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1.
J Phys Condens Matter ; 27(48): 485401, 2015 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-26569574

RESUMO

We report inelastic neutron scattering (INS) measurements on the polycrystalline oP60-type clathrate BaGe5, whose crystal structure is related to the type-I clathrate Ba8Ge43□3 and to the cP124-clathrate Ba6Ge25. Our results show that BaGe5 exhibits a similar phonon density of states (PDOS) in the energy range 0-40 meV with respect to Ba8Ge43□3. The low-energy region of the PDOS spectrum (0-10 meV) consists of two peaks at 4.1 and 6.2 meV likely related to Ba-weighted modes. Compared to Ba8Ge43□3, the low-energy region of the phonon spectrum of BaGe5 shows a more complex structure, likely reflecting the presence of three distinct crystallographic sites for Ba. The specific heat data of BaGe5, reexamined in light of the INS results, indicate that the Ba-weighted modes dominate the low-temperature behavior of Cp.

2.
Dalton Trans ; 44(16): 7524-37, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25805335

RESUMO

We present the evolution of the low-temperature thermodynamic, galvanomagnetic and thermoelectric properties of the type-I clathrate Ba8Ni(x)Ge(46-x-y□y) with the Ni concentration studied on polycrystalline samples with 0.0 ≤ x ≤ 6.0 by means of specific heat, Hall effect, electrical resistivity, thermopower and thermal conductivity measurements in the 2-350 K temperature range and supported by first-principles calculations. The experimental results evidence a 2a × 2a × 2a supercell described in the space group Ia3d for x ≤ 1.0 and a primitive unit cell a × a × a (space group Pm3n) above this Ni content. This concentration also marks the limit between a regime where both electrons and holes contribute to the electrical conduction (x ≤ 1.0) and a conventional, single-carrier regime (x > 1.0). This evolution is traced by the variations in the thermopower and Hall effect with x. In agreement with band structure calculations, increasing the Ni content drives the system from a nearly-compensated semimetallic state (x = 0.0) towards a narrow-band-gap semiconducting state (x = 4.0). A crossover from an n-type to a p-type conduction occurs when crossing the x = 4.0 concentration i.e. for x = 4.1. The solid solution Ba8Ni(x)Ge(46-x-y□y) therefore provides an excellent experimental platform to probe the evolution of the peculiar properties of the parent type-I clathrate Ba8Ge43□3 upon Ge/Ni substitution and filling up of the vacancies, which might be universal among the ternary systems at low substitution levels.

3.
J Phys Condens Matter ; 26(48): 485801, 2014 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-25373324

RESUMO

Polycrystalline samples of the type-I clathrate Ba(8)Ni(x)Ge(46-x-y)□(y) were synthesized for 0.2 ⩽ x ⩽ 3.5 by melt quenching and for 3.5

4.
Inorg Chem ; 51(8): 4730-41, 2012 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-22455546

RESUMO

Type-I clathrate phase Ba(8)Ni(x)□(y)Si(46-x-y) (□ = vacancy) was obtained from the elements at 1000 °C with the homogeneity range 2.4 ≤ x ≤ 3.8 and 0 ≤ y ≤ 0.9. In addition, samples with low Ni content (x = 1.4 and 1.6; y = 0) and small Ba deficiency were prepared from the melt by steel-quenching. Compositions were established by microprobe analysis and crystal structure determination. Ba(8-δ)Ni(x)□(y)Si(46-x-y) crystallizes in the space group Pm ̅3n (No. 223) with lattice parameter ranging from a = 10.3088(1) Å for Ba(7.9(1))Ni(1.4(1))Si(44.6(1)) to a = 10.2896(1) Å for Ba(8.00(3))Ni(3.82(4))Si(41.33(6)). Single-crystal X-ray diffraction data together with microprobe analysis indicate an increasing number of framework vacancies toward compositions with higher Ni content. For all compositions investigated, Ni K-edge X-ray absorption spectroscopy measurements showed an electronic state close to that of elemental Ni. All samples exhibit metallic-like behavior with moderate thermopower and low thermal conductivity in the temperature range 300-773 K. Samples with compositions Ba(7.9(1))Ni(1.4(1))Si(44.6(1)) and Ba(7.9(1))Ni(1.6(1))Si(44.4(1)) are superconducting with T(c) values of 6.0 and 5.5 K, respectively.

