Chem Soc ; 146(22): 15301-15308, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38785321

RESUMO

Designing supramolecular architectures with uncommon geometries has always been a key goal in the field of metal-ligand coordination-driven self-assembly. It acquires added significance if functional building units are employed in constructing such architectures for fruitful applications. In this report, we address both these aspects by developing a water-soluble Pd16L8 coordination cage 1 with an unusual square orthobicupola geometry, which was used for selective aerobic oxidation of aryl sulfides. Self-assembly of a benzothiadiazole-based tetra-pyridyl donor L with a ditopic cis-[(tmeda)Pd(NO3)2] acceptor [tmeda = N,N,N',N'-tetramethylethane-1,2-diamine] produced 1, and the geometry was determined by single-crystal X-ray diffraction study. Unlike the typically observed tri- or tetrafacial barrel, the present Pd16L8 coordination assembly features a distinctive structural topology and is a unique example of a water-soluble molecular architecture with a square orthobicupola geometry. Efficient and selective aerobic oxidation of sulfides to sulfoxides is an important challenge as conventional oxidation generally leads to the formation of sulfoxide along with toxic sulfone. Cage 1, designed with a ligand containing a benzothiadiazole moiety, demonstrates an ability to photogenerate reactive oxygen species (ROS) in water, thus enabling it to serve as a potential photocatalyst. The cage showed excellent catalytic efficiency for highly selective conversion of alkyl and aryl sulfides to their corresponding sulfoxides, therefore without the formation of toxic sulfones and other byproducts, under visible light in aqueous medium.

2.
Inorg Chem ; 63(5): 2569-2576, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38241721

RESUMO

Developing sensitive, rapid, and convenient methods for the detection of residual toxic pesticides is immensely important to prevent irreversible damage to the human body. Luminescent metal-organic cages and macrocycles have shown great applications, and designing highly emissive supramolecular systems in dilute solution using metal-ligand coordination-driven self-assembly is demanded. In this study, we have demonstrated the development of a silver-carbene bond directed tetranuclear silver(I)-octacarbene metallacage [Ag4(L)2](PF6)4 (1) based on an aggregation-induced emissive (AIE) cored 1,1',1″,1‴-((1,4-phenylenebis(ethene-2,1,1-triyl))tetrakis(benzene-4,1-diyl))tetrakis(3-methyl-1H-imidazol-3-ium) salt (L). A 36-fold enhanced emission was observed after metallacage (1) formation when compared with the ligand (L) in dilute solution due to the restriction of intramolecular motions imparted by metal-ligand coordination. Such an increase in fluorescence made 1 a potential candidate for the detection of a broad-spectrum pesticide, 2,6-dichloro-nitroaniline (DCN). 1 was able to detect DCN efficiently by the fluorescence quenching method with a significant detection limit (1.64 ppm). A combination of static and dynamic quenching was applicable depending on the analyte concentration. The use of silver-carbene bond directed self-assembly to exploit coordination-induced emission as an alternative to AIE in dilute solution and then apply this approach to solve health and safety concerns is noteworthy and carries a lot of potential for future developments.

3.
J Pediatr Surg ; 59(2): 305-309, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38030532

RESUMO

AIM: Paediatric-preoperative anaemia management is challenging in settings where clinical judgment is used to diagnose anaemia owing to a lack of timely, affordable preoperative haemoglobin testing. We analysed anaemia management in such a setting after the introduction of point-of-care bedside haemoglobin testers. METHOD: 1033 children who underwent surgery at a hospital in Bangladesh were included in this study. 569 underwent major surgery, and 464 underwent minor surgery and belonged to predominantly ASA category 1 or 2. RESULTS: 940/1033 children underwent preoperative anaemia testing. Average haemoglobin was 11.7 g/dL. 103/1033 children were deemed clinically anaemic. However, 285 children were found to have anaemia based on bedside testing. Sensitivity of clinical judgement was 33.68% (95 % CI 28.22%-39.49%), and the specificity was 99.08% (95 % CI 98.02%-99.66%). 63/1033 had preoperative anaemia treatment, of whom 60 underwent transfusion. Subgroup analysis of children with haemoglobin <10 g/dL (n = 124) was done to compare conservative vs liberal transfusion strategy. 43/124 of this subset was transfused. Average length of stay for those transfused was 11.7 days, and those who weren't was 9.9 days (p = 0.087). 4 patients in the transfused subgroup required post-op ICU, and only 1 patient in the conservatively managed arm required ICU (p = 0.048). CONCLUSION: This study demonstrates the positive impact of bedside haemoglobin testers as they have resulted in a significantly higher proportion of children diagnosed with anaemia at a fraction of the cost and logistics involved in laboratory testing. Further research on haemoglobin thresholds is required to understand the safety and long-term impact of restrictive transfusion in the surgical context. LEVEL OF EVIDENCE: 2c (Grading as per the Oxford Centre for Evidence Based Medicine).


