Role of KATPChannels in the Regulation of Rat Dura and Pia Artery Diameter

The aim of the present study was to examine the effect of KATPchannel openers pinacidil and levcromakalim on rat dural and pial arteries as well as their inhibition by glibenclamide. We used an in-vivo genuine closed cranial window model and an in-vitro organ bath. Glibenclamide alone reduced the dural but not the pial artery diameter compared with controls. Intravenous pinacidil and levcro-makalim induced dural and pial artery dilation that was significantly attenuated by glibenclamide. In the organ bath pinacidil and levcromakalim induced dural and middle cerebral artery relaxation that was significantly attenuated by glibenclamide. In conclusion, KATPchannel openers induce increasing diameter/relaxation of dural and pial arteries after intravenous infusion in vivo and on isolated arteries in vitro. Furthermore, dural arteries were more sensitive to KATPchannel openers than pial arteries.

Clinical Course of acute-on-chronic liver failure syndrome and effects on prognosis

Acute-on-chronic liver failure (ACLF) is characterized by acute decompensation (AD) of cirrhosis, organ failure(s), and high 28-day mortality. We investigated whether assessments of patients at specific time points predicted their need for liver transplantation (LT) or the potential futility of their care. We assessed clinical courses of 388 patients who had ACLF at enrollment, from February through September 2011, or during early (28-day) follow-up of the prospective multicenter European Chronic Liver Failure (CLIF) ACLF in Cirrhosis study. We assessed ACLF grades at different time points to define disease resolution, improvement, worsening, or steady or fluctuating course. ACLF resolved or improved in 49.2%, had a steady or fluctuating course in 30.4%, and worsened in 20.4%. The 28-day transplant-free mortality was low-to-moderate (6%-18%) in patients with nonsevere early course (final no ACLF or ACLF-1) and high-to-very high (42%-92%) in those with severe early course (final ACLF-2 or -3) independently of initial grades. Independent predictors of course severity were CLIF Consortium ACLF score (CLIF-C ACLFs) and presence of liver failure (total bilirubin ≥12 mg/dL) at ACLF diagnosis. Eighty-one percent had their final ACLF grade at 1 week, resulting in accurate prediction of short- (28-day) and mid-term (90-day) mortality by ACLF grade at 3-7 days. Among patients that underwent early LT, 75% survived for at least 1 year. Among patients with ≥4 organ failures, or CLIF-C ACLFs >64 at days 3-7 days, and did not undergo LT, mortality was 100% by 28 days.

CONCLUSIONS

Assessment of ACLF patients at 3-7 days of the syndrome provides a tool to define the emergency of LT and a rational basis for intensive care discontinuation owing to futility.

The incidence and morphological features of pyramidal lobe on thyroid ultrasound

The aim of this article is to document the incidence and appearances of the pyramidal lobe of the thyroid gland, and discuss the clinical relevance of this entity in sonographic practice. A prospective study was undertaken over a period of 10 months. A total of 416 consecutive patients attending head and neck ultrasound lists were scanned by a single experienced radiologist or an advanced practitioner sonographer. At the time of reporting, the presence of a pyramidal lobe was recorded. The anatomical morphology was classified into five subgroups devised for the purposes of the study. Appearances were documented in both normal and pathological glands. Of the total number of patients scanned, 90 patients were found to have pyramidal lobes, giving an overall incidence of 21%. In all, 51% were found to originate from the right of the isthmus, 46% from the left and 2% from the midline. One patient had two pyramidal lobes. A significant number of patients having routine neck ultrasounds have an incidental finding of a pyramidal lobe. Ultrasound is an effective modality for the demonstration and classification of the pyramidal lobe, as well as identification of pathology. It is important for radiologists to be aware of this normal variation, as it may be the site of primary or recurrent thyroid pathology. Radiologists should report it where relevant to ensure adequate surgical treatment of pathological glands.

Soluble CD163, a marker of Kupffer cell activation, is related to portal hypertension in patients with liver cirrhosis

BACKGROUND

Activation of Kupffer cells may be involved in the pathogenesis of portal hypertension by release of vasoconstrictive substances and fibrosis due to co-activation of hepatic stellate cells.

AIM

To study soluble plasma (s) CD163, a specific marker of activated macrophages, as a biomarker for portal hypertension in patients with liver cirrhosis.

