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1.
Clin Radiol ; 75(1): 77.e15-77.e22, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31668796

RESUMO

AIM: To evaluate the microstructural abnormalities of the white matter tracts (WMT) using diffusion tensor imaging (DTI) in children with global developmental delay (GDD). MATERIALS AND METHODS: Sixteen children with GDD underwent magnetic resonance imaging (MRI) and cross-sectional DTI. Formal developmental assessment of all GDD patients was performed using the Mullen Scales of Early Learning. An automated processing pipeline for the WMT assessment was implemented. The DTI-derived metrics of the children with GDD were compared to healthy children with normal development (ND). RESULTS: Only two out of the 17 WMT demonstrated significant differences (p<0.05) in DTI parameters between the GDD and ND group. In the uncinate fasciculus (UF), the GDD group had lower mean values for fractional anisotropy (FA; 0.40 versus 0.44), higher values for mean diffusivity (0.96 versus 0.91×10-3 mm2/s) and radial diffusivity (0.75 versus 0.68×10-3 mm2/s) compared to the ND group. In the superior cerebellar peduncle (SCP), mean FA values were lower for the GDD group (0.38 versus 0.40). Normal myelination pattern of DTI parameters was deviated against age for GDD group for UF and SCP. CONCLUSION: The UF and SCP WMT showed microstructural changes suggestive of compromised white matter maturation in children with GDD. The DTI metrics have potential as imaging markers for inadequate white matter maturation in GDD children.


Assuntos
Cerebelo/anormalidades , Cerebelo/diagnóstico por imagem , Deficiências do Desenvolvimento/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Córtex Pré-Frontal/anormalidades , Córtex Pré-Frontal/diagnóstico por imagem , Substância Branca/anormalidades , Substância Branca/diagnóstico por imagem , Anisotropia , Pré-Escolar , Estudos Transversais , Imagem de Difusão por Ressonância Magnética , Estudos de Viabilidade , Feminino , Humanos , Lactente , Masculino
3.
Clin Radiol ; 71(2): 170-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26688549

RESUMO

AIM: To determine whether lesion size affects the diagnostic performance of apparent diffusion coefficient (ADC) in the evaluation of breast masses. MATERIALS AND METHODS: Consecutive breast lesions detected at magnetic resonance imaging (MRI) from June 2010 to July 2013 were retrospectively reviewed. Differences in the ADCs of benign and malignant mass lesions were compared. Receiver operating characteristics analysis was performed to evaluate diagnostic performance of ADC regarding lesion size (≤ 1 cm or >1 cm) and their T2W signal intensities. RESULTS: Seventy-four malignant lesions (77.9%) and 21 (22.1%) benign lesions were included. Twenty-two of the 95 (23.2%) masses measured ≤ 1 cm (mean 0.73 ± 0.4; range 0.51-0.8 cm) and 73/95 (76.9%) masses measured >1 cm (mean 2.11 ± 0.1; range 1.1-3.3 cm). The mean ADC was significantly lower for malignant than for benign lesions (mean for malignant lesion, 0.89 ± 0.29 × 10(-3) mm(2)/s; mean for benign lesions, 1.27 ± 0.42 × 10(-3) mm(2)/s; p<0.01). The optimal ADC cut-off for differentiating benign and malignant lesion was 1.088 × 10(-3) mm(2)/s with a sensitivity of 85.9% and specificity of 77% for lesions >1 cm. The sensitivity and specificity were lowered to 60% and 50%, respectively, for lesions of size ≤ 1. Maximal sensitivity and specificity were reached when the ADC value was used to evaluate T2-dark lesions. CONCLUSION: Diffusion-weighted MRI is useful for characterizing masses that are hypointense on T2-weighted images. Lower sensitivity and specificity were found for breast lesions ≤ 1 cm.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Imagem de Difusão por Ressonância Magnética , Adulto , Idoso , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Aumento da Imagem , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
4.
Haemophilia ; 19(4): 583-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23560720

