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1.
Georgian Med News ; (348): 36-39, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38807387

RESUMEN

Preterm birth (PTB) is defined as birth before 37 completed weeks of gestation. It is generally agreed, preterm delivery is the most important obstetrical complication leading to perinatal morbidity and mortality. The aim of this study is to assess the prevalence of progesterone prescription, the route of administration, the prevalence of PTB, and the route of delivery as well as to look at the rates of PTB among those who received progesterone and those who did not. An observational cross-sectional study among postpartum women was done between April and September 2023. A convenience sample of 300 women were interviewed at maternity hospitals and primary health centers in Duhok. A survey of postpartum women up to 1 year postpartum was completed. Patients were questioned about basic pregnancy information, risk factors, and complications, as well as the use (if any) of progesterone. The preterm birth (<37 week) rate is 12%. From the 300 patients in the sample, 114 (38%) women had history of single or multiple progesterone therapies. The most common single route of progesterone therapy was the parenteral route (29.8%), but more patients received progesterone via multiple routes (32.4%). Pre-term birth was reported in 19 women who received progesterone treatment compared to 17 women among those who did not receive progesterone treatment. No statistically significant variations were found between the two groups (P=0.08). There were no statistically significant differences in prevalence of PTB or route of delivery between women who received progesterone supplementation and those who did not receive progesterone (P=0.08 and P= 0.14 respectively). Prior research has shown that the clearest evidence of benefit for progesterone in pregnancy is among those with short cervix. Perhaps the lack of significant difference found in this study was because of prescriptions outside of established indications. More randomized controlled trials are needed to assess the effects of progesterone supplementation during pregnancy.


Asunto(s)
Nacimiento Prematuro , Progesterona , Humanos , Femenino , Embarazo , Progesterona/administración & dosificación , Progesterona/uso terapéutico , Nacimiento Prematuro/epidemiología , Estudios Transversales , Adulto , Prevalencia , Adulto Joven , Progestinas/administración & dosificación , Progestinas/uso terapéutico , Factores de Riesgo
2.
Ultrasound Obstet Gynecol ; 48(3): 318-32, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27349699

RESUMEN

The IDEA (International Deep Endometriosis Analysis group) statement is a consensus opinion on terms, definitions and measurements that may be used to describe the sonographic features of the different phenotypes of endometriosis. Currently, it is difficult to compare results between published studies because authors use different terms when describing the same structures and anatomical locations. We hope that the terms and definitions suggested herein will be adopted in centers around the world. This would result in consistent use of nomenclature when describing the ultrasound location and extent of endometriosis. We believe that the standardization of terminology will allow meaningful comparisons between future studies in women with an ultrasound diagnosis of endometriosis and should facilitate multicenter research. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Consenso , Endometriosis/diagnóstico por imagen , Enfermedades Peritoneales/diagnóstico por imagen , Ultrasonografía , Endometriosis/patología , Femenino , Humanos , Pelvis/patología , Enfermedades Peritoneales/patología , Guías de Práctica Clínica como Asunto
3.
Anim Genet ; 47(1): 81-90, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26537786

RESUMEN

Catfish is the leading aquaculture species in the United States. The interspecific hybrid catfish produced by mating female channel catfish with male blue catfish outperform both of their parent species in a number of traits. However, mass production of the hybrids has been difficult because of reproductive isolation. Investigations of genome structure and organization of the hybrids provide insights into the genetic basis for maintenance of species divergence in the face of gene flow, thereby helping develop strategies for introgression and efficient production of the hybrids for aquaculture. In this study, we constructed a high-density genetic linkage map using the hybrid catfish system with the catfish 250K SNP array. A total of 26,238 SNPs were mapped to 29 linkage groups, with 12,776 unique marker positions. The linkage map spans approximately 3240 cM with an average intermarker distance of 0.25 cM. A fraction of markers (986 of 12,776) exhibited significant deviation from the expected Mendelian ratio of segregation, and they were clustered in major genomic blocks across 15 LGs, most notably LG9 and LG15. The distorted markers exhibited significant bias for maternal alleles among the backcross progenies, suggesting strong selection against the blue catfish alleles. The clustering of distorted markers within genomic blocks should lend insights into speciation as marked by incompatibilities between the two species. Such findings should also have profound implications for understanding the genomic evolution of closely related species as well as the introgression of hybrid production programs in aquaculture.


