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1.
Phys Rev E ; 106(4-2): 045111, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36397474

RESUMEN

Modeling the electrowetting process of a liquid droplet placed on a hydrophobic surface in an ambient environment has several challenges over and above those of basic spreading [F. Mugele, Soft Matter 5, 3377 (2009)10.1039/b904493k]. At an external voltage below the value that causes contact angle saturation, transient spreading is augmented by contact angle reduction defined by the Young-Lippmann equation. In addition, the macroscopic equilibrium contact angle and, therefore, the spreading rate could be altered by the surface hysteresis. Beyond the saturation point, spreading reveals additional features of higher complexity [Q. Vo and T. Tran, J. Fluid Mech. 925, A19 (2021)10.1017/jfm.2021.677]. These details have been examined from experiments as well as numerical simulation in the present work. Below the saturation point, the contact angle model of Dwivedi et al. [Phys. Rev. Fluids 7, 034002 (2022)10.1103/PhysRevFluids.7.034002] with the correction related to the electric field is seen to be applicable. Beyond saturation, the experimentally determined instantaneous contact angle distribution shows two distinct functionalities with respect to the contact line velocity. The first prevails from the onset of spreading until the spreading factor attains a peak value. The second trend is initiated with the retraction of the contact line. Except for differences in parametric values, the form of the contact angle model remains unchanged. Simulations in the postsaturation regime are shown to match experimental data in terms of the transient spreading factor, drop shapes, and the instantaneous contact angle. The role of the ground wire is found to be important and the three-phase contact line formed on it has been included in simulations. Spreading dynamics of the droplet have also been studied when the ground wire is kept at a distance of 40 µm from the apex of the drop. Simulations as well as experiments, show the propagation of a capillary wave between the ground wire and the three-phase contact line. For spreading over an uncoated polydimethylsiloxane (PDMS) surface, the contact line is trapped at local pinning sites, leading to additional distortions in the instantaneous shapes acquired by the interface.

2.
J Immunoassay Immunochem ; 32(2): 128-33, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21391049

RESUMEN

Heat-killed Mycobacterium tuberculosis (Mtb) H37Rv-derived antigens were purified by electroelution, and their efficacy was evaluated in conferring protection against Tb in guinea pigs in order to identify those protein antigens as a subunit vaccine. A total sonicate extract of Mtb H37Rv (MTSE) was prepared by growing bacteria on Lowenstein-Jensen (LJ) solid medium to its mid-log phase, harvested, and subjected to ultrasonication. Fractions of MTSE were resolved on 10% polyacrylamide gel electrophoresis into as high (HMW, >60 kDa), middle (MMW, 31-59 kDa), and low molecular weight (LMW, <30 kDa) antigens and were purified by electroelution. The protection efficacy of each purified fraction was assessed in a placebo-controlled study by injecting them separately into a group of two animals. After two booster doses, animals were challenged on day 84, and autopsy of all animals was performed on day 126. On autopsy, animals were scored for formation of tubercles in lungs and their dissemination to organs such as spleen, liver, kidney, and lymph nodes. Viable counts (determined as colony forming unit or CFU) of lung and spleen from each animal were performed on LJ solid medium. Results of this study show that CFU of animals that received LMW antigens were significantly low with respect to control animals when compared to MMW and HMW. In conclusion, LMW of Mtb has greater potential in prevention of tubercle formation and thus could be viewed as a possible vaccine candidate in designing alternative subunit vaccines.


Asunto(s)
Antígenos Bacterianos/inmunología , Mycobacterium tuberculosis/inmunología , Tuberculosis/prevención & control , Animales , Antígenos Bacterianos/química , Modelos Animales de Enfermedad , Electroforesis en Gel de Poliacrilamida , Cobayas , Peso Molecular , Tuberculosis/inmunología
3.
Indian J Physiol Pharmacol ; 55(4): 304-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-23362721

