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1.
BMC Health Serv Res ; 22(1): 993, 2022 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-35927741

RESUMEN

BACKGROUND: Effective communication has been shown to increase patient satisfaction. The objective of this study was to describe communication strategies employed by physicians, and determine if physician communication strategies affect caregiver perception of quality or satisfaction with physician communication in a pediatric ambulatory setting. METHODS: This observational study was conducted at the Children's Hospital of Philadelphia and consisted of video recordings of visits that were reviewed by research assistants for physician utilized communication strategies. Caregivers completed surveys on their preferred physician communication qualities, perception of communication quality, and satisfaction with communication. Correlation was performed between types of communication strategy and caregiver satisfaction with communication or perceived quality of communication. T-tests were run to see if there was a significant difference in patient perceived communication and satisfaction scores based on the communication strategies utilized during visits. RESULTS: There were five universally used communication strategies across the 84 clinic visits recorded, including: eye contact, good posture, speaking concisely, providing thorough explanations, and providing summary of next steps. The average number of communication strategies used was 15.95 (σ = 1.50) with physicians using at least 16 of the 18 communication strategies in 62% of the clinic visits. There was no correlation between the number of communication strategies physicians utilized and either the caregiver perception of communication quality score (CPCQ) or communication satisfaction (CS) score. Caregivers who preferred an authoritative approach but perceived a collaborative approach reported lower average CPCQ and CS scores compared to caregivers who had their communication expectations met. DISCUSSION: There are numerous tools designed to help the physician facilitate an effective working relationship with the patient. In our study, the universally used verbal communication strategies are generally recognized as components of an effective communication repertoire. Another part of effective communication is meeting communication expectations with the CS scores suggesting that caregivers felt their communication needs were being met. Dedicating clinical time to understanding this need may help improve the overall clinical experience. CONCLUSION: Physicians utilize many of the suggested communication strategies to help facilitate an effective clinical encounter. Further studies on caregiver communication requirements and meeting caregiver communication expectations are needed.


Asunto(s)
Comunicación , Pacientes Ambulatorios , Médicos , Cuidadores , Niño , Humanos , Satisfacción del Paciente , Relaciones Médico-Paciente , Encuestas y Cuestionarios
2.
J Anim Breed Genet ; 131(2): 116-22, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24628723

RESUMEN

Higher average daily gain, more lean meat yield and less fat yield of porcine carcass increase selling profits for animal producers. Myostatin (MSTN), previously called GDF8, is a member of transforming growth factor-ß (TGF-ß) superfamily. It is a negative regulator for both embryonic development and adult homeostasis of skeletal muscle. In this study, the genotypes of the previously described SNPs MSTN g.435G>A and g.447A>G SNPs in 66 Duroc pigs, 33 Landrace pigs, 180 Duroc × Landrace (DL) pigs and 155 Duroc × Yorkshire × Landrace (DYL) pigs were determined by Taqman SNP Genotyping Assays. For Duroc and Landrace pigs, MSTN g.435GG/g.447AA individual had greater backfat thickness (p < 0.05) than g.435AA/g.447GG individual, whereas MSTN g.435AA/g.447GG had greater meat (p < 0.05) and meat percentage (p < 0.05) than g.435GA/g.447AG individual. For DL and DYL pigs, the MSTN g.435GG/g.447AA animals were greater in backfat at ultrasound 10th rib (p < 0.05) and carcass 10th rib (p < 0.01) than g.435AA/g.447GG individual. The MSTN g.435AA/g.447GG individual also had higher values than g.435GG/g.447AA for anterior-end meat (p < 0.05), posterior-end meat (p < 0.01), total meat weight (p < 0.01) and meat percentage (p < 0.01). This study confirmed evidence that MSTN g.435G>A and g.447A>G affected carcass traits in pigs. The effects of the mutated alleles were additive with the maximal effects resulting from two copies of the mutated allele. Selection for MSTN g.435A/g.447G allele is expected to increase muscle of limb and total meat production and decrease backfat thickness.