Asunto(s)
Mapeo Cromosómico , Ligamiento Genético , Ictaluridae/genética , Polimorfismo de Nucleótido Simple , Animales , Femenino , Reordenamiento Génico , Marcadores Genéticos , Ictaluridae/clasificación , Masculino
4.
Int J Obstet Anesth ; 55: 103899, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37329691

RESUMEN

BACKGROUND: Spinal anaesthesia, the most common form of anaesthesia for caesarean section, leads to sympathetic blockade and profound maternal hypotension resulting in adverse maternal and neonatal outcomes. Hypotension, nausea and vomiting remain common but until the publication of the National Institute of Health and Care Excellence (NICE) 2021 guidance, no national guideline existed on how best to manage maternal hypotension following spinal anaesthesia for caesarean section. A 2017 international consensus statement recommended prophylactic vasopressor administration to maintain a systolic blood pressure of >90% of an accurate pre-spinal value, and to avoid a drop to <80% of this value. This survey aimed to assess regional adherence to these recommendations, the presence of local guidelines for management of hypotension during caesarean section under spinal anaesthesia, and the individual clinician's treatment thresholds for maternal hypotension and tachycardia. METHODS: The West Midlands Trainee-led Research in Anaesthesia and Intensive Care Network co-ordinated surveys of obstetric anaesthetic departments and consultant obstetric anaesthetists across 11 National Health Service Trusts in the Midlands, England. RESULTS: One-hundred-and-two consultant obstetric anaesthetists returned the survey and 73% of sites had a policy for vasopressor use; 91% used phenylephrine as the first-line drug but a wide range of recommended delivery methods was noted and target blood pressure was only listed in 50% of policies. Significant variation existed in both vasopressor delivery methods and target blood pressures. CONCLUSIONS: Although NICE has since recommended prophylactic phenylephrine infusion and a target blood pressure, the previous international consensus statement was not adhered to routinely.


Asunto(s)
Anestesia Obstétrica , Anestesia Raquidea , Cesárea , Hipotensión , Vasoconstrictores , Humanos , Femenino , Embarazo , Adulto , Hipotensión/etiología , Anestesia Raquidea/efectos adversos , Anestesia Obstétrica/efectos adversos , Reino Unido , Encuestas y Cuestionarios , Vasoconstrictores/administración & dosificación , Vasoconstrictores/efectos adversos
5.
Colorectal Dis ; 13(9): 1040-3, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20478004

RESUMEN

AIM: Anal cushions are connective tissue complexes thought to be involved in anal continence. This study aimed to assess them in continent subjects. METHOD: Continent women undergoing a transvaginal ultrasound scan for gynaecological reasons were included. The anal cushions were visualized at the mid-canal level. The cross-sectional area within the internal anal sphincter (Area 1) and the area enclosed within the anal cushions (Area 2) were measured and a Cushion:Canal (C:C) ratio was derived for each patient. The measurements were repeated in the semi-erect position. RESULTS: One hundred and two patients with a median age of 41 (IQR 32-49) years were included. The median C:C ratio was 0.68 (IQR 0.61-0.73). Inter-observer error was 0.98 and intra-observer error was 0.99. There was no significant correlation between age and C:C ratio. The C:C ratio was significantly higher in parous than in nulliparous women (P = 0.04). A history of obstetric trauma or minimal haemorrhoidal symptoms did not influence C:C ratio. There was a significant increase in C:C ratio in the erect position. (P = 0.04). CONCLUSION: There was a wide range of variability in the measurement of anal cushions in normal continent women. These were not influenced by age.


