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1.
Eur Child Adolesc Psychiatry ; 29(2): 227-238, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31302773

RESUMO

Despite the occurrence of several earthquakes, only a few studies were conducted in Italy on the psychological impact in children and adolescents, with data mostly collected within one year after the disaster. This cross-sectional study aimed at exploring the prevalence of both post-traumatic stress disorder (PTSD) and emotional/behavioral difficulties, as well as at identifying their main predictors, among youths 2 years after the earthquake that hit Northern Italy in 2012. 682 children and adolescents (9-14 years) living in two districts (earthquake zone vs control zone) were administered an exposure questionnaire, the UCLA PTSD-Index for DSM-IV, and the Strengths and Difficulties Questionnaire (SDQ) and 1162 parents were assessed through the Symptom Checklist-90 (SCL-90). The prevalence of a likely PTSD in the earthquake zone was 1.9% (4.4% near the epicenter) and the total PTSD score in the affected area was significantly higher than in the control zone. 14.9% of youths living in the earthquake zone had a borderline/abnormal SDQ total difficulties score and 87.5% of youth with a likely PTSD also had a SDQ total score in the borderline/abnormal range. Regression analysis showed that the number of lifetime traumatic events (e.g., death of a relative) was the best predictor of children/adolescents psychological difficulties 2 years after the earthquake, followed by severity of exposure (personal injuries and losses) and parental psychopathology. Despite some limitations, this study highlights that youths may exhibit PTSD symptoms years after disasters, often in comorbidity with behavioral/emotional difficulties, stressing the need for long-term surveillance and interventions in exposed populations.


Assuntos
Terremotos/mortalidade , Psicopatologia/métodos , Transtornos de Estresse Pós-Traumáticos/psicologia , Adolescente , Criança , Estudos Transversais , Feminino , História do Século XXI , Humanos , Itália/epidemiologia , Masculino , Inquéritos e Questionários , Fatores de Tempo
2.
Breast ; 29: 90-5, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27476083

RESUMO

PURPOSE: To evaluate toxicity in breast cancer patients treated with anthracycline and taxane based chemotherapy and whole breast hypofractionated radiotherapy, and to identify the risk factors for toxicity. METHODS AND MATERIALS: 537 early breast cancer patients receiving hypofractionated radiotherapy after conservative surgery were enrolled from April 2009 to December 2014, in an Italian cancer institute. The dose was 42.4 Gy in 16 daily fractions, 2.65 Gy per fraction. The boost to the tumor bed was administered only in grade III breast cancer patients and in patients with close or positive margins. Acute and late toxicity were prospectively assessed during and after radiotherapy according to RTOG scale. The impact of patients clinical characteristics, performed treatments and dose inhomogeneities on the occurrence of an higher level of acute skin toxicity and late fibrosis has been evaluated by univariate and multivariate analysis. RESULTS: The mean age was 74 (range 46-91 yrs). 27% of patients received boost. 22% of cases (n = 119) received also chemotherapy. The median follow-up was 32 months. G1 and G2/G3 acute skin toxicity were 61.3% and 20.5% and G1 and G2/G3 late fibrosis 12.6% and 4.3% respectively. Chemotherapy (p = 0.04), diabetes (p = 0.04) and boost administration (p < 0.01) were found to be statistically significant on the occurrence of late fibrosis, but a multivariate analysis did not show any factors connected. The boost administration (p < 0.01), the breast volume (p = 0.05), dose inhomogeneities (p < 0.01) and boost volume (p = 0.04) were found to be statistically significant as concerns the occurrence of acute skin reaction at the univariate analysis, but only the boost administration (p = 0.02), at multivariate analysis. CONCLUSIONS: The results of our study, according to the large randomized trials, confirmed that hypofractionated whole breast irradiation is safe, and only the boost administration seems to be an important predictor for toxicity. Chemotherapy does not impact on acute and late skin toxicity.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias da Mama/terapia , Quimiorradioterapia Adjuvante/efeitos adversos , Hipofracionamento da Dose de Radiação , Lesões por Radiação/etiologia , Idoso , Idoso de 80 Anos ou mais , Antraciclinas/efeitos adversos , Mama/patologia , Mama/efeitos da radiação , Neoplasias da Mama/patologia , Hidrocarbonetos Aromáticos com Pontes/efeitos adversos , Relação Dose-Resposta à Radiação , Feminino , Fibrose , Seguimentos , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Estudos Prospectivos , Reirradiação/efeitos adversos , Fatores de Risco , Pele/efeitos da radiação , Taxoides/efeitos adversos
3.
Chem Commun (Camb) ; 51(27): 5917-20, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25730473

