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1.
Materials (Basel) ; 15(12)2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35744421

RESUMO

A dynamic viscosity function plays an important role in water hammer modeling. It is responsible for dispersion and decay of pressure and velocity histories. In this paper, a novel method for inverse Laplace transform of this complicated function being the square root of the ratio of Bessel functions of zero and second order is presented. The obtained time domain solutions are dependent on infinite exponential series and Calogero-Ahmed summation formulas. Both of these functions are based on zeros of Bessel functions. An analytical inverse will help in the near future to derive a complete analytical solution of this unsolved mathematical problem concerning the water hammer phenomenon. One can next present a simplified approximate form of this solution. It will allow us to correctly simulate water hammer events in large ranges of water hammer number, e.g., in oil-hydraulic systems. A complete analytical solution is essential to prevent pipeline failures while still designing the pipe network, as well as to monitor sensitive sections of hydraulic systems on a continuous basis (e.g., against possible overpressures, cavitation, and leaks that may occur). The presented solution has a high mathematical value because the inverse Laplace transforms of square roots from the ratios of other Bessel functions can be found in a similar way.

2.
J Perinat Med ; 38(2): 203-7, 2010 03.
Artigo em Inglês | MEDLINE | ID: mdl-20121544

RESUMO

AIMS: To evaluate the arteriovenous (AV) pH difference in cord blood as a possible indicator of fetal O(2)-utilization at delivery. Furthermore to examine which maternal, fetal and obstetrical factors lead to elevated O(2)-utilization. METHODS: In this retrospective study all singleton live births, delivered within a four-month period at the University Hospital in Innsbruck, Austria, were analyzed. In total 491 deliveries were evaluated. Arterial and venous cord blood samples were collected at birth and analyzed by using a Radiometer ABL 510. RESULTS: Spontaneous deliveries showed a highly significant elevation in AV-difference (pH 0.10) as compared to cesarean sections (pH 0.05). In spontaneous births, the AV-difference was high in the case of low arterial cord blood pH (P<0.01), as well as in nuchal cord (P<0.01), high parity (P<0.01), very short labor (P<0.05) and elevated birth size and weight (P<0.05). CONCLUSIONS: As a result of increased fetal stress at birth, spontaneous delivery leads to higher O(2)-utilization than cesarean section, which is detectable in an elevated AV-difference. The AV-difference in combination with absolute pH-values can be used for the objective evaluation of fetal O(2)-utilization and consecutively the fetal stress at birth.


Assuntos
Sangue Fetal/metabolismo , Recém-Nascido/sangue , Oxigênio/sangue , Índice de Apgar , Peso ao Nascer/fisiologia , Gasometria , Feminino , Humanos , Concentração de Íons de Hidrogênio , Modelos Lineares , Gravidez , Estudos Retrospectivos , Artérias Umbilicais/fisiologia , Veias Umbilicais/fisiologia
3.
Reprod Sci ; 14(8): 806-14, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18089599

RESUMO

Type-specific antibodies to human papillomaviruses (HPVs) can be detected in most infected adult patients, and they have virus-neutralizing properties. However, there is a dearth of information on the seroprevalence of maternal and neonatal antibodies to HPV capsid antigens. Sera from 104 mothers, their newborns, and 3 twin pregnancies were analyzed by an enzyme-linked immunosorbent assay (ELISA) for the presence of specific IgG, IgM, and IgA antibodies to virus-like particles of HPV-6, -11, -16, -18, and -31. Maternal IgG positivity rates to HPV types 6, 11, 16, 18, and 31 were 23.1%, 2.9%, 8.7%, 5.8%, and 9.6%, respectively. Neonatal rates did not differ significantly, and individual IgG ELISA values of mothers and their infants and all paired twins showed a very high correlation. In contrast, nearly all IgM and IgA individual values in newborns were designated negative, whereas mothers' positivity rates ranged as high as 19.2%. Infants showed no HPV-related lesions at birth or at 4-year follow-up. Seven of 8 tested children lost IgG HPV antibodies in a follow-up examination. Similar anti-HPV IgG seropositivity in mothers and newborns and a lack of neonatal IgA and IgM together with twin and follow-up results indicate that neonatal IgG is not a sign of intrauterine HPV infection but, rather, maternofetal antibody transmission.


