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3.
Plast Reconstr Surg ; 145(5): 1125-1133, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32332524

RESUMO

BACKGROUND: Direct-to-implant breast reconstruction continues to grow in popularity among reconstructive breast surgeons and patients alike. Women with large breasts and ptosis are often thought not to be candidates for nipple sparing or direct-to-implant reconstruction. The authors utilized a single-stage, nipple-sparing, direct-to-implant reconstruction with simultaneous mastopexy, while the nipple-areolar complex was kept viable on an inferiorly based adipodermal flap in a single stage. They report their experience and outcomes using this approach in women with breast ptosis and/or macromastia. METHODS: The authors reviewed all direct-to-implant reconstructions with simultaneous nipple-sparing mastopexies performed from June of 2015 to March of 2019. Sixty-five patients and 125 breast reconstructions were analyzed. RESULTS: Among the 65 patients (125 breast reconstructions), 15 (23 percent) had implants placed in the prepectoral space, and 50 (77 percent) had them placed subpectorally. Forty-seven patients (72 percent) had acellular dermal matrix used. Partial nipple-areolar complex necrosis occurred in six patients (9 percent). Other complications included partial mastectomy flap necrosis (n = 8 patients, 12 percent), implant exposure (n = 3, 4 percent), infection (n = 1, 1 percent), capsular contracture (n = 4, 6 percent), and reoperation (n = 11, 16 percent). Mean follow-up was 17 months (range, 3 to 47 months). There have been no cancer recurrences reported in any participants to date. CONCLUSIONS: Nipple-sparing mastectomy with mastopexy and immediate direct-to-implant reconstruction dramatically improved the authors' results for implant-based breast reconstruction patients. The higher than expected explantation rate of 7 percent early in the study has since improved. This approach provides an opportunity to expand indications for nipple-sparing mastectomy and direct-to-implant reconstruction to women with breast ptosis and/or macromastia. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.


Assuntos
Mama/anormalidades , Hipertrofia/cirurgia , Mamoplastia/métodos , Mastectomia Subcutânea/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Retalhos Cirúrgicos/transplante , Derme Acelular , Adulto , Mama/cirurgia , Implantes de Mama/efeitos adversos , Neoplasias da Mama/cirurgia , Estética , Feminino , Seguimentos , Humanos , Mamoplastia/efeitos adversos , Mamoplastia/instrumentação , Pessoa de Meia-Idade , Mamilos/cirurgia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Resultado do Tratamento
4.
Early Hum Dev ; 91(3): 239-42, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25706319

RESUMO

OBJECTIVE: During an early second-trimester transvaginal ultrasound anomaly scan, pressure is applied to the uterus, and the fetus is often rotated manually to allow scanning of its various organs. This study was designed to determine if performing a transvaginal ultrasound anomaly scan during the early second trimester of pregnancy is associated with adverse perinatal outcome or cord entanglement. METHODS: During the 4.5year study period we prospectively collected cases of routine ultrasound scans at 14-17weeks gestation performed as anomaly screening, together with perinatal outcome. The study population consisted of 164 women who underwent a transvaginal approach, and the control population consisted of 224 women in which a transabdominal approach was used. Data on perinatal parameters was collected from delivery charts from the four local hospitals. RESULTS: There were more operative deliveries (vaginal or Cesarean) in the transvaginal scan group (32% vs. 23%, p=0.05). However, on multiple logistic regression analysis vaginal scans were not associated with increased operative delivery rates with an adjusted odds ratio of 1.47 and a 95% confidence interval of 0.85-2.54. There were no other clinically significant differences in perinatal outcomes, or in cord entanglement. CONCLUSIONS: Transvaginal ultrasound anomaly scan conducted in the early second trimester of pregnancy is a safe procedure for the fetus.


