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1.
Eur Arch Otorhinolaryngol ; 277(4): 1031-1038, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31993767

RESUMO

PURPOSE: Our aim was to determine whether perioperatively administered corticosteroid treatment has any beneficial effect on the outcome of stapes surgery, with special regard to the audiological results and early postoperative morbidity. METHODS: 84 CO2 laser stapedotomies performed in our institute between 2013 and 2018 were included in our investigation. All cases underwent preoperative and mid-term postoperative pure-tone audiometric evaluation. Vestibular complications were also evaluated. The cases were subdivided into two groups, 23 patients received perioperative i.v. methylprednisolone treatment ("S") while the other 61 patients ("nS") did not receive any adjuvant pharmacological therapy. The data were analyzed retrospectively using IBM SPSS Statistics. RESULTS: CO2 laser stapedotomy proved to be a successful intervention with a significant improvement in ABG and AC thresholds as well. Long-term BC levels were significantly better compared to preoperative ones in the S group; however, in the nS group, no difference could be shown. Hearing and ABG gain were significantly superior in group S [28.1 dB (SD11.2) vs. 18.1 dB (SD 10.9) and 23.9 dB(SD 9.8) vs. 17.2 dB (SD 9.5), respectively]. CONCLUSION: No significant inner ear damage was detectable in the results of our CO2 laser stapedotomy method; however, the positive effect of corticosteroid treatment could be demonstrated through the postoperative hearing levels. We found no statistical difference in early postoperative morbidity. According to our data, the routine administration of corticosteroids during stapes surgery could be an issue worthy of consideration. The effects of perioperative treatment vs that on the first day after surgery, and topical vs. systemic treatment could be the subject of further investigation in a prospective manner.


Assuntos
Glucocorticoides/administração & dosagem , Perda Auditiva/cirurgia , Terapia a Laser , Metilprednisolona/administração & dosagem , Otosclerose , Cirurgia do Estribo , Adulto , Audiometria de Tons Puros , Feminino , Perda Auditiva/diagnóstico , Perda Auditiva/tratamento farmacológico , Humanos , Infusões Intravenosas , Lasers de Gás/uso terapêutico , Masculino , Pessoa de Meia-Idade , Otosclerose/diagnóstico , Otosclerose/tratamento farmacológico , Otosclerose/cirurgia , Assistência Perioperatória , Estudos Retrospectivos , Resultado do Tratamento
2.
Sci Rep ; 4: 6308, 2014 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-25200937

RESUMO

We study ensemble-based graph-theoretical methods aiming to approximate the size of the minimum dominating set (MDS) in scale-free networks. We analyze both analytical upper bounds of dominating sets and numerical realizations for applications. We propose two novel probabilistic dominating set selection strategies that are applicable to heterogeneous networks. One of them obtains the smallest probabilistic dominating set and also outperforms the deterministic degree-ranked method. We show that a degree-dependent probabilistic selection method becomes optimal in its deterministic limit. In addition, we also find the precise limit where selecting high-degree nodes exclusively becomes inefficient for network domination. We validate our results on several real-world networks, and provide highly accurate analytical estimates for our methods.

