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1.
Ann Oncol ; 16(9): 1469-76, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15956038

RESUMO

BACKGROUND: The role of anthracyclines has been extensively studied in adjuvant chemotherapy, but much less in the primary chemotherapy of early breast carcinoma. This study, comparing CMF (cyclophosphamide, methotrexate, 5-fluorouracil) with the rotational anthracycline-containing regimen CMFEV (CMF plus epirubicin and vincristine) administered as primary chemotherapy, demonstrated a significant increase in clinical complete response in premenopausal women. We report the long-term results. PATIENTS AND METHODS: Two hundred and eleven patients with stage I or II palpable breast carcinoma and a tumour diameter of >2.5 cm were randomised to receive CMF or CMFEV for four cycles before surgery. After surgery, the patients in both arms received adjuvant CMF for three cycles. RESULTS: In the study population as a whole, there was a non-significant 20% reduction in mortality and relapse rates in the CMFEV arm. However, the effect of the experimental regimen was only found in premenopausal patients, especially in terms of relapse-free survival (P=0.07) and locoregional relapse-free survival (P=0.0009), thus mirroring the effect on response rates. After 10 years, the proportions of premenopausal patients free from locoregional relapse as a first event in the CMF and CMFEV groups were 68% and 97%, respectively. No relevant differences were found in postmenopausal patients. CONCLUSION: The overall results of this study showed that the greater activity of the experimental anthracycline-containing combination over CMF as primary chemotherapy in premenopausal patients translated into long-term effects in the same subgroup.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Epirubicina/administração & dosagem , Vincristina/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Ciclofosfamida/administração & dosagem , Ciclofosfamida/uso terapêutico , Intervalo Livre de Doença , Fluoruracila/administração & dosagem , Fluoruracila/uso terapêutico , Humanos , Metotrexato/administração & dosagem , Metotrexato/uso terapêutico , Resultado do Tratamento
2.
Am J Clin Oncol ; 22(6): 559-67, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10597739

RESUMO

In a retrospective analysis of a series of clinical trials by Levin and Hryniuk in 1987, the average relative dose intensity of first-line chemotherapy for advanced ovarian cancer correlated significantly with clinical response and survival, and cisplatin was the only drug for which the outcome correlated with the individual drug relative dose intensity. There was a need to test whether and to what extent this evidence would be confirmed in a prospective evaluation. In this study 101 patients with advanced ovarian carcinoma were randomized to receive the same total dose of cisplatin but at the conventional 3-weekly schedule (CTWS) (100 mg/m2 every 3 weeks for six cycles) (51 patients) or at an experimental accelerated weekly schedule (AWS) (100 mg/m2 every week for two triplets of three cycles separated by a 5-week interval) (50 patients). To benefit from a multidrug regimen at the same extent, patients in both arms sequentially received four cycles of doxorubicin and cyclophosphamide. The median follow-up period of this study is 9.7 years. In 42 and 40 patients of the two arms having evaluable response, the clinical complete response rates to cisplatin were 14% and 22% and the complete plus partial response rates were 48% and 55% in the CTWS and in the AWS arm, respectively. These differences were not statistically significant. However, the survival curves were similar during the first 2 years but clearly diverged thereafter in favor of the AWS arm (p = 0.07). At 5 years, 12% and 30% of the patients were still alive in the CTWS and in the AWS arm, respectively. Hematologic toxicity was not relevant in either arm of the study. Nonhematologic toxicity, especially ototoxicity, was substantial and significantly higher in the AWS arm. Although statistically nonsignificant, this AWS regimen of cisplatin is associated with long-term better survival compared to the CTWS regimen in advanced ovarian carcinoma. This accelerated approach administering cisplatin should be further investigated, especially in patients with low residual disease after primary surgery.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma/tratamento farmacológico , Cisplatino/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Adulto , Idoso , Antibióticos Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos Alquilantes/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/cirurgia , Quimioterapia Adjuvante , Cisplatino/efeitos adversos , Ciclofosfamida/administração & dosagem , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Esquema de Medicação , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasia Residual , Neoplasias Ovarianas/cirurgia , Estudos Prospectivos , Indução de Remissão , Taxa de Sobrevida , Resultado do Tratamento
3.
Breast Cancer Res Treat ; 56(2): 125-32, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10573105

