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1.
J Assoc Physicians India ; 68(12): 78-81, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33247651

RESUMO

Sea Snakes have the most potent venom among snakes known to mankind and a few species are implicated in human fatalities.1 Commonest Sea snake in the Indian Sea is Enhydrina Schistosa.2 Mortality is high in spite of therapy because of multiple complications. This is a Case report of two Fishermen who were bitten by Sea Snake and developed complications.


Assuntos
Mordeduras de Serpentes , Animais , Elapidae , Humanos , Mordeduras de Serpentes/complicações , Mordeduras de Serpentes/terapia , Peçonhas
2.
Asian Pac J Cancer Prev ; 19(11): 3203-3209, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30486611

RESUMO

Cervical cancer is the leading cancer in women around the world. In this paper, Adaptive Neuro Fuzzy Inference System (ANFIS) classifier based cervical cancer detection and segmentation methodology is proposed. This proposed system consists of the following stages as Image Registration, Feature extraction, Classifications and Segmentation. Fast Fourier Transform (FFT) is used for image registration. Then, Grey Level Co-occurrence Matrix (GLCM), Grey level and trinary features are extracted from the registered cervical image. Next, these extracted features are trained and classified using ANFIS classifier. Morphological operations are now applied over the classified cervical image to detect and segment the cancer region in cervical images. Simulations on large cervical image dataset demonstrate that the proposed cervical cancer detection and segmentation methodology outperforms the state of-the-art methods in terms of sensitivity, specificity and accuracy.


Assuntos
Algoritmos , Detecção Precoce de Câncer/métodos , Lógica Fuzzy , Processamento de Imagem Assistida por Computador/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Neoplasias do Colo do Útero/diagnóstico , Feminino , Humanos , Prognóstico , Processamento de Sinais Assistido por Computador , Neoplasias do Colo do Útero/diagnóstico por imagem
3.
J Pharm Bioallied Sci ; 9(Suppl 1): S73-S78, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29284939

RESUMO

AIM: This study aims to compare the smear layer removal efficacy of 2% chitosan (low molecular weight) (C-LMV), 4% chitosan citrate (CC), and 10% citric acid (CA) when used in specific irrigant protocols. MATERIALS AND METHODS: A total of 60 single-rooted maxillary incisors and canines were decoronated, standardized to a root length of 15 mm, and prepared with rotary files up to protaper F3 size. Sodium hypochlorite was used as initial rinse [8 ml]. The samples were divided into experimental (Group III, IV, V, and VI) (n = 10) and control groups (I - 17% EDTA, II - normal saline) (n = 5) based on the type of final rinse solution (5 ml) used, that is, 2% C-LMV, 4% C-citrate, 10% CA, and 1% acetic acid. Samples were dehydrated, split buccolingually, gold sputter coated, and examined in field emission scanning electron microscope. RESULTS: Overall, the Group IV, V, and III presented the least amounts of smear, debris, and erosion among the experimental groups at the apical, middle, and coronal one-thirds of the root canal with a mean value of 1.53 ± 0.42, 1.33 ± 0.42, and 1.60 ± 0.46, respectively, and there was no statistically significant difference (P > 0.05). CONCLUSION: The use of CC as final rinse solution during biomechanical preparation seems promising.

4.
Artigo em Inglês | MEDLINE | ID: mdl-27208759

RESUMO

Herein, we report a simple, one step synthesis of hybrid copper oxide nanoneedles on graphene oxide sheets (GO-CuONNs) through sonochemical method. The present method affords a facile mean for controlling effective concentration of the active CuO nanoneedles on the graphene oxide sheets, and also offers the necessary stability to the resulting GO-CuONNs structure for adsorption transformations.Furthermore, this hybrid GO-CuONNs is successfully employed in the removal of a series of hazardous ionic organic dyes namely coomassie brilliant blue, methylene blue, congo red and amidoblack 10B. Through careful investigation of the material, we found that the synergetic effect between CuONNs and GO play a significant role in the adsorption of all the dyes studied. The prepared hybrid material contains both hydrophobic and hydrophilic environment which is expected to enhance the electrostatic interaction between the adsorbent and the dye molecules, consequently favouring the adsorption process.