3.
J Perinatol ; 33(11): 851-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23765172

RESUMO

OBJECTIVE: To assess how a standard practice for nutrition support in very low birth weight (VLBW) neonates would impact on their hospital course. STUDY DESIGN: This was a prospective, single center, before vs after comparison of a non-standardized approach to nutrition in VLBW neonates to a standardized approach. Standardization of feeding initiation, feeding volume and caloric advancement, management of feeding aspirates (residuals), use of starter parenteral nutrition (PN), use of breast milk and donor breast milk, initiation and discontinuation of intravenous (IV) intralipids, documentation of protein use, and utilization of percutaneously inserted central venous catheters were performed. Multiple outcome measures were evaluated. Fisher's exact, Mann-Whitney U-tests and χ(2) tests were used for statistical analysis. RESULT: Sixty-nine infants in the pre-standardization (non-standardized) group were compared with 154 infants in the standardized approach group. Analysis was performed for each group as a whole. Statistically significant improvements were seen in multiple areas for the standardized group including the day of life birth weight was regained (P<0.0005), use of breast milk as the initial feeding (P<0.0001), use of starter PN on admission (P<0.0001), earlier time for initiation of PN (P<0.0001), decreased use of PN overall (P<0.0001), enteral protein use (P<0.0001), earlier time for initiation of IV intralipids (P<0.002), day of life for full enteral feeds (P<0.0005) and first day for initiation of enteral feeds (P<0.0001). Fewer infants born microcephalic at birth remained so at discharge in the standardized group as compared with the pre-standardized group (P<0.02). Similarly, less infants born small for gestational age at birth remained so at discharge in the standardized group as compared with the pre-standardized group (P<0.05). Two cases of necrotizing enterocolitis (NEC) occurred in the pre-standardization group and one in the standardized group. No coagulase-negative Staphlococcal infections or line infections occurred during the entire study period. Two cases of sepsis occurred in the pre-standardization group, both in infants <750 g. No cases of sepsis occurred in the standardized group. Cost savings were remarkable from decreased PN usage in the standard group. CONCLUSION: Implementation of a standardized approach to nutrition in VLBW infants reduces the use of PN thereby reducing cost, causes a more rapid regain of birth weight, decreases the number of babies that are small for gestational age and microcephalic at discharge, and decreases the time to full enteral feeds. No adverse increases in mortality, sepsis, NEC, coagulase-negative Staphlococcal infections or line infections occurred.


Assuntos
Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido de muito Baixo Peso , Cateterismo Venoso Central , Ingestão de Energia , Feminino , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Masculino , Leite Humano , Nutrição Parenteral , Estudos Prospectivos , Resultado do Tratamento , Aumento de Peso
4.
Microsc Microanal ; 18(2): 406-20, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22436336

RESUMO

In this series of articles, a method is presented that performs (semi)quantitative phase analysis for nanocrystalline transmission electron microscope samples from selected area electron diffraction (SAED) patterns. Volume fractions and degree of fiber texture are determined for the nanocrystalline components. The effect of the amorphous component is minimized by empirical background interpolation. First, the two-dimensional SAED pattern is converted into a one-dimensional distribution similar to X-ray diffraction. Volume fractions of the nanocrystalline components are determined by fitting the spectral components, calculated for the previously identified phases with a priori known structures. These Markers are calculated not only for kinematic conditions, but the Blackwell correction is also applied to take into account dynamic effects for medium thicknesses. Peak shapes and experimental parameters (camera length, etc.) are refined during the fitting iterations. Parameter space is explored with the help of the Downhill-SIMPLEX. The method is implemented in a computer program that runs under the Windows operating system. Part I presented the principles, while part II elaborated current implementation. The present part III demonstrates the usage and efficiency of the computer program by numerous examples. The suggested experimental protocol should be of benefit in experiments aimed at phase analysis using electron diffraction methods.

5.
Discrete Math ; 311(13): 1197-1203, 2011 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-21643469

RESUMO

Various topological indices have been put forward in different studies from bio-chemistry to pure mathematics. Among them the Wiener index, the number of subtrees and the Randic index have received great attention from mathematicians. While studying the extremal problems regarding these indices among trees, one interesting phenomenon is that they share the same extremal tree structures. Much effort was devoted to the study of the correlations between these various indices. In this note we provide a common characteristic (the 'semi-regular' property) of these extremal structures with respect to the above mentioned indices, among trees with a given maximum degree. This observation leads to a more unified approach for characterizing these extremal structures. As an application/example, we illustrate the idea by studying the extremal trees regarding the sum of distances between all pairs of leaves of a tree, a new index, which recently appeared in phylogenetic tree reconstruction and the study of the neighborhood of trees.

6.
Exp Oncol ; 30(4): 327-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19112433

RESUMO

Crystal violet treatment of formalin fixed paraffin embedded tissue slides greatly reduces the endogenous autofluorescence, and allows immunofluorescence (IF) staining with FITC or Alexa488 conjugated antibodies. Using cold CCD camera to capture the fluorescence images makes this staining method very sensitive. Here we show that combination of IF with the simultaneous recording of crystal violet induced red and Hoechst 33258 induced blue fluorescence permits the localization of the IF signal over a cytoplasmic: nuclear red:blue stain that visualizes the microscopic anatomy of the underlying tissue. To make the visual interpretation of the IF staining easier for microscopists, who are used to DAB staining over weak hematoxilin-eosin background, we created a simple color conversion procedure that turns the captured three-color fluorescence RGB (red, green, blue) images over a black background into four color CMYK (cyan, magenta, yellow, key color (black)) images.