Assuntos
Ultrassonografia Pré-Natal/efeitos adversos , Adulto , Estudos de Casos e Controles , Endossonografia/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Segundo Trimestre da Gravidez , Ultrassonografia Pré-Natal/métodos
5.
Diabetes Metab Res Rev ; 23(4): 292-8, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17124720

RESUMO

BACKGROUND: Treatment with DiaPep277, a peptide derived from HSP60, has been shown to preserve beta-cell function in non-obese diabetic mouse (NOD) mice and in a trial with newly diagnosed human patients with type 1 diabetes treated over a 10-month period. This article extends the clinical trial observations to a total of 20 months of treatment to determine the safety and the effects of repeated doses of DiaPep277 on endogenous insulin secretion, metabolic control, and exogenous insulin requirements. METHODS: Thirty-five male patients (aged 16-58) with a basal C-peptide greater than 0.1 nmol/L were assigned to periodic treatment with DiaPep277 (1 mg) or placebo for a 12-month treatment and 18-month observation protocol, later extended to an additional year of treatment. Stimulated C-peptide, HbA1c, and an exogenous insulin dose were the clinical endpoints. RESULTS: At 18 months, stimulated C-peptide concentrations had fallen in the placebo group (p = 0.0005) but were maintained in the DiaPep277 group. The need for exogenous insulin was higher in the placebo group than in the DiaPep277 group. Mean HbA1c concentrations were similar in both groups. After extension of the study, patients continuing treatment with DiaPep277 and those switched from placebo to DiaPep277 manifested a trend towards a greater preservation of beta-cell function compared to patients maintained on or switched to placebo. The safety profile of DiaPep277 was similar between the treatment and placebo groups, and no drug-related adverse events occurred. CONCLUSIONS: Periodic treatment of subjects with DiaPep277 over 2 years was safe and associated preservation of endogenous insulin secretion up to 18 months was observed.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Peptídeos/uso terapêutico , Adolescente , Adulto , Peptídeo C/sangue , Chaperonina 60 , Diabetes Mellitus Tipo 1/sangue , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/metabolismo , Insulina/uso terapêutico , Secreção de Insulina , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos , Peptídeos/administração & dosagem
6.
Diabetes Metab Res Rev ; 23(4): 286-91, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17124721

RESUMO

BACKGROUND: Type 1 diabetes mellitus (T1DM) is a T-cell-mediated autoimmune disease that leads to the destruction of insulin-producing beta cells. Treatment with DiaPep277, a peptide derived from heat-shock protein 60 (hsp60), has been found to slow the deterioration of beta-cell function after clinical onset of diabetes in NOD mice and human adults. Our aim was to evaluate the efficacy and safety of DiaPep277 treatment in attenuating beta-cell destruction in children with recent-onset T1DM. METHODS: A prospective, randomized, double-blind, phase II design was used. The sample included 30 children (19 males) aged 7-14 years who had been diagnosed with T1DM from 53 to 116 days previously, and had basal C-peptide concentrations above 0.1 nmol/L. The children were randomized to receive subcutaneous injections of 1 mg DiaPep277 (15 patients) or 40 mg mannitol (placebo) at entry and at 1, 6, and 12 months. The duration of follow-up was 18 months. The groups were compared for stimulated C-peptide level, exogenous insulin dose, and HbA1c concentration. RESULTS: C-peptide levels similarly decreased over time in the DiaPep277- and placebo-treated patients. There was no significant difference in insulin dose or HbA1c concentration between the groups at any time point. No serious drug-related adverse effects were recorded throughout the study period. CONCLUSIONS: One-year treatment with DiaPep277 at a dosage of 1 mg is safe for use and well tolerated in children with recent-onset T1DM. However, it appears to have no beneficial effect in preserving beta-cell function or improving metabolic control.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Peptídeos/uso terapêutico , Adolescente , Peptídeo C/sangue , Chaperonina 60 , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Seguimentos , Gastroenterite/induzido quimicamente , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico , Injeções Subcutâneas , Insulina/efeitos adversos , Insulina/uso terapêutico , Masculino , Fragmentos de Peptídeos , Peptídeos/administração & dosagem , Peptídeos/efeitos adversos , Resultado do Tratamento
7.
J Virol ; 79(2): 1045-52, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15613333