Assuntos
Anticorpos Antivirais/sangue , Papillomaviridae/imunologia , Infecções por Papillomavirus/imunologia , Infecções Tumorais por Vírus/imunologia , Adolescente , Adulto , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Estatísticas não Paramétricas
4.
Am J Obstet Gynecol ; 192(4): 1073-83, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15846183

RESUMO

OBJECTIVE: Antibodies to human papillomavirus are indicative for previous human papillomavirus exposure. Human papillomavirus antibody reactivities to vulvar precancerous lesions were reported poorly, and the role of human papillomavirus in some of these lesions is still unclear. STUDY DESIGN: In a direct enzyme-linked immunosorbent assay, serum samples from 126 healthy control subjects, 97 women with lichen sclerosus with or without squamous hyperplasia, 78 women with vulvar intraepithelial neoplasia, and 16 women with verrucous carcinoma were examined for immunoglobulin G and A antibodies to L1 virus-like particles of genital human papillomavirus types 6, 11, 16, 18, and 31, cutaneous human papillomavirus type 8, bovine papilloma virus, and cottontail rabbit papilloma virus. RESULTS: In lichen sclerosus/squamous hyperplasia with atypia immunoglobulin G and A, antibody positivity rates to high-risk human papillomavirus virus-like particle types 16, 18, and 31 were significantly higher than in the control group and the lichen sclerosus/squamous hyperplasia group without atypia. In patients with vulvar intraepithelial neoplasia I, increased immunoglobulin G antibody prevalences with both high-risk and low-risk human papillomavirus-virus-like particles were detected; whereas in patients with vulvar intraepithelial neoplasia II/III, this was observed only with the human papillomavirus types 16, 18, and 31. When only reactivities with 2 genital human papillomavirus types were compared, percentages of positives to only 1 of these 2 types ranged between 43% and 82%, with regard to all respective positives. CONCLUSION: Our data support the role of high-risk human papillomavirus types, mainly human papillomavirus-16, in the pathogenesis of different vulvar lesions with atypia. Serologically, there are no indications that lichen sclerosus/squamous hyperplasia without atypia is associated with human papillomavirus, but high-risk human papillomavirus in lichen sclerosus/squamous hyperplasia with atypia could play a role in carcinogenesis. High antibody specificity was clearly demonstrated among 5 genital, 1 cutaneous human, and 2 animal papillomavirus types.


Assuntos
Carcinoma de Células Escamosas/patologia , Líquen Escleroso e Atrófico/patologia , Papillomaviridae/imunologia , Infecções por Papillomavirus/diagnóstico , Lesões Pré-Cancerosas/patologia , Neoplasias Vulvares/patologia , Adulto , Idoso , Anticorpos Antivirais/análise , Carcinoma de Células Escamosas/virologia , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Líquen Escleroso e Atrófico/virologia , Pessoa de Meia-Idade , Papillomaviridae/isolamento & purificação , Lesões Pré-Cancerosas/virologia , Probabilidade , Valores de Referência , Estudos Retrospectivos , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Neoplasias Vulvares/virologia
6.
Cancer Res ; 63(21): 7507-14, 2003 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-14612552

