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1.
Rev Sci Instrum ; 93(2): 023504, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35232154

RESUMO

India is responsible for the supply of diagnostic neutral beam systems for ITER to diagnose its helium ash during the deuterium-tritium plasma phase using the charge exchange recombination spectroscopy technique. Considering the many first of its kind in terms of technologies and beam development aspects, ITER Indian domestic agency has adopted a strategy of developing the technology and beam experimentation in parallel. On the beam development front three test beds, namely, the ROBIN (Rf Operated Beam source in India for Negative ion research), the TWIN (TWo rf driver-based Indigenously built Negative ion source), and the INTF (INdian Test Facility) are presently in their various phases of operation, optimization, and setting up at IPR, respectively. Experiments related to plasma production, beam production, and acceleration up to 30 keV in volume and surface mode have been performed on ROBIN. The maximum negative hydrogen ion current density to a tune of 27 mA/cm2 is obtained in the surface mode with Cs injection. Optimal source performance requires optimal surface conditions, minimum impurities, careful characterization of the plasma, cesium feed and its redistribution, and optimal wall temperatures of the surfaces of the plasma box and the plasma grid. A combination of probe, optical, vacuum, laser based, electrical, and calorimetric diagnostic measurements enables such a control. At ROBIN, the above diagnostics are being used regularly. The operational and diagnostic experiences on ROBIN shall provide the desired experience and database for operations of TWIN and INTF in the coming years. A large number of conventional and advanced diagnostic techniques are used for plasma and beam characterization. These diagnostics are suitable not only to detect and understand the plasma but also for studies related to impurity evolution. The temporal evolution of impurities significantly impacts the plasma and beam properties. The studies help in establishing correlations between physical parameters and operational parameters to optimize the source performance ensuring adequate safety and investment protection. This paper will present a brief overview of various diagnostics implemented, lessons learned, and the results obtained from ROBIN. In addition, an outline of the diagnostics planned for INTF based on the experience and understandings developed during the present experiments on ROBIN and TWIN and considering the requirements of large systems shall be discussed.

2.
Infect Genet Evol ; 71: 7-15, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30807843

RESUMO

Documentation of the emergence of Porcine circovirus 2 (PCV2) infection and economic losses incurred due to high mortality has been reported worldwide. The prevalence and genetic diversity of the virus has been reported in Northeast India including the possible chances of Classical swine fever virus (CSFV) vaccine failure in pig population in this region resulting in major disease outbreak. Irrespective of the genetic variability, the emergence of a novel cluster (based on the ORF2 phylogeny) was reported last year. The present study describes a state-wide (Meghalaya, India) molecular epidemiological investigation of PCV2 strains in pig population by amplification, sequencing and undertaking phylogenetic analyses. The results indicate the identification of a novel cluster of PCV2 originating from the inter-genotypic recombination between PCV2c and PCV2d. Multiple sequence alignment of amino acids indicates possible substitution in the A, B and C domains of the capsid protein. Molecular structural modelling of the capsid protein of PCV2 indicated possible motif variations in the secondary structure including presence of a tunnel, encountered at the interface region on each chain facilitating in transportation of molecules and acting as an active site for attachment and penetration. The baseline data strengthens the existing control programme of PCV2 and is possibly helpful in the planning of active surveillance strategy in this region.


Assuntos
Proteínas do Capsídeo/genética , Infecções por Circoviridae/veterinária , Circovirus/genética , Doenças dos Suínos/virologia , Animais , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/virologia , Variação Genética , Índia/epidemiologia , Modelos Moleculares , Epidemiologia Molecular , Filogenia , Recombinação Genética , Suínos , Doenças dos Suínos/epidemiologia
3.
Virusdisease ; 29(1): 89-95, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29607364

RESUMO

The present study focused on the detection and genetic characterisation of 5' untranslated region (5'UTR) and E2 gene of classical swine fever virus (CSFV, family Flaviviridae, genus Pestivirus) from bovine population of the northeastern region of India. A total of 134 cattle serum samples were collected from organised cattle farms and were screened for CSFV antigen with a commercial antigen capture enzyme linked immunosorbent assay (Ag-ELISA) and reverse transcription-polymerase chain reaction (RT-PCR). A total of 10 samples were positive for CSFV antigen by ELISA, while all of them were positive in PCR for 5'UTR region. Full length E2 region of CSFV were successfully amplified from two positive samples and used for subsequent phylogenetic analysis and determination of protein 3D structure which showed similarity with reported CSFV isolate from Assam of sub-genogroup 2.1, with minor variations in protein structure.