RESUMO

The risk of bleeding in patients with hereditary bleeding disorders (HBD) undergoing gastro-intestinal (GI) endoscopic procedures is unknown but guidelines generally recommend correction of factor deficiency. Investigate the safety of oral tranexamic acid (TA) without prophylactic factor replacement to prevent bleeding complications in patients with HBD undergoing elective GI endoscopic procedures. A prospective single-arm pilot study testing the feasibility of using TA, without prophylactic factor replacement or desmopressin preprocedure, for prevention of bleeding complications following elective standard risk (<1% risk of bleeding) endoscopic procedures in patients with HBD. Baseline factor levels, haemoglobin and iron studies (IS) were measured preprocedure. Primary outcome of bleeding (NCI CTCAE v3.0 Bleeding Scale) was undertaken by patient review and repeat Hb, IS on day 21. Twenty-eight patients underwent 32 GI endoscopic procedures from September 2010 until June 2012. The median age was 53 years (range 24-75 years) and disease types included mild haemophilia A/B (n = 12), severe haemophilia A/B (n = 9), von Willebrand disease (n = 5), FXI deficiency (n = 1) and FVII deficiency (n = 1). Procedures performed included 11 gastroscopies, 12 colonoscopies, 8 gastroscopies and colonoscopies and 1 flexible sigmoidoscopy. Fourteen standard risk procedures and two high risk procedures were performed. Two patients experienced Grade 1 bleeding and one patient experienced Grade 2 bleeding. This study suggests that TA without prophylactic factor replacement may be a safe approach for mild and moderate HBD patients undergoing standard risk endoscopic procedures, particularly where no biopsy is performed. These findings should be confirmed in a larger study.


Assuntos
Fatores de Coagulação Sanguínea/uso terapêutico , Endoscopia/efeitos adversos , Hemorragia/tratamento farmacológico , Hemorragia/etiologia , Transtornos Hemorrágicos/tratamento farmacológico , Transtornos Hemorrágicos/prevenção & controle , Ácido Tranexâmico/uso terapêutico , Adulto , Idoso , Biópsia , Perda Sanguínea Cirúrgica/prevenção & controle , Demografia , Feminino , Hemorragia/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Fatores de Risco
5.
Nat Genet ; 20(2): 171-4, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9771710

RESUMO

Lafora's disease (LD; OMIM 254780) is an autosomal recessive form of progressive myoclonus epilepsy characterized by seizures and cumulative neurological deterioration. Onset occurs during late childhood and usually results in death within ten years of the first symptoms. With few exceptions, patients follow a homogeneous clinical course despite the existence of genetic heterogeneity. Biopsy of various tissues, including brain, revealed characteristic polyglucosan inclusions called Lafora bodies, which suggested LD might be a generalized storage disease. Using a positional cloning approach, we have identified at chromosome 6q24 a novel gene, EPM2A, that encodes a protein with consensus amino acid sequence indicative of a protein tyrosine phosphatase (PTP). mRNA transcripts representing alternatively spliced forms of EPM2A were found in every tissue examined, including brain. Six distinct DNA sequence variations in EPM2A in nine families, and one homozygous microdeletion in another family, have been found to cosegregate with LD. These mutations are predicted to cause deleterious effects in the putative protein product, named laforin, resulting in LD.


Assuntos
Cromossomos Humanos Par 6 , Epilepsias Mioclônicas/genética , Mutação , Proteínas Tirosina Fosfatases/genética , Processamento Alternativo , Sequência de Aminoácidos , Sequência de Bases , Mapeamento Cromossômico , Sequência Consenso , Epilepsias Mioclônicas/enzimologia , Feminino , Ligação Genética , Genótipo , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Proteínas Tirosina Fosfatases não Receptoras , RNA Mensageiro/metabolismo
6.
J Cell Biochem ; 113(2): 658-68, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21976004

