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1.
Phys Chem Chem Phys ; 24(34): 20152-20163, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35993971

RESUMO

Structural phase transitions drive several unconventional phenomena including some illustrious ferroic attributes which are relevant for technological advancements. On this note, we have investigated the ferroelastic structural transition of perovskite-type trigonal Ba2ZnTeO6 across Tc ∼ 150 K. With the help of Raman spectroscopy and density-functional theory (DFT)-based calculations, we report new intriguing observations associated with the phase transition in Ba2ZnTeO6. We observed the presence of a central peak (quasi-elastic Rayleigh profile), huge softening in the soft mode, hysteretic phonon behavior, and signatures of coexistent phases. The existence of a central peak in Ba2ZnTeO6 is manifested by a sharp rise in the intensity of the Rayleigh profile concomitant with the huge damping (or softening) of the soft mode (at ∼31 cm-1) near Tc, shedding light on the lattice dynamics during the phase transition. This is further corroborated by our phonon calculations that show that the soft mode (Eg) in the high-symmetry structure involving TeO6 octahedral rotation (with Ba and Zn translation) condenses into Ag and Bg modes in the C2/m low-symmetry phase. While most of the phonon bands split below Tc confirming the phase transition, we observed thermal hysteretic behavior of phonon modes, which signifies the first-order nature of the transition and the presence of coexisting phases as corroborated by our temperature-dependent X-ray diffraction and specific heat measurements.

2.
Allergy ; 73(10): 2033-2045, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29729200

RESUMO

BACKGROUND: Airway epithelial injury is a crucial component of acute and severe asthma pathogenesis and a promising target for treatment of refractory asthma. However, the underlying mechanism of epithelial injury remains poorly explored. Although high levels of polyamines, mainly spermine, have been found in asthma and comorbidity, their role in airway epithelial injury and the cause of their altered levels in asthma have not been explored. METHODS: We measured key polyamine metabolic enzymes in lung samples from normal and asthmatic subjects and in mice with OVA-induced allergic airway inflammation (AAI). Polyamine metabolism was modulated using pharmacologic/genetic modulators. Epithelial stress and apoptosis were measured by TSLP levels and TUNEL assay, respectively. RESULTS: We found loss of the polyamine catabolic enzymes spermidine/spermine-N (1)-acetyltransferase-1 (SAT1) and spermine oxidase (SMOX) predominantly in bronchial epithelial cells (BECs) of human asthmatic lung samples and mice with AAI. In naïve mice, SAT1 or SMOX knockdown led to airway hyper-responsiveness, remodeling, and BEC apoptosis. Conversely, in mice with AAI, overexpression of either SAT1 or SMOX alleviated asthmatic features and reduced TSLP levels and BEC apoptosis. Similarly, while pharmacological induction of SAT1 and SMOX using the polyamine analogue bis(ethyl)norspermine (BENSPM) alleviated asthmatic features with reduced TSLP levels and BEC apoptosis, pharmacological inhibition of these enzymes using BERENIL or MDL72527, respectively, worsened them. Spermine accumulation in lungs correlated with BEC apoptosis, and spermine treatment caused apoptosis of human BEAS-2B cells in vitro. CONCLUSIONS: Spermine induces BEC injury. Induction of polyamine catabolism may represent a novel therapeutic approach for asthma via reversing BEC stress.


Assuntos
Asma/metabolismo , Epitélio/lesões , Poliaminas/metabolismo , Sistema Respiratório/patologia , Espermina/metabolismo , Animais , Apoptose , Asma/etiologia , Células Epiteliais/química , Células Epiteliais/enzimologia , Células Epiteliais/patologia , Humanos , Pulmão/enzimologia , Camundongos , Espermina/efeitos adversos
3.
Niger J Clin Pract ; 20(7): 905-909, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28791988

RESUMO

Clinical reports of symptomatic intraocular metastasis as the initial presentation of lung cancer are rare. We report the case of a 49-year-old female patient who presented with loss of vision due to choroidal metastases as the initial manifestation of her disseminated lung cancer. This particular patient was referred to us from ophthalmology department as a case of choroidal metastases from unknown primary. Detailed evaluation at our department helped detect the primary to be a nonsmall cell carcinoma of the right lung, which had multiple distant metastases.


