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1.
Sci Rep ; 11(1): 19451, 2021 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593916

RESUMO

Assessing the body condition of wild animals is necessary to monitor the health of the population and is critical to defining a framework for conservation actions. Body condition indices (BCIs) are a non-invasive and relatively simple means to assess the health of individual animals, useful for addressing a wide variety of ecological, behavioral, and management questions. The Antillean manatee (Trichechus manatus manatus) is an endangered subspecies of the West Indian manatee, facing a wide variety of threats from mostly human-related origins. Our objective was to define specific BCIs for the subspecies that, coupled with additional health, genetic and demographic information, can be valuable to guide management decisions. Biometric measurements of 380 wild Antillean manatees captured in seven different locations within their range of distribution were obtained. From this information, we developed three BCIs (BCI1 = UG/SL, BCI2 = W/SL3, BCI3 = W/(SL*UG2)). Linear models and two-way ANCOVA tests showed significant differences of the BCIs among sexes and locations. Although our three BCIs are suitable for Antillean manatees, BCI1 is more practical as it does not require information about weight, which can be a metric logistically difficult to collect under particular circumstances. BCI1 was significantly different among environments, revealing that the phenotypic plasticity of the subspecies have originated at least two ecotypes-coastal marine and riverine-of Antillean manatees.


Assuntos
Tamanho Corporal , Ecótipo , Trichechus manatus/anatomia & histologia , Animais , Biometria , Feminino , Masculino
2.
Orthop Traumatol Surg Res ; 103(2): 199-202, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28089796

RESUMO

INTRODUCTION: The incidence of obesity has increased significantly worldwide. Our hypothesis was that patients with obesity have a more severe distal radius fracture and we realized a study to evaluate this correlation between obesity and severity of distal radius fractures caused by low-energy injuries. MATERIALS AND METHODS: A total of 114 patients with distal radius fracture were examined in a cross-sectional, observational study. Fractures were classified according to the international AO-Müller/Orthopedic Trauma Association (AO/OTA) classification in order to determine the severity. The patient's Body Mass Index (BMI) was calculated and a Pearson correlation was performed. RESULTS: The patients were predominantly female, and left side was more frequently affected. Most of the fractures were AO/OTA type A (71 patients). The majority of the involved patients in our study were overweighed or obese. We do not observe a direct correlation between grade of obesity and distal radius fracture severity. CONCLUSIONS: Based on the results of this study obesity and severity of distal radius fractures do not correlate. LEVEL OF EVIDENCE: Prognostic. Level IV.


Assuntos
Índice de Massa Corporal , Obesidade/complicações , Fraturas do Rádio/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índices de Gravidade do Trauma , Adulto Jovem
3.
Prenat Diagn ; 35(10): 999-1004, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26088833

RESUMO

OBJECTIVE: A novel algorithm to identify fetal microdeletion events in maternal plasma has been developed and used in clinical laboratory-based noninvasive prenatal testing. We used this approach to identify the subchromosomal events 5pdel, 22q11del, 15qdel, 1p36del, 4pdel, 11qdel, and 8qdel in routine testing. We describe the clinical outcomes of those samples identified with these subchromosomal events. METHODS: Blood samples from high-risk pregnant women submitted for noninvasive prenatal testing were analyzed using low coverage whole genome massively parallel sequencing. Sequencing data were analyzed using a novel algorithm to detect trisomies and microdeletions. RESULTS: In testing 175,393 samples, 55 subchromosomal deletions were reported. The overall positive predictive value for each subchromosomal aberration ranged from 60% to 100% for cases with diagnostic and clinical follow-up information. The total false positive rate was 0.0017% for confirmed false positives results; false negative rate and sensitivity were not conclusively determined. CONCLUSION: Noninvasive testing can be expanded into the detection of subchromosomal copy number variations, while maintaining overall high test specificity. In the current setting, our results demonstrate high positive predictive values for testing of rare subchromosomal deletions.