4.
Mymensingh Med J ; 23(2): 401-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24858176

RESUMO

Uterine prolapse is commonly seen in the geriatric age group. Congenital vaginouterine prolapse is a rare condition occurring in neonates and is usually associated with spinal cord malformations in about 85% of cases. Several modalities of treatment have been described for neonatal uterine prolapse. Conservative treatment in the form of simple digital reposition, use of pessary or other self-retaining device is usually sufficient to treat this condition, which is self-limiting and regressive. Here we report our first case of neonatal uterine prolapse, managed successfully with simple digital reposition.


Assuntos
Prolapso Uterino/congênito , Prolapso Uterino/terapia , Feminino , Humanos , Recém-Nascido , Prolapso Uterino/diagnóstico
5.
J Phys Condens Matter ; 21(9): 095005, 2009 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21817378

RESUMO

Resonant inelastic x-ray scattering (RIXS), x-ray absorption spectroscopy and x-ray excited optical luminescence (XEOL) have been used to measure element specific filled and empty electronic states over the Si L(2,3) edge of passivated Si nanocrystals of narrow size distribution (diameter 2.2 ± 0.4 nm). These techniques have been employed to directly measure absorption and luminescence specific to the local Si nanocrystal core. Profound changes occur in the absorption spectrum of the nanocrystals compared with bulk Si, and new features are observed in the nanocrystal RIXS. Clear signatures of core and valence band exciton formation, promoted by the spatial confinement of electrons and holes within the nanocrystals, are observed, together with band narrowing due to quantum confinement. XEOL at 12 K shows an extremely sharp feature at the threshold of orange luminescence (i.e., at ∼1.56 eV (792 nm)) which we attribute to recombination of valence excitons, providing a lower limit to the nanocrystal band gap.

6.
Indian J Pharmacol ; 41(3): 106-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20442816

RESUMO

OBJECTIVE: To study the variation of disposition kinetic values of sparfloxacin in healthy, hepatopathic, and nephropathic chickens after a single intravenous administration. MATERIALS AND METHODS: Hepatotoxicity was induced by the administration of paracetamol (500 mg / kg / day, p.o. for seven days) and nephrotoxicity by uranyl nitrate (2.0 mg / kg / day dissolved in distilled water, i.v. for four days) in chickens. Disposition kinetic studies of sparfloxacin were investigated in healthy as well as hepatopathic and nephropathic birds after a single intravenous administration at 40 mg / kg body weight. RESULTS: Maximum plasma concentration detected at 0.16 hour was 31.25 +/- 2.95, 61.95 +/-1.85, and 99.86 +/- 2.21 mug / ml in healthy, hepatopathic, and nephropathic group, respectively. The drug could not be detected in the plasma of healthy birds beyond 12-hour period, while the same was detectable for 72 hour in the plasma of hepatopathic and nephropathic birds. The concentration of sparfloxacin was significantly (P < 0.01) higher in all the samples of hepathopathic and nephropathic birds compared to healthy birds. All the kinetic values were increased (P < 0.01) in the hepatopathic and nephropathic birds, except Vd(area) and Cl(B) values in hepatopathic Birds; while beta and Cl(B) values nephropathic birds were decreased significantly than that of healthy birds. CONCLUSIONS: The dose of sparfloxacin may be reduced in hepatopathic as well as nephropathic birds.