Assuntos
Adenocarcinoma/secundário , Neoplasias da Coroide/patologia , Neoplasias da Coroide/secundário , Neoplasias Pulmonares/patologia , Pulmão/diagnóstico por imagem , Tórax/diagnóstico por imagem , Transtornos da Visão/diagnóstico por imagem , Baixa Visão/diagnóstico por imagem , Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Angiofluoresceinografia , Humanos , Neoplasias Pulmonares/terapia , Pessoa de Meia-Idade , Metástase Neoplásica , Tomografia Computadorizada por Raios X , Ultrassonografia , Transtornos da Visão/etiologia , Baixa Visão/etiologia
4.
Eur J Clin Microbiol Infect Dis ; 35(9): 1449-54, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27250633

RESUMO

Plasmid-mediated AmpC (pAmpC) and ESBL co-production was detected in Escherichia coli a major etiologic agent of urinary tract infection. Isolates resistant to cefoxitin by CLSI methodology were tested for pAmpC beta-lactamase using phenylboronic acid and ESBLs by combined disk diffusion method. pAmpC/ESBL genes were characterized by PCR and sequencing. Transconjugation experiments were done to study the transfer of pAmpC and ESBL production from clinical isolates as donor to E. coli J53 AziR as recipient. Incompatibility groups of transmissible plasmids were classified by PCR-based replicon typing (PBRT). Among 148 urine culture positive isolates, E. coli was reported in 39.86 % (59/148), with 93.22 % (55/59) of cefoxitin resistance. pAmpC production was detected in 25, with varied distribution of blaCMY-2 and blaDHA-1type genes alone (n = 13 and 7 respectively) or in combination (n = 5). ESBL co-production was observed in 88 % (22/25) of pAmpC producing isolates with predominance of blaTEM (n = 20). Twenty-three transconjugants showed transmission of pAmpC-and ESBL-resistant genes with co-carriage of blaCMY-2 and blaTEM (n = 15) in plasmids of IncF type (n = 9) being predominant, followed by IncI1 (n = 4) and IncH1 (n = 2) in combination. All clinical isolates were clonally diverse. Resistance against different beta-lactams in uropathogenic E. coli has been an emerging concern in resource- poor countries such as India. Knowledge on the occurrence of AmpC beta-lactamases and ESBL amongst this pathogen and its transmission dynamics may aid in hospital infection control.


Assuntos
Antibacterianos/farmacologia , Cefoxitina/farmacologia , Escherichia coli Uropatogênica/efeitos dos fármacos , Escherichia coli Uropatogênica/enzimologia , Resistência beta-Lactâmica , beta-Lactamases/metabolismo , Conjugação Genética , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Infecções por Escherichia coli/microbiologia , Transferência Genética Horizontal , Variação Genética , Genótipo , Humanos , Índia , Tipagem Molecular , Plasmídeos/análise , Plasmídeos/classificação , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/genética , Escherichia coli Uropatogênica/isolamento & purificação , beta-Lactamases/genética
5.
J Fish Dis ; 39(1): 1-11, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25272249

RESUMO

Flavobacterium psychrophilum is the causative agent of bacterial coldwater disease (BCWD), which has a major impact on salmonid aquaculture globally. An Enterobacter species, C6-6, isolated from the gut of rainbow trout, Oncorhynchus mykiss (Walbaum), has been identified as a potential probiotic species providing protection against BCWD. This study examined the effects of alginate microencapsulation on the protective efficacy of C6-6 against BCWD in vivo when administered to rainbow trout fry orally or by intraperitoneal (IP) injection. Viable C6-6 bacteria were microencapsulated successfully, and this process (microencapsulation) did not significantly deteriorate its protective properties as compared to the administration of non-microencapsulated C6-6 bacteria. Both oral and IP delivery of C6-6 achieved significantly better protection than control treatments that did not contain C6-6 bacteria. The highest relative percent survival (RPS) resulted from IP delivery (71.4%) and was significantly greater than the highest oral RPS (38.6%). Successful intestinal colonization was not critical to protective effects of C6-6. The study showed that C6-6 administration, with or without encapsulation, was a viable choice for protecting fry from BCWD especially when administered intraperitoneally.