RESUMEN

Aim of this study was to assess the effect of Self Management of Excessive Tension (SMET), a yoga based stress management program on brain wave coherence. Brain wave recordings were taken with Brain Master 2 Channel EEG (version-2.0). The subjects for the study were 72 corporate executives, 48.75 +/- 3.86 years of mean age referred from Oil and Natural Gas Corporation Limited. EEG data was recorded on the first and sixth day of 5 days SMET program. A complete statistical and spectral analysis showed 19.31% increase (p=0.03) in delta, 5.04% increase (p=0.65) in theta, 15.40% increase (p=0.09) in alpha, 1.67% decrease (p=0.54) in beta and 18.68% increase (p=0.07) in gamma wave coherence between pre and post intervention measurements. Taken together, these results suggest that participation in a SMET program was associated with improvement in emotional stability and may have implications for 'Executive Efficiency'. Because before and after designs limit inferences about intervention effects, further research is warranted to explore the effects of SMET program for stress management using a larger, randomized controlled trial.


Asunto(s)
Ondas Encefálicas , Encéfalo/fisiología , Yoga , Adulto , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad
4.
Metabolism ; 115: 154458, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33278413

RESUMEN

BACKGROUND: Polycystic ovary syndrome (PCOS) is often associated with higher levels of LH, and arrested ovarian follicular growth. The direct impact of high LH on FSH mediated metabolic responses in PCOS patients is not clearly understood. METHOD: In order to investigate the impact of FSH and LH on glucose metabolism in preovulatory granulosa cells (GCs), we used [U14C]-2 deoxyglucose, D-[U14C]-glucose or 2-NBD glucose to analyse glucose uptake and its incorporation into glycogen. To reproduce the high androgenic potential in PCOS patients, we administered hCG both in vitro and in vivo. The role of IRS-2/PI3K/Akt2 pathway was studied after knockdown with specific siRNA. Immunoprecipitation and specific assays were used for the assessment of IRS-2, glycogen synthase and protein phosphatase 1. Furthermore, we examined the in vivo effects of hCG on FSH mediated glycogen increase in normal and PCOS rat model. HEK293 cells co-expressing FSHR and LHR were used to demonstrate glucose uptake and BRET change by FSH and hCG. RESULTS: In normal human and rat granulosa cells, FSH is more potent than hCG in stimulating glucose uptake, however glycogen synthesis was significantly upregulated only by FSH through increase in activity of glycogen synthase via IRS-2/PI3K/Akt2 pathway. On the contrary, an impaired FSH-stimulated glucose uptake and glycogen synthesis in granulosa cells of PCOS-patients indicated a selective defect in FSHR activation. Further, in normal human granulosa cells, and in immature rat model, the impact of hCG on FSH responses was such that it inhibited the FSH-mediated glucose uptake as well as glycogen synthesis through inhibition of FSH-stimulated IRS-2 expression. These findings were further validated in HEK293 cells overexpressing Flag-LHR and HA-FSHR, where high hCG inhibited the FSH-stimulated glucose uptake. Notably, an increased BRET change was observed in HEK293 cells expressing FSHR-Rluc8 and LHR-Venus possibly suggesting increased heteromerization of LHR and FSHR in the presence of both hCG and FSH in comparison to FSH or hCG alone. CONCLUSION: Our findings confirm a selective attenuation of metabolic responses to FSH such as glucose uptake and glycogen synthesis by high activation level of LHR leading to the inhibition of IRS-2 pathway, resulting in depleted glycogen stores and follicular growth arrest in PCOS patients.


Asunto(s)
Hormona Folículo Estimulante/farmacología , Glucosa/metabolismo , Células de la Granulosa/efectos de los fármacos , Hormona Luteinizante/farmacología , Síndrome del Ovario Poliquístico/metabolismo , Animales , Modelos Animales de Enfermedad , Estradiol/farmacología , Femenino , Células de la Granulosa/metabolismo , Células HEK293 , Humanos , Proteínas Sustrato del Receptor de Insulina/metabolismo , Ratas
5.
J Transl Med ; 8: 43, 2010 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-20433757