RESUMO

Bone marrow mesenchymal stromal cells (BMMSCs) have been used as feeder support for the ex vivo expansion of hematopoietic stem cells (HSCs) but have the limitations of painful harvest, morbidity, and risk of infection to the patient. This prompted us to explore the use of human umbilical cord Wharton's jelly MSCs (hWJSCs) and its conditioned medium (hWJSC-CM) for ex vivo expansion of HSCs in allogeneic and autologous settings because hWJSCs can be harvested in abundance painlessly, are proliferative, hypoimmunogenic, and secrete a variety of unique proteins. In the presence of hWJSCs and hWJSC-CM, HSCs put out pseudopodia-like outgrowths and became highly motile. Time lapse imaging showed that the outgrowths helped them to migrate towards and attach to the upper surfaces of hWJSCs and undergo proliferation. After 9 days of culture in the presence of hWJSCs and hWJSC-CM, MTT, and Trypan blue assays showed significant increases in HSC numbers, and FACS analysis generated significantly greater numbers of CD34(+) cells compared to controls. hWJSC-CM produced the highest number of colonies (CFU assay) and all six classifications of colony morphology typical of hematopoiesis were observed. Proteomic analysis of hWJSC-CM showed significantly greater levels of interleukins (IL-1a, IL-6, IL-7, and IL-8), SCF, HGF, and ICAM-1 compared to controls suggesting that they may be involved in the HSC multiplication. We propose that cord blood banks freeze autologous hWJSCs and umbilical cord blood (UCB) from the same umbilical cord at the same time for the patient for future ex vivo HSC expansion and cell-based therapies.


Assuntos
Células-Tronco Hematopoéticas/citologia , Células-Tronco Mesenquimais/metabolismo , Cordão Umbilical/citologia , Geleia de Wharton/citologia , Movimento Celular , Proliferação de Células , Forma Celular , Células Cultivadas , Técnicas de Cocultura , Ensaio de Unidades Formadoras de Colônias , Meios de Cultivo Condicionados/química , Citocinas/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Pseudópodes , Imagem com Lapso de Tempo
7.
J Nanosci Nanotechnol ; 8(7): 3652-60, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19051923

RESUMO

A brief comparison of conventional electronics and spintronics is given. The key features of half metallic binary compounds with the zincblende structure are presented, using MnAs as an example. We discuss the interactions responsible for the half metallic properties. Special properties of superlattices and a digital ferromagnetic heterostructure incorporating zincblende half metals are also discussed.

8.
Nat Biotechnol ; 18(4): 399-404, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10748519

RESUMO

We describe the derivation of pluripotent embryonic stem (ES) cells from human blastocysts. Two diploid ES cell lines have been cultivated in vitro for extended periods while maintaining expression of markers characteristic of pluripotent primate cells. Human ES cells express the transcription factor Oct-4, essential for development of pluripotential cells in the mouse. When grafted into SCID mice, both lines give rise to teratomas containing derivatives of all three embryonic germ layers. Both cell lines differentiate in vitro into extraembryonic and somatic cell lineages. Neural progenitor cells may be isolated from differentiating ES cell cultures and induced to form mature neurons. Embryonic stem cells provide a model to study early human embryology, an investigational tool for discovery of novel growth factors and medicines, and a potential source of cells for use in transplantation therapy.


Assuntos
Blastocisto/citologia , Diferenciação Celular , Células-Tronco/citologia , Animais , Técnicas de Cultura de Células/métodos , Linhagem Celular , Transplante de Células , Proteínas de Ligação a DNA/genética , Marcadores Genéticos , Humanos , Masculino , Camundongos , Camundongos SCID , Fator 3 de Transcrição de Octâmero , Primatas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células-Tronco/patologia , Teratoma/genética , Teratoma/patologia , Neoplasias Testiculares/genética , Neoplasias Testiculares/patologia , Testículo/patologia , Fatores de Transcrição/genética , Transplante Heterólogo
9.
J Bone Joint Surg Br ; 88(5): 586-91, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16645102

RESUMO

Failure of total hip arthroplasty with acetabular deficiency occurred in 55 patients (60 hips) and was treated with acetabular revision using morsellised allograft and a cemented metal-backed component. A total of 50 patients (55 hips) were available for clinical and radiological evaluation at a mean follow-up of 5.8 years (3 to 9.5). No hip required further revision of the acetabular component because of aseptic loosening. All the hips except one had complete incorporation of the allograft demonstrated on the radiographs. A complete radiolucent line of > 1 mm was noted in two hips post-operatively. A good to excellent result occurred in 50 hips (91%). With radiological evidence of aseptic loosening of the acetabular component as the end-point, the survivorship at a mean of 5.8 years after surgery was 96.4%. The use of impacted allograft chips in combination with a cemented metal-backed acetabular component and screw fixation can achieve good medium-term results in patients with acetabular bone deficiency.


