Intestinal heterotopia: an unusual cause of vulval ulceration. Case report.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to P Russell.
Explore the source record for details and available documents.
Although individual gamma-crystallins from the human eye lens have not been successfully purified and sequenced, most of the genes coding for these lens-specific structural proteins have been cloned and characterized. To investigate the relationship between these genes and the gamma-crystallins of the human lens, we made use of mouse cell lines which contain stably integrated copies of the coding sequences for three of the human gamma-crystallin genes coupled to the human metallothionein IIA promoter. The proteins produced by these hybrid genes in cell culture were detected immunologically and compared by physical characteristics with the gamma-crystallins from the human lens. The protein encoded by the G3 gene showed properties identical to those of the 21,000-molecular-weight gamma-crystallin from 11-month-old lens. The protein isolated from the cells expressing the G4 gene was similar to a 19,000-molecular-weight lens gamma-crystallin, while gene G5 encodes a highly basic gamma-crystallin which may be synthesized in only limited amounts in the human lens. These correlations provide a basis for future investigations on the relationship between putative mutations in human gamma-crystallin genes and altered proteins in hereditary lens cataracts.
Brenner tumours are now generally regarded as being of ovarian epithelial origin. Most have a limited growth potential and are benign. For this reason they are usually found incidentally at hysterectomy. In common with other epithelial ovarian tumours there is a histopathological spectrum of appearances ranging from benign through borderline to invasive malignancy. In this series all 54 tumours were graded according to the degree of cytological atypia, presence of mitoses and tumour necrosis. Heterogeneity of DNA content was observed in the higher grade tumours, two of the four being diploid and two being aneuploid (all benign tumours being diploid). The presence of aneuploidy correlated with the histological features and a poor clinical prognosis. Immunohistochemical staining for keratoprotein was found to be of limited value in the diagnosis of Brenner tumours and their metastases.
The EDTA-extractable protein (EEP) is a major extrinsic protein of lens membrane. The 35 kilodalton (kDa) polypeptide of the EEP cross-reacted to antibody prepared against calpactin I, a substrate for the src protein and an inhibitor of phospholipase A2. Calpactin I is also thought to play a structural role in linking cytoskeleton to membrane. The 35 kDa protein in bovine lens contained phosphotyrosine residues that can be detected by affinity purified antibody to this moiety. Although there is some microheterogeneity of EEP using two dimensional gel electrophoresis, at least one of the chick polypeptides, immunoreactive for calpactin I, can be phosphorylated in whole lens culture. These results suggest a regulatory function for the EEP in lens.
Lens proteins from the guinea pig (Cavia porcellus) were found to be similar to those of other mammals with the exception of the presence of a previously undescribed constituent comprising about 10% of the total soluble lens proteins. This oligomeric protein is composed of polypeptides with apparent molecular weight of 38,000 and elutes from gel exclusion chromatography columns in the beta H-crystallin fraction. Following purification by ion exchange chromatography an antibody was raised against the protein. Using that antibody and antibodies specific for other crystallins we could detect no cross-reactivity between the guinea pig protein and any other reported lens crystallin. This protein, which we have named zeta (zeta)-crystallin, is the first reported mammalian lens crystallin which is not part of the alpha- or beta-gamma families of crystallins. Unlike all other known mammalian crystallins, which have little or no alpha-helical structure, zeta-crystallin is estimated to be approximately 30-40% alpha-helix.
Explore the source record for details and available documents.
Adaptation ability in the center of vision was tested in diabetic patients treated with pan-retinal photocoagulation for diabetic retinopathy and in normal control subjects. This was accomplished with a specially designed contrast sensitivity testing regimen. Patients with retinopathy showed "hidden" deficits, losses in adaptation ability that could not be measured by standard clinical tests, such as visual acuity. This new test thus quantifies a previously unmeasured visual problem that affects the everyday visual function of these patients.
Explore the source record for details and available documents.
