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1.
Soc Sci Med ; 346: 116660, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484417

RESUMO

BACKGROUND: In 2020, 2.8 million people required substance use disorder (SUD) treatment in nonmetropolitan or 'rural' areas in the U.S. Among this population, only 10% received SUD treatment from a specialty facility, and 1 in 500 received medication for opioid use disorder (MOUD). We explored the context surrounding barriers to SUD treatment in the rural United States. METHODS: We conducted semi-structured, in-depth interviews from 2018 to 2019 to assess barriers to SUD treatment among people who use drugs (PWUD) across seven rural U.S. study sites. Using the social-ecological model (SEM), we examined individual, interpersonal, organizational, community, and policy factors contributing to perceived barriers to SUD treatment. We employed deductive and inductive coding and analytical approaches to identify themes. We also calculated descriptive statistics for participant characteristics and salient themes. RESULTS: Among 304 participants (55% male, mean age 36 years), we identified barriers to SUD treatment in rural areas across SEM levels. At the individual/interpersonal level, relevant themes included: fear of withdrawal, the need to "get things in order" before entering treatment, close-knit communities and limited confidentiality, networks and settings that perpetuated drug use, and stigma. Organizational-level barriers included: strict facility rules, treatment programs managed like corrections facilities, lack of gender-specific treatment programs, and concerns about jeopardizing employment. Community-level barriers included: limited availability of treatment in local rural communities, long distances and limited transportation, waitlists, and a lack of information about treatment options. Policy-level themes included insurance challenges and system-imposed barriers such as arrest and incarceration. CONCLUSION: Our findings highlight multi-level barriers to SUD treatment in rural U.S. communities. Salient barriers included the need to travel long distances to treatment, challenges to confidentiality due to small, close-knit communities where people are highly familiar with one another, and high-threshold treatment program practices. Our findings point to the need to facilitate the elimination of treatment barriers at each level of the SEM in rural America.


Assuntos
Transtornos Relacionados ao Uso de Opioides , População Rural , Humanos , Estados Unidos , Masculino , Adulto , Feminino , Pesquisa Qualitativa , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Estigma Social
2.
Biochim Biophys Acta ; 1851(5): 641-56, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25677822

RESUMO

A pronounced heterogeneity between hepatocytes in subcellular structure and enzyme activities was discovered more than 50years ago and initiated the idea of metabolic zonation. In the last decades zonation patterns of liver metabolism were extensively investigated for carbohydrate, nitrogen and lipid metabolism. The present review focuses on zonation patterns of the latter. We review recent findings regarding the zonation of fatty acid uptake and oxidation, ketogenesis, triglyceride synthesis and secretion, de novo lipogenesis, as well as bile acid and cholesterol metabolism. In doing so, we expose knowledge gaps and discuss contradictory experimental results, for example on the zonation pattern of fatty acid oxidation and de novo lipogenesis. Thus, possible rewarding directions of further research are identified. Furthermore, recent findings about the regulation of metabolic zonation are summarized, especially regarding the role of hormones, nerve innervation, morphogens, gender differences and the influence of the circadian clock. In the last part of the review, a short collection of models considering hepatic lipid metabolism is provided. We conclude that modeling, despite its proven benefit for understanding of hepatic carbohydrate and ammonia metabolisms, has so far been largely disregarded in the study of lipid metabolism; therefore some possible fields of modeling interest are presented.


Assuntos
Ácidos Graxos/metabolismo , Hepatócitos/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Modelos Biológicos , Animais , Hepatócitos/enzimologia , Humanos , Fígado/citologia , Fígado/enzimologia
3.
Biochim Biophys Acta ; 1841(1): 62-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23999488

RESUMO

A hallmark of the nonalcoholic fatty liver disease is the accumulation of lipids. We developed a mathematical model of the hepatic lipid dynamics to simulate the fate of fatty acids in hepatocytes. Our model involves fatty acid uptake, lipid oxidation, and lipid export. It takes into account that storage of triacylglycerol within hepatocytes leads to cell enlargement reducing the sinusoids radius and impairing hepatic microcirculation. Thus oxygen supply is reduced, which impairs lipid oxidation. The analysis of our model revealed a bistable behavior (two stable steady states) of the system, in agreement with histological observations showing distinct areas of lipid accumulation in lobules. The first (healthy) state is characterized by intact lipid oxidation and a low amount of stored lipids. The second state in our model may correspond to the steatotic cell; it is marked by a high amount of stored lipids and a reduced lipid oxidation caused by impaired oxygen supply. Our model stresses the role of insufficient oxygen supply for the development of steatosis. We discuss implications of our results in regard to the experimental design aimed at exploring lipid metabolism reactions under steatotic conditions. Moreover, the model helps to understand the reversibility of lipid accumulation and predicts the reversible switch to show hysteresis. The system can switch from the steatotic state back to the healthy state by reduction of fatty acid uptake below the threshold at which steatosis started. The reversibility corresponds to the observation that caloric restriction can reduce the lipid content in the liver.