5.
Dalton Trans ; 39(4): 1078-88, 2010 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-20066194

RESUMO

The single phase clathrate-I Ba(8)Ge(43)square(3) (space group Ia3d (no. 230), a = 21.307(1) A) was synthesized by quenching the melt between cold steel plates. Specimens for physical property measurements were characterized by microstructure analysis and X-ray diffraction on polycrystalline samples as well as single crystals. Transport properties including thermopower, electrical resistivity, thermal conductivity and specific heat were investigated in a temperature range of 2-673 K. The electrical resistivity exhibits a metal-like temperature dependence below 300 K turning into a semiconductor-like behaviour above 300 K. The analysis of the specific heat at low temperature indicates a finite density of states at the Fermi level, thus corroborating the metallic character below 300 K. The temperature dependence of the specific heat was modelled assuming Einstein-like localized vibrations of Ba atoms inside the cages of the Ge framework. A conventional crystal-like behaviour of the thermal conductivity with a low lattice contribution (kappa(l)(300 K) = 2.7 W m(-1) K(-1)) has been evidenced.

6.
Dalton Trans ; 39(4): 1071-7, 2010 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-20066193

RESUMO

Single crystals of the type-I clathrate Ba(8)Ni(3.5)Ge(42.1)square(0.4) (space group Pm3n, no. 223, a = 10.798(2) A, l = 30 mm, slashed circle = 8 mm) were grown from the melt using the Bridgman technique. Their composition, determined by microprobe analysis, reveals a distinctly lower Ni content than previously reported for the lower limit (x = 5.4) of the homogeneity range of the clathrate-I phase Ba(8)Ni(x)Ge(46-x). From single crystal X-ray diffraction data we introduce a crystal structure model that takes point defects (vacancies) square in the Ge network into account. It reveals that both Ni and square accumulate at a single site (6c) and that, as a consequence, the Ge network distorts considerably. Ba(8)Ni(3.5)Ge(42.1)square(0.4) shows metal-like behaviour (drho/dT > 0) albeit with high resistivity at room temperature (rho(300 K) approximately 1 mOmega cm). Together with the low charge carrier concentration of 2.3 e(-)/unit cell at 300 K this is typical of a degenerate semiconductor. The lattice thermal conductivity is distinctly smaller than that of Ba(8)Ge(43)square(3), where the vacancies partially order, and smaller than those of Ba-Ni-Ge type-I clathrates without vacancies, suggesting that disordered vacancies efficiently scatter heat-transporting phonons. We provide evidence that the maximum value of the thermoelectric figure of merit reached in Ba(8)Ni(3.5)Ge(42.1)square(0.4), ZT(680 K) congruent with 0.21, can be further improved by adjusting the charge carrier concentration.

7.
Onkologie ; 26(1): 38-43, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12624516

RESUMO

BACKGROUND: The prognosis for patients with malignant astrocytoma or brain metastases is often fatal despite intensive therapy. Therefore we wished to elucidate whether the quality of life (QoL) is a determinant of overall survival (OAS). PATIENTS AND METHODS: From 1997 to 2000 153 patients with brain tumours were screened; 39 patients (26%) refused to participate and further 47 patients were excluded (cerebral impairment 14%, amaurosis/ language problems 3%, Karnofsky performance score < 50% 7%, death 8%, non-compliance 7%). Thus, 57 patients were analysed (33 with primary brain tumours, 24 with brain metastases). With the FACT-G questionnaire cancer-specific aspects of health-related QoL were assessed. RESULTS: Patients with metastases showed a lower QoL in the physical sphere than patients with astrocytoma, but there were no significant differences in OAS. Median survival of patients with good QoL was 31.3 months versus 14.2 months in patients with bad QoL. Only the two variables 'living with a spouse' and FACT-G sum score had a statistically significant influence on survival (p = 0.033 and p = 0.003) modelled by the Cox-PH regression. Patients who did not live with a spouse had shorter survival times than the other patients. CONCLUSION: Health-related QoL can serve to identify a patient group with higher risks of death.


