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Biomedical subjects

M Wells

Publications and source records attributed to M Wells.

At least 127 records · Page 7Linked to original sources
PubMed1991

Human papillomavirus type 16 infection of the cervix: a comparison of differing DNA detection modes and the use of monoclonal antibodies against the major capsid protein.

An immuno-peroxidase technique using monoclonal antibodies against the major capsid protein L1 of HPV-16 was compared with dot-blot hybridisation of cervical scrapes and in situ hybridisation of cervical biopsy specimens for HPV-16 DNA. In a series of 20 patients all techniques were specific for HPV-16 infection. Ten patients were positive by dot-blot hybridisation and half of those were positive by in situ hybridisation. Only one of HPV-16 DNA positive cases showed L1 protein expression, apparently shortly after the onset of clinical infection. Whether major capsid protein expression reflects episodes of viral replication deserves further study.

Adult↗
PubMed1991

Current conceptualizations on masochism: genesis and object relations.

Masochism has become one of the most confusing and controversial clinical and diagnostic terms within the psychotherapy literature. When defined, however, as a self-defeating way of loving and individuating, masochism remains a particularly useful clinical construct. This article is designed to: (1) review the literature related to the definition, scope and relevance of masochism; (2) present a descriptive clinical overview of the masochistic personality; (3) describe and discuss the etiology of the disorder and (4) discuss masochistic object choice. Masochists' object relations are characterized by loving objects who give non-love in return in order: (1) to attain fusion with the primary object with whom they feel an impossible separation and (2) to heal a narcissistic injury by making critical and rejecting objects love and approve of them. Masochists tend to choose idealized but unloving partners with whom they behave as caretakers or self-objects. This frequently leads them into relationships with individuals who have borderline and narcissitic character structures. While borderline and narcissistic individuals initially fulfill the masochist's underlying wish for idealized symbiosis, they later recapitulate the erratic environment of the masochist's childhood.

Humans↗
PubMed1991

Malignant fibrous histiocytoma of the gingiva. A clinicopathological study.

A case is reported of malignant fibrous histiocytoma (MFH) of the gingiva. The 65-year-old female presented with a fast-growing mass originating from the left lower gingiva. The tumor measured 15 cm in diameter, occupying the entire oral cavity, protruding outside, and causing a mechanical airway obstruction. It appeared to respond to a 1000 rad single dose of preoperative radiation but recurred soon after composite resection with mandibulectomy, even though surgical margins were reportedly free from microscopic invasion. The patient expired from massive lung metastasis in spite of appreciable local response from treatment. This supports the thesis that MFH is a malignant disease and behaves like any soft-tissue sarcoma, which must be treated aggressively by a combined modality of surgery, radiation, and perhaps chemotherapy.

Aged↗
PubMed1990

Minimal deviation adenocarcinoma (adenoma malignum) of the endocervix: a histochemical and immunohistochemical study of two cases.

The histopathological diagnosis of minimal deviation adenocarcinoma (adenoma malignum) of the endocervix may be difficult. Two cases of minimal deviation adenocarcinoma (MDA) were examined using mucin histochemistry and immunocytochemistry with antibodies to epithelial membrane antigens (HMFG1, Ep1), low-molecular-weight cytokeratins (CAM 5.2), carcinoembryonic antigen (CEA), and alpha-amylase. The results were compared with those for normal endocervical glands. Reactivity for CEA in MDA was focal and would be unreliable for biopsy diagnosis. Both cases of MDA contained abundant neutral mucins and sialomucins, whereas sulfomucins were rarely detected; this pattern contrasted with that of normal endocervix. Neoplastic glandular epithelial cells in MDA consistently showed both luminal and cytoplasmic reactivity with Ep1 and HMFG1, whereas normal cervix showed luminal labeling only. Thus, mucin histochemistry and immunohistochemical detection of epithelial membrane antigens may distinguish between extremely well differentiated neoplastic glands in MDA and normal endocervical glands, and hence may aid diagnosis in biopsy specimens.

Adenocarcinoma↗
PubMed1990

Immunolocalization of alpha-amylase in ovarian mucinous tumours.