RESUMEN

BACKGROUND: Photodynamic therapy (PDT) involves excitation of sensitizer molecules by visible light in the presence of molecular oxygen, thereby generating reactive oxygen species (ROS) through electron/energy transfer processes. The ROS, thus produced can cause damage to both the structure and the function of the cellular constituents resulting in cell death. Our preliminary investigations of dose-response relationships in a human glioma cell line (BMG-1) showed that disulphonated aluminum phthalocyanine (AlPcS2) photodynamically induced loss of cell survival in a concentration dependent manner up to 1 microM, further increases in AlPcS2concentration (>1 microM) were, however, observed to decrease the photodynamic toxicity. Considering the fact that for most photosensitizers only monotonic dose-response (survival) relationships have been reported, this result was unexpected. The present studies were, therefore, undertaken to further investigate the concentration dependent photodynamic effects of AlPcS2. METHODS: Concentration-dependent cellular uptake, sub-cellular localization, proliferation and photodynamic effects of AlPcS2 were investigated in BMG-1 cells by absorbance and fluorescence measurements, image analysis, cell counting and colony forming assays, flow cytometry and micronuclei formation respectively. RESULTS: The cellular uptake as a function of extra-cellular AlPcS2 concentrations was observed to be biphasic. AlPcS2 was distributed throughout the cytoplasm with intense fluorescence in the perinuclear regions at a concentration of 1 microM, while a weak diffuse fluorescence was observed at higher concentrations. A concentration-dependent decrease in cell proliferation with accumulation of cells in G2+M phase was observed after PDT. The response of clonogenic survival after AlPcS2-PDT was non-monotonic with respect to AlPcS2 concentration. CONCLUSIONS: Based on the results we conclude that concentration-dependent changes in physico-chemical properties of sensitizer such as aggregation may influence intracellular transport and localization of photosensitizer. Consequent modifications in the photodynamic induction of lesions and their repair leading to different modes of cell death may contribute to the observed non-linear effects.


Asunto(s)
Glioma/tratamiento farmacológico , Glioma/patología , Indoles/uso terapéutico , Compuestos Organometálicos/uso terapéutico , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Clonales , Daño del ADN , Humanos , Indoles/metabolismo , Indoles/farmacología , Compuestos Organometálicos/metabolismo , Compuestos Organometálicos/farmacología , Fármacos Fotosensibilizantes/farmacología , Fracciones Subcelulares/efectos de los fármacos , Fracciones Subcelulares/metabolismo , Factores de Tiempo
6.
J Clin Monit Comput ; 24(2): 155-9, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20229061

RESUMEN

INTRODUCTION: Thoracic electrical bioimpedance (TEB) for measuring cardiac output (CO) is being explored increasingly as an alternative to pulmonary artery catheter. The major advantage of this technology is that it is non-invasive and easy to perform. Several studies have compared it to thermodilution cardiac output using PA catheter, with variable correlation. Multigated radionuclide equilibrium cardiography (RNEC) method of cardiac output measurement is known to be reliable. OBJECTIVE: To compare cardiac output measured by thoracic electrical bioimpdenace with that measured by multigated radionuclide equilibrium cardiography. PATIENTS AND METHODS: CO studies were performed sequentially at a single sitting by TEB and RNEC methods among patients with cardiac symptoms referred for radionuclide study as part of their evaluation. TEB CO was measured by placing two pairs of electrodes on either side of neck and two other pairs on either side of the lower chest. Stroke volume was estimated from the sequential changes in transthoracic electrical bioimpedance induced by rhythmic aortic blood flow, using Kubicek equation. RNEC-CO was measured by intravenous injection of radio-active Technitium-tagged RBCs followed by ECG gated blood pool imaging over the chest (MUGA study). Bland-Altman analysis was used to compare the measurements. RESULTS: A total of 32 subjects with proven or suspected ischemic heart disease, but without overt cardiac failure, edema or arrhythmias were studied (M:F::26:6; mean age: 48 +/- 12 years). The mean TEB-CO was 3.54 +/- 1.052 l/min and mean RNEC-CO was 3.907 +/- 0.952 l/min. Correlation coefficient (r) for these measurements was 0.67 (p < 0.01), with bias: -0.421 l/min; precision: 1.557 l/min; and percentage error of measurement: 42.35%. CONCLUSIONS: This study observed a moderate correlation between TEB and RNEC methods of CO measurement. Further studies are indicated to explore the relative utility of TEB in comparison with RNEC as well as other methods of CO measurement before considering its use in patients with ischemic heart disease.