Assuntos
Deleção de Genes , Genoma Humano , Testes para Triagem do Soro Materno , Feminino , Humanos , Gravidez
4.
Am J Cancer Res ; 5(1): 466-71, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25628955

RESUMO

UNLABELLED: Hispanics in El Paso, TX, a large American-Mexican border city constitute 85% of the population. Limited cancer research has been conducted in this population. We sought to study the prevalence of BRCA mutations among Hispanic patients of Mexican origin, identify reported Mexican founder or recurrent mutations, and study the breast cancer characteristics in mutation carriers. METHODS: Hispanic women of Mexican descent with a personal history of breast cancer, who presented consecutively for genetic cancer risk assessment, were enrolled in an Institutional Review Board-approved registry and underwent BRCA testing based on national guidelines. The characteristics of tumors and patients with positive BRCA mutation were analyzed. RESULTS: 88 patients were screened; 18 patients (20%) were BRCA carriers. Among BRCA carriers, 72% were diagnosed with breast cancer at younger than 50 years, 61% had "Triple negative disease". BRCA carriers had a significantly higher Body Mass Index (BMI) than non-carriers. Thirteen patients had BRCA1 mutations and five had BRCA2 mutations. A total of 17 deleterious BRCA Mutations were observed. Seven have been previously reported as specific genes from Mexico as country of origin. Five new mutations in BRCA carriers of Mexican descent were identified. CONCLUSION: Hispanic breast cancer patients of Mexican origin present at a younger age, and have predominantly triple negative tumors and high BMI. We identified 5 new mutations not reported previously in Hispanic BRCA carriers of Mexican descent. Interestingly, 41% of BRCA mutations identified have been reported as recurrent mutations in Hispanic individuals from Mexico as the country of origin. A more cost-effective approach to initial screening of Hispanic individuals based on country of origin is desirable and would potentially decrease the number of cases requiring complete sequencing.

7.
J Clin Oncol ; 31(2): 210-6, 2013 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-23233716

RESUMO

PURPOSE: To determine the prevalence and type of BRCA1 and BRCA2 (BRCA) mutations among Hispanics in the Southwestern United States and their potential impact on genetic cancer risk assessment (GCRA). PATIENTS AND METHODS: Hispanics (n = 746) with a personal or family history of breast and/or ovarian cancer were enrolled in an institutional review board-approved registry and received GCRA and BRCA testing within a consortium of 14 clinics. Population-based Hispanic breast cancer cases (n = 492) enrolled in the Northern California Breast Cancer Family Registry, negative by sequencing for BRCA mutations, were analyzed for the presence of the BRCA1 ex9-12del large rearrangement. RESULTS: Deleterious BRCA mutations were detected in 189 (25%) of 746 familial clinic patients (124 BRCA1, 65 BRCA2); 21 (11%) of 189 were large rearrangement mutations, of which 62% (13 of 21) were BRCA1 ex9-12del. Nine recurrent mutations accounted for 53% of the total. Among these, BRCA1 ex9-12del seems to be a Mexican founder mutation and represents 10% to 12% of all BRCA1 mutations in clinic- and population-based cohorts in the United States. CONCLUSION: BRCA mutations were prevalent in the largest study of Hispanic breast and/or ovarian cancer families in the United States to date, and a significant proportion were large rearrangement mutations. The high frequency of large rearrangement mutations warrants screening in every case. We document the first Mexican founder mutation (BRCA1 ex9-12del), which, along with other recurrent mutations, suggests the potential for a cost-effective panel approach to ancestry-informed GCRA.


Assuntos
Neoplasias da Mama Masculina/genética , Neoplasias da Mama/genética , Genes BRCA1 , Genes BRCA2 , Mutação em Linhagem Germinativa , Hispânico ou Latino/genética , Neoplasias Ovarianas/genética , Adulto , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etnologia , Neoplasias da Mama Masculina/epidemiologia , Neoplasias da Mama Masculina/etnologia , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/etnologia , Prevalência , Sudoeste dos Estados Unidos/epidemiologia
8.
Oncogene ; 27(31): 4336-43, 2008 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-18372921

