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1.
Georgian Med News ; (348): 36-39, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38807387

RESUMO

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.


Assuntos
Nascimento Prematuro , Progesterona , Humanos , Feminino , Gravidez , Progesterona/administração & dosagem , Progesterona/uso terapêutico , Nascimento Prematuro/epidemiologia , Estudos Transversais , Adulto , Prevalência , Adulto Jovem , Progestinas/administração & dosagem , Progestinas/uso terapêutico , Fatores de Risco
2.
Int J Obstet Anesth ; 55: 103899, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37329691

RESUMO

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.


Assuntos
Anestesia Obstétrica , Raquianestesia , Cesárea , Hipotensão , Vasoconstritores , Humanos , Feminino , Gravidez , Adulto , Hipotensão/etiologia , Raquianestesia/efeitos adversos , Anestesia Obstétrica/efeitos adversos , Reino Unido , Inquéritos e Questionários , Vasoconstritores/administração & dosagem , Vasoconstritores/efeitos adversos
3.
Theriogenology ; 149: 62-71, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32247214

RESUMO

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.


Assuntos
Fertilidade/fisiologia , Ictaluridae/fisiologia , Ovário/fisiologia , Reprodução/fisiologia , Espermatozoides/fisiologia , Animais , Aquicultura/métodos , Sobrevivência Celular/fisiologia , Líquido Extracelular/fisiologia , Feminino , Masculino , Motilidade dos Espermatozoides/fisiologia , Interações Espermatozoide-Óvulo/fisiologia
4.
Ultrasound Obstet Gynecol ; 48(3): 318-32, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27349699

RESUMO

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.


Assuntos
Consenso , Endometriose/diagnóstico por imagem , Doenças Peritoneais/diagnóstico por imagem , Ultrassonografia , Endometriose/patologia , Feminino , Humanos , Pelve/patologia , Doenças Peritoneais/patologia , Guias de Prática Clínica como Assunto
5.
Anim Genet ; 47(1): 81-90, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26537786

RESUMO

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.


Assuntos
Mapeamento Cromossômico , Ligação Genética , Ictaluridae/genética , Polimorfismo de Nucleotídeo Único , Animais , Feminino , Rearranjo Gênico , Marcadores Genéticos , Ictaluridae/classificação , Masculino
6.
J Anim Sci ; 92(5): 1850-65, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24663183

RESUMO

Head length, head depth, head width, body depth, body width, caudal depth, and caudal width and total length and BW were measured for 71 backcross full sibs between the interspecific backcross F1 (female channel catfish [Ictalurus punctatus] × male blue catfish [Ictalurus furcatus]) female × blue catfish male. Body measurements were corrected for both size and the relationship between relative body shape and size, which is critical but usually ignored in fish research. Amplified fragment length polymorphism analysis was used for construction of a QTL map with 44 linkage groups. Eleven of 44 linkage groups had at least 1 significant QTL (P ≤ 0.05) and 11 of 44 at P = 0.10. Linkage group 19 was unique as it had multiple QTL for every trait measured, except for caudal width for which no QTL was identified on any linkage group. Approximately half of the markers measured were associated with positive effects (increase in size) on the traits and half had negative effects (decrease in size). Linkage groups 5, 9, 18, 20, 39, and 40 were significant for multiple traits and always had a trait negative effect. Total length is represented on the map by the most linkage groups and the most markers. The linkage relationships found among BW, total length, and the 7 morphometric traits indicated that multiple trait marker-assisted selection to simultaneously increase BW body depth, body width, and caudal depth while decreasing the head traits with the goal to increase body weight and carcass yield would be very difficult. Multiple genetic enhancement approaches would likely be needed to simultaneously improve BW and body conformation.