RESUMO

Bacterial biosensors are simple, cost-effective and efficient analytical tools for detecting bioavailable heavy metals in the environment. This work presents the design, construction and calibration of a novel whole-cell fluorescent biosensory device that, simultaneously and with high sensitivity, reports the presence of toxic mercury, lead, cadmium and/or gold ions in aqueous samples. This bio-reporter can be easily applied as an immediate alerting tool for detecting the presence of harmful pollutants in drinking water.


Assuntos
Técnicas Biossensoriais/métodos , Cádmio/análise , Água Potável/química , Ouro/análise , Chumbo/análise , Mercúrio/análise , Poluentes Químicos da Água/análise , Sequência de Bases , Cátions Bivalentes , Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Dados de Sequência Molecular , Plasmídeos/química , Plasmídeos/metabolismo , Regiões Promotoras Genéticas , Salmonella enterica/genética , Salmonella enterica/metabolismo
4.
Cell ; 103(1): 113-25, 2000 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-11051552

RESUMO

Iron is essential for all organisms but can be toxic in excess. Iron homeostasis is typically regulated by cytoplasmic iron binding proteins, but here we describe a signal transduction system (PmrA/PmrB) that responds to extracytoplasmic ferric iron. Iron promoted transcription of PmrA-activated genes and resistance to the antibiotic polymyxin in Salmonella. The PmrB protein bound iron via its periplasmic domain which harbors two copies of the sequence ExxE, a motif present in the Saccharomyces FTR1 iron transporter and in mammalian ferritin light chain. A pmrA mutant was hypersensitive to killing by iron but displayed wild-type resistance to a variety of oxidants, suggesting PmrA/PmrB controls a novel pathway mediating the avoidance of iron toxicity.


Assuntos
Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Espaço Extracelular/metabolismo , Ferro/metabolismo , Ferro/farmacologia , Salmonella enterica/efeitos dos fármacos , Transdução de Sinais/fisiologia , Proteínas de Bactérias/genética , Sítios de Ligação/efeitos dos fármacos , Sítios de Ligação/genética , Resistência Microbiana a Medicamentos/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/genética , Proteínas de Ligação ao Ferro , Fenótipo , Polimixinas/farmacologia , Estrutura Terciária de Proteína/genética , Salmonella enterica/genética , Salmonella enterica/metabolismo , Fatores de Transcrição/genética , Transcrição Gênica/genética , Proteínas de Ligação a Transferrina
5.
J Bacteriol ; 182(13): 3874-6, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10851011

RESUMO

The Salmonella PmrA-PmrB system controls the expression of genes necessary for polymyxin B resistance. Four loci were previously identified as part of the regulon, and interaction of PmrA with the promoter region of three of them was observed. Here we characterized the interaction of PmrA with the promoter region of ugd, previously suggested to be regulated indirectly by PmrA. Our results indicate that PmrA controls the expression of ugd by interacting with a specific sequence in the promoter region of this gene.


Assuntos
Proteínas de Bactérias/metabolismo , Regiões Promotoras Genéticas , Salmonella enterica/enzimologia , Uridina Difosfato Glucose Desidrogenase/genética , Proteínas de Bactérias/genética , Sequência de Bases , Sítios de Ligação , DNA Bacteriano , Dados de Sequência Molecular , Fosforilação , Salmonella enterica/genética
6.
J Biol Chem ; 275(30): 22948-54, 2000 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-10807931

