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1.
Reprod Biomed Online ; 17(4): 524-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18854107

RESUMO

Enthusiasm for oocyte cryopreservation has been limited by poor pregnancy rates per thawed metaphase II (MII) oocytes (<4%) and low implantation rates per embryos. The reasons relate to technical limitations in the freezing process, and the fact that <40% of oocytes are euploid and unable to produce 'competent' embryos. Comparative genomic hybridization was performed on the first polar body (PB-1) of 323 MII oocytes retrieved from 16 donors. Of these, 111 were euploid, and were vitrified. Seventy-five of 78 vitrified oocytes (96%) survived warming and were fertilized using intracytoplasmic sperm injection. Thirty-one (41%) subsequently developed into expanded blastocysts, of which no more than two were subsequently transferred per uterus to 16 out of 19 prospective embryo recipients. Twelve of 19 (63%) recipients produced 17 healthy babies (eight singletons, three twins, and one set of triplets) One twin pregnancy miscarried in the late first trimester The birth rate per transfer of a maximum of two blastocysts to 16 recipients was 75%. The implantation rate per vitrified euploid oocyte was 27%. This study showed a six-fold improvement in pregnancy rate per cryopreserved oocyte over previous reports and a marked improvement in implantation rate. If independently validated, this approach could open the door to commercial egg cryobanking, significantly expanding women's reproductive choices.


Assuntos
Criopreservação/métodos , Fertilização/fisiologia , Oócitos , Ploidias , Taxa de Gravidez , Adulto , Sobrevivência Celular , Transferência Embrionária , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Gravidez Múltipla/estatística & dados numéricos , Gêmeos , Adulto Jovem
2.
Oncogene ; 27(4): 557-64, 2008 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-17653092

RESUMO

Recently, we identified a lung adenocarcinoma signature that segregated tumors into three clades distinguished by histological invasiveness. Among the genes differentially expressed was the type II transforming growth factor-beta receptor (TGFbetaRII), which was lower in adenocarcinoma mixed subtype and solid invasive subtype tumors compared with bronchioloalveolar carcinoma. We used a tumor cell invasion system to identify the chemokine CCL5 (RANTES, regulated on activation, normal T-cell expressed and presumably secreted) as a potential downstream mediator of TGF-beta signaling important for lung adenocarcinoma invasion. We specifically hypothesized that RANTES is required for lung cancer invasion and progression in TGFbetaRII-repressed cells. We examined invasion in TGFbetaRII-deficient cells treated with two inhibitors of RANTES activity, Met-RANTES and a CCR5 receptor-blocking antibody. Both treatments blocked invasion induced by TGFbetaRII knockdown. In addition, we examined the clinical relevance of the RANTES-CCR5 pathway by establishing an association of RANTES and CCR5 immunostaining with invasion and outcome in human lung adenocarcinoma specimens. Moderate or high expression of both RANTES and CCR5 was associated with an increased risk for death, P=0.014 and 0.002, respectively. In conclusion, our studies indicate RANTES signaling is required for invasion in TGFbetaRII-deficient cells and suggest a role for CCR5 inhibition in lung adenocarcinoma prevention and treatment.


Assuntos
Adenocarcinoma/patologia , Quimiocina CCL5/fisiologia , Neoplasias Pulmonares/patologia , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Quimiocina CCL5/genética , Quimiocina CCL5/metabolismo , Estudos de Coortes , Fibroblastos/metabolismo , Fibroblastos/patologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Invasividade Neoplásica , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores CCR5/genética , Receptores CCR5/metabolismo , Células Estromais/metabolismo , Células Estromais/patologia , Análise de Sobrevida , Células Tumorais Cultivadas
3.
Reprod Biomed Online ; 14(1): 9-10, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17207322

RESUMO

HLA-G is believed to play a pivotal role in the immunoprotection of the semiallogenic embryo. Its expression during pre- and early implantation is correlated with the cleavage rate of the embryo. Studies in congenic mice have revealed that mRNA of both the maternal and paternal haplotypes are present in zygotes and in embryos at all stages of development.