The distribution of alpha-amylase was studied immunohistochemically in 42 cases of ovarian mucinous tumour. Intense immunoreactivity for amylase was found in 6 of 8 cases of mucinous cystadenocarcinoma. In contrast, only 6 of 20 benign mucinous cystadenomas showed immunoreactive amylase, which was weak and patchy. Mucinous cystadenomas of borderline malignancy showed an intermediate degree of amylase immunoreactivity. The patterns seen are very similar to those reported in normal endocervix, cervical glandular atypia, and invasive adenocarcinoma and suggest molecular as well as morphologic similarities in neoplasia at these sites.

Cystadenocarcinoma↗
PubMed1990

Demonstration of multiple HPV types in normal cervix and in cervical squamous cell carcinoma using the polymerase chain reaction on paraffin wax embedded material.

The prevalence of human papilloma virus (HPV) types 6, 11, 16 and 18 was investigated using the polymerase chain reaction on formalin fixed, paraffin wax embedded material in 19 cases of cervical squamous cell carcinoma and in 10 normal cervices. HPV DNA was detected in 16 of 19 carcinomas, with multiple types present in 11 of these. HPV 16 or 18, or both, were present in all cases in which HPV was shown. Six of 10 cases of normal cervix contained HPV; five of these contained two or more HPV types, including HPV 16 or 18, or both. This study shows the feasibility of using the PCR on paraffin wax embedded material and indicates a high rate of carriage of multiple HPV types in both normal and neoplastic cervix.

Base Sequence↗
PubMed1990

Application of 1 nm gold probes on paraffin wax sections for in situ hybridisation histochemistry.

An in situ hybridisation technique that uses 1 nm immunogold reagents and silver enhancement was devised to detect biotinylated DNA viral probes in formalin fixed, paraffin wax sections of human cervix. DNA probes labelled with biotin-11-deoxyuridine triphosphate were detected after hybridisation to nucleic acid sequences by an antibiotin antibody, followed by a gold labelled secondary antibody. Silver enhancement then permitted visualisation of the signal at the light microscopic level. The method was reliable and produced less background staining than previously described methods. The signal could be enhanced by epi polarisation microscopy. Furthermore, biotinylated DNA probes may be detected directly by a 1 nm gold labelled goat antibiotin antibody without loss of labelling intensity, and this may be preferable to the longer two layer technique, previously described.

Animals↗
PubMed1990

Demonstration of Epstein-Barr virus in primary brain lymphoma by in situ DNA hybridisation in paraffin wax embedded tissue.

Tumour tissue from 29 patients with primary brain lymphoma was reviewed to determine if there was an aetiological association between Epstein-Barr virus and polyclonal and monoclonal lymphoproliferations. The morphology and immunophenotype in 24 patients for whom paraffin wax embedded tissue was available were studied. A high grade pleomorphic tumour morphology with plasmacytoid features was seen in 13 tumours. Because of the large number of pleomorphic lymphomas, all tumours were examined for the presence of the Epstein-Barr virus genome using in situ DNA hybridisation. A panel of three biotinylated probes to different sequences in the Epstein-Barr virus genome was used. Positive hybridisation with one or more probes was shown in tumours from 11 patients. The remaining tumours gave no hybridisation signal. There was no correlation between positive hybridisation and morphological subtype or clinical outcome.

Adolescent↗
PubMed1990

Effect of ethanol on polyamine synthesis during liver regeneration in rats.

Ethanol consumption retards the hepatic regenerative response to injury. This may contribute to the pathogenesis of liver injury in alcoholic individuals. The mechanisms responsible for ethanol-associated inhibition of liver regeneration are poorly understood. To determine if the antiregenerative effects of ethanol involve modulation of polyamine metabolism, parameters of polyamine synthesis were compared before and during surgically induced liver regeneration in ethanol-fed rats and isocalorically maintained controls. After partial hepatectomy, induction of the activity of ornithine decarboxylase (ODC), the rate limiting enzyme for polyamine synthesis, was delayed in rats that had been fed ethanol. This was correlated with reduced levels of putrescine, ODC's immediate product. Increases in hepatic spermidine and spermine were also inhibited. Differences in ODC activity between ethanol-fed and control rats could not be explained by differences in the expression of ODC mRNA or by differences in ODC apoenzyme concentrations, suggesting that chronic ethanol intake inactivates ODC posttranslationally. Supplemental putrescine, administered at partial hepatectomy and 4 and 8 h thereafter, increased hepatic putrescine concentrations and markedly improved DNA synthesis and liver regeneration in ethanol-fed rats. These data suggest that altered polyamine metabolism may contribute to the inhibition of liver regeneration that occurs after chronic exposure to ethanol.