RESUMO

We designed three new four-drug cisplatin-containing combinations and evaluated their activity in a randomized phase II study including patients with locally advanced (stage III) and locally recurrent breast carcinoma. All combinations included methotrexate (M) on day 1 and cisplatin (P) on day 2 (MVAC-like combinations) and differed from one another by the addition of Epirubicin (Epi), Vincristine (V), Etoposide (E), Mitomycin (Mi). Based on the administered agents, they were named MPEMi, MPEpiE, MPEpiV. The combinations were randomly assigned to 101 patients, 57 with locally advanced and 44 with locally recurrent breast carcinoma. Response was evaluated after 4 cycles. The complete response (CR) rates were 7% and 43% and the CR plus partial response (PR) rates were 84% and 89% in locally advanced and in locally recurrent disease, respectively. In locally advanced disease, a pathologic CR (pCR) was assessed in seven of 57 patients (12%). There were no significant differences among the three combinations. The toxicities were at times severe, but generally tolerable, as demonstrated by the high cumulative doses of the drugs received by the patients. In conclusion, these three innovative chemotherapy regimens induced high CR plus PR rates in the neoadjuvant treatment of stage III and of locally recurrent breast carcinoma, and a high rate of pCR in stage III disease. These regimens warrant testing in phase III trials.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Cisplatino/administração & dosagem , Epirubicina/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Humanos , Leucovorina/administração & dosagem , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Terapia Neoadjuvante , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Vincristina/administração & dosagem
4.
J Biomol Struct Dyn ; 15(5): 861-75, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9619509

RESUMO

Short di- and tripeptides such as Boc-LG-OEt, Boc-VG-OEt and Boc-VGG-OH, corresponding to abundant repetitive sequences in elastin, have been extensively studied both in solid state, by X-ray diffraction, and in solution by circular dicroism and nuclear magnetic resonance. Furthermore, theoretical procedures such as simulated annealing and molecular dynamics were also performed on these peptides. In general, the results indicate that no one single structure (be folded or extended) could be representative for these sequences in the protein, but rather that a multiplicity of interconverting conformers, ranging from folded to extended structures, should be considered. In any case, these structures, e.g. beta-turns, polyglycine II and beta-conformations, are those previously suggested to participate to conformational equilibria of elastin.


Assuntos
Elastina/química , Peptídeos/química , Dicroísmo Circular , Modelos Moleculares , Ressonância Magnética Nuclear Biomolecular , Conformação Proteica , Difração de Raios X
5.
J Pept Sci ; 3(2): 110-22, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9230476

RESUMO

A series of N- and C-protected, monodispersed homo-oligopeptides (to the dodecamer level) from the small-ring alicyclic C alpha, alpha-dialkylated glycine 1-aminocyclobutane-1-carboxylic acid (Ac4c) and two Ala/Ac4c tripeptides were synthesized by solution methods and fully characterized. The conformational preferences of all the model peptides were determined in deuterochloroform solution by FT-IR absorption and 1H-NMR. The molecular structures of the amino acid derivatives Z-Ac4c-OH and Z2-Ac4c-OH, the tripeptides Z-(Ac4c)3-OtBu, Z-Ac4c-(L-Ala)2-OMe and Z-L-Ala-Ac4c-L-Ala-OMe, and the tetrapeptide Z-(Ac4c)4-OtBu were determined in the crystal state by X-ray diffraction. The average geometry of the cyclobutyl moiety of the Ac4c residue was assessed and the tau(N-C alpha-C') bond angle was found to be significantly expanded from the regular tetrahedral value. The conformational data are strongly in favour of the conclusion that the Ac4c residue is an effective beta-turn and helix former. A comparison with the structural propensities of alpha-aminoisobutyric acid, the prototype of C alpha, alpha-dialkylated glycines, and the other extensively investigated members of the family of 1-aminocycloalkane-1-carboxylic acids (Acnc, with n = 3, 5-8) is made and the implications for the use of the Ac4c residue in conformationally constrained peptide analogues are briefly examined.


