An alkaline metallo-proteinase in the human uterine cervix an changes in its activity by cervical ripening

Human uterine cervix at term pregnancy was found to contain an alkaline metallo-proteinase by use of a synthetic substrate, 2,4-dinitrophenyl-L-Pro-L-Gln-Gly-L-Ile-L-Ala-Gly-L-Gln-D-Arg. The enzyme (with a molecular weight of 3.8 . 10(4)) was most active around pH 9.2 toward casein and N alpha-benzoyl-DL-Arg-rho-nitroanilide. [14C]-Gelatin and proteoglycan subunit were also substrates for the enzyme, but [14C]collagen was not. In particular, the enzyme digested gelatin 70-times faster than the novel neutral proteinase in the cervix. Although EDTA was a potent inhibitor, 1,10-phenanthroline, human serum, diisopropylfluorophosphate and elastatinal had no effect on the enzyme. Alkaline proteinase in term pregnant cervices was significantly higher than in non-pregnant ones.     

12-Lipoxygenase activity in human uterine cervix

Homogenates prepared from sections of human uterine cervix or endometrium were incubated with [1-14C]arachidonate and the products examined by radio-TLC. A major product chromatographing with 12-hydroxyeicosatetraenoic acid (12-HETE), and a number of more polar metabolites which were unaffected by 50 microM indomethacin but decreased to the same extent as 12-HETE by 50 microM nordihydroguaiaretic acid, were demonstrated by this technique. The addition of glutathione to the incubation mixture increased the production of 12-HETE, with a proportional decrease in the polar products. There was a large variation in 12-lipoxygenase activity measured in different cervix samples. The levels of the enzyme in the cervix were similar in two groups of uterine samples classified by the histological appearance of the endometrium as proliferative and secretory. However activity was significantly lower in samples taken from post-menopausal patients compared with pre-menopausal patients.     

Longitudinally and circularly measured EMG activity in the human uterine cervix during labour

The role of the smooth cervical muscle has not yet been sufficiently explored. For that reason cervical EMG was measured during induced labour of several primiparas and multiparas. Three spiral electrodes were placed on the cervix in order to measure the EMG in the longitudinal and circular direction referred to the cervical axis. A quantitative analysis of changes in the amplitude and frequency of the EMG signals was performed by means of the spectral method. It was found that the EMG measured from the two leads differed in unripe cervices in the latent phase of labour. The differences are illustrated by two cases. Some possible explanations for the different activity are discussed.     

Increased platelet activity after termination of prostacyclin infusion into man

Infusion of PGI₂ at a dose of 5 or 10 ng/kg/min during 72 hours into patients with peripheral vascular disease was followed by increased susceptibility of platelets to proaggregatory action of ADP and collagen but not that of arachidonate. The above effects were observed 24 hours after termination of infusion of PGI₂. A tendency to an increased formation of TXA₂ in PRP aggregated by arachidonate was also noticed. Infusion of PGI₂ at a dose of 2 mg/kg/min during 72 hours into the patients caused the decreased platelt aggregability to ADP and arachidonate but not to collagen, and a decreased tendency of production of TXA₂ in PRP aggregated by arachidonate. The existence of a “rebound effect” in platelets after a long term PGI₂ therapy is suggested.     

Cytokeratin expression in squamous metaplasia of the human uterine cervix

The expression of cytokeratin polypeptides in squamous metaplasia of the human uterine cervix was investigated by immunocytochemical labeling with polypeptide-specific antibodies against cytokeratins. Immunofluorescence microscopic examination of cervical tissues using various monoclonal antibodies indicated that squamous cervical metaplasia expresses a unique set of cytokeratin polypeptides, this being distinctively different from that expressed by all of the normal epithelial elements of the exo- and endocervix. The development of metaplastic foci was accompanied by the expression of cytokeratin polypeptide no. 13, which is commonly detected in stratified epithelia, and by a reduction in the level of polypeptide no. 18, which is typical of simple epithelia. The 40-kilodalton cytokeratin (no. 19) described by Moll et al., which is abundant in the columnar and reserve cells of the endocervix, was found throughout the metaplastic lesions. Only in 'well-differentiated' metaplasias did we detect polarity of cytokeratin expression reminiscent of the staining patterns in the exocervix. This was manifested by the exclusive labeling of the basal cell layer(s) with antibodies KB 8.37 and KM 4.62, which stain the basal cells of the exocervix. Furthermore, a comparison of cervical metaplasia with squamous areas occurring within endometrial adenocarcinomas pointed to a close similarity in the cytokeratin expression of the two. We discuss the use of cytokeratins as specific markers of squamous differentiation, the relationships between squamous metaplasia and cervical neoplasia, and the involvement of reserve cells in the metaplastic process.     

