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B Hagmar

Publications and source records attributed to B Hagmar.

At least 37 records · Page 2Linked to original sources
PubMed1995

Human papillomavirus type 16 capsids expose multiple type-restricted and type-common antigenic epitopes.

The study of viral infectivity and detection of viral capsid antigens of the major cervical cancer-associated human papillomavirus (HPV) type, HPV-16, requires knowledge of which epitopes are exposed in clinical specimens of infected tissue or on intact capsids. To define the antigenic epitopes of HPV-16, antisera to 66 overlapping synthetic peptides corresponding to the HPV-16 capsid proteins L1 and L2 and to seven peptide analogues were tested in immunoperoxidase stainings of consecutive sections from formalin-fixed, paraffin-embedded HPV infected tissue. Antisera against eleven different peptides from L1 and against seven different peptides from L2 recognized the HPV capsid antigen. Most epitopes were only found on the capsid antigen of certain genital HPV types, but four antigenic epitopes in L1 were detectable also in cutaneous wart specimens. All antigenic epitopes in L2 were restricted to genital HPV types and four L2 epitopes were only detectable in HPV-16 or HPV-33 positive specimens. The surface exposure of the antigenic epitopes was investigated by comparing the reactivity of the antipeptide antisera with intact or disrupted virions or capsids of HPV-11, HPV-16 and bovine papillomavirus (BPV). Twenty antipeptide sera from L1 and seven antipeptide sera from L2 were reactive with intact HPV-16 capsids at titres up to 1:146,000. Sixteen of these antisera were also reactive with disrupted HPV-16 capsids. Cross-reactivity with disrupted HPV-11 and BPV was detected for eleven and six antisera, respectively, whereas intact HPV-11 or BPV virions showed only weak cross-reactivity. In conclusion, the HPV-16 L1 and L2 capsid proteins contained multiple antigenic epitopes, most of which were shared with one or several additional HPV types.

Amino Acid Sequence↗
PubMed1995

Inflammatory signs in wet smear and Pap-smear compared with the histopathology from the female lower genital tract.

In order to define the relationship between various criteria of female lower genital tract inflammation, we examined wet smears, cervical smears and biopsies from 131 patients. The presence of clue cells in rehydrated dry smears showed a positive correlation to the presence of clue cells in Papanicolaou stained smears, and to some extent with cytological evidence of inflammation (Kappa 0.48). Cytological inflammatory findings correlated well with the presence of clue cells in rehydrated dry smears, but signs of inflammation diagnosed by histopathology did not correspond to findings in cytological smears, probably because these methods reveal inflammation at different sites.

Analysis of Variance↗
PubMed1994

PCR-RFLP studies on chromosome 3p in formaldehyde-fixed, paraffin-embedded cervical cancer tissues.

Loss of heterozygosity (LOH) has been extensively studied on the short arm of chromosome 3, and functional proofs have been obtained defining a tumor-suppressor locus at 3p21-22. We examined 31 paraffin-embedded cervical cancer samples for LOH, using 5 PCR-primer pairs, located around 3p21. Allele loss was found in 19 out of the 27 informative samples (70%) while 13 out of 23 informative samples (56%) had LOH located at 3p21-22. More of the human papillomavirus (HPV)-positive samples had LOH compared to the HPV-negative samples, giving only a weak association between loss of allele and HPV integration. Modifications of the DNA in the formaldehyde-fixed samples were detected, and further studies will be required to clarify how such artifacts may affect restriction fragment length polymorphism (RFLP) studies on fixed tissues.

Alleles↗
PubMed1994

Fine needle aspiration biopsy for diagnosis and follow-up of prostate cancer. Consensus Conference on Diagnosis and Prognostic Parameters in Localized Prostate Cancer. Stockholm, Sweden, May 12-13, 1993.

Fine needle aspiration biopsy (FNAB) and ultrasound-guided core biopsy using biopty gun both have a high, and approximately equal, accuracy in diagnosing and grading prostate cancer. The TRUS-guided technique provides a better estimation of the tumor extent and to some degree even of capsular involvement. It is therefore a recommendable part of the preoperative evaluation when radical prostatectomy is contemplated. On the other hand, the aspiration technique usually provides more epithelial cells. It entails a significantly lower risk of septic complications and of seeding tumor cells. It has also a lower cost than the core biopsies. The aspiration biopsy can easily be performed repeatedly in the follow-up procedure, which is of particular importance in cases managed with watchful waiting. We recommend the aspiration biopsy for routine use in the diagnostic work-up and follow-up. It is essential that not only the cytologic evaluation but as well the sampling from the prostate is performed with adequate expertise.