Assuntos
Aminoácidos Cíclicos , Aminoácidos/química , Modelos Moleculares , Peptídeos/química , Peptídeos/síntese química , Conformação Proteica , Cristalização , Espectroscopia de Ressonância Magnética , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
6.
J Pept Sci ; 2(1): 14-27, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9225242

RESUMO

A complete series of terminally blocked, monodispersed homo-oligopeptides (to the pentamer level) from the sterically demanding, medium-ring alicyclic C (alpha,alpha)-disubstituted glycine 1-aminocyclooctane-1-carboxylic acid (Ac8c), and two Ala/Ac8c tripeptides, were synthesized by solution methods and fully characterized. The preferred conformation of all the oligopeptides was determined in deuterochloroform solution by IR absorption and 1H-NMR. The molecular structures of the amino acid derivative Z-Ac8c-OH, the dipeptide pBrBz-(Ac8c)2-OH and the tripeptide pBrBz-(Ac8c)3-OtBu were assessed in the crystal state by X-ray diffraction. Conformational energy computations were performed on the monopeptide Ac-Ac8c-NHMe. Taken together, the results obtained strongly support the view that the Ac8c residue is an effective beta-turn and helix former. A comparison is also made with the conformational preferences of alpha-aminoisobutyric acid, the prototype of C (alpha,alpha)-disubstituted glycines, and of the other members of the family of 1-aminocycloalkane-1-carboxylic acids (Acnc with n = 3, 5-7) investigated so far. The implications for the use of the Ac8c residue in peptide conformational design are considered.


Assuntos
Aminoácidos Cíclicos , Aminoácidos/química , Glicina/análogos & derivados , Peptídeos/química , Conformação Proteica , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Ácido gama-Aminobutírico/química
7.
Bioorg Med Chem ; 3(9): 1211-21, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8564412

RESUMO

A N alpha-blocked, Aib-rich octapeptide methylamide containing two N omega-benzoylated L-Lys residues at positions 3 and 6 was synthesized by solution methods and fully characterized. A solution and crystal-state conformational analysis, performed by using FT-IR, 1H NMR, CD, and X-ray diffraction techniques, showed that the peptide is folded into a regular, right-handed 3(10)-helix stabilized by seven consecutive N-H...O=C intramolecular H-bonds of the beta-turn III type. The two benzamidobutyl L-Lys side chains, located on the same side of the helix after one complete turn, generate a cleft the minimal width of which was found to be 3.47 A.


Assuntos
Oligopeptídeos/química , Estrutura Secundária de Proteína , Sequência de Aminoácidos , Sítios de Ligação , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Moldes Genéticos , Difração de Raios X
8.
Acta Crystallogr C ; 51 ( Pt 4): 663-6, 1995 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-7619339

RESUMO

cyclo-(Prolyl-prolyl-phenylalanyl-phenylalanyl- alpha-aminoisobutyryl-alpha-aminoisobutyryl-isoleucyl-D-alan yl-valyl) ([Aib5,6-D-Ala8]-cyclolinopeptide A), grown from benzene/acetonitrile mixture, crystallizes with one acetonitrile and two water molecules. The molecular structure is almost identical to that obtained from methanol/water. The dimension of the solvent channels found in these structures is reduced in the present one, but the intramolecular hydrogen-bond pattern is preserved. The Pro1-Pro2 peptide unit is cis (omega = 8 degrees); all others are trans.


Assuntos
Acetonitrilas , Benzeno , Peptídeos Cíclicos/química , Sequência de Aminoácidos , Cristalização , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular
9.
Biopolymers ; 34(2): 273-84, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8142593