Asunto(s)
Gasto Cardíaco , Tomografía Computarizada por Emisión de Fotón Único Sincronizada Cardíaca/métodos , Cardiografía de Impedancia/métodos , Disfunción Ventricular Izquierda/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
7.
Trans Indian Natl Acad Eng ; 5(2): 251-254, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-38624456

RESUMEN

The ongoing viral outbreak labeled COVID-19 is spreading rapidly across states and is posing a great threat to public health. Rapid identification of the virus in the population plays a crucial role in isolating the individual and breaking the transmission chain, apart from initiating an appropriate treatment procedure. Here, we discuss an electrowetting-on-dielectric (EWOD) technology that uses a microprocessor-controlled electrode array to merge a possibly infected sample carried by a liquid drop with a drop of a reagent to carry out the testing process. Changes in color occurring during the mixing process of the drops are imaged using a camera.

8.
Cell Microbiol ; 10(6): 1286-303, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18248626

RESUMEN

Mycobacterium tuberculosis H37Rv (Mtb) excludes phagocyte oxidase (phox) and inducible nitric oxide synthase (iNOS) while preventing lysosomal fusion in macrophages (MPhis). The antigen 85A deficient (Delta fbpA) mutant of Mtb was vaccinogenic in mice and the mechanisms of attenuation were compared with MPhis infected with H37Rv and BCG. Delta fbpA contained reduced amounts of trehalose 6, 6, dimycolate and induced minimal levels of SOCS-1 in MPhis. Blockade of oxidants enhanced the growth of Delta fbpA in MPhis that correlated with increased colocalization with phox and iNOS. Green fluorescent protein-expressing strains within MPhis or purified phagosomes were analysed for endosomal traffick with immunofluorescence and Western blot. Delta fbpA phagosomes were enriched for rab5, rab11, LAMP-1 and Hck suggesting enhanced fusion with early, recycling and late endosomes in MPhis compared with BCG or H37Rv. Delta fbpA phagosomes were thus more mature than H37Rv or BCG although, they failed to acquire rab7 and CD63 preventing lysosomal fusion. Finally, Delta fbpA infected MPhis and dendritic cells (DCs) showed an enhanced MHC-II and CD1d expression and primed immune T cells to release more IFN-gamma compared with those infected with BCG and H37Rv. Delta fbpA was thus more immunogenic in MPhis and DCs because of an enhanced susceptibility to oxidants and increased maturation.


Asunto(s)
Aciltransferasas/genética , Antígenos Bacterianos/genética , Células Dendríticas/metabolismo , Macrófagos/metabolismo , Mycobacterium tuberculosis/fisiología , Óxido Nítrico Sintasa de Tipo II/metabolismo , Oxidorreductasas/metabolismo , Fagosomas/metabolismo , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Secuencias Repetidas Terminales/genética , Animales , Antígenos CD1/metabolismo , Antígenos CD1d , Células Cultivadas , Células Dendríticas/microbiología , Endosomas/metabolismo , Proteínas de Unión al GTP/metabolismo , Antígenos de Histocompatibilidad Clase II/metabolismo , Interferón gamma/biosíntesis , Proteínas de Membrana de los Lisosomas/metabolismo , Macrófagos/microbiología , Ratones , Ratones Endogámicos C57BL , Mycobacterium tuberculosis/patogenicidad , Mutación Puntual , Proteínas Proto-Oncogénicas c-hck/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Proteína 1 Supresora de la Señalización de Citocinas , Linfocitos T/inmunología , Linfocitos T/metabolismo , Tuberculosis/inmunología , Tuberculosis/microbiología , Proteínas de Unión al GTP rab5/metabolismo
9.
Phytochem Anal ; 19(2): 99-103, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17654521

RESUMEN

A new staining method for urease activity in non-denaturing polyacrylamide gels is described. The increase in local pH of the gel, resulting from ureolytic activity of urease, causes a purple red coloured band after incubation of the polyacrylamide gel with urea. Staining of urease activity using this method is very specific for catalytically active urease even in crude preparations. Detection of urease activity by this method is rapid, simple and economical. The described method is also more sensitive than existing methods of urease staining. A minimum of 0.25 mU of urease activity can be detected after 5 min of incubation with the substrate. The method has been used to demonstrate the presence of different charge isoforms of urease in a member of the plant family Cucurbitaceae.