RESUMO

Type 1 diabetes acceleration in nonobese diabetic (NOD) mice through coxsackievirus B4 (CVB4) infection requires a preexisting critical mass of autoreactive T cells in pancreatic islets, and in the absence of this insulitic threshold, CVB4 infection leads to long-term disease protection. To understand this acceleration and protection process, we challenged 8- and 12-week-old NOD mice containing a disruption in interleukin-4 (IL-4) or gamma interferon (IFN-gamma) genes (NOD IL-4-/- and NOD IFN-gamma-/-, respectively) with a diabetogenic, pancreatropic Edwards strain of CVB4. The elimination of IL-4 did not alter the rate of insulitis or diabetes development in NOD mice, while the elimination of IFN-gamma delayed these events several weeks. CVB4 infection in 8-week-old mice only significantly accelerated the onset of diabetes in a subset of standard, but not IL-4- or IFN-gamma-deficient, NOD mice. Long-term diabetes protection was established in standard NOD mice as well as in the NOD IFN-gamma-/- mice that did not rapidly develop disease following CVB4 infection at 8 weeks of age. When mice were infected at 12 weeks of age, the onset of diabetes was accelerated in NOD IL-4-/- mice, while neither acceleration nor long-term protection was elicited in NOD IFN-gamma-/- mice. No differences were observed in the kinetics of CVB4 clearance in pancreases from NOD, NOD IL-4-/-, and NOD IFN-gamma-/- mice. Collectively, these results suggest that at the insulitis threshold at which CVB4 infection can first accelerate the onset of diabetes in NOD mice, IL-4 as well as IFN-gamma contributes to this pathogenic process. The protective mechanism against diabetes elicited in NOD mice infected with CVB4 prior to the development of a critical threshold level of insulitis requires neither IL-4 nor IFN-gamma.


Assuntos
Diabetes Mellitus Tipo 1/etiologia , Enterovirus Humano B , Infecções por Enterovirus/complicações , Interferon gama/fisiologia , Interleucina-4/fisiologia , Animais , Diabetes Mellitus Tipo 1/prevenção & controle , Feminino , Ilhotas Pancreáticas/patologia , Camundongos , Camundongos Endogâmicos NOD , Pâncreas/virologia
8.
Am J Pathol ; 165(3): 1045-53, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15331427

RESUMO

Induction of heme oxygenase-1 (HO-1) is protective in tissue injury in models of allograft rejection and vascular inflammation through either prevention of oxidative damage or via immunomodulatory effects. To examine the specific role of HO-1 in modulating the immune response, we examined the differences in immune phenotype between HO-1 knockout (HO-1(-/-)) and wild-type (HO-1(+/+)) mice. Consistent with previous findings, marked splenomegaly and fibrosis were observed in HO-1(-/-) mice. The lymph nodes of HO-1-deficient mice demonstrated a relative paucity of CD3- and B220-positive cells, but no such abnormalities were observed in the thymus. Flow cytometric analysis of isolated splenocytes demonstrated no differences in the proportions of T lymphocytes, B lymphocytes or monocytes/macrophages between the HO-1(-/-) and HO-1(+/+) mice. Significantly higher baseline serum IgM levels were observed in HO-1(-/-) versus HO-1(+/+) mice. Under mitogen stimulation with either lipopolysaccharide or anti-CD3/anti-CD28, HO-1(-/-) splenocytes secreted disproportionately higher levels of pro-inflammatory Th1 cytokines as compared to those from HO-1(+/+) mice. These findings demonstrate significant differences in the immune phenotype between the HO-1(-/-) and the HO-1(+/+) mice. The absence of HO-1 correlates with a Th1-weighted shift in cytokine responses suggesting a general pro-inflammatory tendency associated with HO-1 deficiency.


