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1.
J Endocrinol Invest ; 43(5): 663-675, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31786795

RESUMO

PURPOSE: Myotonic dystrophy type 1 (DM1) is a genetic disorder caused by CTG expansion in the DMPK gene. The aim was to investigate the endocrine and metabolic aspects of DM1. PATIENTS AND METHODS: Retrospective, case-control study. We compared pituitary, thyroid, adrenal, gonadal and liver function and glycolipid metabolism of 63 DM1 patients against 100 control subjects. Given age-related differences, 2 further subgroups were created to investigate the pituitary-gonadal axis: < 41 (1a) and ≥ 41 (1b) years old for male subjects and < 46 (2a) and ≥ 46 (2b) years old for female subjects. Testicular and thyroid ultrasounds were also performed in the DM1 group. RESULTS: FT3 and FT4 were significantly lower in DM1 men than controls, while for both males and females, thyroglobulin, ACTH and cortisol were significantly higher in the DM1 group. Gonadotropin levels were significantly higher and inhibin B and DHEA-S levels significantly lower in DM1 patients than controls for both male subgroups. Testosterone and SHBG were significantly higher in controls than in patients for subgroup 1a. Prolactin was significantly higher in patients in subgroups 1b, while testosterone was lower in subgroup 2a than in age-matched female controls. A correlation between the number of CTG repeats and the percentage of male hypogonadal subjects was found. Finally, there was a worse glucose and lipid pattern and significantly higher transaminase and gamma-GT levels in both male and female patients. CONCLUSIONS: The high frequency of endocrine and metabolic abnormalities in DM1 highlights the importance of endocrine monitoring to enable the prompt initiation of a suitable therapy.


Assuntos
Distrofia Miotônica/sangue , Testículo/diagnóstico por imagem , Glândula Tireoide/diagnóstico por imagem , Adolescente , Hormônio Adrenocorticotrópico/sangue , Adulto , Fatores Etários , Idoso , Glicemia , Estudos de Casos e Controles , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hidrocortisona/sangue , Inibinas/sangue , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Distrofia Miotônica/diagnóstico por imagem , Prolactina/sangue , Estudos Retrospectivos , Caracteres Sexuais , Fatores Sexuais , Testosterona/sangue , Tireoglobulina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue , Ultrassonografia , Adulto Jovem
2.
Amino Acids ; 38(1): 103-11, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19067107

RESUMO

In order to develop new oligodeoxyribonucleotide (ODN) analogs to be used in biotechnological applications, we report here the synthesis, characterization and nucleic acid binding studies of novel nucleopeptides, that we called epsilon-lys/gamma-dabPNAs, containing a backbone of alternated L-diaminobutyric acid and L-lysine moieties. Exploring the hybridization properties of the new ODN analog, we found, by circular dichroism and UV spectroscopies, that a homothymine epsilon-lys/gamma-dabPNA hexamer binds both DNA and RNA of complementary sequence. Furthermore, human serum stability assays on the alternate nucleopeptide evidenced a noteworthy degradation resistance. These results encourage us to deepen the knowledge of this analog, in order to evaluate its possible use in antigene/antisense or diagnostic applications.


Assuntos
Oligodesoxirribonucleotídeos/química , Ácidos Nucleicos Peptídicos/química , Peptídeos/química , DNA/química , Humanos , Estrutura Molecular , Hibridização de Ácido Nucleico , Oligodesoxirribonucleotídeos/síntese química , Peptídeos/síntese química , RNA/química
3.
Radiol Med ; 115(6): 975-82, 2010 Sep.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-20352358