Asunto(s)
Miostatina/genética , Fenotipo , Regiones Promotoras Genéticas/genética , Porcinos/anatomía & histología , Porcinos/genética , Animales , Técnicas de Genotipaje , Polimorfismo de Nucleótido Simple , Especificidad de la Especie
3.
Anim Biotechnol ; 23(4): 278-90, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23134307

RESUMEN

The aim of this study was to investigate the genetic relationships between Taiwan black pigs (TBP) and other pig breeds by means of 15 fluorescent-labeled microsatellite markers. DNA from a total of 299 TBP from eight private farms and 234 purebred pigs representing six breeds and one synthetic line was used. Among the 15 microsatellite loci, polymorphism information content (PIC) values were all above 0.500; the numbers of observed alleles were all greater than the numbers of effective alleles (10.1 vs. 4.3 in averages). But 13 of the 15 microsatellite markers significantly deviated from the Hardy-Weinberg equilibrium (HWE); moreover, 13 of the 15 tested populations also deviated from the HWE. The inbreeding coefficient (F(IS)) indicated that two TBP populations (TBP-3 and TBP-4) had heterozygote deficiency (P < 0.01). The pair-wise F(ST), representing the genetic diversity between the two populations, ranged from 0.0332 to 0.3809. Meishan and Taoyuan breeds with black hair were previously considered closely related to TBP; however, the result of genetic relationship refuted this assumption. In conclusion, TBP is more similar to the European than Chinese breeds, and further investigations will need to clarify it more accurately.


Asunto(s)
Repeticiones de Microsatélite , Sus scrofa/genética , Animales , Análisis por Conglomerados , Variación Genética , Filogenia , Sus scrofa/clasificación , Taiwán
4.
Reprod Domest Anim ; 47(1): 69-81, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21599764

RESUMEN

The survival and development of pre-implantation embryos are determinant factors affecting the outcome of animal reproduction. It is essential to transfer the expression of the genetic material from maternal sources, that is the ovum to the zygote before implantation to ensure successful development. Differentiation and transformation of blastomeres initiated during the morula and blastocyst stages is an important step of the embryonic development prior to implantation. We collected morula and early blastocyst samples from pure-bred Landrace pigs in vivo to study the differential gene expression patterns at these two stages. Total RNA was extracted from individual embryos and two rounds of amplification were employed. Two micrograms of antisense RNA, targets, were prepared and hybridized with each of four custom made oligo microarrays representing 24,000 porcine genes. The analyses of replicate hybridizations showed that among the 24,000 genes, 162 genes were expressed fivefold or greater in the morula compared to early blastocysts and 2126 genes were expressed fivefold or greater in early blastocysts compared to the morula. Of these differentially expressed genes, 1429 genes were functionally annotated with related human Gene Ontology terms. In addition to basic metabolic processes, genes related to signal transduction, transportation and cell differentiation were found in both stages and were up-regulated as embryo development proceeded. Real time polymerase chain reaction was utilized to quantify 12 genes differentially expressed in the 2 embryonic stages and validated the reliability of major evidences shown in microarrays. In conclusion, we have obtained a preliminary landscape of genes differentially expressed during the transition from morula to early blastocysts in pigs and showed a generally increased transcriptional activity, perhaps in preparation for implantation. Our results provide an opportunity to study the functions of these genes in relation to the development and survival of pre-implantation porcine embryos.


Asunto(s)
Blastocisto/metabolismo , Perfilación de la Expresión Génica/veterinaria , Expresión Génica , Mórula/metabolismo , Sus scrofa/embriología , Animales , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena en Tiempo Real de la Polimerasa , Sus scrofa/genética
5.
Science ; 153(3737): 755-7, 1966 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-5328677

RESUMEN

Fructose-1 ,6-diphosphate is a feedback inhibitor of the catabolic enzyme, glycerol kinase, in Escherichia coli. A mutant was isolated which produced a desensitized enzyme. Glucose was no longer as effective in preventing the utilization of exogenous glycerol by cells which synthesized constitutively such an altered enzyme, even though the usual degree of catabolite repression still operated.