5.
J Pharm Bioallied Sci ; 7(Suppl 2): S712-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26538950

RESUMO

Invasive cervical resorption is often not diagnosed properly, leading to improper treatment or unnecessary loss of the tooth structure. Early diagnosis and appropriate treatment are the keys to a successful outcome of therapy. Invasive cervical resorption is often seen in the cervical area of the tooth, but because it is initiated apical to the epithelial attachment, it can present anywhere in the root. In the early stages, it may be symmetrical, but larger lesions have the tendency to be asymmetrical. It can expand apically or coronally.

6.
Indian J Exp Biol ; 53(12): 779-85, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26742322

RESUMO

Leptospirosis is a bacterial disease caused by bacteria of the genus Leptospira affecting humans and animals. Untreated leptospirosis may result in severe kidney damage, meningitis, liver failure, respiratory distress, and even death. Virulent leptospirosis can rapidly enter kidney fibroblasts and induce a programmed cell death. Thus, it is a challenge for immunologists to develop an effective and safe leptospirosis vaccine. Here, we compared the commercial canine leptospira vaccine and recombinant proteins (OmpL1 and LipL41) with and without adjuvant in terms of immune response and challenge studies in hamsters and immune response studies alone in experimental dogs. The outer membrane proteins viz., lipL41 and OmpL1 of leptospira interrogans serovars icterohaemorrhagiae were amplified. The primers were designed in such a way that amplified products of OmpL1 and lipL41 were ligated and cloned simultaneously into a single vector. The cloned products were expressed in E. coli BL21 cells. The immunoprotection studies were conducted for both recombinant proteins and commercial vaccine. The challenge experiment studies revealed that combination of both rLip41 and rOmpL1 and commercial vaccine gave 83% and 87% protection, respectively. Histopathological investigation revealed mild sub lethal changes were noticed in liver and kidney in commercially vaccinated group alone. The immune responses against recombinant leptospiral proteins were also demonstrated in dogs.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas Bacterianas/imunologia , Leptospira/imunologia , Leptospirose/prevenção & controle , Vacinas Sintéticas/imunologia , Adjuvantes Imunológicos/farmacologia , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Vacinas Bacterianas/genética , Cricetinae , Modelos Animais de Doenças , Cães , Imunização , Leptospira/genética , Leptospirose/imunologia , Leptospirose/microbiologia , Vacinas Sintéticas/genética
7.
J Nat Sci Biol Med ; 5(1): 82-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24678203

RESUMO

AIM: The aim of the study was to evaluate the osseo-integration and soft tissue status of the endosseous implants placed in immediate extraction socket. METHODOLOGY: Seven patients (4 males and 3 females) aged 20-30 years were selected for the study. Nine implants were placed in seven patients in the maxillary arch. All the patients were clinically αnd thoroughly examined. Under local anesthesia, the indicated tooth was extracted. The extracted socket was prepared using standard drills with palatal wall as guide. The longest and widest implants were placed (Hi-Tec Implants). All implants showed good primary stability. The implants used in the study were tapered design endosseous implants with Threaded implants (TI) unit plasma-sprayed surface. Surgical re-entry (secondary surgery) was performed to remove the healing cap after 6 months for supra crestal fabrication. All patients were reviewed periodically at 3(rd) and 6(th) month interval and the following clinical parameters including modified plaque index (mPlI), modified bleeding index (mBI), probing depth (PD), attachment level (AL), and distance between the implant shoulder and mucosal margin (DIM), distance between the implant shoulder and first bone-implant contact, and Clinical Mobility Index were recorded. The results were computed and subjected to statistical evaluation. RESULTS: The mPlI, mBI, PD, AL, and DIM were evaluated around the implants at baseline, 3(rd) and 6(th) month intervals and analyzed statistically by Friedman T-test. The results of the above were shown to be statistically non-significant. The distance between the implant shoulder and first bone implant contact was evaluated around the implants at base line, 3(rd) and 6(th) month intervals. The results proved to be statistically significant (0.01) implying that there was a bone apposition around the implants. CONCLUSION: During the course of the study, soft tissue status around implants was found to be healthy. Osseointegration as assessed by clinical and radiographic findings was found to be sound.

