Preterm labor and bacterial intra-amniotic infection: arachidonic acid liberation by phospholipase A2 of Prevotella bivia

There is a strong association between preterm labor and infection, presumably through an increase in prostaglandin formation. The studies presented in this report were undertaken to evaluate whether Prevotella bivia, a common anaerobic isolate of intrauterine infection, stimulates arachidonic acid metabolism, as a rate-limiting step for prostaglandin synthesis in the human uterine endometrium. When human uterine endometrial cells prelabeled with [3H]arachidonic acid to an isotopically steady state were exposed to an extract of P. bivia, arachidonic acid liberation was stimulated, accompanied by lysophospholipid formation. Similar stimulatory effect on phospholipid degradation was also observed in the experiment with the bacterial conditioned media which was spent as culture media. These results suggests that P. bivia stimulates endometrial phospholipid metabolism, related with activity of phospholipase A2, which might induce the onset of labor associated with intra-amniotic infection.     

Age-related changes in blood coagulation and fibrinolysis in mice fed on a high-cholesterol diet.

To investigate the pathogenesis of hyperlipidemia-induced atherosclerosis, we examined age-dependent changes in platelet activity, blood coagulation and fibrinolysis in susceptibility to a high cholesterol diet (HCD) feeding in male ICR mice. Pretreatment of platelet-rich-plasma from HCD feeding mice for 3 days with epinephrine (300 microM) resulted in a marked enhancement of adenosine 5'-diphosphate (ADP: 0.1 microM) or collagen (0.7 microgram/ml)-stimulated aggregation compared with the same in control mice. Yohimbine as alpha 2-adrenergic blocker antagonized these aggregations in a dose-dependent manner. A significant increase in plasma total cholesterol and VLDL (very low-density lipoprotein)-LDL (low-density lipoprotein)-cholesterol and the liver/body weight ratio was observed in mice fed on HCD for 3 months (3-month HCD mice). In the early phase of this experiment, a significant increase in fibrinogen was observed. In the middle phase, increases in the activity of antithrombin III (ATIII) and alpha 2-plasmin inhibitor (alpha 2-Pl) followed. Plasminogen content gradually decreased in both normal diet and HCD mice throughout the experiment. The activity of plasminogen activator inhibitor (PAI) decreased in 3-month HCD mice. Morphological observation of the aortic arch from 3-month HCD mice revealed apparent atheromatous plaques not seen in control mice. These results suggest that 3-month HCD mice can be a convenient hyperlipidemia-induced atherosclerotic model and the changes in platelet activity, coagulation and fibrinolysis in the early phase may be a cause of pathologic changes in this model.     

The Investigation of Posttraumatic Pseudoaneurysms in Patients Treated with Nonoperative Management for Blunt Abdominal Solid Organ Injuries

Background

Posttraumatic pseudoaneurysms (PAs) have been recognized as the cause of delayed hemorrhage complicated with nonoperative management (NOM), although the need for intervention in patients with small-sized PAs and the relationship between the occurrence of PAs and bed-rest has been also unclear.

Objectives

The purpose of this study was to investigate the clinical history of small-sized PAs (less than 10 mm in diameter) which occurred in abdominal solid organs, and to analyze the relationship between the occurrence of PAs and early mobilization from bed.

Methods

Sixty-two patients who were successfully managed with NOM were investigated. Mobilization within three days post-injury was defined as “early mobilization” and bed-rest lasting over three days was defined as “late mobilization.” A comparison of the clinical factors, including the duration of bed-rest between patients with and without PAs detected by follow-up CT was performed. Furthermore, a multiple logistic regression model analysis on the occurrence of PAs was performed.

Results

PAs were detected in 7 of the 62 patients. The One patient with PAs measuring larger than 10 mm received trans-arterial embolization, and the remaining six patients with PAs smaller than 10 mm were managed conservatively. Consequently, no delayed hemorrhage occurred, and the PAs spontaneously disappeared in all of the six patients managed without intervention. The multiple regression model analysis revealed that early mobilization was not a significant factor predicting new-onset PAs.

Conclusions

Small PAs can be expected to disappear spontaneously. Moreover, early mobilization is not a significant risk factor for the occurrence of PAs.     

Distinct Roles of Urinary Liver-Type Fatty Acid-Binding Protein in Non-Diabetic Patients with Anemia

BackgroundVarious stresses including ischemia are known to up-regulate renal L-FABP gene expression and increase the urinary excretion of L-FABP. In diabetic patients with anemia, the urinary excretion of L-FABP is significantly increased. We studied the clinical significance of urinary L-FABP and its relationship with anemia in non-diabetic patients.ResultsUrinary L-FABP levels were significantly higher in patients with anemia compared to those in patients without anemia. Similarly, the urinary L-FABP levels were significantly higher in patients with albuminuria compared to those in patients without albuminuria. Urinary L-FABP levels correlated with urinary albumin-to-creatinine ratios, estimated glomerular filtration rates, body mass index, and hemoglobin levels. Multivariate linear regression analysis determined that hemoglobin levels (β = -0.249, P = 0.001) and urinary albumin-to-creatinine ratios (β = 0.349, P < 0.001) were significant predictors of urinary L-FABP levels.ConclusionsUrinary L-FABP is strongly associated with anemia in non-diabetic patients.     