Assuntos
Imunofluorescência/métodos , Microscopia de Fluorescência/métodos , Inclusão em Parafina , Coloração e Rotulagem/métodos , Benzoxazinas , Endométrio/patologia , Feminino , Humanos , Microscopia de Fluorescência/instrumentação , Oxazinas
7.
Oncogene ; 26(7): 982-92, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-16909106

RESUMO

We have previously identified PRIMA-1, a low molecular weight compound that restores the transcriptional transactivation function to mutant p53 and induction of apoptosis. To explore the molecular mechanism for PRIMA-1-induced mutant p53-dependent apoptosis, we examined the intracellular distribution of mutant p53 upon treatment with PRIMA-1(MET) by immunofluorescence staining. We found that PRIMA-1(MET) induced nucleolar translocation of mutant p53 and the promyelocytic leukemia (PML) nuclear body-associated proteins PML, CBP and Hsp70. Levels of Hsp70 were significantly enhanced by PRIMA-1(MET) treatment. PRIMA-Dead, a compound structurally related to PRIMA-1 but unable to induce mutant p53-dependent apoptosis, failed to induce nucleolar translocation of mutant p53. Our results suggest that redistribution of mutant p53 to nucleoli plays a role in PRIMA-1-induced apoptosis.


Assuntos
Compostos Aza/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Nucléolo Celular/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Transporte Ativo do Núcleo Celular , Apoptose/genética , Linhagem Celular Tumoral , Nucléolo Celular/genética , Metilação de DNA , Humanos , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Proteína da Leucemia Promielocítica , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética
8.
Virology ; 288(2): 275-82, 2001 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-11601899

RESUMO

We have studied the expression and the localization of the cellular proteins CBP/p300 and RBP-Jk in in vitro EBV-infected human B lymphocytes in relation to the EBNA-2 and EBNA-5 proteins. We found that the level of CBP/p300 was elevated drastically by EBV infection and also after activation by CD40 ligation. Thus the increase in CBP/p300 expression in the EBV-infected cells is related to the virus-induced activation and proliferation of the cells. EBNA-2 and RBP-Jk colocalized in the nucleoplasm, which is in accordance with their functional interaction. We confirmed earlier reports about the presence and colocalization of EBNA-5 and CBP in the nuclear POD bodies. On the other hand, neither EBNA-2 nor p300 was detected in the PODs. The expression of these two proteins overlapped in some distinct dots of the nucleoplasm. Taken together, the different patterns of CBP and p300 expression and their different localization in relation to the PML bodies and two EBV-encoded proteins in the B cells may provide some clue to their distinct functional roles.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Proteínas Nucleares/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Linfócitos B/metabolismo , Linfócitos B/virologia , Proteína de Ligação a CREB , Linhagem Celular , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/biossíntese , Antígenos Nucleares do Vírus Epstein-Barr/biossíntese , Antígenos Nucleares do Vírus Epstein-Barr/genética , Expressão Gênica , Herpesvirus Humano 4/genética , Humanos , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina , Proteínas Nucleares/biossíntese , Tonsila Palatina/citologia , Transativadores/biossíntese , Fatores de Transcrição/biossíntese , Transcrição Gênica , Transfecção , Proteínas Virais
9.
Int J Cancer ; 93(5): 714-9, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11477584

RESUMO

Latent Epstein-Barr virus (EBV) uses two alternative strategies to express the Epstein-Barr nuclear antigens (EBNAs). Resting normal B cells harboring latent virus and Burkitt's lymphoma (BL) cells use monocistronic messages generated from the Q promoter (restricted strategy). EBV-transformed immunoblasts express all EBNAs by using giant messages generated from the W/C promoter (full program). Whether the virus establishes the restricted program on primary infection of a BL cell (or its progenitor) or, alternatively, whether such cells are generated by phenotypic down-regulation from the immunoblast is unclear. We found previously that conversion of EBV-negative BL lines to EBV-positive sublines required repeated exposure to large virus doses. The converted sublines used the full program. However, the possibility that cells with a full program had a selective advantage during the long period of in vitro passage could not be excluded. We therefore infected EBV-negative BL lines with recombinant EBV carrying a neomycin resistance marker. Most convertants of the 12 lines tested were positive for YUK splicing, indicative of the full program, but some were also positive for the restricted QUK splice program. One convertant DG75 line showing both YUK and QUK was cloned and gave rise to stable QUK users. We conclude that EBV infection of established BL lines can give rise to subclones with either the full or the restricted program. The fact that all EBVs carrying BL lines use the restricted program in vitro may be a consequence of immunoselection.


