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O W Tawfik

Publications and source records attributed to O W Tawfik.

11 recordsLinked to original sources
PubMed1996

Tumor necrosis factor-alpha response to infection with Chlamydia trachomatis in human fallopian tube organ culture.

OBJECTIVE: Our purpose was to determine whether tumor necrosis factor-alpha is produced in response to infection with Chlamydia trachomatis in the fallopian tube. STUDY DESIGN: Fallopian tubes were harvested at the time of abdominal hysterectomy and processed by standard tissue culture techniques. Tubal segments were inoculated with Chlamydia trachomatis serotype E/UW-5/CX. At 48 hours of incubation supernatant fluid was assayed for tumor necrosis factor-alpha. Tubal segments were stained for chlamydial inclusions and tumor necrosis factor-alpha by use of immunohistochemical techniques. RESULTS: Mean tumor necrosis factor-alpha levels for infected segments were 92.1 +/- 21.3 pg/ml (mean +/- SEM) and for control segments were 61.9 +/- 13.9 pg/ml (p = 0.03 by paired t test). Tumor necrosis factor-alpha was predominantly localized in the tubal epithelium. CONCLUSIONS: Tumor necrosis factor-alpha is produced in response to chlamydial infection by the human fallopian tube. It is an important proinflammatory cytokine and may promote the production of other cytokines and immune-mediated damage of the fallopian tube.

Chlamydia Infections↗
PubMed1992

Lipohyperplasia of the ileocecal valve.

Submucosal lipohyperplasia of the ileocecal valve (ICV) is reportedly a rarely diagnosed lesion of uncertain significance. Eight cases of ICV lipohyperplasia diagnosed in surgical specimens (seven resections, one biopsy) are reviewed: three cases were associated with right lower abdominal quadrant pain and ICV mass on barium enema or operative examination, two were associated with ICV mucosal acute inflammation and necrosis, and three were incidental in resections for cecal, appendiceal, and sigmoid neoplasia. To evaluate the frequency of ICV lipohyperplasia and any associated processes, a series of 51 autopsies was studied. Regarding lipohyperplasia in these valves, 10 (19.6%) were determined to have none, 14 (27.5%) were mild, 20 (39.2%) were moderate, and 7 (13.7%) were marked cases. Degree of lipohyperplasia correlated statistically with degree of cardiac right ventricular fatty infiltration (p = 0.0001), pancreatic fatty infiltration (p = 0.0314), and greater body weight of patient (p = 0.0009). No definite correlation was demonstrated with left ventricular, adrenal, or lymph node fatty infiltration, or with hepatic fatty change, body height, age of patient, or blood glucose. Various gastrointestinal symptoms and lesions accompanied lipohyperplasia, but no definite causal relationship was identified, except for one case of marked lipohyperplasia associated with marked mucosal necrosis and acute inflammation of ICV. In conclusion, ICV lipohyperplasia is a common finding that occasionally may be associated with clinical symptoms and other valve pathology. It correlates to some extent with right ventricular and pancreatic fatty infiltration and with greater body weight.

Adult↗
PubMed1989

Saccharomyces cerevisiae pneumonia in a patient with acquired immune deficiency syndrome.

The clinical course of a patient with a polymicrobial pneumonia that included Saccharomyces cerevisiae infection is described. S. cerevisiae was recovered from autopsy cultures of the lungs, spleen, oral mucosa, and small intestine, and organisms morphologically consistent with S. cerevisiae were visualized in histologic sections of the lung. The role of this organism as a human pathogen is reviewed.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Epidermal growth factor binding in rat uterus during the peri-implantation period.

The profile of epidermal growth factor (EGF) binding to uterine membranes of rats on Day 1 through Day 7 of pregnancy was studied. The binding was lowest on Day 1 and increased gradually through the pre- and postimplantation periods. Binding affinity of the Day 7 uterine membranes was considerably higher than that of the Day 1. Apparent affinity constants (Ka) of Day 1 and Day 7 membranes were 0.29 X 10(-8) M and 1.03 X 10(-8) M respectively. To our knowledge, this is the first report of the modulation of EGF binding to uterine membranes by progesterone-estrogen interaction during early pregnancy.