Assuntos
Citocinas/metabolismo , Modelos Animais de Doenças , Heme Oxigenase (Desciclizante)/fisiologia , Inflamação/sangue , Inflamação/enzimologia , Células Th1/metabolismo , Animais , Linfócitos B/metabolismo , Complexo CD3/metabolismo , Feminino , Fibrose/enzimologia , Fibrose/patologia , Heme Oxigenase (Desciclizante)/genética , Heme Oxigenase-1 , Imunoglobulina M/sangue , Antígenos Comuns de Leucócito/metabolismo , Lipopolissacarídeos/farmacologia , Linfonodos/patologia , Macrófagos/metabolismo , Masculino , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/metabolismo , Esplenomegalia , Linfócitos T/metabolismo , Células Th1/imunologia , Transplante Homólogo
9.
Ann N Y Acad Sci ; 1005: 237-41, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14679068

RESUMO

The concept of insulin production afforded by hepatic gene therapy retains promise as a potential therapy for type 1 diabetes, but the approach has been limited by the need for strict transgene regulation in response to fluctuating levels of both glucose and insulin. Furthermore, while hepatocytes contain various glucose-responsive elements, they lack the appropriate regulated secretory system necessary for insulin release, thereby necessitating the requirement for transcriptional regulation of hepatic insulin production under the direction of a glucose-responsive promoter. To address this, we have evaluated several glucose-responsive promoters that may be used successfully for hepatic insulin production via recombinant adeno-associated virus (rAAV) therapy. Our results suggest that the human insulin promoter represents a strong candidate as a robust, glucose-responsive promoter for regulated hepatic insulin production.


Assuntos
Carcinoma Hepatocelular/metabolismo , Glucose/fisiologia , Insulina/genética , Neoplasias Hepáticas Experimentais/metabolismo , Regiões Promotoras Genéticas , Animais , Sequência de Bases , Carcinoma Hepatocelular/patologia , Primers do DNA , Frutose-Bifosfatase/genética , Glucose-6-Fosfatase/genética , Humanos , Neoplasias Hepáticas Experimentais/patologia , Camundongos , Camundongos Endogâmicos NOD , Ratos , Células Tumorais Cultivadas
10.
J Immunol ; 171(5): 2270-8, 2003 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-12928371

RESUMO

Early systemic treatment of nonobese diabetic mice with high doses of recombinant adeno-associated virus (rAAV) vector expressing murine IL-10 prevents type 1 diabetes. To determine the therapeutic parameters and immunological mechanisms underlying this observation, female nonobese diabetic mice at 4, 8, and 12 wk of age were given a single i.m. injection of rAAV-murine IL-10 (10(4), 10(6), 10(8), and 10(9) infectious units (IU)), rAAV-vector expressing truncated murine IL-10 fragment (10(9) IU), or saline. Transduction with rAAV-IL-10 at 10(9) IU completely prevented diabetes in all animals injected at all time points, including, surprisingly, 12-wk-old animals. Treatment with 10(8) IU provided no protection in the 12-wk-old injected mice, partial prevention in 8-wk-old mice, and full protection in all animals injected at 4 wk of age. All other treatment groups developed diabetes at a similar rate. The rAAV-IL-10 therapy attenuated pancreatic insulitis, decreased MHC II expression on CD11b+ cells, increased the population of CD11b+ cells, and modulated insulin autoantibody production. Interestingly, rAAV-IL-10 therapy dramatically increased the percentage of CD4+CD25+ regulatory T cells. Adoptive transfer studies suggest that rAAV-IL-10 treatment alters the capacity of splenocytes to impart type 1 diabetes in recipient animals. This study indicates the potential for immunomodulatory gene therapy to prevent autoimmune diseases, including type 1 diabetes, and implicates IL-10 as a molecule capable of increasing the percentages of regulatory cells in vivo.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/prevenção & controle , Terapia Genética/métodos , Interleucina-10/genética , Interleucina-10/uso terapêutico , Receptores de Interleucina-2/biossíntese , Subpopulações de Linfócitos T/imunologia , Adenoviridae/genética , Animais , Formação de Anticorpos/genética , Autoanticorpos/biossíntese , Linfócitos T CD4-Positivos/metabolismo , Dependovirus/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patologia , Relação Dose-Resposta Imunológica , Feminino , Vetores Genéticos , Imunidade Celular/genética , Injeções Intramusculares , Anticorpos Anti-Insulina/biossíntese , Interleucina-10/biossíntese , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Recombinação Genética , Subpopulações de Linfócitos T/metabolismo , Fatores de Tempo
11.
Diabetes ; 52(3): 708-16, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12606512