Assuntos
Fígado Gorduroso/metabolismo , Hepatócitos/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Modelos Biológicos , Animais , Ácidos Graxos/metabolismo , Fígado Gorduroso/patologia , Hepatócitos/patologia , Humanos , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica , Oxirredução , Triglicerídeos/metabolismo
4.
Conserv Biol ; 27(2): 270-80, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23369059

RESUMO

Despite widespread recognition of the major threat to tropical forest biological diversity and local food security posed by unsustainable bushmeat hunting, virtually no long-term studies tracking the socioecological dynamics of hunting systems have been conducted. We interviewed local hunters and collected detailed hunting data to investigate changes in offtake and hunter characteristics over 10 years (2001-2010) in Dibouka and Kouagna villages, central Gabon, in the context of hunter recollections of longer term trends since the 1950s. To control for changes in hunter behavior, such as trap location and characteristics, we report hunting offtake data per trap. Our results suggest the hunting area was already highly depleted by 2001; local hunters reported that 16 large-bodied prey species had become rare or locally extirpated over the last 60 years. Overall, we observed no significant declines in hunting offtake or changes in species composition from 2001 to 2010, and offtakes per trap increased slightly between 2004 and 2010. However, trapping distance from the villages increased, and there was a switch in hunting techniques; a larger proportion of the catch was hunted with guns in 2010. The number of hunters declined by 20% from 2004 to 2010, and male livelihood activities shifted away from hunting. Hunters with the lowest hunting incomes in 2004 were more likely than successful hunters to have moved away from the village by 2010 (often in response to alternative employment opportunities). Therefore, changes in trap success (potentially related to biological factors) were interacting with system-level changes in hunter number and composition (related to external socioeconomic factors) to produce a relatively static overall offtake. Our results highlight the importance of understanding the small-scale context of hunting to correctly interpret changes or apparent stasis in hunting effort and offtake over time.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Mamíferos/fisiologia , Animais , Ecossistema , Gabão , Modelos Lineares , Dinâmica Populacional , População Rural , Estações do Ano , Fatores Socioeconômicos , Fatores de Tempo
5.
Dtsch Med Wochenschr ; 137(10): 495, 2012 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-22374660

RESUMO

HISTORY AND ADMISSION FINDINGS: A 27-year-old male patient with a past medical history of HIV presented with acute myeloid leukemia for allogeneic hematopoietic stem cell transplantation (HSCT). Highly active anti-retroviral therapy suppressed the viral load below detection threshold. INVESTIGATIONS: There were no contraindications for allogeneic HSCT. TREATMENT AND COURSE: Myeloablative conditioning consisted of total body irradiation and cyclophosphamide. Anti-thymocyte globulin, tacrolimus and mycophenolate mofetil were used for immunosuppression. Combined anti-retroviral therapy (nucleoside and nucleotide analog reverse-transcriptase inhibitor, boostered protease inhibitor, maraviroc and raltegravir) was maintained for allogeneic HSCT and viral load remained below detection threshold. No graft-versus-host disease or serious infectious complications occurred. The patient showed good graft function with stable hematopoiesis. Localized Kaposi's sarcoma was diagnosed six months after allogeneic HSCT and treated successfully with surgical excision and reduction of immunosuppression. Almost one year after allogeneic HSCT, the CD4+ cell count is rising and viral load remains below detection threshold with combined anti-retroviral therapy. CONCLUSION: Allogeneic HSCT can be safely performed in HIV positive patients. Kaposi's sarcoma is a rare event after allogeneic HSCT and linked to strong immunosuppression.


Assuntos
Terapia Antirretroviral de Alta Atividade , Infecções por HIV/terapia , Leucemia Mieloide Aguda/terapia , Transplante de Células-Tronco , Adulto , Terapia Combinada , Infecções por HIV/complicações , Infecções por HIV/diagnóstico , Humanos , Leucemia Mieloide Aguda/diagnóstico , Masculino , Resultado do Tratamento
6.
Ann Oncol ; 16(8): 1326-33, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15919686