Assuntos
Anemia , Transfusão de Eritrócitos , Humanos , Criança , Anemia/diagnóstico , Anemia/etiologia , Anemia/terapia , Hemoglobinas/análise , Transfusão de Sangue , Estudos Prospectivos
4.
Inorg Chem ; 62(28): 11037-11043, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37411006

RESUMO

A tetraphenylethylene (TPE)-based flexible imidazolium (L) salt was used to develop a di-nuclear silver(I)-tetracarbene (1) complex. Coordination-induced rigidity upon formation of 1 exhibited a 6-fold increase in emission intensity in acetonitrile compared to starting L. Despite TPE being a well-known aggregation-induced emissive moiety, AgI-N-heterocyclic carbene (NHC) complex 1 had a remarkably higher fluorescence emission (4-fold) in dilute solution when compared with L in its aggregated state. Finally, this enhanced emission was used to institute a new platform for an artificial light-harvesting system. 1 acted as an energy donor and efficiently transferred energy to Eosin Y (ESY) with a high saturation at a 67:1 (1/ESY) molar ratio. Use of rigidification-induced emission of the AgI-NHC complex to fabricate a light-harvesting scaffold is a new approach and can greatly impact the generation of smart materials.

5.
Vacunas ; 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37362841

RESUMO

The outbreak of SARS-CoV-2, an etiologic agent of the COVID-19 pandemic disease in late December 2019 has left the whole world aghast with huge health and economic losses. Due to a lack of specific knowledge and understanding at the initial stages, an unprecedented rise in COVID-19 cases has been recorded globally. Various preventive measures and strategies were implemented, however, for the radical control of SARS-CoV-2 infections; it seems that the only effective way to control the ongoing infections is large-scale vaccination. So far, WHO has approved 11 vaccines for emergency use namely Pfizer/BioNTech, Oxford/Astra Zeneca, Johnson and Johnson, Moderna, Covilo, Novavax, Covovax, Spikevax, Can Sino, Comirnaty, and Coronavac while five other needs approval. The worldwide vaccination dataset reveals that 65.7% of the world population has received their first dose of the COVID-19 vaccine. As a consequence of the proactive implementation of India's vaccination program, a historical milestone of administering over 1.9 billion doses of COVID-19 vaccines have been achieved on 19th May 2022. This review summarizes the different types of traditional and modern vaccine designing strategies with an emphasis on COVID-19. Moreover, the review highlights the status of vaccines for COVID-19 approved in India which includes both indigenous and non-indigenous vaccines. The present article also encompasses vaccine designing and developmental strategies, efficacy, safety profile and usage among the population, and the efficacy of modern vaccines over traditional ones.


El brote de SARS-CoV-2, un agente etiológico de la enfermedad pandémica COVID-19, a fines de diciembre de 2019, ha dejado al mundo entero horrorizado con enormes pérdidas económicas y de salud. Debido a la falta de conocimiento y comprensión específicos en las etapas iniciales, se ha registrado un aumento sin precedentes en los casos de COVID-19 a nivel mundial. Sin embargo, se implementaron diversas medidas y estrategias preventivas para el control radical de las infecciones por SARS-CoV-2; parece que la única forma eficaz de controlar las infecciones en curso es la vacunación a gran escala. Hasta el momento, la OMS ha aprobado 11 vacunas para uso de urgencia Pfizer/BioNTech, Oxford/Astra Zeneca, Johnson and Johnson, Moderna, Covilo, Novavax, Covovax, Spikevax, Can Sino, Comirnaty y Coronavac, mientras que otras cinco necesitan aprobación. El conjunto de datos de vacunación mundial revela que el 65,7% de la población mundial ha recibido su primera dosis de la vacuna COVID-19. Como consecuencia de la implementación proactiva del programa de vacunación de la India, el 19 de mayo de 2022 se logró un hito histórico de administrar más de 1900 millones de dosis de vacunas contra el COVID-19. Esta revisión resume los diferentes tipos de estrategias de diseño de vacunas tradicionales y modernas con énfasis sobre COVID-19. Además, la revisión destaca el estado de las vacunas para COVID-19 aprobadas en India, que incluye vacunas tanto indígenas como no indígenas. El presente artículo también abarca estrategias de diseño y desarrollo de vacunas, eficacia, perfil de seguridad y uso entre la población, y la eficacia de las vacunas modernas sobre las tradicionales.