RESUMO

PURPOSE: This paper describes an uncommon radiation treatment of the external ear, with ultrasound (US) transmission gel used as bolus device to compensate for the irregularity of the target surface. MATERIALS AND METHODS: Postoperative radiotherapy for cutaneous carcinoma was performed with a single high-energy electron beam directed over the ear auricle. Due to the irregular surface of the target, a "missing tissue" compensator was employed. Daily, after patient positioning, the concha was filled and flattened with US gel, and a dose of 54 Gy in 27 fractions was delivered. RESULTS: Water equivalence of the gel was verified by comparing the gel's computed tomography (CT) number [Hounsfield units (HU)] and density with the corresponding values for water and another commercial bolus device. Whereas ultrasound gel and water had comparable values (HU: 0; density 1 g/cm(3) for both), the corresponding values for the commercial device were slightly higher (HU: 80; density 1.02 g/cm(3)). CONCLUSIONS: Ultrasound gel proved to be an easy, fast and cheap compensating tool. Its water equivalence allows it to be used as an alternative to water, though easier to position and with lower risk of displacement. Thus, it is recommendable as a practical tool for most irregular sites. Further investigations are warranted to validate this solution in more complex irradiation techniques.


Assuntos
Carcinoma/radioterapia , Pavilhão Auricular/efeitos da radiação , Géis , Neoplasias Cutâneas/radioterapia , Humanos , Posicionamento do Paciente , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Resultado do Tratamento , Ultrassom
4.
Ann Ig ; 22(5): 481-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21381543

RESUMO

A short-version (15-week long) of school-based nutrition education program called "Bring Fruit to School" to enhance primary schoolchildren's fruit and vegetable (F&V) intake was evaluated. We recruited 199 primary schoolchildren from 8 classes (grade 2-5). The primary end-point was an increase in the children's F&V intake. The intervention period lasted 15 weeks, and was divided into three phases: weeks 1-5, weeks 6-10 and weeks 11-15. The F&V intake of the schoolchildren was also monitored in a subsequent follow-up period (16th-32nd week). By week 15, 92 (46.2%, P < .001) schoolchildren increase fruit intake and 91 (45.7%, P < .001) increase vegetable intake. The F&V intake increased during the intervention period and was constant in follow-up. The BFtS program is an effective means to promote primary schoolchildren's F&V intake, and was implemented in Italy by the Food and Nutrition Service of Foggia's Local Health Authority. It could be extended to many other countries by local nutrition agencies, such as associations for nutrition.


Assuntos
Dieta , Frutas , Educação em Saúde , Política Nutricional , Verduras , Criança , Humanos , Itália , Fatores de Tempo
5.
Eur Rev Med Pharmacol Sci ; 24(6): 2994-3003, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32271417

RESUMO

OBJECTIVE: To profile and correlate KRAS mutations with outcome in stage III colon cancer (CC) patients who underwent adjuvant chemotherapy following curative resection surgery. PATIENTS AND METHODS: In this retrospective study, eligible patients were those with resected stage III CC who underwent 6-months adjuvant chemotherapy, either with fluoropyrimidine monotherapy (FP) or with oxaliplatin-based regimens (O-FP). Disease-free survival (DFS) and overall survival (OS) were analyzed and computed using the Kaplan-Meier method and the log-rank test. RESULTS: The study population included 148 patients (n=65 FP and n=83 O-FP). We identified KRAS mutations in 41/148 (27%) patients, of which 18 (44%) received FP and 23 (56%) O-FP. Five-year DFS and OS were significantly higher in patients with KRAS wild-type vs. mutant [DFS: 78 vs. 56%, HR: 0.47 (95% CI: 0.25; 0.87), p=0.01; OS: 73 vs. 68%, HR: 0.44 (95% CI: 0.21; 0.88), p=0.01]. In patients treated with FP, the 5-year DFS and OS was significantly improved in the KRAS wild-type vs. mutant group, respectively [DFS: 80 vs. 43%, HR: 2.88 (95% CI: 0.67; 3.76), p=0.014; OS: 85 vs. 68%, HR: 0.27 (95% CI: 0.10; 0.73), p=0.005]. Conversely, 5-year DFS and OS were not statistically different for patients with KRAS wild-type vs. mutations treated with O-FP, respectively [DFS: 78 vs. 65%, HR: 1.59 (95% CI: 0.67; 3.76), p=0.281; OS: 80 vs. 75%, HR: 0.73 (95% CI: 0.55; 2.12), p=0.57)]. CONCLUSIONS: Our results suggest that curatively resected stage III CC patients exhibiting wild-type KRAS status might benefit from FP alone. Conversely, an oxaliplatin-containing regimen should be recommended in KRAS mutated patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/terapia , Proteínas Proto-Oncogênicas p21(ras)/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Endonucleases/genética , Endonucleases/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Estudos Retrospectivos
6.
J Pept Sci ; 12(12): 829-35, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17131297