In the fission yeast S. pombe the cdc25+ gene function is required to initiate mitosis. We have cloned the cdc25+ gene and have found that increased cdc25+ expression causes mitosis to initiate at a reduced cell size. This shows that cdc25+ functions as a dosage-dependent inducer in mitotic control, the first such mitotic control element to be specifically identified. DNA sequencing of the cdc25+ gene has shown that it can encode a protein of MW 67,000. Evidence is described showing that cdc25+ functions to counteract the activity of the mitotic inhibitor wee1+, and indicating that both mitotic control elements act independently to regulate the initiation of mitosis.
Malignant tumours yield a high-resolution proton magnetic resonance (MR) spectrum. Fifty-one tumour biopsy specimens from patients with cancer of the ovary or colon were examined by magnetic resonance spectroscopy (MRS) to determine whether it was possible to identify tumour subtypes with metastatic potential. Relaxation parameters (T2) for visible lipid methylene protons were within the range of those measured for three animal metastasis models. Primary carcinomas with metastases gave T2 values greater than 350 ms, whereas carcinomas not associated with known metastases at the time of tumour excision gave a range of values from 150 to 1500 ms. All but two carcinomas gave a long T2 (greater than 350 ms) indicating metastatic potential. The MRS method designated five of six histologically borderline epithelial ovarian tumours as malignant with metastatic potential. MRS may be sensitive enough to detect malignant cells in a tumour which is of intermediate or borderline malignancy by light microscopy. Malignancy without a potential for metastasis is uncommon.
We describe the morphologic characteristics and clinical importance of peritoneal lesions that have the histologic features of endometriosis but are devoid of the pigmented stigmas typical of this disease. A total of 137 laparoscopic biopsy specimens were taken of nonpigmented peritoneal lesions in 77 patients, among whom 70 were infertile. Seventy-three biopsy specimens showed endometrium-like glands and stroma, and another 12 showed only endometrioid stroma; no such histologic features of endometriosis were present in 10 biopsy specimens of normal uterosacral ligament peritoneum (p = 0.005, Fisher's test). Nonpigmented lesions that were commonly endometriotic were: white opacified peritoneum (endometriosis in 81% of n = 52 biopsy specimens), red flamelike lesions (81% of n = 16), and glandular lesions (resembling endometrium at hysteroscopy) (67% of n = 21). Lesions that were sometimes endometriotic were: subovarian adhesions (50% of n = 4), yellow-brown peritoneal patches (47% of n = 19), and circular peritoneal defects (45% of n = 11). However, thickened cribriform peritoneum usually was not endometriotic (9% of n = 11) and vesicular excrescences were, in every case, reactions to oil-based salpingographic medium (n = 5). Six patients underwent another laparoscopy within 6 to 24 months and each had developed pigmented endometriotic lesions in previously nonpigmented but abnormal areas. Visualization of pigment is not necessary to diagnose endometriosis, and definition of its early, nonpigmented appearance keeps the clinical category of "unexplained infertility" exclusive.
Binding of lectins to the water-insoluble fractions from human, monkey and mouse lenses was investigated. Lectins bound to glycoproteins blotted from SDS-polyacrylamide gels onto nitrocellulose paper. Use of multiple lectins showed that glycoproteins with apparent molecular weights of about 120 000 and 90 000 were present in all species. These proteins were found in the urea-insoluble fraction. Multiple lectins also bound to two bands around 67 000 and 63 000 molecular weight in both human and monkey lens fractions as well as a urea-soluble band at about 140 000. A 35 000 MW glycoprotein containing N-acetyl-galactosamine and fucose sugars was present in the capsule-epithelium of monkey lenses but was not detected in cortical or nuclear fractions. Glycoproteins from normal and cataractous mice were identified using this new methodology and compared with previously published work using sodium borohydride labelling of glycoproteins. Because of the numerous glycoproteins that can be detected and the ability to assign sugar residues to individual proteins, the lectin-binding method is a powerful tool to investigate lens glycoproteins.
