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1.
Eur J Investig Health Psychol Educ ; 13(6): 1097-1116, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37366787

RESUMEN

Sustainability and environmental concerns have become increasingly important in the business world, with organizations seeking to integrate sustainable practices and enhance their brand citizenship behavior. Servant leadership that is focused on the environment is a type of leadership approach that gives prominence to preserving and promoting environmental sustainability. This study aims to examine the impact of environmentally specific servant leadership on brand citizenship behavior, with a focus on the mediating roles of green-crafting behavior and employee-identified meaningful work. Drawing on data from a survey of 319 employees working in hotels, this study conducted partial least square-structural equation modeling (PLS-SEM) to test a dual-moderated mediation model to explore the direct and indirect effects of environmentally specific servant leadership on brand citizenship behavior. The results of this study reveal that environmentally specific servant leadership has a significant and positive impact on green-crafting behavior and employee meaningful work. Moreover, green-crafting behavior and employee-perceived meaningful work both mediate the link between environmentally specific servant leadership and brand citizenship behavior. Specifically, green-crafting behavior acts as a mediator between environmentally specific servant leadership and employee-perceived meaningful work, while employee-perceived meaningful work mediates the link between green-crafting behavior and brand citizenship behavior. These findings have important implications for managers and organizations that seek to enhance their sustainability and brand citizenship behavior. Specifically, this study highlights the critical role of environmentally specific servant leadership (ESSL) in promoting green-crafting behavior and employee-perceived meaningful work, which in turn influence brand citizenship behavior. Therefore, organizations can improve their brand citizenship performance by developing ESSL behaviors and practices that foster green-crafting behavior and employee-perceived meaningful work.

2.
Sci Rep ; 13(1): 4407, 2023 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-36928359

RESUMEN

Carrion flies play a significant role in forensic entomotoxicology, where they are employed as alternative samples when traditional samples are unavailable. In situations of poisoned death, these toxins disrupt insect development and affect forensic entomology analyses. So, forensic entomotoxicologists must be aware of this impact. The present study aimed to determine the effects of aluminum phosphide (AlP) and cypermethrin (CP) on the biochemical parameters and antioxidant enzymes of the third instar of Chrysomya megacephala maggots. C. megacephala was reared on normal and poisoned rabbit carcasses with aluminum phosphide and cypermethrin. The third larval instar of C. megacephala was studied using by spectrophotometer for detection of total protein, (TP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), total antioxidant capacity (TAC), superoxide dismutase (SOD), glutathione s-transferase (GST), catalase (CAT) and malondialdehyde (MDA). The results indicated to significantly decrease of TP, TAC, SOD, GST and CAT and increase of AST, ALT and MDA in the maggots reared on the poisoned carcasses with AlP or CP compared with control group. In conclusion, the tested insecticides brought about a decrease antioxidant enzyme activity and increase of MDA could be involved in free radicals in C. megacephala larvae leading to oxidative stress by these insecticidal components.


Asunto(s)
Antioxidantes , Insecticidas , Animales , Conejos , Larva/fisiología , Antioxidantes/farmacología , Calliphoridae , Insecticidas/farmacología , Cadáver , Superóxido Dismutasa/farmacología
3.
Clin Lab ; 68(12)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36546756