Assuntos
Astrocitoma/radioterapia , Neoplasias Encefálicas/radioterapia , Irradiação Craniana , Glioblastoma/radioterapia , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Astrocitoma/mortalidade , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Feminino , Seguimentos , Glioblastoma/mortalidade , Humanos , Masculino , Estado Civil , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Prognóstico , Radioterapia Adjuvante , Análise de Regressão , Medição de Risco , Taxa de Sobrevida
8.
Onkologie ; 26(6): 557-63, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14709930

RESUMO

AIM: We wanted to understand coping strategies specific to different phases up to two years after radiotherapy, to identify patients who are at higher risk of mood disturbances and to characterise the association between coping strategies and psychosocial adaptation. PATIENTS AND METHODS: From 1997 to 2001, 2,169 patients with different diagnoses were screened (27.8% refused to participate). Data of 276 patients from the beginning of radiotherapy (ti1) and 5 follow-up investigations (ti6/2 years) could be analysed. With the FKV (Freiburg Questionnaire Coping with Disease) cancer-specific coping aspects were assessed. The association between coping styles and psychosocial adaptation was evaluated using the Questionnaire on Stress in Cancer Patients (QSC) and the questionnaire on Functional Assessment of Cancer Treatment (FACT-G). RESULTS: 'Active problem-orientated' coping and 'distractions' are the most important coping strategies. Only 'active problem-orientated' and 'depressive' coping showed a significant decrease. We observed higher means on the scales of the FKV in women. Marital status (single, married, divorced/widowed) had a significant influence on active problem-orientated coping and spirituality. Age, children, education, T/M status and curative/ palliative intention of treatment had no influence on coping styles. Breast cancer patients and lymphoma patients demonstrated the highest use of coping strategies after radiotherapy with a significant decrease of 'active problem-orientated coping'. Depressive coping and minimizing importance at ti1 were associated with high psychosocial distress and low quality of life (QoL) at ti6. CONCLUSION: The correlation of coping mechanisms at the beginning of radiotherapy with low QoL and high psychosocial stress at 2 years could help to identify patients at risk for low psychosocial adaptation. Psycho-oncologically trained teams of physicians would best correspond to this profile of needs and would contribute significantly to an ameliorated adaptation of patients to cancer which could lead to higher life satisfaction.


Assuntos
Adaptação Psicológica , Neoplasias/psicologia , Neoplasias/radioterapia , Radioterapia/psicologia , Papel do Doente , Transtornos de Adaptação/diagnóstico , Transtornos de Adaptação/psicologia , Adulto , Idoso , Neoplasias da Mama/psicologia , Neoplasias da Mama/radioterapia , Feminino , Seguimentos , Humanos , Linfoma/psicologia , Linfoma/radioterapia , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos/psicologia , Inventário de Personalidade , Resolução de Problemas , Prognóstico , Qualidade de Vida/psicologia , Ajustamento Social , Apoio Social , Fatores Socioeconômicos , Espiritualidade
9.
Strahlenther Onkol ; 177(10): 530-7, 2001 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-11680018

RESUMO

PURPOSE: Radiotherapy brings a tumor patient into a special life situation in which different variables play a role of often unknown importance. The goal of this study was to investigate disease specific stress of tumor patients at the beginning of radiotherapy with established psychodiagnostic questionnaires and to evaluate the effect on psychosocial support requirement in order to reduce stress and to improve quality of life and compliance during radiotherapeutical treatment. PATIENTS AND METHODS: 732 patients were screened, of whom 446 (60.9%) fulfilled the criteria for inclusion (refusals 21.0%, low karnorsky performance status 6.6%, management problems 3.4%, language barriers 3.0%, cognitive restrictions 2.6%, death 2.5%). Disease specific aspects of stress in the questionnaire (Fragebogen zur Belastung von Krebspatienten, FBK), life situation (LS) and self-defined care requirements (BB) (Figure 1) were self-rated by patients with different tumor types before radiotherapy. Medical and sociodemographic data were also documented. We investigated 446 patients (262 male, 184 female; median age 60.0 years) with different diagnoses (Table 1). RESULTS: Stress was observed mainly due to reduction of efficiency, anxiety and pain on the subscales (Figure 2). Women had a significant higher stress on subscales of pain (p = 0.016) and anxiety (p = 0.009) (Table 2), patients younger than 45 years in the subscale information (p = 0.002) and patients older than 45 and younger than 60 years in the subscale anxiety (p = 0.002) and the total score (p = 0.003) (Table 3). Patients with mamma carcinoma had the highest the stress (Table 4). The maximum percentages of patients under high stress were found for the subscales of efficiency (43%) and anxiety (40%). The support requirement was characterized by the need of more medical information and dialogue with the doctor. We saw a significant correlation of high stress and high care requirement (Tables 5 and 6). CONCLUSIONS: Psychosocial support should be founded on psychosocial stress diagnostic and self-defined care requirement.