RESUMO

The PhoP/PhoQ two-component system controls the expression of essential virulence traits in the pathogenic bacterium Salmonella enterica serovar Typhimurium. Environmental deprivation of Mg(2+) activates the PhoP/PhoQ signal transduction cascade, which results in an increased expression of genes necessary for survival inside the host. It was previously demonstrated that the interaction of Mg(2+) with the periplasmic domain of PhoQ promotes a conformational change in the sensor protein that leads to the down-regulation of PhoP-activated genes. We have now examined the regulatory effect of Mg(2+) on the putative activities of the membrane-bound PhoQ. We demonstrated that Mg(2+) promotes a phospho-PhoP phosphatase activity in the sensor protein. This activity depends on the intactness of the conserved His-277, suggesting that the phosphatase active site overlaps the H box. The integrity of the N-terminal domain of PhoQ was essential for the induction of the phosphatase activity, because Mg(2+) did not stimulate the release of inorganic phosphate from phospho-PhoP in a fusion protein that lacks this sensing domain. These findings reveal that the sensor PhoQ harbors a phospho-PhoP phosphatase activity, and that this phosphatase activity is the target of the extracellular Mg(2+)-triggered regulation of the PhoP/PhoQ system.


Assuntos
Proteínas de Bactérias/metabolismo , Magnésio/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Salmonella enterica/metabolismo , Sequência de Bases , Primers do DNA , Fosforilação , Salmonella enterica/enzimologia
7.
Am J Clin Oncol ; 23(1): 18-21, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10683067

RESUMO

Radiotherapy (RT) in patients with favorable-stage Hodgkin's disease can induce clinical and subclinical evidence of pulmonary damage lasting over the years. In this study, we monitored 36 patients with stage IA-IIA Hodgkin's disease treated with subtotal nodal RT. The planned dose of RT was 40 Gy to 44 Gy to the involved areas and 36 Gy to the adjacent uninvolved areas. Pulmonary function was evaluated by chest radiograph, spirometric parameters, arterial blood gas analysis, and single-breath CO transfer factor (DLCO). The tests were performed before and at the end of irradiation, and during the follow-up 1 and 3 to 5 years after the treatment. At the end of RT, we found a significant decrease of total lung capacity, vital capacity, forced expiratory volume in 1 second, residual volume, and DLCO. Spirometric parameters improved during the follow-up period, whereas the decline of DLCO (-6.4%) was persistent. No correlation was found between mantle RT dose and DLCO changes. Four patients showed a decline of DLCO of >20% from pretreatment values but only one was symptomatic. Our study confirms that RT induces a pulmonary-restrictive disease at a subclinical level that seems to be reversible in the majority of patients.


Assuntos
Doença de Hodgkin/radioterapia , Pneumonite por Radiação , Adolescente , Adulto , Idoso , Feminino , Doença de Hodgkin/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pneumonite por Radiação/diagnóstico , Pneumonite por Radiação/fisiopatologia , Dosagem Radioterapêutica , Indução de Remissão , Testes de Função Respiratória
8.
Cancer J Sci Am ; 5(5): 275-82, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10526668

RESUMO

PURPOSE: This pilot study was conducted to evaluate the efficacy and toxicity of a new intensive drug regimen, combined with involved-nodal-field radiotherapy, in advanced Hodgkin's disease not treated by chemotherapy. PATIENTS AND METHODS: From September 1990 to March 1993, 73 evaluable patients with newly diagnosed stage IIB, III (A and B), and IV (A and B) Hodgkin's disease or who were relapsing after primary subtotal or total nodal irradiation were treated with eight cycles of etoposide, epirubicin, bleomycin, cyclophosphamide, and prednisolone (VEBEP) followed by radiotherapy (30-36 Gy) to the nodal site or sites of pretreatment disease. The median duration of follow-up was 68 months. RESULTS: The complete remission rate was 94% (95% CI: 86-98). At 6 years, freedom from progression and overall survival rates were 78% (95% CI: 68-88) and 82% (95% CI: 73-91), respectively. There was one episode of fatal sepsis after bone marrow aplasia that occurred after VEBEP and extended-field irradiation. Hematologic toxicity during chemotherapy was acceptable; without the support of growth factors, grade IV leukopenia and grade IV neutropenia, as determined within cycles, occurred in 38% and 85% of patients, respectively, but was reversible in the vast majority of patients by the day of treatment recycle. No episodes of epidoxorubicin-related cardiomyopathy or symptomatic pulmonary toxicity were documented. Overt and/or subclinical hypothyroidism occurred in 38% of cases. Gonadal damage was evident in the large majority of male patients but reversible in half of them, whereas permanent sterility was observed in females at least 35 years of age. No secondary leukemia has been so far detected. DISCUSSION: VEBEP followed by involved-nodal-field radiotherapy is an effective treatment for chemotherapy-naive Hodgkin's disease and is associated to acceptable rates of acute and intermediate-term toxicity. This intensive regimen, which does not routinely require the support of hematopoietic growth factors and can be delivered in an outpatient setting, warrants a prospective comparison in a randomized trial versus one of the more effective standard-combination regimens.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/radioterapia , Adolescente , Adulto , Bleomicina/administração & dosagem , Terapia Combinada , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Epirubicina/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Prednisona/administração & dosagem , Indução de Remissão , Fatores de Tempo , Resultado do Tratamento
9.
Br J Haematol ; 103(2): 533-5, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9827930