Assuntos
Linfoma de Burkitt/patologia , Transformação Celular Viral/genética , Antígenos Nucleares do Vírus Epstein-Barr/genética , Regulação Neoplásica da Expressão Gênica , Herpesvirus Humano 4/fisiologia , Regiões Promotoras Genéticas/fisiologia , Antibacterianos/farmacologia , Linfoma de Burkitt/genética , Linhagem Celular Transformada , Resistência Microbiana a Medicamentos , Antígenos Nucleares do Vírus Epstein-Barr/análise , Citometria de Fluxo , Herpesvirus Humano 4/efeitos dos fármacos , Humanos , Neomicina/farmacologia , Células Tumorais Cultivadas , Proteínas da Matriz Viral/análise , Proteínas Virais
10.
Clin Pediatr (Phila) ; 40(1): 27-33, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11210083

RESUMO

This paper acquaints pediatricians and health care personnel with the triad of poor weight gain, frequent breastfeeding, and food refusal in infants during the second 6 months of life. The histories of six infants aged 8-11 months, with failure to thrive, food refusal, and frequent breastfeeding, are presented. All the mothers were facing significant stresses, which may have decreased their breast milk supply, and were leading them to use breastfeeding for their comfort and/or the comfort of their infant. The infants responded with continued frequent breastfeeding, refusal of complementary foods, and decreased weight gain. These infants fit the characteristics of the vulerable child syndrome. Treatment of these infants required evaluation and treatment of the mothers' psychosocial issues along with a behavioral feeding program. Even with this multidisciplinary approach, these infants showed very slow catch-up growth. Pediatricians and health care personnel should use and build on this information in the evaluation and treatment of infants with similar problems.


Assuntos
Aleitamento Materno , Alimentos Infantis , Aleitamento Materno/psicologia , Insuficiência de Crescimento , Feminino , Humanos , Lactente , Lactação/fisiologia , Masculino , Relações Mãe-Filho
11.
Proc Natl Acad Sci U S A ; 98(3): 1012-7, 2001 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-11158586

RESUMO

Several recent findings have indicated that the promyelocytic leukemia gene product (PML) oncogenic domains (PODs) are involved in proteasome-mediated degradation of ubiquitinated proteins. We wanted to examine the intracellular distribution of PML protein in the presence of a proteasome inhibitor. We used high-resolution microscopy to study the distribution of PML protein and other POD-associated proteins along with the proteasomes themselves under normal conditions and in cells treated with the proteasome inhibitor, MG132. Inhibition of the proteasomes in MCF-7, HeLa, and IB-4 cell lines resulted in a radical redistribution of the POD-associated proteins PML, Sp100, and SUMO-1. After 6-10 h of MG132 treatment, PML, Sp100, and SUMO-1 were no longer detectable in the PODs and accumulated mainly in the nucleolus. Moreover, MG132 treatment changed the cellular distribution of the proteasomes. Interestingly, this included the accumulation in euchromatin areas of the nucleus and within the nucleoli. Several non-POD-associated proteins did not change their cellular distribution under the same conditions. The accumulation of POD-associated proteins and proteasomes in the nucleoli of MG132-treated cells indicates that these proteins may target the nucleoli under normal conditions and that the nucleolus may have a function in the regulation of proteasomal protein degradation.