8.
ACS Nano ; 8(1): 671-9, 2014 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-24350837

RESUMO

Ionic liquids are room-temperature molten salts that are increasingly used in electrochemical devices, such as batteries, fuel cells, and sensors, where their intrinsic ionic conductivity is exploited. Here we demonstrate that combining anionic, redox-active Au25 clusters with imidazolium cations leads to a stable ionic liquid possessing both ionic and electronic conductivity. The Au25 ionic liquid was found to act as a versatile matrix for amperometric enzyme biosensors toward the detection of glucose. Enzyme electrodes prepared by incorporating glucose oxidase in the Au25 ionic liquid show high electrocatalytic activity and substrate affinity. Au25 clusters in the electrode were found to act as effective redox mediators as well as electronic conductors determining the detection sensitivity. With the unique electrochemical properties and almost unlimited structural tunability, the ionic liquids of quantum-sized gold clusters may serve as versatile matrices for a variety of electrochemical biosensors.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas/instrumentação , Ouro/química , Líquidos Iônicos , Nanoestruturas , Enzimas Imobilizadas/química , Glucose/análise , Glucose Oxidase/química
9.
Environ Monit Assess ; 185(6): 5327-38, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23135061

RESUMO

The reefs in some islands of Andaman and Nicobar suffered severe damage following a tropical storm in the Bay of Bengal off Myanmar coast during 13-17 March 2011. Surveys were conducted at eight sites in Andaman, of which five were located in the Ritchie's Archipelago where maximum wind speeds of 11 m s(-1) was observed; and three around Port Blair which lay on the leeward side of the storm and had not experienced wind speeds of more than 9 m s(-1). Corals in the shallow inshore reefs were broken and dislodged by the thrust of the waves. Significant damage in the deeper regions and offshore reefs were caused by the settlement of debris and sand brought down from the shallower regions. The fragile branching corals (Acropora sp.) were reduced to rubbles and the larger boulder corals (Porites sp.) were toppled over or scarred by falling debris. The reefs on the windward side and directly in the path of the storm winds were the worst affected. The investigation exposes the vulnerability of the reefs in Andaman to the oceanographic features which generally remain unnoticed unless the damage is caused to the coastal habitats.


Assuntos
Recifes de Corais , Tempestades Ciclônicas , Monitoramento Ambiental , Animais , Antozoários , Conservação dos Recursos Naturais , Mianmar , Movimentos da Água
10.
J Pharm Bioallied Sci ; 4(Suppl 2): S125-30, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23066232