RESUMO

Twenty-six patients with relapsed or refractory Hodgkin's disease (HD) were treated with an intensive salvage regimen combining ifosfamide (3000 mg/m2/d, days 1-4 through continuous intravenous infusion) and vinorelbine (25 mg/m2, i.v. days 1 and 5) with mesna uroprotection and G-CSF support. Courses were given at 3-week intervals. Ten patients achieved a complete and 10 patients a partial response, yielding an overall response rate of 77%. The main toxic effect was neutropenia and the combination was well tolerated.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doença de Hodgkin/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Feminino , Humanos , Ifosfamida/administração & dosagem , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Projetos Piloto , Recidiva , Terapia de Salvação , Resultado do Tratamento , Vimblastina/administração & dosagem , Vimblastina/análogos & derivados , Vinorelbina
10.
J Bacteriol ; 179(22): 7040-5, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9371451

RESUMO

The PmrA-PmrB two-component system of Salmonella typhimurium controls resistance to the peptide antibiotic polymyxin B and to several antimicrobial proteins from human neutrophils. Amino acid substitutions in the regulatory protein PmrA conferring resistance to polymyxin lower the overall negative charge of the lipopolysaccharide (LPS), which results in decreased bacterial binding to cationic polypeptides and increased bacterial survival within human neutrophils. We have now identified three PmrA-activated loci that are required for polymyxin resistance. These loci were previously shown to be necessary for growth on low-Mg2+ solid media, indicating that LPS modifications that mediate polymyxin resistance are responsible for the adaptation to Mg2+-limited environments. Conditions that promote transcription of PmrA-activated genes--growth in mildly acidic pH and micromolar Mg2+ concentrations--increased survival in the presence of polymyxin over 16,000-fold in a wild-type organism but not in a mutant lacking pmrA. Our experiments suggest that low pH and low Mg2+ concentrations may induce expression of PmrA-activated genes within phagocytic cells and promote bacterial resistance to host antimicrobial proteins. We propose that the LPS is a Mg2+ reservoir and that the PmrA-controlled LPS modifications neutralize surface negative charges when Mg2+ is transported into the cytoplasm during growth in Mg2+-limited environments.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Resistência Microbiana a Medicamentos , Magnésio/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Alelos , Antibacterianos/farmacologia , Proteínas de Bactérias/fisiologia , Regulação Bacteriana da Expressão Gênica , Concentração de Íons de Hidrogênio , Lipopolissacarídeos/metabolismo , Testes de Sensibilidade Microbiana , Peptídeos/metabolismo , Polimixinas/farmacologia , Ligação Proteica , Salmonella typhimurium/metabolismo , Transcrição Gênica
11.
J Clin Oncol ; 15(2): 528-34, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9053474