Assuntos
Nucléolo Celular/metabolismo , Núcleo Celular/metabolismo , Cisteína Endopeptidases/metabolismo , Complexos Multienzimáticos/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Neoplasias da Mama , Nucléolo Celular/ultraestrutura , Núcleo Celular/ultraestrutura , Feminino , Células HeLa , Humanos , Leucemia Promielocítica Aguda/genética , Proteína da Leucemia Promielocítica , Complexo de Endopeptidases do Proteassoma , Transporte Proteico , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor , Ubiquitinas/metabolismo
12.
Br J Cancer ; 84(1): 122-5, 2001 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-11139326

RESUMO

Presence of the Human Herpesvirus 8 (HHV8) genome has been reported in the bone marrow of multiple myeloma (MM) patients. So far, serological studies of HHV8 and MM have been inconsistent but have not included prospective epidemiological studies. We evaluated whether HHV8 infection is associated with increased risk for MM in a prospective population-based study of 39 000 Finnish subjects who donated serum samples in the period 1968-72. Serum samples from 47 subjects who developed MM during a 23-year follow-up and 224 age, area of residence and sex-matched subjects who remained healthy over a similar follow-up period were evaluated for HHV8 antibodies at enrollment, as assayed both with an immunofluorescence assay (IFA) for lytic and latent HHV8 antigens and by Western blot (WB) with three recombinant HHV8 proteins (ORFs 65, 73 and K8.1A). HHV8 seropositivity for at least one HHV8 protein on WB was found in 7% of the Finnish population and was not associated with the risk of developing MM (Relative Risk (RR) = 0.89, Confidence Interval (CI): 0.25-3.25). HHV8 seropositivity for lytic and latent antigens in the IFA was found in 16% and 0.4% of the Finnish population and tended to associate with risk of MM (RR = 2.02, CI: 0.94-4.33 and RR = 10.00, CI: 0.91-110.29, respectively). In conclusion, no statistically significant evidence for an association between HHV8 infection and the risk of future MM was found.


Assuntos
Infecções por Herpesviridae/complicações , Herpesvirus Humano 8/imunologia , Mieloma Múltiplo/virologia , Antígenos Virais/análise , Western Blotting , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Imunofluorescência , Infecções por Herpesviridae/imunologia , Humanos , Masculino , Mieloma Múltiplo/imunologia , Proteínas Nucleares/análise , Razão de Chances , Estudos Prospectivos , Risco , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Suécia , Proteínas Virais/análise
13.
J Hum Virol ; 4(5): 227-37, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11907380

RESUMO

OBJECTIVES: To understand the mechanism for the refractoriness of B-chronic lymphocytic leukemia (B-CLL) cells for Epstein-Barr virus (EBV)-induced immortalization. STUDY DESIGN/METHODS: Cultures were initiated with EBV-infected tonsillar B and B-CLL cells. Expression of EBNA-2 and some of the key players regulating G1/S phase transition such as c-myc expression, phosphorylation of Rb protein, expression of G1 cyclins, and the cyclin-dependent kinase inhibitor p27 were followed. RESULTS: In line with earlier studies, EBV infection induced c-myc expression, pRb phosphorylation, D2 and D3 expression, and disappearance of p27 in normal B cells. In contrast, EBV-infected B-CLL cells remained resting and they did not express c-myc; cyclin D2, ppRb and cyclin D3 were seen only in occasional cells. Importantly, p27 expression was maintained. CONCLUSIONS: In B-CLL cells, the expression of the EBV-encoded nuclear proteins EBNAs is not followed by entrance to the cell cycle. Thus, the difference in the interaction of EBV-normal B cells and EBV-B-CLL cells is already apparent early after infection.


Assuntos
Linfócitos B/metabolismo , Proteínas de Ciclo Celular/biossíntese , Herpesvirus Humano 4/metabolismo , Leucemia Linfocítica Crônica de Células B/metabolismo , Animais , Linfócitos B/citologia , Células Cultivadas , Ciclina D2 , Ciclina D3 , Inibidor de Quinase Dependente de Ciclina p27 , Ciclinas/biossíntese , Antígenos Nucleares do Vírus Epstein-Barr/biossíntese , Herpesvirus Humano 4/fisiologia , Humanos , Leucemia Linfocítica Crônica de Células B/sangue , Fosforilação , Proteínas Proto-Oncogênicas c-myc/biossíntese , Proteína do Retinoblastoma/metabolismo , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor/biossíntese , Proteínas Virais
14.
Int J Cancer ; 88(3): 439-47, 2000 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11054674