Assuntos
Neoplasias/psicologia , Neoplasias/radioterapia , Apoio Social , Estresse Psicológico/etiologia , Adulto , Feminino , Humanos , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Fatores Sexuais , Inquéritos e Questionários
10.
Eur J Cancer ; 37(13): 1599-608, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11527684

RESUMO

In this phase II study, activity and safety of neoadjuvant regional hyperthermia (RHT) combined with chemotherapy was investigated in 59 patients with primary advanced or recurrent high-risk soft-tissue sarcoma (STS). Patients received four EIA cycles consisting of etoposide, ifosfamide and doxorubicin combined with RHT followed by surgical resection and adjuvant treatment. The overall objective response (OR) rate was 17%, with one complete (2%) and eight partial (15%) responses. In addition, 13 minor responses (25%) were seen. At time of surgery, complete necrosis (pCR) occurred in 6 patients and >75% necrosis (favourable histological response (FHR)) in 12 patients. At the completion of protocol treatment, 36 patients were rendered disease-free which was significantly associated with the initial radiographic and/or pathological tumour response (P=0.004). Treatment-related toxicity was acceptable overall. At a medium follow-up of 82 months, local treatment failure occurred in 33 patients, median overall survival (OS) was 52 months, and the 5-year survival rate was 49% (95% confidence interval (CI): 36-61%). OS which did not differ for extremity versus non-extremity STS (P=0.21) was better for patients responding to EIA combined with RHT (P<0.01).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hipertermia Induzida/métodos , Sarcoma/terapia , Adulto , Idoso , Quimioterapia Adjuvante/efeitos adversos , Quimioterapia Adjuvante/métodos , Estudos de Coortes , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Seguimentos , Humanos , Ifosfamida/administração & dosagem , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/terapia , Radioterapia Adjuvante/métodos , Fatores de Risco , Resultado do Tratamento
11.
Onkologie ; 24(6): 553-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11799310

RESUMO

BACKGROUND: Chemo-radiotherapy is superior to radiotherapy alone in the treatment of advanced, inoperable head and neck cancer. The long-term treatment results, the induction of second malignant tumors, and other long-term toxicities are not well defined. PATIENTS AND METHODS: 100 consecutive patients with advanced head and neck cancer who were treated at our center were studied. Treatment results, survival, the occurrence of late complications, and second malignant tumors (SMT) were investigated. 78 patients were treated with a protocol combining cisplatinum, 5-fluorouracil, folinic acid and hyperfractionated irradiation. 22 patients were treated with other chemo-radiotherapy protocols. The relative risk of developing an SMT was compared with that within the normal population. RESULTS: The cumulative total probability of survival was 51.1% at 2 years and 38.7% at 4 years. The probability of relapse-free survival was 39.9% at 2 years and 36.7% at 4 years. A total of 7 patients developed SMT (4 cases of lung cancer, 2 colon cancers, 1 skin cancer). After 6 years, a cumulative risk of SMT of 8.7% was observed. The relative risk of developing an SMT was significantly increased (4.45-fold in males) compared with a normal population. 13 of 38 evaluable patients (34.2%) had severe late complications like fibrosis of soft tissues, nerve lesions, or were dependent on tracheal cannulas. CONCLUSIONS: The treatment results and long-term prognoses in our population of unselected high-risk patients are unsatisfactory, but comparable to those from multicenter studies. About 35% of patients become long-term (> 4 years) survivors. SMT generally occur early, have a poor prognosis and, most likely, are not treatment-related. Approximately 30% of long-term survivors have severe, often incapacitating late effects. The treatment and - if possible - prevention of these late effects is important for the quality of life of patients who survived advanced head and neck cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Otorrinolaringológicas/radioterapia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Radioisótopos de Cobalto/uso terapêutico , Terapia Combinada , Intervalo Livre de Doença , Fracionamento da Dose de Radiação , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Seguimentos , Humanos , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Mitomicina/efeitos adversos , Estadiamento de Neoplasias , Neoplasias Induzidas por Radiação/etiologia , Segunda Neoplasia Primária/etiologia , Neoplasias Otorrinolaringológicas/tratamento farmacológico , Neoplasias Otorrinolaringológicas/mortalidade , Neoplasias Otorrinolaringológicas/patologia , Lesões por Radiação/etiologia , Teleterapia por Radioisótopo , Taxa de Sobrevida
12.
Onkologie ; 23(6): 565-570, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11441262

