Effects of Closed Vs. Open Repeated Endotracheal Suctioning During Mechanical Ventilation on the Pulmonary and Circulatory Levels of Endothelin-1 in Lavage-Induced Rabbit ARDS Model

Background: A growing body of evidence demonstrates discretely the difference of open endotracheal suctioning (OES) and closed endotracheal suctioning (CES) on the respiratory and hemodynamic parameters in acute respiratory distress syndrome (ARDS). Endothelin-1 (ET-1), a mediator of vascular inflammation, cell proliferation, and fibrosis in addition to being a potent vasoconstrictor has been potentially implicated in the pathogenesis of ARDS. Here, we investigated the effects of repeated OES vs. CES during mechanical ventilation on circulatory and pulmonary levels of ET-1 in ARDS. Methods: Briefly, 22 Japanese White Rabbits were intubated with a 3.5-mm endotracheal tube. Normal saline was instilled into lung and washed mildly. After instillation, rabbits were ventilated at definite setting; OES and CES duration was for 6 hours and performed every 30 minutes from protocol start. Results: At circulatory level, either OES or CES did not alter plasma ET-1 level compared to the ET-1 level in ARDS before the initiation of endotracheal suctioning (OES 4.7 ± 1.3 pg/ml vs. CES 4.8 ± 1.5 pg/ml, p=0.839). In contrast, pulmonary ET-1 level was significantly higher in CES group compared to OES group after 6 hours of repeated suctioning in ARDS (OES 26.9 ± 2.2 pg/mg vs. CES 29.9 ± 3.3 pg/mg, p=0.018). This change in pulmonary ET-1 level could maintain a parallel relation with PaO2 level. Conclusion: At this moment, we cannot clarify the mechanism and effects of the observed change in ET-1 in a rabbit model of ARDS as well as its clinical impact.Research Articl

Insights into Land Plant Evolution Garnered from the Marchantia polymorpha Genome.

The evolution of land flora transformed the terrestrial environment. Land plants evolved from an ancestral charophycean alga from which they inherited developmental, biochemical, and cell biological attributes. Additional biochemical and physiological adaptations to land, and a life cycle with an alternation between multicellular haploid and diploid generations that facilitated efficient dispersal of desiccation tolerant spores, evolved in the ancestral land plant. We analyzed the genome of the liverwort Marchantia polymorpha, a member of a basal land plant lineage. Relative to charophycean algae, land plant genomes are characterized by genes encoding novel biochemical pathways, new phytohormone signaling pathways (notably auxin), expanded repertoires of signaling pathways, and increased diversity in some transcription factor families. Compared with other sequenced land plants, M. polymorpha exhibits low genetic redundancy in most regulatory pathways, with this portion of its genome resembling that predicted for the ancestral land plant. PAPERCLIP

Erythrocyte-Rich Thrombus Is Associated with Reduced Number of Maneuvers and Procedure Time in Patients with Acute Ischemic Stroke Undergoing Mechanical Thrombectomy

Background: Only few studies have investigated the relationship between the histopathology of retrieved thrombi and clinical outcomes. This study aimed to evaluate thrombus composition and its association with clinical, laboratory, and neurointerventional findings in patients treated by mechanical thrombectomy due to acute large vessel occlusion. Methods: At our institution, 79 patients were treated by mechanical thrombectomy using a stent retriever and/or aspiration catheter between August 2015 and August 2016. The retrieved thrombi were quantitatively analyzed to quantify red blood cells, white blood cells, and fibrin by area. We divided the patients into two groups – a fibrin-rich group and an erythrocyte-rich group – based on the predominant composition in the thrombus. The groups were compared for imaging, clinical, and neurointerventional data. Results: The retrieved thrombi from 43 patients with acute stroke from internal carotid artery, middle cerebral artery, or basilar artery occlusion were histologically analyzed. Erythrocyte-rich thrombi were present in 18 cases, while fibrin-rich thrombi were present in 25 cases. A cardioembolic etiology was significantly more prevalent among the patients with fibrin-rich thrombi than among those with erythrocyte-rich thrombi. Attenuation of thrombus density as shown on computed tomography images was greater in patients with erythrocyte-rich thrombi than in those with fibrin-rich thrombi. All other clinical and laboratory characteristics remained the same. Patients with erythrocyte-rich thrombi had a smaller number of recanalization maneuvers, shorter procedure times, a shorter time interval between arrival and recanalization, and a higher percentage of stent retrievers in the final recanalization procedure. The occluded vessels did not differ significantly. Conclusions: In this study, erythrocyte-rich thrombus was associated with noncardioembolic etiology, higher thrombus density, and reduced procedure time

Evaluation of Prolonged Endometrial Inflammation Associated with the Periparturient Metabolic State in Dairy Cows

The objectives of this study were to assess the sequential dynamics of the endometrial polymorphonuclear cells (PMN) after calving by endometrial cytology, and clarify the factors that cause prolonged endometrial inflammation in lactating dairy cows. A total of 33 lactating Holstein dairy cows were used from −4 to 8 wk relative to calving (0 wk: the calving week). Endometrial samples were obtained sequentially from 2 to 8 wk. Body condition score and backfat thickness were obtained weekly from −4 to 8 wk. Blood samples collected from −4 to 8 wk were analyzed for indicators of energy status, hepatic function, systemic inflammation, and calcium. Blood amino acids were measured at 2 wk. Daily milk production was determined between 5 and 65 d postpartum. Based on the sequential cytological analysis, the endometrial inflammation threshold was set at ≥5.0% PMN, and the median wk of PMN% lower than 5.0% was 4.5 wk in this study; therefore, we classified the cows into the early group (cows with endometrial inflammation converged within 4 wk: n = 17) and the late group (cows with endometrial inflammation converged at or after 5 wk: n = 16). There were no differences in daily milk production, energy status, hepatic function, blood calcium concentration, and systemic inflammatory response. The late group had lower body condition scores and backfat thickness during the experimental period, and a higher blood concentration of 3-methyl histidine, indicating muscle breakdown, was observed in the late group at 2 wk. Our findings indicated that the lack of body fat reservation during the peripartum period and the increased muscle breakdown after calving were risk factors for prolonged endometrial inflammation