Asunto(s)
Canal Anal/anatomía & histología , Canal Anal/diagnóstico por imagen , Postura , Adulto , Endosonografía , Incontinencia Fecal/etiología , Femenino , Humanos , Persona de Mediana Edad , Variaciones Dependientes del Observador , Estadísticas no Paramétricas
6.
Theriogenology ; 149: 62-71, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32247214

RESUMEN

For externally fertilizing fishes, interactions between male and female gametes have been shown to have remarkable impacts on sperm performance. Ovarian fluid (OF) and its ability to alter the swimming behavior of fish sperm makes it a determining factor of fertility. With the expansion of channel catfish (Ictalurus punctatus) ♀ × blue catfish (Ictalurus furcatus) ♂ hybrid aquaculture, it is essential to understand the impacts during fertilization and the magnitude such gametic interactions have on sperm performance and subsequent male fertility potential. This study was conducted to address the following: 1) activate blue catfish sperm with/without channel catfish OF to determine impacts on sperm performance and 2) assess if sperm behave differently when activated in the OF from individual females. Sperm (n = 4 males) were activated without OF (control) and with diluted OF from unique females (n = 6), creating 24 experimental crosses. Sperm motility (%), velocity (VCL), and longevity were analyzed using computer assisted sperm analyses software. With OF incorporated in the activation media, sperm velocity was significantly higher than the control at 10, 20, and 30 s post-activation. OF did not have an impact on motility for any females at 10 s and 20 s post-activation but became significantly higher than the control at 30 s. In all cases, OF treatments greatly increased longevity. Male × female interactions were highly significant, such that motility, velocity, and longevity were dependent on specific male-female pairs. This information shows that OF should be incorporated in aquatic media to simulate natural spawning conditions and accurately assess the fluid mechanics of sperm propulsion for each male. Additionally, there are mechanisms that drive gamete interactions that need to be explored further, which may improve selection of male-female pairs for in-vitro fertilization. On a broad scale, our results also help to shed light on the complexities of fertilization and fish reproduction overall, which may have implications for recruitment variability and recovery strategies of threatened and/or endangered freshwater species.


Asunto(s)
Fertilidad/fisiología , Ictaluridae/fisiología , Ovario/fisiología , Reproducción/fisiología , Espermatozoides/fisiología , Animales , Acuicultura/métodos , Supervivencia Celular/fisiología , Líquido Extracelular/fisiología , Femenino , Masculino , Motilidad Espermática/fisiología , Interacciones Espermatozoide-Óvulo/fisiología
7.
Br J Surg ; 96(6): 680-4, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19384910

RESUMEN

BACKGROUND: Faecal incontinence affects a heterogeneous population and aetiology can be multifactorial. In a subset of patients the aetiology remains idiopathic despite standard investigations. Anal cushions are important in normal continence, but have rarely been studied. The aim of this study was to measure the size of the anal cushions and to evaluate their role in patients with idiopathic faecal incontinence. METHODS: Women in whom idiopathic faecal incontinence was diagnosed after standard anorectal investigations underwent transvaginal ultrasonography. The area of the anal cushions was measured and a cushion : canal (C : C) ratio derived, which was compared with that in a control group of women without faecal incontinence. RESULTS: Some 21 patients with incontinence (median age 60 years) and 102 asymptomatic controls (median age 41 years) underwent scanning. The median (interquartile range) C : C ratio in the symptomatic group was significantly lower than that for controls (0.57 (0.54-0.66) versus 0.68 (0.61-0.73) respectively; P = 0.001). C : C ratio was not influenced by age (r = 0.023, P = 0.821). CONCLUSION: The C : C ratio was reduced in patients with idiopathic faecal incontinence.


Asunto(s)
Canal Anal/patología , Tejido Conectivo/fisiología , Incontinencia Fecal/etiología , Canal Anal/diagnóstico por imagen , Canal Anal/fisiopatología , Estudios de Casos y Controles , Incontinencia Fecal/diagnóstico por imagen , Incontinencia Fecal/fisiopatología , Femenino , Humanos , Manometría , Persona de Mediana Edad , Calidad de Vida , Recurrencia , Índice de Severidad de la Enfermedad , Ultrasonografía
8.
Mol Cell Biol ; 8(7): 2722-9, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3043192