METHODS

We measured sCD163 concentration and the hepatic venous pressure gradient (HVPG) by liver vein catheterisation in 81 cirrhosis patients (Child-Pugh CP-A: n = 26, CP-B: n = 29, CP-C: n = 26) and 22 healthy subjects. We also measured their cardiac output (CO), cardiac index and systemic vascular resistance (SVR). Liver status was examined by Child-Pugh and MELD-score.

RESULTS

In cirrhosis, sCD163 concentration was nearly three times higher than in controls (4.7 ± 2.5 vs. 1.6 ± 0.5 mg/L, P < 0.001). sCD163 was also higher, as measured in steps by CP-score (P < 0.001). The HVPG rose steeply to an asymptote of 22 mmHg with sCD163 up to about 5 mg/L and not to higher values with higher sCD163. In a multivariate analysis, sCD163 was the only independent predictor of the HVPG but did not predict any of the systemic circulatory findings. sCD163 > 3.95 mg/L (upper normal limit) predicted HVPG ≥ 10 mmHg with a positive predictive value of 0.99.

CONCLUSIONS

Circulating sCD163 originating from activated Kupffer cells is increased in cirrhosis with increasing Child-Pugh score and with increasing HVPG, and it is an independent predictor for HVPG. These findings support a primary role of macrophage activation in portal hypertension, and may indicate a target for biological intervention.

183 EXERCISE INFLUENCES EMBRYO QUALITY IN MARES

Athletic mares are commonly utilized in an embryo transfer regimen during the breeding season, which allows owners to continue to train and compete with these animals. Exercising mares in a hot and humid environment has proven detrimental to embryo recovery rates. However, the effects of exercise under milder temperatures have not been examined. Our goal was to compare embryo recovery rates and embryo quality scores of mares under mild environmental conditions of 2 differing exercise regimens v. a single control group (n = 5). One treatment group (full exercise) consisted of mares (n = 5) exercised 6 days a week throughout the duration of the project. The partial-exercise group (n = 5) was exercised throughout the duration of the project 7 days a week, with full rest from day of detected ovulation to the proceeding embryo collection attempt. This was to limit any deleterious effects exercise may potentially have on the mare and subsequent early developing equine embryo. Exercise resumed the day after an embryo collection attempt for the partial-exercise group. Exercised mares were given a 1-month training period prior to the beginning of this project and were moderately exercised for 30 min in a mechanical exercise pen (free exerciser). Control mares were managed similarly as the other groups, however were not exercised. Mares were bred via artificial insemination and embryos were nonsurgically collected 7 d post-ovulation. Mean environmental temperature during the duration of this study was 27.1°C with average 60% humidity. Immediately following completion of exercise, mares in the full exercise group had a mean temperature increase of 1.0°C and partial-exercised mares increased 0.9°C. Exercise had a significant effect on embryo quality (P < 0.05, Table 1) but did not influence embryo recovery rate. The mean embryo quality score for the control group was 1.1, whereas the full-exercised group was 1.85 and partial-exercised group was 2.5. It appears from these data that exercise has a negative effect on embryo quality, thus lowering the availability of transferable embryos. Embryos of lower quality (≥3) have been shown to result in poor pregnancy rates in horses. Additionally, rest from ovulation to an embryo collection attempt did not improve embryo quality. Table 1.Embryo recovery rate and quality score of embryos from control and exercised mares

Organization and expression of the gene encoding an immunodominant repetitive antigen associated to the cytoskeleton of Trypanosoma cruzi

We have studied the genomic organization and expression of the gene encoding a high molecular mass (300 kDa) repetitive antigen associated with the cytoskeleton of Trypanosoma cruzi. Protease digestion of the native protein, restriction analysis of genomic DNA and sequencing of genomic and cDNA clones indicated that most of the protein is built up by tandemly arranged, nearly identical repeats of 68 amino acids. The gene size was estimated to be approx. 9.4 kb based on the sizes of the transcript and the native protein. The nucleotide sequence conservation among the repeats indicates that selective sequence homogenization, presumably through gene conversion, maintained the amino-acid sequence conservation. Two duplicated allelic forms of this gene were mapped in fragments of about 20 kb. In some strains an additional allele was located in a fragment of 9.4 kb. Our results suggest that this repetitive antigen is a structural protein which could be involved in the attachment of the flagellum to the cell body.