RESUMO

BACKGROUND: The current two studies evaluate the feasibility, toxicity and efficacy of an adjuvant combined modality treatment strategy containing a three to four-drug chemotherapy regimen plus 5-fluorouracil (FU)-based radiochemotherapy. PATIENTS AND METHODS: Between December 2000 and October 2003, a total of 86 patients were included in both studies. Patients with completely resected gastric adenocarcinoma including a D1 or D2 lymph node dissection (LND) were eligible. Treatment consisted of two cycles of folinic acid 500 mg/m2, 5-FU 2000 mg/m2 continuous infusion over 24 h once weekly for 6 consecutive weeks, paclitaxel 175 mg/m2 in weeks 1 and 4 and cisplatin 50 mg/m2 in weeks 2 and 5 (FLPP; n=41) or two cycles of the same 5-FU/folinic acid schedule but with cisplatin 50 mg/m2 only in weeks 1, 3 and 5 (FLP; n=45). Radiation with 45 Gy plus concomitantly applied 5-FU 225 mg/m2/24 h was scheduled in between the two cycles. RESULTS: Patients characteristics were: D1/D2 LND FLP group 53%/42%; FLPP group 27%/68%; stage distribution: UICC stages III/IV(M0) FLP group 63% and FLPP group 66%. Median follow-up was 10 months (3-25) for FLP and 18 months (2-51) for FLPP patients. CTC grade 3/4 toxicities during the first cycle/chemoradiation/second cycle of FLP: granulocytopenia 3%/0/27%, anorexia 6%/10%/8%; diarrhea 8%/0/4%, nausea 3%/0/4%; FLPP: granulocytopenia 0/0/37%, anorexia 5%/11%/6%; diarrhea 5%/0/3, nausea 3%/8%/0%; early death in one patient due to Pneumocystis carinii pneumonia. Projected 2-year progression-free survival was 64% (95% CI 56% to 68%) for the FLP and 61% (95% CI 42% to 78%) for the FLPP group. CONCLUSIONS: Both chemoradiation regimens appear feasible with an acceptable toxicity profile indicating that cisplatin can be added to 5-FU/FA and that even a four-drug regimen can be investigated further in prospective clinical trials in completely resected gastric cancer patients. Treatment should be given in experienced centres in order to avoid unnecessary toxicity.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/radioterapia , Adenocarcinoma/secundário , Adolescente , Adulto , Idoso , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Terapia Combinada , Estudos de Viabilidade , Feminino , Fluoruracila/administração & dosagem , Humanos , Leucovorina/administração & dosagem , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Radioterapia Adjuvante , Fatores de Risco , Neoplasias Gástricas/patologia , Taxa de Sobrevida
7.
J Cancer Res Clin Oncol ; 131(4): 255-60, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15627215

RESUMO

PURPOSE: We investigated the incidence of secondary leukemia in patients treated with first-line high-dose chemotherapy (HDCT) plus autologous stem cell transplantation (PBSCT) for advanced testicular cancer. METHODS: Three hundred and twenty-three patients who were entered into two consecutive prospective Phase-II studies of the German Testicular Cancer Study Group were analyzed. A total of 221 patients had received HD-VIP containing cisplatin, ifosfamide, and etoposide and 102 patients were treated with Tax-HD-VIP containing cisplatin, ifosfamide, etoposide, and paclitaxel, each cycle supported by autologous PBSCT. RESULTS: Patients had received a median cumulative etoposide dose of 4.9 g/m(2) (range, 2.2-9.4 g/m(2)). The median follow-up duration for all patients was 36 months (range, 0-128) with a median follow up time of 50 months (range, 0-128) for patients surviving at least 1 year after therapy. One patient developed a secondary acute myeloid leukemia (s-AML) involving a chromosomal translocation t(11;19)(q23;p13.3) 24 months after the start of chemotherapy resulting in a cumulative incidence of 0.48% [95% confidence interval (CI) 0-1.42]. Additionally, two patients with primary mediastinal germ cell cancer developed a myelodysplastic syndrome. No solid tumors had occurred. CONCLUSIONS: HDCT including high-dose etoposide with autologous PBSCT as first-line therapy for advanced testicular cancer was associated with an acceptably low risk of developing secondary leukemia.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Germinoma/tratamento farmacológico , Leucemia Mieloide Aguda/induzido quimicamente , Segunda Neoplasia Primária/induzido quimicamente , Neoplasias Testiculares/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Cisplatino/efeitos adversos , Ensaios Clínicos Fase II como Assunto , Etoposídeo/efeitos adversos , Seguimentos , Alemanha , Germinoma/cirurgia , Humanos , Ifosfamida/efeitos adversos , Masculino , Neoplasias do Mediastino/tratamento farmacológico , Estudos Multicêntricos como Assunto , Síndromes Mielodisplásicas/induzido quimicamente , Paclitaxel/efeitos adversos , Transplante de Células-Tronco de Sangue Periférico , Neoplasias Testiculares/cirurgia , Translocação Genética/efeitos dos fármacos , Transplante Autólogo
8.
J Clin Oncol ; 21(22): 4083-91, 2003 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-14568987