Assuntos
Embrião de Mamíferos/imunologia , Antígenos HLA/biossíntese , Antígenos de Histocompatibilidade Classe I/biossíntese , Adulto , Animais , Embrião de Mamíferos/metabolismo , Feminino , Antígenos HLA/genética , Antígenos HLA-G , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Camundongos , Gravidez , Taxa de Gravidez , RNA Mensageiro/metabolismo
4.
Hum Reprod ; 20(5): 1359-63, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15746200

RESUMO

BACKGROUND: We have previously reported the retrospective observation that when at least one embryo, transferred on day 3, expressed sHLA-G above the geometric mean (sHLA-G+) 46 h post-ICSI, there was a marked improvement in both pregnancy (PR) and implantation (IR) rates. METHODS: The media surrounding individual embryos derived from ICSI performed on oocytes from 482 women < or =43 years of age were tested for sHLA-G expression by specific ELISA. RESULTS: We report here prospective results showing improved IVF results following the transfer of 'good quality' embryos (7-9 cells with <20% fragmentation) by preferentially including at least one sHLA-G+ embryos. PR and IR for women < or =38 years were 63% and 32% when one transferred embryo was sHLA-G+, and 69% and 36% when at least two embryos were sHLA-G+. When none of the embryos transferred was sHLA-G+, PR and IR were 25% and 13%, respectively. Comparable PR and IR for women 39-43 years were 29% and 11% when none of the transferred embryos were sHLA-G+; 38% and 15% when at least one sHLA-G+ embryo was transferred; and 61% and 26% when at least two 2 sHLA-G+ embryos were transferred. The data were stratified by patient age. CONCLUSIONS: PR and IR increased with the addition of each sHLA-G+ embryo, regardless of age. While there are significant barriers to routine embryo sHLA-G testing, we believe that if implemented, this would provide a mechanism for optimizing IVF PR while minimizing the risk of multiple pregnancies.


Assuntos
Implantação do Embrião/fisiologia , Antígenos HLA/genética , Antígenos de Histocompatibilidade Classe I/genética , Taxa de Gravidez , Injeções de Esperma Intracitoplásmicas , Adulto , Blastocisto/imunologia , Transferência Embrionária , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Antígenos HLA-G , Humanos , Masculino , Idade Materna , Gravidez , Estudos Prospectivos
5.
Cell Biol Int ; 25(12): 1229-36, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11748916

RESUMO

Non-mammalian vertebrate erythrocytes are flattened nucleated ellipsoids containing marginal bands (MBs) of microtubules that assemble during cellular morphogenesis. Earlier work suggested that pointed erythroid cells containing pointed MBs were intermediate stages in terminal differentiation, rather than aberrant forms, but direct evidence was lacking. Here we report on morphogenesis in individual post-cytokinetic amphibian erythroblasts in culture. Daughter cells remained adjacent in pairs, and developed pointed morphology over 1-2 h in the following sequence: (a) ends opposite the cytokinetic furrow became pointed, producing a spheroidal singly-pointed stage; (b) furrow ends usually became pointed, yielding doubly-pointed cells; (c) furrow-end points disappeared, producing a second singly-pointed stage that was flattening. Over a longer term, the single points sometimes disappeared, yielding a flattened discoid. These observations support the hypothesis that pointed cells are normal intermediates in a biogenetic program in which post-mitotic centrosomes organize MBs while occupying the singly-pointed ends of differentiating erythroblasts.


Assuntos
Ambystoma/embriologia , Eritroblastos/citologia , Animais , Técnicas In Vitro , Larva , Microscopia de Contraste de Fase , Morfogênese , Baço/citologia , Baço/ultraestrutura
6.
Am J Respir Crit Care Med ; 163(3 Pt 1): 786-91, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11254539