Assuntos
Acetábulo/cirurgia , Artroplastia de Quadril/métodos , Transplante Ósseo/métodos , Acetábulo/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Cimentos Ósseos , Parafusos Ósseos , Cimentação/métodos , Feminino , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Luxação do Quadril/etiologia , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Complicações Pós-Operatórias/etiologia , Falha de Prótese , Radiografia , Reoperação , Resultado do Tratamento
10.
Am J Chin Med ; 34(1): 13-21, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16437735

RESUMO

Traditional Chinese medicine (TCM) has been used for prevention and treatment of severe acute respiratory syndrome (SARS) in Hong Kong during the outbreak in spring 2003. We investigated the immunomodulating effects of an innovative TCM regimen derived from two herbal formulas (Sang Ju Yin and Yu Ping Feng San) for treating febrile diseases. Thirty-seven healthy volunteers were given the oral TCM regimen daily for 14 days. Peripheral venous blood samples were taken on days 0, 15 and 29 for hematology, biochemistry and immunology tests, including the measurement of blood lymphocyte subsets and plasma T-helper lymphocyte types 1 and 2 cytokines and receptor. After 3 months, 23 of the volunteers participated in a control study without TCM treatment for the same time course of blood tests. Two volunteers withdrew on day 2, due to headache and dizziness. All others remained well without any side effects. No participants showed significant changes in their blood test results, except that the T-lymphocyte CD4/CD8 ratio increased significantly from 1.31 +/- 0.50 (mean +/- SD) on day 0 to 1.41 +/- 0.63 on day 15 (p < 0.02), and reduced to 1.32 +/- 0.47 on day 29 (p < 0.05). In the control study, there were no changes in the CD4/CD8 ratio. The transient increase in CD4/CD8 ratio was likely due to the TCM intake. We postulate that the administration of the innovative TCM may have beneficial immunomodulatory effects for preventing viral infections including SARS.


Assuntos
Relação CD4-CD8 , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
Aliment Pharmacol Ther ; 19(4): 401-6, 2004 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-14871279

RESUMO

BACKGROUND: Hepatitis B virus infection is an important aetiological factor for hepatocellular carcinoma. Clusters of hepatocellular carcinoma have been observed in families infected with hepatitis B virus. AIM: To investigate the prevalence and characteristics of hepatocellular carcinoma associated with familial hepatitis B virus in Hong Kong. METHODS: Hepatitis B virus patients were screened for familial hepatocellular carcinoma using a standardized questionnaire. The clinical features of patients with familial hepatocellular carcinoma were compared with those of 118 patients with sporadic hepatocellular carcinoma attending the clinic during the same period. RESULTS: A total of 5080 patients were interviewed. Validation of the questionnaire indicated that the reliability was high. There were 22 families with familial hepatocellular carcinoma, giving a prevalence of 4.3 families/1000 hepatitis B virus carriers. The mean age of onset was 48.5 +/- 13 years in familial hepatocellular carcinoma and 62 +/- 11 years in sporadic hepatocellular carcinoma (P = 0.005). The ages of onset were 59 +/- 11, 40 +/- 10 and 18 +/- 4 years in the first, second and third generations, respectively (P < 0.0001), suggesting an anticipation phenomenon. Familial hepatocellular carcinoma patients were more likely to present with pain (70% vs. 10%, P < 0.0001), but not on routine screening (14% vs. 52%, P < 0.0001), than sporadic hepatocellular carcinoma patients. CONCLUSION: The prevalence of familial hepatocellular carcinoma is significant in Hong Kong. These patients show specific clinical features when compared with patients with sporadic hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular/genética , Hepatite B Crônica/genética , Neoplasias Hepáticas/genética , Adolescente , Adulto , Idade de Início , Idoso , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/virologia , Características da Família , Feminino , Hepatite B Crônica/complicações , Hepatite B Crônica/epidemiologia , Hong Kong/epidemiologia , Humanos , Testes de Função Hepática , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Linhagem , Prevalência
12.
Ann N Y Acad Sci ; 626: 438-44, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2058965