RESUMO

Doublet mutations in cancer are not well studied. We find that allelic somatic doublet mutations are present at high frequency in the epidermal growth factor receptor (EGFR) tyrosine kinase (TK) domain in lung cancers. When doublets from the literature are added, a total of 96 doublets are available for analysis. The frequency of doublets overall is 6%, which is sevenfold greater than that observed in normal tissue in mouse. All characterized doublets are allelic, and silent mutations occur rarely. About half of all doublets contain one or two of 12 distinct missense mutations at five amino acids: E709, G719, S768, T790 and L861. The mutations at these five amino acids are seldom reported as singlets. Moreover, when the common L858 target is included, more than one-third of EGFR doublets are one of five specific missense pairs: G719/E709, G719/S768, G719/L861, L858/E709 and L858/T790. Structure suggests function: The data imply that most EGFR doublets are NOT consistent with a 'driver and passenger' mutation mechanism. EGFR doublets are highly skewed relative to singlets, consistent with functional selection of two individually suboptimal mutations that, in combination, have enhanced oncogenic potential.


Assuntos
Receptores ErbB/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Mutação , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Aminoácidos/química , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Conformação Proteica , Proteínas Tirosina Quinases/química
9.
Gynecol Oncol ; 107(1 Suppl 1): S56-71, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17884153

RESUMO

Platinum-based chemotherapy has been the mainstay of treatment for advanced gynecological cancers following cytoreductive surgery and in radiation sensitization of cervical cancer. Despite its initial high overall clinical response rate, a significant number of patients develop resistance to platinum combination therapies. The precise mechanism of platinum-resistance is multifactorial and accumulation of multiple genetic changes may lead to the drug-resistant phenotype. Platinum chemotherapy exerts its cytotoxic effect by forming DNA adducts and subsequently inhibiting DNA replication. It is now clear that the nucleotide excision repair (NER) pathway repairs platinum-DNA adducts in cellular DNA. Evaluation of genetic polymorphisms in cancer susceptibility as one etiology for platinum resistance may help us to understand the significance of these factors in the identification of individuals at higher risk of developing resistance to anti-cancer drug therapies. In this review, we summarized the relevant studies, both in vitro and in vivo, that pertain to NER in ovarian cancer and platinum resistance. It is evident also that there are a few limited studies in genetic polymorphisms of NER and ovarian cancer. These studies reviewed suggest that concurrent up-regulation of genes involved in NER may be important in clinical resistance to platinum-based chemotherapy in ovarian cancer. In the future, larger and well-designed population-based studies will be needed for a more complete understanding of relevant genetic factors that may result in improved strategies for determining both chemotherapy choice and efficacy in patients with advanced ovarian and cervical cancer. Review II will focus on the NER pathway in cervical cancer and platinum sensitivity.


Assuntos
Antineoplásicos/farmacologia , Reparo do DNA/fisiologia , DNA de Neoplasias/genética , Compostos Organoplatínicos/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Dano ao DNA , Reparo do DNA/genética , DNA de Neoplasias/metabolismo , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Conformação de Ácido Nucleico
10.
Gynecol Oncol ; 107(1 Suppl 1): S223-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17825393

RESUMO

OBJECTIVE: Platinum-based chemotherapy exerts its cytotoxic effect by forming DNA adducts and subsequently inhibiting DNA replication. Removing platinum DNA adducts requires the nucleotide excision repair (NER) pathway. The xeroderma pigmentosum (XP) complementation group of genes plays an essential role in the NER pathway. We hypothesized that genetic polymorphisms in XP genes may predict clinical response to platinum chemotherapeutic treatment and survival in women with gynecological cancers. METHOD: We genotyped 146 cases of advanced epithelial ovarian cancer for XP gene polymorphisms using the PCR-RFLP method. Kaplan-Meier plots and the log-rank test were used to assess associations between survival and recurrence-free interval and the XP gene polymorphisms. Hazard ratio of response was estimated from an adjusted multivariate Cox proportional hazard model. RESULTS: Women with a heterozygous variant XPA allele had shorter median survival (21.5 months, P=0.03) and shorter median time to recurrence (11.3 months, P=0.05) than women with the homozygous wild-type allele (37.9 and 13.9 months, respectively). Women with a homozygous variant XPG allele had significantly shorter median survival (8.3 months, P=0.006) compared with women with the homozygous XPG wild-type allele (24.6 months). Polymorphisms in XPC, XPD exon10, and XPD exon23 were associated with a decreased risk of recurrence and death, but were not statistically significant. CONCLUSIONS: This study suggests that NER gene polymorphisms may correlate with recurrence and patient survival. A larger sample size is needed to assess platinum chemotherapy response with these polymorphisms. These findings may help identify subgroups of cancer patients likely to benefit from individualized treatment strategies. Our next study will examine NER gene polymorphisms in cervical cancer patients.


