Biomedical subjects

S Tazuke

Publications and source records attributed to S Tazuke.

9 recordsLinked to original sources

PubMed1997

Insulin-like growth factor binding protein-1 at the maternal-fetal interface and insulin-like growth factor-I, insulin-like growth factor-II, and insulin-like growth factor binding protein-1 in the circulation of women with severe preeclampsia.

OBJECTIVES: Preeclampsia is characterized by maternal hypertension, proteinuria, edema, and shallow placental invasion. Insulin-like growth factor binding protein-1, abundant in maternal decidua, is believed to play a role in limiting trophoblast invasiveness. In this study we addressed the hypothesis that this binding protein is aberrantly expressed in preeclampsia. We also investigated circulating levels of insulin-like growth factor-I and insulin-like growth factor-II in subjects with severe preeclampsia compared with controls. STUDY DESIGN: Insulin-like growth factor binding protein-1 was investigated by immunohistochemistry at the maternal-fetal interface of eight pregnancies complicated by severe preeclampsia and six controls between 21 and 34 weeks of gestation. Cell types were identified with use of cell-specific markers. Circulating levels of insulin-like growth factor binding protein-1, insulin-like growth factor-I, and insulin-like growth factor-II in 16 patients with severe preeclampsia and 29 controls at the same gestational age were determined by an immunoradiometric assay and correlated with clinical parameters. Data were analyzed by t test and Pearson's method. RESULTS: Insulin-like growth factor binding protein-1 was highly expressed on syncytiotrophoblasts, cytotrophoblasts, and decidual cells but not on placental fibroblasts. Immunostaining was greater at the maternal-fetal interface in severe preeclamptic patients compared with controls. Circulating insulin-like growth factor binding protein-1 levels in subjects with severe preeclampsia were 428.3 +/- 85.9 ng/ml compared with 76.6 +/- 11.8 in controls (p = 0.0007). Circulating insulin-like growth factor-I levels were 80.9 +/- 17.2 ng/ml compared with 179.4 +/- 28.2 ng/ml in controls (p = 0.0001). In contrast, insulin-like growth factor-II levels were not significantly different in the two groups. In subjects with severe preeclampsia insulin-like growth factor binding protein-1 levels correlated with diastolic blood pressure (r = 0.498, p 0.049) and aspartate transcarbamylase (0.621, p = 0.010). CONCLUSIONS: The abundance of insulin-like growth factor binding protein-1 at the maternal-fetal interface in severely preeclamptic pregnancies suggests that the binding protein may participate in the pathogenesis of the shallow placental invasion observed in this disorder. Low circulating insulin-like growth factor-I and elevated insulin-like growth factor binding protein-1 levels may contribute to restricted placental and therefore fetal growth.

Adolescent↗

PubMed1996

Removal of Adnexal Masses by Operative Laparoscopy During Pregnancy

We evaluated the outcomes of pregnancies in nine women who underwent removal of an adnexal mass by operative laparoscopy during pregnancy. These patients, who would otherwise have undergone exploratory laparotomy, were treated by diagnostic and operative laparoscopy using the carbon dioxide laser and electrocoagulation. Gestational ages ranged from 12 to 22 weeks (mean 15 wks). Indications for the surgery were persistent complex or enlarged adnexal mass (7), painful adnexal mass (1), and acute abdomen and intraabdominal hemorrhage (1). Procedures performed were ovarian cystectomy (7), paratubal cyst removal (1), and evacuation of pelvic hematoma (1). Operating time ranged from 55 to 150 minutes (mean 101 min). Peritoneal washings were always obtained. No tocolytics were used during or after surgery. Normal fetal heart tones were auscultated postoperatively in the recovery room. There were no complications secondary to the surgery. Six women delivered at term with weight appropriate for gestational age (AGA). One patient had premature rupture of membranes at 31 weeks' with delivery of a viable AGA infant by emergency cesarean section. Two patients' pregnancies at 26 and 29 weeks are progressing normally. Operative laparoscopy for certain pelvic pathology may be performed safely with no complications to the pregnancy.