Assuntos
Composição de Medicamentos/veterinária , Doenças dos Peixes/prevenção & controle , Infecções por Flavobacteriaceae/veterinária , Flavobacterium/fisiologia , Oncorhynchus mykiss , Probióticos/administração & dosagem , Administração Oral , Alginatos , Animais , Doenças dos Peixes/microbiologia , Pesqueiros , Infecções por Flavobacteriaceae/prevenção & controle , Flavobacterium/patogenicidade , Injeções Intraperitoneais/veterinária , Virulência
6.
SAR QSAR Environ Res ; 35(2): 157-179, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38346125

RESUMO

A Disintegrin and Metalloproteinase 17 (ADAM17), a Zn2+-dependent metalloenzyme of the adamalysin family of the metzincin superfamily, is associated with various pathophysiological conditions including rheumatoid arthritis and cancer. However, no specific inhibitors have been marketed yet for ADAM17-related disorders. In this study, 94 quinolinyl methoxyphenyl sulphonyl-based hydroxamates as ADAM17 inhibitors were subjected to classification-based molecular modelling and binding pattern analysis to identify the significant structural attributes contributing to ADAM17 inhibition. The statistically validated classification-based models identified the importance of the P1' substituents such as the quinolinyl methoxyphenyl sulphonyl group of these compounds for occupying the S1' - S3' pocket of the enzyme. The quinolinyl function of these compounds was found to explore stable binding of the P1' substituents at the S1' - S3' pocket whereas the importance of the sulphonyl and the orientation of the P1' moiety also revealed stable binding. Based on the outcomes of the current study, four novel compounds of different classes were designed as promising ADAM17 inhibitors. These findings regarding the crucial structural aspects and binding patterns of ADAM17 inhibitors will aid the design and discovery of novel and effective ADAM17 inhibitors for therapeutic advancements of related diseases.


Assuntos
Ácidos Hidroxâmicos , Relação Quantitativa Estrutura-Atividade , Proteína ADAM17 , Modelos Moleculares , Ácidos Hidroxâmicos/química
7.
SAR QSAR Environ Res ; 35(5): 367-389, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38757181

RESUMO

Histone deacetylase 3 (HDAC3), a Zn2+-dependent class I HDACs, contributes to numerous disorders such as neurodegenerative disorders, diabetes, cardiovascular disease, kidney disease and several types of cancers. Therefore, the development of novel and selective HDAC3 inhibitors might be promising to combat such diseases. Here, different classification-based molecular modelling studies such as Bayesian classification, recursive partitioning (RP), SARpy and linear discriminant analysis (LDA) were conducted on a set of HDAC3 inhibitors to pinpoint essential structural requirements contributing to HDAC3 inhibition followed by molecular docking study and molecular dynamics (MD) simulation analyses. The current study revealed the importance of hydroxamate function for Zn2+ chelation as well as hydrogen bonding interaction with Tyr298 residue. The importance of hydroxamate function for higher HDAC3 inhibition was noticed in the case of Bayesian classification, recursive partitioning and SARpy models. Also, the importance of substituted thiazole ring was revealed, whereas the presence of linear alkyl groups with carboxylic acid function, any type of ester function, benzodiazepine moiety and methoxy group in the molecular structure can be detrimental to HDAC3 inhibition. Therefore, this study can aid in the design and discovery of effective novel HDAC3 inhibitors in the future.