RESUMO

Islet transplantation represents a potential cure for type 1 diabetes, yet persistent autoimmune and allogeneic immunities currently limit its clinical efficacy. For alleviating the autoimmune destruction of transplanted islets, newly diagnosed NOD mice were provided a single intramuscular injection of recombinant adeno-associated viral vector encoding murine IL-10 (rAAV-IL-10) 4 weeks before renal capsule delivery of 650 syngeneic islets. A dose-dependent protection of islet grafts was observed. Sixty percent (3 of 5) of NOD mice that received a transduction of a high-dose (4 x 10(9) infectious units) rAAV-IL-10 remained normoglycemic for at least 117 days, whereas diabetes recurred within 17 days in mice that received a low-dose rAAV-IL-10 (4 x 10(8) infectious units; 5 of 5) as well as in all of the control mice (5 of 5 untreated and 4 of 4 rAAV-green fluorescent protein-transduced). Serum IL-10 levels positively correlated with prolonged graft survival and were negatively associated with the intensity of autoimmunity. The mechanism of rAAV-IL-10 protection involved a reduction of lymphocytic infiltration as well as induction of antioxidant enzymes manganese superoxide dismutase and heme oxygenase 1 in islet grafts. These studies support the utility of immunoregulatory cytokine gene therapy delivered by rAAV for preventing autoimmune disease recurrence in transplant-based therapies for type 1 diabetes.


Assuntos
Dependovirus/genética , Diabetes Mellitus Tipo 1/terapia , Terapia Genética , Interleucina-10/genética , Transplante das Ilhotas Pancreáticas , Prevenção Secundária , Animais , Autoimunidade , Diabetes Mellitus Tipo 1/imunologia , Expressão Gênica , Vetores Genéticos , Sobrevivência de Enxerto , Proteínas de Fluorescência Verde , Heme Oxigenase (Desciclizante)/biossíntese , Heme Oxigenase-1 , Inflamação/patologia , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/patologia , Proteínas Luminescentes/genética , Linfócitos/patologia , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos NOD , Músculo Esquelético/metabolismo , Superóxido Dismutase/biossíntese
12.
Transplantation ; 74(8): 1184-6, 2002 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-12438968

RESUMO

Previous studies suggest that therapeutic expression of interleukin (IL)-4 by islet cells improves their efficacy in transplantation models directed at reversing type 1 diabetes. We investigated the effects of introducing IL-4 into islets with recombinant adeno-associated virus (rAAV) on the reversal of hyperglycemia in a syngeneic marginal islet mass transplantation model. C57BL/6 islets were mock-transduced or transduced with rAAV expressing murine IL-4 (rAAV-IL-4) or rAAV expressing green fluorescent protein (rAAV-GFP) before transplantation of a marginal mass into diabetic mice. Normoglycemia was achieved in only 1/7 mice receiving rAAV-IL-4 transduced islets in comparison to 6/6 mock-transduced and 4/6 rAAV-GFP transduced animals. The failure of IL-4 expressing islets was not associated with cellular toxicity of rAAV or impairment of glucose-stimulated insulin release in vitro. Islet expression of IL-4 led to impaired metabolic function in mice receiving a marginal mass of syngeneic islets.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Interleucina-4/genética , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/metabolismo , Transdução Genética , Adenoviridae/genética , Animais , Glicemia , Vetores Genéticos , Sobrevivência de Enxerto , Insulina/metabolismo , Secreção de Insulina , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Transplante Isogênico
13.
Lancet ; 358(9295): 1749-53, 2001 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-11734230