7.
Micron ; 38(2): 158-64, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16950626

RESUMO

A phase/amplitude mask on the aperture of an imaging system results in a pupil function that is multiplicative with the lens function, resulting in a morphological transformation of the imaging wavefront. It was shown that such amplitude and phase functions can be implemented using polarization masks, with the advantage that the phase and amplitude can be controlled in real time and in some cases, independently of each other. The phase and amplitude variation over the mask can be controlled either by changing the polarization of the mask or by changing the input beam parameters. Wavefront tailoring using polarization-masked apertures is therefore feasible and may be utilized for focal shift and partial aberration compensation. For complete compensation of aberration, the phase distribution over the mask should be conjugate to that of the phase error of the aberrant wavefront, which necessitates the use of a continuously variable polarization mask. Since such a mask is difficult to implement, we have considered polarizing masks consisting of discrete polarized zones on the lens aperture, leading to polarization phase steps on the exit pupil of the imaging system. The simulation results presented in this paper show that effects of focal shift, partial compensation of primary spherical aberration and astigmatism can indeed be achieved by the proper use of polarization masked apertures.

8.
Indian J Public Health ; 49(4): 227-30, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16479903

RESUMO

A series of Community Psychiatric Clinics were conducted in different blocks of Sundarban region of West Bengal. One of the primary objectives of this was to collect clinical epidemiological data on psychiatric morbidity in the region. A total of 26 clinics were conducted in Sagar, Kakdwip, Canning and Gosaba block of the Sundarban region during the period from end 1998 to end 2000. A total of 451 psychiatric cases with diagnostic categories (male 239, female 212) and 215 non-psychiatric cases (male 107 and female 108) were seen in these clinics. Diagnostic Interview Schedules (SCID) and Clinical rating scales like Hamilton Depression Rating Scale and Brief Psychiatric Rating Scales were used to ascertain clinical diagnosis quantitatively. Special emphasis was given on common psychiatric disorders.


Assuntos
Serviços Comunitários de Saúde Mental/estatística & dados numéricos , Transtornos Mentais/epidemiologia , Feminino , Inquéritos Epidemiológicos , Humanos , Índia/epidemiologia , Masculino , Avaliação das Necessidades
9.
Indian J Med Res ; 120(4): 248-76, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15520481

RESUMO

India is classified along with the sub-Saharan African countries to be among those with a high burden and the least prospects of a favourable time trend of the disease as of now (Group IV countries). The average prevalence of all forms of tuberculosis in India is estimated to be 5.05 per thousand, prevalence of smear-positive cases 2.27 per thousand and average annual incidence of smear-positive cases at 84 per 1,00,000 annually. The credibility and use of the estimates are discussed in detail. Reports on recent studies on the time trend of the disease from some areas in India, e.g., Chingleput in Tamil Nadu are discussed. They confirm the slow downward trend over a fairly long period of observation, as in the rural areas around Bangalore. It also outlines the serious escalation of disease burden in a tribal population group in Car Nicobar over a period 1986-2002, and highlights the nature and extent of the emerging threats. Some epidemiologists forecast a rise of 20 per cent in incidence in the next 20 yr, for India, with a cumulative rise of 46 million cases of tuberculosis during that period, largely as a consequence of HIV epidemic. The Governmental efforts at intervention through Revised National Tuberculosis Control Programme (RNTCP) and at monitoring the epidemiology of intervention through organising routine reporting are highlighted, and data are presented and evaluated on these. RNTCP needs to be used as an effective instrument to bring a change in epidemiological situation, through fast expansion and achievement of global target. The present review describes the global tuberculosis situation, and views it in the context of the goal of the antituberculosis intervention activities. It presents the epidemiological situation in India, comments on the current trend and discusses the efforts taken towards making projections on the likely burden of disease in India over time.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Tuberculose/epidemiologia , Tuberculose/prevenção & controle , Demografia , Previsões , Infecções por HIV/epidemiologia , Humanos , Índia/epidemiologia , Modelos Teóricos , Prevalência
11.
Int J Environ Health Res ; 14(2): 143-9, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15203459

RESUMO

Human response to blast induced ground vibration and air-overpressure/noise is a major concern of current mining activity. This is because the fact that mines are fast transgressing the habitats and people are getting educated. Consequently the response of humans is changing and expectedly will increase in days to come with no viable and economic alternative to blasting--an essential component of mining. The response of humans can be purely physiological or psychological in nature or combination of both depending upon the situation and conditions of mining. Where physiological response is documented in terms of effects on ears and lungs there is a meager amount or no literature available regarding effects of blasting on the brain. Moreover, the studies on transitory phenomenon like the effects of blasting on humans are rare in comparison to the whole body vibration studies. This study was designed to address the issues as a precursor to a major initiative. The preliminary investigations conducted with the monitoring of EEG responses of humans to vibration and air-overpressure/noise due to blasting revealed that there is no major response of the brain to transitory vibrations and noise.


