Activity In Human Amniotic Fluid Research Articles

Seroprevalence of brucellosis among women with miscarriage at Ahmadu Bello University Teaching Hospital, Zaria

Background : Brucellosis in animals has been identified as a common cause of miscarriage. It is the most common zoonotic disease that leads to considerable morbidity in humans. It is rarely diagnosed in hospitals in Nigeria, and debate exists as to whether it is a more common cause of miscarriage in humans compared to other infective agents, especially with the finding of antibrucella activity in human amniotic fluid. Brucellosis in humans is a treatable disease and risk factors for transmission are prevalent in Zaria. Objective : The objective of this study was to determine the seroprevalence of brucellosis among women with miscarriage. Materials and Methods : This was a descriptive cross‑sectional study involving 121 women aged between 15 and 49 years with miscarriage who presented to Ahmadu Bello University Teaching Hospital (ABUTH), Zaria from August 2014 to May 2015. Information on socio‑demographic characteristics, reproductive profile, and risk factors for contracting Brucella infection were obtained using a questionnaire. Blood samples were obtained and analysed for Brucella IgG and IgM using indirect enzyme‑linked immunosorbent assay kits. The data was analysed with SPSS, version 20.0. Results : The mean age of the participating women was 29.07 years [standard deviation (SD) ±6.74]. The seroprevalence of brucellosis was 19.0%; 17.4% of the women had a recent infection, and 1.7% had a chronic infection. Age, history of previous miscarriage, consumption of milk products and consumption of roasted meat/barbecue had positive relationships with recent Brucella infection (χ 2 = 9.706, P = 0.046; χ 2 = 7.300, P = 0.026; χ 2 = 3.169, P = 0.049; χ 2 = 3.012, P = 0.050, respectively). Chronic Brucella infection had a positive relationship with number of pregnancies (χ 2 = 8.036, P = 0.018). Regression analyses showed that age, history of previous miscarriage and history of recent miscarriage in animals reared were positively correlated with Brucella seropositivity and miscarriage (χ 2 = 13.200, P = 0.022; χ 2 = 9.795, P = 0.007; χ 2 = 7.890, P = 0.005, respectively). Conclusion : There is a high prevalence of brucellosis among women with miscarriage in Zaria. The burden of the disease should be appreciated and routinely tested to prevent reoccurrence. Key words : Brucellosis ; miscarriage; prevalence.

Pregnancy Associated Brucellosis

Brucellosis is a zoonotic infection caused by Brucella spp. In endemic countries, the disease does not spare the pregnant. There is evidence that brucellosis can induce abortion in humans. Positive cultures of brucella from human placenta, aborted fetuses, and other products of conception were reported previously. It is speculated that brucellosis causes fewer spontaneous abortions in humans than animals due to the absence of Erythritol in the human placenta and fetus. In addition, the presence of anti-brucella activity in human amniotic fluid may also play a role. Rifampin is considered the mainstay of treatment of brucellosis during pregnancy, in various combinations. In a retrospective study of brucellosis in pregnancy, antepartum treatment with antimicrobial agents was more protective against the occurrence of abortion than no or inadequate treatment. It seems that the incidence of abortion is not different among patients treated with either trimethoprim-sulfamethoxazole with or without rifampicin. With therapy during pregnancy, the overall success rate resulting in normal delivery is 90%. The article discussed few of the patents associated with brucellosis.

Pregnancy Associated Brucellosis

Brucellosis zoonotic infection caused by Brucella spp. In endemic countries, the disease does not spare the pregnant. There is evidence that brucellosis can induce abortion in humans. Positive cultures of brucella from human placenta, aborted fetuses, and other products of conception were reported previously. It is speculated that brucellosis causes fewer spontaneous abortions in humans than animals due to the absence of Erythritol in the human placenta and fetus. In addition, the presence of anti-brucella activity in human amniotic fluid may also play a role. Rifampin is considered the mainstay of treatment of brucellosis during pregnancy, in various combinations. In a retrospective study of brucellosis in pregnancy, antepartum treatment with antimicrobial agents was more protective against the occurrence of abortion than no or inadequate treatment. It seems that the incidence of abortion is not different among patients treated with either trimethoprim-sulfamethoxazole with or without rifampicin. With therapy during pregnancy, the overall success rate resulting in normal delivery is 90%. The article discussed few of the patents associated with brucellosis.

The immunomodulatory activity of human amniotic fluid can be correlated with transforming growth factor-beta 1 (TGF-beta 1) and beta 2 activity.