RESUMO

BACKGROUND: Type 1 diabetes results from autoimmune destruction of insulin-producing pancreatic beta cells. The 60 kDa heat-shock protein (hsp60) is one of the known target self antigens. An immunomodulatory peptide from hsp60, p277, arrested beta-cell destruction and maintained insulin production in newly diabetic NOD mice. We did a randomised, double-blind, phase II study of peptide treatment in patients with newly diagnosed (<6 months) type 1 diabetes. METHODS: 35 patients with type 1 diabetes and basal C-peptide concentrations above 0.1 nmol/L were assigned subcutaneous injections of 1 mg p277 and 40 mg mannitol in vegetable oil (DiaPep277; n=18) at entry, 1 month, and 6 months, or three placebo injections (mannitol in vehicle; placebo; n=17). The primary endpoint was glucagon-stimulated C-peptide production. Secondary endpoints were metabolic control and T-cell autoimmunity to hsp60 and to p277 (assayed by cytokine secretion). 31 patients completed 10 months of follow-up and were included in the intention-to-treat analysis. FINDINGS: At 10 months, mean C-peptide concentrations had fallen in the placebo group (n=16) but were maintained in the DiaPep277 group (n=15; 0.26 [SD 0.11] vs 0.93 [0.35] nmol/L; p=0.039). Need for exogenous insulin was higher in the placebo than in the DiaPep277 group (0.67 [0.33] vs 0.43 [0.17] U/kg; p=0.042). Haemoglobin A1c concentrations were low (around 7%) in both groups. T-cell reactivity to hsp60 and p277 in the DiaPep277 group showed an enhanced T-helper-2 cytokine phenotype. No adverse effects were noted. INTERPRETATION: Although this study was small, treatment of newly diagnosed type 1 diabetes with DiaPep277 seems to preserve endogenous insulin production, perhaps through induction of a shift from T-helper-1 to T-helper-2 cytokines produced by the autoimmune T cells.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Proteínas de Choque Térmico/uso terapêutico , Hipoglicemiantes/uso terapêutico , Ilhotas Pancreáticas/efeitos dos fármacos , Fragmentos de Peptídeos/uso terapêutico , Adulto , Peptídeo C/biossíntese , Chaperonina 60 , Método Duplo-Cego , Humanos , Insulina/administração & dosagem , Insulina/metabolismo , Secreção de Insulina , Interleucinas/biossíntese , Ilhotas Pancreáticas/metabolismo , Masculino , Resultado do Tratamento
14.
Biochem Biophys Res Commun ; 193(3): 1224-31, 1993 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-7686748

RESUMO

Functional delta opioid receptors were expressed in Xenopus oocytes following injection of poly(A+)RNA isolated from the mouse neuroblastoma X rat glioma hybrid cell line, NG108-15. Oocytes coinjected with in vitro transcribed beta 2-adrenergic receptor mRNA and NG108-15 cell mRNA had 3-fold elevated cAMP levels following isoproterenol treatment. Application of delta opioids to these oocytes caused dose-dependent inhibition of isoproterenol-induced increase of cAMP, which was antagonized by naltrexone. This is the first demonstration of the expression of opioid receptors in Xenopus oocytes. The ability to assay expression of delta opioid receptors functionally coupled to the inhibition of adenylate cyclase in Xenopus oocytes following injection of exogenous mRNA will provide a system to investigate the relationship of molecular structure to function of opioid receptors.


Assuntos
Adenilil Ciclases/metabolismo , Analgésicos/farmacologia , AMP Cíclico/metabolismo , Encefalinas/farmacologia , Naltrexona/farmacologia , Oócitos/metabolismo , Receptores Opioides delta/biossíntese , Análise de Variância , Animais , Ala(2)-MePhe(4)-Gly(5)-Encefalina , D-Penicilina (2,5)-Encefalina , Leucina Encefalina-2-Alanina/farmacologia , Feminino , Glioma , Células Híbridas , Isoproterenol/farmacologia , Camundongos , Neuroblastoma , Oócitos/efeitos dos fármacos , Poli A/genética , Poli A/isolamento & purificação , RNA/genética , RNA/isolamento & purificação , RNA Mensageiro/metabolismo , Ratos , Receptores Opioides delta/efeitos dos fármacos , Xenopus laevis
15.
Exp Hematol ; 18(4): 322-40, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2182333