Assuntos
Teorema de Bayes , Inibidores de Histona Desacetilases , Histona Desacetilases , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Relação Quantitativa Estrutura-Atividade , Histona Desacetilases/química , Histona Desacetilases/metabolismo , Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/farmacologia , Análise Discriminante , Estrutura Molecular
8.
Wirel Pers Commun ; 130(3): 1861-1884, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37206635

RESUMO

Wireless Body Area Network (WBAN) is an emerging and promising specialized area in Wireless networks that deals with crucial health-related datasets. Unlike other wireless networks, as this type of network deals with medical facts, losing it is fatal. WBAN is a highly constrained network. Reducing energy consumption and enhancing lifetime are the two most important challenges of WBANs. One way to achieve these is by deploying relay nodes optimally in WBANs. Generally, a relay node is placed at the midpoint of the line joining the source and the destination (D) nodes. We show that such simplistic deployment of the relay nodes is not the optimal deployment, which can hamper the overall lifetime of WBANs. In this paper, we have investigated the best location to deploy a relay node on a human body. We assume that an adaptive decode and forward relay node (R) can move linearly between the source (S) and the destination (D) nodes. Moreover, the assumption is that a relay node can be deployed linearly and that the body part of a human is a flat surface and hard. We have investigated the most energy-efficient data payload size based on the optimally placed relay location. The impact of such a deployment on different system parameters, such as distance (d), payload (L), modulation scheme, specific absorption rate, and an end to end outage (O) are examined as well. It is observed that in every aspect optimal deployment of the relay node performs an important role to enhance the lifetime of wireless body area networks. Sometimes linear relay deployment is very difficult to implement, especially on the different body parts of the human body. To address these issues, we have examined the optimal region for the relay node based on a 3D non-linear system model. The paper provides guidance for both linear and non-linear relay deployment along with the optimal data payload size under various circumstances and also considered the impact of specific absorption rates on the human body.

9.
SAR QSAR Environ Res ; 34(4): 299-319, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37170840

RESUMO

Among various matrix metalloproteinases (MMPs), overexpression of MMP9 has been established as a key player in a variety of cancers. Therefore, MMP9 has emerged as a promising biomolecule that may be targeted to design potent inhibitors as novel anticancer therapeutics. In this study, a large database containing 1,123 drug-like MMP-9 inhibitors was considered for robust classification-dependent fragment-based QSAR study through SARpy, Bayesian classification, and recursive partitioning analyses and were validated by both internal and external validation techniques. In a nutshell, all these classification-dependent techniques revealed some common structural alerts and sub-structural fingerprints responsible for modulating MMP-9 inhibition. These observations are in agreement with the interactions obtained from the ligand-bound co-crystal structures of MMP-9 justifying the robustness of the current study. Finally, based on these crucial structural fragments, some new lead compounds were designed and further validated by the binding mode of interaction analysis. Therefore, these findings may be beneficial in designing novel and potential MMP-9 inhibitors in the future as a weapon to combat several cancers.


Assuntos
Metaloproteinase 9 da Matriz , Inibidores de Metaloproteinases de Matriz , Teorema de Bayes , Metaloproteinase 9 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/química , Inibidores de Metaloproteinases de Matriz/farmacologia , Relação Quantitativa Estrutura-Atividade
10.
SAR QSAR Environ Res ; 34(10): 805-830, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37850742

RESUMO

MMP-2 is potentially contributing to several cancer progressions including leukaemias. Therefore, considering MMP-2 as a promising target, novel anticancer compounds may be designed. Here, 32 in-house arylsulfonyl L-(+) glutamines were subjected to various structure-based computational modelling approaches to recognize crucial structural attributes along with the spatial orientation for higher MMP-2 inhibition. Again, the docking-based 2D-QSAR study revealed that the Coulomb energy conferred by Tyr142 and total interaction energy conferred by Ala84 was crucial for MMP-2 inhibition. Importantly, the docking-dependent CoMFA and CoMSIA study revealed the importance of favourable steric, electrostatic, and hydrophobic substituents at the terminal phenyl ring. The MD simulation study revealed a lower fluctuation in the RMSD, RMSF, and Rg values indicating stable binding interactions of MMP-2 and these molecules. Moreover, the residual hydrogen bond and their interaction analysis disclosed crucial amino acid residues responsible for forming potential hydrogen bonding for higher MMP-2 inhibition. The results can effectively aid in the design and discovery of promising small-molecule drug-like MMP-2 inhibitors with greater anticancer potential in the future.