Biochemical studies on a 12-lipoxygenase in human uterine cervix

Human uterine cervix possesses a high 12-lipoxygenase activity; this enzyme has been isolated in a purified form from the squamous epithelial region of human cervix and its major properties have been investigated. Enzyme activity was present in all subcellular fractions obtained by centrifugation; the highest specific activity was associated with the microsome fraction (160,000 X g pellet). Purification of the enzyme was achieved by acetone precipitation, ion exchange chromatography on CM-cellulose and affinity chromatography on linoleyl-aminoethyl-Sepharose. The product from the incubation of sodium [1-14C]arachidonate with crude enzyme extracts co-chromatographed with authentic 12-hydroxyeicosatetraenoic acid, but the purified enzyme gave a product that behaved like the 12-hydroperoxy derivative. The enzyme had optimum activity at pH 6.5, a Km of 15 microM for arachidonic acid and was stimulated by ATP and Ca2+. Enzyme activity was inhibited by esculetin, nordihydroguaiaretic acid, eicosatetraynoic acid, detergents at concentrations greater than 0.1% (w/v) and preincubation of substrate with GSH and GSH peroxidase. The occurrence of a high 12-lipoxygenase activity is discussed in relation to the specific physiological functions of this tissue.     

Mesenchymal stem cells isolated from human uterine cervix cancer tissues

In the present study, MSCs (mesenchymal stem cells) were successfully isolated and identified from hUCC (human uterine cervix cancer) tissues. The morphological appearance, immunophenotype, growth curve, cell cycle, cytogenetic features and differentiation potential of these cells were investigated. Results showed that cells isolated from the uterine cervix cancer tissues displayed fibroblast‐like morphology and grew into colonies. Immunophenotyping by flow cytometry revealed that the isolated cells were positive for CD13, CD29, CD44, CD105 and HLA‐I, while negative for CD10, CD14, CD31, CD34, CD38 and HLA‐DR. The cells kept a normal karyotype by chromosome analysis. At the third passage, the percentages of cells in G₀‐/G₁‐, 2‐/M‐ and S‐phase were 84.94, 8.36 and 6.71%, respectively. Under appropriate induction conditions, these cells can differentiate into osteogenic, adipogenic cells and hepatocytes. Taken together, MSCs were confirmed to exist in hUCC tissues, which may provide a new target for clinical cancer therapy.     

Ultrastructural modifications at uterine cervix level induced by human papillomaviruses infections

The paper presents the ultrastructural modifications occurring in uterine cervix epithelium in 10 patients with clinical susceptibility of HPV infections. The presence of viral HPV particles was identified in 5 cases and in 1 case the concomitant presence of both HPV and HSV2 particles was detected. The maximum amount of HPV virions is found in the spinous and superficial layer, particularly in the nucleus, but also in cytoplasm. In all the studied cases, cellular alterations were present in the whole depth of the epithelium. The degree of cellular alterations depends upon the epithelial layer to which they belong and to the stage of the disease as well. Cellular alterations are more pronounced at the level of the spinous and superficial layer being present both in nucleus (chromatin condensations, invaginations of the nuclear membrane, the occurrence of some pseudonuclei) and cytoplasm (intracytoplasmic vacuolizations, the presence of some inclusions). The presence of some giant mono- and binucleated cells as well as the formation of cellular syncytia in case of severe alterations are also reported.     

Sensory nerves and neuropeptides in uterine cervical ripening

At the time of parturition (fetal delivery) the uterine cervix must "ripen," becoming soft, pliable, and dilated to accommodate the fetus' delivery. The fundamental processes underlying cervical ripening remain poorly understood. Knowledge that abundant autonomic and sensory nerves supply the uterine cervix, that transection of afferent nerves supplying the cervix blocks parturition, and that some of the changes in the cervix resemble those seen in inflammatory reactions suggests nerves may have a role in the cervical ripening changes. The present study utilized immunohistochemistry, plasma extravasation, and solution hybridization-nuclease protection assay to elucidate the complement of primary afferent nerves and some receptors in the rat cervix during pregnancy, and to determine if they may have roles in the ripening process at term. This study revealed an abundance of nerves associated with the cervical vasculature and myometrial smooth muscle containing immunoreactivity for substance P, calcitonin gene-related peptide, secretoneurin, and nitric oxide synthase throughout pregnancy. Many of these are small unmyelinated capsaicin-sensitive C-fibers. Substance P- (NK1-) and calcitonin gene-related peptide receptors were apparent on uterine cervix vasculature from pregnant, parturient, and postpartum rats. NK1 receptor mRNA was maximal at 20 days of pregnancy. Plasma extravasation of i.v. administered Evans Blue or Monastral Blue was most pronounced at parturition (shortly after NK1 mRNA is maximal); this was similar to plasma extravasation evoked by i.v. administration of substance P or capsaicin-treatment. This study revealed new data about the nervous system of the rat uterine cervix and that these nerves and their transmitters could very well be part of a neurogenic inflammatory process involved in cervical ripening.