RESUMO

The conformational analysis of [sequence: see text] the disulphide cyclopeptide-related cyclolinopeptide A, has been carried out by solid state methods using x-ray diffraction techniques, in solution by nmr, CD, ir spectroscopies, and by molecular dynamics (MD) analysis. The structure of the monoclinic form, obtained from ethanol (a = 11.303(2) A, b = 14.467(8) A, c = 12.355(2) A, beta(degree) = 109.40(1), space group P2(1), Z = 2) presents two transannular H bonds with the formation of one type VIa beta-turn involving the C = O of the urethane moiety and the Phe3 NH, and an intramolecular H bond between the C = O of urethane group and the Phe4 NH. In the solid state all the peptide bonds are in the trans configuration with the exception of a cis peptide bond occurring between the Cys1 and Pro2 residues; the linkage S-S assumes right-handed chirality. The conformational study in solution by nmr spectroscopy indicates that the peptide is very flexible and that some conformer families are present at room temperature both in polar and apolar solvents. CD studies confirm that this cyclic system tends to give rise to a complex mixture of quasi-isoenergetic conformations, favored by the flexibility of the disulphide bridge and by the isomerism of the Xxx-Pro bond. MD studies carried out in vacuo and in solution shows that the structure determined by solid state represents a energy minimum. All hydrogen bonds found in the crystalline state are correctly reproduced in vacuo and in solution simulations.


Assuntos
Peptídeos Cíclicos/química , Sequência de Aminoácidos , Dados de Sequência Molecular , Oligopeptídeos/química , Conformação Proteica , Soluções , Termodinâmica
10.
Ann Oncol ; 5(1): 93-4, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8172801

RESUMO

BACKGROUND: The M-VAC combination is very effective in bladder carcinoma, as are all four drugs, as single-agent, in advanced breast carcinoma. PATIENTS AND METHODS: M-VAC was given in 27 patients, 4 with locally advanced breast carcinoma, 3 with local recurrence and 20 with distant metastases. The median age was 51 (range 25; 70). Eleven of the 20 patients with metastatic disease has been previously treated with a different chemotherapy. RESULTS: 15 of 26 evaluable patients responded, with 9 (35%) complete remissions and 6 partial responses. The overall response rate (CR plus PR) was 57% (95% confidence interval 38% to 76%). In patients with metastatic disease the median duration of response was 7 months (range 4+; 36+), median time to progression 5 months (range 1; 36+) and median duration of survival 17 months (range 1; 40+). CONCLUSION: The M-VAC combination is very effective in locally advanced, locally recurrent and metastatic breast carcinoma. Further trials are warranted to evaluate whether the activity of this combination is partially schedule-dependent.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Adulto , Idoso , Neoplasias da Mama/patologia , Cisplatino/uso terapêutico , Doxorrubicina/uso terapêutico , Feminino , Seguimentos , Humanos , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Metástase Neoplásica , Resultado do Tratamento , Vimblastina/uso terapêutico
11.
Biopolymers ; 33(7): 1037-49, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8343584

RESUMO

Structural changes can be induced in a peptide by selective substitution of coded alpha-amino acid residues by noncoded alpha-amino acid residues and the consequent production of analogues with modified structure and conformational preferences. In this review article we summarize the solid state structural results and the conformational preferences of two classes of "building blocks": (a) the linear and cyclic symmetrically alpha, alpha-disubstituted glycines in which either two identical n-alkyl groups replace the hydrogen atoms of the glycine residue or a cyclic aliphatic side-chain system is formed by linking the two alpha-carbon side chains, respectively; and (b) the beta-alanine residue. Examples, whenever possible, of the use of these residues for the elucidation of the bioactive conformation in the appropriate biological systems will be given.


Assuntos
Glicina/análogos & derivados , Peptídeos/química , Estrutura Secundária de Proteína , beta-Alanina/análogos & derivados , Sequência de Aminoácidos , Desenho de Fármacos , Modelos Moleculares , Dados de Sequência Molecular , Peptídeos Cíclicos/química , Relação Estrutura-Atividade
12.
Ann Oncol ; 2(9): 687-8, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1742225

RESUMO

The cisplatin (P) and etoposide (E) combination has been found to be active in several types of solid tumors. It has never been previously tested in advanced colorectal cancer. Thirty-three patients with advanced colorectal cancer were treated with this combination. Five patients responded (1 complete and 4 partial responses) with an overall response rate of 15% (95% confidence limits, 3%-27%). Responses were seen in both untreated (3/16) and pretreated (2/17) patients. The median duration of response was 28 weeks (range: 23; 80), the median time to progression was 16 weeks (range 2; 80) and the median survival time for all entered patients was 38 weeks (range: 2; 187+). These results suggest that the PE combination has a low but definite activity in advanced colorectal carcinoma, particularly in previously untreated patients.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Adulto , Idoso , Cisplatino/administração & dosagem , Avaliação de Medicamentos , Etoposídeo/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Indução de Remissão
13.
J Mol Biol ; 214(3): 633-5, 1990 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-2388261