RESUMO

The gene defect responsible for the X-linked lymphoproliferative disease (XLP) is associated with an impaired control of Epstein-Barr virus (EBV) infection. The gene has been recently identified and the encoded protein (designated SH2D1A, DSHP or SAP) was characterized. It is a 128 amino acid (aa) protein, containing a single Src homology 2 (SH2) domain. It interacts with signaling lymphocytic activation molecule (SLAM) expressed on the surface of activated T and B cells. We show that activated T, but not activated B, cells express the SH2D1A protein. NK cells express the protein as well. Tumor lines originating from B, T or NK cells exhibited similar SH2D1A protein expression as the corresponding normal cells, with some notable exceptions. EBV-carrying, tumor phenotype representative (type I), but not EBV-carrying lymphoblastoid cell line (LCL)-like (type III) or EBV-negative Burkitt lymphoma (BL) lines expressed SH2D1A. The phenotypic switch from type I to type III in the EBV-carrying BL line Mutu was associated with a down-regulation of SH2D1A and up-regulation of SLAM. In contrast to normal ex vivo and long-term activated NK cells, 2 of 3 NK leukemia lines expressed SLAM. All 3 lines expressed SH2D1A, like their normal counterparts.


Assuntos
Proteínas de Transporte/análise , Glicoproteínas/análise , Imunoglobulinas/análise , Peptídeos e Proteínas de Sinalização Intracelular , Leucemia/metabolismo , Linfócitos/química , Sequência de Aminoácidos , Antígenos CD , Proteínas de Transporte/sangue , Linhagem Celular , Glicoproteínas/sangue , Humanos , Imunoglobulinas/sangue , Células Matadoras Naturais/química , Dados de Sequência Molecular , Receptores de Superfície Celular , Proteína Associada à Molécula de Sinalização da Ativação Linfocitária , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária
15.
Pediatr Cardiol ; 21(3): 228-33, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10818180

RESUMO

Adrenomedullin (ADM) is a vasoactive peptide with potent dilatory effects. We studied whether perioperative myocardial injury could be altered by the presence of ADM. Blood samples from 19 children with congenital heart disease undergoing surgical repair were collected at six time points: preoperative, on cardiopulmonary bypass (CPB), and 0, 3, 6, and 12 hours after CPB. Blood levels of ADM (pg/ml) and troponin-I (Tn-I; ng/ml), a specific marker of myocardial injury, were measured. Patients were divided into three groups based on their 12-hour Tn-I levels (I, < 10, n = 6; II, 10-25, n = 6; III, >25, n = 7). Preoperative Tn-I levels were within the normal range for all patients. Preoperative ADM levels in group I (with little or no evidence of myocardial injury) were significantly greater than those of either group II or III (242.7 +/- 15.4 vs 83.8 +/- 18 and 85.2 +/- 5.5, respectively; p < or = 0.0001 for each). The 12-hour ADM levels in group I remained significantly lower than preoperative levels (242.7 +/- 15.4 vs 197.4 +/- 11.6, p < or = 0.03) but higher than in the other groups. In group III, ADM increased at the 12-hour time point (159.2 +/- 6.5, p < or = 0.0001 vs baseline). Higher preoperative ADM levels are associated with lower levels of myocardial injury (as assessed by troponin-I release) during congenital heart surgery.


Assuntos
Ponte Cardiopulmonar , Cardiopatias Congênitas/sangue , Cardiopatias Congênitas/cirurgia , Traumatismo por Reperfusão Miocárdica/sangue , Peptídeos/sangue , Adrenomedulina , Criança , Pré-Escolar , Feminino , Humanos , Hipotermia Induzida , Lactente , Masculino , Troponina I/sangue
16.
Oncogene ; 19(14): 1801-6, 2000 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-10777214

RESUMO

EBNA-3 (also called EBNA-3A) is one of the EBV encoded nuclear antigens that are necessary for B-cell transformation. EBNA-3 is known to target RBPs, nuclear proteins that also interacts with EBNA-2, EBNA-4 and EBNA-6. In order to identify additional EBNA-3 targets, an EBV-transformed human lymphocyte cDNA library was screened in the yeast two-hybrid system with N-terminus truncated EBNA-3 that cannot interact with RBP-Jkappa. A clone, encoding Xap-2 protein, a cellular partner of Hepatitis B virus X-antigen was isolated. This protein is also known as the p38 subunit of the aryl hydrocarbon receptor complex (ARA9). The specific binding to EBNA-3 was confirmed by showing that the GST-Xap-2 precipitated EBNA-3 from CV1 cells that were infected with recombinant vaccinia virus expressing EBNA-3. Deletion of the C-terminus of Xap-2 eliminated the binding. Fusion with green fluorescent protein showed that Xap-2 is preferentially cytoplasmic but translocates to the nucleus upon expression of EBNA-3.


