Search PubMed⌕ Search

Biomedical subjects

M Mazor

Publications and source records attributed to M Mazor.

At least 235 records · Page 13Linked to original sources

Bacterial endotoxin and tumor necrosis factor stimulate prostaglandin production by human decidua.

The purpose of these studies was to determine the effect of bacterial endotoxin and tumor necrosis factor (TNF) on prostaglandin (PG) secretion by human decidua. Decidual explants were established from women undergoing elective cesarean sections before the onset of labor. Escherichia Coli endotoxin and purified human recombinant TNF (rh TNF) were incubated with decidual explants. PGF2 alpha and PGE2 biosynthesis was measured by radioimmunoassay. A significant increase in the release of all PGs into the media occurred in response to LPS and TNF. In the setting of an extraamniotic infection, bacterial and host secretory products (TNF) could trigger the onset of labor, activating the decidua to produce PGs.

Decidua↗

Amniotic fluid concentration of 5-hydroxyeicosatetraenoic acid is increased in human parturition at term.

5-hydroxyeicosatetraenoic acid (5-HETE) is an arachidonate lipoxygenase product capable of stimulating uterine contractility in a dose-dependent manner in vitro. The purpose of this study was to determine if spontaneous human labor at term is associated with changes in the concentration of this metabolite in amniotic fluid. Fluid was retrieved from 36 women not in labor and from 30 women in active labor at term. 5-HETE was determined by radioimmunoassay. The median amniotic fluid concentration of 5-HETE of women in labor was significantly greater than that of women not in labor (3538 pg/ml vs. 1977 pg/ml, respectively; p = 0.05). This observation is consistent with activation of the lipoxygenase pathway of arachidonic acid metabolism during spontaneous human parturition at term.

Amniotic Fluid↗

Clinical significance, prevalence, and natural history of thrombocytopenia in pregnancy-induced hypertension.

The purpose of this study was to establish the prevalence and clinical significance of thrombocytopenia in pregnancy-induced hypertension (PIH). Thrombocytopenia, defined as a platelet count less than 100,000/mm3 was found in 11.6% of all patients with PIH. Logistic regression analysis was used to assess the relative contribution of thrombocytopenia, proteinuria, and the degree of hypertension to maternal and perinatal outcome. Thrombocytopenia was the principal contributor to the occurrence of abdominal pain, liver dysfunction, the presence of schistocytes in the peripheral smear, proteinuria, fetal distress, and the requirement for blood transfusions. Thrombocytopenia was also associated with a higher incidence of preterm delivery and intrauterine growth retardation. The nadir platelet count occurred within 48 hours of delivery in 56.7% (21 of 37) of cases. The median number of days for recovery of the thrombocytopenia was 2.0 days (range, 0 to 8 days). In five patients thrombocytopenia preceded the clinical manifestations of PIH. We conclude that thrombocytopenia is an independent and important risk factor for the occurrence of maternal and perinatal complications in PIH.

Abdomen↗

Is genital colonization with Mycoplasma hominis or Ureaplasma urealyticum associated with prematurity/low birth weight?

Mycoplasma species have been implicated in the pathogenesis of prematurity, intrauterine growth retardation, low birth weight (LBW), and preterm premature rupture of membranes. The purpose of this study was to review the available literature to determine whether there is an association between genital colonization with Mycoplasma hominis or Ureaplasma urealyticum and prematurity/LBW. Twelve studies were reviewed: nine cohort studies, two case-control studies, and one randomized clinical trial of treatment. The overall isolation rate of M hominis from the genital tract was 27.2%, whereas that of U urealyticum was 70.4% (cohort studies). Results from the randomized clinical trial showed that treatment did not alter the rate of prematurity in women carrying mycoplasma species in the genital tract. None of the cohort studies supported an association between genital colonization with U urealyticum and prematurity/LBW. Similarly, no association between M hominis and prematurity/LBW could be demonstrated in seven of the eight and in six of the eight cohort studies, respectively. On the other hand, two case-control studies showed an association between U urealyticum colonization and prematurity without an association with M hominis. We conclude that the weight of the evidence does not support an association between genital colonization with mycoplasma species and prematurity/LBW.