Assuntos
Antineoplásicos , Glutamina , Metaloproteinase 2 da Matriz , Inibidores de Metaloproteinases de Matriz , Antineoplásicos/química , Antineoplásicos/farmacologia , Simulação por Computador , Glutamina/química , Glutamina/farmacologia , Inibidores de Metaloproteinases de Matriz/química , Inibidores de Metaloproteinases de Matriz/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Relação Quantitativa Estrutura-Atividade
11.
J Biomol Struct Dyn ; 41(20): 11274-11285, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36562209

RESUMO

Resistance to antibiotics/antibacterials/antifungals in pathogenic microbes has been developing over the past few decades and has recently become a commonplace public-health peril. Thus, alternative nontoxic potent antibiotic agents are covertly needed to control antibiotic-resistant outbreaks. In an effort to combat the challenges posed by the co-occurrence of multidrug resistance, two terpyridine ligands 4'-(4-N,N'-dimethylaminophenyl)-2,2':6',2″-terpyridine (L1) and 4'-(4-tolyl)-2,2':6',2″-terpyridine (L2) have been designed, prepared and confirmed their structure by spectral studies. Thereafter, antimicrobial assay was performed against gram positive and negative bacterial strains along with fungal strains. Both compounds L1 and L2 exhibited remarkable inhibitory activities against bacteria, Escherichia coli and Staphylococcus aureus at MIC values 6.25 and 3.125 µg/ml, respectively. In addition, in silico molecular docking studies were ascertained with bacterial DNA gyrase and fungal demethylase. Furthermore, both L1 and L2 could bind Bovine Serum Albumin (BSA) protein and binding interaction has been studied with the help of UV-Visible and fluorescence spectroscopy. While fluorescence of BSA unperturbed in the presence of L2, an addition of L1 to the solution of BSA resulted significant quenching. The binding constant calculations at different temperature confirmed that the fluorescence quenching between BSA and L1 is predominantly static in nature. The toxicity of L1 and L2 was checked using Drosophila melanogaster. The toxicity analysis suggest both the dyes are non-cytotoxic in nature.Communicated by Ramaswamy H. Sarma.


Assuntos
Antifúngicos , Drosophila melanogaster , Animais , Simulação de Acoplamento Molecular , Antifúngicos/farmacologia , Drosophila melanogaster/metabolismo , Espectrometria de Fluorescência/métodos , Antibacterianos/farmacologia , Antibacterianos/química , Soroalbumina Bovina/química , Ligantes , Testes de Sensibilidade Microbiana
12.
Minerva Med ; 103(6): 431-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23229365

RESUMO

Treatment of acute ST-elevation myocardial infarction (STEMI) has rapidly evolved with many advances made in the past decade. Percutaneous coronary intervention is the preferred strategy when available, although there remains a role for thrombolytic therapy, with prompt reperfusion as the primary goal. With regards to antithrombotic therapy, bivalirudin now has a significant role in STEMI care with improved outcomes over unfractionated heparin plus GP IIb/IIIa inhibitors. Dual antiplatelet therapy has become a mainstay of treatment with combination of aspirin and clopidogrel, as well as an expanding role of more potent novel agents, prasugrel and ticagrelor. In primary PCI in STEMI, coronary stents are now being used routinely, although short-term and long-term outcomes of drug-eluting stents (DES) versus bare metal stents (BMS) continue to be studied. Recent meta-analyses have examined the trade-off of lower rates of in-stent restenosis and need for target vessel revascularization with DES versus the potential increase in the risk of stent thrombosis and need for longer course of dual antiplatelet therapy. This review will discuss the current STEMI guidelines and strategies, recent advances in pharmacotherapy, and data on stent selection.