6.
Hyg Environ Health Adv ; 6: 100055, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37102160

RESUMO

The usage and the demand for personal protective equipments (PPEs) for our day-to-day survival in this pandemic period of COVID-19 have seen a steep rise which has consequently led to improper disposal and littering. Fragmentation of these PPE units has eventually given way to micro-nano plastics (MNPs) emission in the various environmental matrices and exposure of living organisms to these MNPs has proven to be severely toxic. Numerous factors contribute to the toxicity imparted by these MNPs that mainly include their shape, size, functional groups and their chemical diversity. Even though multiple studies on the impacts of MNPs toxicity are available for other organisms, human cell line studies for various plastic polymers, other than the most common ones namely polyethylene (PE), polystyrene (PS) and polypropylene (PP), are still at their nascent stage and need to be explored more. In this article, we cover a concise review of the literature on the impact of these MNPs in biotic and human systems focusing on the constituents of the PPE units and the additives that are essentially used for their manufacturing. This review will subsequently identify the need to gather scientific evidence at the smaller level to help combat this microplastic pollution and induce a more in-depth understanding of its adverse effect on our existence.

7.
J Biomech Eng ; 145(5)2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36416287

RESUMO

Biphasic poro-viscoelastic constitutive material model (BPVE) captures both the fluid flow dependent and independent behavior of cartilage under stress relaxation type indentation. A finite element model based on BPVE formulation was developed to explore the sensitivity of the model to Young's modulus, Poisson's ratio, permeability, and viscoelastic constitutive parameters expressed in terms of Prony series coefficients. Then we fit the numerical model to experimental force versus time curves from stress relaxation indents on bovine tibial plateaus to extract the material properties. Measurements were made over the period of two days to capture the material property changes that resulted from trypsin-induced degradation. We measured spatial and temporal changes in mechanical properties in the cartilage. The areas of degradation were characterized by an increase in both permeability and summation of Prony series shear relaxation amplitude constants. These findings suggest that cartilage degradation reduces the intrinsic viscoelastic properties of the solid phase of the tissue in addition to impairing its capacity to offer frictional drag to the interstitial fluid flow (permeability). The changes in material properties are measurable well before structural degradation occurs.


Assuntos
Cartilagem Articular , Animais , Bovinos
8.
Infection ; 50(5): 1053-1066, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35489015

RESUMO

PURPOSE: Apart from the global disease burden of acute COVID-19 disease, the health complications arising after recovery have been recognized as a long-COVID or post-COVID-19 syndrome. Evidences of long-COVID symptoms involving various organ systems are rapidly growing in literature. The objective was to perform a rapid review and evidence mapping of systemic complications and symptoms of long-COVID and underlying pathophysiological mechanisms. METHODS: Publications reporting clinical trials, observational cohort studies, case-control studies, case-series, meta-analysis, and systematic reviews, focusing on the squeal of the disease, consequences of COVID-19 treatment/hospitalization, long-COVID, chronic COVID syndrome, and post acute COVID-19 were reviewed in detail for the narrative synthesis of frequency, duration, risk factors, and pathophysiology. RESULTS: The review highlights that pulmonary, neuro-psychological, and cardiovascular complications are major findings in most epidemiological studies. However, dysfunctional gastrointestinal, endocrine, and metabolic health are recent findings for which underlying pathophysiological mechanisms are poorly understood. Analysis of the clinical trial landscape suggests that more than 50% of the industry-sponsored trials are focused on pulmonary symptoms. In contrast to the epidemiological trends and academic trials, cardiovascular complications are not a focus of industry-sponsored trials, suggestive of the gaps in the research efforts. CONCLUSION: The gap in epidemiological trends and academic trials, particularly concerning cardiovascular complications not being a focus of industry-sponsored trials is suggestive of the gaps in research efforts and longer follow-up durations would help identify other long-COVID-related health issues such as reproductive health and fertility.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , COVID-19/complicações , COVID-19/epidemiologia , Hospitalização , Humanos , Fatores de Risco , Síndrome de COVID-19 Pós-Aguda
9.
Br Poult Sci ; : 1-6, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30929462