Cohort Studies↗

Is there an association between colonization with group B Streptococcus and prematurity?

The purpose of this study was to determine whether there is a relationship between colonization of the genitourinary tract with group B Streptococcus (GBS) and prematurity. A search of the literature was conducted to identify articles addressing this issue. Ten studies provided enough data for a critical review; seven studies focused on genital colonization and three on asymptomatic bacteriuria. An association between cervicovaginal colonization with GBS and prematurity could not be demonstrated in six of the seven studies. However, women with asymptomatic bacteriuria caused by GBS had a higher rate of prematurity than did women without asymptomatic bacteriuria. We conclude that the weight of the available evidence does not support an association between prematurity and GBS colonization of the genital tract in the absence of asymptomatic bacteriuria.

Causality↗

Meta-analysis of the relationship between asymptomatic bacteriuria and preterm delivery/low birth weight.

The relationship between asymptomatic bacteriuria and prematurity/low birth weight (LBW) is still a controversial issue, despite many studies. Meta-analysis, a research tool designed to analyze and combine the results of previous studies, may resolve this discrepancy among contradictory results of clinical trials. The purpose of this study was to examine the relationship between asymptomatic bacteriuria and preterm delivery/LBW using meta-analysis. Reports from the literature were classified according to study design into cohort or randomized-treatment control trials. Meta-analysis of cohort studies showed that untreated asymptomatic bacteriuria during pregnancy significantly increased rates of LBW and preterm delivery. Nonbacteriuric patients had only about two-thirds the risk (typical relative risk = 0.65; 95% confidence interval 0.57, 0.74) of LBW and half the risk (typical relative risk = 0.50; 95% confidence interval 0.36, 0.70) of preterm delivery of those with untreated asymptomatic bacteriuria. These reduced risks correspond to a 3.4 (confidence interval 1.8, 5.0) percentage-point difference in LBW and a 3.8 (1.1, 6.4) percentage-point difference in preterm delivery. The analysis of randomized clinical trials showed that antibiotic treatment significantly reduced the risk of LBW (typical relative risk = 0.56; 95% confidence interval 0.43, 0.73), with a substantial reduction of 6.4 (confidence interval 3.3, 9.5) percentage points in the rate of LBW. We conclude that clinical and epidemiologic evidence indicates a strong association between untreated asymptomatic bacteriuria and LBW/preterm delivery and that antibiotic treatment is effective in reducing the occurrence of LBW.

Anti-Bacterial Agents↗

Plasma and urine beta-thromboglobulin in severe preeclampsia.

Beta-thromboglobulin (BTG) has been shown to be a specific platelet protein and can be used as a marker of platelet activation in preeclampsia. Concomitant studies of BTG levels in plasma and urine were performed with eight primiparous severe preeclamptic patients and eight normal primiparous women matched for age. The mean plasma BTG in the severe preeclamptic patients was 186.62 +/- 29.93 ng/ml, and in the control group 45.38 +/- 31.84 ng/ml. The P-value for the difference was highly significant (P = 0.000). In contrast, the mean urine BTG in the study group was 8.42 +/- 4.61 ng/ml, while the mean value for the control group was similar, 5.00 +/- 3.20 ng/ml. The P-value for the difference was not significant (0.05 less than P less than 0.10). These results show that urinary BTG cannot be considered an indicator of platelet activation in severe preeclampsia. A low urinary BTG concentration in the presence of high plasma BTG levels may rather express renal impairment. Failure of BTG renal clearance would contribute to further raising the level of plasma BTG.

Adult↗

The value and limitations of the Gram stain examination in the diagnosis of intraamniotic infection.