RESUMO

BACKGROUND: In the framework of a prospective longitudinal study, the quality of life (QoL) and support requirements of patients from a university hospital department of radiotherapy were evaluated for the first time by means of established psychodiagnostic questionnaires. PATIENTS AND METHODS: At first, 732 patients were screened, of whom 446 (60.9%) fulfilled the criteria for inclusion; 39.1% did not (refusals 21.0%, low Karnofsky performance status 6.6%, management problems 3.4%, language barriers 3.0%, cognitive restrictions 2.6%, death 2.5%). Disease-specific aspects of QoL (Functional Assessment of Cancer Treatment - General, FACT-G) and moderating variables [Social Support Scale (SSS), Disease Coping (FKV), Self-Assessment Depression Scale (SDS), and Self-Defined Care Requirements (BB)] were self-rated by patients with different tumor types before radiotherapy (T1), after radiotherapy (T2), and 6 weeks after the end of radiotherapy (T3). We studied 265 patients (157 male, 108 female; median age 58.6 years) with complete data of three time points. RESULTS: In general, QoL of patients decreased significantly over all time points in all subscales. Social support was rated high and remained constant throughout the treatment. Apparent coping mechanisms were active problem-oriented coping, leisure activities, and self-support. The patients' depression proved to be an important and constant factor without significant changes. The support requirement is characterized by the need for more medical information and dialogue with a physician. CONCLUSIONS: Early specific support from personnel with radiotherapeutic skills, during the disease-coping process as well as during rehabilitation, should be a permanent component of an integrated radiooncological treatment schedule. Copyright 2000 S. Karger GmbH, Freiburg

13.
Stat Med ; 18(16): 2123-34, 1999 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-10441768

RESUMO

In failure time analyses, time-dependent covariates are only rarely used. In some clinical studies, however, consideration of available covariate information over time could be relevant to understanding complex disease processes. We propose the time-dependent Cox model and the linear model of Aalen as two possible approaches for such time-dependent survival analyses. The approaches are illustrated with the data of the Stanford Heart Transplantation Study and a study of malignant glioma. Differences between these models and the baseline analysis are discussed.


Assuntos
Modelos Lineares , Modelos de Riscos Proporcionais , Análise de Sobrevida , Adulto , Glioma/mortalidade , Glioma/terapia , Transplante de Coração/mortalidade , Humanos , Avaliação de Estado de Karnofsky , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Software , Fatores de Tempo
14.
Ann Hematol ; 78(12): 544-54, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10647878

RESUMO

The occurrence of second malignancies (SM) is an important late event following the treatment of Hodgkin's disease (HD). We sought to determine the incidence, the risk factors, and the prognosis of SM in our population of patients with HD. A total of 1120 patients diagnosed with HD were registered at six participating institutions in Munich (calendar period 1974-1994). The mean follow-up for the development of SM was 9.1 years. A cumulative treatment score was calculated for both radio- and chemotherapy. The relative and absolute risks of SM were established. All SM were investigated for response to treatment and outcome. We observed 85 SM [eight leukemias, 22 non-Hodgkin's lymphomas (NHL), two plasma cell neoplasias, and 53 solid tumors]. Five patients developed third malignancies. The relative risk of developing a second neoplasm was compared with that within the normal population and was 3.1-fold. The risk varied according to the category of SM. Higher relative risks (20.5 and 25.9-fold), but lower absolute risks were observed for leukemias and non-Hodgkin's lymphomas. Solid tumors had lower relative risks (1.8-fold). Splenectomy increased the risk of SM (relative risk 4.4-fold versus 2.7-fold). The risk of SM did not correlate with the initial treatment (radio- or chemotherapy) and did not decrease with prolonged follow-up. The cumulative intensity of radiotherapy, chemotherapy, or the two modalities combined correlated with the risk of SM. Since some cases occurred early after diagnosis, not all second neoplasms can be considered treatment-associated. After 15 years, an actuarial risk of 11.7% was calculated for all SM, of 1.0% for leukemias, of 3.0% for NHL, and of 7.7% for solid tumors. The prognosis of SM varied between good (thyroid cancer, melanoma: median survival 5+ years), average (breast cancer, NHL), and poor (acute myeloid leukemias, lung cancers: median survival 9 months). With the exception of NHL, second cancers often occurred in topographic relation to the field of previous radiotherapy. Taken together, in our patient population, we observed all three categories of SM (solid tumors, leukemias, NHL). The risk for second leukemias is lower than in previous studies, whereas the risk of second NHL is somewhat higher. We confirm that splenectomy is a possible risk factor for SM. Even after correction for the age-specific cancer incidence, treatment intensity is associated with the development of second malignant tumors. Continued follow-up is mandatory after treatment for HD. Since the prognosis of most SM is unfavorable, early recognition and prevention are of the utmost importance.