Journal Article↗

PubMed1992

Exogenous estrogen and endogenous sex hormones.

Estrogen replacement therapy is widely used to treat menopausal symptoms and prevent osteoporosis. The mechanism of these and other estrogen effects is currently under investigation. We studied the plasma steroid hormone and sex hormone binding globulin levels in frozen plasma obtained from 977 women aged 50 to 79 years from 1972 to 1974. Almost all of the 301 women who reported current use of noncontraceptive estrogen were taking conjugated estrogen by mouth; none reported use of a progestin. Women taking estrogen were significantly younger, thinner, and more likely to smoke cigarettes than women not taking estrogen. Sex hormone binding globulin and all endogenous hormones except testosterone were negatively correlated with age; estradiol was positively and cortisol and sex hormone binding globulin were negatively associated with obesity. After adjusting for age and obesity, dehydroepiandrosterone sulfate, androstenedione, and free testosterone were significantly lower in women currently taking estrogen than in women not using estrogen. These differences were independent of cigarette smoking. As expected, estrogens (including free estradiol), sex hormone binding globulin, and cortisol levels were higher in treated than untreated women. The possibility that some of the benefits and risks of replacement estrogen are secondary to altered adrenal steroid metabolism and androgen levels needs further evaluation.

Aged↗

PubMed1990

Phase separation in phospholipid bilayers induced by biologically active polycations.

The interaction of various polyionenes with phospholipid bilayer membranes was explored by means of differential scanning calorimetry (DSC) with special reference to their antimicrobial activities. A strong interaction was observed between the polyionenes and acidic phospholipids, whereas zwitterionic phospholipid bilayers were not affected significantly by the polycations. Addition of the polyionenes was found to result in phase separation in mixed bilayer membranes composed of acidic and zwitterionic phospholipids. The ability to induce phase separation strongly depended on the structure of the polyionenes. Polyionenes with rigid spacers were found to be most effective to induce phase separation and to be most active in antimicrobial activity. Polyionenes with rigid and flexible spacers in the alternate fashion exhibited less activities which were similar to those of all flexible spacers. Furthermore, their mode of interaction with bilayers was again similar to those of all flexible spacers. Our results indicate that the rigid spacers are favorable for strong interaction with membranes which are assumed to be the target sites of the polycationic biocides, leading to the higher activity. Other factors affecting both the antimicrobial activity and the mode of interaction with membranes were molecular weight and hydrophobicity. With increasing molecular weight, both the activity and ability to induce phase separation increased. Introduction of hydrophilic groups into the spacers resulted in loss of activity and ability to induce phase separation. The antimicrobial activity and the mode of interaction with membranes were correlated and interpreted on the basis of conformational concept of the polyionenes in solution.

Bacteria↗

PubMed1988

Cigarette smoking and levels of adrenal androgens in postmenopausal women.

An antiestrogenic effect of cigarette smoking has been suggested, principally on the basis of data on premenopausal women. We examined the relation between cigarette smoking and endogenous sex-hormone levels in a population of 233 white, postmenopausal women 60 to 79 years of age. Current cigarette smokers had significantly higher mean plasma levels of the adrenal androgens dehydroepiandrosterone sulfate and androstenedione than nonsmokers. Mean levels for smokers and nonsmokers were 3.1 mumol per liter (116 micrograms per deciliter) and 2.3 mumol per liter (86 micrograms per deciliter), respectively (P less than 0.001), for dehydroepiandrosterone sulfate, and 27.8 nmol per liter (797 pg per milliliter) and 22.5 nmol per liter (643 pg per milliliter), respectively (P = 0.002), for androstenedione. A dose-response relation was apparent for these hormones; mean plasma levels increased concomitantly with cigarette consumption. The differences in hormone levels remained after adjustment for age and body-mass index. Mean levels of estrone, estradiol, testosterone, and sex-hormone-binding globulin did not differ between smokers and nonsmokers. These results suggest that the possible decreased risk of breast and endometrial cancer associated with cigarette smoking may not be mediated through lower levels of endogenous estrogen, at least in postmenopausal women, and they raise questions about the role of androgens in disease mechanisms in older populations.