RESUMEN

BACKGROUND: Uterine receptivity and implantation are complex processes requiring coordinated expression of molecules by zygote and uterus. Leukemia inhibitory factor (LIF) is one of the most important cytokines in the reproductive tract. Without expression of LIF in the uterus, implantation of a blastocyst cannot begin. Our objectives were to measure the leukemia inhibitory factor (LIF) concentration in serum with or without endometrial scratch-ing in women with unexplained infertility. METHODS: This study is a randomized control trial, carried out at the infertility clinic of Qena University hospital, South Valley University, Egypt. The study included 200 women with unexplained infertility divided into two groups: Group 1 included 100 patients undergoing endometrial scratching at mid luteal phase. Group 2 included 100 patients undergoing expectant management. Serum leukemia inhibitory factor (LIF) concentration was measured at mid-luteal phase of cycle and follow up of pregnancy occurrence in both groups. RESULTS: LIF was significantly higher in the group of endometrial scratching compared to group 2. LIF was significantly higher in pregnant women compared to non-pregnant ones in both the endometrial scratching group and group 2. For the endometrial scratching group, LIF was a significant marker for successful implantation at cutoff point of 97.2 with sensitivity of 97.3% and specificity of 77.8% while PPV was 72% and NPV was 98. CONCLUSIONS: Endometrial scratching was associated with higher level of LIF and pregnancy rate. LIF was significantly higher in pregnant women with or without endometrial scratching.


Asunto(s)
Infertilidad Femenina , Femenino , Embarazo , Humanos , Infertilidad Femenina/diagnóstico , Infertilidad Femenina/terapia , Infertilidad Femenina/metabolismo , Factor Inhibidor de Leucemia/metabolismo , Implantación del Embrión , Endometrio/metabolismo , Egipto
4.
Diabet Med ; 39(10): e14911, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35789029

RESUMEN

INTRODUCTION: The effects of the COVID-19 pandemic on mental health have been profound. Mental health and diabetes self-care are inter-related. We examined whether COVID-19 anxiety, depressive symptoms and health anxiety were associated with domains of diabetes self-management and investigated whether greater COVID-19 anxiety syndrome would independently contribute to suboptimal diabetes self-care. RESEARCH DESIGN AND METHODS: Surveys were sent to people attending diabetes clinics of three London hospitals. Participants completed the Diabetes Self-Management Questionnaire (DSMQ), the COVID-19 Anxiety Syndrome Scale (C-19 ASS), which measures perseveration and avoidant maladaptive coping behaviour, assessed with measures of co-existent depressive symptoms and anxiety, controlling for age, gender and social deprivation. Clinical data, including pre- and post-lockdown HbA1c measures, were obtained from hospital records for 369 respondents, a response rate of 12.8%. RESULTS: Depressive symptom scores were high. Both pre-existing health anxiety and depressive symptoms were independently linked to improvable measures of diabetes care, as was lower socio-economic rank. However, avoidant COVID-19 anxiety responses were independently associated with higher diabetes self-care scores. HbA1c levels improved modestly over the year of UK lockdown in this cohort. CONCLUSION: During the height of lockdown, avoidant coping behaviours characteristic of the COVID-19 anxiety syndrome may in fact work to improve diabetes self-care, at least in the short term. We recommend screening for depressive symptoms and being aware of the significant minority of people with COVID-19 anxiety syndrome who may now find it difficult to re-engage with face-to-face clinic opportunities.


Asunto(s)
COVID-19 , Diabetes Mellitus , Automanejo , Ansiedad/epidemiología , Ansiedad/psicología , COVID-19/epidemiología , Control de Enfermedades Transmisibles , Depresión/epidemiología , Depresión/psicología , Depresión/terapia , Humanos , Pandemias
5.
Naunyn Schmiedebergs Arch Pharmacol ; 395(2): 227-246, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34994822