RESUMO

Pulmonary emphysema is believed to result from an imbalance between proteolytic enzymes and their inhibitors. Multiple studies have examined the presence of various proteases within the bronchoalveolar lavage fluid from patients with chronic obstructive pulmonary disease (COPD). However, to date extensive examination of the lung parenchyma for the expression of destructive enzymes has not yet been determined. The following study examines the lung parenchyma of 23 patients with emphysema and 8 normal control samples for the expression of matrix matalloproteinase-1 (MMP-1), MMP-12, and MMP-9. We report here that interstitial collagenase (MMP-1) RNA, protein, and activity are present in the lung parenchyma of patients with emphysema and not in the lung of normal control subjects. In contrast, metalloelastase (MMP-12) expression is absent in these samples. Immunohistochemistry studies localized MMP-1 to the Type II pneumocyte in patients with emphysema and not normal control subjects or smokers without emphysema. This observation demonstrates that the lung is altered in emphysema such that the Type II pneumocyte secretes MMP-1 and suggests that MMP-1 may be an important enzyme involved in the destruction of the lung in the human disease. In addition, the induction of a proteolytic enzyme within the Type II pneumocyte suggests that the cells within the lung itself are capable of producing degradative enzymes in this disease process.


Assuntos
Enfisema/enzimologia , Pulmão/enzimologia , Metaloproteinase 1 da Matriz/biossíntese , Adulto , Idoso , Feminino , Humanos , Masculino , Metaloproteinase 1 da Matriz/genética , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , Inibidores Teciduais de Metaloproteinases/biossíntese
7.
Ann Thorac Surg ; 71(1): 364-6, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11216787

RESUMO

Pneumonectomy is rarely required in the surgical management of thoracic traumatic injuries with high mortality rates. Right heart failure due to elevated pulmonary artery pressure and the adult respiratory distress syndrome have been leading causes of mortality reported after posttraumatic pneumonectomy. The beneficial effect of inhaled nitric oxide has been shown in pulmonary hypertension and in adult respiratory distress syndrome. We report the use of inhaled nitric oxide in the perioperative management of a patient undergoing emergent pneumonectomy.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Óxido Nítrico/uso terapêutico , Pneumonectomia , Vasodilatadores/uso terapêutico , Ferimentos por Arma de Fogo/cirurgia , Administração por Inalação , Adulto , Humanos , Masculino , Óxido Nítrico/administração & dosagem , Artéria Pulmonar/lesões , Vasodilatadores/administração & dosagem
8.
West J Med ; 173(6): 390-4, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11112752

RESUMO

OBJECTIVE: To identify physicians' views regarding cost-containment and cost-effectiveness and their attitudes and experience using cost-effectiveness in clinical decision making. DESIGN: A close-ended 30-item written survey. SUBJECTS: 1,000 randomly selected physicians whose practices currently encompass direct patient care and who work in the California counties of Sacramento, Yolo, Placer, Nevada, and El Dorado. OUTCOME MEASURES: Physician attitudes about the role of cost and cost-effectiveness in treatment decisions, perceived barriers to cost-effective medical practice, and response of physicians and patients if there are conflicts about treatment that physicians consider either not indicated or not cost-effective. RESULTS: Most physicians regard cost-effectiveness as an appropriate component of clinical decisions and think that only the treating physician and patient should decide what is cost-worthy. However, physicians are divided on whether they have a duty to offer medical interventions with remote chances of benefit regardless of cost, and they vary considerably in their interactions with patients when cost-effectiveness is an issue. CONCLUSION: Although physicians in the Sacramento region accept cost-effectiveness as important and appropriate in clinical practice, there is little uniformity in how cost-effectiveness decisions are implemented.


Assuntos
Atitude do Pessoal de Saúde , Assistência ao Paciente/economia , Médicos/psicologia , Padrões de Prática Médica/economia , California , Análise Custo-Benefício/estatística & dados numéricos , Tomada de Decisões , Humanos , Assistência ao Paciente/estatística & dados numéricos , Relações Médico-Paciente , Médicos/economia , Médicos/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Inquéritos e Questionários
9.
Am J Pathol ; 157(4): 1311-20, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11021835