Asunto(s)
Enzimas , Escherichia coli/enzimología , Retroalimentación , Glucosa/metabolismo , Glicerol/metabolismo , Fosfatos/farmacología , Fosfotransferasas/metabolismo , Técnicas In Vitro
6.
Science ; 292(5525): 2314-6, 2001 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-11423658

RESUMEN

The Arc two-component signal transduction system mediates adaptive responses of Escherichia coli to changing respiratory conditions of growth. Under anaerobic conditions, the ArcB sensor kinase autophosphorylates and then transphosphorylates ArcA, a global transcriptional regulator that controls the expression of numerous operons involved in respiratory or fermentative metabolism. We show that oxidized forms of quinone electron carriers act as direct negative signals that inhibit autophosphorylation of ArcB during aerobiosis. Thus, the Arc signal transduction system provides a link between the electron transport chain and gene expression.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas de Escherichia coli , Escherichia coli/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Quinasas/metabolismo , Quinonas/metabolismo , Proteínas Represoras , Transducción de Señal , Vitamina K 2/análogos & derivados , Vitamina K/análogos & derivados , Aerobiosis , Transporte de Electrón , Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica , Mutación , Oxidación-Reducción , Fosforilación , Ubiquinona/metabolismo , Vitamina K/metabolismo
7.
Poult Sci ; 88(9): 1955-62, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19687282

RESUMEN

Geese have a short egg-laying period and a low egg production rate. To induce and maintain egg laying, genes related to generating hepatic lipid for yolk deposition should be adequately expressed. Liver mRNA from 6 laying geese was extracted and used for construction of a full-length enriched cDNA library. About 2,400 clones containing gene sequences were determined and National Center for Biotechnology Information Gallus gallus Gene Index databases were used to compare and analyze these sequences. Ten highly expressed genes were selected to determine the differential expression between laying and prelay goose liver. Tissue distribution data showed that very low density apolipoprotein II, liver type fatty acid binding protein, vitellogenin I, and vitellogenin II transcripts were specifically expressed in the liver of laying geese. Ovoinhibitor, preproalbumin, alpha-2-hs-glycoprotein, and vitamin D binding protein mRNA were highly expressed in the liver and to a lesser extent in other tissues. Ovotransferrin mRNA was expressed in liver, ovary, oviduct, shell gland, brain, and adipose tissues. The concentration of transthyretin mRNA was high in the liver and brain. The mRNA concentrations of liver type fatty acid binding protein, alpha-2-hs-glycoprotein, and transthyretin in the livers of laying and prelay geese were not different. The concentrations of hepatic ovotransferrin, ovoinhibitor, preproalbumin, very low density apolipoprotein II, vitellogenin I, vitellogenin II, and vitamin D binding protein mRNA were higher in the liver of laying geese than in prelay geese, suggesting that these genes may be involved in laying function or lipid metabolism related to egg formation.


Asunto(s)
Gansos/genética , Gansos/metabolismo , Hígado/metabolismo , Oviposición/fisiología , Animales , Femenino , Perfilación de la Expresión Génica , Biblioteca de Genes , Maduración Sexual , Distribución Tisular
8.
Neurogastroenterol Motil ; 27(2): 277-84, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25545126

RESUMEN

BACKGROUND: Manoscan(™) is one of the commonly used high-resolution manometry (HRM) systems with declared measurement accuracy of 1-2 mmHg. However, the accuracy of pressure measurements is limited by development of pressure drift (PD) throughout recording. To date, there has been no systematic investigation to identify the factors contributing to PD. The aim of the present study was to characterize the frequency and magnitude of PD in Manoscan(™) system and identify the factors contributing to PD. METHODS: Records of 560 consecutive clinical esophageal HRM studies recorded by six distinct HRM catheters were retrospectively reviewed. PD was defined as the residual pressure measurement by each sensor immediately after removal of the catheter. Non-parametric locally weighted regression analysis was performed to assess the effect of duration of study, number of prior uses of a catheter, peak and average pressure exposure during a study on the PD. KEY RESULTS: The majority (95%) of clinical manometry studies showed a non-negligible PD of more than 5 mmHg. The overall PD was 13 ± 5 mmHg and the sensor with greatest amount of PD showed 23 ± 12 mmHg of drift. The upper esophageal sphincter showed the highest PD. Average pressure exposure of a sensor throughout the recording was the most important predictor of PD. PD inversely correlated with number of prior uses of a catheter. CONCLUSIONS & INFERENCES: The PD preferentially affects esophageal high-pressure zones, and strongly correlates with 'average pressure exposure' of a sensor during manometry. Available algorithms of the analysis software do not adequately correct the PD.