RESUMO

Assisted reproductive techniques (ART) have contributed tremendously to alleviating infertility in childless couples. However, the "take-home baby" rate for in vitro fertilization (IVF) has been much below the rate for normal fertile couples and for the other tubal procedures such as gamete intrafallopian transfer (GIFT) and tubal embryo transfer (TET). It was therefore speculated that the tubal environment might be playing an important role towards the viability of the embryo and that, in IVF, 4-6 cell stage embryos that were usually replaced directly into the uterus might not be receiving the beneficial effects of the tubal environment. Pronuclear stage human and mouse embryos were thus cocultured with reproductive and other somatic cell types to evaluate the quality of the various cleaving stages and the percentage yield of blastocysts. Human ampullary cell cultures were established in 6 to 7 days and kept alive through one menstrual cycle. Cleavage to the compacted and cavitating stages was achieved in 78% and 69%, respectively, of human embryos cocultured in 24-48 hour human ampullary subcultures as compared to 50% and 33%, respectively, for embryos grown in culture medium alone. The percentages of expanded blastocysts and hatching stages in such cocultures were not significantly different from those of controls. However, human ampullary and cumulus and mouse ampullary and muscle fibroblast cultures supported cleavage and development of mouse embryos up to the hatching stages as well as or better than controls. It thus appears that there is no absolute specificity for a reproductive tract source of cocultured cells and that the beneficial effects of ampullary and cumulus cells are not species-specific. The coculture system also appears to overcome the embryonic blocks of the human and mouse, which may be mediated via growth factors that activate the embryonic genome.


Assuntos
Técnicas Reprodutivas , Animais , Linhagem Celular , Fase de Clivagem do Zigoto , Técnicas de Cultura/métodos , Embrião de Mamíferos/metabolismo , Tubas Uterinas/citologia , Feminino , Fertilização , Previsões , Substâncias de Crescimento/metabolismo , Humanos , Camundongos
13.
QJM ; 96(9): 643-8, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12925719

RESUMO

BACKGROUND: Hydrocephalus is a common complication of tuberculous meningitis (TBM). AIM: To study the incidence, associated clinical features, and impact on outcome of hydrocephalus at presentation in TBM. DESIGN: Observational study. SETTING: Regional hospital serving 500,000 people. METHODS: Adult patients with TBM were studied over 57 months. Those with hydrocephalus on initial CT scan were assessed by neurosurgeons. Clinical, neuroradiological, and biochemical features of patients with hydrocephalus upon presentation were compared to those without initial hydrocephalus. RESULTS: Of 31 TBM patients during the study period, nine (29.0%) had hydrocephalus at presentation, and eight of them (25.8% of all) underwent urgent neurosurgical intervention. Of the 22 patients without initial hydrocephalus, hydrocephalus developed after commencement of chemotherapy in one patient only. Hydrocephalus at presentation was associated with a longer duration of presenting symptoms (p = 0.01), ataxia (p = 0.001), later stages of TBM (p = 0.045), a longer delay before commencement of anti-tuberculous chemotherapy (p = 0.001), stroke (p = 0.012), and a poor outcome at 1 year (p = 0.001). DISCUSSION: Hydrocephalus upon presentation is common in our TBM patients. This may be a poor prognostic marker associated with severe TBM and a higher risk of stroke.