Assuntos
Infarto do Miocárdio/terapia , Angioplastia Coronária com Balão , Stents Farmacológicos , Humanos , Reperfusão Miocárdica/métodos , Inibidores da Agregação Plaquetária/uso terapêutico , Guias de Prática Clínica como Assunto , Stents , Terapia Trombolítica/métodos
13.
J Environ Sci Health B ; 47(3): 205-11, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22375592

RESUMO

A study was conducted to evaluate the changes in total calcium and sulphur and some heavy metal (Zn, Cu, and Pb) concentration of different organic wastes affected by liming and microorganism inoculation. Vermicomposting was an effective technology for disposal of organic substrates like municipal solid wastes (MSW), possessing comparatively higher concentration of heavy metals. The addition of lime in initial organic substrates significantly (P ≤ 0.05) increased total calcium and total sulphur content of vermicomposts. Inoculation of microorganisms significantly (P ≤ 0.05) reduced the heavy metal content of final products as compared to control. Fungal strains were comparatively more effective in detoxification of heavy metals than B. polymyxa.


Assuntos
Cálcio/metabolismo , Metais Pesados/metabolismo , Oligoquetos/metabolismo , Eliminação de Resíduos/métodos , Solo/química , Enxofre/metabolismo , Animais , Bacillus/metabolismo , Biodegradação Ambiental , Cálcio/análise , Carbonato de Cálcio , Cobre/análise , Cobre/metabolismo , Concentração de Íons de Hidrogênio , Chumbo/análise , Chumbo/metabolismo , Metais Pesados/análise , Phanerochaete/metabolismo , Microbiologia do Solo , Enxofre/análise , Trichoderma/metabolismo , Resíduos , Zinco/análise , Zinco/metabolismo
14.
Parasite Immunol ; 33(11): 632-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21729107

RESUMO

Absence of an effective Th-1 response has been demonstrated as a major cause for the disease pathology among patients with visceral leishmaniasis (VL). Defining strategies to prevent the development of Th-2 response and/or initiate/activate effective Th-1 response may be of help to reduce the growing incidence of drug unresponsiveness. Adenosine, which is considered as an endogenous anti-inflammatory agent is generated in injured/inflamed tissues by the enzymatic catabolism of adenosine triphosphate (ATP), and it suppresses inflammatory responses of essentially all immune cells. The extracellular adenosine-producing pathway comprises two major enzymes CD39 (ATP → ADP → AMP) and CD73 (AMP → Adenosine). In contrast, the adenosine-degrading pathway contains only one major enzyme adenosine deaminase (ADA). Our study shows high concentration of adenosine in diseased condition, varying expression of enzyme involved in adenosine-producing (CD73↓) and adenosine-degrading (ADA↑) pathways. These are less studied in infections like VL but are very important in terms of endogenous regulation of immune response among patients.


Assuntos
5'-Nucleotidase/sangue , Adenosina Desaminase/sangue , Adenosina/sangue , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/metabolismo , 5'-Nucleotidase/metabolismo , Adenosina/metabolismo , Adenosina Desaminase/metabolismo , Trifosfato de Adenosina/metabolismo , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Leishmania donovani/imunologia , Masculino , Pessoa de Meia-Idade , Células Th1/imunologia , Células Th2/imunologia
15.
Pharmazie ; 66(11): 843-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22204129

RESUMO

The aim of the present study was to prepare a colon targeted pellet formulation of secnidazole and to evaluate the formulation in vitro and in vivo by a gamma scintigraphy method. Pectin/ethyl cellulose in different ratios and in different coating labels with plasticizer was used to prepare secnidazole pellets by a powder layering technique. The formulations were tagged with 99mTC-DTPA, a tracer in gamma scintigraphy to evaluate its transit behavior in rabbits. Morphology and compatibility were studied using Scanning Electron Microscopy, IR spectroscopy and Differential Scanning Calorimetry were used for the characterization of prepared pellets. The in-vitro study suggested that pectin (59%) esterification and ethyl cellulose 45cps at 20% coating label led to an optimum bacterial enzyme dependent released behavior. The optimized formulation was subjected to an in-vivo transit study. Scintigraphy images clearly indicated that the formulation can delay the drug release prior to the colon. The average time of gastric emptying and colon arrival was 57 min and 6.08 h, respectively. The coated pellets prepared by powder layering technology successfully released drug in the colon indicating that site specificity has been achieved with pectin 59% esterification and ethyl cellulose 45 cps at 1:2 ratio with 20% coating label.


