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1.
Chemosphere ; 353: 141571, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423148

RESUMO

The treatment of various organic pollutants from industrial wastewater using bio-based materials has gained significant attention owing to their excellent properties such as low-cost, eco-friendly, non-toxic, and biodegradability. In this perspective, casein (Cn), a protein-based biopolymer, was extracted from the cow milk as a low-cost adsorbent, and the adsorption performances were determined for the pristine Cn. The adsorbent was employed for the removal of two different classes of targeted pollutant anionic dyes such as Congo red (CR), Eriochrome Black T (EBT), Eosin Y (EY), and pharmaceutical waste i.e., diclofenac sodium (DS) and displayed better adsorption performances with the maximum adsorption capacity of 85.54, 31.72, 70.42 and 358.42 mg g-1 respectively. The interactions between Cn and pollutants are mainly ascribed to the electrostatic interaction, hydrogen bonding, hydrophobic interaction, and π-π interactions. Furthermore, to validate with realistic application the adsorbent proved with an excellent removal efficiency of 91.43% for fabric whitener i.e., Ujala Supreme®. These obtained results suggest that the Cn could be the potential adsorbent to effectively eliminate toxic pollutants from the aqueous solutions.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Corantes/análise , Diclofenaco , Caseínas , Adsorção , Biopolímeros , Água , Poluentes Químicos da Água/análise , Cinética , Concentração de Íons de Hidrogênio
2.
Biosensors (Basel) ; 13(7)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37504135

RESUMO

Drug delivery systems (DDS) are continuously being explored since humans are facing more numerous complicated diseases than ever before. These systems can preserve the drug's functionality and improve its efficacy until the drug is delivered to a specific site within the body. One of the least used materials for this purpose are metal-organic frameworks (MOFs). MOFs possess many properties, including their high surface area and the possibility for the addition of functional surface moieties, that make them ideal drug delivery vehicles. Such properties can be further improved by combining different materials (such as metals or ligands) and utilizing various synthesis techniques. In this work, the microfluidic technique is used to synthesize Zeolitic Imidazole Framework-67 (ZIF-67) containing cobalt ions as well as its bimetallic variant with cobalt and zinc as ZnZIF-67 to be subsequently loaded with diclofenac sodium and incorporated into sodium alginate beads for sustained drug delivery. This study shows the utilization of a microfluidic approach to synthesize MOF variants. Furthermore, these MOFs were incorporated into a biopolymer (sodium alginate) to produce a reliable DDS which can perform sustained drug releases for up to 6 days (for 90% of the full amount released), whereas MOFs without the biopolymer showed sudden release within the first day.


Assuntos
Estruturas Metalorgânicas , Humanos , Alginatos , Microfluídica , Sistemas de Liberação de Medicamentos , Diclofenaco
3.
J Cardiol ; 79(4): 482-488, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34848117

RESUMO

BACKGROUND: Cardiovascular sequelae of coronavirus disease 2019 (COVID-19) infection have been explored by clinicians and researchers all over the world. OBJECTIVE: The purpose of this study was to evaluate the incidence of atrioventricular block (AV) in patients hospitalized for COVID-19 and its association between in-hospital morbidity and mortality. METHODS: In-hospital electrocardiograms (ECGs) of 438 patients were compared with their prior or baseline ECGs to ascertain the development of new onset AV block. Patients who developed new AV blocks were then followed at 30 and 90 days post-discharge to check for resolution of AV block. Demographic characteristics, clinical characteristics, and complications during their hospital stay were evaluated. Major complications including respiratory failure requiring oxygen supplementation and mechanical ventilation, sepsis, deep vein thrombosis, elevated troponins, hospital and intensive care unit (ICU) length of stay, as well as death were compared between those who developed new onset AV blocks and those who did not. RESULTS: Based on our single center study, the incidence of new onset AV blocks among patients admitted for COVID-19 during the study period was 5.5 cases per 100 patients. New onset AV blocks were not associated with longer hospital and ICU length of stay, increased intubation rates, or increased mortality. CONCLUSION: Although the development of a new onset AV block is most likely multifactorial and not solely due to COVID-19, it is still important for clinicians to be mindful about the possibility of developing symptomatic bradycardia and life-threatening arrhythmias in patients admitted for COVID-19. This can be achieved by appropriate rhythm monitoring in-patient but the need for a cardiac event monitor upon discharge is unlikely to be necessary. Careful history taking, including family and drug use history is also of great importance as emerging drug therapies for COVID-19 have potential arrhythmogenic effects.