RESUMO

In the present work, we report the synthesis and the characterization of a new chiral nucleoaminoacid, in which a diaminobutyric moiety is connected to the DNA nucleobase by an amidic bond, and its oligomerization to give the corresponding nucleo-gamma-peptide. The ability of this synthetic polymer to bind complementary DNA was studied in order to explore its possible use in antigene/antisense or diagnostic applications. Our interest in the presented DNA analogue was also supported by the importance of gamma-aminoacid-containing compounds in natural products of biological activity and by the known stability of gamma-peptides to enzymatic degradation. Furthermore, our work could contribute to the study of the role of nucleopeptides as prebiotic material in a PNA world that could successively lead to the actual DNA/RNA/protein world, as recently assumed.


Assuntos
Aminobutiratos/química , Ácidos Nucleicos Peptídicos/química , Sequência de Bases , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Conformação Molecular , Estrutura Molecular , Sondas de Ácido Nucleico/síntese química , Sondas de Ácido Nucleico/química , Ácidos Nucleicos Peptídicos/síntese química , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta , Temperatura
7.
Biochim Biophys Acta ; 874(1): 76-81, 1986 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-3768378

RESUMO

Reaction in anaerobic conditions of bovine hemoglobin with bis(2,3-dibromosalycyl)fumarate resulted in new derivatives with P50 in excess of 40 mmHg, as determined at 37 degrees C in 0.15 M Cl- at pH 7.4. Although the chromatographic preparations indicated some heterogeneity of the reacted material, the proteins obtained were homogeneous with regard to sedimentation velocity, which showed the presence of only nondissociable tetrameric species. SDS gel electrophoresis showed the presence of a new band with a mobility corresponding approximately to a molecular mass of 32 kDa, indicating the presence of covalent intramolecular crosslinks between subunit pairs. Chromatographic analyses indicated that both alpha and beta chains were chemically modified. The retention times in rats of the crosslinked hemoglobin was 10-times longer than that of untreated hemoglobin.


Assuntos
Aspirina/análogos & derivados , Reagentes de Ligações Cruzadas/farmacologia , Hemoglobinas/metabolismo , Oxigênio/metabolismo , Animais , Aspirina/farmacologia , Bovinos , Eletroforese em Gel de Poliacrilamida , Hemoglobinas/análise , Concentração de Íons de Hidrogênio , Masculino , Conformação Proteica , Ratos , Ratos Endogâmicos
8.
Biochim Biophys Acta ; 1156(1): 50-6, 1992 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-1472538

RESUMO

UNLABELLED: The present experiments were done to determine plasma retention, urinary excretion, and acute renal effects of bolus administration (20 mg/100 g), of hemoglobins (human, bovine and porcine) whose tetrameric structure was stabilized by a pseudo-cross-link between the beta-chains. Standard renal clearance studies showed that these preparations had no immediate adverse effects on GFR or ERPF, however, urine flow and electrolyte excretion commonly increased. Plasma disappearance curves best fit a double-exponential and showed components with half-times of 28 +/- 3 and 257 +/- 43 min. A variable fraction, 57 +/- 6%, appeared in the urine, in phase with the early-fast component of plasma disappearance. This in vivo finding of extensive urinary excretion conflicted with sedimentation velocity analysis of these preparations which indicated a homogenous preparation with mean molecular weight of a stable and therefore, unfilterable tetramer. It appears that the glomerular filter selects for permeant species not easily detected by sedimentation velocity analysis. The different species may reflect the presence, within the PXLs of conformational-slow-equilibria among isomeric forms with different degrees of filterability. IN CONCLUSION: It is important, useful and simple to determine urinary excretion as a means to ascertain molecular stability in vivo.


