Primary culture of fetalrat liver bipotential progenitor cells

Summary Techniques are described for the rapid isolation, monolayer culture, and phenotypical characterization of embryonic Day 12 (E12) rat liver epithelial cells. In vitro assays of the differentiation potential of these cells are currently being performed under conditions that make use of-modified Eagle's medium supplemented with fetal bovine serum, insulin, and dexamethasone with or without sodium butyrate. In the absence of sodium butyrate, the cells differentiate along the hepatocytic cell lineage, whereas in its presence they express the phenotype of the biliary ductal epithelial cell lineage.     

Anti-soluble liver antigen (SLA) antibodies in chronic HCV infection

Hepatitis C infection is associated with autoimmune disorders, such as the production of autoantibodies. Anti-LKM1 and anti-LC1, immunomarkers of type 2 autoimmune hepatitis, have been previously associated with a HCV infection. Anti-Soluble-Liver-Antigen autoantibodies (SLA) are specifically associated with type 1 and type 2 autoimmune hepatitis and more closely related to patients who relapse after steroid therapy. The recent molecular cloning of the soluble liver antigen provides the opportunity to develop more specific tests for the detection of antibodies against it. The aim of this work is to characterize anti-soluble-liver autoantibodies in sera from patients chronically infected by HCV. A recombinant cDNA from activated Jurkat cells coding for the full length tRNP(Ser)Sec/SLA antigen was obtained. ELISA, Western Blot and immunoprecipitation tests were developed and used to search for linear and conformational epitopes recognized by anti-SLA antibodies in sera from patients chronically infected by HCV. Anti-soluble liver antigen antibodies were found in sera from 10.4% of HCV-infected patients. The prevalence was significantly increased to 27% when anti-LKM1 was also present. Most anti-SLA reactivity was directed against conformational epitopes on the antigen. The means titers by ELISA were lower than those obtained in type 2 AIH. The result of autoantibody isotyping showed a subclass restriction to IgG1 and also IgG4. This study shows the presence of anti-SLA antibodies in approximately 10% of HCV infected patients. The prevalence of SLA autoantibodies in HCV infected patients increases when LKM1 autoantibodies are also present. The relationship between the prevalence of this characteristic autoimmune hepatitis autoantibody and the implication of an autoimmune phenomenon in the liver injury of patients chronically infected by HCV needs further investigation.     

Cell growth recovery after treatments at various supraoptimal temperatures.

The growth recovery kinetics of HeLa cells was investigated after treatments at intermediate (43-45 degrees) or high (49-55 degrees) supraoptimal temperatures for various periods of time (2 to 300 min) or after irradiations with nanosecond infrared CO2-laser pulses at energy densities equivalent to very high temperatures rises. After treatments at intermediate temperatures, single cells developed into colonies smaller than those obtained from nonheated control cells. Daily incorporations of pulsed [3H]thymidine in whole populations and microscopic observations of individual cell proliferation revealed a complex growth recovery for both survivors and dying cells. In contrast, colonies arising from cells treated at temperatures above 49 degrees do not differ in size from those developed from controls, and growth evaluations by [3H]thymidine and microscopy demonstrated that survivors resume normal proliferation immediately after treatments. The results which are supported by other studies on the effects of dose fractionation and metabolism status on cell survival are further discussed in relation to the "multistep" kinetic model for the cell response to hyperthermia.     

The ability of des-Arg9-bradykinin to relax rabbit isolated mesenteric arteries is acquired during in vitro incubation

Strips of rabbit mesenteric arteries precontracted with phenylephrine relaxed when exposed to des-Arg9-bradykinin (BK), a typical B1 receptor agonist. We showed that the ability of des-Arg9-BK to relax this preparation was acquired during in vitro incubation and was abolished by cycloheximide treatment. In this preparation intimal damage reduced but did not abolish the relaxant effect of des-Arg9-BK, and indomethacin uncovered a contractile effect of des-Arg9-BK also acquired during the in vitro incubation.     