RESUMO

PURPOSE: This study analyzed long-term results in patients with Hodgkin's disease who were resistant to or relapsed after first-line treatment with MOPP and ABVD. Response to salvage treatments and prognostic factors were also evaluated. PATIENTS AND METHODS: The study population included 115 refractory or relapsed patients among a total of 415 patients treated with alternating or hybrid MOPP-ABVD followed by radiotherapy (25 to 30 Gy) to initial bulky sites. The median follow-up duration of the present series was 91 months. Thirty-nine of 115 patients (34%) showed disease progression while on primary treatment (induction failures); 48 relapsed after complete remissions that lasted < or = 12 months and 28 after complete remission that lasted more than 12 months from the end of all treatments. RESULTS: At 8 years, the overall survival rate was 27%, being 54% and 28% in patients whose initial complete remission was longer or shorter than 12 months, respectively, and 8% in induction failures (P < .001). Response to first-line chemotherapy and disease extent at first progression significantly influenced long-term results, as well as the incidence and duration of complete remission. CONCLUSION: The present data confirm previous observations that showed the main prognostic factors to influence outcome after salvage treatment are response duration to first-line therapy and disease extent at relapse. The results indicate that patients who relapse after the alternating MOPP/ABVD regimen have a prognosis similar to that of patients who relapse after a four-drug regimen (MOPP or ABVD alone). Re-treatment with initial chemotherapy seems the treatment of choice for patients who relapse after an initial complete remission that lasts greater than 12 months, while the real impact of high-dose chemotherapy or new regimens should be assessed in resistant patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doença de Hodgkin/tratamento farmacológico , Adulto , Bleomicina/administração & dosagem , Dacarbazina/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Humanos , Masculino , Mecloretamina/administração & dosagem , Valor Preditivo dos Testes , Prednisona/administração & dosagem , Procarbazina/administração & dosagem , Prognóstico , Terapia de Salvação , Análise de Sobrevida , Falha de Tratamento , Resultado do Tratamento , Vimblastina/administração & dosagem , Vincristina/administração & dosagem
12.
J Bacteriol ; 178(23): 6796-801, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8955299

RESUMO

The PhoP/PhoQ two-component system of Salmonella typhimurium governs transcription of some 25 loci in response to the extracellular concentration of Mg2+. We have now identified one of these loci as pmrCAB, which codes for a two-component system that mediates resistance to the antibiotic polymyxin B. Transcription of seven of 25 PhoP-activated loci was dependent on a functional PmrA protein, the response regulator of the PmrA/PmrB system. Expression of the PmrA-dependent loci was induced by either Mg2+ limitation or mild acidification, whereas transcription of a PmrA-independent gene was activated by Mg2+ limitation but not acid pH. Induction of PmrA-activated genes by Mg2 limitation required the PhoP and PhoQ proteins. In contrast, the acid-mediated activation of PmrA-regulated genes occurred in strains that were missing either one of these proteins. Transcriptional regulation by a cascade of two-component systems allows pathogenic bacteria to express their virulence determinants in response to a broader spectrum of environmental cues.


Assuntos
Proteínas de Bactérias/fisiologia , Regulação Bacteriana da Expressão Gênica , Salmonella typhimurium/genética , Fatores de Transcrição/fisiologia , Proteínas de Bactérias/genética , Meios de Cultura , Concentração de Íons de Hidrogênio , Magnésio/farmacologia , Mutagênese Insercional , Óperon , Salmonella typhimurium/metabolismo , Salmonella typhimurium/patogenicidade , Fatores de Transcrição/genética
13.
J Bacteriol ; 178(17): 5092-9, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8752324

RESUMO

The PhoP-PhoQ two-component system is essential for virulence in Salmonella typhimurium. This system controls expression of some 40 different proteins, yet most PhoP-regulated genes remain unknown. To identify PhoP-regulated genes, we isolated a library of 50,000 independent lac gene transcriptional fusion strains and investigated whether production of beta-galactosidase was regulated by PhoP. We recovered 47 lac gene fusions that were activated and 7 that were repressed when PhoP was expressed. Analysis of 40 such fusions defined some 30 loci, including mgtA and mgtCB, which encode two of the three Mg2+ uptake systems of S. typhimurium; ugd, encoding UDP-glucose dehydrogenase; phoP, indicative that the phoPQ operon is autoregulated; and an open reading frame encoding a protein with sequence similarity to VanX, a dipeptidase required for resistance to vancomycin. Transcription of PhoP-activated genes was regulated by the levels of Mg2+ in a PhoP-dependent manner. Strains with mutations in phoP or phoQ were defective for growth in low-Mg2+ media. The mgtA and mgtCB mutants reached lower optical densities than the wild-type strain in low-Mg2+ liquid media but displayed normal growth on low-Mg2+ solid media. Six PhoP-activated genes were identified as essential to form colonies on low-Mg'+ solid media. Cumulatively, our experiments establish that the PhoP-PhoQ system governs the adaptation to magnesium-limiting environments.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Transporte de Cátions , Regulação Bacteriana da Expressão Gênica , Magnésio/metabolismo , Proteínas de Membrana Transportadoras , Salmonella typhimurium/genética , Fatores de Transcrição/metabolismo , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Mapeamento Cromossômico , Sequências Reguladoras de Ácido Nucleico , Regulon , Salmonella typhimurium/metabolismo
14.
Proc Natl Acad Sci U S A ; 93(15): 7800-4, 1996 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-8755556