Assuntos
Hemoglobinas/farmacocinética , Rim/metabolismo , Animais , Bovinos , Eletrólitos/urina , Hemoglobinas/administração & dosagem , Hemoglobinas/isolamento & purificação , Hemoglobinúria/urina , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Suínos
9.
J Mol Biol ; 202(2): 343-48, 1988 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-2845098

RESUMO

In the absence of Cl- in Hepes buffer at pH 7.4, the oxygen affinity of bovine and human hemoglobin is equally sensitive to 2,3-diphosphoglyceric acid. The low oxygen affinity measured for bovine hemoglobin at physiological salt concentration can be explained by the high affinity of Cl- anions for oxygen-linked sites that are absent in human hemoglobin. Bovine hemoglobin can discriminate between the different halogens in the sense that different halide concentrations are necessary to produce the same P50. Competition experiments indicate that the halogens interact with the same oxygen-linked sites. In agreement with the different affinities for halides, the Bohr effect of bovine hemoglobin is larger in the presence of Cl- than in that of Br- and there is good agreement between the number of protons and anions exchanged with the solvent upon oxygenation of bovine hemoglobin.


Assuntos
Hemoglobinas/metabolismo , Oxigênio/metabolismo , Animais , Bovinos , Ácidos Difosfoglicéricos/farmacologia , Hemoglobina A/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Oxiemoglobinas/metabolismo , Prótons
10.
J Leukoc Biol ; 67(2): 174-82, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10670577

RESUMO

The clearance of apoptotic cells is crucial to avoid chronic inflammation and autoimmunity. Little is known about the factors that regulate it in vivo. We show that granulocyte-macrophage colony-stimulating factor (GM-CSF) administration to carcinoma patients confers to their leukocytes a significantly higher ability to phagocytose apoptotic cells than before (P < 0.005). GM-CSF increased the concentration of monocytes and polymorphonuclear leukocytes in the peripheral blood and activated circulating polymorphonuclear leukocytes. Both effects abated early after treatment, whereas phagocytosis of apoptotic cells was still significantly higher after 18 days compared with basal values (P < 0.005 and P < 0.025 for monocytes and polymorphonuclear leukocytes, respectively). On in vitro phagocytosis of apoptotic cells monocytes, but not polymorphonuclear leukocytes, up-regulated MHC class II membrane expression. These findings are consistent with the possibility that GM-CSF endows both scavenger and antigen-presenting leukocytes with the ability to internalize apoptotic tumor cells.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma de Células Renais/patologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Fatores Imunológicos/farmacologia , Neoplasias Renais/patologia , Monócitos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Adulto , Idoso , Antineoplásicos/uso terapêutico , Carcinoma/sangue , Carcinoma/patologia , Carcinoma de Células Renais/sangue , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/terapia , Neoplasias do Colo/sangue , Neoplasias do Colo/patologia , Terapia Combinada , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Humanos , Fatores Imunológicos/uso terapêutico , Interferon-alfa/uso terapêutico , Células Jurkat , Neoplasias Renais/sangue , Contagem de Leucócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/patologia , Fagocitose/efeitos dos fármacos , Tretinoína/uso terapêutico
11.
FEBS Lett ; 466(1): 35-9, 2000 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-10648807

RESUMO

In 1965 Fruchter and Crestfield (J. Biol. Chem. 240, 2868-3874) observed that dimeric RNase A prepared by lyophilization from acetic acid could be separated into two forms. Surprisingly, no other structural or functional differences could be detected between the two forms. In 1998 a structure for dimeric RNase A was determined by X-ray crystallography by Liu et al. (Proc. Natl. Acad. Sci. USA 95, 3437-3442). We found that the two forms of dimeric RNase A have indeed different structural and functional properties, and suggest that the dimer whose structure was investigated by Liu and coworkers may be identified with the lesser form of dimeric RNase A.