Assuntos
Antineoplásicos/farmacologia , Reparo do DNA/genética , Compostos Organoplatínicos/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Alelos , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Proteína de Xeroderma Pigmentoso Grupo A/genética , Proteína Grupo D do Xeroderma Pigmentoso/genética
11.
Gynecol Oncol ; 107(1 Suppl 1): S155-62, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17826825

RESUMO

BACKGROUND: Recent studies have demonstrated that cyclooxygenase-2 (COX-2) expression is up-regulated in a number of cancers. Selective inhibition of COX-2 offers a potential pharmacological strategy for cancer prevention. The COX-2 isoform is induced in response to inflammatory factors and is expressed in premalignant lesions, including cervical tissues. Few studies have investigated COX-2 expression as a biomarker for early cervical carcinogenesis. In this preliminary study, we assessed the variability of COX-2 overexpression in cervical premalignant lesions. METHODS: Fifty-two patients were recruited and consented. Paired abnormal and control (normal) cervical biopsies were obtained and evaluated for high-risk human papillomavirus (HPV), inflammation, histopathological diagnosis, and COX-2 protein concentration by ELISA. Paired Student's t-test and general linear regression models were used to compare mean COX-2 protein concentrations among biopsy samples and selected risk variables. RESULTS: Forty-seven of fifty-two paired biopsies were evaluated. COX-2 protein concentrations were 4.9-fold greater in abnormal biopsies (CIN 1 and CIN 2) than normal biopsies. COX-2 was also significantly increased in inflammation-positive biopsies. No significant association was found between COX-2 levels and HPV high-risk positivity, age, parity, STI history, or hormonal contraceptive use, but the sample size was small. CONCLUSIONS: These results suggest that COX-2 induction begins in the premalignant phase of cervical carcinogenesis and is correlated with inflammation. A trial using a much larger number of specimens will allow further development of our understanding of COX-2 as a biomarker for use in chemoprevention trials.


Assuntos
Biomarcadores Tumorais/biossíntese , Ciclo-Oxigenase 2/biossíntese , Neoplasias do Colo do Útero/enzimologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Células HeLa , Humanos , Inflamação/enzimologia , Inflamação/patologia , Inflamação/virologia , Modelos Lineares , Pessoa de Meia-Idade , Infecções por Papillomavirus/enzimologia , Infecções por Papillomavirus/patologia , Projetos Piloto , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia
12.
Clin Exp Med ; 1(2): 75-80, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11699731

RESUMO

Interferon gamma (IFN-gamma) exerts major pro-inflammatory, regulatory, and anti-inflammatory actions in immune defense responses. In asthma the infiltration of eosinophils, neutrophils, and lymphocytes is a critical event. Chemokines stimulate the migration of the susceptible subset of inflammatory cells. The chemokine receptors CCR-3 are mainly expressed in eosinophils, basophils, and Th2 cells. More recently it has been demonstrated that the IFN-gamma downregulates the expression of some chemokine receptors. IgE determinations were performed using an ELISA for total IgE Peripheral blood leukocytes from patients and controls were isolated by Ficoll-Hypaque gradient. The cells were incubated in the absence or presence of 500 IU/ml of recombinant human IFN-gamma for different times. After incubation the cells were washed and lyzed for reverse transcription-polymerase chain reaction (RT-PCR) analysis. RT-PCR was performed using a Perkin-Elmer kit. The amplified bands were run in 2% agarose gels and quantified. The basal levels of CCR-3 in asthmatic patients with IgE > 150 IU/ml tend to be higher than in controls. IFN-gamma down-regulates the expression of CCR-3 in peripheral blood leukocytes from asthmatics with IgE >150 IU/ml, when compared with the basal levels of expression. In conclusions, through the modification of the expression of CCR-3 in peripheral blood leukocytes from atopic asthmatics, IFN-gamma could exert a beneficial effect in patients with asthma, regulating the migration of some inflammatory cells involved in the pathogenesis of the disease.