Assuntos
Hidrocefalia/etiologia , Tuberculose Meníngea/complicações , Adulto , Anticorpos Antivirais/análise , Antituberculosos/uso terapêutico , Feminino , HIV/imunologia , Humanos , Hidrocefalia/líquido cefalorraquidiano , Hidrocefalia/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/isolamento & purificação , Doenças do Sistema Nervoso/complicações , Prognóstico , Fatores de Risco , Acidente Vascular Cerebral/complicações , Fatores de Tempo , Tuberculose Meníngea/líquido cefalorraquidiano , Tuberculose Meníngea/tratamento farmacológico
14.
Fertil Steril ; 57(1): 129-33, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1730306

RESUMO

OBJECTIVE: To examine the fertilization rates of 48-hour unfertilized oocytes inseminated with fertile donor sperm and to evaluate the cleavage and cytogenetics of ensuing embryos. DESIGN: Prospective. SETTING: Assisted reproductive technology (ART) program. PATIENTS: Four hundred ninety-seven unfertilized oocytes from 97 ART patients were categorized into four groups. A (zona-intact) and B (zona-free) were from patients with partial fertilization failure, whereas C (zona-intact) and D (zona-free) were total fertilization failures. RESULTS: Fertilization rates in groups A and B were significantly higher than C and D (33.2% to 60.9% versus 20.0% to 48.1%; P less than 0.01). Zona-free oocytes had higher fertilization rates than zona-intact oocytes (48.1% to 60.9% versus 20.0% to 32.2%). Multiple pronuclei were high in zona-free oocytes (33.1% to 41.3%). Forty-eight to 54% of embryos generated after donor insemination had chromosome anomalies (mosaicism, aneuploidy, pulverization). CONCLUSIONS: One cause of total fertilization failure appears to lie in intrinsic oocyte problems confined to the zona and oolemma. The fertilization of 48-hour unfertilized oocytes may be of some value in diagnosing fertilization failure in ART patients.


Assuntos
Fertilização in vitro , Oócitos/fisiologia , Divisão Celular , Aberrações Cromossômicas , Transtornos Cromossômicos , Feminino , Humanos , Masculino , Oócitos/citologia , Estudos Prospectivos , Motilidade dos Espermatozoides , Interações Espermatozoide-Óvulo , Zona Pelúcida/fisiologia
15.
Fertil Steril ; 61(5): 976-8, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8174741

RESUMO

Embryonic behavior to blastocyst, hatching, and hatched stages were evaluated in 77, four-cell human embryos that were first grown in oviductal cell coculture and then equally allotted at the eight-cell stage to two coculture systems in a serum-free medium (34 continued on oviductal monolayers, 32 on endometrium monolayers). Sixty-three percent and 40% of embryos expanded and hatched in the sequential oviductal-endometrial coculture system when compared with 41% and 9% in the oviductal system alone, respectively. The sequential coculture system appears to be an improved system over the single human oviductal coculture system.


Assuntos
Embrião de Mamíferos/fisiologia , Endométrio/fisiologia , Tubas Uterinas/fisiologia , Técnicas de Cultura , Feminino , Humanos
16.
Fertil Steril ; 56(2): 179-91, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2070845

RESUMO

One of the contributory causes to poor PRs in assisted reproduction has been the decreased viability of transferred embryos and the transfer of four-cell embryos into an environment that naturally would be receptive only to 5-day-old blastocysts. In this paper, we have reviewed our own work and that of others on the role of tubal ampullary cells (cocultures) to mimic the in vivo environment to bring about improved embryo quality and an increased number of blastocysts for replacement in IVF patients. The establishment, maintenance, and behavior of human tubal cell lines is first presented, followed by their use as cocultures for fertilization and cleavage of embryos. The mode of action, specificity, and cryopreservation of ampullary cells are also discussed. The currently available results of pregnancies after cocultures are presented together with future aspects of research that are necessary to refine the coculture system. The ultimate aim is to mimic in vivo conditions in vitro, so that at least the PRs of assisted conception can be parallel to normal fecundity in the human. Therefore, a very attractive future includes the freezing of blastocysts generated from coculture, thawing, and replacing them in natural cycles.