RESUMO

1. The effect of supplementing water-soluble vitamin E analogues 6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (trolox) and butylated hydroxy toluene (BHT) was studied in two separate experiments. 2. In the first experiment, trolox was supplemented at 0.2 mM, 0.4 mM and 0.8 mM concentrations along with N-methylacetamide (MA; 12% final concentration) and semen was cryopreserved in 0.5 ml French straws. Different semen parameters and fertility were assessed from post-thaw samples. 3. Sperm motility, live sperm, and mitochondrial activity were significantly lower (P < 0.05) in cryopreserved semen. Lipid peroxidation (LPO) was significantly higher (P < 0.05) in cryopreserved semen that was reduced by trolox supplementation. The treatment containing trolox at 0.2 mM concentration produced significantly higher (P < 0.05) fertility compared to unsupplemented cryopreservation treatment. 4. In the second experiment, BHT was supplemented at 0.25 mM, 0.5 mM, and 1 mM concentrations along with MA during semen cryopreservation. 5. Sperm motility, live sperm and MTT dye reduction test were significantly lower (P < 0.05) in cryopreserved semen. These parameters declined with increasing BHT concentration. Abnormal sperm was significantly higher (P < 0.05) in the BHT supplemented treatments. The sperm chromatin dispersion (SCD) test was significantly higher (P < 0.05) in cryopreserved samples and was highest in samples supplemented with 0.5 mM and 1 mM BHT. The percentage fertility was significantly lower (P < 0.05) in cryopreserved semen and BHT supplementation did not improve fertility. 6. In conclusion, trolox supplementation at 0.2 mM concentration during semen cryopreservation improved fertility, whereas BHT supplementation resulted in a decline in post-thaw semen parameters.

10.
Indian J Otolaryngol Head Neck Surg ; 68(2): 131-4, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27340625

RESUMO

This study aims to define the surgical boundaries of adenoidectomy by demonstrating that recurrence of adenoids and its symptoms can be avoided if a complete adenoidectomy is performed, by following these surgical limits. A prospective descriptive study was carried out at Speciality ENT Hospital, Mumbai, India. Endoscopic adenoidectomy was performed in 83 patients using coblation technology. In all patients, adenoids were removed superiorly till the periosteum over the body of sphenoid; posteriorly till the pharyngobasilar fascia; laterally till fossa of Rosenmuller in the posterior part and till the torus tubarius in the anterior part; and inferiorly till the Passavant's ridge. The patients were followed up postoperatively and a nasal endoscopy was done at the end of 1 year to look for any recurrence or regrowth of adenoids, so as to determine the efficacy of the procedure. A total of 83 patients underwent adenoidectomy with a mean age of 12.80 years. 12 patients were lost to follow up. Of the remaining 71 patients, no patient showed any evidence of recurrence of adenoid on follow-up nasal endoscopy done at the end of 1 year. Recurrence of adenoid post adenoidectomy is not seen if there is complete removal of adenoids. So it is essential that all adenoid tissue be removed during adenoidectomy. The complete removal of adenoids can be ensured by following the surgical limits of adenoidectomy.

11.
BMJ Case Rep ; 20152015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26643183

RESUMO

Pyogenic granuloma is a benign lesion of the skin and mucosa commonly known to occur in the head and neck region. The current literature has not yet identified its occurrence within the conchal bowl, a condition that leads to obstruction of the external auditory meatus. We present the case of a 28-year-old man who presented with a history of 3-4 weeks of a rapidly enlarging pedunculated lesion within the conchal bowl of the right ear and conductive hearing loss. Initial management included excision under local anaesthesia. The histological report concluded that it was a pyogenic granuloma. Later, reoccurrence was treated with a more definitive excision under general anaesthesia. During follow-up, the operative site was seen to have healed by secondary intention without reoccurrence. Although a pyogenic granuloma within the conchal bowl is benign, early therapeutic excision is important for histological diagnosis as much as to relieve consequential secondary obstruction and conductive hearing loss.