The role of alphafetoprotein (AFP) in the immunomodulatory activity of amniotic fluids (AF) from normally progressing human pregnancy (weeks 14-16) was investigated. A panel of 42 AF (25% v/v) reduced significantly phytohaemagglutinin (PHA)-induced peripheral blood mononuclear cell (PBMC) proliferation in serum-free cultures with a mean per cent inhibition of 68.4 +/- 5.5%. In contrast, AFP preparations, with one exception (U.AFP), failed to display inhibitory activity. Pretreatment of AF with anti-TGF-beta 1 and beta 2 antibodies used alone resulted in the mean per cent loss of inhibition of 33.1 +/- 3.9% and 52.3 +/- 7.5%, respectively. A summative loss of AF-mediated inhibition was detected when anti-TGF-beta 1 and beta 2 antibodies were used in combination, but immunomodulation was rarely abolished 100% by this treatment. Anti-TGF-beta 2 antibody treatment, unlike anti-TGF-beta 1 antibody treatment, reversed the inhibitory activity of U.AFP. The amount of TGF-beta 1 and beta 2 contained in human AF was studied by growth inhibition of Mv1 Lu cells. The mean levels of TGF-beta 1 and beta 2 in AF were 11 +/- 0.9 U/ml and 2.3 +/- 0.4 U/ml, respectively, which corresponds with a mean per cent inhibition of 49 +/- 4.7%. U.AFP also significantly inhibited Mv1 Lu cell growth. To investigate the mechanism of AF-mediated inhibition, the effect of AF and AFP on IL-2 production by concanavalin A (Con A)-stimulated PBMC blasts was determined by the CTLL-2 cell bioassay. IL-2 production was reduced 55.5% in AF-treated blasts and 61% in U.AFP-treated blasts compared with controls. Our findings indicate that the immunomodulatory activity of human AF can be correlated with TGF-beta 1 and beta 2 and not with AFP, the inhibitory activity of U.AFP preparation reflecting copurifying TGF-beta 2 activity.

A pilot study identifying type V collagenolytic activity in human amniotic fluid.

Amniorrhexis complicates pregnancies if it occurs in a preterm pregnancy or remote from the onset of labor in a term pregnancy. There are different collagen types (I-V) that create the extracellular matrix of the amnion. Collagenases specific to these collagen types, with the exception of type V collagen, are found in human amniotic fluid, fibroblasts, polymorphonuclear leukocytes and bacteria. Type V collagen is a major component of the amniotic basement membrane and is responsible for maintaining a barrier to bacteria and to the loss of amniotic fluid. We sought to find evidence of type V collagenolytic activity in human amniotic fluid obtained from pregnancies in different clinical states.

Evaluation of human fetal urine as a source of amniotic fluid phospholipids.

The accumulation of surface active material in amniotic fluid during gestation is assumed to result from lung fluid secretion through the trachea. Some animal studies, however, have indicated that virtually all of the tracheal fluid is swallowed, whereas little if any enters the amniotic cavity. Following these observations fetal urine has been considered by some authors as an alternative source of amniotic fluid phospholipids. However, the phospholipid content of human fetal urine has not yet been determined. We have determined the L/S ratio and lamellar body concentration in human amniotic fluid and fetal urine obtained during 3 term cesarean deliveries. While both the L/S ratio and lamellar body particle concentration in the amniotic fluid samples were equivalent to values reported in term pregnancies, no measurable lecithin or sphingomyelin peaks were demonstrated in the urine samples and very few, if any, particles were counted. The lack of similarity between determinants of surface activity in human amniotic fluid and fetal urine does not support a major contribution of fetal urine to the phospholipid content of amniotic fluid.

Fetal intestinal and renal origins of trehalase activity in human amniotic fluid

Intestinal and renal trehalase isozymes have been distinguished in normal human amniotic fluid on the basis of their membrane-bound character and isoelectric point (p I). The intestinal trehalase was mostly membrane bound in amniotic fluid and had a p I around 4.60. In contrast, the renal form of trehalase was soluble and had a p I around 4.37. These p I values were consistent with those found in extracts of fetal intestinal (p I 4.60) and renal (p I 4.24) tissues. The determination of trehalase isozyme composition of amniotic fluid from pathological pregnancies with anal imperforation and polycystic kidney disease confirmed our findings on the origin of amniotic fluid trehalase. In the sample from a fetus with anal imperforation, low or absent intestinal trehalase isozyme was observed whereas a higher than normal level of renal trehalase activity was found in a fetus with polycystic kidney disease.