Assuntos
Células Cultivadas , Transferência Embrionária , Desenvolvimento Embrionário e Fetal , Tubas Uterinas/citologia , Animais , Blastocisto/citologia , Criopreservação , Meios de Cultura , Transmissão de Doença Infecciosa , Feminino , Humanos , Masculino , Gravidez , Motilidade dos Espermatozoides
17.
Fertil Steril ; 58(3): 569-74, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1521654

RESUMO

OBJECTIVE: To evaluate the embryonic behavior in vitro and the pregnancy and implantation rates of embryos grown in a human ampullary cell coculture system. DESIGN: In a prospective study, two pronuclei embryos were cultured on human ampullary feeder layers up to the two to six-cell and blastocyst stages and replaced either as tubal, uterine, or sequential transfers. SETTING: Assisted reproductive technology program in a university-based hospital. PATIENTS: Fifty women with a mean age of 35.6 years who went through a single coculture cycle. Thirty of the patients were admitted for in vitro fertilization (IVF) and 20 for tubal embryo transfer (TET). RESULTS: The overall clinical pregnancy rate (PR) for all 50 patients was 44% per cycle (IVF, 37%; TET, 55%) and the implantation rate was 31.8% (IVF, 31.0%; TET, 32.6%). Sixty-eight percent of pregnant patients were over 35 years, and 68% had two previously failed assisted reproduction cycles. Five of 9 patients who received sequential transfers became pregnant. Three of the 22 pregnancies aborted (2 after sequential transfer), and there was one ectopic. Overall, 88% of two to six-cell stage embryos were of good quality. CONCLUSIONS: The human ampullary coculture system produces better quality embryos, increased numbers of blastocysts with improved PRs and implantation rates. The beneficial effects of the feeder layer may be through the release of embryotrophic factors and detoxification of the medium by the cells. Coculture is a new concept in assisted reproduction and has tremendous potential in boosting conception rates by mimicking the in vivo environment.


Assuntos
Transferência Embrionária , Desenvolvimento Embrionário e Fetal , Tubas Uterinas/fisiologia , Adulto , Blastocisto/fisiologia , Técnicas de Cultura , Epitélio/fisiologia , Tubas Uterinas/citologia , Feminino , Fertilização in vitro , Humanos , Gravidez , Estudos Prospectivos
18.
Fertil Steril ; 56(1): 66-70, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2065806

RESUMO

STUDY OBJECTIVE: To examine the chromosome makeup of fragmented human embryos. DESIGN: Prospective. SETTING: Assisted reproductive technology (ART) program. PATIENTS: One hundred twenty-one poor-quality embryos from 58 patients 31 to 40 years of age admitted for an ART program were examined for chromosome makeup. RESULTS: Chromosome anomalies were observed in 31.9% (29/91) of poor-quality embryos, 19.8% (18/91) displayed mosaicism (diploid/haploid, diploid/triploid, diploid/aneuploid), 5.5% (5/91) showed polyploidy, 2.2% (2/91) had pulverized chromosomes, 2.2% (2/91) revealed aneuploidy, 1.1% (1/91) had prematurely condensed chromosomes, and 1.1% (1/91) had structural rearrangements involving chromosome number 2. The mean age of patients showing anomalies (36.5 years) was not significantly higher than the mean for the entire group (35.5 years). CONCLUSIONS: The incidence of chromosome anomalies in fragmented human embryos is high. These anomalies originate either in the gametes or through mitotic nondisjunction within the embryos. It is not advisable to replace such embryos into patients going through in vitro fertilization.


Assuntos
Aberrações Cromossômicas , Embrião de Mamíferos/ultraestrutura , Fertilização in vitro , Adulto , Feminino , Humanos , Infertilidade/terapia , Não Disjunção Genética , Ploidias , Gravidez , Estudos Prospectivos
19.
Fertil Steril ; 72(3): 533-8, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10519630