Assuntos
Peixes-Gato/crescimento & desenvolvimento , Peixes-Gato/genética , Hibridização Genética , Locos de Características Quantitativas/genética , Animais , Peso Corporal/genética , Mapeamento Cromossômico , Feminino , Ligação Genética , Masculino
7.
Ultrasound ; 22(3): 141-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27433211

RESUMO

The aims of the study were to evaluate whether three-dimensional transvaginal ultrasound (3D TV US) is superior to two-dimensional transvaginal ultrasound (2D TV US) at visualising intrauterine devices and determining their position. This prospective study included 52 participants with an intrauterine device fitted, who underwent 2D TV US and 3D TV US. 2D TV US and 3D-reconstructed coronal images were reviewed by two gynaecological radiologists to assess ease of visualisation and position of the intrauterine devices. Statistical analysis was performed using Wilcoxon signed-rank, McNemar and Chi-squared tests. The inter-observer agreement was measured using Cohen's Kappa. Intrauterine device visualisation scores were significantly higher with 2D TV US compared with 3D TV US (Radiologist 1 p = <0.001, Radiologist 2 p = 0.007). A significant number of T-arms appeared to perforate into the adjacent myometrium on the 3D-reconstructed coronal image, but were normal on the 2D images (Radiologist 1 p = <0.001, Radiologist 2 p = 0.008). Radiologist 1 found 19 perforated T-arms on 3D TV US compared with four on 2D TV US. Radiologist 2 found 13 perforated T-arms on 3D TV US compared with five on 2D TV US. Both radiologists agreed on the positions of the intrauterine devices substantially with 3D TV US (Kappa = 0.69) and moderately with 2D TV US (Kappa = 0.55). The 3D TV US did not visualise an intrauterine device better than 2D TV US. The 3D-reconstructed coronal image of the uterus can reliably display cases of T-arm perforation into the adjacent myometrium, which could be missed on 2D TV US images. The 3D TV US should be used in addition to 2D TV US in all cases where an intrauterine device is under evaluation.

9.
Colorectal Dis ; 13(9): 1040-3, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20478004

RESUMO

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.


Assuntos
Canal Anal/anatomia & histologia , Canal Anal/diagnóstico por imagem , Postura , Adulto , Endossonografia , Incontinência Fecal/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estatísticas não Paramétricas
10.
Br J Surg ; 96(6): 680-4, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19384910

RESUMO

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.


Assuntos
Canal Anal/patologia , Tecido Conjuntivo/fisiologia , Incontinência Fecal/etiologia , Canal Anal/diagnóstico por imagem , Canal Anal/fisiopatologia , Estudos de Casos e Controles , Incontinência Fecal/diagnóstico por imagem , Incontinência Fecal/fisiopatologia , Feminino , Humanos , Manometria , Pessoa de Meia-Idade , Qualidade de Vida , Recidiva , Índice de Gravidade de Doença , Ultrassonografia
11.
Eur J Surg Oncol ; 34(4): 403-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17604939

RESUMO

AIMS: To assess the feasibility, pharmacokinetics and maximum tolerable frequency (MTF) of intraperitoneal (IP) 5-fluorouracil and leucovorin (FU/LV) added, as a regional boost, to intravenous chemotherapy after resection of gastrointestinal cancer. METHODS: Fifty-three patients were recruited following gastrointestinal cancer resection (43 colon; 10 stomach/small bowel) with serosal involvement. Peritoneal ports were implanted and IP fluid distribution evaluated ultrasonically. Twelve patients were studied for pharmacokinetics; 44 (41 evaluable) for MTF. Treatment was weekly intravenous bolus FU/LV for 6 months; to this was added IP FU/LV (400/20 mg/m(2) in 1500 ml 4% icodextrin) with increasing frequency from 4 weekly to 1 weekly in four successive cohorts. RESULTS: Peritoneal fluid distribution was excellent. Intraperitoneal FU exposure (AUC) after IP treatment was >1000-fold plasma AUC after IP treatment (regional pharmacokinetic advantage), and >100-fold plasma AUC after intravenous treatment (regional therapeutic advantage). IP therapy was well tolerated if given every 4, 3 or 2 weeks, but not weekly: 11/13, 7/8, 10/13 and 0/7 patients respectively completed treatment without IP modification in these cohorts. Problems with peritoneal access occurred in 20% of patients. CONCLUSION: Adding fortnightly IP FU/LV to a standard intravenous regimen is safe, tolerable and provides high peritoneal FU exposure. More reliable peritoneal access is needed to improve the feasibility of this otherwise promising therapeutic approach.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Fluoruracila/administração & dosagem , Neoplasias Gastrointestinais/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica , Esquema de Medicação , Estudos de Viabilidade , Feminino , Humanos , Infusões Intravenosas , Infusões Parenterais , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
12.
Dis Colon Rectum ; 49(9): 1410-3, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16729219