RESUMO

The transcription factor early growth response (Egr)-1 is an immediate-early gene product rapidly and transiently expressed after acute tissue injury. In contrast, in this report we demonstrate that lung tissue from patients undergoing lung reduction surgery for advanced emphysema, without clinical or anatomical evidence of acute infection, displays a selective and apparently sustained increase in Egr-1 transcripts and antigen, compared with a broad survey of other genes, including the transcription factor Sp1, whose levels were not significantly altered. Enhanced Egr-1 expression was especially evident in smooth muscle cells of bronchial and vascular walls, in alveolar macrophages, and some vascular endothelium. Gel shift analysis with (32)P-labeled Egr probe showed a band with nuclear extracts from emphysematous lung which was supershifted with antibody to Egr-1. Egr-1 has the capacity to regulate genes relevant to the pathophysiology of emphysema, namely those related to extracellular matrix formation and remodeling, thrombogenesis, and those encoding cytokines/chemokines and growth factors. Thus, we propose that further analysis of Egr-1, which appears to be up-regulated in a sustained fashion in patients with late stage emphysema, may provide insights into the pathogenesis of this destructive pulmonary disease, as well as a new facet in the biology of Egr-1.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Enfisema/metabolismo , Proteínas Imediatamente Precoces , Fatores de Transcrição/metabolismo , Idoso , Northern Blotting , Células Cultivadas , DNA Complementar/metabolismo , Proteínas de Ligação a DNA/genética , Progressão da Doença , Proteína 1 de Resposta de Crescimento Precoce , Enfisema/genética , Enfisema/patologia , Humanos , Pulmão/metabolismo , Pulmão/patologia , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Fatores de Transcrição/genética
11.
J Appl Physiol (1985) ; 87(3): 1213-9, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10484598

RESUMO

The purpose of this investigation was to determine whether there were differences in the magnitude of insular cortex activation across varying intensities of static and dynamic exercise. Eighteen healthy volunteers were studied: eight during two intensities of leg cycling and ten at different time periods during sustained static handgrip at 25% maximal voluntary contraction or postexercise cuff occlusion. Heart rate, blood pressure (BP), perceived exertion, and regional cerebral blood flow (rCBF) distribution data were collected. There were significantly greater increases in insular rCBF during lower (6.3 +/- 1.7%; P < 0.05) and higher (13.3 +/- 3.8%; P < 0.05) intensity cycling and across time during static handgrip (change from rest for right insula at 2-3 min, 3.8 +/- 1.1%, P < 0.05; and at 4-5 min, 8.6 +/- 2.8%, P < 0.05). Insular rCBF was decreased during postexercise cuff occlusion (-5.5 +/- 1.2%; P < 0.05) with BP sustained at exercise levels. Right insular rCBF data, but not left, were significantly related, with individual BP changes (r(2) = 0.80; P < 0.001) and with ratings of perceived exertion (r(2) = 0.79; P < 0.01) during exercise. These results suggest that the magnitude of insular activation varies with the intensity of exercise, which may be further related to the level of perceived effort or central command.


Assuntos
Córtex Cerebral/fisiologia , Exercício Físico/fisiologia , Adulto , Ciclismo/fisiologia , Pressão Sanguínea/fisiologia , Córtex Cerebral/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Feminino , Força da Mão/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Tomografia Computadorizada de Emissão de Fóton Único
13.
Am J Respir Crit Care Med ; 157(5 Pt 1): 1593-9, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9603143

RESUMO

The volume and severity of pulmonary emphysema in individual lungs were measured by means of quantitative computed tomography (CT) studies in 28 patients (14 women, 14 men, median age 65 yr) who underwent either bilateral (n = 15) or unilateral (n = 13) lung volume reduction surgery (LVRS). Spirometric, total body plethysmographic, and CT data (at TLC and RV) were correlated before and after LVRS. Lung volumes determined by CT correlated well with volumes obtained by total body plethysmography (p < 0.0001). For individual lungs after LVRS, CT-derived mean lung capacity decreased 13% and residual volume 20% (p < 0.00001 for each), while mean total functional lung volume (TFLV, defined as the volume of lung with CT attenuation greater than -910 Hounsfield units) increased 9% (p < 0.01), and the mean ratio of the air space to tissue space volume (V(AS)/V(TS)) decreased more at RV (23%) than at TLC (14%) (p < 0.0005 for each). In contrast, unilateral LVRS did not affect exhalation from the unoperated lung (2% reduction in RV, p = NS). The magnitude of the postoperative response (CT-derived TLC, RV, TFLV, V(AS)/V(TS)) of each operated lung was comparable for unilateral and bilateral LVRS. Thus, a lung's response to LVRS was independent from that of the contralateral lung. Moreover, postoperative alterations in TFLV and FEV1 correlated significantly (r = 0.80, p < 0.0001), which suggests that the expansion of functioning tissue may contribute to the mechanism by which LVRS palliates airway obstruction.