Assuntos
Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Antígenos da Hepatite B/metabolismo , Herpesvirus Humano 4/metabolismo , Proteínas/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Transativadores/metabolismo , Células 3T3 , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular , Linhagem Celular Transformada , DNA Complementar , Antígenos Nucleares do Vírus Epstein-Barr/genética , Herpesvirus Humano 4/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Dados de Sequência Molecular , Proteínas/genética , Receptores de Hidrocarboneto Arílico/genética , Proteínas Recombinantes de Fusão/genética , Frações Subcelulares , Técnicas do Sistema de Duplo-Híbrido , Proteínas Virais Reguladoras e Acessórias
17.
J Toxicol Clin Toxicol ; 37(4): 475-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10465244

RESUMO

INTRODUCTION: Verapamil is a papaverine-derived calcium channel blocker widely used for the treatment of hypertension and supraventricular tachyarrhythmias. It is one of the leading agents involved in pharmaceutical poisoning-related deaths among adults. CASE REPORT: We report a case of severe sustained-release verapamil poisoning associated with respiratory failure in an adult man who survived after receiving 4 days of partial liquid ventilation as a part of his medical management.


Assuntos
Bloqueadores dos Canais de Cálcio/intoxicação , Preparações de Ação Retardada/efeitos adversos , Insuficiência Respiratória/induzido quimicamente , Ventilação/métodos , Verapamil/intoxicação , Adulto , Resistência das Vias Respiratórias/efeitos dos fármacos , Humanos , Técnicas In Vitro , Masculino , Oxigênio/sangue , Radiografia , Síndrome do Desconforto Respiratório/induzido quimicamente , Insuficiência Respiratória/terapia , Tentativa de Suicídio
18.
Int J Cancer ; 81(4): 543-50, 1999 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-10225442

RESUMO

The D-type cyclins, involved in the regulation of G1 progression of the cell cycle, are expressed in a lineage-specific manner. Normal hematopoietic cells express cyclin D2 and/or D3. In order to determine whether their expression pattern changes in lymphoid tumors, we examined cyclin D2 and D3 expression in non-neoplastic and neoplastic lymphoid lesions, using a sensitive immunohistochemical amplification method. Centroblasts in lymphoid follicles of reactive lymph nodes expressed exclusively cyclin D3 and no D2. Interfollicular areas contained scattered cyclin D3 and D2 positive cells. By double staining, cyclin D3 was detected in CD79a positive B cells, CD3 positive T cells and CD68 positive macrophages. Cyclin D2 was present only in CD3 positive T cells. Neoplastic lymphoid lesions included 33 B cell lymphomas, 9 T cell lymphomas and 12 Hodgkin's lymphomas. The B cell lymphomas comprised 9 follicular lymphomas (FL), 1 Burkitt lymphoma (BL), 22 diffuse large cell lymphomas (DL) and 1 chronic lymphocytic leukemia (CLL). All 9 FLs and the single BL expressed exclusively cyclin D3, similarly to germinal center B cells, that represent their cells of origin. Six DLs expressed both cyclin D2 and D3, while 6 expressed only D3. Among the 9 pleomorphic T cell lymphomas, medium and large cell type, 5 expressed cyclin D2. Cyclin D3 was also detected in scattered cells in 4 of 9 cases and was highly expressed in 2 of 9 T cell lymphomas. The majority of Hodgkin's lymphomas expressed both cyclin D2 and D3 in Hodgkin/Reed-Sternberg (HRS) cells. The high frequency of positive cells indicates that both cyclins were expressed in the same cells.