RESUMEN

Combination therapy comprising natural polyphenols and anticancer drugs has been used to decrease the adverse effects and increase the effectiveness and antioxidant activities of the drugs. The antioxidant and anticancer effects of quercetin (Q), a nutritive polyphenol, have been observed both in vitro and in vivo. Likewise, the anticancer activity of sulfamethoxazole (S) has been demonstrated in vitro and in vivo. This study aimed to investigate the in vitro and in vivo anticancer effects of Q alone and in combination with S. The in vitro effects of S, Q, and S + Q on HCT-116, HepG2, MCF-7, and PC3 cell lines were examined. Additionally, the in vivo effects of these drugs were evaluated using Ehrlich ascites carcinoma (EAC) tumor-bearing mice. The in vitro data revealed the potent anticancer activity of S + Q through the induction of apoptosis and cell cycle arrest. The EAC-inoculated mice treated with S + Q presented with elevated SOD, GSH, CAT, and TAC levels and decreased malondialdehyde levels compared with the untreated EAC group, thus revealing the antioxidant and protective actions of S + Q against EAC cell invasion. Furthermore, the downregulation of NFkB and upregulation of the caspase3 gene in the EAC-inoculated mice treated with the S + Q indicated the induction of the apoptotic pathway and decrease in both cell proliferation and metastasis. In conclusion, the combination of S and Q might exert anticancer effects by inducing apoptosis and exhibiting selective toxicity against the cancer cells and thereby protecting the vital organs.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Carcinoma de Ehrlich/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HCT116 , Células Hep G2 , Humanos , Células MCF-7 , Ratones , FN-kappa B/metabolismo , Células PC-3 , Quercetina/administración & dosificación , Sulfametoxazol/administración & dosificación
6.
Front Neurosci ; 15: 640648, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33679318

RESUMEN

In addition to essential micronutrients such as vitamin C, citrus fruits represent a considerably rich source of non-essential bioactive compounds, in particular flavanones which form a sub-set of the flavonoid group. Preclinical studies have demonstrated the neuroprotective potential of citrus flavonoids and have highlighted both the well-established (anti-inflammatory and anti-oxidative properties), and newly emerging (influence upon blood-brain barrier function/integrity) mechanistic actions by which these neurological effects are mediated. Encouragingly, results from human studies, although limited in number, appear to support this preclinical basis, with improvements in cognitive performance and disease risk observed across healthy and disease states. Therefore, citrus fruits - both as whole fruit and 100% juices - should be encouraged within the diet for their potential neurological benefit. In addition, there should be further exploration of citrus polyphenols to establish therapeutic efficacy, particularly in the context of well-designed human interventions.

7.
J Intern Med ; 289(2): 247-254, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33259680

RESUMEN

BACKGROUND: We aimed to study the effect of social containment mandates on ACS presentation during COVID-19 pandemic using location activity and mobility data from mobile phone map services. METHODS: We conducted a cross-sectional study using data from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR) including all ACS presentations during the pandemic until 7 May 2020. Using a count regression model, we adjusted for day of the week, daily weather and incidence of COVID-19. RESULTS: A 10% increase in activity around areas of residence was associated with 38% lower rates of ACS hospitalizations, whereas increased activity relating to retail and recreation, grocery stores and pharmacies, workplaces and mode of mobility was associated with 10-20% higher rates of ACS hospitalizations. CONCLUSION: Government policy regarding social containment mandates has important public health implications for medical emergencies such as ACS and may explain the decline in ACS presentations observed during COVID-19 pandemic.


Asunto(s)
Síndrome Coronario Agudo/epidemiología , COVID-19/epidemiología , Teléfono Celular , Ejercicio Físico , Pandemias , SARS-CoV-2 , Medio Social , Síndrome Coronario Agudo/prevención & control , Angioplastia Coronaria con Balón , COVID-19/prevención & control , Angiografía Coronaria , Estudios Transversales , Política de Salud , Humanos , Sistema de Registros , Análisis de Regresión , Factores de Riesgo , Políticas de Control Social , Suecia
8.
Int J Pharm ; 557: 254-263, 2019 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-30597263