Asunto(s)
Trastornos de la Motilidad Esofágica/diagnóstico , Interpretación de Imagen Asistida por Computador/métodos , Manometría/instrumentación , Manometría/métodos , Algoritmos , Catéteres , Esfínter Esofágico Superior/fisiopatología , Humanos , Presión , Estudios Retrospectivos
9.
Gene ; 136(1-2): 227-30, 1993 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-8294007

RESUMEN

The cpxA gene of Escherichia coli K-12 encodes a membrane-associated sensor element of a two-component signal transduction system in bacteria. The cognate regulator element, however, has not yet been definitively identified. A 2.1-kb segment upstream from cpxA was amplified by polymerase chain reaction, cloned and sequenced. An open reading frame encoding 232 amino acids was found. It showed high homology to the regulator elements of two-component transduction systems. The newly identified gene, designated as cpxR, may encode the cognate protein receiving signals from CpxA.


Asunto(s)
Proteínas Bacterianas/genética , Escherichia coli/genética , Transducción de Señal , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN Bacteriano , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido
10.
Clin Exp Metastasis ; 16(1): 50-61, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9502077

RESUMEN

Integrins with the alphav subunit are involved in cell adhesion and cellular signaling. Some alphav integrins have been associated with tumor progression and dissemination. The objective of this study was to assess the contribution of alphav integrins to the adhesive and migratory behavior of cells derived from breast carcinoma (BCA). The expression and function of alphav integrins was characterized in three BCA cell lines which exhibit different metastatic potentials. These include MCF-7 cells which metastasize inefficiently, MDA-MB-231 cells, which have a moderate metastatic potential, and MDA-MB-435 cells, which metastasize extensively. Each cell type displays a different repertoire of alphav integrins on the cell surface. The complement of alphav integrins on each cell type influences their ability to adhere and migrate. The most striking difference among these cell lines was the expression of the alphavbeta3 integrin. The highly metastatic MDA-MB-435 cells express substantial levels of this receptor, whereas MDA-MB-231 and MCF-7 cells do not. The MDA-MB-435 cells showed a greater ability to adhere and to migrate and this functional difference can largely be attributed to the expression of alphavbeta3 integrin. This characterization is a first step toward determining the role of alphav integrins in animal models of BCA metastasis, and lends support to the hypothesis that the alphavbeta3 integrin can be a contributing factor in metastatic disease.


Asunto(s)
Antígenos CD/fisiología , Neoplasias de la Mama/patología , Adhesión Celular , Movimiento Celular , Integrinas/fisiología , Proteínas de Neoplasias/fisiología , Antígenos CD/aislamiento & purificación , Neoplasias de la Mama/enzimología , Carcinoma/enzimología , Carcinoma/patología , Femenino , Citometría de Flujo , Humanos , Integrina alfaV , Integrinas/aislamiento & purificación , Pruebas de Precipitina , Células Tumorales Cultivadas , Vitronectina/fisiología
11.
Atherosclerosis ; 112(2): 161-75, 1995 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-7772076

RESUMEN

To study dietary fat and cholesterol effects on plasma high density lipoprotein (HDL) metabolism and rates of apolipoprotein (apo) A-I catabolism, guinea pigs were fed 15% (wt/wt) lard- or corn oil-based diets with 0.01% (basal), 0.08%, 0.17% or 0.33% cholesterol. Absorbed dietary cholesterol provided 6%, 50%, 100% and 200%, respectively, of the daily endogenous cholesterol synthetic mass. While total plasma cholesterol concentrations increased significantly above basal levels at the 0.17% and 0.33% cholesterol intakes, plasma apo E-free HDL (EoHDL) cholesterol concentrations did not increase significantly until the 0.33% cholesterol level (P < 0.001). Fractional catabolic rates (FCR) of injected [131I]-apo A-I were not altered by dietary treatment, either fat saturation or cholesterol, but were inversely correlated with plasma EoHDL cholesterol levels (r = -0.622), suggestive of a regulatory role of turnover rates on HDL cholesterol levels independent of dietary treatment. Analysis of the high affinity EoHDL binding to isolated hepatic membranes suggested that hepatic binding was not a determinant of HDL catabolism, as dietary cholesterol-induced decreases in Bmax (binding capacity) were not correlated with changes in apo A-I FCR. Even though dietary cholesterol was associated with increased plasma EoHDL cholesterol and with decreased HDL binding protein Bmax, these values did not correlate with each other nor with effects on apo A-I FCR.