Assuntos
Explosões , Mineração , Ruído Ocupacional/efeitos adversos , Exposição Ocupacional , Vibração/efeitos adversos , Adulto , Idoso , Córtex Cerebral/fisiologia , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pressão
12.
Bull World Health Organ ; 82(11): 836-43, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15640919

RESUMO

OBJECTIVE: To assess the tuberculosis (TB) situation in the tribal community of Car Nicobar island 15 years after the national TB programme was implemented in this area after an intensive phase of TB control in 1986. METHODS: The entire population of Car Nicobar was enumerated through a house-to-house survey. Children aged <14 years were tuberculin tested and read for reaction sizes. Individuals aged >15 years were asked about the presence of chest symptoms (cough, chest pain, and unexplained fever for two weeks or longer and haemoptysis), and sputum samples were collected from patients with chest symptoms. Sputum samples were examined for presence of acid-fast bacilli. FINDINGS: Among the 4,543 children enumerated, 4,351 (95.8%) were tuberculin tested and read. Of the 981 children without bacille Calmette-Guerin scars, 161 (16.4%) were infected with TB. A total of 77 cases who were smear-positive for TB were detected from among 10,570 people aged >15 years; the observed smear-positive case prevalence was 728.5 per 100,000. The standardized prevalence of TB infection, annual risk of TB infection, and prevalence of cases smear-positive for TB were 17.0%, 2.5%, and 735.3 per 100,000, respectively. CONCLUSION: The prevalence of TB infection and smear-positive cases of TB increased significantly between 1986 and 2002. Such escalation took place despite the implementation of the national TB programme on this island, which was preceded by a set of special anti-TB measures that resulted in sputum conversion in a substantially large proportion of the smear-positive cases prevalent in the community. The most likely reason for the increase seems to be the absence of a district TB programme with enough efficiency to sustain the gains made from the one-time initial phase of special anti-TB measures. High risk of transmission of TB infection currently observed on this island calls for a drastic and sustained improvement in TB control measures.


Assuntos
Controle de Doenças Transmissíveis/organização & administração , Programas Nacionais de Saúde/organização & administração , Tuberculose Pulmonar/prevenção & controle , Adolescente , Criança , Pré-Escolar , Inquéritos Epidemiológicos , Humanos , Índia/epidemiologia , Lactente , Recém-Nascido , Área Carente de Assistência Médica , Prevalência , Avaliação de Programas e Projetos de Saúde , Fatores de Risco , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/etnologia
13.
Gene ; 315: 165-75, 2003 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-14557076

RESUMO

In vitro fusion of weakly metastatic Cloudman S91 melanoma cells with macrophages from DBA/2J mice (syngeneic with Cloudman S91 melanoma) produced hybrids with metastatic potentials ranging from low to high, with more than half showing enhanced metastasis over the parental melanoma [Clin. Exp. Metastasis 16 (1998) 299]. These hybrids, derived from the same parental fusion partners, represent a unique genetically matched model for analyzing differential gene expression regulating the metastatic phenotype. We have examined the differences in gene expression in metastatic fusion hybrid compared to its parental partners, non-/poorly metastatic melanoma cells and normal macrophages. An approach by selective polymerase chain reaction (PCR) amplification and display of 3' end restriction fragments of double-stranded cDNAs was used [Methods Enzymol. 303 (1999) 272]. Gene expression analyses showed an extensive set of transcripts that were up- or down-regulated in the most metastatic hybrid, H95-1, compared to the parental macrophages or melanoma cells. Sequence analyses of more than 60 of these differentially expressed cDNAs revealed significant up- or down-regulation of a number of genes known to be associated with metastasis of melanoma and other solid tumors. Some genes are found to express exclusively either in normal macrophages or in melanoma. Thirteen fragment sequences were found with no matches with GenBank search. Comparison of these gene expression patterns should be of great value in understanding the coordinate programs regulating metastasis. Further, the increased expression of gene(s) common in macrophage and fusion hybrids may be of importance in identifying the regulatory factor(s) related to macrophage-like trait, motility, a critical step of metastatic processes, in hybrids.