Assuntos
Medidas de Volume Pulmonar , Pulmão/diagnóstico por imagem , Pulmão/cirurgia , Enfisema Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pletismografia Total , Enfisema Pulmonar/fisiopatologia , Enfisema Pulmonar/cirurgia , Volume Residual , Espirometria , Capacidade Pulmonar Total
14.
Ann Thorac Surg ; 65(2): 314-8, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9485220

RESUMO

BACKGROUND: Severe pulmonary dysfunction has been considered a relative contraindication to surgical resection in patients with solitary pulmonary nodules. We report our initial experience with the combined use of lung volume reduction operation and tumor resection in this patient population. METHODS AND PATIENTS: Between January 1995 and July 1996, 14 patients underwent combined lung volume reduction operation and pulmonary nodule resection. Ten (71%) patients were oxygen dependent, 5 (36%) had a room air partial pressure of carbon dioxide > or = 45, and 5 (36%) were steroid dependent preoperatively. Mean preoperative pulmonary function tests included a forced expiratory volume in 1 second of 680 +/- 98 mL (24% +/- 5% predicted), forced vital capacity of 54% +/- 5% predicted, and a forced expiratory volume in 1 second to vital capacity ratio of 37% +/- 2% predicted. RESULTS: Sixteen lesions were resected in the 14 patients and included 9 non-small cell carcinomas. There was one postoperative death. All other patients are alive and well through a mean follow-up of 22.6 +/- 2.3 months (12 to 35 months). At 6-month follow-up improvements were noted in dyspnea index, forced expiratory volume in 1 second forced vital capacity, and 6-minute walk distance. Mediastinal recurrence at 12-month follow-up developed in 1 patient with two separate bronchioalveolar carcinomas. CONCLUSIONS: Simultaneous lung volume reduction operation and tumor resection should be considered in patients with emphysema with marginal reserve in the hope of maximizing postoperative lung function.


Assuntos
Neoplasias Pulmonares/cirurgia , Pulmão/cirurgia , Enfisema Pulmonar/cirurgia , Nódulo Pulmonar Solitário/cirurgia , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/complicações , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Feminino , Seguimentos , Volume Expiratório Forçado , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Enfisema Pulmonar/complicações , Enfisema Pulmonar/fisiopatologia , Nódulo Pulmonar Solitário/complicações , Nódulo Pulmonar Solitário/fisiopatologia , Capacidade Vital
15.
Neurosurgery ; 42(1): 56-62; discussion 62-5, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9442504