Asunto(s)
Colesterol en la Dieta/farmacología , HDL-Colesterol/sangre , Grasas de la Dieta/farmacología , Animales , Apolipoproteína A-I/sangre , Apolipoproteína A-I/metabolismo , HDL-Colesterol/metabolismo , Cobayas , Hígado/metabolismo , Masculino , Unión Proteica , Ensayo de Unión Radioligante
12.
Endocrinol Metab Clin North Am ; 30(2): 469-92, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11444171

RESUMEN

Many isotopes are available for imaging patients with suspected thyroid cancer recurrence and metastases. TSH-stimulated low-dose 131I whole-body scanning with serum thyroglobulin either by standard LT4 withdrawal or rhTSH stimulation is the preferred test for monitoring patients without palpable disease or elevated serum thyroglobulin on LT4 therapy (Fig. 5). This approach has the advantage of finding disease that may be amenable to 131I therapy, although low-dose 131I scans are less sensitive than are scans with other imaging agents. 123I has better imaging characteristics than 131I and has been shown to be equivalent or superior to low-dose 131I in recent studies. As the availability of 123I increases and the cost decreases, this agent may replace 131I in imaging for recurrent or metastatic thyroid cancer. Patients who have an elevated serum thyroglobulin on LT4 therapy or after TSH stimulation but have a negative low-dose 131I scan require other imaging procedures to find the suspected disease. The authors currently perform a sensitive neck ultrasound to look for surgically remediable disease and consider a noncontrast CT scan of the chest to look for small pulmonary metastases that poorly concentrate low doses of 131I (Fig. 5). Fluoro-18-deoxyglucose PET, 99mTc MIBI, 201Tl, and 99mTc tetrofosmin are primarily useful in the setting of a negative whole-body 131I scan and elevated serum thyroglobulin. 18FDG-PET seems to have the highest sensitivity in this setting and would be the preferred imaging agent, but availability and cost are major issues (Fig. 5). Although some researchers have advocated these radiopharmaceuticals as first-line agents replacing 131I, there is little support for this position. This approach to imaging is not cost-effective because positive scans in these patients would most likely require 131I scintigraphy to determine whether the lesions are amenable to radioiodine therapy. 99mTc pertechnetate, 99mTc furifosmin, and somatostatin receptor scintigraphy have a limited role in imaging for recurrent or metastatic differentiated thyroid carcinoma. In choosing among 99mTc MIBI, 201Tl, and 99mTc tetrofosmin, the technetium label of sestamibi and tetrofosmin results in better image quality and faster imaging than 201Tl. Although 99mTc sestamibi and 99mTc tetrofosmin have not been compared in a large series, the higher tumor-to-background ratio and consistently high sensitivities of 99mTc tetrofosmin suggest that it could potentially have additional value over 99mTc sestamibi, but there is still limited experience with 99mTc tetrofosmin.


Asunto(s)
Radioisótopos de Yodo , Metástasis de la Neoplasia/diagnóstico por imagen , Neoplasias de la Tiroides/diagnóstico por imagen , Humanos , Radioisótopos de Yodo/administración & dosificación , Compuestos de Organotecnecio , Cintigrafía , Radiofármacos , Talio , Radioisótopos de Talio , Tirotropina
13.
J Nutr Biochem ; 10(3): 172-80, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15539286