Gram stain examination of amniotic fluid is a method used for the rapid diagnosis of intraamniotic infection in patients with preterm premature rupture of membranes and preterm labor. The management of these patients relies heavily on the Gram stain results. Therefore, it is critical that the diagnostic value and limitations, optimal technique, and outcome correlates be precisely established. Most studies have focused on culture results rather than on Gram stain results to describe neonatal and maternal outcome. However, management is based on the Gram stain because culture results are not immediately available. One hundred eighty-seven amniocenteses were performed in 131 patients with preterm premature rupture of the membranes (n = 90) and preterm labor (n = 41). Spun and unspun Gram stains were performed. Centrifugation of the sample did not improve the sensitivity of the technique significantly. The agreement between the two methods was substantial (kappa index 0.89, p less than 0.001). The sensitivity of the Gram stain was 44.8% and the specificity was 97.6%. The sensitivity of the Gram stain was directly proportional to the number of bacteria present in amniotic fluid. In the presence of greater than 10(5) colony forming units per milliliter, 80% of the Gram stains were positive. The absence of both bacteria and white blood cells in a smear was associated with a negative culture of amniotic fluid in 95% of the cases. Clinical chorioamnionitis was associated with a positive Gram stain of amniotic fluid (p less than 0.001). There was a trend toward a higher incidence of endometritis in patients with a positive Gram stain compared with those with a negative Gram stain (p = 0.07). There was no neonatal infectious morbidity in patients with a true negative Gram stain. Patients with a false negative Gram stain had a 25% incidence of neonatal infectious complications (proved and suspected sepsis).

Adult↗

Plasma antithrombin III levels in pre-eclampsia and chronic hypertension.

Plasma levels of antithrombin III were tested during pregnancy in a control group of normal patients and in a study group that included patients with moderate and severe pre-eclampsia and chronic hypertension. The control group showed mean antithrombin III activity of 97.9 +/- 20.9%, the severe pre-eclamptic patients 22.33 +/- 18.22%, the moderate pre-eclamptic patients 56.0 +/- 7.56%, and the chronic hypertensive patients 77.5 +/- 6.69%. The difference between normal pregnancy and moderate pre-eclampsia was significant at P less than 0.002, normal pregnancy and severe pre-eclampsia P less than 0.002, moderate and severe pre-eclampsia P less than 0.002, chronic hypertension and normal pregnancy P less than 0.1, and chronic hypertension and severe pre-eclampsia P less than 0.002. All the severe pre-eclamptic patients and 2 out of 6 of the moderate pre-eclamptic women were below 55.7% (mean - 2S.D.) of normal antithrombin III activity. Patients with heavy proteinuria had depressed antithrombin III activity. However, chronic hypertensive pregnancies, although rather a small group, had almost normal values of plasma antithrombin III activity. The plasma antithrombin III value may thus help to distinguish between chronic hypertension and severe pre-eclamptic disease.

Adult↗

Puerperal adynamic ileus.

Puerperal adynamic ileus includes acute mild and severe clinical manifestations. Acute severe puerperal adynamic ileus may constitute the clinical indication of a serious underlying disease, such as sepsis, rupture of uterus, intra-abdominal or retroperitoneal bleeding, ureteral pathology, intra-abdominal foreign body and internal diseases. Sometimes the diagnosis requires abdominal and chest X-ray, uterine exploration and intravenous pyelography. Surgical treatment requires proper previous general evaluation; and fluids, electrolytes and plasma should be provided.

Adult↗

Blood supply to the uterus in preeclampsia.

Uterine fundal and low segment arcuate artery velocimetry was studied in normal pregnant women and in severe preeclamptic patients. The waveform velocity of the preeclamptic group revealed large differences between systole and diastole, as well as an increased resistance index. Furthermore, the abnormality was more severe in the fundal than in the low segment arcuate measurement.

Adult↗

Amniotic fluid 5-hydroxyeicosatetraenoic acid in preterm labor.