RESUMO

OBJECTIVE: To study the effects of peritoneal macrophages on endometrial cellular proliferation in an in vitro coculture model and to compare the magnitude of these effects between macrophages from women with endometriosis and normal women. DESIGN: Controlled study of peritoneal macrophage function. SETTING: University hospital. PATIENT(S): Patients with a normal peritoneal cavity (n = 15) and with pelvic endometriosis (n = 20) undergoing laparoscopy. INTERVENTION(S): Peritoneal macrophages were cocultured with endometrial epithelial and stromal cells; endometrial cell cultures without macrophage coculture acted as controls. MAIN OUTCOME MEASURE(S): Endometrial cellular proliferation measured by 3H-thymidine incorporation. RESULT(S): Endometrial epithelial cells cocultured with peritoneal macrophages from women with endometriosis showed significantly increased proliferation compared with cocultures using macrophages from normal women when assessed at 24 hours (1.56 versus 1.03 times, respectively, over control) and at 72 hours (1.55 versus 1.10 times over control). Endometrial stromal cells cocultured with peritoneal macrophages from women with endometriosis similarly exhibited increased proliferation compared with cocultures using macrophages from normal women when assessed at 24 hours (1.65 versus 1.17 times over control) and at 72 hours (1.65 versus 1.21 times over control). CONCLUSION(S): Peritoneal macrophages of patients with endometriosis stimulate cellular proliferation of endometrial epithelial and stromal cells in vitro.


Assuntos
Endometriose/patologia , Endométrio/patologia , Macrófagos Peritoneais/fisiologia , Adulto , Líquido Ascítico/patologia , Líquido Ascítico/fisiopatologia , Divisão Celular , Técnicas de Cocultura , Células Epiteliais/patologia , Feminino , Humanos , Células Estromais/patologia
20.
Adv Neurol ; 79: 351-74, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10514826

RESUMO

Among the 40 to 100 million persons with epilepsy worldwide and the 2 to 2.5 million persons with epilepsies in the United States, approximately 50% have generalized epilepsies. Among all epilepsies, the most common are juvenile myoclonus epilepsy (JME) with 10% to 30% of cases, childhood absence epilepsy (CAE) with 5% to 15% of cases, and pure grand mal on awakening with 22% to 37% of cases. In the last decade, six different chromosomal loci for common generalized epilepsies have been identified. These include two separate loci for JME in chromosomes 6p and 15q. The epilepsy locus in chromosome 6p expresses the phenotypes of classic JME, pure grand mal on awakening, and possibly JME mixed with absences. Two separate loci also are present for pyknoleptic CAE, namely, CAE that evolves to JME in chromosome 1p and CAE with grand mal in chromosome 8q24. Pandolfo et al. from the Italian League Against Epilepsy have reported two other putative susceptibility loci for idiopathic generalized epilepsies, namely, grand mal and generalized spike waves 35l in chromosome 3p and generalized epilepsies with febrile convulsions, grand mal, JME, absences, and electroencephalographic spike waves in 8q24. This chapter reports on the debate concerning whether there may be two separate epilepsy loci in chromosome 6p, one in the HLA region and one below HLA. The chapter then discusses the progress made in our laboratories as a result of the Genetic Epilepsy Studies (GENES) International Consortium. We discuss (a) the 2 to 6 cM critical region for classic JME located some 20 cM below HLA in chromosome 6p, (b) the 7-cM area for pyknoleptic CAE that evolves to JME in chromosome 1p, and (c) the 3.2 cM area for pyknoleptic CAE with grand mal and irregular 3 to 4 Hz spike waves in chromosome 8q24. We discusses efforts underway to refine the genetic map of JME in chromosome 6p11 and the advances in physical mapping and positioning of candidate genes, such as the gamma-aminobutyric acid receptor gene, the potassium channel gene of the long-QT family (KvLQT), named KCNQ3, and the human homologue of the mouse jerky gene for CAE in chromosome 8q24 and JME in chromosome 6p11.


Assuntos
Mapeamento Cromossômico , Clonagem Molecular , Epilepsia Tipo Ausência/genética , Epilepsia Generalizada/genética , Epilepsia Mioclônica Juvenil/genética , Cromossomos Humanos Par 6/genética , Cromossomos Humanos Par 8/genética , Eletroencefalografia , Epilepsia Tipo Ausência/fisiopatologia , Epilepsia Tônico-Clônica/genética , Epilepsia Tônico-Clônica/fisiopatologia , Ligação Genética , Antígenos HLA/genética , Humanos , Linhagem , Recombinação Genética
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