Asunto(s)
Electroforesis en Gel de Poliacrilamida/métodos , Nitroprusiato/metabolismo , Coloración y Etiquetado/métodos , Compuestos de Sulfhidrilo/metabolismo , Ureasa/análisis , Ureasa/metabolismo , Sensibilidad y Especificidad
10.
J Clin Monit Comput ; 22(3): 175-80, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18418719

RESUMEN

OBJECTIVE: Thoracic electrical bioimpedance (TEB) cardiac output (CO) is being explored increasingly as a non-invasive alternative to the pulmonary artery catheter (PAC). This study compared TEB-CO measured using a new instrument--NICOMON (Larsen & Toubro Ltd. India) with thermodilution (Td) CO in post-cardiac surgery patients. METHODS: Postoperative cardiac surgical patients requiring a PAC for their management were studied. TEB-CO was measured by passing a 4 mA RMS alternating current across the chest and measuring the analog bioimpedence across the thorax. Kubicek equation was used to estimate TEB-CO. Td-CO was measured using a PAC. Bland-Altman analysis was used to compare paired data. RESULTS: One hundred and ninety-seven pairs of CO measurements were made by the two methods among 35 patients. Mean TEB-CO was 5.15 +/- 1.27 l/min and mean Td-CO was 5.22 +/- 1.28 l/min. Pearson correlation coefficient (r) for these measurements was 0.856 (P < 0.01), with bias -0.0651 l and precision: +/-1.37 l/min. The percentage error of measurement of this precision was 26.44%. Cardiac index also correlated among the two methods (r = 0.789; P = 0.01). CONCLUSIONS: Thoracic electrical bioimpedance cardiac output compares favorably with thermodilution method among post-cardiac surgery patients. Further studies are indi- cated with this instrument to validate its efficacy in various clinical situations and utility in monitoring hemodynamic interventions.


Asunto(s)
Gasto Cardíaco , Cardiografía de Impedancia/métodos , Diagnóstico por Computador/métodos , Cardiopatías/diagnóstico , Cardiopatías/cirugía , Termodilución/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Cardiopatías/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Cuidados Posoperatorios/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
11.
Clin Chim Acta ; 376(1-2): 52-9, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16959230

RESUMEN

BACKGROUND: Peptides and proteins have both sequence-specific (contiguous) and conformation-specific (discontiguous) epitopes. Sequence-specific epitopes are delineated by peptide approach and other robust methods like competition assays, gene expression assays, synthetic peptide library based assays etc. Available methods for delineation of conformation-specific epitopes are cumbersome (X-ray crystallography etc.), time-consuming and require costly sophisticated equipments. Hence, there is a need to develop a simple method for identification and mapping of conformation-specific epitopes. METHOD: In the single-step solid phase radioimmunoassay (SS-SPRIA), an immunochemical bridge of 'mouse IgG-anti-mouse IgG' was prepared in the polypropylene wells followed by adsorption with hCG specific monoclonal antibody (MAb) G(1)G(10).1. The extent of competitive inhibition in binding ability of (125)IhCG-beta with chemically or enzymatically modified hCG-beta to immobilized MAb G(1)G(10).1 in comparison to hCG-beta standards was utilized to identify the epitopic amino acid involved in epitope-paratope interaction. RESULTS: Data clearly suggest that the epitope under investigation consisted of Arg (94, 95) and Asp (99) at the core region with a Lys (104) and a His (106) in the proximity and absence of chymotrypsin susceptible Phe or Tyr in this region. CONCLUSION: The data of SS-SPRIA revealed the 93-100 loop of amino acid sequence, as the core region of conformation-specific epitope of hCG-beta at or near the receptor-binding region. Hence, SS-SPRIA seems to be a simple method for identification and mapping of conformation-specific epitopes.