RESUMO

Ovarian cancer remains still associated with poor prognosis because it is diagnosed predominantly at advanced stages. Ovarian-specific tumor markers do not yet exist for early detection of the disease. At the search of diagnostic markers for ovarian cancer, proteomic-based approaches have focused on novel investigations of neoplastic processes in tumor patients. Cystic fluids of malignant and benign ovarian tumors and serum from the corresponding patients were collected and processed for two-dimensional gel electrophoresis. Proteins were visualized on the gels by silver staining. At the low molecular mass level between 10 and 20 kDa, selected protein spots were additionally processed for nanospray mass spectrometry and partial amino acid sequencing. For protein identification, the sequencing results were compared with computer information from a protein data bank. Protein patterns from cystic fluids of ovarian carcinomas differed significantly from those of benign cysts and revealed additional polypeptides at low molecular mass level between 10 and 20 kDa. Protein patterns from serum of patients with malignant ovarian tumors also contained additional polypeptides between 10 and 20 kDa that were not detected in serum from patients with benign cysts. The additional proteins in serum were present in similar electrophoretic positions compared with those found in the cystic fluid of the corresponding ovarian carcinomas. Protein spots in the range of 10-20 kDa were selected for partial amino acid sequencing. Two protein spots were identified as calgranulin A and three spots as calgranulin B. Either both proteins or only calgranulin A or B were present in cystic fluid from ovarian carcinomas and serum of the corresponding patients. These two proteins were absent or not detectable in fluid from benign ovarian cysts and in serum from those patients. Our investigations concerning protein patterns in cystic fluid of malignant and benign ovarian tumors provide new information about alterations in protein synthesis linked to neoplastic events of the ovary. With the proteomic strategy, new tumor markers are characterized and may serve for diagnostic purposes of patients with ovarian cancer.


Assuntos
Calgranulina A/metabolismo , Calgranulina B/metabolismo , Líquido Cístico/metabolismo , Neoplasias Ovarianas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Calgranulina A/sangue , Calgranulina B/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Cistos Ovarianos/sangue , Cistos Ovarianos/metabolismo , Neoplasias Ovarianas/sangue
7.
Life Sci ; 72(7): 785-93, 2003 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-12479977

RESUMO

In mice, activation of indoleamine-2,3-dioxygenase (IDO), an enzyme converting tryptophan to N-formyl-kynurenine, was found to be necessary requirement to achieve immunotolerance against the fetus and thus uncomplicated pregnancy. In plasma from 20 healthy pregnant women with singleton pregnancies we consecutively analyzed kynurenine and tryptophan concentrations during pregnancy (1 specimen at each trimester of gestation) and postpartum (week 6). None of the women had any signs of infection at the time of plasma sampling, but the study population was otherwise unselected. The kynurenine to tryptophan ratio (kyn/trp) was calculated as an estimate of IDO activity, and data were compared to concentrations of neopterin and 55kD soluble tumor necrosis factor receptor (sTNF-R55), two indicators of immune activation, and to alanineaminotransferase (ALT) levels. Increasing kynurenine and decreasing tryptophan concentrations were found during pregnancy, data suggesting significant degradation of tryptophan. In parallel, increasing concentrations of immune activation markers neopterin and sTNF-R55 were observed, correlating significantly to kyn/trp. The data point to an involvement of cytokine-induced IDO activation in the degradation of tryptophan observed during pregnancy. After pregnancy, sTNF-R55 and also neopterin concentrations declined, whereas tryptophan concentrations increased, indicating that immune activation and activation-induced tryptophan degradation returned to baseline. By contrast, still increased kynurenine concentrations and also increased kyn/trp point to continuing catabolism of tryptophan. Postpartum elevation of liver enzyme ALT may suggest that increased activity of hepatic tryptophan pyrrolase could be involved in increased conversion of tryptophan despite low degree of immune activation. We conclude that IDO is activated in pregnancy and that the decrease of tryptophan might be related to immune activation phenomena. Sustained increase of kynurenine postpartum seems independent from immune activation process.


Assuntos
Gravidez/sangue , Triptofano/sangue , Adulto , Alanina Transaminase/sangue , Antígenos CD/sangue , Biomarcadores/sangue , Cromatografia Líquida de Alta Pressão , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Cinurenina/sangue , Estudos Longitudinais , Neopterina/sangue , Período Pós-Parto , Trimestres da Gravidez , Receptores do Fator de Necrose Tumoral/sangue , Receptores Tipo I de Fatores de Necrose Tumoral
8.
Adv Exp Med Biol ; 527: 77-83, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15206718