Assuntos
Ribonuclease Pancreático/química , Animais , Catálise , Bovinos , Dicroísmo Circular , Reagentes de Ligações Cruzadas , Dimerização , Técnicas In Vitro , Masculino , Pâncreas/enzimologia , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , Ribonuclease Pancreático/isolamento & purificação , Ribonuclease Pancreático/metabolismo , Sêmen/enzimologia , Especificidade por Substrato , Sulfonas
12.
Neurology ; 57(6): 1126-8, 2001 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-11571352

RESUMO

To detect signs of axonal damage in MS, the authors investigated the occurrence in EMG of motor unit action potentials with satellite potentials (SP-MUAP) in the upper limb muscles in 10 consecutive patients with MS with cervical spinal cord demyelinating lesions and 10 control subjects. Subjects' SP-MUAP rate was 0 to 2.5% (median 0%) in the control group, and 0 to 17.5% (median 7.5%) in the MS group (p < 0.01). Motor unit remodeling secondary to axonal transection of spinal motor neurons traversing cervical demyelinating lesions may be hypothesized.


Assuntos
Axônios/fisiologia , Eletromiografia , Esclerose Múltipla/fisiopatologia , Adulto , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Neurônios Motores/fisiologia , Esclerose Múltipla/diagnóstico , Músculo Esquelético/inervação , Medula Espinal/fisiopatologia , Degeneração Walleriana/diagnóstico , Degeneração Walleriana/fisiopatologia
13.
Eur J Cancer ; 30A(9): 1292-8, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7999416

RESUMO

Starting from in vitro studies suggesting synergistic antitumour activity against renal cell cancer (RCC) of recombinant interleukin-2 (rIL-2) and alpha-interferon (IFN), a phase II trial was initiated to test the clinical activity of this combination. The two cytokines were administered sequentially, with the aim of reducing the risk of additive toxicity and enhancing the immunological reaction against the tumour. The original treatment schedule consisted of rIL-2 18 x 10(6) U/m2/day by continuous intravenous infusion for 120 h days 1-5, and alpha-IFN 2b, at a flat dose of 9 x 10(6) U by subcutaneous or intramuscular injection thrice in a week, from day 8 to 28. Treatment was planned to be continued for six or more 28-day cycles, depending on clinical response. 12 patients were treated according to this schedule; as some cardiovascular toxicity was experienced in this set of patients, 11 further patients were treated with half-dose rIL-2 (i.e. 9 x 10(6) U/m2/day). 17 out of 23 enrolled patients completed at least one cycle of treatment and were evaluated for response. We observed six major responses [one complete response (CR) + five partial responses (PR)] for an objective response rate of 35% [95% confidence interval (CI) 17-59%]. 5 additional patients achieved stabilisation of disease; one of them reached CR after surgical extirpation of a lung mass. Sites of response included lung, nodes and bone. Duration of response is 12+ months for CR; 17, 16, 12+, 9 and 9 months for PRs. Median survival is 16 months. Response was not significantly different between full-dose and half-dose rIL-2. Considering stable disease (SD) as responses, there seemed to be a higher chance of response for patients with smaller tumour burden (P = 0.032). The toxicity of rIL-2 treatment, mainly cardiovascular, was substantial; 9 patients experienced severe cardiotoxicity, consisting of major arrhythmias, myocardial ischaemia, reduction of ejection fraction measured with heart radionuclide scan, and were excluded from continuing treatment. Other rIL-2-related toxicities forcing exclusion from the study were severe thrombocytopenia (1 case), and generalised exfoliative dermatitis requiring steroids (1 case). Otherwise, treatment was well tolerated; rIL-2-related toxicities promptly recovered after rIL-2 discontinuation in the majority of cases, and no treatment-related deaths were reported. The half-dose rIL-2 regimen was significantly less toxic in terms of hypotension (P = 0.014), fever (P = 0.014), oliguria (P = 0.042), serum creatinine elevation (P = 0.009) and prothrombin time elongation (P = 0.038).(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Carcinoma de Células Renais/terapia , Interferon-alfa/administração & dosagem , Interleucina-2/administração & dosagem , Neoplasias Renais/terapia , Adulto , Idoso , Feminino , Coração/efeitos dos fármacos , Humanos , Interleucina-2/efeitos adversos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Indução de Remissão , Fatores de Tempo , Resultado do Tratamento
14.
Thromb Haemost ; 74(3): 868-73, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8571312