Biopsy, Needle↗
PubMed1994

Modifications of human and viral deoxyribonucleic acid by formaldehyde fixation.

BACKGROUND: Formaldehyde reacts with human and viral DNA through interaction with hydrogen bonds, fixation of DNA-protein, and hydroxymethylation of the nucleic acids. Even though most archival tumor tissues are fixed with formaldehyde, little has been done to analyze the consequences of the reaction of formaldehyde with DNA. Misleading results can be obtained from fixed tissue using polymerase chain reaction (PCR) typing or restriction fragment length polymorphism analyses. EXPERIMENTAL DESIGN: We have studied variations in fixation time in various tissues obtained at autopsy and in prostatic carcinoma biopsies to analyze the effects of the formaldehyde fixation. Different PCR-products were studied after different fixation times. RESULTS: DNA from fixed tissues appears to be no more fragmented than the native DNA. Changes in the DNA structure is more important than DNA quantity for performing PCR on fixed tissues. PCR products longer than 2 to 300 bp was difficult to amplify from some tissues. Only 8 hours of fixation can be enough to inhibit amplification of more than 421 bp. Tissue fixed for longer than 215 hours cannot be amplified for more than 200 basepair products unless excessive numbers (50-80) of PCR-cycles are used. CONCLUSIONS: The loss of PCR product is related to fixation time and PCR-product-length, probably because of the rate of denaturation followed by modification of DNA. Contrary to what has previously been assumed, formaldehyde neither fragments nor reduces the quantity of DNA, but rather changes the structure of DNA. Different tissues may also react differently with formaldehyde, in part because of different tissue fixation gradients. When the PCR product is shorter than 200 bp, DNA isolated from paraffin-embedded tissues fixed with 4% formaldehyde can be useful to any kind of PCR product analysis.

Base Sequence↗
PubMed1993

A longitudinal follow-up of bacterial vaginosis during pregnancy.

Bacterial vaginosis (BV) has been considered by many investigators to be a risk factor for preterm labor. We have followed vaginal pH and the persistence of clue cells in Papanicolaou stained smears in 119 pregnant women during the course of pregnancy. Of 19 patients with clue cells in their smears during the first trimester, 11 (58%) still had clue cells at the second visit during the third trimester. Of the 100 patients without clue cells during their first trimester, none exhibited clue cells during the third trimester. If the persistence of clue cells is truly a risk factor for adverse pregnancy outcome, screening in the first trimester would identify a risk group of 15%. This risk group diminishes to 9% at the time of the third trimester. Vaginal pH > 4.5 had a recovery sensitivity of 76% and specificity of 83%. If clue cells can be considered as the identifying standard for bacterial vaginosis, the sensitivity and specificity of pH is 89% and 94%, respectively. The establishment of the diagnosis of BV during pregnancy and, in some cases, the treatment of the condition may be important as routine procedures in the antenatal center.

Adult↗
PubMed1992

The incidence of HPV in a Swedish series of invasive cervical carcinoma.

The incidence of HPV was studied in 71 invasive squamous carcinomas of the cervix using PCR technique. We used primers, which presumably recognize all types of HPV (consensus primers), and also type-specific primers. In situ hybridization was carried out in 24 of the cases. The overall incidence of HPV was 53/71 (75%) of which 5 cases were positive with the consensus primers only. However, 21/71 cases (30%) were negative for the consensus primers but positive for one of the type-specific primer pairs. This finding indicates that subgenomic deletions may have occurred in the viral genome upon integration in the human DNA. In situ hybridization was positive in 14/24 cases (58%), showing excellent correlation with PCR results. The HPV types detected were, in descending order of frequency: type 16 (52%), 31 (23%), 18 (13%), 33 (12%). No cases of HPV type 6 or 11 were found in this series of invasive carcinomas.

Biopsy↗
PubMed1991

Detection of human papillomavirus infection in tissue blocks by in situ hybridization as compared with a polymerase chain reaction procedure.

Tissue blocks from 25 cases of condyloma and/or dysplasia were used for human papillomavirus typing with DNA in situ hybridization, compared with the very sensitive polymerase chain reaction. Only one of these cases was negative with both methods: a case of vaginal "koilocytosis." Polymerase chain reaction, as expected, was the more sensitive method, positive in 24 cases, with seven double infections. In situ hybridization was positive in 18 cases, with only two detected double infections. There was excellent agreement between the two methods in typing results. In all cases in situ hybridization showed a positive reaction in areas of koilocytosis and/or dysplasia.

Biopsy↗
PubMed1991

Arabinogalactan blockade of experimental metastases to liver by murine hepatoma.