Animals↗
PubMed1988

Further evidence for role of leukotrienes as mediators of decidualization in the rat.

Inhibitors of leukotrienes were utilized to investigate the role of leukotrienes (LTs) in the induction of decidualization in the rat. Alzet osmotic minipumps, filled with either FPL 55712 (FPL, a specific antagonist of peptidoleukotrienes), nordihydroguaiaretic acid (NDGA, an inhibitor of LT synthesis) or in combination with leukotriene C4 (LTC4) and/or prostaglandin E2 (PGE2), were instilled at the ovarian end of uterine horns of day 5 pseudopregnant rats. Intraluminal infusion of FPL or NDGA, for 4 days, induced a dose dependent decrease in the uterine wet weights when compared to that induced by the infusion of their corresponding vehicles (1 microliter/h). Furthermore, simultaneous infusion of LTC4 (10 ng/h) with different doses of FPL (1, 0.5, or 0.25 microgram/h) produced an increase in uterine weights as compared to that produced by FPL alone. Maximum response, however, was noted when LTC4 (10 ng/h) was infused with FPL at a rate of 0.5 microgram/h. The infusion of LTC4 (10 ng/h) or PGE2 (1 microgram/h) with NDGA, at 1 and 5 micrograms/h, could not overcome its inhibitory effect on decidualization. On the contrary, a combination of LTC4 (10 ng/h) and PGE2 (1 microgram/h) along with NDGA (5 micrograms/h) significantly increased the uterine weight to a level that was comparable to that induced by the infusion of the vehicle. To determine if the synthesis of PGs and LTs was inhibited by NDGA, one uterine horn was infused with NDGA (5 micrograms/h) and the other horn with the vehicle. The intrauterine infusion of NDGA for 24 h inhibited the release of PGE2, PGF2 alpha, LTC4 and LTB4 as compared to those released by the vehicle-infused horns. These data suggest that both PGs and LTs are required for the induction and progression of decidualization.

Animals↗
PubMed1987

Release of prostaglandins and leukotrienes from the rat uterus is an early estrogenic response.

The early estrogenic responses are considered to be involved in inducing embryo implantation in a progesterone (P4)-primed uterus. Because of their involvement in the process of implantation and decidualization, prostaglandins (PGs) and leukotrienes (LTs) could be the mediators of early estrogenic responses in a P4-primed uterus. Therefore, temporal effects of estrogen on the production and/or release of PGF2, PGF2 alpha, LTB4 and LTC4 by the P4-primed uterus of hypophysectomized rats were examined. Hypophysectomized mature female rats were injected for 4 days with P4 (2 mg/rat, s.c.) or with P4 plus a single injection of estradiol-17 beta (E2) (100 ng or 200 ng/rat, i.v.) on the last day of P4 treatment. In one set of experiments, animals were killed at 0.5, 2, 4, 8, 12 and 30th after the last steroid treatment. The production of PGs and Lts by uterine homogenates was measured by radioimmunoassays (RIAs). The production of PGE2 and PGF2 alpha in P4-treated animals showed peaks at 2, 6 and 12h. The superimposition of E2 on P4 treatment induced a higher production rate of PGE2 and PGF2 alpha at 0.5h and abolished the peaks induced by P4 at 2h, but not the peaks at 6 or 12h. Irrespective of the kind of steroid hormonal treatments, uterine production of LTs showed a rapid decline between 6 and 8h followed by a sharp rise at 12h. The superimposition of E2 on P4-treatment again increased the production rates of LTB4 and LTC4 at early hours, i.e. at 0.5 and 2h, respectively, as compared to P4 treatment only.

Animals↗
PubMed1987

Decidualization in the rat: role of leukotrienes and prostaglandins.