Assuntos
Bloqueio Atrioventricular , COVID-19 , Assistência ao Convalescente , Bloqueio Atrioventricular/epidemiologia , Bloqueio Atrioventricular/etiologia , Mortalidade Hospitalar , Humanos , Incidência , Alta do Paciente , SARS-CoV-2
4.
NPJ Sci Food ; 5(1): 26, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471114

RESUMO

We describe the design of peptides with properties like thermostability, pH stability, and antibacterial activity against a few bacterial food pathogens. Insights obtained from classical structure-function analysis of natural peptides and their mutants through antimicrobial and enzymatic assays are used to rationally develop a set of peptides. pH and thermostability assays were performed to demonstrate robust antimicrobial activity post-treatment with high temperatures and at wide pH ranges. We have also investigated the mode of action of these hyperstable peptides using membrane permeability assays, electron microscopy, and molecular dynamics simulations. Notably, through mutational studies, we show that these peptides elicit their antibacterial action via both membrane destabilization and inhibition of intracellular trypsin-the two functions attributable to separate peptide segments. Finally, toxicity studies and food preservation assays demonstrate the safety and efficacy of the designed peptides for food preservation. Overall, the study provides a general 'blueprint' for the development of stable antimicrobial peptides (AMPs). Insights obtained from this work may also be combined with combinatorial methods in high-throughput studies for future development of antimicrobials for various applications.

5.
Protein Expr Purif ; 177: 105760, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33002609

RESUMO

Resistance to antibiotics is a serious concern to treat infectious diseases and also, for food preservation. Existing antibiotics generally inhibit enzymes participating in key bacterial processes, such as formation of cell wall, replication, transcription and translation. However, bacteria have rapidly evolved new mechanisms to combat these antibiotics and it hence becomes indispensable to identify newer targets and identify/design inhibitors against them. Another concern is that most antibiotics are broad spectrum; they largely bind and inhibit the active site of the target enzyme. Rel proteins, which synthesize (and hydrolyze) (p)ppGpp in response to a variety of stress encountered by bacteria, is a profitable target owing to its distinct absence in humans and an intricate regulation of the catalytic activities. Inactivation of (p)ppGpp synthesis by Rel, disables bacterial survival in Mycobacterium tuberculosis and Staphylococcus aureus, while inactivating the hydrolysis activity was lethal. The poor MIC values of the currently known Rel inhibitors present a distinct opportunity to develop better inhibitors and warrants a detailed structural characterization and understanding of the complex regulation in Rel proteins. It will open new avenues for the design of effective, species-specific inhibitors. In an attempt to identify unique sites for inhibitor design using structure-based approaches, we initiate a study of Rel homologues from four different pathogenic bacteria, in order to compare their attributes with well characterized Rel homologues. Here, we present cloning, over-expression, purification and preliminary characterization of these four homologues; and suggest similarities and differences that can be exploited for inhibitor design.


Assuntos
Guanosina Pentafosfato/química , Ligases/química , Pirofosfatases/química , Sequência de Aminoácidos , Sítios de Ligação , Clonagem Molecular , Biologia Computacional/métodos , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Guanosina Pentafosfato/metabolismo , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Cinética , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/metabolismo , Klebsiella pneumoniae/patogenicidade , Ligases/genética , Ligases/metabolismo , Listeria monocytogenes/genética , Listeria monocytogenes/metabolismo , Listeria monocytogenes/patogenicidade , Modelos Moleculares , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Mycobacterium tuberculosis/patogenicidade , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/patogenicidade , Pirofosfatases/genética , Pirofosfatases/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Shigella flexneri/genética , Shigella flexneri/metabolismo , Shigella flexneri/patogenicidade , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Staphylococcus aureus/patogenicidade , Homologia Estrutural de Proteína , Especificidade por Substrato , Termodinâmica
6.
Environ Sci Pollut Res Int ; 28(9): 10633-10641, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33099729

RESUMO

A heterogeneous catalyst comprising Keggin type polyoxometalate, silicotungstic acid (SiW12), and MCM-22 was synthesized using wet impregnation method and characterized by acidity measurement, BET, FT-IR, XRD, and SEM. Their catalytic activity was evaluated for the degradation of cationic organic dyes like methylene blue (MB), crystal violet (CV), and an azo dye Chryosidine Y (CY) in an aqueous solution. The experimental parameters such as catalyst amount, initial dye concentration, and contact time were studied for the degradation of dyes, and it was found that the cationic dyes like methylene blue and crystal violet show better activity as compared to azo dye Chryosidine Y. This may be attributed to better electrostatic interaction of these cationic dyes with the residual negative surface charge of the catalyst, due to presence of SiW12 ion as it is rich in surface oxygens and surface hydroxyl groups. The control experimental results showed that the presence of SiW12 at the surface of MCM-22 promoted the degradation reactions, and presence of multiple W-O bonds in polyoxometalate also played a key role in this reaction. The catalyst exhibits recycling ability without any significant loss in activity up to four cycles.