RESUMEN

Extensive research has demonstrated the potential effectiveness of curcumin against various diseases, including asthma and cancers. However, few studies have used liquid-based vehicles in the preparation of curcumin formulations. Therefore, the current study proposed the use of nanoemulsion and microsuspension formulations to prepare nebulised curcuminoid for lung delivery. Furthermore, this work expressed a new approach to understanding the aerosol performance of nanoparticles compared to microsuspension formulations. The genotoxicity of the formulations was also assessed. Curcuminoid nanoemulsion formulations were prepared in three concentrations (100, 250 and 500 µg/ml) using limonene and oleic acid as oil phases, while microsuspension solutions were prepared by suspending curcuminoid particles in isotonic solution (saline solution) of 0.02% Tween 80. The average fine particle fraction (FPF) and mass median aerodynamic diameter (MMAD) of the nebulised microsuspension formulations ranged from 26% and 7.1 µm to 40% and 5.7 µm, for 1000 µg/ml and 100 µg/ml respectively. In a comparison of the low and high drug concentrations of the nebulised nanoemulsion, the average FPF and MMAD of the nebulised nanoemulsion formulations prepared with limonene oil ranged from 50% and 4.6 µm to 45% and 5.6 µm, respectively; whereas the FPF and MMAD of the nebulised nanoemulsion prepared with oleic acid oil ranged from 46% and 4.9 µm to 44% and 5.6 µm, respectively. The aerosol performance of the microsuspension formulations were concentration dependent, while the nanoemulsion formulations did not appear to be dependent on the curcuminoids concentration. The performance and genotoxicity results of the formulations suggest the suitability of these preparations for further inhalation studies in animals.


Asunto(s)
Curcumina/análogos & derivados , Curcumina/administración & dosificación , Sistemas de Liberación de Medicamentos , Nanopartículas/administración & dosificación , Administración por Inhalación , Aerosoles , Ensayo Cometa , Curcumina/química , Emulsiones , Pulmón/metabolismo , Nanopartículas/química , Nebulizadores y Vaporizadores , Concentración Osmolar , Tamaño de la Partícula , Viscosidad
9.
J Trop Pediatr ; 60(6): 480-1, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25096219

RESUMEN

Various studies conducted worldwide have shown that male neonates have higher rates of mortality and morbidity in the perinatal period compared with females. However, there has been only one study from India on this subject. Therefore, this study was conducted to establish the difference in mortality between males and females among neonates born with two established risk factors of septicaemia--low birth weight (<2.5 kg) and preterm birth (<37 weeks). One hundred and fifty consecutive neonates which were either preterm or had low birth weight were recruited after obtaining informed consent from the parents. Blood culture was done, and the bacterial isolates were identified by standard protocol. Statistically significant association was found between male gender and mortality among culture-positive neonates. Therefore, results of the present study indicate that preterm or low birth weight male neonates have higher likelihood of mortality compared with their female counterparts in the Indian scenario.


Asunto(s)
Mortalidad Infantil , Recién Nacido de Bajo Peso/sangre , Recien Nacido Prematuro/sangre , Sepsis/sangre , Factores Sexuales , Femenino , Humanos , India/epidemiología , Lactante , Recién Nacido , Masculino , Morbilidad , Embarazo , Estudios Prospectivos , Factores de Riesgo , Sepsis/microbiología , Sepsis/mortalidad
10.
Nano Lett ; 12(4): 1868-72, 2012 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-22432636

RESUMEN

Polysilicon nanowire biosensors have been fabricated using a top-down process and were used to determine the binding constant of two inflammatory biomarkers. A very low cost nanofabrication process was developed, based on simple and mature photolithography, thin film technology, and plasma etching, enabling an easy route to mass manufacture. Antibody-functionalized nanowire sensors were used to detect the proteins interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-α) over a wide range of concentrations, demonstrating excellent sensitivity and selectivity, exemplified by a detection sensitivity of 10 fM in the presence of a 100,000-fold excess of a nontarget protein. Nanowire titration curves gave antibody-antigen dissociation constants in good agreement with low-salt enzyme-linked immunosorbent assays (ELISAs). This fabrication process produces high-quality nanowires that are suitable for low-cost mass production, providing a realistic route to the realization of disposable nanoelectronic point-of-care (PoC) devices.