RESUMEN

A previous study demonstrated the ability of a synthetic peptide homologous to the simian virus 40 T-antigen nuclear transport signal to induce the nuclear transport of carrier proteins and the dependence of peptide-induced transport on a positive charge at the lysine corresponding to amino acid 128 of T antigen. In this investigation synthetic peptides were utilized to examine the effect on transport of amino acid substitutions within the T-antigen nuclear transport signal. Nuclear transport was evaluated by immunofluorescence after microinjection of protein-peptide conjugates into the cytoplasm of mammalian cells. Substitution of other basic amino acids at position 128 revealed a hierarchy for nuclear transport. The rate of nuclear transport was most rapid when a lysine was at position 128 followed in descending order by arginine, D-lysine, ornithine, and p-aminophenylalanine. Peptide-induced nuclear transport was dependent upon a positively charged amino acid at positions 128 and 129, since substitutions of neutral asparagines at these positions abolished transport. However, partial transport was observed with the peptide having an asparagine at position 128 when a high number of peptides were conjugated to the carrier protein.


Asunto(s)
Antígenos Transformadores de Poliomavirus/farmacología , Núcleo Celular , Proteínas/farmacocinética , Aminoácidos/metabolismo , Animales , Antígenos Transformadores de Poliomavirus/síntesis química , Antígenos Transformadores de Poliomavirus/metabolismo , Transporte Biológico/efectos de los fármacos , Línea Celular , Núcleo Celular/metabolismo , Chlorocebus aethiops , Técnica del Anticuerpo Fluorescente , Membranas Intracelulares/metabolismo , Riñón , Microinyecciones , Péptidos/síntesis química
10.
Genetics ; 165(2): 687-94, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14573480

RESUMEN

Catfish is the major aquaculture species in the United States. The hybrid catfish produced by crossing channel catfish females with blue catfish males exhibit a number of desirable production traits, but their mass production has been difficult. To introduce desirable genes from blue catfish into channel catfish through introgression, a genetic linkage map is helpful. In this project, a genetic linkage map was constructed using amplified fragment length polymorphism (AFLP). A total of 607 AFLP markers were analyzed using 65 primer combinations and an interspecific backcross resource family. A total of 418 AFLP markers were assigned to 44 linkage groups. Among the remaining 189 markers, 101 were not used because of significant segregation distortion, 29 were unlinked, and 59 were eliminated because they span very large distances. The 418 AFLP markers covered 1593 cM Kosambi. The AFLP markers showed a high level of clustering that appears to be related to certain primer combinations. This linkage map will serve as the basis for mapping a greater number of markers to provide a map with high enough resolution for it to be useful for selective breeding programs using introgression.


Asunto(s)
Mapeo Cromosómico , Hibridación Genética , Ictaluridae/genética , Animales , Marcadores Genéticos
11.
J Bone Joint Surg Br ; 87(2): 191-5, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15736741

RESUMEN

We present six patients with chronic dislocation of the elbow who were treated by primary semiconstrained total elbow arthroplasty. All were women with a mean age of 65 years (51 to 76), the mean interval between dislocation and surgery was 17 weeks (5 to 52) and the mean follow-up 58 months (24 to 123). The most dramatic improvement was in function. The mean American Shoulder and Elbow Surgeon score was 5.2 times better (p < 0.001) and the mean total range of movement increased from 33 degrees to 121 degrees (p < 0.001) after operation. Three patients developed wear of polyethylene. One required revision for a periprosthetic fracture, and another required a bushing exchange. Primary semiconstrained elbow arthroplasty provides significant, predictable functional improvement. Potential solutions for wear of polyethylene include a different operative technique or design of implant. Despite the high incidence of such wear, total elbow arthroplasty should be considered as a viable treatment option for chronic dislocation of the elbow in elderly patients.