Assuntos
Antiprotozoários/administração & dosagem , Celulose/análogos & derivados , Colo/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Excipientes/química , Metronidazol/análogos & derivados , Pectinas/química , Animais , Antiprotozoários/síntese química , Varredura Diferencial de Calorimetria , Celulose/química , Química Farmacêutica , Colo/diagnóstico por imagem , Composição de Medicamentos , Raios gama , Masculino , Metronidazol/administração & dosagem , Metronidazol/síntese química , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Pós , Coelhos , Cintilografia , Espectroscopia de Infravermelho com Transformada de Fourier , Pentetato de Tecnécio Tc 99m/química
16.
Folia Morphol (Warsz) ; 70(3): 143-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21866523

RESUMO

The olfactory organ of Oreochromis nilotica was studied by means of light and scanning electron microscopes. The oval shaped olfactory apparatus consists of 19-20 lamellae radiating from a central raphe. The receptor epithelium occupies the restricted area of the middle swollen region of the lamellae and is framed with receptor cells (both ciliated and microvillous) and rod cells. The larger part of the lateral surface of the olfactory lamella is covered with non-receptor epithelium, which is made up of stratified epithelial cells and mucous cells. The functional significance of various cells lining the olfactory epithelium of this fish are discussed.


Assuntos
Ciclídeos/anatomia & histologia , Mucosa Olfatória/ultraestrutura , Neurônios Receptores Olfatórios/ultraestrutura , Animais , Microscopia Eletrônica de Varredura
17.
SAR QSAR Environ Res ; 32(6): 473-493, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34011224

RESUMO

COVID-19 is the most unanticipated incidence of 2020 affecting the human population worldwide. Currently, it is utmost important to produce novel small molecule anti-SARS-CoV-2 drugs urgently that can save human lives globally. Based on the earlier SARS-CoV and MERS-CoV infection along with the general characters of coronaviral replication, a number of drug molecules have been proposed. However, one of the major limitations is the lack of experimental observations with different drug molecules. In this article, 70 diverse chemicals having experimental SARS-CoV-2 3CLproinhibitory activity were accounted for robust classification-based QSAR analysis statistically validated with 4 different methodologies to recognize the crucial structural features responsible for imparting the activity. Results obtained from all these methodologies supported and validated each other. Important observations obtained from these analyses were also justified with the ligand-bound crystal structure of SARS-CoV-2 3CLpro enzyme. Our results suggest that molecules should contain a 2-oxopyrrolidine scaffold as well as a methylene (hydroxy) sulphonic acid warhead in proper orientation to achieve higher inhibitory potency against SARS-CoV-2 3CLpro. Outcomes of our study may be able to design and discover highly effective SARS-CoV-2 3CLpro inhibitors as potential anticoronaviral therapy to crusade against COVID-19.


Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , Proteases 3C de Coronavírus/antagonistas & inibidores , Inibidores de Proteases/farmacologia , SARS-CoV-2/efeitos dos fármacos , Proteases 3C de Coronavírus/química , Desenho de Fármacos , Descoberta de Drogas , Modelos Moleculares , Inibidores de Proteases/química , Relação Quantitativa Estrutura-Atividade , SARS-CoV-2/enzimologia
18.
J Neurol Neurosurg Psychiatry ; 80(10): 1143-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19762901

RESUMO

Progressive supranuclear palsy (PSP) is an atypical parkinsonian syndrome characterised by akinesis, rigidity, falls, supranuclear gaze palsy and cognitive, particularly executive, dysfunction. This study examined the extent to which emotion recognition is affected by PSP. Although deficits in the recognition of emotion have been reported in several diseases which share clinicopathological characteristics with PSP, it has never been studied systematically in PSP. Twenty-four patients with probable or definite PSP and matched healthy controls were studied using tests of facial identity and facial emotion recognition. Patients were not impaired in recognising famous faces, but they showed significant deficits in the recognition of emotions, particularly negative emotions. Moreover, emotion recognition was strongly correlated with the severity of other cognitive deficits in PSP, but not disease duration. Deficits in emotion recognition form an integral part of the cognitive spectrum of the disease. The findings point to the pathological involvement of key regions necessary for the processing of emotions and to a subtype of PSP with cognitive and emotion recognition impairments. The acknowledgement of deficits in emotion recognition is important for management of both patients and their carers.