Cholinesterases exhibiting aryl acylamidase activity in human amniotic fluid

Acetylcholinesterase (EC 3.1.1.7) and butyrylcholinesterase (EC 3.1.1.8) in human amniotic fluid were estimated in the presence of selective inhibitors. Amniotic fluid cholinesterases (mixture of acetylcholinesterase and butyrylcholinesterase) purified by procainamide-Sepharose affinity chromatography exhibited aryl acylamidase activity which was sensitive to serotonin inhibition (a property of aryl acylamidases associated with both acetyl- and butyrylcholinesterases) and tyramine activation (shown exclusively by aryl acylamidase associated with butyrylcholinesterase). Tyramine activation was unaffected in the presence of the selective acetylcholinesterase inhibitor BW284C51 whereas it was abolished in the presence of the selective butyrylcholinesterase inhibitor ethopropazine, suggesting the presence of both types of aryl acylamidases in amniotic fluid, one associated with acetylcholinesterase and the other associated with butyrylcholinesterase. Butyrylcholinesterase and the associated aryl acylamidase activity in the affinity purified enzyme was selectively immunoprecipitated by a polyclonal antibody raised against human serum butyrylcholinesterase. Estimation of the activity ratio of acetylcholinesterase to butyrylcholinesterase in a few samples of amniotic fluid showed that this could vary depending on the butyrylcholinesterase arising from contaminating blood in the samples. Gel electrophoresis under non-denaturing conditions and enzyme staining showed that butyrylcholinesterase band was detectable on the gel in all the samples whereas acetylcholinesterase band was below detectable levels in normal samples but visible in samples from pregnancies of neural tube defect fetuses. It is suggested that the use of selective cholinesterase inhibitors along with gel electrophoresis and immunoprecipitation studies may be useful in the assessment of cholinesterase activities in human amniotic fluid.

Detection of Early Pregnancy Factor‐Like Activity in Human Amniotic Fluid

Early pregnancy factor (EPF), an immunosuppressive substance, appears in mammalian maternal serum at a very early stage after fertilization. To investigate the normal distribution of EPF in the human body, the rosette inhibition test has been used to detect EPF in human amniotic fluid. The mean value of rosette inhibition titer (RIT) was significantly higher (5.93 +/- 0.43 SE) in 52 amniotic fluid samples (16-30 weeks' gestation) than in 23 nonpregnant sera (3.54 +/- 0.11), indicating that something in amniotic fluid inhibits rosette formation. This inhibitory factor is recognized as EPF or EPF-like substance for its activity significantly correlated with that of EPF in serum from the same donor (r = 0.756: P less than 10(-6]. The immunological significance of the EPF-like substance in amniotic fluid may be important to the survival of semiallogeneic conceptus.

Detection of early pregnancy factor-like activity in human amniotic fluid

The Taiyuan basin is in the Shanxi rift system of China. Results of tectonic studies indicate that the Moho is uplifted by 2–3 km under the Taiyuan basin. However, there is no quantitative evidence showing whether the rift is still in the status of mantle upwelling. Herein, we estimated mantle upwelling rate of Taiyuan basin by using absolute gravity, GPS, groundwater and GLDAS data in this paper. In order to utilize the absolute gravity measurements in terms of tectonic study it is necessary to reduce all disturbing environmental effects. Many of those can be modeled, such as tide, polar motion, ocean tidal loading and atmospheric mass components. The Taiyuan station located in the Taiyuan basin, and absolute gravity measurements with a FG5 instrument were performed from 2009 to 2014, a secular trend was obtained. In-situ GPS data was used to estimate the vertical motion rate since 2011, and the result indicated a land subsidence. In-situ groundwater level was collected with daily surveys from 2009 to 2015, and local hydrology impact on effect was made. The global terrestrial water storage loading effect on gravity at Taiyuan station was computed by using GLDAS global hydrology model. Furthermore there is a good agreement between GRACE results and GLDAS hydrological model results. Subtracting the gravity change rate attributable to the land subsidence, groundwater level and global hydrology from the absolute gravity change rate, the residual gravity change rate was obtained. It reflects mantle upwelling about 2.1 ± 2.6 cm/yr beneath Taiyuan basin.