Asunto(s)
Gonadotropina Coriónica Humana de Subunidad beta/química , Gonadotropina Coriónica Humana de Subunidad beta/inmunología , Mapeo Epitopo/métodos , Epítopos/inmunología , Radioinmunoensayo/métodos , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/química , Humanos , Ratones , Datos de Secuencia Molecular
12.
Dermatoendocrinol ; 9(1): e1395537, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29484103

RESUMEN

There is a rise in number of people diagnosed with Diabetes Mellitus. The incidence is rising in modern Indian society because of Industrial development and drastically changing lifestyles. Diabetic neuropathies are microvascular disorders that are usually associated with the duration of Diabetes. Among the various forms, the most common is Diabetic Peripheral Neuropathy. The disease if neglected leads to chronic ulcer formation leading to amputations frequently. Hence the aim of this study is to document the early cutaneous changes and create an early awareness in the importance of controlling Diabetes. The study consisted of 205 patients with Type 2 DM. Participant's neuropathy status was determined based on Neuropathy Disability Score and Diabetic Neuropathy Symptom Score. Among the Skin changes documented, the common changes seen were: Peripheral hair loss in 185 (90.2%), Xerosis in 168 (82%), Anhydrosis in 162 (79%), Plantar Fissures in 136 (66.3%), Plantar Ulcer in 80 (39%), common nail changes documented were Onychomycosis in 165 (80.5%) and Onychauxis in 53 (25.8%) patients in relation to the occupation and duration of Diabetes mellitus. In conclusion, it is important to control glycemic levels in the all stages of Diabetes and institute foot care measures to prevent the complications of neuropathy.

13.
FEMS Immunol Med Microbiol ; 47(1): 134-7, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16706796

RESUMEN

A modified passive hemagglutination using double aldehyde stabilized cells (tanned sheep erythrocytes treated with glutaraldehyde and pyruvic aldehyde) was evaluated for detection of both antimycobacterial antibodies and circulating mycobacterial antigens simultaneously in human serum samples from patients with pulmonary tuberculosis (n=40) and a control group (n=44). Double aldehyde stabilized cells sensitized with an optimum dose of 200 microg mL(-1) of sonicate extract of Mycobacterium tuberculosis antigens was used as single probe to detect both antibodies and antigen, respectively, by passive hemagglutination and passive hemagglutination inhibition. The sensitivity limit of passive hemagglutination inhibition was determined to be 280 ng mL(-1) using a dose-response curve. Sensitivity of passive hemagglutination and passive hemagglutination inhibition, respectively, was 90% and 52.5%, and specificity was 91% and 100%. Although passive hemagglutination and passive hemagglutination inhibition need further evaluation, these erythrocyte-based immunoassays are potentially advantageous, especially as double aldehyde stabilized sensitized cells could be used as a single probe for detection of both antibodies and antigen. In addition, erythrocyte-based immunoassays are rapid, simple and cost-effective with a high degree of sensitivity.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/sangre , Eritrocitos/inmunología , Mycobacterium tuberculosis/inmunología , Tuberculosis Pulmonar/inmunología , Animales , Relación Dosis-Respuesta Inmunológica , Eritrocitos/química , Hemaglutinación , Pruebas de Inhibición de Hemaglutinación , Humanos , Inmunoensayo/métodos , Conejos , Ovinos , Tuberculosis Pulmonar/sangre
14.
J Med Phys ; 40(3): 144-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26500400

RESUMEN

To study the behavior of Acuros XB algorithm for flattening filter free (FFF) photon beams in comparison with the anisotropic analytical algorithm (AAA) when applied to homogeneous and heterogeneous phantoms in conventional and RapidArc techniques. Acuros XB (Eclipse version 10.0, Varian Medical Systems, CA, USA) and AAA algorithms were used to calculate dose distributions for both 6X FFF and 10X FFF energies. RapidArc plans were created on Catphan phantom 504 and conventional plans on virtual homogeneous water phantom 30 × 30 × 30 cm(3), virtual heterogeneous phantom with various inserts and on solid water phantom with air cavity. Dose at various inserts with different densities were measured in both AAA and Acuros algorithms. The maximum % variation in dose was observed in (-944 HU) air insert and minimum in (85 HU) acrylic insert in both 6X FFF and 10X FFF photons. Less than 1% variation observed between -149 HU and 282 HU for both energies. At -40 HU and 765 HU Acuros behaved quite contrarily with 10X FFF. Maximum % variation in dose was observed in less HU values and minimum variation in higher HU values for both FFF energies. Global maximum dose observed at higher depths for Acuros for both energies compared with AAA. Increase in dose was observed with Acuros algorithm in almost all densities and decrease at few densities ranging from 282 to 643 HU values. Field size, depth, beam energy, and material density influenced the dose difference between two algorithms.