RESUMO

We have identified a region unique to the Salmonella typhimurium chromosome that is essential for virulence in mice. This region harbors at least three genes: two (spiA and spiB) encode products that are similar to proteins found in type III secretion systems, and a third (spiR) encodes a putative regulator. A strain with a mutation in spiA was unable to survive within macrophages but displayed wild-type levels of epithelial cell invasion. The culture supernatants of the spi mutants lacked a modified form of flagellin, which was present in the supernatant of the wild-type strain. This suggests that the Spi secretory apparatus exports a protease, or a protein that can alter the activity of a secreted protease. The "pathogenicity island" harboring the spi genes may encode the virulence determinants that set Salmonella apart from other enteric pathogens.


Assuntos
Proteínas de Bactérias/genética , Genes Bacterianos , Macrófagos/microbiologia , Salmonella typhimurium/genética , Salmonella typhimurium/patogenicidade , Virulência/genética , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/química , Linhagem Celular , Sobrevivência Celular , Endopeptidases/metabolismo , Flagelina/genética , Macrófagos/citologia , Camundongos , Dados de Sequência Molecular , Mutação , Salmonella typhimurium/crescimento & desenvolvimento , Homologia de Sequência de Aminoácidos
15.
J Clin Oncol ; 14(5): 1421-30, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8622055

RESUMO

PURPOSE: To compare, in a prospective randomized trial, the efficacy of two different sequences of mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) and doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) chemotherapy in untreated advanced Hodgkin's disease. PATIENTS AND METHODS: From June 1982 to September 1990, 427 consecutive previously untreated patients with pathologic stage IB, IIA bulky, IIB, III (A and B), and IV (A and B) disease were prospectively randomized to receive two different sequences of MOPP and ABVD for a minimum of six cycles followed by radiotherapy (median dose, 30 Gy) to the nodal site(s) of pretreatment bulky disease. Of 415 assessable patients, 211 received one cycle of MOPP monthly, alternated with one cycle of ABVD (alternating regimen), and 204 patients received one-half cycle of MOPP alternated with one-half cycle of ABVD within a 1-month period (hybrid regimen). RESULTS: The complete remission (CR) rate was 91% with the alternating regimen and 89% with the hybrid regimen. At 10 years, the freedom-from-progression (FFP) rate was 67% versus 69% and the overall survival (OS) rate was 74% versus 72%, respectively. After attainment of CR, 85 patients relapsed in nodal (n = 60) versus extranodal with or without nodal (n = 25) sites. In patients given consolidative radiation because of bulky lymphoma, the true recurrence rate was 13%. A total of 23 second malignancies (6%) were documented, including 11 cases of acute nonlymphocytic leukemia. No cases of congestive heart failure attributable to doxorubicin or pulmonary toxicity related to bleomycin were documented. CONCLUSION: By delivering MOPP and ABVD, it is possible to cure approximately 70% of patients with advanced Hodgkin's disease. The two different drug sequences yielded superimposable results.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doença de Hodgkin/tratamento farmacológico , Adolescente , Adulto , Idoso , Bleomicina/administração & dosagem , Terapia Combinada , Dacarbazina/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Doença de Hodgkin/patologia , Doença de Hodgkin/radioterapia , Humanos , Masculino , Mecloretamina/administração & dosagem , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Procarbazina/administração & dosagem , Estudos Prospectivos , Indução de Remissão , Terapia de Salvação , Vimblastina , Vincristina/administração & dosagem
16.
Cell ; 84(1): 165-74, 1996 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-8548821

RESUMO

Ions are not traditionally thought to act as first messengers in signal transduction cascades. However, while searching for genes regulated by the PhoP/PhoQ virulence regulatory system of Salmonella typhimurium, we recovered two loci whose expression is controlled by the concentration of Mg2+. To determine whether Mg2+ is the signal modulating the whole PhoP/PhoQ system, we evaluated the gene expression pattern of six PhoP-activated genes. Growth in physiological concentrations of divalent cations repressed transcription of PhoP-activated genes and rendered wild-type Salmonella phenotypically PhoP-. Mg2+ changed the conformation of the periplasmic domain of PhoQ, identifying this protein as a Mg2+ sensor. A mutation in the sensing domain of PhoQ altered the set point for Mg2+ and rendered Salmonella avirulent.