RESUMO

AIM: The action of irrigant solutions on intra- radicular dentinal surface were evaluated in an in vitro setting using a scanning electron microscope (SEM) and it was observed that sodium hypochlorite and MTAD produced the cleanest surface and that none of the irrigants were able to produce an ideal preparation of the dentinal surface when used individually. The primary objective of endodontic therapy is to achieve a clean, optimal environment in root canals to avoid unsuccessful treatment outcomes. The complexities of the root canal system necessitate the use of irrigating solutions which act on radicular dentin surface, modifying it. The action of irrigants can be beneficial, and yet at the same time, as they modify the surface structure of dentin, they can have an adverse impact on the properties of dentin. The present study was undertaken to assess the effect of various irrigants on the dentinal surface using an SEM. MATERIALS AND METHODS: Forty-five roots were randomly divided into nine groups (n=5) and prepared by sectioning at the level of cemento-enamel junction (CEJ) and 10 mm from the CEJ and split longitudinally. The dentin surface was prepared and the cemental surfaces were coated with double layer of varnish. The irrigants tested were normal saline, de-ionized water, 17% ethylenediaminetetraacetic acid (EDTA), 5% sodium hypochlorite (NaOCl), 5% NaOCl with ultrasonic agitation, 3% hydrogen peroxide, 2% chlorhexidine (CHX), MTAD, and MTAD with ultrasonic agitation. The prepared samples were placed in the irrigant solution for 3 min, subsequently dehydrated, sputter coated, and observed under SEM. The images were subsequently analyzed for dentinal surface changes. RESULTS: 17% EDTA and MTAD produced the cleanest dentinal surface. Ultrasonic agitation enhanced the effect of irrigants. 5% NaOCl and 3% hydrogen peroxide were efficient at removal of organic debris, but were unable to remove the smear layer. De-ionized water, normal saline, and 2% chlorhexidine were not effective at removing the debris or the smear layer. CONCLUSION: None of the irrigants individually were able to achieve conditions of an ideal dentinal surface preparation.

11.
J Pharm Bioallied Sci ; 4(Suppl 2): S197-202, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23066252

RESUMO

CONTEXT: Influence of luting agent, design of tooth preparation for cast posts on tooth resistance to fracture. AIM: To evaluate fracture resistance of teeth restored with cast posts and cores with or without cervical ferrule and cemented with zinc phosphate, glass ionomer, or resin cement. MATERIALS AND METHODS: Sixty single-rooted maxillary first premolars of similar sizes were selected. Biomechanical preparation and post space preparation for cast post was done for all samples and then they were divided into two groups (n=30). Cervical ferrule preparation was done for Group A, and Group B was prepared without any cervical ferrule. Both groups were further divided into three subgroups (1, 2, and 3; n=10) Cast posts for subgroups 1, 2, and 3 were cemented with zinc phosphate, glass ionomer, and resin cement, respectively. A shearing load was applied to indented buccal cusp of specimens at an angle of 45° in universal testing machine at a cross-head speed of 1 mm/min until fracture. RESULTS: Specimens with ferrule (Group A) had significantly higher shear bond strength values (mean 1503.37 N) than specimens without ferrule (Group B) (mean 1052.09 N). CONCLUSION: Inclusion of ferrule in tooth preparations for posts increased the fracture resistance regardless of the luting agent.

12.
Nanoscale ; 4(14): 4240-6, 2012 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-22592148

RESUMO

We report here the selective determination of dopamine (DA) using quantum-sized gold nanoparticles coated with charge selective ligands. Glutathione protected gold nanoparticles (GS-Au(25)) were synthesized and immobilized into a sol-gel matrix via thiol linkers. The GS-Au(25) modified sol-gel electrode was found to show excellent electrocatalytic activity towards the oxidation of DA but no activity towards the oxidation of ascorbic acid. The role of electrostatic charge in the selective electrocatalytic activity of GS-Au(25) was verified by voltammetry of redox markers carrying opposite charges. The pH dependent sensitivity for the determination of DA further confirmed the charge screening effect of GS-Au(25). Mechanistic investigation revealed that the selectivity is attained by the selective formation of an electrostatic complex between the negatively charged GS-Au(25) and DA cation. The GS-Au(25) modified sol-gel electrode also showed excellent selectivity for DA in the presence of an interferent, ascorbic acid.