Anti-Soluble Liver Antigen (SLA) Antibodies in Chronic HCV Infection

Hepatitis C infection is associated with autoimmune disorders, such as the production of autoantibodies. Anti-LKM1 and anti-LC1, immunomarkers of type 2 autoimmune hepatitis, have been previously associated with a HCV infection. Anti-Soluble-Liver-Antigen autoantibodies (SLA) are specifically associated with type 1 and type 2 autoimmune hepatitis and more closely related to patients who relapse after steroid therapy. The recent molecular cloning of the soluble liver antigen provides the opportunity to develop more specific tests for the detection of antibodies against it. The aim of this work is to characterize anti-soluble-liver autoantibodies in sera from patients chronically infected by HCV. A recombinant cDNA from activated Jurkat cells coding for the full length tRNP^(Ser)Sec/SLA antigen was obtained. ELISA, Western Blot and immunoprecipitation tests were developed and used to search for linear and conformational epitopes recognized by anti-SLA antibodies in sera from patients chronically infected by HCV. Anti-soluble liver antigen antibodies were found in sera from 10.4% of HCV-infected patients. The prevalence was significantly increased to 27% when anti-LKM1 was also present. Most anti-SLA reactivity was directed against conformational epitopes on the antigen. The means titers by ELISA were lower than those obtained in type 2 AIH. The result of autoantibody isotyping showed a subclass restriction to IgG1 and also IgG4. This study shows the presence of anti-SLA antibodies in approximately 10% of HCV infected patients. The prevalence of SLA autoantibodies in HCV infected patients increases when LKM1 autoantibodies are also present. The relationship between the prevalence of this characteristic autoimmune hepatitis autoantibody and the implication of an autoimmune phenomenon in the liver injury of patients chronically infected by HCV needs further investigation.     

Effects of surgically induced weight loss by Roux-en-Y gastric bypass on osteocalcin

BackgroundOsteocalcin (OC), a protein synthesized by osteoblasts, is a marker of bone turnover with undercarboxylated OC (ucOC) being involved in glucose homeostasis. Although laparoscopic Roux-en-Y gastric bypass (LRYGB)-induced weight loss likely alters bone turnover, data on markers of bone turnover remain less clear. The aim of this study was to examine the effect of surgically induced weight loss on OC and ucOC.MethodsA total of 32 individuals with a body mass index 50.2±10.2 kg/m² underwent LRYGB. Osteocalcin, ucOC, other blood analytes (e.g., vitamin D, leptin, total and high-molecular-weight adiponectin), and homeostasis model assessment for insulin resistance were measured before and after weight loss. The effect of an acute nutrient load on OC parameters after a mixed meal tolerance test also was assessed.ResultsSix months after surgery, there was an increase in OC (17.8±7.4 [mean±SD] [baseline] versus 31.5±9.8 ng/mL [follow-up]; P<.001) and ucOC (7.3±6.2 versus 18.5±8.9 ng/mL; P<.001). Although adiponectin increased, only the magnitude of change in OC and leptin was correlated (r =?.43; P = .017). After weight loss, an acute nutrient load reduced OC (31.5±9.8 [0-hour] versus 29.6±8.2 [2-hour] ng/mL; P = .024), whereas ucOC was higher (18.8±9.3 [0-hour] versus 21.1±8.6 [2-hour] ng/mL; P< .001).ConclusionSurgically induced weight loss was associated with increases in OC and ucOC. Underlying mechanisms are unclear, but change in OC may be related to change in leptin. After a nutrient load, the increase in ucOC suggests a potential role as a short-term compensatory regulator of glucose homeostasis.     

Is There a Role for Visceral Adiposity in Inducing Type 2 Diabetes Remission in Severely Obese Patients Following Biliopancreatic Diversion with Duodenal Switch Surgery?

Background

Severe obesity is often characterized by ectopic fat deposition, which is related to development of type 2 diabetes (T2D). Thus, resolution of T2D may not be linearly associated with weight loss. The importance of ectopic fat reduction after bariatric surgery and T2D resolution is uncertain.

Objective

The aim of this pilot study is to compare body composition and body fat distribution in severely obese patients with or without T2D after biliopancreatic diversion with duodenal switch (BPD-DS) surgery in relation to diabetes resolution.

Methods

Sixty-two severely obese patients were evaluated at baseline, 6, and 12 months. Of these, 40 patients underwent BPD-DS surgery. Anthropometric measurements and abdominal and mid-thigh computed tomography scans were performed at each visit.

Results

Before BPD-DS surgery, obese patients with T2D had higher weight as well as greater ectopic fat deposition in the abdomen and mid-thigh level than obese patients without T2D (p?<?0.05). Resolution of T2D was 65 and 90 % at 6 and 12 months, respectively. No difference in body composition changes at 6 and 12 months could be found between patients without T2D, patients with T2D resolution, and patients who remained T2D. Resolution of T2D was associated with a greater absolute loss of visceral adipose tissue (VAT) in comparison to patients without T2D (?1175?±?570 cm³ vs. ?729?±?394 cm³ at 6 months and ?1647?±?816 cm³ vs. ?1103?±?422 cm³ at 12 months; all p?≤?0.05).

Conclusion

Ectopic fat mobilization, particularly the absolute loss of VAT, may play a major role in T2D resolution following BPD-DS surgery, regardless of the amount of weight loss.