Assuntos
Magnésio/farmacologia , Salmonella typhimurium/fisiologia , Salmonella typhimurium/patogenicidade , Transdução de Sinais/fisiologia , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Sequência de Bases , Cátions/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Concentração de Íons de Hidrogênio , Cinética , Dados de Sequência Molecular , Mutação/fisiologia , Peptídeos/fisiologia , Fenótipo , Conformação Proteica , Sensibilidade e Especificidade , Fatores de Transcrição/genética , Virulência
17.
J Bacteriol ; 177(15): 4364-71, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7543474

RESUMO

The Salmonella typhimurium PhoP-PhoQ two-component regulatory system controls the expression of several genes, some of which are necessary for virulence. During a screening for PhoP-regulated genes, we identified the phoPQ operon as a PhoP-activated locus. beta-Galactosidase activity originating from phoPQ-lac transcriptional fusions required the presence of both the transcriptional regulator PhoP and its cognate sensor-kinase PhoQ. At low concentrations, PhoQ stimulated expression of phoPQ-lac transcriptional fusions. However, larger amounts of PhoQ protein without a concomitant increase in PhoP failed to activate phoPQ-lac fusions. Two different transcripts are produced from the phoPQ operon during exponential growth. These transcripts define two promoters: phoPp1, which requires both PhoP and PhoQ for activity and which is environmentally regulated, and phoPp2, which remains active in the absence of PhoP and PhoQ but which is slightly stimulated by these proteins. The pattern of transcriptional autoregulation was also observed at the protein level with anti-PhoP antibodies. In sum, autoregulation of the phoPQ operon provides several levels of control for the PhoP-PhoQ regulon. First, environmental signals would stimulate PhoQ to phosphorylate the PhoP protein that is produced at basal levels from the PhoP-PhoQ-independent promoter. Then, phospho-PhoP would activate transcription of phoPp1, resulting in larger amounts of PhoP and PhoQ and increased expression of PhoP-activated genes. A return to basal levels could be mediated by a posttranscriptional mechanism by which translation of the mRNA produced from phoPp1 is inhibited.


Assuntos
Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica/fisiologia , Óperon , Salmonella typhimurium/genética , Transcrição Gênica/fisiologia , Proteínas de Bactérias/biossíntese , Sequência de Bases , Clonagem Molecular , Elementos de DNA Transponíveis , Homeostase/genética , Óperon Lac , Modelos Genéticos , Dados de Sequência Molecular , Mutação , Conformação de Ácido Nucleico , Regiões Promotoras Genéticas , RNA Bacteriano/genética , RNA Mensageiro/análise , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética
18.
Tumori ; 81(4): 265-7, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8540124

RESUMO

To investigate the relation between estrogen receptor (ER) status and timing of relapse, we retrospectively studied two groups of patients (200 cases in each group) who underwent radical mastectomy and developed an early relapse (within 3 years of the surgery) or a long-term relapse (more than 8 years after surgery). One-hundred and eighty-two (91%) patients who developed a long-term relapse were ER-positive (ER+), whereas only 64% of patients who developed an early relapse were ER+ (P < 0.001), supporting the hypothesis that a long-term relapse is more frequently associated with an ER+ tumor. A review of the literature, which indicated that a long-term relapse arises more frequently in patients in whom a partial hormone control is maintained, seems to support this finding, albeit the presence of 18 ER-negative (ER-) cases in our study. However, this apparent contradictory observation could be explained by the fact that 12 of our patients were in premenopause and that ER-status could have been false ER- results due to the binding of endogenous estradiol to ER.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/ultraestrutura , Receptores de Estrogênio/análise , Neoplasias da Mama/cirurgia , Feminino , Humanos , Valor Preditivo dos Testes , Pré-Menopausa , Prognóstico , Recidiva , Fatores de Tempo
19.
Int J Radiat Oncol Biol Phys ; 30(4): 813-9, 1994 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-7525516