RESUMO

PURPOSE: Patients with disseminated germ cell cancer and poor prognosis (International Germ Cell Cancer Collaborative Group [IGCCCG] classification) achieve only a 45% to 50% long-term survival by standard chemotherapy. First-line high-dose chemotherapy might be able to improve the result. This analysis reports toxicity and long-term results of a large phase I/II study of sequential high-dose etoposide, ifosfamide, and cisplatin (VIP) in patients with advanced germ cell tumors. PATIENTS AND METHODS: Between July 1993 and November 1999, 221 patients with either Indiana "advanced disease" (n = 39) or IGCCCG "poor prognosis" criteria (n = 182) received one cycle of VIP followed by three to four sequential cycles of high-dose VIP chemotherapy plus stem cell support, every 3 weeks, at six consecutive dose levels. RESULTS: Dose limiting toxicity occurred at level 8 (100 mg/m2 cisplatinum, 1750 mg/m2 etoposide, 12 g/m2 ifosfamide) with grade 4 mucositis (three of eight patients), grade 3 CNS toxicity (one of eight patients), grade 4 renal toxicity (one of eight patients), and prolonged granulocytopenia (one of eight patients). After 4-year median follow-up, progression-free survival and disease-specific survival rates in the poor prognosis subgroup were 69% and 79% at 2 years and 68% and 73% at 5 years, with 76% for gonadal/retroperitoneal versus 67% for mediastinal primaries. Severe toxicity included treatment related death (4%), treatment-related acute myeloid leukemia (1%), long-term impared renal function (3%), chronic renal failure (1%), and persistent grade 2-3 neuropathy (5%). CONCLUSION: Repetitive cycles of high-dose VIP with peripheral stem cell support can be successfully applied in a multicenter setting. Dose level 6 with cisplatin 100 mg/m2, etoposide 1500 mg/m2, and ifosfamide 10 g/m2 is recommended for further investigation in randomized trials. An ongoing randomized trial within the European Organization for Research and Treatment of Cancer evaluates this protocol against four cycles of standard cisplatin, etoposide, and bleomycin.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Cisplatino/administração & dosagem , Etoposídeo/administração & dosagem , Germinoma/terapia , Transplante de Células-Tronco Hematopoéticas , Ifosfamida/administração & dosagem , Neoplasias Testiculares/terapia , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/efeitos adversos , Terapia Combinada , Intervalo Livre de Doença , Etoposídeo/efeitos adversos , Germinoma/mortalidade , Germinoma/secundário , Humanos , Ifosfamida/efeitos adversos , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Neoplasias Testiculares/mortalidade , Neoplasias Testiculares/patologia , Fatores de Tempo , Transplante Autólogo , Resultado do Tratamento
9.
Br J Cancer ; 87(10): 1066-71, 2002 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-12402143

RESUMO

First-line sequential high dose chemotherapy is under investigation in patients with "poor prognosis" metastatic germ cell tumours in order to improve survival. Despite the use of autologous peripheral blood stem cell transplantation and granulocyte colony stimulating factor chemotherapy dose intensification is associated with severe haematotoxicity including anaemia, which may significantly affect quality of life and tolerability of chemotherapy. This study investigates the frequency and degree of anaemia in patients receiving first-line sequential high dose chemotherapy for metastatic testicular cancer and the impact of anaemia on treatment outcome. A total of 101 newly diagnosed patients with "poor prognosis" metastatic nonseminomatous germ cell tumours were treated with one cycle of standard VIP followed by three cycles of HD-VIP-chemotherapy (etoposide, ifosfamide, cisplatin) within a large phase I/II study. Differential blood cell counts were taken prior, during and after every cycle of chemotherapy. Additionally, the numbers of red blood cell and platelet transfusions were recorded. Kaplan-Meier analyses were performed to correlate pre-treatment and post-treatment haemoglobin values to response and overall survival. Forty-eight per cent of the patients were classified anaemic (haemoglobin <12 g dl(-1)) prior to the start of chemotherapy. The application of sequential HD-VIP resulted in median haemoglobin nadirs between 7.8 g dl(-1) (range 5.5-11.1 g dl(-1)) in the first cycle and 7.6 g dl(-1) (range 6.0-11.4 g dl(-1)) in the third cycle despite the frequent use of red blood cell transfusions. Almost all patients (99%) had haemoglobin levels <10 g dl(-1) at some timepoint during first-line sequential high dose chemotherapy. Overall, 97 patients received red blood cell transfusions with a median of 10 units (range 2-25) per patient during the four consecutive cycles of therapy. The time to first transfusion was shortest in patients with the lowest initial haemoglobin values. While there was no prediction of response or outcome by baseline haemoglobin-levels, a significant survival difference in favour of patients with a haemoglobin value >10.5 g dl(-1) after completion of four cycles of therapy (at leukocyte recovery after the last cycle) compared to those with haemoglobin values <10.5 g dl(-1) was found with 3-year overall survival rates of 87% vs 68%, respectively (P<0.05). Severe anaemia is a very frequent side effect of sequential dose intensive therapy in patients with germ cell cancer, with almost all patients becoming transfusion dependent. Despite the frequent use of red blood cell transfusions, median haemoglobin nadirs remained about 7.5-8 g dl(-1) during therapy. A correlation of haemoglobin-values after completion of therapy to overall treatment outcome was found.


Assuntos
Anemia/induzido quimicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Germinoma/tratamento farmacológico , Neoplasias Testiculares/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Germinoma/sangue , Germinoma/mortalidade , Hemoglobinas/análise , Humanos , Masculino , Metástase Neoplásica , Transplante de Células-Tronco de Sangue Periférico , Neoplasias Testiculares/sangue , Neoplasias Testiculares/mortalidade , Trombocitopenia/induzido quimicamente , Transplante Autólogo
10.
Ann Oncol ; 12(8): 1151-5, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11583199