RESUMO

To improve the safety of plasma derived factor VIII (FVIII) concentrate, we introduced a final super heat treatment (100 degrees C for 30 min) as additional virus inactivation step applied to a lyophilized, highly purified FVIII concentrate (100 IU/mg of proteins) already virus inactivated using the solvent/detergent (S/D) method during the manufacturing process. The efficiency of the super heat treatment was demonstrated in inactivating two non-lipid enveloped viruses (Hepatitis A virus and Poliovirus 1). The loss of FVIII procoagulant activity during the super heat treatment was of about 15%, estimated both by clotting and chromogenic assays. No substantial changes were observed in physical, biochemical and immunological characteristics of the heat treated FVIII concentrate in comparison with those of the FVIII before heat treatment.


Assuntos
Fator VIII/isolamento & purificação , Hepatovirus/isolamento & purificação , Poliovirus/isolamento & purificação , Animais , Antígenos Virais/biossíntese , Modelos Animais de Doenças , Fator VIII/efeitos adversos , Fator VIII/imunologia , Feminino , Hepatovirus/imunologia , Temperatura Alta , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Poliovirus/imunologia , Coelhos
15.
Hum Pathol ; 29(11): 1189-94, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9824094

RESUMO

The prognostic role of the expression of bcl-1, bcl-2, bax, PCNA, and DNA-ploidy in a series of 25 oral squamous cell carcinoma (SCC) was investigated. The average age of the patients was 62.04 years (range, 27 to 81 years), with a sex ratio (M/F) of 23:2. The follow-up mean time was 2.24 years (range, 8 months to 8 years from surgery). Immunohistochemistry for PCNA, bcl-2, bcl-1, and bax proteins was carried out on 5-microm serial sections from formalin-fixed, paraffin-embedded tissue. The findings were compared with clinicopathologic data and with follow-up. The statistical evaluation of the results of the current study suggests that the low positivity for PCNA with a high positivity for bcl-2 protein are related to a better clinical behavior of the tumors. By converse, a high expression of PCNA, bax, and bcl-1 appears to correlate with a worse prognosis. All of our cases of SCC showed the presence of aneuploid populations, which was not correlated with the clinicopathologic parameters or with the overexpression of bcl-1, bcl-2, bax, and PCNA. Therefore, the aneuploidy per se did not predict the clinical evolution for the single cases of cancers. Nevertheless, once the parameters considered for the evaluation of DNA were examined in detail, it appeared that some of them, individually or combined with each other or with the expression of bcl-1, bcl-2, and bax, gained statistical significance in predicting the clinical evolution of SCC of our series. Particularly, high values of 2cDI and DNA-MG and the absence or reduction of the euploid population were associated with a short interval between surgery and recurrence or death, and this significance persisted when the simultaneous presence of overexpression of bcl-1 was considered.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Ciclina D1/biossíntese , DNA de Neoplasias/análise , Neoplasias Bucais/metabolismo , Proteínas de Neoplasias/biossíntese , Antígeno Nuclear de Célula em Proliferação/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia , Ploidias , Prognóstico , Análise de Sobrevida , Proteína X Associada a bcl-2
16.
J Dent Res ; 78(7): 1345-53, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10403462