RESUMO

PURPOSE: The study was undertaken to evaluate the long-term results in a favorable subset of patients with pathological Stage IA-IIA treated with irradiation alone. METHODS AND MATERIALS: One hundred and forty-seven adults with laparotomy- Staged IA-IIA "favorable" Hodgkin's disease were treated with primary subtotal nodal irradiation. Patients with infradiaphragmatic presentation were irradiated through paraortic and inguino-iliac node chains (inverted Y field) followed by prophylactic mediastinal and supraclavicular fields. RESULTS: Actuarial overall survival (OS) at 7 years (median follow-up 77 months) was: 93% for the whole series, 94% for Stage I, and 92% for Stage II. The freedom from first progression (FFP) (80% for the whole series) showed a statistically significant difference (p = 0.008) between Stage I (88%) and Stage II (71%). By univariate analysis, stage alone had an independent prognostic significance for OS and FFP. Of the 29 relapsed patients, 8 were previously classified as Stage I and 21 as Stage II; 16 of 29 (55%) of the relapses occurred in the pelvis and 9 in extranodal sites. After salvage treatment with chemotherapy all patients achieved a second complete remission. Seven second malignancies (two acute nonlymphocytic leukemias, one preleukemic syndrome, and four solid tumors) have been detected so far. Hypothyroidism was observed in 16% of patients and a reversible pulmonary restrictive syndrome in 14% of cases, respectively. CONCLUSIONS: Within 7 years from radiation therapy, about one-quarter of the patients with Stage II disease will experience a relapse and need intensive salvage chemotherapy. This is not invariably successful and safe, for it may be complicated by either acute or potentially fatal long-term adverse effects, such as second malignancies and cardiac or pulmonary sequelae, in about 5% of patients. The high frequency of relapse in Stage IIA patients suggests a combined modality approach with relatively short-term chemotherapy not including alkylating agents.


Assuntos
Doença de Hodgkin/patologia , Doença de Hodgkin/radioterapia , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bleomicina/administração & dosagem , Terapia Combinada , Ciclofosfamida/administração & dosagem , Dacarbazina/administração & dosagem , Doxorrubicina/administração & dosagem , Epirubicina/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Seguimentos , Doença de Hodgkin/complicações , Humanos , Masculino , Mecloretamina/administração & dosagem , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Segunda Neoplasia Primária/patologia , Prednisona/administração & dosagem , Procarbazina/administração & dosagem , Prognóstico , Fatores de Risco , Terapia de Salvação , Vimblastina , Vincristina/administração & dosagem
20.
Int J Syst Bacteriol ; 44(3): 527-33, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7520741

RESUMO

The essential GroEL proteins represent a subset of molecular chaperones ubiquitously distributed among species of the eubacterial lineage, as well as in eukaryote organelles. We employed these highly conserved proteins to infer eubacterial phylogenies. GroEL from the species analyzed clustered in distinct groups in evolutionary trees drawn by either the distance or the parsimony method, which were in general agreement with those found by 16S rRNA comparisons (i.e., proteobacteria, chlamydiae, bacteroids, spirochetes, firmicutes [gram-positive bacteria], and cyanobacteria-chloroplasts). Moreover, the analysis indicated specific relationships between some of the aforementioned groups which appeared not to be clearly defined or controversial in rRNA-based phylogenetic studies. For instance, a monophyletic origin for the low-G+C and high-G+C subgroups among the firmicutes, as well as their specific relationship to the cyanobacteria-chloroplasts, was inferred. The general observations suggest that GroEL proteins provide valuable evolutionary tools for defining evolutionary relationships among the eubacterial lineage of life.


Assuntos
Bactérias/classificação , Bactérias/genética , Proteínas de Bactérias/genética , Evolução Biológica , Proteínas de Choque Térmico/genética , Bactérias/química , Composição de Bases , Chaperonina 60 , Chlamydia/classificação , Chlamydia/genética , Cianobactérias/classificação , Cianobactérias/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Helicobacter pylori/classificação , Helicobacter pylori/genética , Filogenia , Porphyromonas gingivalis/classificação , Porphyromonas gingivalis/genética , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Spirochaetales/classificação , Spirochaetales/genética
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