Assuntos
Corantes , Silicatos , Catálise , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos de Tungstênio
7.
Cardiol Res ; 9(5): 307-313, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30344829

RESUMO

Cardiac intimal sarcomas are extremely rare, remarkably aggressive and least reported type of primary malignant tumors of the heart. Cardiac intimal sarcomas are encountered more commonly in the large arterial blood vessels including pulmonary artery and aorta, and are extremely rare in the heart. The mainstay of treatment is achievement of tumor-free margins with surgical resection, which is associated with improved survival. Here, we report a 66-year-old female with primary cardiac intimal sarcoma presented with functional mitral stenosis and heart failure. This case report emphasizes common presentation of a rare disease, and the significance of early diagnosis and timely intervention.

8.
Cardiol Res ; 9(3): 183-185, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29904457

RESUMO

Renal cell carcinoma (RCC) is an aggressive and lethal tumor that has a high frequency of metastatic spread to unpredictable sites. One quarter of patients have either distant metastases or significant local-regional disease with atypical symptoms on presentation. We present a 41-year-old patient with symptoms of right heart failure and was found to have metastatic renal cell carcinoma with enhancing tumor from left renal vein up to right atrium.

9.
Clin Med Insights Cardiol ; 11: 1179546817710026, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28579858

RESUMO

BACKGROUND: This study was designed to assess the clinical impact and cost-benefit of cardiovascular magnetic resonance imaging (CMR). In the face of current health care cost concerns, cardiac imaging modalities have come under focused review. Data related to CMR clinical impact and cost-benefit are lacking. METHODS AND RESULTS: Retrospective review of 361 consecutive patients (pts) who underwent CMR exams was conducted. Indications for CMR were tabulated for appropriateness criteria. Components of the CMR exam were identified along with evidence of clinical impact. The cost of each CMR exam was ascertained along with cost savings attributable to the CMR exam for calculation of an incremental cost-effectiveness ratio. A total of 354 of 361 pts (98%) had diagnostic quality studies. Of the 361 pts, 350 (97%) had at least 1 published Appropriateness Criterion for CMR. A significant clinical impact attributable to CMR exam results was observed in 256 of 361 pts (71%). The CMR exam resulted in a new diagnosis in 69 of 361 (27%) pts. Cardiovascular magnetic resonance imaging results avoided invasive procedures in 38 (11%) pts and prevented additional diagnostic testing in 26 (7%) pts. Comparison of health care savings using CMR as opposed to current standards of care showed a net cost savings of $833 037, ie, per patient cost savings of $2308. CONCLUSIONS: Cardiovascular magnetic resonance imaging provides diagnostic image quality in >98% of cases. Cardiovascular magnetic resonance imaging findings have documentable clinical impact on patient management in 71% of pts undergoing the exam, in a cost beneficial manner.

10.
Heart Asia ; 5(1): 80, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-27326086
11.
Org Biomol Chem ; 9(12): 4570-9, 2011 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-21537512

RESUMO

A novel harringtonolide-inspired scaffold containing a cycloheptatriene ring and two fused cyclopentane rings has been synthesised from simple starting materials. The scaffold, containing a similar substitution pattern and relative stereochemistry to the complex diterpenoid, has been enumerated into a small library of derivatives. One of these library members has been converted into a sub-library of substituted triazoles using copper-catalysed azide-alkyne cycloaddition (click) chemistry. The scaffold may be useful in drug discovery or in the preparation of additional molecular probes for chemical biology.


Assuntos
Antineoplásicos Fitogênicos/síntese química , Química Farmacêutica , Harringtoninas/síntese química , Sondas Moleculares/síntese química , Bibliotecas de Moléculas Pequenas/síntese química , Taxaceae/química , Triazóis/síntese química , Antineoplásicos Fitogênicos/análise , Azidas/química , Catálise , Química Click , Cobre/química , Ciclopentanos/química , Descoberta de Drogas , Harringtoninas/análise , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Sondas Moleculares/análise , Neoplasias/tratamento farmacológico , Plantas Medicinais/química , Bibliotecas de Moléculas Pequenas/análise , Estereoisomerismo , Triazóis/análise
13.
Heart Lung Circ ; 16(6): 423-7, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17611152