Assuntos
Asma/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Interferon gama/farmacologia , Leucócitos/metabolismo , RNA Mensageiro/análise , Receptores de Quimiocinas/genética , Adolescente , Adulto , Asma/tratamento farmacológico , Feminino , Humanos , Interferon gama/uso terapêutico , Masculino , Pessoa de Meia-Idade , Receptores CCR3 , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Dis Colon Rectum ; 40(11): 1362-7, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9369114

RESUMO

UNLABELLED: Fulminant amebic colitis is a rare disease with high morbidity and mortality. PURPOSE: This study was designed to identify the most frequent clinical and histopathologic features of fulminant amebic colitis and to analyze results of surgical treatment and the existence of risk factors for mortality. MATERIALS AND METHODS: A retrospective analysis was conducted of clinical and histopathologic data of 55 patients with fulminant amebic colitis. Data were obtained from the files of autopsies and surgical operations that had been performed at a referral center in Mexico from 1943 through 1994. RESULTS: Median age was 52 (range, 18-79) years. There were 34 men (62 percent) and 21 women (38 percent). Diabetes mellitus and chronic alcoholism were the most frequent diseases in association with fulminant amebic colitis (40 and 31 percent, respectively). The most frequent clinical manifestations were abdominal pain, diarrhea, rectal bleeding, and fever. There was a coexistent amebic liver abscess in 54 percent of patients. The main histopathologic characteristics were necrosis, presence of trophozoites, and acute and/or chronic inflammation. Of 25 patients who underwent surgery, only six survived (operative mortality, 76 percent; overall mortality, 89 percent). The variables that correlated with mortality were longer duration of symptoms, lower count of leukocytes, nonsurgical treatment, nonresective surgical procedure, hospital admission before 1971, and invasion of trophozoites into or through the muscularis. CONCLUSIONS: The results may help to obtain an earlier diagnosis and establish proper treatment of fulminant amebic colitis.


Assuntos
Disenteria Amebiana , Adolescente , Adulto , Idoso , Animais , Disenteria Amebiana/complicações , Disenteria Amebiana/mortalidade , Disenteria Amebiana/patologia , Disenteria Amebiana/cirurgia , Feminino , Humanos , Abscesso Hepático/complicações , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
14.
Development ; 124(14): 2729-39, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9226444

RESUMO

Our previous studies have shown that hindbrain neural tube cells can regulate to form neural crest cells for a limited time after neural fold removal (Scherson, T., Serbedzija, G., Fraser, S. E. and Bronner-Fraser, M. (1993). Development 188, 1049-1061; Sechrist, J., Nieto, M. A., Zamanian, R. T. and Bronner-Fraser, M. (1995). Development 121, 4103-4115). In the present study, we ablated the dorsal hindbrain at later stages to examine possible alterations in migratory behavior and/or gene expression in neural crest populations rostral and caudal to the operated region. The results were compared with those obtained by misdirecting neural crest cells via rhombomere rotation. Following surgical ablation of dorsal r5 and r6 prior to the 10 somite stage, r4 neural crest cells migrate along normal pathways toward the second branchial arch. Similarly, r7 neural crest cells migrate primarily to the fourth branchial arch. When analogous ablations are performed at the 10-12 somite stage, however, a marked increase in the numbers of DiI/Hoxa-3-positive cells from r7 are observed within the third branchial arch. In addition, some DiI-labeled r4 cells migrate into the depleted hindbrain region and the third branchial arch. During their migration, a subset of these r4 cells up-regulate Hoxa-3, a transcript they do not normally express. Krox20 transcript levels were augmented after ablation in a population of neural crest cells migrating from r4, caudal r3 and rostral r3. Long-term survivors of bilateral ablations possess normal neural crest-derived cartilage of the hyoid complex, suggesting that misrouted r4 and r7 cells contribute to cranial derivatives appropriate for their new location. In contrast, misdirecting of the neural crest by rostrocaudal rotation of r4 through r6 results in a reduction of Hoxa-3 expression in the third branchial arch and corresponding deficits in third arch-derived structures of the hyoid apparatus. These results demonstrate that neural crest/tube progenitors in the hindbrain can compensate by altering migratory trajectories and patterns of gene expression when the adjacent neural crest is removed, but fail to compensate appropriately when the existing neural crest is misrouted by neural tube rotation.