RESUMO

Odontogenic keratocysts are occasionally (4-5%) associated with the nevoid basal cell carcinoma syndrome, a pleiotropic, autosomal disorder presenting a spectrum of developmental abnormalities and a predisposition for the development of different neoplasms. The aim of this study was to establish whether keratocysts showing clinically aggressive behavior associated with nevoid basal cell carcinoma syndrome reflect differences in cellular proliferation rate and/or in the expression of oncoproteins and tumor suppressor genes. For this reason, formalin-fixed paraffin-embedded sections of odontogenic keratocysts associated with the nevoid basal cell carcinoma syndrome (16 cases) and sporadic odontogenic keratocysts (16 cases) were compared for expression of proliferating cell nuclear antigen (PCNA) and p53, bcl-2, and bcl-1 (cyclin D1) onco-proteins. Most of the epithelial lining of odontogenic keratocysts associated with the nevoid basal cell carcinoma syndrome showed nuclear immunopositivity for p53 protein and overexpression of cyclin D1 with various degrees of staining intensity. All sporadic odontogenic keratocysts were negative for p53 and cyclin D1. The expressions of bcl-2 oncoprotein were found to be substantially similar between the two groups of lesions, with a cytoplasmic immunopositivity localized only in the resting reserve basal layer of the epithelium. PCNA expression showed no statistically significant difference between the two groups of lesions. In conclusion, the finding of cyclin D1 and p53 overexpression in odontogenic keratocysts associated with the nevoid basal cell carcinoma syndrome could be considered a hallmark of a mutated cellular phenotype, thus leading to the hypothesis that their aggressive clinical behavior could be due to a dysregulation of the expression of cyclin D1 and p53 proteins, involved in a check-point control of cellular proliferation.


Assuntos
Apoptose/genética , Síndrome do Nevo Basocelular/patologia , Cistos Odontogênicos/patologia , Proteínas Oncogênicas/genética , Análise de Variância , Síndrome do Nevo Basocelular/genética , Ciclo Celular/genética , Divisão Celular/genética , Núcleo Celular/ultraestrutura , Ciclina D1/análise , Ciclina D1/genética , Citoplasma/ultraestrutura , Células Epiteliais/patologia , Epitélio/patologia , Feminino , Regulação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor/genética , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Masculino , Mutação/genética , Cistos Odontogênicos/genética , Fenótipo , Antígeno Nuclear de Célula em Proliferação/análise , Antígeno Nuclear de Célula em Proliferação/genética , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/genética
17.
Biophys Chem ; 24(1): 47-52, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3741988

RESUMO

This paper shows that analysis of sedimentation equilibrium data, searching for average molecular weights, gives quantities which are dependent on the total protein concentration of the samples, while knowledge of the molecular weight of the monomeric subunits allows a more meaningful search for the concentrations of the individual polymeric components of the system. From these the various average molecular weights can be construed, and the various dissociation equilibrium constants evaluated. Also, in this paper considerations are proposed on the meaning of nonideality terms in associating systems and possible ways for estimating them. As an example the proposed procedures have been applied to measurements of sedimentation equilibrium in carbonmonoxyhemoglobin.