Asunto(s)
Técnicas Biosensibles/instrumentación , Membranas Artificiales , Nanocables/química , Polímeros/química , Silicio/química , Reacciones Antígeno-Anticuerpo , Biomarcadores/análisis , Cristalización , Ensayo de Inmunoadsorción Enzimática , Inflamación , Interleucina-8/análisis , Interleucina-8/inmunología , Polímeros/síntesis química , Propiedades de Superficie , Factor de Necrosis Tumoral alfa/análisis , Factor de Necrosis Tumoral alfa/inmunología
11.
Int J Anal Chem ; 2011: 604741, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22013443

RESUMEN

This study compares between unmodified carbon paste (CPE; the paste has no ion pair) and polyvinyl chloride (PVC) membrane selective electrodes that were used in potentiometric determination of ketotifen fumarate (KTF), where sodium tetraphenylborate (NaTPB) was used as titrant. The performance characteristics of these sensors were evaluated according to IUPAC recommendations which reveal a fast, stable, and linear response for KTF over the concentration range of 10(-7) to 10(-2) mol L(-1). The electrodes show Nernstian slope value of 52.51 ± 0.20 and 51.51 ± 0.25 mV decade(-1) for CPE and PVC membrane electrodes at 30°C, respectively. The potential is nearly stable over the pH range 3.0-6.0 and 2.0-7.0 for CPE and PVC membrane electrodes, respectively. Selectivity coefficient values towards different inorganic cations, sugars, and amino acids reflect high selectivity of the prepared electrodes. The electrodes responses at different temperatures were also studied, and long operational lifetime of 12 and 5 weeks for CPE and PVC membrane electrodes, respectively, were found. These are used for determination of ketotifen fumarate using potentiometric titration, calibration, and standard addition methods in pure samples, its pharmaceutical preparations (Zaditen tablets), and biological fluid (urine). The direct potentiometric determination of KTF using the proposed sensors gave recoveries % of 98.97 ± 0.53 and 98.62 ± 0.74 with RSD 1.42 and 0.63% for CPE and PVC membrane selective electrodes, respectively. Validation of the method shows suitability of the proposed sensors for use in quality control assessment of KTF. The obtained results were in a good agreement with those obtained using the reported spectrophotometric method.

12.
Biosci Trends ; 4(4): 186-9, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20811138

RESUMEN

The present study aims to determine the patterns of breast feeding, return of menstruation, and contraceptive practices in the first six months postpartum in women visiting the outpatient department at a teaching hospital in Lucknow, Northern India. Mothers of infants between six to eight months of age visiting the outpatient department of Era's Lucknow Medical College were interviewed regarding breast feeding practices, return of menstruation, sexual activity, and contraceptive practices within the first six months postpartum using a structured questionnaire. Of all women interviewed only 75.8% practiced exclusive breast feeding with the mean duration of exclusive breast feeding (EBF) being 3.5 months with only 41% practicing EBF for six months, 28% were sexually active within six weeks postpartum, 64.5% women had a return of menstruation within six months. Contraception was practiced by only 54.4% women with a barrier method such as a condom, being the most common. Better education was the only factor significantly affecting EBF (p < 0.004) and use of contraception (p < 0.027). There were a total of 10 pregnancies within six months postpartum. In conclusion, optimal breast feeding practices are poor in this part of the country and lactational amenorrhoea cannot be effectively and reliably used as a method of contraception. Therefore, optimal breast feeding practices, timely introduction of contraception and institutional delivery need to be encouraged.


Asunto(s)
Lactancia Materna , Conducta Anticonceptiva , Periodo Posparto , Adolescente , Adulto , Lactancia Materna/psicología , Lactancia Materna/estadística & datos numéricos , Conducta Anticonceptiva/psicología , Conducta Anticonceptiva/estadística & datos numéricos , Estudios Transversales , Femenino , Hospitales de Enseñanza , Humanos , India , Servicio Ambulatorio en Hospital , Periodo Posparto/psicología , Estudios Retrospectivos , Clase Social , Encuestas y Cuestionarios , Factores de Tiempo , Adulto Joven
13.
Wiad Parazytol ; 56(2): 153-61, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20707300