Assuntos
Proteínas de Ligação a DNA/genética , Face/embriologia , Genes Homeobox , Proteínas de Homeodomínio/genética , Crista Neural/citologia , Rombencéfalo/embriologia , Crânio/embriologia , Fatores de Transcrição/genética , Fatores Etários , Animais , Movimento Celular , Embrião de Galinha , Proteína 2 de Resposta de Crescimento Precoce , Regulação da Expressão Gênica no Desenvolvimento , Osso Hioide/embriologia , Hibridização In Situ , Morfogênese , Sistema Nervoso/embriologia
15.
J Am Soc Echocardiogr ; 10(3): 210-4, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9109685

RESUMO

A mechanism proposed to contribute to the antianginal effect of nitroglycerin is a redistribution of coronary blood flow to the subendocardium. Contrast echocardiography combines ultrasound with echogenic contrast agents to assess regional myocardial perfusion. This study aims to assess the effect of nitroglycerin on myocardial transmural perfusion with contrast echocardiography in humans. Nine patients scheduled for coronary angiography received 300 microg intracoronary nitroglycerin. Contrast echocardiographic studies were performed before and immediately after the administration of intracoronary nitroglycerin. Videodensitometric analysis was performed off-line to measure subendocardial and subepicardial opacification. Subendocardial opacification greater than subepicardial opacification increased from six of 13 patients before nitroglycerin administration to 11 of 13 after nitroglycerin administration (p <0.05). Similarly, these observations increased from nine of 13 patients to 13 of 13 after nitroglycerin administration during diastole (p <0.05). Contrast echocardiography demonstrates increased subendocardial perfusion after the administration of nitroglycerin in these patients.


Assuntos
Meios de Contraste , Circulação Coronária/efeitos dos fármacos , Ecocardiografia , Iopamidol , Nitroglicerina/farmacologia , Angina Pectoris/diagnóstico por imagem , Angina Pectoris/tratamento farmacológico , Angina Pectoris/fisiopatologia , Pressão Sanguínea/efeitos dos fármacos , Endocárdio/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Development ; 122(3): 895-904, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8631267

RESUMO

We have investigated the pattern and regulation of Hoxa3 expression in the hindbrain and associated neural crest cells in the chick embryo, using whole mount in situ hybridization in conjunction with DiI labeling of neural crest cells and microsurgical manipulations. Hoxa3 is expressed in the neural plate and later in the neural tube with a rostral border of expression corresponding to the boundary between rhombomeres (r) 4 and 5. Initial expression is diffuse and becomes sharp after boundary formation. Hoxa3 exhibits uniform expression within r5 after formation of rhombomeric borders. Cell marking experiments reveal that neural crest cells migrating caudally, but not rostrally, from r5 and caudally from r6 express Hoxa3 in normal embryo. Results from transposition experiments demonstrate that expression of Hoxa3 in r5 neural crest cells is not strictly cell-autonomous. When r5 is transposed with r4 by rostrocaudal rotation of the rhomobomeres, Hoxa3 is expressed in cells migrating lateral to transposed r5 and for a short time, in condensing ganglia, but not by neural crest within the second branchial arch. Since DiI-labeled cells from transposed r5 are present in the second arch, Hoxa3-expressing neural crest cells from r5 appear to down-regulate their Hoxa3 expression in their new environment. In contrast, when r6 is transposed to the position of r4 after boundary formation, Hoxa3 is maintained in both migrating neural crest cells and those positioned within the second branchial arch and associated ganglia. These results suggest that Hoxa3 expression is cell-autonomous in r6 and its associated neural crest. Our results suggest that neural crest cells expressing the same Hox gene are not eqivalent; they respond differently to environmental signals and exhibit distinct degrees of cell autonomy depending upon their rhombomere of origin.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Homeodomínio , Crista Neural/fisiologia , Rombencéfalo/embriologia , Animais , Embrião de Galinha , Indução Embrionária , Regulação da Expressão Gênica no Desenvolvimento , Hibridização In Situ , RNA Mensageiro/genética
17.
Chronobiol Int ; 8(1): 67-74, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1814605