Assuntos
Dopamina/análise , Técnicas Eletroquímicas , Ouro/química , Nanopartículas Metálicas/química , Ácido Ascórbico , Catálise , Eletrodos , Géis/química , Concentração de Íons de Hidrogênio , Ligantes , Oxirredução , Compostos de Sulfidrila
13.
Indian J Dent Res ; 22(1): 34-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21525674

RESUMO

BACKGROUND: Oil pulling has been used extensively as a traditional Indian folk remedy without scientific proof for many years for strengthening teeth, gums and jaws and to prevent decay, oral malodor, bleeding gums and dryness of throat and cracked lips. AIM: The aim of this study was to evaluate the antibacterial activity of sesame oil and lignans isolated from sesame oil on oral microorganisms and to check whether saponification or emulsification occurs during oil-pulling therapy. MATERIALS AND METHODS: The in vitro study was carried out in three different phases: (1) Antibacterial activity of the lignans and sesame oil were tested by minimum inhibitory concentration assay by agar dilution method and agar well diffusion method, respectively. (2) Increase in free fatty acid level of oil and the quantity of sodium hydroxide (NaOH) used up in the titration are good indicators of saponification process. This was assessed using analytical tests for vegetable oils. (3) Swished oil was observed under light microscope to assess the status of the oil, presence of microorganisms, oral debris and foreign bodies. RESULTS: Sesamin and sesamolin isolated from sesame oil did not have any antibacterial effect against oral microorganisms like Streptococcus mutans, Streptococcus mitis and Streptococcus viridans. Emulsification of sesame oil occurs during oil-pulling therapy. Increased consumption of NaOH in titration is a definite indication of a possible saponification process. CONCLUSION: The myth that the effect of oil-pulling therapy on oral health was just a placebo effect has been broken and there are clear indications of possible saponification and emulsification process, which enhances its mechanical cleaning action.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Antissépticos Bucais/uso terapêutico , Higiene Bucal/métodos , Óleo de Gergelim/uso terapêutico , Anti-Infecciosos Locais/química , Terapias Complementares , Humanos , Antissépticos Bucais/química , Óleo de Gergelim/química
14.
Anal Chem ; 83(9): 3244-7, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21456614

RESUMO

This paper describes the electrocatalytic activity of quantum-sized thiolate protected Au(25) nanoparticles and their use in electrochemical sensing. The Au(25) film modified electrode exhibited excellent mediated electrocatalytic activity that was utilized for amperometric sensing of biologically relevant analytes, namely, ascorbic acid and uric acid. The electron transfer dynamics in the Au(25) film was examined as a function of Au(25) concentration, which manifested the dual role of Au(25) as an electronic conductor as well as a redox mediator. The electron transfer study has further revealed the correlation between the electronic conductivity of the Au(25) film and the sensing sensitivity.

15.
Braz. j. pharm. sci ; 46(4): 785-793, Oct.-Dec. 2010. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-622879

RESUMO

The objective of this study was to develop a sustained release dosage form of Trimetazidine dihydrochloride (TMZ) using a natural polymeric carrier prepared in a completely aqueous environment. TMZ was entrapped in calcium alginate beads prepared with sodium alginate by the ionotropic gelation method using calcium chloride as a crosslinking agent. The drug was incorporated either into preformed calcium alginate gel beads (sequential method) or incorporated simultaneously during the gelation stage (simultaneous method). The beads were evaluated for particle size and surface morphology using optical microscopy and SEM, respectively. Beads produced by the sequential method had higher drug entrapment. Drug entrapment in the sequential method was higher with increased CaCl2 and polymer concentration but lower with increased drug concentration. In the simultaneous method, drug entrapment was higher when polymer and drug concentration were increased and also rose to a certain extent with increase in CaCl2 concentration, where further increase resulted in lower drug loading. FTIR studies revealed that there is no interaction between drug and CaCl2. XRD studies showed that the crystalline drug changed to an amorphous state after formulation. Release characteristics of the TMZ loaded calcium alginate beads were studied in enzyme-free simulated gastric and intestinal fluid.