RESUMO

Thymocytes were propagated in long-term cultures supported by stromal cells of both bone marrow and thymus origin. Interleukin 2 (IL-2) supplementation augmented the cell yield and allowed detailed phenotype analysis. Within 2-3 months of culture a cell population was selected in which the expression of Thy-1 antigen persisted, CD4 and CD8 antigens gradually declined, and Pgp-1 antigen, found on less than 5% of fresh thymocytes, was strongly increased. This cultured cell population (Thy-1.2 origin) contained no detectable spleen colony-forming units (CFU-S) but efficiently repopulated the thymus of Thy-1.1-irradiated congenic mice, indicating the precursor T-cell nature of the population. Upon removal from the stroma, the T cells exhibited poor cytotoxicity towards syngeneic tumor cells. Further propagation with IL-2 in the absence of stroma resulted in the acquisition of cytotoxic ability. Replacement of the horse serum used in the above experiments with fetal calf serum resulted in accumulation of cells expressing B220 antigen. This experimental model provides the means to maintain lymphocyte precursor cells in long-term culture and to further study their differentiation in the absence of stroma, both in vitro and in vivo.


Assuntos
Células-Tronco Hematopoéticas/citologia , Linfócitos/citologia , Animais , Divisão Celular/efeitos dos fármacos , Técnicas Citológicas , Citotoxicidade Imunológica , Interleucina-2/farmacologia , Linfócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos , Proteínas Recombinantes/farmacologia , Timo/citologia , Fatores de Tempo
16.
Int J Cell Cloning ; 7(6): 373-84, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2809273

RESUMO

Long-term hemopoiesis in culture depends upon the presence of an adherent layer composed of a variety of stromal cells. A subtype of endothelial-adipocytes from the bone marrow stroma (clone 14F1.1) was previously shown to induce long-term myelopoiesis and renewal of pluripotent stem cells. One of a series of stromal cell lines and clones from mouse thymus stroma (STAC-1.2) has now been found to support long-term hemopoiesis. These marrow- and thymus-derived stromal cell clones also have lymphopoietic activities: precursor T cells, or pre-B cells accumulated in co-cultures of thymus cells and the stromal clones, as indicated by cell surface markers, T cell receptor and immunoglobulin gene rearrangements. The predominance of a cell type in these cultures depended upon the serum used to supplement the medium. Recombinant interleukin 2 (IL-2) and the 14F1.1 clone synergistically promoted the proliferation of thymocytes, while a thymus hormone, THF-gamma 2, shifted the population to a relatively mature phenotype. It is proposed that one major function of stromal cells, whether from the bone marrow or thymus, is to restrain the maturation flow and preferentially support the accumulation of cells at early differentiation stages.


Assuntos
Células da Medula Óssea , Células-Tronco Hematopoéticas/citologia , Timo/citologia , Animais , Medula Óssea/efeitos dos fármacos , Contagem de Células , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Células-Tronco Hematopoéticas/efeitos dos fármacos , Interleucina-2/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Timo/efeitos dos fármacos , Hormônios do Timo/farmacologia , Fatores de Tempo
17.
Int J Cell Cloning ; 7(5): 281-91, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2671165

RESUMO

Hemopoiesis is a multistep process involving stem cell renewal, commitment, differentiation, maturation and consequent positioning of the cells within the tissue. Stromal cells are a major component of the hemopoietic microenvironment. The in vitro culture of cloned stromal cells has enabled detailed analysis of their functions and has provided answers relating to the contribution of stromal cells to the control of hemopoiesis. Cultured stromal cells were found to support the renewal of stem cells through a mechanism that did not seem to involve already known cytokines. Cloned stromal cells from both marrow and thymus supported the in vitro accumulation of myeloid as well as T and B lymphoid cells. Thus, cloned stromal cells had the ability to induce multilineage hemopoiesis, irrespective of the organ from which they were derived. Invariably, stromal cells tended to select in culture for hemopoietic cells at early differentiation stages and restricted the accumulation of mature cells. These functions may be part of the mechanism that protects the stem cell pool from excess differentiation.