Assuntos
Doença de Hodgkin/terapia , Segunda Neoplasia Primária/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Alemanha/epidemiologia , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/radioterapia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Segunda Neoplasia Primária/terapia , Fatores de Risco , Resultado do Tratamento
15.
Blood ; 92(6): 1898-909, 1998 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9731046

RESUMO

In contrast to childhood acute lymphoblastic leukemia (ALL), the cell-biological features, clinical characteristics, and treatment outcome of CD10(-) pro-B ALL have not yet been determined in larger series of adult patients. Therefore, we studied 57 adult patients with newly diagnosed pro-B ALL (median age, 30 years) enrolled in two consecutive German multicenter ALL studies (03/87 and 04/89). Extensive immunophenotypic characterization of leukemic blasts could be performed on all patients, whereas adequate cytogenetic data were available in 33 cases and molecular studies in 18 cases, using reverse transcription-polymerase chain reaction to detect MLL-AF-4 transcripts. Twenty-two patients demonstrated a t(4;11)(q21;q23) and/or MLL-AF-4 rearrangements, and 6 patients had other structural abnormalities, including a t(9;22)(q34;q11) (N = 2). Nine patients had a normal karyotype. Patients with 11q23 abnormalities tended to be younger (median age, 29 years) and were characterized by male predominance (64%), hyperleukocytosis (median leukocyte count, 168 x 10(9)/L), and a frequent coexpression of CD65s (64%) as compared with patients with other cytogenetic abnormalities or a normal karyotype. Twelve of 16 (75%) pro-B ALL patients in study 03/87 and 30 of 41 (73%) in study 04/89 achieved a complete remission (CR). Sixteen of 30 patients in study 04/89 remain in continuous CR (CCR) in contrast to only 2 of 12 patients in study 03/87. Interestingly, all 7 patients treated with high-dose cytarabine and mitoxantrone as consolidation in study 04/89 remain alive and leukemia-free. One patient in study 03/87 and 8 in study 04/89 underwent autologous (N = 2) or allogeneic (N = 7) bone marrow transplantation (BMT). The median remission duration was 420 days for patients in study 03/87 and has not yet been reached in study 04/89. The median survival time of all pro-B ALL patients was 571 days in study 03/87 and 747 days in study 04/89. Among the 22 patients with a t(4;11) and/or MLL-AF-4 rearrangements, 17 achieved a CR and 8 are still in CCR, of whom 4 underwent an allogeneic BMT. Remission duration and overall survival did not differ significantly between pro-B ALL patients with 11q23 abnormalities and those with a normal karyotype or other structural abnormalities. These data indicate that intensification of postremission treatment may improve the prognosis of adult pro-B ALL, including patients with a t(4;11).