O objetivo deste estudo foi desenvolver forma de liberação controlada de dicloridrato de trimetazidina (TMZ) utilizando transportador plomérico natural em ambiente completamente aquoso. A TMZ foi presa em pérolas de alginato de cálcio preparadas com alginato de sódio pelo método de gelatinização ionotrópica, usando cloreto de cálcio como agente de formação de ligações cruzadas. O fármaco foi incorporado nas pérolas de gel de alginato de cálcio (método sequencial) ou incorporado, simultaneamente, durante o estágio de gelificação (método simultâneo). As pérolas foram avaliadas quanto ao tamanho das partículas e morfologia da superfície utilizando microscopia óptica de SEM, respectivamente. As pérolas produzidas pelo método sequencial apresentaram maior capacidade de inclusão. No método sequencial, a inclusão de fármaco foi maior com o aumento de CaCl2 e da concentração do plímero, mas menor com o aumento da concentração de fármaco. No método simultâneo, a inclusão de fármaco foi mais alta quando as concentrações de fármaco e plímero foram aumentadas e, também, atingiram certa extensão com aumento na concentração de CaCl2, cujo aumento posterior resultou em carga menor de fármaco. Estudos de FTIR revelaram que não há interação entre fármaco e CaCl2. Estudos de XRD mostraram que o fármaco mudou do estado cristalino para o amorfo após a formulação. As características de liberação de TMZ das pérolas carregadas com alginato de cálcio foram estudadas em fluidos simulados, gástrico e intestinal, livres de enzima.


Assuntos
Cálcio/farmacologia , Cápsulas/análise , Cápsulas/farmacocinética , Cápsulas/química , Técnicas In Vitro , Desenho de Fármacos , Geleificantes , Química Farmacêutica/métodos , Sódio , Trimetazidina/farmacologia
16.
Bioorg Med Chem Lett ; 18(24): 6357-61, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-18993064

RESUMO

In this letter, we report discovery of diacylphloroglucinol compounds as a new class of GPR40 (FFAR1) agonists. Several diacylphloroglucinols with varying length of acyl functionality and substitution on aromatic hydroxyls were synthesized and evaluated for GPR40 agonism using functional calcium-flux assay. Out of 17 compounds evaluated, 14, 17, 19 and 25 exhibited good GPR40 agonistic activity with EC(50) values ranging from 0.07 to 8 microM (pEC(50) 7.12-5.09), respectively, with maximal agonistic response of 84-102%.


Assuntos
Química Farmacêutica/métodos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Floroglucinol/análogos & derivados , Floroglucinol/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Animais , Células CHO , Cálcio/química , Cricetinae , Cricetulus , Desenho de Fármacos , Ácidos Graxos/química , Humanos , Ligantes , Modelos Químicos , Floroglucinol/síntese química , Ratos
18.
Talanta ; 76(1): 54-9, 2008 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-18585240

RESUMO

Nickel aquapentacyanoferrate (NAPCF), a novel transition metal complex has been prepared and its ability to act as an electrocatalyst for BHA oxidation has been demonstrated. The cyclic voltammetric behaviour of the NAPCF modified electrode prepared by mechanical immobilization on the graphite electrode was well defined. A pair of redox peaks corresponding to the electrochemical behaviour of the NAPCF was observed at 0.35 V and 0.31 V, corresponding to the anodic and cathodic peaks respectively, with a formal potential of 0.33 V. The NAPCF modified electrode favoured electrocatalytic oxidation of BHA to occur at a greatly minimized overpotential of 0.48 V. Experiments were performed to characterize the electrode as an amperometric sensor for the determination of BHA. The anodic peak current was linearly related to BHA concentration in the range of 6.24x10(-7) M to 2.19x10(-4) M with a detection limit of 2.49x10(-7) M and a correlation coefficient of 0.9979. Amperometry in stirred solution exhibited quick and sensitive response to BHA, showing the possible application of the modified electrode in flow system analysis. The modified electrode retained its initial response for more than 2 months when stored in supporting electrolyte, owing to the chemical and mechanical stability of the NAPCF mediator. This modified electrode was also quite effective in the determination of BHA in commercial samples.