Plasminogen activator activity and urokinase inhibitor activity in human amniotic fluid and fetal membranes

This study reports on the presence of latent plasminogen activator (PA) activity in human amniotic fluid (HAF). To measure PA, HAF was incubated with plasminogen, and the formation of plasmin was followed by its ability to cleave globin. The latent proenzyme in HAF was converted to active PA by treatment with sodium dodecyl sulphate (SDS) but not by tryptic digestion. The level of SDS-activatable PA activity in HAF increased with increasing gestational age. In an alternative, direct assay of PA based on its amidolytic activity upon L-pyroglutamyl-glycyl-L-arginine-p-nitroanilide (S-2444), HAF PA activity could be demonstrated even without prior exposure to SDS. Medium conditioned with either chorion or amnion produced PA activity suggesting that HAF PA is derived from the fetal membranes. Treatment of the conditioned medium with SDS or trypsin further increased the enzyme activity. The fetal membranes also produce inhibitory activities towards exogenous trypsin, plasmin, and urokinase. The inhibition of plasmin could be separated from the inhibitory activities towards trypsin and urokinase by DEAE-sephadex ion-exchange chromatography. The function of PA in the normal physiology and in pathological processes involving HAF and the fetal membranes remains to be elucidated.

Leukocyte esterase activity in human amniotic fluid for the rapid detection of chorioamnionitis

Chorioamnionitis plays an important role in perinatal morbidity and mortality. Fast and accurate diagnosis poses a major problem. A prospective study was performed to assess the value of positive leukocyte esterase test (Chemstrip 9) for the diagnosis of chorioamnionitis during labor. We evaluated 21 patients with chorioamnionitis in labor at term and used 21 matched control subjects. The sensitivity and specificity of leukocyte esterase activity were compared with those of amniotic fluid cultures, Gram stains, maternal pyrexia and leukocytosis, and fetal tachycardia. The sensitivity in diagnosing chorioamnionitis was 91% and the specificity was 95%. The use of this test strip could provide a rapid, inexpensive screening test for chorioamnionitis.

Antibacterial activity in human amniotic fluid: dependence on divalent cations.

Antibacterial activity, tested against Bacillus subtilis, was present in all 34 samples of human amniotic fluid collected between 37 and 41 weeks gestation. High-molecular-weight (beta-lysin) antibacterial activity was reduced after treatment with ethylene diamine tetra-acetic acid (EDTA), but not after treatment with 1, 10-phenanthroline or diphenylthiocarbazone. The activity was restored following incubation with magnesium, calcium, or zinc. Low-molecular-weight antibacterial activity (less than 1000 daltons) in acid-alcohol extracts was reduced after treatment with dithizone, but not after treatment with EDTA or 1, 10 phenanthroline. Activity was restored after treatment with manganese, cobalt or zinc. High-molecular-weight (beta-lysin) activity was therefore biochemically similar to serum beta-lysin but biochemically different from the low-molecular-weight antibacterial component of amniotic fluid.

Studies on the procoagulant activity of human amniotic fluid II. The role of factor VII

Partially purified Amniotic Fluid Factor (AFF) is found to directly activate human factor X, with a Km for factor X of 0.37 ± 0.06 M. Added phospholipid has only a slight effect on the activation at low concentrations, and inhibits the reaction at higher concentrations. Both DIPF and PMSF inhibit AFF factor X activation. Although added phospholipid is not required for AFF-activity, phospholipase C rapidly destroys it, indicating the presence of intrinsic phospholipid. Phospholipase C treated AFF releases factor VII activity, which leads to the conclusion that AFF is in fact a thromboplastin: factor VII complex. Both AFF and a human brain thromoplastin factor VII complex prepared in vitro were inhibited by Zn ++ ion, while human brain thromboplastin alone is not. AFF is markedly larger than the human brain thromboplastin-factor VII complex as judged by gel filtration.

Studies on the procoagulant activity of human amniotic fluid I. Stability and coagulation factor requirements

A fraction of human amniotic fluid possessing procoagulant activity was purified 35–70 fold by gel filtration on Sepharose 4B. The activity eluted in the void volume indicating a particle size in excess of 5 x 10 daltons. The amniotic fluid factor (AFF) activity is stabilized on stage in the presence of Ca ++ ions which could not be replaced by Mg ++. Addition of phospholipids resulted in accelerated loss of activity. Steps taken to remove factor VII did not affect the activity, but factor X and V are required.

