Liver regeneration following partial hepatectomy is improved by enhancing the HGF/Met axis and Akt and Erk pathways after low-power laser irradiation in rats

A simple, easy, and safe procedure aiming to improve liver regeneration could be of great clinical benefit in critical situations such as major hepatectomy, trauma, or hemorrhage. Low-power laser irradiation (LPLI) has come into a wide range of use in clinical practice by inducing regeneration in healthy and injured tissues. However, the effect of LPLI on the process of liver regeneration, especially those related to the molecular mechanisms, is not fully understood. Thus, the aim of the present study was to investigate the main molecular mechanisms involved in liver regeneration of partially hepatectomized rats exposed to LPLI. We used Wistar male rats, which had their remaining liver irradiated or not with LPLI (wavelength of 632.8 nm and fluence of 65 mW/cm²) for 15 min after a 70 % hepatectomy. We subsequently investigated hepatocyte growth factor (HGF), Met, Akt, and Erk 1/2 signaling pathways through protein expression and phosphorylation analyses along with cell proliferation (proliferating cell nuclear antigen (PCNA) and Ki-67) using immunoblotting and histological studies. Our results show that LPLI can improve liver regeneration as shown by increased HGF protein expression and the phosphorylation levels of Met, Akt, and Erk 1/2 accompanied by higher levels of the PCNA and Ki-67 protein in the remnant livers. In summary, our results suggest that LPLI may play a clinical role as a simple, fast, and easy-to-perform strategy in order to enhance the liver regenerative capacity of a small liver remnant after hepatectomy.     

Relaxin levels in ovum donation pregnancies

STUDY OBJECTIVE: To investigate the relative contributions of the corpus luteum (CL) and the placenta to the circulating levels of relaxin during pregnancy. PATIENTS: Forty-one patients in whom pregnancy had been achieved by ovum donation. RESULTS: Relaxin was not detected in the serum of 36 patients; in the remaining 5, although it was detectable, the levels were markedly reduced when compared with those in normal pregnancies. CONCLUSION: These results demonstrate that the CL is essential for the maintenance of normal circulating levels of relaxin during pregnancy.     

The effect of the dose of human chorionic gonadotropin and the type of gonadotropin stimulation on oocyte recovery rates in an in vitro fertilization program

The effect of the dose of human chorionic gonadotropin (hCG) on oocyte retrieval in an in vitro fertilization (IVF) program was studied. Following ovulation induction using clomiphene citrate and either pure follicle-stimulating hormone (FSH) or human menopausal gonadotropin (hMG), hCG was administered at a dose of 2000 IU (n = 88), 5000 IU (n = 110), and 10,000 IU (n = 104). There was a significantly lower successful oocyte recovery in patients who received 2000 IU of hCG (77.3%) compared with patients who received either 5000 IU of hCG (95.5%) or 10,000 IU of hCG (98.1%; P less than 0.001). There was no significant difference between 5000 or 10,000 IU of hCG. In patients who received 2000 IU of hCG, successful oocyte recovery was significantly lower when pure FSH was used (60%) compared with those who received hMG (84.1%; P less than 0.03). Patients have different thresholds for follicular response to hCG and the recommended minimum dose of hCG should be at least 5000 IU.     

Transesophageal echocardiographic identification of right vertebral artery

We describe a transesophageal technique for identifying the origin and precervical course of the right vertebral artery with the probe positioned in the upper esophagus. The technique was successful in 9 of 11 patients in whom it was attempted.     