RESUMO

OBJECTIVE: The optimal choice of imaging and localization for stereotactic surgery for movement disorders remains uncertain, with controversy surrounding the use of microelectrode recording and the role of distortion of magnetic resonance imaging (MRI) scans in reducing the accuracy of lesion placement. We review our experience with 67 pallidotomies and 35 thalamotomies performed without microelectrode recording, using instead individual variations in anatomic landmarks. METHODS: Computed tomography is used as the primary modality, with comparison with carefully angled MRI scans and the use of neural structures, such as the mamillary bodies and the vascular anatomy. Pallidal target sites are chosen immediately lateral and superior to the optic tract on a line bisecting the axis of the peduncle, with macrostimulation guiding the final adjustment of target position. Forty-seven patients undergoing unilateral pallidotomies were studied in the "off" state and the "on" state using a modified Unified Rating Scale for Parkinson's disease (URSP) score and a dyskinesia scale, preoperatively and postoperatively at 2 weeks, 2 months, 6 months, and 12 months. In the 31 patients undergoing thalamotomy, tremor was rated preoperatively and postoperatively as near-complete resolution, partial resolution, and failure. RESULTS: The "off" state Unified Rating Scale for Parkinson's disease motor score declined from 42.0 to 32.2 at 2 weeks after surgery (P < 0.0001, n = 42). The Unified Rating Scale for Parkinson's disease motor score was 34.2 at 2 months (P < 0.0001, n = 35), 29.4 at 6 months (P < 0.0001, n = 27), and 24.9 at 12 months (P = 0.005, n = 12), representing an overall improvement in "off" state motor function of approximately 25 to 40%. The "on" state dyskinesia score fell from 5.5 to 2.0 at 2 weeks (P < 0.0001) and persisted in the later visits. The dyskinesia score for the contralateral side fell from 2.5 preoperatively to 0.26 at 2 weeks, 0.28 at 2 months, 0.22 at 6 months, and 0.0 at 12 months. Of the patients undergoing thalamotomies, 65% experienced near-complete or complete tremor resolution, 23% experienced partial tremor relief, and 13% were considered treatment failures. CONCLUSION: Stereotactic procedures for movement disorders requiring high precision can be safely and successfully performed without the use of microelectrode recording techniques. Meticulous alignment of MRI and computed tomographic scans based on visualized anatomy allows precise lesion placement and avoids the distortion inherent in MRI scans.


Assuntos
Globo Pálido/cirurgia , Imageamento por Ressonância Magnética , Doença de Parkinson/cirurgia , Técnicas Estereotáxicas , Tálamo/cirurgia , Tomografia Computadorizada por Raios X , Humanos , Doença de Parkinson/diagnóstico , Doença de Parkinson/fisiopatologia , Resultado do Tratamento
16.
Poult Sci ; 76(8): 1084-92, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9251133

RESUMO

The origin of the germ cell lineage in vertebrates is a fundamental question that has preoccupied developmental biologists. Recent work on the origin of the avian germ line has extended and clarified our understanding of the temporal and spatial segregation of primordial germ cells (PGC) during prestreak stages of development. The germ cells first appear at Stage X (Eyal-Giladi and Kochav, 1976) in the ventral surface of the area pellucida in a scattered pattern among polyingressing cells. Subsequently, the PGC gradually translocate from the epiblast to the hypoblast. The entire process appears to be dependent upon the maintenance of an organized area pellucida. Little is known about the regulatory events governing germ cell emergence during this period; however, the culture of dispersed blastodermal cells on a mouse fibroblast feeder layer can compensate for a disorganized area pellucida and offers an in vitro system to examine the molecular basis of germ cell development. Such basic information is valuable for current approaches towards the production of transgenic poultry with targeted changes to the genome through the use of avian embryonic stem cells or primordial germ cells. Refinement of the culture of primordial germ cells or their precursors should allow academic and industrial research laboratories to answer significant biological questions and to improve the genetic potential of commercial poultry stocks. A better understanding of the biology of avian primordial germ cells during early embryo development can only enhance this process.


Assuntos
Animais Geneticamente Modificados , Embrião de Galinha/citologia , Galinhas/genética , Células Germinativas/citologia , Células-Tronco/citologia , Animais , Blastoderma/citologia , Blastoderma/fisiologia , Diferenciação Celular/fisiologia , Células Cultivadas , Embrião de Galinha/crescimento & desenvolvimento , Embrião de Galinha/fisiologia , Feminino , Células Germinativas/fisiologia , Masculino , Camundongos , Células-Tronco/fisiologia
17.
Ann Thorac Surg ; 64(2): 321-6; discussion 326-7, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9262568