Blocking of organ-specific experimental metastasis was investigated in a syngeneic tumor-host system using a new tumor which primarily colonizes the liver upon intravenous injection. The study included systemic treatment with D-galactose and arabinogalactan as well as cell pretreatment with arabinogalactan and two other glycoconjugates. Treatment with arabinogalactan reduced the amount of liver metastases and prolonged the survival times of the animals in both studies. Host treatment was more effective than tumor cell pretreatment. This could be an effect of arabinogalactan blockade of potential liver receptors by covering of galactose-specific binding sites.

Animals↗
PubMed1990

Lectin binding in murine tumour lines with different malignant characteristics. Effect of enzyme (pronase, neuraminidase) treatment on lectin labelling.

We used 5 syngeneic murine tumour systems for studying quantitative lectin surface binding of intact viable tumour cells. We also investigated, for 3 of the tumours, whether the lectin binding sites were susceptible to proteolytic enzyme (pronase) or neuraminidase treatment. There were significant differences between two of the tumour lines in the binding of wheat germ agglutinin (WGA), concanavalin A (ConA). peanut agglutinin (PNA), soybean agglutinin (SBA) and Ulex europeus agglutinin (UEA). There were also variations in lectin binding between the other tumor lines, but these differences were not statistically significant. Lectin binding showed no evident relationship to the malignancy or the metastasis-forming capacity of the respective tumour cell line. Proteolytic treatment, which drastically affects intravenously induced experimental metastasis formation by one of the tumours, caused a decreased binding of SBA, ConA and WGA. Neuraminidase treatment increased both PNA and SBA binding in three different cell lines, presumably by removing sialic acid masking D-galactose and N-acetyl-D-galactose-amine groups.

Animals↗
PubMed1989

[Aspiration cytology in palpable breast changes of the breast. Too many specimens without cell material to examine].

During the first half of 1988, 927 fine needle aspiration cytology samples from palpable non-cystic breast lesions were examined in our laboratory. Among 582 aspirations performed by members of the laboratory medical staff the frequency of technically non-diagnostic specimens was 4.3 per cent, as against 34.2 per cent among 345 referred specimens. In the latter group there was a clear relationship between the frequency of inadequate specimens and experience in aspiration technique as judged from the number of referred specimens from the individual clinician. It is concluded that education and training in aspiration technique is needed to improve the quality of this diagnostic method.

Biopsy, Needle↗
PubMed1989

[Fine needle aspiration cytology of the thyroid. Based on a 5-year case load].

The article describes a follow-up of 595 fine needle aspiration cytology samples of the thyroid gland taken during the five-year periode 1983-87. Of these samples, 133 (22.4%) were unsatisfactory for diagnosis. Among the remaining samples there were seven false negative and two false positive diagnoses of cancer. The false negative diagnoses were due to inadequate cytologic material not representative of the malignant tumor. The false positive diagnoses were due to cytomorphologic misinterpretation.

Biopsy, Needle↗
PubMed1988

Characteristics of two malignant lymphomas in C57B1/6J mice. Cytogenetic changes and the distribution of i.v. transfused tumor cells with and without enzyme (pronase, neuraminidase) treatment.

Two T-cell lymphomas induced by a combination of antigen stimulation and immunosuppression in inbred C57Bl/6J mice, BWL1 and BWL2 (Ryd et al. 1985), were further characterized. Cytogenetically they have the same trisomy 15 abnormality as chemically, virally and radiation induced T-cell lymphomas. Analyses of early and late tumour generations indicate that both tumours are chromosomally stable. After i.v. transplantation, the two tumors grew in a similar manner and preferentially in spleen and liver. Proteolytic treatment of the tumor cells changed the distribution of both lymphomas from the lungs to other organs. Neuraminidase treatment had no such effect on BWL2, but a similar but weaker effect than pronase on BWL1. Our findings support the notion that the distribution of lymphomas are, at least in part, governed by cell-surface characteristics.

Animals↗
PubMed1986

Effects of zinc on tumor transplantability.

The effects of zinc treatment on the transplantability of tumor cells were investigated in two syngeneic murine tumor systems. A 15-min incubation of tumor cells in 0.1 mM zinc caused a dramatic decrease in intravenous transplantability for melanoma B16 cells, while MCG 101-AA cells were unaffected. The subcutaneous transplantability remained unchanged in both cases. In order to elucidate the mechanism responsible for the effect on B16 cells, a number of factors of possible importance for the intravenous transplantability were investigated. Zinc treatment reduced the activity of extracellular neutral protease, and increased the cell rigidity and fragility in a similar way in both cell lines. However, zinc effects on cell adhesion and cell proliferation were different in the two cell lines. It is possible that zinc reduces the intravenous transplantability of melanoma B16 cells by impairment of cell adhesion.

Aminopeptidases↗