Assuntos
Imunofenotipagem , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adolescente , Adulto , Idoso , Aberrações Cromossômicas/genética , Aberrações Cromossômicas/patologia , Transtornos Cromossômicos , Feminino , Humanos , Cariotipagem , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Indução de Remissão , Resultado do Tratamento
16.
Blood ; 89(7): 2291-7, 1997 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9116271

RESUMO

Among high-grade malignant non-Hodgkin's lymphomas the updated Kiel classification identifies three major B-cell entities: centroblastic (CB), B-immunoblastic (B-IB), and B-large cell anaplastic (Ki-1+) (now termed anaplastic large cell [CD30+], [B-ALC]). The clinical prognostic relevance of this distinction was evaluated in a randomized prospective treatment trial (COP-BLAM/IMVP-16 regimen randomly combined +/- radiotherapy in complete responders) conducted in adult (age 15 to 75) patients with Ann Arbor stage II-IV disease (n = 219) diagnosed by optimal histomorphology (Giemsa staining) and by immunohistochemistry. Overall survival was significantly better in CB lymphoma as compared to B-IB (P = .0002) or B-ALC (P = .046). Relapse-free survival was worse for B-IB (P = .0003) as compared to CB lymphomas. The prognostic differences between CB and B-IB were confirmed by multivariate analyses including the risk factors of the International Index. Overall survival was significantly determined by performance status (P = .0003), serum-LDH (P = .036), and B-IB histology subtype (P = .036). Relapse-free survival was influenced by age (P = .007) and histological subtype (P = .007). Thus, the diagnosis of the CB and B-IB lymphomas by the histological criteria of the Kiel classification was identified as an independent prognostic factor in diffuse large B-cell lymphomas.


Assuntos
Linfoma Difuso de Grandes Células B/classificação , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Anaplásico de Células Grandes/mortalidade , Linfoma Imunoblástico de Células Grandes/mortalidade , Adolescente , Adulto , Fatores Etários , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bleomicina/administração & dosagem , Terapia Combinada , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Humanos , Ifosfamida/administração & dosagem , Tábuas de Vida , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/radioterapia , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Linfoma Anaplásico de Células Grandes/radioterapia , Linfoma Imunoblástico de Células Grandes/tratamento farmacológico , Linfoma Imunoblástico de Células Grandes/radioterapia , Masculino , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Análise Multivariada , Prednisona/administração & dosagem , Procarbazina/administração & dosagem , Prognóstico , Estudos Prospectivos , Radioterapia Adjuvante , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento , Vincristina/administração & dosagem
17.
Gesundheitswesen ; 59(2): 95-101, 1997 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-9156632

RESUMO

One of the common features of the five Public Health Research Centres of Germany lies in quality assurance and quality improvement of their research activities. The institutionalisation of systems of quality improvement of Public Health Research has to be regarded as innovative, hitherto unparalleled, in the German context. The article deals with the demands on quality improvement confronting empirical research, the possibilities of coming to terms with this challenge, and still unresolved problems of implementation. Demands will be outlined in discussing quality criteria and processes of empirical research, paying special attention to differences between qualitative and quantitative designs of inquiry. The concept of quality improvement, developed in the Munich Public Health Research Centre, applies two basic strategies to meet these demands: enhancement of the transparency of the research process, and the training of research staff. Instruments for quality improvement are introduced: some of them may be applied by the research team itself (such as study protocol, research diary, team discussion) some of them have to be realised by external staff, especially responsible for the process of quality improvement, in cooperation with the research team (quality circles, training, compilation of written material). In conclusion, the implementation of instruments of this kind is discussed, concentrating on the problematic cooperation between research team and external staff.


Assuntos
Programas Nacionais de Saúde/tendências , Saúde Pública/tendências , Garantia da Qualidade dos Cuidados de Saúde/tendências , Pesquisa/tendências , Previsões , Alemanha , Humanos
18.
Hepatology ; 16(3): 707-14, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1505913

RESUMO

The efficacy and safety of ursodeoxycholic acid for the treatment of primary sclerosing cholangitis were evaluated in a prospective, randomized, double-blind, placebo-controlled trial. Fourteen patients with primary sclerosing cholangitis documented by cholestatic serum enzyme pattern, liver histological appearance and endoscopic retrograde cholangiography were included in the trial. Six patients received ursodeoxycholic acid (13 to 15 mg/kg body wt/day), and eight patients received placebo. Two patients had to be withdrawn from the study, one because of UDCA-related diarrhea and the other because of worsening of the disease during placebo treatment. Patients in the ursodeoxycholic acid group improved significantly during 1 yr of treatment with respect to serum levels of bilirubin (median = -50%), alkaline phosphatase (median = -67%), gamma-glutamyltransferase (median = -53%), AST (median = -54%) and ALT (median = -36%) compared with the placebo group, but not with respect to serum levels of hydrophobic bile acids. During ursodeoxycholic acid treatment, histopathological features also improved significantly, as evaluated by multiparametric score. Expression of human leukocyte antigen class I molecules appeared to be markedly reduced on liver cells after ursodeoxycholic acid treatment. We conclude that ursodeoxycholic acid is beneficial in reducing disease activity in patients with primary sclerosing cholangitis.