Three classes of monomeric crystallins separable by SDS gel electrophoresis or by gel filtration have been demonstrated in human lens. In previous studies we have concluded from physico-chemical and immunological data that all three polypeptides are related and should be classified as gamma-crystallins. The present paper presents further evidence supporting this conclusion, but also demonstrates that the 24,000 dalton (24kD) polypeptide corresponds to the beta s-crystallin. beta s-crystallin was purified by classical techniques from bovine lens and was shown to cross-react with a monoclonal antibody specific for the human 24kD polypeptide. This antibody exhibited no reactivity to other crystallin fractions from either bovine or human lenses. The identification of the 24kD polypeptide as beta s was further supported by analysis of the tertiary structures of the molecules by near UV-circular dichroism and by the finding of a blocked amino terminus on the 24kD polypeptide. Our finding that the human beta s (24kD polypeptide) should actually be classified as a gamma-crystallin is fully consistent with recently reported sequence data on bovine beta s-crystallin.
Three young women with galactosaemia presented with amenorrhoea and elevated plasma levels of FSH and LH. Two of these women are sisters and ovarian biopsy confirmed premature ovarian failure in one and resistant ovary syndrome in the other. The history and ovarian histology suggested that the sister with ovarian failure may have progressed through a stage of 'follicle resistance' prior to follicular atresia. All subjects had specific bioassays for LH which were grossly elevated, and higher than the levels recorded by immunoassay.
Explore the source record for details and available documents.
We have estimated the number of axons in the optic nerves of human fetuses ranging in gestational age from approximately 10 to 33 weeks. At 10-12 weeks of gestation there were an estimated 1.9 million axons in the optic nerve. A peak count of 3.7 million axons was obtained from a specimen of 16-17 weeks gestation. The estimated number of axons then declined, stabilizing at an estimated 1.1 million axons by about week 29 of gestation. This figure is in close agreement with an estimate of 1.1-1.3 million optic axons in the human adult optic nerve. The results indicate that at least 70% of optic axons generated during development of the primary visual pathway are lost during fetal life. Part of this loss probably occurs as a result of the refinement of the terminal distribution of ganglion cell projections within their target nuclei. The significance of the relatively prolonged period of axonal loss is discussed.
Protein tyrosine kinase activities were determined in retina and Y-79 retinoblastoma cells. Kinase activity was associated with particulate subcellular fractions. Specific activities were similar in both retina and Y-79 cells; apparent Km values for ATP and casein were also similar. Retinoblastoma-derived growth factor stimulated endogenous protein tyrosine phosphorylation in Y-79 cells significantly more than in retina. Differences in protein tyrosine phosphorylation between retina and Y-79 retinoblastoma appear to be due to differences in regulation of the activity by the growth factor or differences in the endogenous protein substrates present in the Y-79 cells.
Neurogenesis in the ventricular layer and the development of cell topography in the ganglion cell layer have been studied in whole-mounts of human fetal retinae. At the end of the embryonic period mitotic figures were seen over the entire outer surface of the retina. By about 14 weeks gestation mitosis had ceased in central retina and differentiation of photoreceptor nuclei was evident within a well-defined area which constituted about 2% of total retina area. This area was approximately centered on the site of the putative fovea, identified by the exclusive development of cone nuclei at that location. The area of retina in which mitosis had ceased increased as gestation progressed. By mid-gestation mitosis in the ventricular layer occupied about 77% of the outer surface of the retina and by about 30 weeks gestation mitosis in the ventricular layer had ceased. Cell density distributions in the ganglion cell layer were nonuniform at all stages studied (14-40 weeks). Densities were highest at about 17 weeks gestation, and by mid-gestation the adult pattern of cell topography was present with maps showing elevated cell densities in posterior retina and along the horizontal meridian. Cell densities generally declined throughout the remainder of the gestation period, except in the posterior retina, where densities in the perifoveal ganglion cell layer remained high during the second half of gestation. There is a rapid decline in cell density in the foveal ganglion cell layer toward the end of gestation, and it is suggested that the persistence of high densities in the perifoveal region may be related to migration of cells away from the developing fovea. The total population of cells in the ganglion cell layer was highest (2.2-2.5 million cells) between about weeks 18 and 30 of gestation. After this the cell population declined rapidly to 1.5-1.7 million cells. It is suggested that naturally occurring neuronal death is largely responsible for this decline.