Assuntos
Proteínas de Bactérias , Perfilação da Expressão Gênica , Melanoma/genética , Animais , Sequência de Bases , Linhagem Celular Tumoral , DNA Complementar/química , DNA Complementar/genética , DNA Complementar/metabolismo , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Células Híbridas/metabolismo , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/metabolismo , Melanoma/patologia , Camundongos , Camundongos Endogâmicos DBA , Dados de Sequência Molecular , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Alinhamento de Sequência/métodos , Análise de Sequência de DNA
14.
Clin Exp Metastasis ; 20(4): 365-73, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12856724

RESUMO

GnT-V generated, beta1,6-branched polylactosamines are a common feature shared by normal granulocytes, monocytes, and a variety of malignant cells. Furthermore, activation of GnT-V in oncogenic transformation induces invasiveness and metastatic potential in mice as well as in humans. In view of the common expression of lymphocytic/monocytic trait, motility, and GnT-V by metastatic cancer cells, macrophage fusion hybrids were generated in vitro with Cloudman S91 mouse melanoma cells to test whether the parental traits are co-expressed in hybrids and how those are related to altered phenotypes in relation to metastasis. In fact, the fusion hybrids are highly metastatic in vivo, motile in vitro, and express macrophage-associated traits of increased GnT-V activity, beta1,6 branching, and polylactosamine content. A Spontaneously formed lung melanoma metastases have been identified and characterized as host x tumor hybrid containing higher DNA content than parental cells and increased GnT-V activity. The results, taken together, could reflect prior fusion of tumor-associated macrophages with cells of the primary tumor, and therefore establish a possible common link between elevated expression of GnT-V and malignant transformation, a well-known report. Moreover, the fusion hybrids with metastatic potential ranging from high to low offer a genetically matched model system, for identification and characterization of differentially expressed genes in association with metastasis, since the fusion partners are derived from the same species of mouse (DBA/2J).


Assuntos
Macrófagos/metabolismo , N-Acetilglucosaminiltransferases/fisiologia , Metástase Neoplásica/patologia , Neoplasias/metabolismo , Animais , Transformação Celular Neoplásica , Humanos , Células Híbridas , Camundongos
16.
Cell Growth Differ ; 12(12): 623-30, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11751457

RESUMO

It was shown previously that a majority of hybrids produced by in vitro fusion of normal macrophages with Cloudman S91 melanoma cells displayed enhanced metastatic potential in vivo, increased motility in vitro, increased ability to produce melanin, and responsiveness to melanocyte stimulating hormone compared with the parental Cloudman S91 melanoma cells. These hybrids also showed altered N-glycosylation consistent with a slower migration pattern of lysosome-associated membrane protein (LAMP-1) on electrophoretic gels. Because LAMP-1 is the major carrier of polylactosamine sugar structures, and synthesis of this complex sugar moiety indicates the extent of beta1,6 branch formation by beta1,6-N-acetyl-glucosaminyltransferase V (GnT-V), we analyzed the expression of GnT-V and beta1,6 branching in highly metastatic macrophage-fusion hybrids and compared with poorly metastatic ones. GnT-V was up-regulated in regard to both mRNA levels and enzymatic activity specifically in metastatic hybrids as well as parental macrophages compared with weakly metastatic hybrids and parental melanoma cells. Macrophages and metastatic hybrids also showed increased binding of the lectin L-phytohemagglutinin, which specifically binds to the beta1,6-branched sugar moiety. In addition, in metastatic hybrids there was increased cell surface expression of LAMP-1 and beta1 integrin, two prominent substrates for GnT-V also known to be associated with metastasis. Finally, exposure of metastatic hybrids in vitro to L-phytohemagglutinin or LAMP-1 completely eliminated melanocyte stimulating hormone/ isobutylmethyl xanthine-induced motility, suggesting a role for GnT-V in the motility of these cells. In summary, macrophage fusion with melanoma cells often increased metastatic potential, which was associated with enhanced expression of GnT-V and beta1,6-branching in glycoproteins. It is suggested that the known correlation with elevated GnT-V in both human and animal metastasis could, at least in some cases, reflect previous fusion of tumor cells with tumor-infiltrating macrophages, which, similar to malignant cells, show elevated expression of GnT-V and beta1,6-branched polylactosamines.