RESUMO

PURPOSE: The anal cushions are believed to contribute to the anal continence mechanism. Transvaginal ultrasound previously has been used to visualize the anal sphincters. Using this method, visualization of the anal cushions has been described but no quantitation of the cushions has been undertaken. Because impairment of the anal cushion function may lead to anal incontinence, this study was designed to evaluate the use of transvaginal ultrasound to measure the anal cushions. METHODS: Patients attending a gynecologic ultrasound list were recruited into the study. By measuring cross-sectional areas, a cushion:canal ratio was calculated. RESULTS: Fifty females were studied. Results showed that the area enclosed within the internal anal sphincter had a median of 2.37 cm(2) (interquartile range, 1.76-2.61). The cushion:canal ratio was 0.66 (interquartile range, 0.57-0.7). Interobserver error was 0.98 and intraobserver error 0.99. CONCLUSIONS: In this pilot study, we conclude that transvaginal ultrasonography is a reliable method of measuring the anal cushions in healthy control subjects. A narrow normal range can be established. This may be compared later with anal cushion size in patients who have symptoms of incontinence and may be used to assess changes in the size of the cushions in response to recently described anal cushion bulking agents.


Assuntos
Canal Anal/diagnóstico por imagem , Canal Anal/anatomia & histologia , Feminino , Humanos , Valores de Referência , Ultrassonografia/métodos
13.
J Bone Joint Surg Br ; 87(2): 191-5, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15736741

RESUMO

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.


Assuntos
Traumatismos do Braço/cirurgia , Artroplastia de Substituição/métodos , Lesões no Cotovelo , Luxações Articulares/cirurgia , Idoso , Traumatismos do Braço/diagnóstico por imagem , Traumatismos do Braço/fisiopatologia , Doença Crônica , Articulação do Cotovelo/fisiopatologia , Articulação do Cotovelo/cirurgia , Feminino , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/fisiopatologia , Fraturas Ósseas/cirurgia , Humanos , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/fisiopatologia , Pessoa de Meia-Idade , Medição da Dor/métodos , Polietileno , Complicações Pós-Operatórias/etiologia , Radiografia , Amplitude de Movimento Articular , Estudos Retrospectivos , Resultado do Tratamento
14.
Int J STD AIDS ; 15(7): 486-8, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15228736

RESUMO

We describe a rare cause of irregular vaginal bleeding due to a haemangioma of the uterine cervix. Clinical, ultrasound and MRI appearances are shown and options for management discussed.


Assuntos
Hemangioma/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adulto , Colposcopia , Feminino , Humanos , Hemorragia Uterina/etiologia
15.
Immunol Res ; 29(1-3): 253-68, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15181287

RESUMO

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.


Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Linfócitos T CD4-Positivos/imunologia , Animais , Apoptose/imunologia , Linfócitos T CD4-Positivos/citologia , Ciclo Celular/imunologia , Ciclo Celular/fisiologia , Deleção Clonal/imunologia , Ciclina B/metabolismo , HIV/imunologia , HIV/patogenicidade , Humanos , Interleucina-2/imunologia , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Vírus da Imunodeficiência Símia/patogenicidade , Nucleolina
16.
Genetics ; 165(2): 687-94, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14573480

RESUMO

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.