Assuntos
Hemoglobinas , Substâncias Macromoleculares , Proteínas , Hemoglobinas/isolamento & purificação , Humanos , Matemática , Peso Molecular
18.
Biophys Chem ; 16(2): 159-63, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7139049

RESUMO

The rate of reaction of the terminal valines of the alpha- and beta-chains of hemoglobin with 1-fluoro-2,4-dinitrobenzene was followed spectrophotometrically at 353 nm. The variation with pH of the rate of dinitrophenylation of these groups was measured for both carbonmonoxy- and deoxyhemoglobin. In carbonmonoxyhemoglobin the results indicated a pK near 6.7 and 7.7 for the amino terminal groups of the two kinds of subunits, and were attributed to the alpha- and beta-chains respectively. Removal of ligands produced an increase of 0.1 in both pK values and a decrease of 40% of the pH-independent kinetic constant for dinitrophenylation of the beta-subunits. These modifications are due to the conformational changes associated with ligand binding in the system. In phosphate buffers the contribution to the Bohr effect of the amino terminal residues of either chains is negligible.


Assuntos
Carboxihemoglobina/metabolismo , Dinitrofluorbenzeno/farmacologia , Hemoglobinas/metabolismo , Nitrobenzenos/farmacologia , Valina , Adulto , Humanos , Concentração de Íons de Hidrogênio , Cinética , Ligação Proteica , Espectrofotometria
19.
Biophys Chem ; 48(1): 31-8, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8257765

RESUMO

Recent developments of ultrafast fluorimeters allow measuring time-resolved fluorescence on the picosecond time scale. This implies one is able to monitor lifetimes and anisotropy decays of highly quenched systems and of systems that contain fluorophores having lifetimes in the subnanosecond range; both systems that emit weak signals. The combination of weak signals and very short lifetimes makes the measurements prone to distortions which are negligible in standard fluorescence experiments. To cope with these difficulties, we have designed a new optical cell for front-face optics which offers to the excitation beam a horizontal free liquid surface in the absence of interactions with optical windows. The new cell has been tested with probes of known lifetimes and anisotropies. It proved very useful in detecting tryptophan fluorescence in hemoglobin. If only diluted samples are available, which cannot be used in front-face optics, regular square geometry can still be utilized by inserting light absorbers into a cuvette of 1 cm path length.


Assuntos
Técnicas de Química Analítica/instrumentação , Técnicas de Química Analítica/métodos , Polarização de Fluorescência , Óptica e Fotônica/instrumentação , Oxiemoglobinas/química , Espalhamento de Radiação , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos , Análise Espectral Raman , Fatores de Tempo , Triptofano/química
20.
Biophys Chem ; 28(3): 215-23, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3440122

RESUMO

This paper presents data on the effect of phosphates and polyphosphates on the formation of hemoglobin S fiber, and on the Bohr effect of hemoglobin S samples whose concentration was high enough (near 5 mM) in order to form fibers upon deoxygenation. The experiments were performed in 0.2 M Bistris or Tris buffers at 30 degrees C in the presence and absence of inositol hexakisphosphate and of 2,3-diphosphoglycerate. Alternatively, 0.2 M phosphate buffers were used without addition of effectors. Under these conditions, few fibers were formed in Tris or Bistris buffers, while extensive fiber formation occurred in the presence of phosphates and polyphosphates. In all cases, increasing pH strongly inhibited fiber formation. At pH 7.5 and above, fibers were not formed in our samples. In the presence of phosphates and polyphosphates fiber formation reduced the oxygen affinity of hemoglobin S with respect to either hemoglobin A or soluble hemoglobin S under similar experimental conditions. The fiber-polyphosphate complexes showed a larger Bohr effect than that in hemoglobin A. In the presence of inositol hexakisphosphate fiber-forming solutions of hemoglobin S liberated as much as six protons per tetramer upon oxygen binding. The increased liberation of protons was probably due to a higher affinity of the effectors for the fibers of hemoglobin S. Very likely the higher affinity was supported by a conformational change of hemoglobin S specific for the fibers.


Assuntos
Hemoglobina Falciforme/metabolismo , Oxiemoglobinas/metabolismo , Fosfatos/farmacologia , Ácido Fítico/farmacologia , Soluções Tampão , Hemoglobina A/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Cinética
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