Extended hepatectomy in patients with hepatobiliary malignancies with and without preoperative portal vein embolization

HYPOTHESIS: Preoperative portal vein embolization (PVE) allows potentially curative hepatic resection without additional morbidity or mortality in patients with hepatobiliary malignancies who are marginal candidates for resection based on small liver remnant size. DESIGN: A retrospective review of a consecutive series of patients in a multi-institutional database who underwent extended hepatectomy. SETTING: University-based referral centers. PATIENTS: Forty-two patients underwent preoperative determination of the future liver remnant (FLR) volume before extended hepatectomy (> or = 5 segments) for hepatobiliary malignancy without chronic underlying liver disease. Patients were stratified by treatment with or without preoperative PVE. INTERVENTION: Preoperative percutaneous PVE. MAIN OUTCOME MEASURES: Clinical characteristics, FLR volume, operative morbidity, and survival. RESULTS: There was no difference between the groups that did and did not undergo PVE for the number of tumors, tumor size, estimated blood loss, duration of the operation, complexity of resection, or surgical margins. The FLR at presentation was significantly smaller in patients who underwent PVE than in patients who did not undergo PVE (18% vs 23%; P<.001). After PVE, FLR volumes increased significantly (P =.003); preoperative FLR volumes were similar in both groups (patients who underwent PVE, 25%; and patients who did not undergo PVE, 23%). There was no perioperative mortality and no statistical difference in the incidence of perioperative complications between those who did and those who did not undergo PVE (5 [28%] of 18 patients vs 5 [21%] of 24 patients). The overall 3-year survival was 65% and the median survival duration was equivalent in the 2 groups (40 vs 52 months for those who did vs those who did not undergo PVE). CONCLUSION: Portal vein embolization enables safe and potentially curative extended hepatectomy in a subset of patients who would otherwise be marginal candidates for resection based on a small liver remnant size.     

Statistical analysis of historical occupational dose records at a large medical center

Routine monitoring of occupational radiation exposure is done primarily to demonstrate compliance with dose limits. Statistical analysis of past and present dose records provides a useful tool in the management of institutional radiation safety programs. In this study, a statistical analysis of annual dose records from 1985-1999 from a large tertiary care medical center with a cyclotron and radiopharmaceutical production facility is performed. A total of 6,089 annual dose records, categorized into ten occupational groups, were included in the analysis. Dose distribution is skewed, with 85% of workers receiving an annual dose of less than 1.0 mSv, while 1.3% have doses > or =10 mSv. The mean annual dose of all monitored workers during this 15-y period ranged from 0.5 to 1.2 mSv. Large variation in the mean annual dose exists among the different occupational groups. Four occupational groups were identified as relatively highly exposed, namely cyclotron and radiopharmaceutical production, cardiac catheterization, nuclear medicine, and diagnostic radiology. These four occupational groups also showed different trends in the mean annual dose. A correlation study showed that total annual collective dose has no linear association with the number of monitored workers, the number of measurably exposed workers, or the number of workers with annual dose between 0.1 to <10 mSv. Moderate correlation (r = 0.64) was observed between the annual collective dose and the collective dose of workers with an annual dose between 0.1 to <10 mSv. A strong and significant correlation (r = 0.95) exists between the total annual collective dose and both the number of workers with annual dose of > or =10 mSv and the corresponding collective dose due to these highly exposed workers. Although the fraction of these highly exposed workers is small (about 1%), they have a significant impact on the total collective dose and their contribution can be as high as 50%. Workers with annual dose of > or =10 mSv tend to concentrate in a few identified occupational groups and not across all occupational groupings. The cyclotron and radiopharmaceutical production department is of particular concern due to its high individual dose levels and increasing mean annual dose trend for the last 5 y. Radiochemists and cyclotron engineers tend to receive an annual dose exceeding the dose limit. A plot of the collective dose of highly exposed workers vs. the total collective dose shows that if a dose constraint of 10 mSv is imposed on highly exposed occupational groups, the total collective dose is expected to be about 200 person-mSv.     

Synthesis and anticancer and anti-HIV testing of some pyrazino[1,2-a]benzimidazole derivatives

In this study, some 1-methylene-2,3-diaryl-1,2-dihydropyrazino[1,2-a]benzimidazole and some 1-(2-arylvinyl)-3-arylpyrazino[1,2-a]benzimidazole derivatives were synthesised. The structure elucidation of the compounds was performed by IR, 1H-NMR and MASS spectroscopic data and elemental analyses results. Anticancer and anti-HIV activities of the compounds were examined, however no anti-HIV activity was seen; highly notable anticancer activity was obtained. It was also observed that the compounds were more potent against leukaemia cell lines.