RESUMO

BACKGROUND: We assessed the efficacy of amifostine for protection from chemotherapy-induced toxicities in patients treated with conventional-dose paclitaxel, ifosfamide, cisplatin (TIP) and high-dose carboplatin, etoposide and thiotepa (CET) followed by peripheral blood progenitor cell (PBPC) rescue. PATIENTS AND METHODS: In a prospective single-center study 40 patients with relapsed or refractory germ-cell tumors (GCT) were treated with 3 cycles of conventional-dose TIP followed by one cycle of high-dose CET. Patients were randomized either to receive one fixed dose of 500 mg amifostine per day of conventional-dose TIP and two fixed doses of 500 mg per day amifostine during high-dose CET (group A, n = 20) or no amifostine (group B, n = 20). Prior to the first cycle of TIP, one course of 175 mg/m2 paclitaxel and 5 g/m2 ifosfamide (TI) followed by granulocyte-colony stimulating factor (G-CSF) at 10 microg/kg/day were given for PBPC mobilization. RESULTS: Toxicities and response to conventional-dose TIP and high-dose CET could be evaluated in 40 patients (100%) and 32 of 40 patients (80%), respectively. Peripheral neurotoxicity (i.e. paresthesia or sensorymotor impairment), hearing impairment, hematologic toxicity, nephrotoxicity, nausea, myalgia, skin- and liver-toxicity did not differ siginificantly between the two patient groups. Likewise, the response rates to TIP and high-dose CET were comparable in patients with or without amifostine. After a median follow-up of 18 months, 8 of 20 (40%) patients of group A and 6 of 20 (30%) patients of group B are without relapse. CONCLUSION: Repeated low doses of 500 mg amifostine additional to conventional-dose TIP or high-dose CET showed no unequivocal advantage in protection from treatment-related toxicities. Furthermore, no significant differences in response rates or survival could be observed in this small number of patients.


Assuntos
Amifostina/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Protetores contra Radiação/uso terapêutico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/farmacologia , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/imunologia , Humanos , Ifosfamida/administração & dosagem , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Estudos Prospectivos , Taxoides
11.
J Clin Oncol ; 19(12): 3029-36, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11408498

RESUMO

PURPOSE: High-dose chemotherapy (HD-Ctx) followed by autologous peripheral-blood stem-cell (PBSC) transplantation is currently investigated in patients with poor prognosis or relapsed metastatic germ cell tumor (GCTs). This study analyzed the presence and the clinical importance of contaminating tumor cells in PBSC preparations used to support HD-Ctx in GCT patients. PATIENTS AND METHODS: Seven targets for reverse transcription polymerase chain reaction (RT-PCR)-based detection of GCT cells were able to detect seminomatous and different histologic variants of nonseminomatous tumor cells. PBSC preparations from 57 patients were investigated for the presence of contaminating tumor cells using this set of targets, including beta human chorionic gonadotropin (beta-hCG), fibronectin (EDB variant), epidermal growth factor receptor (EGFR), CD44 (v8 to 10 variant), germ cell and placental alkaline phosphatase (AP), human endogenous retrovirus type K (ENV and GAG), and XIST. Samples of PBSC preparations from four healthy donors for allogenic transplantations as well as blood specimens from 10 healthy volunteers served as negative controls. RESULTS: Fifty patients (43 first-line and seven second-line Ctx) were assessable. Combining all RT-PCR results, 29 PBSC preparations (58%) were positive for tumor-specific amplification products (HERV-K 0, fibronectin 4, XIST 14, beta-hCG 19, AP 19, CD44 24, EGFR 26). Ten (35%) of 29 patients who underwent transplantation with positive PBSC preparations and seven (33%) of 21 patients with negative PBSC preparations have suffered relapse or progression (not significant [ns]). With a median follow-up of 22 months (2 to 66) post-HD-Ctx projected 3-year survival rates are 68% (RT-PCR+) and 58% (RT-PCR-) (ns). None of the 10 control peripheral-blood samples showed positivity for any of the targets studied. CONCLUSION: GCT cells can be detected in more than 50% of PBSC preparations using a RT-PCR approach with multiple targets. Despite the presence of tumor cells, retransplantation of the PBSC products did not effect long-term outcome. Factors such as responsiveness to chemotherapy and tumor mass seem to overcome the importance of potentially re-infused tumor cells.


Assuntos
Germinoma/terapia , Transplante de Células-Tronco Hematopoéticas , Leucaférese , Células Neoplásicas Circulantes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adolescente , Adulto , Biomarcadores Tumorais , Estudos de Casos e Controles , Primers do DNA , Intervalo Livre de Doença , Seguimentos , Germinoma/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Taxa de Sobrevida
12.
Transfusion ; 41(2): 196-200, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11239222