Assuntos
Hidroxianisol Butilado/análise , Ferrocianetos/química , Catálise , Eletroquímica , Eletrodos , Análise de Alimentos , Mecânica , Oxirredução , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise Espectral
19.
J Environ Biol ; 27(3): 561-6, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17402250

RESUMO

The present study was carried out to determine the water quality in terms of physicochemical characteristics and plankton distribution in the coastal waters of Kattumavadi, Palk Bay for a period of one year from April 2002 to March 2003. Air and surface water temperatures varied from 28 degrees C to 32.50 degrees C and from 27.5 to 32.0 degrees C while light extinction coefficient (LEC) varied between 0.95 and 1.85. Salinity ranged from 26.0 to 34.5 per thousand and the pH ranged between 7.95 and 8.35. Variation in dissolved oxygen content was from 4.15 to 7.18 ml(-1), and the particulate organic carbon (POC) content varied between 0.49 and 2.28 mgCl(-1). Concentrations of nutrients viz. nitrate (2.15 to 8.28 microM), nitrite (0.12 to 0.62 microM), inorganic phosphate (1.28 to 2.15 microM) and reactive silicate (5.15 to 12.52 microM) also varied independently. Chlorophyll a content ranged from 0.28 to 1.48 mg m(-3) and the primary productivity, from 4.19 to 16.08 mgCm(-3) hr(-1). The present study recorded a total of 43 species of planktonic diatoms and two species of blue-green algae. Population density of phytoplankton varied from 18,000 to 34,000 cells l(-1). Percentage composition, of the diatoms showed minimum values during the monsoon season and the maximum values during the premonsoon season.


Assuntos
Fitoplâncton/classificação , Água/química , Índia , Especificidade da Espécie
20.
J Virol ; 80(1): 412-25, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16352566

RESUMO

Rotavirus NSP4 is a multifunctional endoplasmic reticulum (ER)-resident nonstructural protein with the N terminus anchored in the ER and about 131 amino acids (aa) of the C-terminal tail (CT) oriented in the cytoplasm. Previous studies showed a peptide spanning aa 114 to 135 to induce diarrhea in newborn mouse pups with the 50% diarrheal dose approximately 100-fold higher than that for the full-length protein, suggesting a role for other regions in the protein in potentiating its diarrhea-inducing ability. In this report, employing a large number of methods and deletion and amino acid substitution mutants, we provide evidence for the cooperation between the extreme C terminus and a putative amphipathic alpha-helix located between aa 73 and 85 (AAH73-85) at the N terminus of DeltaN72, a mutant that lacked the N-terminal 72 aa of nonstructural protein 4 (NSP4) from Hg18 and SA11. Cooperation between the two termini appears to generate a unique conformational state, specifically recognized by thioflavin T, that promoted efficient multimerization of the oligomer into high-molecular-mass soluble complexes and dramatically enhanced resistance against trypsin digestion, enterotoxin activity of the diarrhea-inducing region (DIR), and double-layered particle-binding activity of the protein. Mutations in either the C terminus, AAH73-85, or the DIR resulted in severely compromised biological functions, suggesting that the properties of NSP4 are subject to modulation by a single and/or overlapping highly sensitive conformational domain that appears to encompass the entire CT. Our results provide for the first time, in the absence of a three-dimensional structure, a unique conformation-dependent mechanism for understanding the NSP4-mediated pleiotropic properties including virus virulence and morphogenesis.


Assuntos
Enterotoxinas/química , Glicoproteínas/química , Rotavirus/química , Toxinas Biológicas/química , Proteínas não Estruturais Virais/metabolismo , Linhagem Celular , Enterotoxinas/fisiologia , Glicoproteínas/genética , Glicoproteínas/metabolismo , Toxinas Biológicas/genética , Toxinas Biológicas/metabolismo , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética
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