RESUMEN

We measured the interactive effects of dietary cholesterol and fat on the regulation of hepatic acyl-CoA:cholesterol acyltransferase (ACAT) activity and its relationship to hepatic microsomal lipid composition in guinea pigs fed 15 g/100 g (w/w) fat diets (corn oil, olive oil, or lard) with 0.01, 0.08, 0.17, or 0.33 g/100 g (w/w) added cholesterol. Guinea pigs exhibited a dose dependent increase in hepatic microsomal ACAT activity, with increasing levels of cholesterol intake (P < 0.001) in all dietary fat groups. Animals fed monounsaturated olive oil had the highest hepatic ACAT activity with the exception of the 0.33 g/100 g cholesterol diet (P < 0.001). There were no differences in ACAT activity with intake of polyunsaturated corn oil or saturated lard. Dietary cholesterol resulted in increased microsomal free cholesterol (FC) concentrations in a dose dependent manner but had no effects on microsomal phosphatidylcholine (PC) concentrations. Guinea pigs fed olive oil generally had the highest microsomal FC/PC molar ratios, and hepatic ACAT activities correlated significantly with this parameter. After modification of the lipid compositions of the microsomes from guinea pigs fed the 12 test diets with FC/PC liposome treatment, microsomal ACAT activities remained significantly related to the microsomal FC/PC molar ratios, and dietary fat type did not affect this correlation. Our findings do not support the hypothesis that the stimulation of hepatic ACAT activity with cholesterol intake is enhanced by polyunsaturated fat intake. The data demonstrate that although dietary fat type and cholesterol amount have differential effects on hepatic ACAT activity, substrate availability, expressed as microsomal FC/PC molar ratio, is a major regulator of hepatic microsomal ACAT activity.

14.
J Chromatogr A ; 879(2): 197-210, 2000 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-10893036

RESUMEN

The influences of buffer pH, buffer concentration and buffer electrolyte on the migration behavior and separation of 12 cephalosporin antibiotics in capillary zone electrophoresis using three different types of buffer electrolyte, including phosphate, citrate, and 2-(N-morpholino)ethanesulfonate (MES), were investigated. The results indicate that, although buffer pH is a crucial parameter, buffer concentration also plays an important role in the separation of cephalosporins, particularly when cefuroxime and cefazolin, cephalexin and cefaclor, or cefotaxime and cephapirin are present as analytes at the same time. The electrophoretic mobility of cephalosporins and electroosmotic mobility measured in citrate and MES buffers are remarkably different from those measured in phosphate buffer. With citrate buffer, optimum buffer concentration is confined to a small range (35-40 mM), whereas buffer concentrations up to 300 mM can be used with MES buffer. Complete separations of 12 cephalosporins could be satisfactorily achieved with these three buffers under various optimum conditions. However, the separability of 12 cephalosporins with citrate or MES buffer is better than that with phosphate buffer. As a consequence of a greater electrophoretic mobility of cephalosporins than the electroosmotic mobility with citrate buffer at pH below about 5, some cephalosporins are not detectable. The cloudiness of the peak identification and of the magnitudes of the electrophoretic mobility of cefotaxime and cefuroxime reported previously are clarified. In addition, the pKa values of cephradine, cephalexin, cefaclor, and cephapirin attributed to the deprotonation of either an amino group or a pyridinium group are reported, and the migration behavior of these cephalosporins in the pH range studied is quantitatively described.


Asunto(s)
Cefalosporinas/aislamiento & purificación , Electroforesis Capilar/métodos , Ácidos Alcanesulfónicos/química , Tampones (Química) , Cefalosporinas/química , Electrólitos , Concentración de Iones de Hidrógeno , Morfolinas/química
15.
J Chromatogr A ; 755(2): 261-9, 1996 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-8997751

RESUMEN

The influence of buffer pH and electrolyte modifier on the migration behavior and separation of thirteen sulfonamides was investigated by capillary zone electrophoresis. The results indicate that precise optimization of buffer pH is crucial in improving the separation of some closely migrating sulfonamides. On the addition of either an appropriate amount of an organic modifier (methanol or acetonitrile) or a low concentration of beta-cyclodextrin (beta-CD, 0.5 mM) to a phosphate-borate buffer at pH 6.85 and an applied voltage of 20 kV, the resolution of peaks between sulfathiazole and sulfamethoxypyridarine is markedly enhanced and effective separations of thirteen sulfonamides are achieved within a relatively short time. Methanol gives better resolution than acetonitrile as an organic modifier. Weak inclusion complexation occurs between beta-CD and sulfonamides, with the exception of sulfathiazole. The formation constants of thirteen sulfonamides with beta-CD are reported.


