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T Sauer

Publications and source records attributed to T Sauer.

At least 55 records · Page 3Linked to original sources
PubMed1997

Correlation between polymerase chain reaction and cervical cytology for detection of human papillomavirus infection in women with and without dysplasia.

The aim of this study was to compare the ability of two methods, the polymerase chain reaction (PCR) and cervical cytology, to detect HPV infection. The study population included 222 randomly selected women without dysplasia (controls) and 91 women with histologically confirmed dysplasia (CIN II-III) (cases). In women without dysplasia, 8.6% had cytological signs of HPV infection, whereas 15.3% were HPV DNA positive by PCR. In women with dysplasia, 72.5% had cytological signs of HPV infection, whereas 90.1% were HPV PCR positive. The statistical agreement between the two diagnostic methods was low (controls: kappa = 0.26, cases: kappa = -0.03). In total, PCR failed to detect 17 of 85 women with cytological signs of HPV infection, whereas cervical cytology failed to detect 48 of 116 HPV PCR-positive women. In women with dysplasia, but not in women without dysplasia, the oncogenic HPV types were associated with cytological signs of HPV infection.

Adult↗
PubMed1997

Prognosis of radically operated breast carcinoma patients. A retrospective study of 167 consecutive patients with emphasis on histopathological grading, reproducibility and mean nuclear area.

A retrospective study of 167 consecutive radically treated breast cancer patients with histopathologically confirmed ductal carcinoma is presented. The aim was to establish the prognostic significance and reproducibility of histopathological grading done independently by two pathologists. Further-more, the value of measurements of mean nuclear area (MNA) in the primary tumour was assessed. The two pathologists reviewed the same histological sections using a three-point scoring system based on tubular structures, number of mitoses and nuclear pleomorphism. Grading was identical for 70% of the tumours (Kappa value 0.51). With increasing MNA, the fraction of poorly differentiated tumours increased. In the univariate analysis, tumour-related survival was significantly related to histopathological grading when G3 tumours were compared to G1/G2 tumours (p < 0.05). In the multivariate analysis, tumour size (pT category), lymph-node status and grading were the only significant factors influencing patient outcome (p < 0.05). MNA had no significant prognostic value. A combination of tumour size and histopathological grading identifies a group of node-negative patients (pT2 G2/G3) who may have a less favourable prognosis and for whom adjuvant treatment may be beneficial.

Adult↗
PubMed1996

A population-based case-control study of human papillomavirus-type-16 seropositivity and incident high-grade dysplasia of the uterine cervix.

In order to study the association between seropositivity against human papillomavirus-type-16 capsids and CIN II-III in the general population in ages at which high-grade cervical dysplasia arises, 90 cases and 216 controls participating in a population-based case-control study of incident CIN II-III, were analyzed for the presence of HPV antibodies, HPV DNA and for the influence of behavioral factors. A significantly higher proportion of cases than controls were seropositive. Of HPV-16-DNA-positive cases and controls, 42 and 14% respectively were seropositive. A similar proportion of seropositivity was found among the 172 cytologically normal, HPV-DNA-negative controls. However, seropositivity was closely linked to the sexual history of the women. Logistic-regression analyses, adjusting for sexual behavior, smoking history and educational level, revealed that CIN II-III was associated with HPV-16 seropositivity and with HPV DNA. Controlling for the presence of HPV DNA indicated that antibodies were not independently associated with CIN. The low correlation between the presence of HPV antibodies and DNA, the finding that the association between seropositivity and CIN depended on the presence of HPV DNA, and the association of seropositivity with sexual history, may be explained by serology detecting both past and present persistent infections and presence of HPV DNA, reflecting mostly transient infections in controls and persistent infections in cases.

Adult↗
PubMed1996

Palmitoylation of endothelin receptor A. Differential modulation of signal transduction activity by post-translational modification.