RESUMO

The objective of this study was to determine in mice if a time-dependent pancreatic beta-cell susceptibility to alloxan could be correlated to daily changes in blood glucose levels and to monitor the pattern of blood glucose at various times of day as mice became diabetic. Food was removed from mice standardized to a 12-h light:dark cycle (lights on at 0600 h CST, during the month of June) at 12 h before subcutaneous injection with 0.27 mg/g of alloxan. Six groups of 30 fasted mice were injected at 4-h intervals. Blood glucose levels were measured from each group immediately prior to injection, and at 2, 4, 8, 12, 24, 48, and 216 h after treatment. Animals receiving alloxan during the early- to middark period had an increase in blood glucose after 2 h, followed by a decline to hypoglycemic levels between 4 and 8 h, and recovery to hyperglycemic levels 48 h after alloxan exposure. Three and 30% of these animals were dead at 8 and 48 h, respectively. Mice treated during the midlight span had decreased blood glucose levels 2 h after alloxan treatment followed by an increase to diabetic hyperglycemia within 48 h. Twenty-three and 70% of the animals treated at 1430 h were dead at 8 and 48 h, respectively. At 216 h, total mortality was 45.6% and 81 of the 98 surviving mice were hyperglycemic. These data suggest a greater sensitivity to alloxan during the midlight resting period of the mice. This may be the result of increased sensitivity to the insulin released from the beta cells when alloxan was given during the light span.


Assuntos
Aloxano/toxicidade , Glicemia/metabolismo , Ritmo Circadiano , Aloxano/administração & dosagem , Análise de Variância , Animais , Morte , Esquema de Medicação , Masculino , Camundongos , Camundongos Endogâmicos
18.
Acta Chir Scand Suppl ; 517: 179-203, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6428103

RESUMO

A multicenter clinical study was done which directly compared efficacy and safety of Intralipid 10% and Intralipid 20%. Twenty-nine patients received the 10% concentration, 30 patients received the 20% concentration. Both groups of patients received equivalent amounts of calories, amino acids, dextrose and fat for seven day study periods. Analysis of nitrogen balance data showed that the two preparations were equally effective in maintaining nitrogen balance. Both concentrations of fat emulsion were effective in reversing or correcting the changes of essential fatty acid deficiency. Analysis of clinical laboratory data indicated that both preparations were equally well tolerated by the patients. No adverse effects attributed to the fat emulsions were observed.


Assuntos
Ingestão de Energia , Emulsões Gordurosas Intravenosas/administração & dosagem , Ácidos Graxos Essenciais/administração & dosagem , Adulto , Aminoácidos/administração & dosagem , Coagulação Sanguínea , Glicemia/metabolismo , Peso Corporal , Eletrólitos/sangue , Contagem de Eritrócitos , Emulsões Gordurosas Intravenosas/efeitos adversos , Emulsões Gordurosas Intravenosas/uso terapêutico , Ácidos Graxos/sangue , Feminino , Glucose/administração & dosagem , Hematócrito , Humanos , Lipídeos/sangue , Testes de Função Hepática , Masculino , Nitrogênio/metabolismo , Concentração Osmolar , Nutrição Parenteral Total
19.
Int J Obes ; 5(3): 231-6, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7275460

RESUMO

Obese individuals maintained for 64 days on either of two low-calorie diets (600-800 kcal/day), consisting of protein alone or protein plus carbohydrate, varied widely in the extent of their cumulative nitrogen deficits. Rates of weight loss showed little correlation with rates of nitrogen loss after the first 28 days of the study. The low-calorie diet consisting entirely of protein increased blood beta-hydroxybutyrate concentrations far more than did a diet consisting of equal parts of protein and carbohydrate. The diet which consisted almost entirely of protein did not spare body protein better or induce a greater rate of weight loss than did the mixture of protein and carbohydrate.


Assuntos
Dieta Redutora , Carboidratos da Dieta/farmacologia , Proteínas Alimentares/farmacologia , Obesidade/metabolismo , Ácido 3-Hidroxibutírico , Adulto , Peso Corporal , Humanos , Hidroxibutiratos/sangue , Masculino , Nitrogênio/metabolismo , Obesidade/dietoterapia , Fatores de Tempo , Ácido Úrico/sangue
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