RESUMO

BACKGROUND: Patients with the antiphospholipid syndrome (APLS) have severe involvement of the cardiovascular apparatus and often need surgical interventions to correct these manifestations. Few studies that have looked at the outcomes of cardiothoracic surgeries in APLS patients have reported high rates of perioperative mortality and thromboembolic events. OBJECTIVE: Our goal was to examine the outcomes of adult APLS patients undergoing coronary artery bypass surgery (CABG) and/or valvular surgery. We also wanted to determine whether aggressive anticoagulation therapy could prevent life threatening thromboembolic complications in these patients. METHODS: We retrospectively reviewed medical records of nine patients with primary APLS undergoing cardiothoracic surgery between 1985 and 2005 at our institution. Patient demographics, operative procedures and one-year clinical outcomes were obtained. RESULTS: Forty-five percent of our patients had more than three cardiovascular risk factors other than APLS. There were no mortalities in our case series. However, 89% of our patients developed major complications. Despite aggressive anticoagulation, 37.5% developed thromboembolic events including cerebrovascular accidents, myocardial infarctions and vena caval thrombosis. Other complications included heparin-induced thrombocytopenia, redo of CABG surgery and sepsis. CONCLUSION: Despite aggressive anticoagulation and lack of significant pre-operative co-morbidities, APLS patients undergoing cardiothoracic surgery appear to have high rates of post-operative clinical events.


Assuntos
Síndrome Antifosfolipídica/cirurgia , Doença da Artéria Coronariana/cirurgia , Doenças das Valvas Cardíacas/cirurgia , Complicações Pós-Operatórias , Adulto , Idoso , Anticoagulantes/uso terapêutico , Síndrome Antifosfolipídica/complicações , Arritmias Cardíacas/etiologia , Constrição Patológica/etiologia , Ponte de Artéria Coronária , Doença da Artéria Coronariana/etiologia , Feminino , Doenças das Valvas Cardíacas/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Trombocitopenia/induzido quimicamente , Tromboembolia/etiologia , Tromboembolia/prevenção & controle
15.
Bioorg Med Chem ; 14(9): 3069-80, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16406644

RESUMO

A series of 2,6-disubstituted and 2,5,6-trisubstituted imidazo[2,1-b][1,3,4]thiadiazoles were synthesized, the structures of the compounds were elucidated and screened for antitubercular activity against Mycobacterium tuberculosis H37Rv using the BACTEC 460 radiometric system, antibacterial activity against Escherichia coli and Bacillus cirrhosis, and antifungal activity against Aspergillus niger and Penicillium wortmanni. Among the tested compounds 2-(2-furyl)-6-phenylimidazo[2,1-b][1,3,4] thiadiazole-5-carbaldehyde (6c) and (2-cyclohexyl-6-phenylimidazo[2,1-b][1,3,4]thiadiazol-5-yl)methanol (7a) have shown the highest (100%) inhibitory activity. Compounds 6a, 6b, 7c, and 8a exhibited moderate antitubercular activity with percentage inhibition 36, 30, 15, and 20, respectively, at a MIC of >6.25 microg/ml.


Assuntos
Antituberculosos/síntese química , Antituberculosos/farmacologia , Tiadiazóis/química , Tiadiazóis/farmacologia , Antituberculosos/química , Aspergillus/efeitos dos fármacos , Bacillus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Estrutura Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Penicillium/efeitos dos fármacos , Relação Estrutura-Atividade , Tiadiazóis/síntese química
16.
Indian J Gastroenterol ; 22(6): 209-11, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15030030

RESUMO

OBJECTIVE: Gastric carcinoids (GC) are rare tumors. Recent studies have reported a higher frequency of GC, with these constituting 10%-30% of all carcinoid tumors. We have observed GC more frequently at our institute in recent years than in the past. METHODS: Endoscopy reports from January 1997 to June 2003 were reviewed to identify patients with GC. For these patients, biopsy specimens were reviewed and details of clinical features were extracted from case records. RESULTS: Seventeen patients with GC (aged 27 to 76 years; 11 men) were identified; in comparison, there had been only 8 cases in the previous 16 years. Of these, 14 patients had multiple tumors; these were located in the fundus (n = 6), fundus and proximal body (4), and body (4) of the stomach. Three patients had solitary tumors in the antrum. The tumor size ranged from pinhead to 4 cm. Etiologically, 13 patients had type 1 GC (associated with chronic atrophic gastritis type A), one had type 2 GC (associated with Zollinger-Ellison syndrome; multiple endocrine neoplasia 1) and three had type 3 GC (sporadic). Treatment included total gastrectomy (2), distal gastrectomy (2), tumor excision (1), endoscopic polypectomy (3), and vitamin B12 supplementation with surveillance (9). CONCLUSION: Our data show an increase in diagnosis of GC, similar to reports from Western countries. The rise is in the proportion of GC associated with atrophic gastritis. Whether this reflects a higher frequency of detection due to more endoscopic biopsy sampling or due to some other reason needs investigation.


Assuntos
Tumor Carcinoide/epidemiologia , Neoplasias Gástricas/epidemiologia , Adulto , Idoso , Tumor Carcinoide/diagnóstico , Tumor Carcinoide/cirurgia , Feminino , Gastrectomia , Gastroscopia , Humanos , Incidência , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/cirurgia
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