RESUMO

BACKGROUND: The impact of amifostine on PBPC mobilization with paclitaxel and ifosfamide plus G-CSF was assessed. STUDY DESIGN AND METHODS: Forty patients with a median age of 34 years (range, 19-53) who had germ cell tumor were evaluated for high-dose chemotherapy. Patients were randomly assigned to receive either a single 500-mg dose of amifostine (Group A, n = 20) or no amifostine (Group B, n = 20) before mobilization chemotherapy with paclitaxel (175 mg/m(2)) given over 3 hours and ifosfamide (5 g/m(2)) given over 24 hours (TI) on Day 1. G-CSF at 10 microg per kg per day was given subsequent to TI with or without amifostine from Day 3 until the end of leukapheresis procedures. RESULTS: In 2 (10%) of 20 patients receiving amifostine and 3 (15%) of 20 patients not receiving it, no PBPC separation was performed because of mobilization failure. No significant differences were observed in the study arms with regard to the time from chemotherapy until first PBPC collection or the number of apheresis procedures needed to harvest more than 2.5 x 10(6) CD34+ cells per kg. Furthermore, leukapheresis procedures yielded comparable doses of CD34+ cells per kg (3.4 x 10(6) vs. 3.6 x 10(6); p = 0.82), MNCs per kg (2.7 x 10(8) vs. 2.6 x 10(8); p = 0.18), and CFU-GM per kg (15.9 x 10(4) vs. 19.3 x 10(4); p = 0.20). Patients in Group A had higher numbers of circulating CD34+ cells on Day 10 (103.0/microL vs. 46.8/microL; p = 0.10) and on Day 11 (63.0/microL vs.14.3/microL; p = 0.04) than did patients in Group B. CONCLUSION: Administration of a single dose of amifostine before chemotherapy with TI mobilized higher numbers of CD34 cells in the circulation, but did not enhance the overall collection efficiency in the present trial.


Assuntos
Amifostina/farmacologia , Fator Estimulador de Colônias de Granulócitos/farmacologia , Mobilização de Células-Tronco Hematopoéticas , Ifosfamida/farmacologia , Paclitaxel/farmacologia , Adulto , Amifostina/administração & dosagem , Antígenos CD34/sangue , Coleta de Amostras Sanguíneas , Relação Dose-Resposta a Droga , Células-Tronco Hematopoéticas/imunologia , Humanos , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Projetos Piloto , Estudos Prospectivos
13.
Neuroreport ; 10(3): 635-8, 1999 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-10208603

RESUMO

Increasing evidence implicates apoptosis as a major mechanism of cell death in neurodegenerative diseases. Recent evidence has demonstrated that chronic administration of MPTP can lead to apoptotic cell death. In the present study we examined whether transgenic mice expressing a dominant negative inhibitor of interleukin-1beta convertase enzyme (ICE) are resistant to MPTP induced neurotoxicity. MPTP resulted in a significant depletion of dopamine, DOPAC and HVA in littermate control mice which were completely inhibited in the mutant interleukin-1beta converting enzyme mice. There was also significant protection against MPTP-induced depletion of tyrosine hydroxylase-immunoreactive neurons. There was no alteration in MPTP uptake or metabolism. These results provide further evidence that apoptotic cell death as well as ICE may play an important role in the neurotoxicity of MPTP.


Assuntos
Caspase 1/genética , Expressão Gênica/fisiologia , Genes Dominantes , Intoxicação por MPTP , Camundongos Transgênicos/genética , Mutação/genética , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Dopamina/metabolismo , Resistência a Medicamentos/genética , Ácido Homovanílico/metabolismo , Camundongos , Valores de Referência
15.
Bone Marrow Transplant ; 22(6): 579-83, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9758347

RESUMO

Donor lymphocyte infusions (DLI) are an effective treatment of leukemia relapse after allogeneic bone marrow transplantation. Undesired side-effects are the development of graft-versus-host disease (GVHD) and the occurrence of pancytopenia in some patients. In a pilot study, we investigated if unmanipulated G-CSF-mobilized peripheral blood stem cells which naturally contain large numbers of T lymphocytes (D-PBSC/LI) would be equally effective or even superior than DLI in generating a graft-versus-leukemia reaction (GVL) but could mitigate or prevent the development of pancytopenia. We treated 12 patients with CML chronic phase (n = 5), CML blast crisis (n = 2), AML (n = 2), ALL (n = 1), CLL (n = 1) and multiple myeloma (n = 1). In five patients with acute leukemia or CML blast crisis D-PBSC/LI followed intensive chemotherapy (group A), in seven patients D-PBSC/LI were given without any prior chemotherapy (group B). In group A two patients were evaluable for hematologic toxicity. Leukopenia <1000/microl lasted for 10 and 19 days, and thrombocytopenia <20,000/microl for 11 and 13 days, respectively. In group B leukopenia <1000/microl and thrombocytopenia <20,000/microl was observed in only one patient. Moderate cytopenia developed in four of five evaluable patients. A complete remission could be achieved in all seven patients with CML who all developed acute and/or chronic GVHD. None of the remaining five patients achieved a complete remission despite acute and/or chronic GVHD in two of them. Four patients died from disease progression, one patient from a secondary lymphoma, and one patient as a result of uncontrolled GVHD. In conclusion, D-PBSC/LI is effective in inducing GVL reaction but it does not prevent pancytopenia in each case. It remains unclear if it mitigates the incidence and severity of pancytopenia.