Assuntos
Emoções , Expressão Facial , Percepção , Reconhecimento Psicológico , Paralisia Supranuclear Progressiva/psicologia , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Paralisia Supranuclear Progressiva/patologia , Paralisia Supranuclear Progressiva/fisiopatologia
19.
Science ; 264(5162): 1152-6, 1994 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-8178175

RESUMO

Sib-pair analysis of 170 individuals from 11 Amish families revealed evidence for linkage of five markers in chromosome 5q31.1 with a gene controlling total serum immunoglobulin E (IgE) concentration. No linkage was found between these markers and specific IgE antibody concentrations. Analysis of total IgE within a subset of 128 IgE antibody-negative sib pairs confirmed evidence for linkage to 5q31.1, especially to the interleukin-4 gene (IL4). A combination of segregation and maximum likelihood analyses provided further evidence for this linkage. These analyses suggest that IL4 or a nearby gene in 5q31.1 regulates IgE production in a nonantigen-specific (noncognate) fashion.


Assuntos
Cromossomos Humanos Par 5 , Ligação Genética , Imunoglobulina E/sangue , Interleucina-4/genética , Adolescente , Adulto , Idoso , Alérgenos/imunologia , Sequência de Bases , Criança , Pré-Escolar , Feminino , Genes MHC da Classe II , Marcadores Genéticos , Humanos , Hipersensibilidade Imediata/genética , Funções Verossimilhança , Escore Lod , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular
20.
Brain ; 131(Pt 8): 2094-105, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18577547

RESUMO

Cognitive deficits are very common in Parkinson's disease particularly for 'executive functions' associated with frontal cortico-striatal networks. Previous work has identified deficits in tasks that require attentional control like task-switching, and reward-based tasks like gambling or reversal learning. However, there is a complex relationship between the specific cognitive problems faced by an individual patient, their stage of disease and dopaminergic treatment. We used a bimodality continuous performance task during fMRI to examine how patients with Parkinson's disease represent the prospect of reward and switch between competing task rules accordingly. The task-switch was not separately cued but was based on the implicit reward relevance of spatial and verbal dimensions of successive compound stimuli. Nineteen patients were studied in relative 'on' and 'off' states, induced by dopaminergic medication withdrawal (Hoehn and Yahr stages 1-4). Patients were able to successfully complete the task and establish a bias to one or other dimension in order to gain reward. However the lateral prefrontal cortex and caudate nucleus showed a non-linear U-shape relationship between motor disease severity and regional brain activation. Dopaminergic treatment led to a shift in this U-shape function, supporting the hypothesis of differential neurodegeneration in separate motor and cognitive cortico-striato-thalamo-cortical circuits. In addition, anterior cingulate activation associated with reward expectation declined with more severe disease, whereas activation following actual rewards increased with more severe disease. This may facilitate a change in goal-directed behaviours from deferred predicted rewards to immediate actual rewards, particularly when on dopaminergic treatment. We discuss the implications for investigation and optimal treatment of this common condition at different stages of disease.


Assuntos
Dopaminérgicos/uso terapêutico , Levodopa/uso terapêutico , Doença de Parkinson/psicologia , Idoso , Estudos de Casos e Controles , Núcleo Caudado/patologia , Cognição , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Movimento , Testes Neuropsicológicos , Doença de Parkinson/patologia , Córtex Pré-Frontal/patologia , Desempenho Psicomotor , Tempo de Reação , Recompensa
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