Assuntos
Hematopoese , Células-Tronco Hematopoéticas/metabolismo , Linfócitos T/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Células-Tronco Hematopoéticas/citologia , Humanos , Linfócitos T/citologia
18.
Nat Immun Cell Growth Regul ; 7(3): 185-92, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3262823

RESUMO

Hemopoiesis is a sequence of events initiated by the self-renewal of pluripotent stem cells followed by a series of differentiation steps and completed in the formation of distinct tissue patterns. Differentiation and self-renewal are antagonistic processes. A mechanism that attenuates the differentiation flow is obligatory to prevent the exhaustion of the stem cell pool. We suggest that stromal cells from the bone marrow control stem cell renewal through a mechanism that does not require colony-stimulating factors. The organization of cells within the tissue and their specific localization is suggested to be directed by stromal cell activities other than differentiation inducers. These stromal cell activities restrict differentiation or accumulation of mature cells. They are therefore designated as 'Restrictins'.


Assuntos
Fatores Biológicos/fisiologia , Hematopoese , Animais , Ensaio de Unidades Formadoras de Colônias , Fatores Estimuladores de Colônias/fisiologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Técnicas In Vitro , Camundongos , Modelos Biológicos
19.
Int J Cell Cloning ; 5(4): 289-301, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3624917

RESUMO

We derived stromal cell lines from mouse thymus using methods previously established for bone marrow stroma. Two main morphologically distinct groups of cell strains emerged: epithelioid and mixed fibroblast-macrophage. Transmission electron microscopy revealed frequent junctional-complex formations between adjacent cells, a feature that characterized almost all of the thymus stromal lines, but was confined to only one of the five distinct subtypes of cell lines from bone marrow. In contrast to marrow stromal cells, the thymus-derived cell lines were all negative with fat-detecting reagents, had low acid phosphatase and no basic phosphatase activities and were unable to support the in vitro proliferation of myeloid progenitor cells (CFU-gm). Leukemia cell inhibitory activity (LCIA) was detected in one of the thymus stromal cell lines. The differences observed between cell lines derived from the stroma of the thymus and those from bone marrow may relate to the functional specificities of these organs.


Assuntos
Timo/citologia , Animais , Células da Medula Óssea , Linhagem Celular , Células Epiteliais , Fibroblastos/citologia , Hematopoese , Junções Intercelulares/ultraestrutura , Macrófagos/citologia , Camundongos , Microscopia Eletrônica
20.
Proc Natl Acad Sci U S A ; 83(12): 4547-51, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3459188

RESUMO

We have examined the mechanism by which stromal cells from the microenvironment of the bone marrow restricted the in vitro growth of certain hemopoietic tumors. A series of leukemia cell lines was used to monitor biological activities of stromal cell lines representing five distinct subtypes. Only an endothelial-like clone derived from mouse stroma (MBA-2.1) was consistently found to produce a cell-surface-associated glycoprotein that selectively inhibited the growth of plasmacytomas. The factor, designated leukemia cell inhibitory activity (LCIA), was not detected in anchorage-dependent cells of nonhemopoietic origin. Tumors of the lymphoid lineage and plasmacytomas in particular were the most sensitive to LCIA. Myeloid, macrophage, and erythroleukemia tumors were resistant to the factor, as were normal hemopoietic target cells including pluripotent stem cells, myeloid progenitor cells, and mitogen-stimulated spleen cells. Fractionation of trypsin-released proteins from MBA-2.1 cells by gel filtration and affinity binding to concanavalin A-Sepharose revealed two types of inhibitors; one was the specific leukemia cell inhibitor (i.e., LCIA); the other, present at a lower titer, was non-target-cell specific. The high sensitivity of plasmacytomas to LCIA versus the resistance of normal stem cells may be utilized for selective elimination of plasma cell tumors from bone marrow inocula.


Assuntos
Medula Óssea/fisiologia , Linfoma/patologia , Animais , Antineoplásicos , Células da Medula Óssea , Diferenciação Celular , Linhagem Celular , Endotélio/fisiologia , Glicoproteínas/isolamento & purificação , Inibidores do Crescimento , Camundongos , Plasmocitoma/patologia
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