RESUMO

A synthetic, terminally blocked homodecapeptide from the C alpha, alpha-dimethylated glycyl residue alpha-aminoisobutyric acid has been analyzed by single-crystal X-ray diffraction and the structure refined to R = 0.073. The compound crystallizes as a perfect 3(10) helix, stabilized by eight consecutive intramolecular N-H . . . O = C hydrogen bonds. This is the first observation at atomic resolution of a regular polypeptide 3(10) helix as long as three complete turns.


Assuntos
Ácidos Aminoisobutíricos , Oligopeptídeos , Fenômenos Químicos , Físico-Química , Ligação de Hidrogênio , Estrutura Molecular , Conformação Proteica , Difração de Raios X
14.
J Biomol Struct Dyn ; 7(6): 1321-31, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2363848

RESUMO

To assess the minimal peptide length required for the stabilization of the alpha-helix relative to the 3(10)-helix in Aib-rich peptides, we have solved the X-ray diffraction structures of the terminally blocked sequential hexa- and octapeptides with the general formula-(Aib-L-Ala)n-(n = 3 and 4, respectively). The hexapeptide molecules are completely 3(10)-helical with four 1----4 intramolecular N-H . . . O = C H-bonds. On the other hand, the octapeptide molecules are essentially alpha-helical with four 1----5 H-bonds; however, the helix is elongated at the N-terminus, with two 1----4 H-bonds, giving these molecules a mixed alpha/3(10)-helical character. In both compounds the right-handed screw sense of the helix is dictated by the presence of the Ala residues of L-configuration. This study represents the first experimental proof for a 3(10)----alpha-helix conversion in the crystal state induced by peptide backbone lengthening only.


Assuntos
Peptídeos , Conformação Proteica , Fenômenos Químicos , Físico-Química , Ligação de Hidrogênio , Estrutura Molecular , Difração de Raios X
15.
Am J Clin Oncol ; 13(3): 226-32, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2189288

RESUMO

Forty-nine patients with locally advanced breast carcinoma were prospectively randomized to be treated with either CMF or CMF plus T for four courses, both before and after mastectomy. The overall clinical objective remission rate for induction treatment was similar (71% with CMF and 64% with CMF + T). The time to progression or recurrence of the disease was also not significantly different between the two groups. Overall survival was shorter after CMF + T treatment (median value of 41.5 months) than after CMF treatment alone (median value of 79.7 months; p = 0.05). Even after progression or recurrence, survival was shorter for patients receiving CMF + T than those receiving CMF (median values of 7.5 and 17.3 months, respectively; p = 0.09). These results show that the addition of T to CMF in the treatment of locally advanced breast carcinoma, before and after mastectomy, offers no advantage for improving the overall response rate. Moreover, this addition may have an adverse impact on survival in this disease setting.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Neoplasias da Mama/análise , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Receptores de Estrogênio/análise , Indução de Remissão , Tamoxifeno/administração & dosagem , Fatores de Tempo
17.
Tumori ; 75(6): 576-9, 1989 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-2559525

RESUMO

From April 1982 to December 1987, 71 patients with small cell lung cancer entered a randomized clinical trial, and underwent bone marrow biopsy (BMB) as part of staging procedures. We identified 8 patients (11%) with bone marrow metastases, 6 with extensive disease independently of BMB, and 2 with extensive disease on the basis of the BMB only. BMB determined a change in the stage in only 3% (2/71) of the cases. No differences were found in the hematological parameters of the patients with or without bone marrow metastases. The median survival of the patients with bone marrow involvement was the same (41 weeks) as those with extensive disease but without bone marrow involvement. We conclude that unilateral BMB without aspiration detects a substantial proportion of bone marrow metastases in patients with extensive disease. This fact does not worsen the prognosis. A small proportion of patients with apparently limited disease has bone marrow involvement. The technique therefore contributes, to a small extent, to the definition of the clinical stage of the disease. However, bone marrow involvement is an important data of natural history, and therefore new methods to better assess this peculiar site of the disease are needed.