Assuntos
Transplante de Medula Óssea , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Mobilização de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas , Leucemia/terapia , Adulto , Transplante de Medula Óssea/efeitos adversos , Intervalo Livre de Doença , Feminino , Doença Enxerto-Hospedeiro/etiologia , Efeito Enxerto vs Tumor , Humanos , Masculino , Pessoa de Meia-Idade , Pancitopenia/prevenção & controle , Recidiva , Linfócitos T/transplante , Doadores de Tecidos , Transplante Homólogo
16.
Bone Marrow Transplant ; 21(9): 863-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9613776

RESUMO

We investigated peripheral blood progenitor cell (PBPC) mobilization by disease-specific chemotherapy in patients with metastatic soft tissue sarcoma (STS). Nine patients, five females and four males, aged 12-51 years, pretreated by one to nine courses of cytotoxic chemotherapy, underwent STS-specific mobilization followed by G-CSF at 5 microg/kg/day. PBPC were collected by 19 conventional-volume aphereses (8-12 l) with one to four procedures in individual patients. Leukaphereses started on median day 15 (range 13-18) from the first day of mobilization chemotherapy at medians of 25.8 x 10(3) WBC/microl (6.8-46.9), 3.5 x 10(3) MNC/microl (1.1-8.8), 122 x 10(3) platelets/microl (72-293) and 30.7 CD34+ cells/microl (6.7-207.8). Cumulative harvests resulted in medians of 4.6 x 10(8) MNC/kg (3.0-6.4), 2.9 x 10(6) CD34+ cells/kg (1.1-11.1) and 12.0 x 10(4) CFU-GM/kg (2.0-37.8). Eight patients underwent high-dose chemotherapy (HDCT) followed by PBPC rescue. Seven patients recovered hematopoiesis at medians of 12 days (8-15) for ANC >0.5 x 10(3)/microl and 14 days (8-27) for platelets >20 x 10(3)/microl. One patient, who received 1.6 x 10(6) CD34+ cells/kg, exhibited delayed ANC recovery on day +37 and failed to recover platelets until hospital discharge on day +55. We conclude that in patients with metastatic STS, who are pretreated by standard chemotherapy, PBPC can be mobilized by a further course of STS-specific chemotherapy plus G-CSF. One to four conventional-volume aphereses result in PBPC autografts that can serve as hematopoietic rescue for patients scheduled for HDCT.


Assuntos
Mobilização de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/efeitos dos fármacos , Sarcoma/tratamento farmacológico , Sarcoma/terapia , Neoplasias de Tecidos Moles/tratamento farmacológico , Neoplasias de Tecidos Moles/terapia , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Terapia Combinada , Feminino , Sobrevivência de Enxerto , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Hematopoese , Humanos , Leucaférese , Masculino , Pessoa de Meia-Idade , Sarcoma/sangue , Neoplasias de Tecidos Moles/sangue
17.
Eur J Cancer ; 34(12): 1883-8, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10023310

RESUMO

High-dose chemotherapy (HDCT) has evolved as a strategy to improve the treatment outcome in patients with relapsed and/or refractory germ cell tumours. Between August 1989 and September 1995, 150 consecutive patients with relapsed and/or refractory germ cell tumours were treated with conventional-dose salvage chemotherapy followed by one cycle of HDCT with carboplatin 1500-2000 mg/m2, etoposide 1200-2400 mg/m2 and ifosfamide 0-10 g/m2 and were retrospectively analysed. With a median follow-up time of 55 months (range 21-88 months) 51/150 (34%) patients are alive and disease free. The projected event-free and overall survival are 29% (confidence interval 22-37%) and 39% (confidence interval 31-47%) respectively. The relevance of prognostic variables for long-term survival after HDCT were prospectively confirmed. Persisting toxicities occurred in approximately one third of the long-term survivors. Treatment intensification with HDCT resulted in a significant proportion of the long-term survivors in patients with relapsed and/or refractory germ cell tumours. Trials to prospectively evaluate HDCT as an early intervention in these patients seem justified.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Mediastino/tratamento farmacológico , Neoplasias Retroperitoneais/tratamento farmacológico , Seminoma/tratamento farmacológico , Neoplasias Testiculares/tratamento farmacológico , Adolescente , Adulto , Carboplatina/administração & dosagem , Intervalo Livre de Doença , Etoposídeo/administração & dosagem , Feminino , Seguimentos , Transplante de Células-Tronco Hematopoéticas , Humanos , Ifosfamida/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Terapia de Salvação , Resultado do Tratamento
18.
J Clin Pathol ; 51(12): 886-90, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10070328

RESUMO

AIMS: To determine the frequency of immature haemopoietic cells in the peripheral blood of healthy persons. METHODS: Cytocentrifuge preparations were made using mononuclear leucocytes separated by a Ficoll-Hypaque density gradient. The slides were stained by May-Grünwald-Giemsa. The combination with immunoperoxidase technique allowed immunotyping of uncommon blood cells. RESULTS: Blast cells expressing the progenitor cell marker CD34 represented 0.11 (0.06) per cent (mean (SD)) of the total mononuclear leucocyte count; these were the haemopoietic progenitor cells in the peripheral blood. Dark blue cells expressing CD38, CD45, HLA-DR, CD4, CD11a, CD29, CD49d, CD50, and CD54 represented 0.30 (0.21) per cent of the mononuclear leucocytes; most of these cells did not express T, B, NK, myelomonocytic, progenitor cell, proliferation, activation, blood dendritic cell, or follicular dendritic cell markers. These were dendritic cell precursors in the peripheral blood. Very small numbers of cells expressing CD83 were found. Blast-like cells expressing CD45, HLA-DR, CD11a, and CD50 represented 0.15 (0.10) per cent of the mononuclear leucocytes; morphology and immunotyping supported the conclusion that these cells were poorly differentiated monocytes. CONCLUSIONS: Morphological investigation of mononuclear leucocytes in peripheral blood of healthy persons can be used to detect small numbers of blasts, dark blue cells, and blast-like cells. The immunoperoxidase technique can then be used for immunotyping of these cells. This simple method may be helpful in diagnosing haematological disorders.