Assuntos
Mapeamento Cromossômico , Hibridização Genética , Ictaluridae/genética , Animais , Marcadores Genéticos
17.
Mol Genet Genomics ; 268(1): 87-95, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12242503

RESUMO

Aquatic ectotherms can adapt to a wide range of temperature changes, but the molecular mechanisms that underlie this adaptability are not well understood. We identified genes that are differentially expressed in the catfish ( Ictalurus punctatus) brain using a cDNA microarray approach to gain an initial understanding of adaptation to low temperature. Among 660 genes analyzed, 61 were differentially expressed when compared at 12 degrees C and 24 degrees C. Gene induction was rapid, occurring within 2 h of the temperature shift. The major categories of differentially expressed genes included (1) genes for chaperones such as Hsp70 and Hsp70/Hsp90 organizing protein; (2) genes for transcription factors and gene products involved in signal transduction pathways such as zinc-finger proteins, calmodulin kinase inhibitor, the nuclear autoantigen SG2NA, interferon regulatory factor 3, and inorganic pyrophosphatase; (3) genes involved in lipid metabolism such as TB2 and acyl CoA binding protein; and (4) genes involved in the translational machinery such as ribosomal proteins. Some genes were induced transiently, whereas others were induced in an enduring fashion. Several genes, primarily ribosomal protein genes, were down regulated, indicating reduced metabolic activities after extended incubation at the low temperature. Thus channel catfish respond to low temperature by adjusting expression of a large number of genes. The rapid induction of proteins involved in signal transductions and chaperones suggests that both de novo synthesis of cold-induced proteins and modification of existing proteins are required for adaptation and tolerance of catfish to low environmental temperature.


Assuntos
Aclimatação , Encéfalo/metabolismo , Temperatura Baixa , Regulação da Expressão Gênica , Ictaluridae/genética , Animais , Regulação para Baixo , Exposição Ambiental , Proteínas de Peixes/genética , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Tempo , Ativação Transcricional , Regulação para Cima
18.
Mar Biotechnol (NY) ; 4(6): 604-11, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14961235

RESUMO

The effect of rainbow trout growth hormone complementary DNA on body shape, dress-out yield, and body composition were assessed in the F1 and F2 generations of transgenic common carp (Cyprinus carpio). All measurements were compared with those for nontransgenic full-sibling common carp in their respective families, and the fish were communally evaluated in earthen ponds. The body weight and length were highly correlated (P <0.01) in both genotypes in all the families. Head morphometrics were negatively correlated (P <0.05) to weight and length of the fish. Various head, body, and caudal traits grew disproportionately faster in transgenic fish in both generations. The altered body shape of transgenic fish resulted in improved dressing percentage in the F2 generation. The carcass composition of transgenic muscle had a lower percentage of (P <0.01) moisture and lipids and higher (P <0.01) percentage of protein in both generations. Six of the 18 amino acids analyzed in F1 transgenic common carp muscle were higher F1 (P <0.05) than the control genotype; however, amino acid ratios were minimally changed. Also, the fatty acid profiles of both genotypes were minimally altered. Higher histidine and lysine ratios in the diet are recommended for maximum growth and health of transgenic common carp in intensive culture systems on the basis of essential amino acid ratios.

19.
Mar Biotechnol (NY) ; 3(3): 205-17, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-14961357

RESUMO

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.

20.
Gene ; 252(1-2): 173-81, 2000 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-10903449

RESUMO

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.


Assuntos
Actinas/genética , Ictaluridae/genética , Elementos Nucleotídeos Curtos e Dispersos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Cloranfenicol O-Acetiltransferase/genética , Cloranfenicol O-Acetiltransferase/metabolismo , DNA/química , DNA/genética , DNA/isolamento & purificação , Éxons , Genes/genética , Íntrons , Dados de Sequência Molecular , Músculo Esquelético/química , Regiões Promotoras Genéticas/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Análise de Sequência de DNA , Deleção de Sequência , Homologia de Sequência do Ácido Nucleico
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