Animals↗
PubMed1989

Measurement of the S-phase duration in normal and abnormal human endometrium by in vitro double labelling with bromodeoxyuridine and tritiated thymidine.

The duration of the S phase of the cell cycle (ts) in the glands and stroma of normal, hyperplastic, and malignant endometrium was measured in vitro using a double labelling technique. Endometrial organ cultures were incubated sequentially in tritiated thymidine (3HTdR) and bromodeoxyuridine (BrdU) each for 1 h. Labelled cells were visualized in tissue sections using 3HTdR autoradiography and immunohistochemistry with an anti-(BrdU) antibody. Three populations of cells, single labelled with either 3HTdR or BrdU, and double labelled cells, were easily identified and ts was calculated from both the rate of influx into, and efflux out of S. There were no significant differences in ts in the different tissue types or between influx and efflux in the glands. However, in the stroma ts calculated from the rate of efflux was significantly shorter than that calculated from the rate of influx, suggesting that during the cell culture period the rate of cell efflux from S was greater than influx. This is the opposite to what would be expected in an exponentially growing cell population and suggests that there may be an effect from the culturing conditions.

Bromodeoxyuridine↗
PubMed1989

Effect of pituitary gonadotrophins on proliferation of primary cultures of human ovarian stroma.

Proliferation of ovarian stromal cells is a common phenomenon in peri- and post-menopausal ovaries. It is generally assumed to be secondary to the rise in circulating gonadotrophins at the menopause, though the process by which it occurs is poorly understood. This study aimed to examine the effect of menopausal levels of pituitary gonadotrophins on the growth of primary cultures of ovarian stroma. A culture system was developed using primary explants of ovarian stroma on a collagen substrate. The effect of follicle stimulating hormone (FSH; 10(-5) g/l) and luteinizing hormone (LH; 10(-5) g/l) on the proliferation of cultures derived from the cortices and medullae of ten ovaries was evaluated using a dual radiothymidine labelling technique. FSH was stimulatory to cortical cultures from 9/10 ovaries and medullary cultures from 7/10 ovaries, while LH was stimulatory to cortical cultures from 6/9 ovaries and medullary cultures from 5/10 ovaries. The responsiveness of the cultures did not correlate with the degree of hyperplasia in vivo. This study demonstrates that pituitary gonadotrophins may modulate the growth of stromal cells in culture, and thus may play a role in the process whereby stromal proliferation occurs in peri- and post-menopausal ovaries.

Adult↗
PubMed1989

In situ hybridization technique using an immunogold silver staining system.

An in situ hybridization technique using an immunogold silver staining detection system was used to detect biotinylated DNA probes in cultured cells and in formalin-fixed paraffin-embedded tissue. The detection method is rapid, reliable and economical, producing an insoluble signal at the site of hybridization which is visible at low-power light microscopy and which can be enhanced by epipolarization microscopy.

Cell Line↗
PubMed1989

Flow cytometry of normal, hyperplastic, and malignant human endometrium. A study of ploidy and proliferative indices including comparison with in vitro S-phase labeling.

The validity of 48 endometrial proliferative indices derived from flow cytometric deoxyribonucleic acid histograms was tested by comparison with S-phase labeling indices. There was a positive but weak correlation. Despite this correlation, there was a good relationship between the flow cytometric proliferative indices and both the menstrual phase and degree of tissue differentiation in a larger series of 162 normal, hyperplastic, and malignant endometrial specimens examined by flow cytometry alone. Flow cytometric proliferative indices may be useful for prediction of tumor behavior in non-DNA aneuploid endometrial carcinomas that are assessed as being a good prognostic type by other tumor parameters.

Carcinoma↗
PubMed1989

Neuropil vacuolation in brain: a reproducible histological processing artefact.

Vacuolation, affecting principally white matter, in animal brains submitted for diagnostic histopathology was attributed to prolonged holding of fixed tissue in 70 per cent alcohol within an enclosed system automatic tissue processor. The effect was consistently reproduced in calf brains but not in pig brains, suggesting a possible species difference in tissue susceptibility. Also, the degree of vacuolation depended on undetermined processor factors additional to prolonged immersion in 70 per cent alcohol. The artefact resembles forms of intramyelinic oedema and can be avoided by holding tissue in primary fixative.

Animals↗