A novel ring-like complex of Xenopus proteins essential for the initiation of DNA replication

We have identified Xenopus homologs of the budding yeast Sld5 and its three interacting proteins. These form a novel complex essential for the initiation of DNA replication in Xenopus egg extracts. The complex binds to chromatin in a manner dependent on replication licensing and S-phase CDK. The chromatin binding of the complex and that of Cdc45 are mutually dependent and both bindings require Xenopus Cut5, the yeast homolog of which interacts with Sld5. On replicating chromatin the complex interacts with Cdc45 and MCM, putative components of replication machinery. Electron microscopy further reveals that the complex has a ring-like structure. These results suggest that the complex plays an essential role in the elongation stage of DNA replication as well as the initiation stage

Prenatal and early postnatal NOAEL-dose clothianidin exposure leads to a reduction of germ cells in juvenile male mice

Neonicotinoids are pesticides used worldwide. They bind to insect nicotinic acetylcholine receptors (nAChRs) with high affinity. We previously reported that clothianidin (CTD), one of the latest neonicotinoids, reduced antioxidant expression and induced germ cell death in the adult testis of vertebrates. Here, we investigated the male reproductive toxicity of prenatal and early postnatal exposure to CTD, because it is likely that developmental exposure more severely affects the testis compared to adults due to the absence of the blood-testis barrier. Pregnant C57BL/6 mice were given water gel blended with CTD (0, 10 or 50 mg/kg/day; noobserved- adverse-effect-level [NOAEL for mice]: 47.2 mg/kg/day) between gestational day 1 and 14 days post-partum. We then examined the testes of male offspring at postnatal day 14. The testis weights and the numbers of germ cells per seminiferous tubule were decreased in the CTD-50 group, and abnormal tubules containing no germ cells appeared. Nevertheless, the apoptotic cell number and proliferative activity were not significantly different between the control and CTD-exposed groups. There were no significant differences in the androgen-related parameters, such as the Leydig cell volume per testis, the Sertoli cell number and the tubule diameter. The present study is the first demonstration that in utero and lactational exposures to CTD at around the NOAEL for mice reduce the germ cell number, but our findings suggest that these exposures do not affect steroidogenesis in Leydig cells during prenatal or early postnatal life

Impact of pre-sarcopenia in sorafenib treatment for advanced hepatocellular carcinoma.

BACKGROUND:The present study aimed to investigate the impact of pre-sarcopenia on the prognosis of patients with advanced hepatocellular carcinoma (HCC) treated with sorafenib. METHODS:We enrolled 214 patients (71 ± 10 years old; 166 men and 48 women; 90% Child-Pugh grade A and 10% Child-Pugh grade B) treated with sorafenib in our hospital from July 2009 to August 2016. The muscle volume was measured from CT images just before sorafenib administration using software (SliceOmatic). Skeletal muscle mass index was calculated, and the presence of pre-sarcopenia was judged according to the standard (42 cm2/m2 for men and 38 cm2/m2 for women) proposed by the Japan Society of Hepatology. RESULTS:Pre-sarcopenia was found in 123 patients (57%). The overall survival (OS) in patients with pre-sarcopenia tended to be worse than in patients without pre-sarcopenia (median 252 vs. 284 days, respectively; p = 0.16). Multivariate Cox hazard analysis revealed a baseline serum albumin level of ≤3.5 g/dl [hazard ratio (HR) 1.9; p = 0.0006], a baseline alpha-fetoprotein(AFP) level of ≥100 ng/ml (HR 2.1; p = 0.002), presence of lesions in bilateral hepatic lobes (HR 1.7; p = 0.03), and presence of major portal vein invasion (HR 1.8; p = 0.01) to be independent prognostic factors. In the 68 patients who had three or more negative prognostic factors, the presence of pre-sarcopenia did not correlate with prognosis. Of the 146 patients who had two or less prognostic factors, OS was significantly worse in 84 patients (58%) with pre-sarcopenia than in 62 patients without pre-sarcopenia (median 417 vs. 562 days, respectively; p = 0.047), and Cox hazard analysis revealed pre-sarcopenia to be an important prognostic factor (HR 1.6; p = 0.047). CONCLUSION:In sorafenib treatment for advanced HCC, pre-sarcopenia is a significant prognostic factor in patients with two or less negative prognostic factors, and could be the target of intervention to improve prognosis

Prediction of diuretic response to tolvaptan by a simple, readily available spot urine Na/K ratio.

BACKGROUND:Tolvaptan is vasopressin type 2 receptor antagonist that inhibits water reabsorption. It is used in combination with standard diuretics to treat ascites unresponsive to standard diuretic therapy or hyponatremia because of liver cirrhosis. This study evaluated the effectiveness and safety of tolvaptan in clinical practice and aimed to determine the factors related to its effectiveness. METHODS:Tolvaptan was administered to 88 consecutive cirrhotic patients with ascites unresponsive to standard diuretic therapy. An effective treatment response was a ≥2% reduction in body weight on day 7. The association of patient pretreatment characteristics with therapeutic effects was analyzed. RESULTS:Mean weight reduction on day 7 of tolvaptan therapy was -2.9% ± 3.2%, and treatment was effective in 52% of patients. Multivariate analysis revealed that spot urine Na/K ratio ≥2.5 at baseline was the only factor independently related to therapeutic effect, with an odds ratio of 7.85 (95% confidence interval 2.64-23.40, p = 0.0002). Weight reduction percentage on day 7 was -4.0% ± 2.8% in patients with spot urine Na/K ≥2.5, which was significantly greater than the 0.7% ± 2.7% loss in those with urine Na/K < 2.5 (p < 0.05). A spot urine Na/K ratio ≥2.5 had a sensitivity of 85% and specificity of 60% for predicting effective treatment. No adverse events of treatment led to treatment discontinuation. CONCLUSIONS:Baseline spot urine Na/K was predictive of an effective response to tolvaptan therapy. It is simple to perform and readily available and might serve as an indicator of optimal timing of tolvaptan administration in patients with inadequate response to conventional Na diuretic therapy