Assuntos
Ciclinas/análise , Doença de Hodgkin/patologia , Linfonodos/patologia , Doenças Linfáticas/patologia , Linfoma de Células B/patologia , Linfoma de Células T/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Northern Blotting , Ciclo Celular , Criança , Ciclina D2 , Ciclina D3 , Ciclinas/genética , Feminino , Doença de Hodgkin/genética , Humanos , Hiperplasia , Imuno-Histoquímica , Linfonodos/metabolismo , Doenças Linfáticas/genética , Linfoma de Células B/genética , Linfoma de Células T/genética , Masculino , Pessoa de Meia-Idade
19.
J Gen Virol ; 80 ( Pt 4): 987-995, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10211969

RESUMO

Infection of human B lymphocytes with Epstein-Barr virus (EBV) in vitro induces a G0 to G1 transition followed by DNA synthesis and cell division. The virus activation of the cell cycle closely mimics the antigen-dependent normal B cell activation pathway. Infected B cells undergo blast transformation followed by the emergence of immortalized lymphoblastoid cell lines. Numerous cellular proteins are switched on in the infected cells, including p53. In view of the frequent association of wild-type p53 (wtp53) expression with growth arrest and apoptosis, p53 expression, cell viability (absence of apoptosis) and cell cycle progression at the single cell level during the first week after EBV infection were assessed. The rate of EBV infection was scored by EBNA-5 staining between 20 and 72 h after infection and varied between 20 and 25% of the cell population. All EBNA-5-positive blasts were p53-positive as well. Double staining for p53 and for DNA ends (TUNEL) revealed that p53-positivity and apoptosis were mutually exclusive. Quantification of the DNA content by Hoechst staining and computer-assisted image analysis showed that a fraction of the p53-positive blasts had a DNA content higher than 2N, indicating entry into the S/G2 phases. Double p53 and BrdU staining of the cells, pulse-labelled with BrdU, revealed that 65% of the p53-positive blasts were in S phase 3 days after infection. Similarly, B cell activation by CD40L and IL-4 induced p53 expression without any adverse effect on cell cycle progression. Therefore, the phenomenon is not EBV-specific but correlates with immunoblast activation.


Assuntos
Apoptose , Linfócitos B/virologia , Herpesvirus Humano 4/fisiologia , Proteínas Nucleares , Proteína Supressora de Tumor p53/biossíntese , Linfócitos B/fisiologia , Ligante de CD40 , Divisão Celular , Linhagem Celular , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/análise , Humanos , Interleucina-4/farmacologia , Ativação Linfocitária , Glicoproteínas de Membrana/farmacologia , Proteínas Proto-Oncogênicas/análise , Proteínas Proto-Oncogênicas c-mdm2 , Fase S , Proteína Supressora de Tumor p53/análise
20.
J Hum Virol ; 2(1): 33-7, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10200597

RESUMO

OBJECTIVE: To find cellular proteins that associate with EBNA-3 (also called EBNA-3A), one of the Epstein-Barr virus (EBV)-encoded growth transformation-associated nuclear proteins. METHODS: Screening human cDNA libraries in the yeast two-hybrid system and performing an analysis of interaction in vitro as well as in cell lysates. RESULTS: EBNA-3 binds to the epsilon subunit of the chaperonin containing T-complex protein 1 (epsilon-TCP-1) in the yeast two-hybrid system. The cDNA clone isolated from a human lymphocyte library was found to encode the middle and C-terminal part of epsilon-TCP-1. The interaction was confirmed by showing that a GST fusion protein specifically precipitated EBNA-3 from CV1 cells infected with recombinant vaccinia virus expressing EBNA-3. The interacting region was mapped to the putative apical domain of epsilon-TCP-1. CONCLUSIONS: This study shows that large, virus-encoded transforming proteins such as EBNA-3 may receive help for their initial folding by chaperonin complexes. The recognition of the chaperonin complex likely occurs through specific interaction with one of the subunits. We suggest that nascent EBNA-3 may recognize the TCP-1 complex by interacting with the apical region of the epsilon subunit.


Assuntos
Chaperoninas/metabolismo , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Herpesvirus Humano 4/metabolismo , Chaperonina com TCP-1 , Chaperoninas/genética , Antígenos Nucleares do Vírus Epstein-Barr/genética , Herpesvirus Humano 4/genética , Humanos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
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