Post-translational modifications such as phosphorylation and palmitoylation play important roles for the function and regulation of receptors coupled to heterotrimeric guanyl nucleotide-binding proteins. Here we demonstrate that the human endothelin receptor A (ETA) incorporates [3H]palmitate. Mutation of a cluster of five cysteine residues present in the cytoplasmic tail of ETA into serine or alanine residues completely prevented palmitoylation of the receptor. The ligand binding affinity of the non-palmitoylated ETA mutants was essentially unchanged as compared to the palmitoylated wild type ETA suggesting that the replacement of the cysteine residues did not alter the overall structure of the receptor. Furthermore, the ligand-induced stimulation of adenylyl cyclase by the mutant ETA was unaffected by the mutation. In contrast, the mutated non-palmitoylated receptors but not the wild type receptor failed to stimulate phosphatidylinositol hydrolysis by phospholipase C activation upon challenge by endothelin-1. Furthermore, the mutant receptors failed to stimulate the ligand-induced transient increase in the cytoplasmic calcium seen with the wild type ETA. Endothelin-1 induced mitogenic stimuli via the wild type receptors but not through the mutated receptors suggesting an important role for phospholipase C in this signal transduction pathway. The differential regulation of distinct signal transduction pathways by post-translational modification suggests that palmitoylation of the ETA provides a novel mechanism of modulating ETA receptor activity.

Amino Acid Sequence↗
PubMed1996

Overexpression of thymidine kinase mRNA eliminates cell cycle regulation of thymidine kinase enzyme activity.

Expression of thymidine kinase (TK) enzyme activity and mRNA is strictly S phase-specific in primary cells. In contrast, DNA tumor virus-transformed cells have enhanced and constitutive levels of TK mRNA during the whole cell cycle. Their TK protein abundance, however, still increases at the G1-S transition and stays high throughout G2 until mitosis. Therefore, post-transcriptional control must account for the decoupling of TK mRNA from protein synthesis in G1. To characterize the underlying mechanism, we studied the consequences of TK mRNA abundance on the cell cycle-dependent regulation of TK activity in nontransformed cells. Constitutive as well as conditional human and mouse TK cDNA vectors were stably transfected into mouse fibroblasts, which were subsequently synchronized by centrifugal elutriation. Low constitutive TK mRNA expression still resulted in a fluctuation of TK activity with a pronounced maximum in S phase. This pattern of cell cycle-dependent TK activity variation reflected the one in primary cell but is caused by post-transcriptional control. Increasing overexpression of TK transcripts after hormonal induction compromised this regulation. At the highest constant mRNA levels, regulation of enzyme activity was totally abolished in each phase of the cell cycle. These data indicate that post-transcriptional regulation of TK is tightly coupled to the amount of mRNA; high concentrations apparently titrate a factor(s) required for repressing TK production during G1 and presumably also G2.

3T3 Cells↗
PubMed1996

Clear cell follicular adenoma of the thyroid: a case report.

A case of clear cell follicular adenoma of the thyroid is presented. The patient presented with a single, hyperactive nodule in the right lobe. The cytologic features include cellular smears with numerous disrupted cells and a granular background. The cytoplasm was abundant, pale grayblue vacuolated or granulated, but not clear. Thyreoglobulin was demonstrated both histologically and ultrastructurally, confirming the follicular-cell derivation of the tumor. Ultrastructurally, the cytoplasm was filled with empty, membrane bound vacuoles. The clear cell change might represent an artifact of formalin fixation and/or the paraffin embedding procedure.

Adenocarcinoma, Clear Cell↗
PubMed1996

Prevalence of human papillomavirus in cervical scrapes, as analyzed by PCR, in a population-based sample of women with and without cervical dysplasia.