Assuntos
Antígenos CD/análise , Células-Tronco Hematopoéticas/citologia , Leucócitos Mononucleares/citologia , Adulto , Antígenos CD34/análise , Biomarcadores/análise , Corantes , Células Dendríticas/imunologia , Amarelo de Eosina-(YS) , Células-Tronco Hematopoéticas/imunologia , Humanos , Imunoglobulinas/análise , Imunofenotipagem , Leucócitos Mononucleares/imunologia , Glicoproteínas de Membrana/análise , Azul de Metileno , Antígeno CD83
19.
Cancer ; 79(1): 161-8, 1997 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-8988741

RESUMO

BACKGROUND: The optimal treatment of patients with recurrent or refractory germ cell tumors is still a debated topic. High dose chemotherapy (HDCT) with autologous stem cell rescue (ASCR) might be promising for intensification of first or subsequent salvage treatment. However, the long-term results of this approach remain largely unknown. METHODS: Between August 1989 and September 1992, 74 patients with recurrent and/or refractory germ cell tumors were treated in a Phase I/II trial with HDCT consisting of carboplatin (1500-2000 mg/m2), etoposide (1200-2400 mg/m2), and ifosfamide (0-10 g/m2). In September 1995 all patients were reevaluated to determine overall response, late toxicities, and survival. RESULTS: Two patients died from treatment-related toxicity shortly after HDCT, and 47 had recurrence or progression of disease after a median of 3 months (range, 1-44 months). Of these latter patients, three were living continuously disease free at the conclusion of this study after a second HDCT regimen, salvage surgery, or chronic oral etoposide treatment. The results were an overall survival of 38% (95% confidence interval, 27-50%) and a failure free survival of 31% (95% confidence interval, 21-43%) at 5 years. There were no long-term survivors among patients whose disease progressed while they were receiving conventional doses of cisplatin before HDCT. Late toxicities consisted mainly or renal impairment (in 21% of patients), paresthesias (in 29%), and ototoxicity (in 18%). CONCLUSIONS: HDCT can be curative for patients with germ cell tumors who do not become disease free after conventional dose chemotherapy but respond to this treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Germinoma/tratamento farmacológico , Neoplasias do Mediastino/tratamento farmacológico , Neoplasias Retroperitoneais/tratamento farmacológico , Neoplasias Testiculares/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Intervalo Livre de Doença , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Seguimentos , Germinoma/mortalidade , Humanos , Ifosfamida/administração & dosagem , Ifosfamida/efeitos adversos , Masculino , Neoplasias do Mediastino/mortalidade , Pessoa de Meia-Idade , Neoplasias Retroperitoneais/mortalidade , Terapia de Salvação , Sobreviventes , Neoplasias Testiculares/mortalidade
20.
Ann Hematol ; 72(3): 125-9, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8766253

RESUMO

The diagnostic potential of immunocytochemical investigation of human bone marrow has not been fully realized due to difficulties in morphological identifying of immunostained cells. We used an indirect immunoperoxidase technique after May-Grünwald-Giemsa staining for simultaneous morphological and immunocytochemical analysis of blasts in human bone marrow. Six healthy bone marrow donors were investigated. Most blasts I expressed CD34, CD38 and HLA-DR. Expression of c-kit (CD117) was observed on 42 +/- 9% of blasts I. Granulocytomonocytopoietic character was demonstrated by expression of CD13 (33 +/- 15%) and CD45RA (23 +/- 10%) and erythropoietic character was demonstrated by expression of CD36 (22 +/- 8%) and CD45RO (30 +/- 11%). A very low proportion of blasts I were Thy-1 and CD61 positive; 34 +/- 6% of blasts I expressed CD22, representing B lymphoid committed progenitors. CD3, CD15, and glycophorin A expression was not detected. Blasts II and III and proerythroblasts did not show CD34 positivity. We conclude that blasts I are morphologically identifiable cells with a high percentage of CD34, CD38, and HLA-DR positivity. They are a pool of committed progenitor cells for erythropoiesis, granulocytomonocytopoiesis, megakaryocytopoiesis, and B cell development. Blast II and proerythroblast represent the first morphologically identifiable cells of granulocytopoiesis and erythropoiesis.


Assuntos
Células da Medula Óssea , Medula Óssea/imunologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/imunologia , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Antígenos CD/análise , Antígenos CD34/análise , Antígenos de Diferenciação/análise , Medula Óssea/química , Antígenos HLA-DR/análise , Células-Tronco Hematopoéticas/química , Humanos , Técnicas Imunoenzimáticas , Glicoproteínas de Membrana , N-Glicosil Hidrolases/análise , Proteínas Proto-Oncogênicas c-kit/análise
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