RESUMO

BACKGROUND: Lung volume reduction surgery (LVRS) has shown early promise as a palliative therapy in severe emphysema. A number of patients, however, are not candidates for a bilateral operation, or exhibit a predominantly unilateral disease distribution. METHODS: Over 20 months, we performed LVRS in 92 patients selected on the basis of severe hyperinflation with air trapping, diaphragmatic dysfunction, and disease heterogeneity. Twenty-eight patients underwent unilateral LVRS on the basis of asymmetric disease distribution, prior thoracic operation, or concomitant tumor resection. RESULTS: Unilateral LVRS resulted in comparable improvements in exercise capacity and dyspnea as the bilateral procedure, with a similar perioperative mortality and actuarial survival to 24 months. Improvements in spirometric indices of pulmonary function, however, were less in patients undergoing unilateral than bilateral LVRS. CONCLUSIONS: In properly selected patients, unilateral LVRS provides functional and subjective benefits of comparable magnitude to those associated with a bilateral operation. Unilateral LVRS is therefore an option in the therapy of end-stage emphysema in patients with asymmetric disease distribution, a prior thoracic operation, or contraindications to sternotomy, and may have a role as a bridge to transplantation in selected cases.


Assuntos
Pneumonectomia/métodos , Enfisema Pulmonar/cirurgia , Idoso , Idoso de 80 Anos ou mais , Tolerância ao Exercício , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Enfisema Pulmonar/fisiopatologia , Capacidade Vital
19.
Poult Sci ; 76(1): 91-5, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9037694

RESUMO

The origin of the germline is studied in avians by tracing primordial germ cells from the stage of the germinal crescent backwards to earlier developmental stages. It has been demonstrated that during primitive streak formation, the germline has already been segregated. However, during this stage, the cells are seen gradually migrating from the epiblast to the hypoblast. The vertical migration is followed by a horizontal translocation to the extra-embryonic germinal crescent, being carried out by the hypoblast that is pushed anteriorly by the invading endodermal cells. In contrast, it has been shown that in the mouse the germ cells are allocated during gastrulation in a cluster of cells. Our results demonstrate that in avians the allocation takes place according to a different mode. The close association between the germ cells and the extra-embryonic mesoderm indicates that the germline in avians, as in the mouse, develops from a subset of cells that have already segregated from the epiblast as extra-embryonic mesoderm.


Assuntos
Aves/embriologia , Gástrula/citologia , Células Germinativas/citologia , Animais , Diferenciação Celular/fisiologia , Movimento Celular/fisiologia , Endoderma/citologia , Endoderma/fisiologia , Feminino , Gástrula/fisiologia , Células Germinativas/fisiologia , Masculino , Mesoderma/citologia , Mesoderma/fisiologia , Ovário/citologia , Ovário/embriologia , Testículo/citologia , Testículo/embriologia
20.
Ann Thorac Surg ; 62(6): 1588-97, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8957356

RESUMO

BACKGROUND: Lung volume reduction surgery has shown early promise as a palliative therapy in severe emphysema. Selection of potential candidates has been based on certain functional and anatomic criteria, and a variety of operative contraindications have been proposed. METHODS: Over 15 months, we performed lung volume reduction surgery in 85 patients selected on the basis of severe hyperinflation with air trapping, diaphragmatic dysfunction, and disease heterogeneity. Patients were not excluded on the basis of severe hypercapnia, steroid dependence, profound pulmonary dysfunction, or inability to complete preoperative rehabilitation. RESULTS: We observed significant improvements in pulmonary function, exercise capacity, and dyspnea, with an acceptable 30-day perioperative mortality of 7% and actuarial survival of 90% and 83% at 6 and 12 months, respectively. In each "high-risk" group, perioperative mortality, actuarial survival to 1 year, and functional results were equivalent, and in some cases superior, to those in the corresponding "low-risk" patients. CONCLUSIONS: Severe hypercapnia, steroid dependence, profound pulmonary dysfunction, and inability to complete preoperative rehabilitation do not preclude successful lung volume reduction surgery and should not be regarded as absolute exclusionary criteria.


Assuntos
Pulmão/cirurgia , Enfisema Pulmonar/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Volume Expiratório Forçado , Humanos , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Enfisema Pulmonar/mortalidade , Enfisema Pulmonar/fisiopatologia , Taxa de Sobrevida , Capacidade Vital
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