Assuntos
Medula Óssea/patologia , Carcinoma de Células Pequenas/patologia , Neoplasias Pulmonares/patologia , Adulto , Idoso , Carcinoma de Células Pequenas/mortalidade , Carcinoma de Células Pequenas/secundário , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
Cancer ; 61(5): 1041-5, 1988 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-3338048

RESUMO

The value of bone marrow biopsy (BMB) in advanced breast cancer at the time of first relapse was studied in a prospective manner. Bone marrow biopsy was performed in 142 consecutive unselected metastatic patients: 129 at the time of first recurrence, and 13 in patients with metastases at the time of first diagnosis. Overall, BMB was positive in 32 patients (23%). In the group with negative bone x-ray, it was positive in two patients of 84 (2%); both of them had doubtful scan. In the group with positive x-ray, BMB resulted positive in 30 of 58 (52%). There was a significant correlation between number of bone segments radiologically involved and BMB positivity rate, ranging from 15% in the patients with only one, to 68% in those with more than three sites involved (P = 0.02). Patients with x-ray evidence of metastases in the pelvis had significantly higher rate of BMB positivity (67% versus 32%; P = 0.02). The median survival time from the first relapse was 153 weeks in BMB-negative cases and 149 in positive ones. Considering only the patients with demonstration of bone invasion obtained with either or both x-ray and BMB, 34/62 patients had positive BMB (55%). In these cases BMB was found more often positive in patients 50 years or younger than in patients older than 50 years (80% versus 47%; P = 0.05); the median survival time was longer, but not significantly, in BMB-positive patients than in negative ones (149 weeks versus 119; P = 0.3). The authors conclude that BMB is not required in common restaging procedure when both bone survey and scan are negative. Bone marrow biopsy results are more often positive in younger patients and survival is not negatively affected by bone marrow invasion as diagnosed by BMB.


Assuntos
Medula Óssea/patologia , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Biópsia , Neoplasias Ósseas/diagnóstico , Feminino , Humanos , Menopausa , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias/métodos , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos
19.
J Biomol Struct Dyn ; 5(4): 803-17, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3271490

RESUMO

The crystal-state preferred conformation of the terminally blocked hepta- and octapeptides with the general formula -(Aib)n L-Leu-(Aib)2- (n = 4 and 5, respectively), determined by X-ray diffraction, was found to be a right-handed 3(10)-helix stabilized by five and six consecutive intramolecular NH...O = C H-bonds of the C(10)-III type, respectively. The octapeptide structure represents the first observation at atomic resolution of a regular, chiral 3(10)-helix larger than two complete turns. In both cases the right handed screw sense of the helix is dictated by the presence of the single, internal L-residue. This study confirms the propensity of short peptides rich in Aib, the prototype of the amino acid residues dialkylated at the alpha carbon, to adopt a 3(10)-helical structure and is expected to help our understanding of the conformational preferences of the membrane-active, channel-forming, ion-transporting peptaibol antibiotics.


Assuntos
Peptídeos , Butiratos/síntese química , Ligação de Hidrogênio , Leucina/análogos & derivados , Leucina/síntese química , Modelos Moleculares , Peptídeos/síntese química , Conformação Proteica , Difração de Raios X
20.
Cancer ; 61(1): 96-8, 1988 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-3334955

RESUMO

Bone marrow biopsies (BMB) were performed in 173 consecutive unselected breast cancer patients at the time of diagnosis to define the value of this diagnostic tool in the initial staging of mammary carcinoma. In a group of 160 patients with a negative standard staging work-up, BMB was positive in two (1%). Both of them had negative x-ray but bone scan was positive in one and doubtful in the other. Bone marrow biopsy was positive in 31% of 13 additional patients with metastatic disease and in 44% of the nine among them with radiologically involved skeleton. These results exclude that BMB is able to discover micrometastatic foci of neoplastic disease. Its positivity appears strictly correlated with that of bone x-ray and scan. Based on the results of this prospective study, BMB is not required when both bone survey and scan are negative, but could be useful in clarifying diagnostic doubts of skeletal involvement.


Assuntos
Medula Óssea/patologia , Neoplasias da Mama/patologia , Adulto , Biópsia , Osso e Ossos/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Radiografia
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