Endogenous stimulant of prostaglandin endoperoxide synthase activity in human amniotic fluid

In this study we describe the discovery and characterization of a substance in human amniotic fluid that stimulates prostaglandin biosynthesis by a microsome-enriched preparation of bovine seminal vesicles. The stimulatory activity is not retained substantially upon anisotropic ultrafiltration through a filter with a molecular weight exclusion limit of 500. Stimulation of prostaglandin biosynthesis by this substance is time- and concentration-dependent; maximal stimulation of approx. 200% being observed within 20 min of commencing incubation with 1 mi-equivalent of stimulant fraction. Stimulatory activity is demonstrable both in the presence of reduced glutathione (1.3 mM) and l-tryptophan (20 mM), either separately or combined, and in the presence of exogenous arachidonic acid (5–120 μM). In the absence of added cofactors, the stimulatory substance increases the rates of biosynthesis of prostaglandin E 2 and prostaglandin F 2α to equal extents. The amount of stimulatory substance added to incubations is correlated positively with increased oxygen consumption during incubations. The stimulatory substance is stable to heating at 100°C for 10 min but is inactivated substantially (to less than 20% of original activity) by treatment with pronase. It is concluded that human amniotic fluid contains a substance of relatively low molecular weight, which is proteinaceous in character, that stimulates prostaglandin endoperoxide synthase activity.

Antibacterial activity in human amniotic fluid: relationship to zinc and phosphate.

Antibacterial activity, tested with B. subtilis, was present in all 44 human amniotic fluids at between 36 and 42 weeks of pregnancy and was unrelated to gestational age within these limits, or to maternal age or parity. High-molecular-weight (beta-lysin) activity, present in all samples, was directly related to concentration of bound zinc, but not to that of free zinc. Low-molecular-weight antibacterial activity (less than 1000 Daltons) was only present in nine specimens, but sub-threshold concentrations were demonstrable by concentrating the ultrafiltrates in more than half of the remaining specimens. Low-molecular-weight activity in the ultrafiltrates was directly related to the concentration of bound zinc in the original amniotic fluid. Neither high- nor low-molecular-weight antibacterial activities were associated with amniotic fluid phosphate levels.

Functional bacterial opsonic activity of human amniotic fluid

There are some data to suggest that amniotic fluid protects the fetus from invasion by pathogenic bacteria. To examine methods by which amniotic fluid may offer such protection, quantitative antibody, complement activity, and functional opsonic capacity were measured. Immunoglobulins were measured by laser nephelometry and total hemolytic complement was determined by radial diffusion; results suggested activity adequate for bactericidal capacity. The chemiluminescence assay was used to quantitate the functional interaction between polymorphonuclear leukocytes and E. coli, group B streptococci (GBS), or zymosan particles preopsonized with amniotic fluid obtained at different stages of gestation. Results were compared to those for normal serum. Data were analyzed by evaluation of the initial slope, area under the curve, and peak chemiluminescence response. Opsonic activity of amniotic fluid for E. coli and GBS was demonstrated, with E. coli showing greater reactivity (maximum = 15,000 to 25,000 cpm) than GBS (10,000 to 20,000 cpm). Specific, as well as nonspecific, opsonic activity was demonstrated by absorption of amniotic fluid with killed bacteria. Concentration of amniotic fluid did not result in an increase in chemiluminescent activity, which demonstrates that optimal opsonic activity already exists. The classical and alternate pathways of complement were assessed for E. coli and GBS. Preterm amniotic fluid did not differ in response from that of amniotic fluid obtained from term pregnancies. This study demonstrates that amniotic fluid can provide the fetus with protection from bacterial pathogens and delineates mechanisms for such protection.

Phosphoenolpyruvate carboxykinase activity in human amniotic fluid

Amniotic fluid samples obtained from normal pregnancies during gestation were used to quantitate the levels of phosphoenolpyruvate carboxykinase (PEPCK) activity. It is concluded that: (1) PEPCK activity was highest in the amniotic fluid cells of midtrimester pregnancies as compared to those of pregnancies close to term; (2) the activity of PEPCK seen in the amniotic fluid supernatant was about one fourth to one half of that seen in the amniotic cells; (3) the amniotic fluid supernatant PEPCK activity fluctuated very little during the entire gestation.

Copper and ceruloplasmin activity in human amniotic fluid

The variation in the level of copper and ceruloplasmin oxidase activity in human amniotic fluid from 20 weeks' gestation to term was reported. The protein content of amniotic fluid decreased toward term. A definite decreasing trend of concentration of copper, expressed both as nanograms of copper per milliliter of amniotic fluid and nanograms of copper per milligram of protein, was also observed from midgestation toward term. Ceruloplasmin, on the other hand, demonstrated a significant increase from the period 20 to 38 weeks' gestation, with a subsequent decline after 38 weeks.