5-Hydroxyeicosatetraenoic acid (5-HETE) is an arachidonate lipoxygenase product capable of stimulating human uterine contractility in a dose-dependent manner in vitro. The purpose of this study was to determine if preterm labor is associated with changes in the concentration of this metabolite in amniotic fluid. Amniotic fluid was obtained by transabdominal amniocentesis from three groups of women with preterm labor: group 1 - women without intraamniotic infection who responded to tocolysis (n = 32); group 2 - women without intraamniotic infection who failed to respond to tocolysis (n = 22); and group 3 - women with intraamniotic infection (n = 14). 5-HETE was determined by radioimmunoassay. The median amniotic fluid concentration of 5-HETE in women who responded to tocolysis (median = 1412 pg/ml; range: 111-3547) was significantly lower than in women who delivered despite tocolysis (median = 2052 pg/ml; range: 136-7774) and women with intraamniotic infection (median = 1876 pg/ml; range: 543-7033) [p less than 0.05]). No difference in amniotic fluid concentrations' of 5-HETE were found between women in groups 2 and 3 (p greater than 0.05).

Adult↗

Amniotic fluid prostaglandin E2 in preterm labor.

These studies were designed to determine amniotic fluid concentrations of prostaglandin E2 (PGE) in women with preterm labor. Amniotic fluid was retrieved by transabdominal amniocentesis from 68 women with preterm labor (less than 37 weeks). Patients were divided into three groups according to the response to tocolysis and the presence or absence of an intraamniotic infection. Amniotic fluid concentrations of PGE2 were significantly greater in women with preterm labor and intraamniotic infection than in women without infection. Patients unresponsive to tocolysis without intraamniotic infection had a significantly greater concentration of PGE2 in amniotic fluid than those responsive to tocolysis.

Adult↗

Increased amniotic fluid leukotriene C4 concentration in term human parturition.

The purpose of this study was to determine whether parturition is associated with changes in the amniotic fluid concentration of leukotriene C4, an arachidonate lipoxygenase metabolite. Amniotic fluid was collected from 36 women not in labor and from 30 women in active labor with cervical dilation of greater than or equal to 6 cm. The concentration of leukotriene C4 was determined by radioimmunoassay. The median amniotic fluid concentration of leukotriene C4 was greater in laboring women than in nonlaboring women: 121 pg/ml (range, 52 to 261 pg/ml) versus 73.5 pg/ml (range, 6 to 249 pg/ml), respectively (p = 0.0008). These data are consistent with activation of the lipoxygenase pathway during spontaneous parturition at term.

Amniotic Fluid↗

Evidence for a local change in the progesterone/estrogen ratio in human parturition at term.

The purpose of this study was to determine if a local change in the concentrations of estrogen and progesterone occurs in the amniotic fluid during human parturition at term. Amniotic fluid was retrieved from 20 women in active labor and from 20 women not in labor. Patients were matched for maternal age and gestational age. Estradiol, estriol, progesterone, and dehydroepiandrosterone sulfate were measured in amniotic fluid by radioimmunoassay. For women in active labor, the median concentrations (range) of these steroid hormones were 2.4 ng/ml (1 to 9.2 ng/ml), 1661.2 ng/ml (556.6 to 3928.1 ng/ml), 12.3 ng/ml (4.7 to 41.4 ng/ml), and 187.5 ng/ml (61.2 to 470 ng/ml), respectively. The median concentrations (range) for women not in labor were 1.6 ng/ml (0.3 to 5.7 ng/ml), 684.2 ng/ml (70.6 to 2103.1 ng/ml), 13.2 ng/ml (7.5 to 63 ng/ml), and 65.6 ng/ml (20 to 334 ng/ml), respectively. Thus spontaneous human parturition at term was associated with significantly increased amniotic fluid concentrations of estradiol, estriol, and dehydroepiandrosterone sulfate (p = 0.02, p = 0.002, p = 0.003, respectively). The progesterone/estrogen ratios (progesterone/estradiol and progesterone/estriol) were significantly lower for women in active labor compared with those not in labor (p = 0.002 and p = 0.0006, respectively). We conclude that a local change in the progesterone/estrogen ratio occurs during human parturition at term.

Amniotic Fluid↗