Asunto(s)
Traumatismos del Brazo/cirugía , Artroplastia de Reemplazo/métodos , Lesiones de Codo , Luxaciones Articulares/cirugía , Anciano , Traumatismos del Brazo/diagnóstico por imagen , Traumatismos del Brazo/fisiopatología , Enfermedad Crónica , Articulación del Codo/fisiopatología , Articulación del Codo/cirugía , Femenino , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/fisiopatología , Fracturas Óseas/cirugía , Humanos , Luxaciones Articulares/diagnóstico por imagen , Luxaciones Articulares/fisiopatología , Persona de Mediana Edad , Dimensión del Dolor/métodos , Polietileno , Complicaciones Posoperatorias/etiología , Radiografía , Rango del Movimiento Articular , Estudios Retrospectivos , Resultado del Tratamiento
12.
Gene ; 252(1-2): 173-81, 2000 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-10903449

RESUMEN

The alpha-actin gene of channel catfish (Ictalurus punctatus) was cloned and sequenced. The gene has a similar organization and exhibited a high level of sequence similarity to those from other vertebrate animals. The upstream region of the alpha-actin gene included a TATA box, a CAAT box, three E-boxes, and a CArG box. Nested deletion segments containing these transcriptional motifs were fused to the reporter gene chloramphenicol acetyl transferase (CAT). Transfection of the clones into C2C12 cells indicated that all these motifs are required for transcriptional activities. The channel catfish alpha-actin gene is associated with two distinct short interspersed repetitive elements (SINEs). The first SINE element showed high levels of sequence similarity to the zebrafish Mermaid element, while the second SINE element is not similar to the Mermaid element except for an 8bp sequence CCCCGTGC suggesting their evolutionary linkage. However, the second SINE element appeared to co-exist with the Mermaid element in most cases and therefore was designated as the Merman element. Approximately 9000 copies and 1200 copies of the Mermaid and Merman elements exist per haploid channel catfish genome, respectively. BLAST searches indicated that both the Mermaid and the Merman elements were frequently associated with gene sequences, mostly those of aquatic animals, suggesting their evolutionary origin in association with aquatic organisms and their function in shaping the evolution of genomes in aquatic animals.


Asunto(s)
Actinas/genética , Ictaluridae/genética , Elementos de Nucleótido Esparcido Corto/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Línea Celular , Cloranfenicol O-Acetiltransferasa/genética , Cloranfenicol O-Acetiltransferasa/metabolismo , ADN/química , ADN/genética , ADN/aislamiento & purificación , Exones , Genes/genética , Intrones , Datos de Secuencia Molecular , Músculo Esquelético/química , Regiones Promotoras Genéticas/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Análisis de Secuencia de ADN , Eliminación de Secuencia , Homología de Secuencia de Ácido Nucleico
13.
Gene ; 261(2): 373-82, 2000 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-11167026

RESUMEN

Expressed sequence tag (EST) analysis was conducted using a complementary DNA (cDNA) library made from the brain mRNA of channel catfish (Ictalurus punctatus). As part of our transcriptome analysis in catfish to develop molecular reagents for comparative functional genomics, here we report analysis of 1201 brain cDNA clones. Of the 1201 clones, 595 clones (49.5%) were identified as known genes by BLAST searches and 606 clones (50.5%) as unknown genes. The 595 clones of known gene products represent transcripts of 251 genes. These known genes were categorized into 15 groups according to their biological functions. The largest group of known genes was the genes involved in translational machinery (21.4%) followed by mitochondrial genes (6.2%), structural genes (3.1%), genes homologous to sequences of unknown functions (2.3%), enzymes (2.7%), hormone and regulatory proteins (2.5%), genes involved in immune systems (2.1%), genes involved in sorting, transport, and metal metabolism (1.8%), transcriptional factors and DNA repair proteins (1.6%), proto-oncogenes (1.2%), lipid binding proteins (1.2%), stress-induced genes (0.7%), genes homologous to human genes involved in mental diseases (0.6%), and development or differentiation-related genes (0.3%). The number of genes represented by the 606 clones of unknown genes is not known at present, but the high percentage of clones showing no homology to any known genes in the GenBank databases may indicate that a great number of novel genes exist in teleost brain.