Assuntos
Antibacterianos/administração & dosagem , Orelha Externa/patologia , Ácido Fusídico/administração & dosagem , Granuloma Piogênico/complicações , Perda Auditiva Condutiva/etiologia , Adulto , Orelha Externa/cirurgia , Ácido Fusídico/análogos & derivados , Granuloma Piogênico/tratamento farmacológico , Granuloma Piogênico/patologia , Granuloma Piogênico/cirurgia , Humanos , Hidrocortisona/administração & dosagem , Masculino , Pomadas , Resultado do Tratamento
12.
Eur J Med Chem ; 68: 132-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23973825

RESUMO

A new series of disubstituted alkynes was obtained by microwave induced internal splitting of the corresponding ß-oxo-alkylidenetriphenylphosphoranes. The antimicrobial potential of these conjugated alkynes and phosphoranes was assayed in vitro against three Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis, Staphylococcus epidermidis), three Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae) and five fungal strains (Aspergillus niger, Candida albicans, Aspergillus flavus, Candida rugosa, Saccharomyces cerevisiae). The 3-pyridylalkyne derivatives viz., 3-(6-chloropyridin-3-yl)propynenitrile (6a), 3-(2-chloropyridin-3-yl)propynenitrile (6b), ethyl 3-(6-chloropyridin-3-yl)propiolate (6c), iso-propyl 3-(6-chloropyridin-3-yl)propiolate (6d) and 3-(2,6-dichloro-5-fluoropyridin-3-yl)propynenitrile (6e) were found to be highly potent towards all tested microorganisms except E. coli.


Assuntos
Alcinos/síntese química , Alcinos/farmacologia , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Acetileno/química , Acetileno/farmacologia , Alcinos/química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Testes de Sensibilidade Microbiana , Estrutura Molecular
13.
Bioorg Med Chem Lett ; 21(21): 6510-4, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21924612

RESUMO

Indole and its derivatives undergo smooth conjugate addition onto en-1,4-dione derived from isatin and acetophenone, in the presence of a catalytic amount of molecular iodine in acetonitrile under mild conditions to afford a novel class of 3-(1-(1H-indol-3-yl)-2-oxo-2-phenylethyl)indolin-2-one derivatives in good yields with high degree of 1,4-selectivity. Some of these compounds are found to exhibit modest antibacterial and antifungal properties.


Assuntos
Antibacterianos/química , Antifúngicos/química , Indóis/química , Iodo/química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Catálise , Iodo/farmacologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Espectrofotometria Infravermelho
14.
Bioorg Med Chem Lett ; 21(13): 3890-3, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21641208

RESUMO

A simple and efficient synthetic approach toward a series of chiral aryl boronate esters, starting from D-xylose, as anti-microbial agents, is described herein. Minimum inhibitory concentration and zone of inhibition revealed that these derivatives exhibit potent anti-bacterial and anti-fungal properties. Herein, we report the first anti-microbial activity of this class of compounds. All products have been characterized by NMR ((1)H, (13)C and (11)B), IR, elemental and mass spectral study.


Assuntos
Antibacterianos , Antifúngicos , Bactérias/efeitos dos fármacos , Ésteres/síntese química , Ésteres/farmacologia , Fungos/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Boratos/síntese química , Boratos/química , Boratos/farmacologia , Ésteres/química , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Xilose/síntese química , Xilose/química , Xilose/farmacologia
15.
Eur J Med Chem ; 45(1): 78-84, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19931223

RESUMO

The formation of N- and O-propargylated quinazoline derivatives 2, 3 from quinazol-4-ones 1 was theoretically predicted by optimizations at B3LYP/6-31G* level, analysed kinetically and thermodynamically. Theoretical predictions are validated by experiment to observe the trends and found deviation. Thus, compound 1 was propargylated in basic media to obtain compound 2 and 3 in definite proportions. Each compound was further subjected to [3+2] cycloaddition using perfluoroalkyl azides through Click reaction under Sharpless conditions, and obtained a series of novel perfluoroalkyl-1H,1,2,3-triazol-4-yl substituted quinazolines 4, 5, and 6. All the compounds were screened for antimicrobial activity and identified potential compounds.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Quinazolinas/química , Quinazolinas/farmacologia , Triazóis/química , Anti-Infecciosos/síntese química , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Molecular , Quinazolinas/síntese química , Reprodutibilidade dos Testes , Termodinâmica
16.
J Enzyme Inhib Med Chem ; 24(2): 559-65, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18951276

RESUMO

A versatile and efficient method has been developed for the synthesis of bis(indolyl)methanes by using aluminium triflate (0.5 mol%) as a novel catalyst. Further, some of the synthesized compounds were evaluated for their efficacy as antibacterial and antifungal activities. Most of the compounds have shown moderate to good inhibitory activity.


Assuntos
Antibacterianos/síntese química , Indóis/síntese química , Metano/química , Antibacterianos/farmacologia , Catálise , Indóis/farmacologia , Metano/análogos & derivados , Metano/farmacologia , Testes de Sensibilidade Microbiana
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