Asunto(s)
Electroforesis Capilar/métodos , Sulfonamidas/aislamiento & purificación , beta-Ciclodextrinas , Animales , Tampones (Química) , Ciclodextrinas/química , Electrólitos , Concentración de Iones de Hidrógeno , Leche/química , Sulfonamidas/química
16.
Comp Med ; 51(6): 545-9, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11924818

RESUMEN

PURPOSE: Echocardiography played an important role in the screening and diagnosis of hypertrophic cardiomyopathy. In the study reported here, we attempted to evaluate the effects of birth season, breed, sex, and sire family on cardiac morphology determined in pigs by use of echocardiography. METHODS: A total of 411 pigs (mean body weight and age of 105.7 +/- 10.6 kg and 214.4 +/- 25.5 days, respectively) with different genetic backgrounds (Landrace, Yorkshire, and their two-way crossbred) were studied. Cardiac morphologic measurements included thickness of left ventricle and interventricular septum at end-systolic and end-diastolic phases. Meanwhile, the statistical model included the following effects: birth season, breed, sex, interaction between breed and sex, sire family, body weight, and age. RESULTS: Mean cardiac morphologic measurements were as follows: thickness of the interventricular septum at end-systolic and end-diastolic phases was 1.74 and 1.14 cm, respectively; and thickness of the left ventricular free wall at end-systolic and end-diastolic phases was 1.81 and 0.98 cm, respectively. Medium positive correlations existed among the cardiac morphologic measurements r = 0.31 to 0.53; P < 0.001). Pigs born in spring had significantly (P < 0.05) lower cardiac thickness at the end systolic phase than did pigs born in other seasons, and Landrace pigs had higher cardiac morphologic measurements than did Yorkshire and two-way crossbred pigs. Additionally, thickness of interventricular septum at the end-diastolic phase in male pigs was significantly higher than that in female pigs (P < 0.05). Cardiac morphologic measurements for the sire family were significantly (P < 0.05) different, and contributed 77.2 to 87.9% of the total variation, suggesting that genetic variation in cardiac morphology might exist in pigs. CONCLUSIONS: Cardiac morphology of pigs might be influenced by genetic background. The effects of birth season, breed, sire family, and sex should be adjusted when using pigs as an animal model for comparative cardiovascular studies.


Asunto(s)
Corazón/anatomía & histología , Porcinos/anatomía & histología , Animales , Cruzamiento , Ecocardiografía , Femenino , Masculino , Estaciones del Año , Caracteres Sexuales , Especificidad de la Especie
17.
Anim Reprod Sci ; 63(3-4): 231-40, 2000 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-10989233

RESUMEN

This study attempted to clarify the relationship between the levels of 70kDa heat shock protein (HSP70) and semen quality in boars. Semen samples from 29 (13 Duroc, 9 Landrace, and 7 Yorkshire) boars (mean age=25.2+/-2.2 months) were examined. Three to four ejaculates per boar, collected during cool and hot seasons, were evaluated in terms of the sperm concentration, sperm motility, percentage of normal and abnormal sperm, as well as percentage of sperm with proximal and distal plasma droplets. Significant seasonal and breed differences in semen quality were observed. Experimental results indicate that the semen quality of Landrace boars was better than those of Yorkshire and Duroc boars (P<0.05) and semen quality declined significantly during the hot season (P<0.05). One-dimensional SDS-PAGE analysis of spermatozoa proteins indicated that protein profiles did not significantly differ between seasons and among breeds. Both constitutive and stress-inducible form of HSP70 were detected in boar spermatozoa by Western blot analysis. The level of HSP70, which revealed no difference among breeds within a season, was significantly lower during the hot season in all the three breeds (P<0.05). Although there appeared to be low correlation coefficients between the level of HSP70 and semen quality traits, the semen quality tended to decline significantly in samples with a lower level of HSP70. Results in this study suggest that the levels of HSP70 in boar spermatozoa are significantly lower during the hot season and might be associated with semen quality.