Asunto(s)
Perfilación de la Expresión Génica , Ictaluridae/genética , Animales , Encéfalo/metabolismo , ADN Complementario/química , ADN Complementario/genética , ADN Mitocondrial/genética , Etiquetas de Secuencia Expresada , Regulación de la Expresión Génica , Biblioteca de Genes , Datos de Secuencia Molecular , ARN de Transferencia de Valina/genética , Proteínas Ribosómicas/genética , Análisis de Secuencia de ADN , Transcripción Genética
14.
Immunol Res ; 29(1-3): 253-68, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15181287

RESUMEN

For a number of years the pathogenesis of AIDS was thought to be essentially related to direct human immunodeficiency virus (HIV)-mediated killing of CD4+ T cells. More recently, attention has shifted to pathogenic models that emphasize the role of generalized immune system activation and the excess apoptosis of uninfected T cells in inducing HIV-associated CD4+ T-cell depletion. The main focus of our research is to better define the determinants and the consequences of these "indirect" mechanisms of immunodeficiency by studying both HIV-infected patients and nonhuman primates infected with simian immunodeficiency virus (SIV). We have discovered that pathogenic models of retroviral infections of primates (i.e., HIV infection in humans and SIV infection in rhesus macaques) are associated with the presence of a set of perturbations of normal cell-cycle control in T lymphocytes. These perturbations, to which we collectively refer to as cell-cycle dysregulation, or CCD, may represent an important biological link between chronic immune activation and excess apoptosis and therefore may play a significant role in the pathogenesis of AIDS. A better understanding of the determinants and consequences of CCD may pave the way for the introduction of new therapeutic strategies to be used in addition to standard antiretroviral therapy in HIV-infected patients.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/inmunología , Linfocitos T CD4-Positivos/inmunología , Animales , Apoptosis/inmunología , Linfocitos T CD4-Positivos/citología , Ciclo Celular/inmunología , Ciclo Celular/fisiología , Supresión Clonal/inmunología , Ciclina B/metabolismo , VIH/inmunología , VIH/patogenicidad , Humanos , Interleucina-2/inmunología , Fosfoproteínas/metabolismo , Proteínas de Unión al ARN/metabolismo , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Virus de la Inmunodeficiencia de los Simios/patogenicidad , Nucleolina
15.
J Mol Endocrinol ; 21(2): 121-9, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9801455

RESUMEN

Expressed sequence tag (EST) analysis was adopted to address physiological changes after injection of carp pituitary extract for induction of ovulation. ESTs were analyzed from cDNA libraries constructed from mRNA isolated from channel catfish (Ictalurus punctatus) pituitaries before and after induction of ovulation by injection of carp pituitary extract. One hundred randomly picked clones were analyzed. Of the sequences generated, a large percentage (59%) of ESTs were identified as known genes by identity comparisons. These 59 clones of known gene products represent transcriptional products of 30 genes. The 41 clones of unknown gene products represent 33 genes. Expression of gonadotropin (GtH) alpha-subunit (149%) and prolactin (176%) was slightly enhanced as a result of induced ovulation. Large increases in frequencies of several peptide hormones were observed as a result of induced ovulation: GtH beta-I, 486%; GtH beta-II, 933%; growth hormone, 393%; proopiomelanocortin (POMC), 345%. POMC represented about 21% of all transcriptional activity in the pituitaries after induced ovulation. This is the first study addressing physiological changes after injection of carp pituitary extract, a procedure widely used in catfish hatcheries.


Asunto(s)
Ictaluridae/fisiología , Inducción de la Ovulación , Hipófisis/metabolismo , Transcripción Genética , Animales , Biotecnología , Carpas , ADN Complementario , Etiquetas de Secuencia Expresada , Hormonas Hipofisarias/metabolismo , ARN Mensajero/genética , Reproducción/genética , Reproducción/fisiología
16.
J Immunol Methods ; 156(2): 137-49, 1992 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-1474251

RESUMEN

In this report, we have described methods to improve the efficiency of coupling synthetic peptides to keyhole limpet hemocyanin (KLH) and for the analysis of the composition of the resulting peptide-protein conjugates. KLH was first dissolved in buffers containing 3 M guanidine hydrochloride to maintain solubility and derivatized with either of two water soluble, heterobifunctional crosslinkers, m-maleimido-benzoyl-N-hydroxy-sulfosuccinimide ester (SMBS), or sulfosuccinimidyl 4-(N-maleimidomethyl)cyclohexane-1-carboxylate (SSMCC) (300:1 molar excess over KLH). Synthetic peptides containing an amino terminal cysteine were then crosslinked to the modified KLH via sulfhydryl reaction with the crosslinker maleimide groups. Following dialysis to remove free peptide, the amino acid composition of the conjugate was determined. The molar ratio of peptide to protein within the conjugate was obtained by comparing the conjugate composition with that of both the KLH and peptide analyzed separately, and by a multiple regression, least squares analysis of the data. This method is generally applicable to the analysis of the molar ratios of protein-protein conjugates of unknown sequence or composition, and requires only the prior determination of the experimental amino acid composition of each component of the conjugate separately.