The role of prostaglandins (PGs) and leukotrienes (LTs) in the induction of decidualization in the rat uterus was investigated. In the hypophysectomized progesterone (P4) primed rat, intraluminal infusion for four days by osmotic minipump, of PGE2 (1 ug/h), LTC4 (10 ng/h) or 0.15M saline (1 ul/h) significantly elevated uterine weight when compared to the noninfused horn: all were equally effective. In contrast, simultaneous infusion of PGE2 and LTC4 produced an increase in uterine weight which was markedly higher than any other conditions and the reaction was elicited along the entire length of the uterine horn. Infusion of PGE2, LTC4, a combination of the two or vehicle, into one uterine horn of day-5 pseudopregnant rats elicited a huge decidual response. Infusion of indomethacin, an inhibitor of PG synthesis, FPL 55712 (FPL), an antagonist of LTs, or a combination of these inhibitors evoked a minimal decidual response. In addition, FPL infused along with PGE2 or LTC4 markedly reduced the response that could be induced by these arachidonate metabolites alone. Furthermore, infusion of indomethacin along with LTC4 resulted in a far smaller response than that obtained with LTC4 alone. These results are interpreted to indicate that there is an interaction between LTs and PGs in the induction of the uterine decidual response.

Animals↗
PubMed1986

Partial characterization of uterine cells responsible for suppression of murine maternal anti-fetal immune responses.

Several studies have demonstrated that uterine cells are capable of suppressing in vitro immune responses in a nonspecific manner. Two types of cells have been implicated as responsible for suppression, cells with the features of macrophages and a small lymphocyte-like cell. In the present study the maternal anti-paternal mixed lymphocyte reaction was used to investigate further the characteristics of uterine suppressor cells. Three distinct suppressor cell populations were identified: highly suppressive macrophages, small lymphocyte-like cells, and a morphologically heterogeneous third population of highly suppressive cells. The data from this study suggest that pregnant murine uteri contain a variety of cells capable of discouraging lymphocyte proliferation in vitro.

Animals↗
PubMed1986

Implication of prostaglandin E2 in soluble factor-mediated immune suppression by murine decidual cells.

Cells from the uteri of pregnant mice mediate profound nonantigen-specific and nonmajor histocompatibility complex-restricted immune suppression in vitro. In part, those cells accomplish suppression by releasing soluble suppressor factors. The purpose of the present study was to initiate identification of uterine cell suppressor factors. Immune suppression was assayed by the effect of decidual cells or in vitro generated supernatants of decidual cells on mixed lymphocyte reactions (MLR). The following findings support the designation of prostaglandin E2 (PGE2) as a primary suppressor molecule originating with decidual cells: Suppression mediated by supernatants of decidual cells was relieved by removal of lipids but not proteins; indomethacin, an inhibitor of prostaglandin synthesis, produced partial relief of suppression mediated by uterine cells and totally inhibited soluble suppressor factor generation by those cells; decidual cells produced high levels of both PGE2 and PGF2a; the addition of exogenous PGE2 at levels comparable to those found in the decidual cell supernatants restored suppression by decidual cells and their supernatants whereas the addition of PGF2a had no effect; inhibition of the lipoxygenase pathway of arachidonate metabolism had no effect on cell or supernatant mediated suppression; nonspecific suppressor mechanisms, such as arginine depletion and peroxide generation, were excluded as possible mediators of MLR suppression by decidual cells and their supernatants. Fractionation of decidual cells revealed at least three indomethacin-sensitive cell types: small, lymphocyte-like cells, macrophages, and a third population of large decidual cells that was not identified by specific markers.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Multicentric bilateral renal cell carcinomas and a vascular leiomyoma in a child.

We report a unique case of multicentric bilateral renal cell carcinomas and a simultaneous large renal vascular leiomyoma in an 11-year-old child with sickle cell anemia. The patient presented with several episodes of massive hematuria. Abdominal sonography and computed tomography demonstrated bilateral renal neoplasms and the patient was clinically thought to have bilateral Wilms' tumor. An initial biopsy of the lower pole of right kidney revealed a renal cell carcinoma. Accordingly, bilateral renal angiography followed by right total nephrectomy and left upper pole partial nephrectomy were performed. Pathologic studies showed multicentric, bilateral renal cell carcinomas (two in the right kidney and one in the left kidney), of clear, granular, and oncocytic cell types. A simultaneous large vascular leiomyoma was also present in the right kidney. The smooth muscle nature of the leiomyoma was determined by light microscopy, immunohistology, and electron microscopy. The diagnostic difficulties in distinguishing them from other renal tumors are discussed.

Anemia, Sickle Cell↗