Asunto(s)
Proteínas HSP70 de Choque Térmico/análisis , Semen/química , Porcinos/fisiología , Animales , Western Blotting/veterinaria , Masculino , Proteínas/análisis , Estaciones del Año , Especificidad de la Especie , Porcinos/clasificación
18.
Anim Reprod Sci ; 70(1-2): 99-109, 2002 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-11841910

RESUMEN

This study aims to elucidate the effects of single nucleotide polymorphisms (SNPs) in the 5'-flanking region of porcine heat shock protein 70.2 gene (HSP70.2) on semen quality in boars. Genomic DNA isolated from 55 boars (41 Duroc, nine Landrace, and five Yorkshire) was subjected to PCR amplification of the 5'-flanking region of HSP70.2. The nucleotide sequences were determined by automated sequencing. Five SNPs (sites 44, 232, 250, 345, and 393) were detected in this region. Semen quality was evaluated in terms of sperm motility, percentage of normal sperm, percentage of sperm with proximal plasma droplet, percentage of abnormal sperm, sperm concentration, semen volume per ejaculate and total sperm number per ejaculate. The effect of the SNPs on semen quality was evaluated based on breed-corrected data within a season. During the cool season, the sperm motility of boars with AA genotype at the 232 site was significantly higher than that of boars with CC genotype (P<0.05). Meanwhile, boars with AC genotype at the 232 site had higher total sperm number per ejaculate than did those with CC genotype. In the hot season, heterozygotes at both the 232 and 250 sites had significantly higher total sperm number of per ejaculate than AA homozygotes (P<0.05). Semen volume of boars with TT and TC genotypes at the 345 site was significantly larger than that of those with CC genotype (P<0.05). Meanwhile, semen quality for boars with TT genotype at the 345 site was significantly higher than that of boars with TC or CC genotype (P<0.05), that is the semen contained higher percentages of normal sperm and lower percentages of abnormal sperm or sperm with proximal plasma droplets. Results herein suggest that the SNPs in the 5'-flanking region of porcine HSP70.2 are associated with semen quality traits in the hot season.


Asunto(s)
Proteínas HSP70 de Choque Térmico/genética , Polimorfismo de Nucleótido Simple , Semen/fisiología , Porcinos/genética , Porcinos/fisiología , Animales , Secuencia de Bases , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Estaciones del Año , Análisis de Secuencia de ADN , Recuento de Espermatozoides , Motilidad Espermática , Espermatozoides/anomalías
19.
J Anim Sci ; 75(12): 3114-8, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9419983

RESUMEN

Differences between porcine stress syndrome (PSS) normal (NN) and carrier (Nn) Landrace dams were determined for adjusted number of pigs born alive, adjusted number of pigs at 21 d, adjusted 21-d litter weight, proportion of pigs surviving to 21 d, and farrowing interval. Data were analyzed from a total of 841 females, 623 normal (NN) and 218 carriers (Nn) having 2,231 and 869 records, respectively. Three susceptible (nn) females from two herds were dropped from the analysis because of their small contribution to the total number of records. Frequency of the recessive PSS allele ranged from .07 to .28 in the nine herds involved in this study. Data were adjusted using Landrace breed-specific adjustments and analyzed with mixed-model derivative-free REML procedures fitting the dams' PSS genotype as a fixed effect in the model. Only females having two or more successive parities were used in the analysis of farrowing interval, resulting in a reduction of total records analyzed to 2,201 (1,564 NN and 637 Nn records) from 632 females (445 NN and 187 Nn females). No differences between NN and Nn dams were observed for adjusted number of pigs born alive, adjusted number of pigs at 21 d, adjusted 21-d litter weight, proportion of pigs surviving to 21 d, and farrowing interval. The results of this investigation indicate no significant maternal performance differences between PSS NN or Nn Landrace dams.


Asunto(s)
Reproducción/genética , Estrés Fisiológico/veterinaria , Enfermedades de los Porcinos/genética , Porcinos/genética , Alelos , Animales , Cruzamiento , Femenino , Frecuencia de los Genes , Heterocigoto , Fenotipo , Reproducción/fisiología , Estrés Fisiológico/genética , Estrés Fisiológico/fisiopatología , Porcinos/crecimiento & desarrollo , Porcinos/fisiología , Enfermedades de los Porcinos/fisiopatología , Síndrome
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