Adrenal Glands↗

PubMed1986

Polycationic biocides with pendant active groups: molecular weight dependence of antibacterial activity.

Two types of polycations with pendant active groups were synthesized: one is polymethacrylate containing pendant biguanide units, and the other is poly(vinylbenzyl ammonium chloride). The two polycations were found to exhibit higher bactericidal activity against Staphylococcus aureus than the corresponding monomers. Fractionation of the polycations was successfully performed on gel filtration chromatography, and examination of the antibacterial activity against S. aureus of the well-characterized polymer samples with various molecular weights (MW) revealed that the activity was strongly dependent on the MW of the polycations and that there existed an optimal MW range for the cidal action of the polymeric biocides. Experiments on the lysis of protoplasts of Bacillus subtilis in contact with the polycations have shown that target sites of the polycationic biocides are cytoplasmic membranes of bacteria.

Anti-Bacterial Agents↗

PubMed1984

New polymeric biocides: synthesis and antibacterial activities of polycations with pendant biguanide groups.

Acrylate monomers with pendant biguanide groups were successfully synthesized, and their homopolymers and copolymers were prepared with acrylamide. These cationic disinfectants of polymeric forms exhibited high antibacterial activity against gram-positive bacteria, whereas they were less active against gram-negative bacteria. It was found that the activity of the polymeric disinfectants was much higher than that of the monomeric species, and the difference in activity between the polymers and the monomers was discussed on the basis of their contributions to each elementary process of the lethal action.

Anti-Bacterial Agents↗

PubMed1983

Interaction of biologically active molecules with phospholipid membranes. I. Fluorescence depolarization studies on the effect of polymeric biocide bearing biguanide groups in the main chain.

Interaction of poly(hexamethylene biguanide hydrochloride) (PHMB), which is a polymeric biocide bearing biguanide groups in its main chain, with phospholipid bilayers was studied by the fluorescence depolarization method. A strong interaction of PHMB with negatively charged bilayers composed of phosphatidylglycerol(PG) alone or of PG and phosphatidylcholine (PC) was observed, whereas neutral PC bilayers were not affected. On adding PHMB, the fluorescence polarization of diphenylhexatriene embedded in the negatively charged bilayers was reduced to a great extent, especially in the gel phase. This was interpreted in terms of PHMB-induced expansion and fluidization of the bilayer, which enables the probe molecule to undergo less-hindered torsional motion. Similarity between PHMB and polymyxin B in the structure, the mode of action against bacteria and the interaction with lipid membranes is discussed.

Biguanides↗

PubMedDate not supplied

Laparoscopy during pregnancy: a literature review.

OBJECTIVE: To review the literature regarding the role of laparoscopy during pregnancy, particularly adnexal mass and non-obstetric surgery, incorporating the results of a series of 9 cases of laparoscopy during pregnancy at our centers. MATERIALS AND METHODS: A Medline search was performed to review the literature, and the reference lists provided by those articles were further explored for citations regarding laparoscopic adnexal surgery, appendectomy, and cholecystectomy. Our series of 9 patients consisted of pregnant patients with adnexal mass or acute abdomen who would otherwise have undergone exploratory laparotomy. Follow-up data for these 9 cases were collected by office visits, inquiry to the primary referring physicians, and telephone calls to the patient. RESULTS: The literature search yielded 42 additional cases of operative pelvic laparoscopy and 51 cases of abdominal operative laparoscopy (cholecystectomy and appendectomy). The publications, particularly regarding cholecystectomy, were supportive of the laparoscopic approach during pregnancy. All of the patients in our series had favorable outcomes. CONCLUSIONS: Advanced operative laparoscopy has been successfully performed for certain indications during pregnancy.

Adnexal Diseases↗