HPV is suspected of being a major cause of cancer of the uterine cervix. To understand the risk of disease in the general population of women, it is important to estimate the prevalence of HPV infection in a random population-based sample of women without disease. In this study, a total of 231 randomly selected women without dysplasia (controls) were examined, and compared with 103 women with histologically confirmed CIN II-III (patients). The prevalence of HPV DNA in cervical scrapes was determined by general nested PCR, which was expected to detect any relevant HPV type commonly found in cervical samples. The nested positive samples were typed with type-specific PCR. In the general nested PCR, 15% of the controls were positive, compared to 91% of the patients. In the population-based sample, 2.2% had HPV types 6 and 11 and 10% had types 16, 18, 31, and 33. In both groups, HPV DNA was observed less frequently in women above than below the age of 30. The results are among the few population-based figures on the prevalence of HPV in women, and provide a baseline for understanding the risk of developing cancer of the uterine cervix, and determining the proportion of women to be included in intervention studies.

Adult↗
PubMed1996

Structure, strain and function of the transverse acetabular ligament.

To assess the morphology and function of the transverse acetabular ligament (TAL), its internal structure and insertion sites were analyzed, and its strain was determined during hip joint loading. Fifteen specimens were embedded in methyl methacrylate and cut into 500-micron sections parallel to the inlet of the acetabulum. Polarized light microscopy and contact radiography revealed important differences between the ventral and dorsal attachment of the TAL. Ventrally, the fibers insert close to the labrum, at a rather extensive site consisting of fibrous cartilage. Dorsally, the ligament arises from a wide attachment at the bony region of the posterior horn, where it is continuous with the periosteum and the joint capsule. In a second part of the study, six specimens (four fixed, two fresh) were investigated, using a testing machine to simulate hip joint loading. The strains of the TAL and of two sites of the acetabular labrum were measured with strain gauges. Loads of 10-2,800 N were applied and the degree of rotation of the femoral head was varied. At 400% body weight, the TAL encountered tensile strains of up to 3.7%, but the labrum only of up to 0.5%. The contact areas of the hip joints were determined with a polyether casting material. At 50% body weight they were found to lie in the anterior and posterior aspects of the lunate surface. These results indicate that, due to a natural incongruity, the acetabular notch is widened during loading and the TAL submitted to tension.

Acetabulum↗
PubMed1996

Relationship between intestinal fibrosis and histopathologic and morphometric changes in consequential and late radiation enteropathy.

Intestinal fibrosis is a marked feature of late radiation enteropathy. This study assessed the time dose fractionation relationships of radiation-induced fibrosis in order to elucidate possible pathogenetic mechanisms. In 290 male Sprague-Dawley rats, a loop of small bowel was transposed to the left side of the scrotum. Three weeks later, the transposed segment was irradiated with either single dose or various fractionated regimens. The animals were observed for radiation-induced intestinal complications and killed in groups, 2 and 26 weeks after completion of irradiation. A semiquantitative histopathologic radiation injury score, morphometry of the submucosa, submucosal arterioles, intestinal surface area, and relative collagen content were used as endpoints. Fibrosis, measured by collagen assay and radiation injury score, increased with total dose, increasing fraction size and reduction in overall treatment time. This paralleled the results of morphometric assessment of mucosal surface area. Differences in vascular morphometry were only statistically significant in response to changes in total dose and fraction size and not with changes in overall treatment time. We conclude that fibrosis increases with increasing observation time, increasing fraction size, increasing total dose, and reduction of interfraction interval. Consequential injury, occurring as a result of disruption of mucosal integrity, seems to be an important mechanism for development of intestinal fibrosis. In contrast, vascular injury is relatively independent of this mechanism.

Animals↗
PubMed1995

[Extrapulmonary tuberculosis. An important differential diagnosis in immigrants with suspected malignancy].