15.
J Cancer Res Ther ; 11(1): 136-40, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25879351

RESUMEN

AIM OF STUDY: The purpose of this study was to report the dosimetric characteristics of the small fields in flattening filter free (FFF) beams (output measurements, profile analysis, surface dose and consistency) generated by medical linear accelerator and its variation with respect to flattened beams (FB). MATERIALS AND METHODS: Surface doses were obtained for field sizes 1 × 1-40 × 40 cm(2). Field width and penumbra were analyzed for field sizes 1 × 1-40 × 40 cm(2). To take output factors for small fields, diode and micro chamber were used and data was taken at a source-to-surface distance (SSD) and extended SSD. Consistency checked for the dosimetric data for 1 year. RESULTS: Surface doses were higher in FFF compared with FB up to 20 × 20 cm(2) field size. Measured field sizes were slightly lesser in FFF and penumbra values were increased with respect to field size in both FB and FFF. For small fields, diode values have shown more promising results than micro chamber. Small field output measurements at nominal SSD and extended SSD were well in agreement with each other. FFF beams showed good data consistency in 1 year duration. CONCLUSION: Small field dosimetry, surface dose, profile analysis and consistency of FFF beams in FFF photon beams were derived and data shown good consistency during 1 year duration.


Asunto(s)
Aceleradores de Partículas , Radiometría/métodos , Humanos , Dosificación Radioterapéutica
16.
Endocrinology ; 100(4): 1137-42, 1977 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-319994

RESUMEN

The mechanism whereby the reciprocal relationship between the plasma levels of prolactin and HL is maintained in lactating rats under different degrees of suckling stimulus has been investigated in the present study. Plasma levels of luteinizing hormone (LH) in lactating rats suckling two pups could be reduced significantly by injecting prolactin (PRL). This reduction was also evident in ovariectomized and ovariectomized-adrenalectomized lactating rats, thus excluding mediation of the inhibitory effect by steroids from end-organs. The in vivo response of the pituitary to exogenous LHRH was lower in rats suckling eight pups than those suckling two pups. Prolactin administered prior to LHRH caused an inhibition of the response of the pituitary to exogenous LHRH in rats suckling two pups. These data provide evidence for the hypothesis that in the lactating rat, in the presence of minimal suckling stimulus, the causative factor for reducing serum LH levels is prolactin, which acts by altering the pituitary responsiveness to LHRH.


Asunto(s)
Lactancia , Hormona Luteinizante/sangre , Prolactina/farmacología , Adrenalectomía , Animales , Femenino , Hormona Liberadora de Gonadotropina/farmacología , Lactancia/efectos de los fármacos , Tamaño de la Camada , Ovario/fisiología , Hipófisis/efectos de los fármacos , Embarazo , Ratas , Conducta en la Lactancia
17.
FEBS Lett ; 242(1): 139-43, 1988 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-2849557

RESUMEN

When the metabolically obtained 35S-labelled sheep pituitary prolactin-rich fraction was subjected to chemical deglycosylation the radioactivity was retained in the immunoprecipitable prolactin. 35S-labelled prolactin-rich pituitary extract was fractionated on SDS-PAGE and protein was extracted from prolactin positive bands. When the extracted 35S-labelled prolactin was hydrolysed by alkali and then chromatographed on a thin layer of silica, it showed the presence of a radioactive compound which had an Rf value identical to the standard Tyr-O-SO4 synthesized and characterized in our laboratory.