Asunto(s)
Hemocianinas/química , Péptidos/análisis , Animales , Antígenos VIH/química , Moluscos , Péptidos/química , Péptidos/inmunología , Análisis de Regresión
17.
Biotechnol Annu Rev ; 2: 205-36, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-9729110

RESUMEN

Since 1985, transgenic fish have been successfully produced by microinjecting or electroporating desired foreign DNA into unfertilized or newly fertilized eggs using many different fish species. More recently, transgenic fish have also been produced by infecting newly fertilized eggs with pantropic, defective retroviral vectors carrying desired foreign DNA. These transgenic fish can serve as excellent experimental models for basic scientific investigations as well as in biotechnological applications. In this paper, we will review the current status of the transgenic fish research and its potential application in basic and applied research.


Asunto(s)
Animales Modificados Genéticamente/genética , Biotecnología/métodos , Peces/genética , Proyectos de Investigación , Animales , Electroporación , Monitoreo del Ambiente , Técnicas de Transferencia de Gen , Vectores Genéticos , Hormona del Crecimiento/genética , Factor I del Crecimiento Similar a la Insulina/genética , Microinyecciones
19.
Surg Clin North Am ; 74(4): 913-21; discussion 923-9, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8047949

RESUMEN

It is apparent that no inherent dilemma exists in training surgeons in both open and laparoscopic techniques. The important point is that surgeons are trained: a solid foundation in the basic sciences, well-developed technical skills, a large clinical experience on which to base future decisions, and the insight to know when one's skills require improvement. The principles of biliary surgery should be adhered to, and in one's haste to become proficient at laparoscopic techniques, one must not abandon the most basic of these-the unequivocal identification of all structures before ligating, dividing, clipping, or otherwise sacrificing tissues.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Biliar , Educación de Postgrado en Medicina/métodos , Cirugía General/educación , Laparoscopía , Procedimientos Quirúrgicos del Sistema Biliar/métodos , Colecistectomía Laparoscópica , Humanos , Estados Unidos
20.
Mar Biotechnol (NY) ; 3(3): 205-17, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-14961357

RESUMEN

Pituitary growth hormone (GH), prolactin (PRL), and somatolactin (SL) messenger RNA levels in channel catfish (Ictalurus punctatus) were examined under various environmental and physiological conditions. Catfish were sampled following salinity challenge, during the winter (December) and spring or summer (April or July), and at different sizes (15-18 g, 620-664 g, and 956-1134 g). When catfish (956-1134 g) were transferred from freshwater to saline water containing 8 ppt NaCl, their plasma [Na(+)] increased significantly above values in the freshwater control group until they were transferred back to freshwater. Pituitary GH mRNA levels were low for the first 24 hours following transfer to saline water, but thereafter were significantly elevated above control values until the fish were transferred back to freshwater. Pituitary GH mRNA levels were highest in July and lowest in December. Growth hormone mRNA levels were also elevated in the size groups 15-18 g and 956-1134 g in July when compared with December values. Pituitary PRL mRNA levels increased for the first 24 hours following transfer to saline water (956-1134 g), but thereafter were significantly lower than control values until the fish were transferred back to freshwater. Pituitary PRL mRNA levels were highest in April and July and lowest in December, and were also elevated in the size groups 620-664 g and 956-1134 g. Pituitary SL mRNA levels were unaffected in catfish transferred to saline water; however, levels were significantly elevated in catfish of the 956-1134-g size group sampled in April when compared with December. These results suggest the involvement of GH in adaptation to brackish water and of PRL in adaptation to freshwater in the catfish, and seasonal and size-related differences in pituitary GH, PRL, and SL mRNA levels.

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