RESUMEN

Two trichodinid species were identified from freshwater fishes, Mystus bleekeri and Glossogobius giuris, in the Shitalakshya River of Gazipur district, Bangladesh. Trichodina acuta Lom, 1961 is found for the first time in Bangladesh. Trichodina shitalakshyae sp. n. is characterized by having an undivided clear central area in the adhesive disc with a rounded or slightly undulated perimeter containing a few dark granules which form patches; elongated and rectangular blade with large interblade space and blunt tangent point; indistinct anterior blade apophysis and a shallow apex at the base of blade that never extends beyond the Y+1 axis; moderately wide and triangular central part with blunt point; and space between tip of ray and central clear area forms a wide impregnated ring. Based on these characters and the unique shape and absence of variability of the denticles among the silver impregnated specimens of the present species, it resembles Trichodina porocephalusi Asmat, 2001.


Asunto(s)
Monitoreo del Ambiente , Peces/parasitología , Oligohimenóforos/aislamiento & purificación , Ríos/parasitología , Animales , Bangladesh , Branquias/parasitología , Oligohimenóforos/citología
14.
Int J Gynaecol Obstet ; 108(3): 199-202, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20015490

RESUMEN

OBJECTIVE: To evaluate the effect of transabdominal amnioinfusion on prolongation of pregnancy, and maternal and neonatal outcomes in preterm premature rupture of membranes (pPROM). METHODS: We conducted a prospective randomized controlled study of women with pPROM during singleton live pregnancy-between 26 and 33+6weeks-whose amniotic fluid index (AFI) was less than the 5th percentile. The study group underwent transabdominal amnioinfusion at admission and then weekly if their AFI fell below the 5th percentile again. The control group received expectant management. RESULTS: The difference in the mean interval from pPROM to delivery between the groups was not statistically significant. Neonatal and maternal outcomes were significantly improved in the study group compared with the control group (fetal distress [10% vs 37%]; early neonatal sepsis [17% vs 63%]; neonatal mortality [17% vs 63%]; spontaneous delivery [83% vs 53%]; and postpartum sepsis [7% vs 33%]). CONCLUSION: Transabdominal amnioinfusion reduced fetal distress, early neonatal sepsis, and neonatal mortality. In the study group, more participants delivered spontaneously and there were fewer cases of postpartum sepsis, although the pPROM-delivery interval was not increased.


Asunto(s)
Rotura Prematura de Membranas Fetales/terapia , Infusiones Parenterales , Nacimiento Prematuro/prevención & control , Cloruro de Sodio/administración & dosificación , Adulto , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Embarazo , Estudios Prospectivos , Resultado del Tratamiento , Adulto Joven
15.
Anal Quant Cytol Histol ; 27(2): 67-70, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15913198

RESUMEN

OBJECTIVE: To assess the utility of fine needle aspiration cytology (FNAC) and touch imprint cytology (TIC) in the evaluation of azoospermia. STUDY DESIGN: FNAC, TIC and open testicular biopsy (OTB) were used to evaluate 31 azoospermic men. RESULTS: OTB revealed normal spermatogenesis (10), spermatogenic arrest (12), Sertoli cell only syndrome (SCO) (7) and unsatisfactory cases (2). Cytologic examinations (TIC vs. FNAC) revealed normal spermatogenesis (11 vs. 9), spermatogenic arrest (13 vs. 7), SCO (2 vs. 1) and unsatisfactory cases (5 vs. 5). Sensitivity and specificity of TIC and FNAC were 98% vs. 83% and 100% vs. 93%, respectively. CONCLUSION: Testicular FNAC is a reliable and simple method for the evaluation of azoospermia.