Trophic convergence drives morphological convergence in marine tetrapods

Marine tetrapod clades (e.g. seals, whales) independently adapted to marine life through the Mesozoic and Caenozoic, and provide iconic examples of convergent evolution. Apparent morphological convergence is often explained as the result of adaptation to similar ecological niches. However, quantitative tests of this hypothesis are uncommon. We use dietary data to classify the feeding ecology of extant marine tetrapods and identify patterns in skull and tooth morphology that discriminate trophic groups across clades. Mapping these patterns onto phylogeny reveals coordinated evolutionary shifts in diet and morphology in different marine tetrapod lineages. Similarities in morphology between species with similar diets—even across large phylogenetic distances—are consistent with previous hypotheses that shared functional constraints drive convergent evolution in marine tetrapods.     

Biogas production using anaerobic groundwater containing a subterranean microbial community associated with the accretionary prism

In a deep aquifer associated with an accretionary prism, significant methane (CH₄) is produced by a subterranean microbial community. Here, we developed bioreactors for producing CH₄ and hydrogen (H₂) using anaerobic groundwater collected from the deep aquifer. To generate CH₄, the anaerobic groundwater amended with organic substrates was incubated in the bioreactor. At first, H₂ was detected and accumulated in the gas phase of the bioreactor. After the H₂ decreased, rapid CH₄ production was observed. Phylogenetic analysis targeting 16S rRNA genes revealed that the H₂-producing fermentative bacterium and hydrogenotrophic methanogen were predominant in the reactor. The results suggested that syntrophic biodegradation of organic substrates by the H₂-producing fermentative bacterium and the hydrogenotrophic methanogen contributed to the CH₄ production. For H₂ production, the anaerobic groundwater, amended with organic substrates and an inhibitor of methanogens (2-bromoethanesulfonate), was incubated in a bioreactor. After incubation for 24 h, H₂ was detected from the gas phase of the bioreactor and accumulated. Bacterial 16S rRNA gene analysis suggested the dominance of the H₂-producing fermentative bacterium in the reactor. Our study demonstrated a simple and rapid CH₄ and H₂ production utilizing anaerobic groundwater containing an active subterranean microbial community.     

A New Specimen of Carroll’s Mystery Hupehsuchian from the Lower Triassic of China

A new specimen of an enigmatic hupehsuchian genus is reported. The genus was first recognized by Robert L. Carroll and Zhi-ming Dong in 1991, who refrained from naming it because of the poor quality of the only specimen known at the time. After more than two decades, we finally report a second specimen of this genus, which remained unprepared until recently. The new specimen preserves most of the skeleton except the skull, allowing us to erect a new genus and species, Eretmorhipis carrolldongi. The new species shares many characters with Parahupehsuchus longus, including the strange axial skeleton that forms a bony body tube. However, the body tube is short in the new species, being limited to the pectoral region. The vertebral count and limb morphology considerably differ between the new species and P. longus. The forelimb of E. carrolldongi is markedly larger than its hind limb as in Hupehsuchus nanchangensis but unlike in P. longus. The new species is unique among hupehsuchians in a list of features. It has manual and pedal digits that spread radially, forming manus and pes that are almost as wide as long. The third-layer elements of the dermal armor are unusually large, spanning four vertebral segments, yet there are substantial gaps among them. With the addition of the unique paddle, it is now clear that Hupehsuchia had diverse forelimb morphologies spanning from paddles to flippers, unlike ichthyopterygians that were taxonomically more diverse yet only had flippers.     

An RNA chaperone,AtCSP2, negatively regulates salt stress tolerance

Cold shock domain (CSD) proteins are RNA chaperones that destabilize RNA secondary structures. Arabidopsis Cold Shock Domain Protein 2 (AtCSP2), one of the 4 CSD proteins (AtCSP1-AtCSP4) in Arabidopsis, is induced during cold acclimation but negatively regulates freezing tolerance. Here, we analyzed the function of AtCSP2 in salt stress tolerance. A double mutant, with reduced AtCSP2 and no AtCSP4 expression (atcsp2–3 atcsp4–1), displayed higher survival rates after salt stress. In addition, overexpression of AtCSP2 resulted in reduced salt stress tolerance. These data demonstrate that AtCSP2 acts as a negative regulator of salt stress tolerance in Arabidopsis.