Assuntos
Colangite Esclerosante/tratamento farmacológico , Ácido Ursodesoxicólico/uso terapêutico , Adolescente , Adulto , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Aspartato Aminotransferases/sangue , Ácido Quenodesoxicólico/sangue , Colangite Esclerosante/sangue , Colangite Esclerosante/patologia , Ácido Cólico , Ácidos Cólicos/sangue , Ácido Desoxicólico/sangue , Diarreia/induzido quimicamente , Método Duplo-Cego , Feminino , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
19.
Hepatology ; 14(6): 1136-41, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1959863

RESUMO

A prospective, double-blind, randomized, single-center study was conducted to compare ursodeoxycholic acid alone with the combination of ursodeoxycholic acid and chenodeoxycholic acid for dissolution therapy of gallstone fragments after shock wave lithotripsy. Patients with single radiolucent gallstones up to 30 mm in diameter or up to three stones of similar total volume received either 750 mg ursodeoxycholic acid alone (group A, n = 138) or the combination of 500 mg ursodeoxycholic acid and 500 mg chenodeoxycholic acid (group B, n = 144) in a single bedtime dose. The bile acids were administered from 2 wk before electrohydraulic lithotripsy until 3 mo beyond complete disappearance of all fragments. Patient's characteristics, stones (group A, 82% single stones, maximum diameter 19 +/- 5 mm, mean +/- S.D.; group B, 82% single stones, 18 +/- 5 mm), lithotripsy treatment and follow-up period were not different between the two groups. Between the two groups, no statistically significant difference was found in the time required for complete clearance of the fragments (group A, median time = 15 mo; group B, median time = 13 mo; p = 0.7). At 12 mo after lithotripsy, the probability of complete clearance was 46% +/- 5% in group A and 49% +/- 5% in group B. Diarrhea occurred significantly more often in group B than in group A (p less than 0.001) and was the main reason for withdrawal of randomized medication. Severe adverse effects of the bile acids were not observed. It is concluded that monotherapy with ursodeoxycholic acid is as efficient as the combination of ursodeoxycholic acid and chenodeoxycholic acid for fragment dissolution after lithotripsy.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ácido Quenodesoxicólico/uso terapêutico , Colelitíase/tratamento farmacológico , Ácido Ursodesoxicólico/uso terapêutico , Dor Abdominal/etiologia , Adulto , Ácido Quenodesoxicólico/efeitos adversos , Diarreia/induzido quimicamente , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Litotripsia/efeitos adversos , Fígado/enzimologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ácido Ursodesoxicólico/efeitos adversos
20.
Lancet ; 337(8749): 1055-8, 1991 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-1673492

RESUMO

Philadelphia chromosome-positive acute lymphoblastic leukaemia (ALL) is most common in adults and is associated with poor prognosis. Since karyotypic identification of the Philadelphia translocation has been hampered by technical difficulties, we used the polymerase chain reaction (PCR) to look for the BCR-ABL rearrangement in stored samples from a selected group of 314 German ALL patients. BCR-ABL transcripts were found in 77 of 179 adults and were restricted to those with B-precursor leukaemias. 55% of adult common ALL patients had BCR-ABL and its presence correlated with poor overall survival and remission duration. Of 135 children with common ALL, 5 (6%) primary cases and 8 (17%) with recurrent neoplasias were PCR-positive. We recommend prospective evaluation of BCR-ABL analysis with PCR in patients with a B-precursor leukaemia.


Assuntos
Quimera/genética , Proteínas de Fusão bcr-abl/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , RNA Mensageiro/análise , RNA Neoplásico/análise , Adulto , Sequência de Bases , Criança , Alemanha/epidemiologia , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/epidemiologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Dados de Sequência Molecular , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/mortalidade , Reação em Cadeia da Polimerase/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Prognóstico , Estudos Prospectivos , Transcrição Gênica
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