Asunto(s)
Biopsia con Aguja Fina/métodos , Oligospermia/patología , Adulto , Biopsia con Aguja Fina/normas , Técnicas de Preparación Histocitológica , Humanos , Masculino
16.
Biochem J ; 260(2): 421-6, 1989 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-2764880

RESUMEN

Changes in the expression of heavy chains of myosin during development determine the functional characteristics of striated muscles. The distribution of heavy-chain isoforms of smooth-muscle myosin was determined in the airways of adult and infant humans to see whether it might underlie the hyperreactivity of human airways. The protein bands corresponding to myosin were separated using SDS/polyacrylamide-gel electrophoresis (4% gels) and identified by immunoblotting using both monoclonal and polyclonal antibodies against smooth-muscle myosin and non-muscle myosin. The relative proportion of each heavy chain stained by Coomassie Blue was measured by densitometric scanning. Three major bands corresponding to myosin heavy-chain isoforms were found; the two slower migrating bands (MHC1 and MHC2) were smooth-muscle myosin, and the third band was non-muscle myosin. The MHC1/MHC2 ratio was 0.69:1 in adult bronchus, and in infant bronchus and trachea. This contrasted with the airway smooth muscle in pigs, which was run concurrently, where the smooth-muscle heavy-chain ratio changed with development [Mohammad & Sparrow (1988) FEBS Lett. 228, 109-112]. The non-muscle myosin heavy chain comprised 63% of the smooth-muscle myosin. In both adult and infant lungs an additional putative myosin heavy chain which migrated slightly more rapidly than non-muscle myosin heavy chain was identified using the monoclonal smooth-muscle myosin antibody BF 48. This was unique to the human species.


Asunto(s)
Músculo Liso/análisis , Miosinas/análisis , Anciano , Bronquios/análisis , Femenino , Humanos , Lactante , Recién Nacido , Isomerismo , Masculino , Persona de Mediana Edad , Tráquea/análisis
17.
Jpn J Med Sci Biol ; 42(2): 51-61, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2561164

RESUMEN

The anti-leishmanial activity of ivermectin, pentostam or combination of pentostam with either levamisole or thymic extract was tested against Leishmania donovani infection in hamsters and mice. In vitro peritoneal macrophage-parasite interaction, the effect of splenic cells on the interaction of macrophages and parasites, spleen weight, parasite burden in spleen tissue as well as the antibody titers using micro-ELISA were used as parameters for evaluating the efficacy of these chemotherapeutic regimens. Treatment with ivermectin and immunoenhancement with pentostam combined with levamisole gave best results in both animal models. Furthermore, regimens used in this work were all active in reducing phagocytosis of promastigotes by macrophages in vitro.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Gluconato de Sodio Antimonio/uso terapéutico , Gluconatos/uso terapéutico , Ivermectina/uso terapéutico , Leishmaniasis/tratamiento farmacológico , Levamisol/uso terapéutico , Extractos del Timo/uso terapéutico , Animales , Cricetinae , Quimioterapia Combinada , Ensayo de Inmunoadsorción Enzimática , Técnicas In Vitro , Leishmania donovani/efectos de los fármacos , Leishmaniasis/inmunología , Macrófagos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , Tamaño de los Órganos/efectos de los fármacos , Bazo/anatomía & histología
18.
Pflugers Arch ; 412(6): 624-33, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3211713

RESUMEN

The myosin heavy chain stoichiometry and the force-velocity relation have been determined in the myometrium of the non-pregnant and pregnant rat. The relative proportions of the slower migrating heavy chain (MHC1) greatly exceeded that of the faster migrating heavy chain (MHC2) as shown by electrophoresis on SDS 4%-polyacrylamide gels. The ratios of MHC1/MHC2 were 2.2/1 in the non-pregnant rats, 2.6/1 in the pregnant rat, and contrasted with 0.8/1 in the rat portal vein. This stoichiometry was unchanged by extracting the myosin from the smooth muscle as native myosin in a salt extract, as dissociated myosin using sodium dodecyl sulphate (SDS) or by isolating the native myosin first by a non-dissociating (pyrophosphate) electrophoresis step and subsequently analysing the protein bands on the SDS 4%-polyacrylamide gel. Although the unequal proportions of the heavy chains suggested the possibility that the native myosin molecule may be arranged as homodimeric heavy chains, no evidence for or against the existence of native myosin isoforms could be obtained by electrophoresing native myosin extracts on pyrophosphate-polyacrylamide gels. The force-velocity relations of the intact electrically stimulated myometrium from the non-pregnant and pregnant rats gave isometric force of 45 and 135 mN/mm2 and Vmax of 0.71 and 0.52 lengths/s (37 degrees C) when measured at 95% of optimal length, whereas in chemically skinned uterine strips at 22 degrees C Vmax was 0.09 and 0.13 lengths/s, respectively. The length-force relationship was of similar shape in the non-gravid and gravid skinned tissues. The energetic tension cost (ATP-turnover/active stress) in skinned fibres was also similar. The mechanical and metabolic characteristics of the gravid and non-gravid uterus found in the present study do not suggest an obvious difference in the intrinsic properties of the myosin, although significant functional alterations in the tissue appear during pregnancy. This corresponds to the lack of a difference in the pattern of the heavy chains.