Assuntos
Células Híbridas , Macrófagos/citologia , Melanoma/metabolismo , N-Acetilglucosaminiltransferases/biossíntese , Proteínas de Plantas , Regulação para Cima , Animais , Antígenos CD/biossíntese , Northern Blotting , Linhagem Celular , Movimento Celular , DNA Complementar/metabolismo , Citometria de Fluxo , Immunoblotting , Integrina beta1/biossíntese , Proteínas de Membrana Lisossomal , Macrófagos/metabolismo , Glicoproteínas de Membrana/biossíntese , Camundongos , Metástase Neoplásica , Fito-Hemaglutininas/metabolismo , RNA/metabolismo , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Tempo , Células Tumorais Cultivadas
17.
Gene ; 275(1): 103-6, 2001 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-11574157

RESUMO

Artificial fusion of human monocyte with Cloudman S91 mouse melanoma cells resulted in hybrids that showed increased motility in vitro, enhanced metastatic potential in vivo, and also tended to be super melanotic (Rachkovsky et al., Clin. Exp. Metastasis 16 (1998) 299). However, no gene derived from monocytes has been shown to be expressed in these hybrids until now. Similar observations have also been noted in hybrids originating from mouse macrophage and mouse melanoma cells. Having the advantage of species differences in mouse x human hybrids, we are able, this time, to show by RT-PCR that some genes specific to the human genome are expressed in these hybrids, indicating that not only is the genomic DNA from parental monocytes integrated in the hybrids but also some genes are being expressed. This observation may lead us to find contributory genes from monocyte and/or macrophage that are responsible for modulating the genotypes and hence the phenotypes in the hybrids.


Assuntos
Células Híbridas/metabolismo , Melanoma/genética , Monócitos/metabolismo , Animais , Proteína Ativadora de G(M2) , Expressão Gênica , Humanos , Melanoma/patologia , Camundongos , Osteonectina/genética , Proteínas/genética , RNA/genética , RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
18.
Pest Manag Sci ; 57(3): 311-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11455663

RESUMO

A study of the toxico-kinetics, recovery percentage from different substrates, cytotoxicity and role of cytochrome P450 and b5 of liver microsome in the metabolism of deltamethrin were carried out in female black Bengal goat. The ALD50 value of deltamethrin in goat by intravenous route lies between 0.2 and 0.6 mg kg-1. Intravenous disposition kinetics using a dose of 0.2 mg kg-1 showed that the maximum blood concentration of deltamethrin was recorded at 0.5 min, followed by rapid decline, and a minimum concentration was detected at 6 min after administration. The following values were obtained: Vdarea 0.148 (+/- 0.02) litre kg-1; t1/2 (alpha) 0.22 (+/- 0.02) min; t1/2 (beta) 2.17 (+/- 0.37) min; Kel 1.05 (+/- 0.24) min-1; AUC 4.30 (+/- 0.45) micrograms min ml-1; ClB 0.05 (+/- 0.006) litre kg-1 min-1; T-B 1.93 (+/- 0.58); fc 0.40 (+/- 0.05). After 10 min, liver retained the maximum residue, and heart, adrenal gland, kidney, spleen, fat and brain also held the insecticide; liver, fat, heart and spleen retained residue after 30 min, and bone, liver and fat retained residue after 60 min of intravenous administration. Oral absorption of deltamethrin was poor and inconsistent, and approximately 65% of administered dose was recovered from faeces and gastrointestinal contents. The excretion of deltamethrin through urine was meagre, and only 0.01 and 0.013% of the administered dose was recovered after 3 and 5 days of oral administration respectively. All the tissues retained the residue after 3 days; while fat, rumen, reticulum, omasum, abomasum, large and small intestine and bone retained the residue after 5 days of oral administration; and the percentage recoveries were 1.73 and 0.027 respectively. Deltamethrin reduced the level of cytochrome P450 content of liver microsomal pellet of goat after 5 days of oral administration. Histopathological examination of liver, kidney, heart, spleen brain and lung sections of treated goats did not reveal any pathological changes.