RESUMO

In mice, activation of indoleamine-(2,3)-dioxygenase (IDO), an enzyme converting tryptophan to N-formyl-kynurenine, is required to achieve immunotolerance against the fetus and thus uncomplicated pregnancy. On the other hand, postpartum blues and depression appear to be related to reduced availability of tryptophan and serotonin. In healthy pregnant women with singleton pregnancies we consecutively analyzed kynurenine and tryptophan concentrations during pregnancy and postpartum. The kynurenine to tryptophan ratio (kyn/trp) was calculated as an estimate of IDO activity, and data were compared to concentrations of neopterin and 55kD soluble tumor necrosis factor receptor, two indicators of immune activation, and to alanineaminotransferase (ALT) levels. Increasing kynurenine and decreasing tryptophan concentrations were found during pregnancy. The data confirm earlier results and suggest significant degradation of tryptophan. In parallel, increasing concentrations of immune activation markers neopterin and sTNF-R55 were found, correlating significantly to the kyn/trp. The data point to an involvement of cytokine-induced IDO activation in the degradation of tryptophan observed during pregnancy. After pregnancy, sTNF-R55 and also neopterin concentrations declined, whereas tryptophan concentrations increased, indicating that immune activation and activation-induced tryptophan degradation has ceased. By contrast, still increased kynurenine concentrations and also increased kyn/trp suggest continuing turnover of tryptophan. Because also ALT was increased postpartum, abnormal activity of hepatic tryptophan pyrrolase and possibly other enzymes could be involved. We conclude that the decrease of tryptophan during pregnancy might be related to immune activation phenomena. Sustained increase of kynurenine postpartum seems independent from immune activation process, rather it seems related to abnormal activity of liver enzymes.


Assuntos
Gravidez/metabolismo , Triptofano/metabolismo , Adulto , Alanina Transaminase/sangue , Antígenos CD/metabolismo , Feminino , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase , Cinurenina/metabolismo , Estudos Longitudinais , Neopterina/metabolismo , Período Pós-Parto/imunologia , Período Pós-Parto/metabolismo , Gravidez/imunologia , Receptores do Fator de Necrose Tumoral/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral , Triptofano Oxigenase/metabolismo
9.
Am J Obstet Gynecol ; 186(4): 705-11, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11967495

RESUMO

OBJECTIVE: Infection with high-risk human papillomavirus (HPV) types such as HPV-16 is a major risk factor for the development of cervical cancer. HPV-16 capsid antibodies are detectable in approximately 50% of patients with HPV-16 DNA-positive cervical cancer. We investigated the prognostic significance of HPV capsid antibodies for survival in patients with cervical cancer in comparison with conventional clinicopathologic features such as staging, histologic grading, histology, age, and treatment modality. STUDY DESIGN: Serum samples from 68 patients with cervical cancer and 65 healthy female control subjects were analyzed by enzyme-linked immunosorbent assay for HPV-specific immunoglobulin G (IgG) antibodies to baculovirus expressed HPV-6, HPV-11, HPV-16, and HPV-18 L1 virus-like particles (VLPs). RESULTS: HPV-16 L1 IgG antibodies were detectable in 6 of 65 (9%) of the control subjects and in 19 of 68 (28%) of the patients with cervical cancer (P =.007). In the subgroup of patients with HPV-16 DNA-positive cervical cancer (comprising 50% of the investigated samples), HPV-16 L1 antibodies were detected in 40%. HPV-16 L1 seropositivity was in univariate and multivariate analysis in addition to International Federation of Gynecology and Obstetrics stage, the only independent positive prognostic factor for overall survival (P =.01). CONCLUSION: Antibodies to HPV-16 L1 were found to be an independent prognostic factor for overall survival in patients with cervical cancer. Thus, HPV-16 infection may be involved not only in oncogenesis but also in tumor development and behavior.


Assuntos
Anticorpos Antivirais/sangue , Proteínas do Capsídeo , Proteínas Oncogênicas Virais/imunologia , Neoplasias do Colo do Útero/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Neoplasias do Colo do Útero/mortalidade , Vírion/imunologia
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