Asunto(s)
Músculo Liso/metabolismo , Miosinas/metabolismo , Útero/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Femenino , Miometrio/metabolismo , Embarazo , Ratas , Ratas Endogámicas , Contracción Uterina
19.
FEBS Lett ; 228(1): 109-12, 1988 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-3342866

RESUMEN

The stoichiometry of the myosin heavy chains (MHCs) has been measured in the tracheal smooth muscle of the pig after electrophoresis on SDS 4% polyacrylamide gel. The ratio of slower migrating MHC to the faster migrating MHC was 2.1 neonates, 1.5 in young and 0.95 in old pigs (P less than 0.01) showing that MHC composition changes with development. The unequal proportion of MHCs was not compatible with a heterodimeric arrangement of the MHCs in the native molecule as proposed earlier by Rovner et al. [(1986) Am. J. Physiol. 250, C861-870] and it is suggested that native molecules may be composed of homodimer heavy chains.


Asunto(s)
Músculo Liso/análisis , Miosinas/análisis , Fragmentos de Péptidos/análisis , Animales , Densitometría , Electroforesis en Gel de Poliacrilamida , Desarrollo de Músculos , Músculo Liso/crecimiento & desarrollo , Subfragmentos de Miosina , Porcinos , Tráquea/análisis , Tráquea/crecimiento & desarrollo
20.
Aust J Biol Sci ; 41(4): 409-19, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3152154

RESUMEN

The stoichiometry of the two heavy chains of myosin in smooth muscle was determined by electrophoresing extracts of native myosin and of dissociated myosin on sodium dodecyl sulfate (SDS) 4%-polyacrylamide gels. The slower migrating heavy chain was 3.6 times more abundant in toad stomach, 2.3 in rabbit myometrium, 2.0 in rat femoral artery, 1.3 in guinea pig ileum, 0.93 in pig trachea and 0.69 in human bronchus, than the more rapidly migrating chain. Both heavy chains were identified as smooth muscle myosin by immunoblotting using antibodies to smooth muscle and non-muscle myosin. The unequal proportion of heavy chains suggested the possibility of native isoforms of myosin comprised of heavy-chain homodimers. To test this, native myosin extracts wer electrophoresed on non-dissociating (pyrophosphate) gels. When each band was individually analysed on SDS-polyacrylamide gel the slowest was found to be filamin and the other bands were myosin in which the relative proportion of the heavy chains was unchanged from that found in the original tissue extracts. Since this is incompatible with either a heterodimeric or a homodimeric arrangement it suggests that pyrophosphate gel electrophoresis is incapable of separating putative isoforms of native myosin.


Asunto(s)
Músculo Liso/análisis , Miosinas/aislamiento & purificación , Animales , Bronquios/análisis , Bufo marinus , Electroforesis en Gel de Poliacrilamida , Femenino , Arteria Femoral/análisis , Cobayas , Humanos , Íleon/análisis , Sustancias Macromoleculares , Masculino , Miometrio/análisis , Conejos , Estómago/análisis , Porcinos , Tráquea/análisis
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