Assuntos
Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Citocromos b5/efeitos dos fármacos , Cabras/metabolismo , Inseticidas/farmacocinética , Microssomos/efeitos dos fármacos , Piretrinas/farmacocinética , Absorção , Administração Oral , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Citocromos b5/metabolismo , Feminino , Injeções Intravenosas , Inseticidas/sangue , Inseticidas/farmacologia , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Nitrilas , Resíduos de Praguicidas/análise , Farmacocinética , Piretrinas/sangue , Piretrinas/farmacologia
19.
Proc Natl Acad Sci U S A ; 98(12): 6548-53, 2001 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-11371622

RESUMO

Cell-cell recognition often requires the formation of a highly organized pattern of receptor proteins (a synapse) in the intercellular junction. Recent experiments [e.g., Monks, C. R. F., Freiberg, B. A., Kupfer, H., Sciaky, N. & Kupfer, A. (1998) Nature (London) 395, 82-86; Grakoui, A., Bromley, S. K., Sumen, C., Davis, M. M., Shaw, A. S., Allen, P. M. & Dustin, M. L. (1999) Science 285, 221-227; and Davis, D. M., Chiu, I., Fassett, M., Cohen, G. B., Mandelboim, O. & Strominger, J. L. (1999) Proc. Natl. Acad. Sci. USA 96, 15062-15067] vividly demonstrate a complex evolution of cell shape and spatial receptor-ligand patterns (several microns in size) in the intercellular junction during immunological synapse formation. The current view is that this dynamic rearrangement of proteins into organized supramolecular activation clusters is driven primarily by active cytoskeletal processes [e.g., Dustin, M. L. & Cooper, J. A. (2000) Nat. Immunol. 1, 23-29; and Wulfing, C. & Davis, M. M. (1998) Science 282, 2266-2269]. Here, aided by a quantitative analysis of the relevant physico-chemical processes, we demonstrate that the essential characteristics of synaptic patterns observed in living cells can result from spontaneous self-assembly processes. Active cellular interventions are superimposed on these self-organizing tendencies and may also serve to regulate the spontaneous processes. We find that the protein binding/dissociation characteristics, protein mobilities, and membrane constraints measured in the cellular environment are delicately balanced such that the length and time scales of spontaneously evolving patterns are in near-quantitative agreement with observations for synapse formation between T cells and supported membranes [Grakoui, A., Bromley, S. K., Sumen, C., Davis, M. M., Shaw, A. S., Allen, P. M. & Dustin, M. L. (1999) Science 285, 221-227]. The model we present provides a common way of analyzing immunological synapse formation in disparate systems (e.g., T cell/antigen-presenting cell junctions with different MHC-peptides, natural killer cells, etc.).


Assuntos
Células Apresentadoras de Antígenos/fisiologia , Comunicação Celular , Sinapses/fisiologia , Linfócitos T/fisiologia , Animais , Antígenos de Histocompatibilidade/metabolismo , Humanos , Receptores de Antígenos de Linfócitos T/metabolismo
20.
Annu Rev Phys Chem ; 52: 537-73, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11326074

RESUMO

Driven by prospective applications, there is much interest in developing materials that can perform specific functions in response to external conditions. One way to design such materials is to create systems which, in response to external inputs, can self-assemble to form structures that are functionally useful. This review focuses on the principles that can be employed to design macromolecules that when presented with an appropriate two-dimensional surface, will self-assemble to form nanostructures that may be functionally useful. We discuss three specific examples: (a) biomimetic recognition between polymers and patterned surfaces. (b) control and manipulation of nanomechanical motion generated by biopolymer adsorption and binding, and (c) creation of patterned nanostructuctures by exposing molten diblock copolymers to patterned surfaces. The discussion serves to illustrate how polymer sequence can be manipulated to affect self-assembly characteristics near adsorbing surfaces. The focus of this review is on theoretical and computational work aimed toward elucidating the principles underlying the phenomena pertinent to the three topics noted above. However, synergistic experiments are also described in the appropriate context.

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