The incidence of tuberculous disease is increasing all over the world, mostly in the poor, developing countries, but also in some industrialized countries. In Norway, extrapulmonary tuberculosis is a rare phenomenon. It is found mostly among older Norwegians and in younger immigrants from the third world. Since the disease is rare, it may be overlooked or confused with malignant disease. We describe two patients with unusual forms of extrapulmonary tuberculosis, both mimicking neoplastic disease. The first patient was a 27-year-old woman from South-East Asia, who was operated on for suspected intraductal comedo-type carcinoma of the breast, but histological examination showed tuberculous mastitis. The second patient was a 26-year-old man from East Africa with a medical history indicating intra-abdominal lymphoma. The final diagnosis, however, was mesenteric tuberculous lymphadenitis. Both patients were treated successfully with isoniazid, rifampicin and pyrazinamide.

Abdomen↗
PubMed1995

[Estrogen receptor studies in breast cancer based on histological material. Correlation with results from needle biopsy aspirates and pS2 protein determination].

Oestrogen receptor analyzed in archive, histologic specimens from 57 breast cancers showed a concordance with determination in fresh material of 50 to 60%. This means that about half of the oestrogen receptor positive tumours are "lost" when using histologic specimens. pS2 protein is an indirect marker of a functioning oestrogen receptor and was demonstrated in 84% of the carcinomas, including 15 that were oestrogen receptor positive in cytologic material, but negative in histologic specimens. In cases where only histologic specimens are available for receptor analysis, additional determination of pS2 protein may be useful.

Biopsy, Needle↗
PubMed1995

[Investigation of palpable breast tumours. Patient flow and quality assessment of the tripple diagnostic procedure].

The evaluation of patients with a palpable breast lump includes physical examination, mammography, and fine needle aspiration cytology. Combined use of these diagnostic procedures (triple diagnostic) gives nearly the same degree of accuracy as excisional biopsy with a sensitivity of 97-99% in patients with palpable breast carcinomas. Ultrasonography is a valuable adjunct when mammography is normal or nonconclusive and should be the primary imaging modality in patients under 35 years of age with benign findings on physical examination. Ongoing quality assessment of mammography and ultrasonography is mandatory, since the imaging modalities play a central role in the evaluation of patients with lumps in the breast. There are considerable practical problems associated with the medical audit of the triple diagnostic procedure. Aspects of the evaluation of breast lumps and organization of breast imaging centres are discussed in the light of our own experiences.

Biopsy, Needle↗
PubMed1995

Human papillomavirus and cervical intraepithelial neoplasia grade II-III: a population-based case-control study.

The association between certain human papillomaviruses (HPV) and cervical intraepithelial neoplasia (CIN) is well documented, but there is uncertainty about the strength of association and the role of co-factors is unclear. This population-based case-control study in Norwegian women 20-44 years of age included 103 cases with histologically confirmed CIN II-III and 234 age-matched and randomly selected controls. Cytological specimens from the cervix were analyzed using the polymerase chain reaction (PCR). In all, 91% of the cases and 15% of the controls were HPV DNA positive, giving a crude odds ratio (OR) of 67.2 (95% confidence interval: 28.6-157.5). The association between HPV 16 and CIN II-III was even stronger (crude OR = 123.9; 46.7 - 328.5). In logistic regression analysis, additional to HPV, only a high number of sexual partners and a low educational level contributed independently to the risk. The adjusted OR for the association between HPV and CIN II-III was 72.8 (95% CI: 27.6-191.9). The association between HPV and CIN remains very strong even after adjustment for proposed confounding factors. The results therefore support the role of HPV as a causative agent in the development of CIN.

Adult↗
PubMed1995

Looking for chaos in brain slices.

Many signals measured from the nervous system exhibit apparently random variability that is usually considered to be noise. The development of chaos theory has revealed that such random appearing variability may not, in fact, be random, but rather may be deterministic behavior that can reveal important information about the system's underlying mechanisms. We present some new methods for distinguishing determinism from randomness in experimental data, and we apply these methods to population neural responses recorded from hippocampal tissue slices.

Brain↗
PubMed1995

[Not Available].

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Burial↗