Asunto(s)
Hipófisis/análisis , Prolactina/análisis , Tirosina/análogos & derivados , Animales , Cromatografía en Capa Delgada , Electroforesis en Gel de Poliacrilamida , Glicosilación , Técnicas de Inmunoadsorción , Mesilatos , Prolactina/metabolismo , Ovinos , Espectrofotometría Ultravioleta , Sulfatos/metabolismo , Radioisótopos de Azufre , Tirosina/análisis
18.
FEBS Lett ; 154(2): 301-4, 1983 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-6832373

RESUMEN

The terminal hexosamines of bovine pituitary lutropin are thought to contain a sulfate moiety. In order to test this, a biosynthetic approach was adopted. When rat and buffalo (bovine) pituitaries were incubated with radioactive 35SO4(2-) for 2 h in vitro it was observed that radioactivity test incorporated into trichloroacetic acid-precipitable proteins. When the radioactive proteins were treated with an anti-sheep lutropin serum, radioactivity was found in the immunoprecipitate. The incorporation into rat lutropin like material was very marginal while it was very significant in the case of buffalo lutropin.


Asunto(s)
Hormona Luteinizante/metabolismo , Hipófisis/metabolismo , Sulfatos/metabolismo , Animales , Búfalos , Conejos , Ratas , Ovinos , Especificidad de la Especie
19.
Neuroscience ; 15(3): 887-90, 1985 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2415874

RESUMEN

The functional significance of the production of ammonia during neuronal activity is not known, although a number of studies are available concerning the mechanism of of ammonia toxicity in brain. Hyperammonemia without behavioural change was induced in experimental rats by i.p. administration of either a single dose of ammonium acetate or 6 doses with an interval of 1 h during the day or one single dose daily for 7 days. No significant change was observed in the content of DNA, RNA and protein in cerebral cortex, cerebellum and brain stem following the administration of a single dose. There was a marked decreased in the content of DNA in all three brain regions after the administration of 6 hourly doses of ammonium acetate. Under these conditions the RNA was found to increase in all three brain regions. A decrease in the content of protein per gram wet weight was observed in cerebral cortex and brain stem while the change in cerebellum was found to be insignificant. However, the content of RNA and protein was found to show a very significant increase when expressed per microgram of DNA for each region under these conditions, indicating an increase in RNA and protein in the cells surviving the toxic damage caused by ammonia. A marked and significant increase in the content of RNA and protein was observed in all three brain regions following the administration of a single dose per day for 7 days. These results are discussed not only with respect to toxic damage to the glial cells by ammonia, but also with respect to the probable effect of ammonia liberated during neuronal activity on inhibition of lysosomal degradation of protein, and on its stimulatory effects of transcriptional and translational activities. The increased RNA and protein under these conditions may be contributing not only in the proliferation of glial cells (Alzheimer Type II cells) but also in the dendritic spinous growth.


Asunto(s)
Acetatos/farmacología , Química Encefálica/efectos de los fármacos , ADN/análisis , Proteínas del Tejido Nervioso/análisis , ARN/análisis , Amoníaco/metabolismo , Animales , Encéfalo/metabolismo , Tronco Encefálico/análisis , Cerebelo/análisis , Corteza Cerebral/análisis , Femenino , Masculino , Ratas
20.
Cancer Lett ; 93(2): 201-5, 1995 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-7621429

RESUMEN

Changes in the expression of two proto-oncogenes, c-jun and c-Ha-ras and their modulation by MPG were studied in regenerating rat liver. A significant increase in c-jun and c-Ha-ras mRNA levels was noted after partial hepatectomy. However, the increase in c-Ha-ras mRNA was much less when compared with c-jun mRNA levels. Metallothionein (MT-I) mRNA levels showed a gradual decrease following partial hepatectomy. However, the decrease in MT-I mRNA levels was not significant when intertime comparisons were made. MPG caused a significant reduction in the levels of c-jun and c-Ha-ras mRNA in the regenerating rat liver compared to untreated controls, but had very little effect on MT-I mRNA levels. Selective reduction in the expression of proto-oncogenes by MPG suggests that MPG may affect the cell proliferation by modulating the expression of these genes.


Asunto(s)
Genes jun/efectos de los fármacos , Genes ras/efectos de los fármacos , Regeneración Hepática/fisiología , Proteínas Proto-Oncogénicas c-jun/efectos de los fármacos , Tiopronina/farmacología , Proteínas ras/efectos de los fármacos , Animales , Regulación de la Expresión Génica/efectos de los fármacos , Regeneración Hepática/genética , Metalotioneína/metabolismo , Proteínas Proto-Oncogénicas c-jun/metabolismo , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Factores de Tiempo , Proteínas ras/metabolismo
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