Effect of sub- and supercritical water treatments on the physicochemical properties of crab shell chitin and its enzymatic degradation

This study examined the effects of sub- and supercritical water pretreatments on the physicochemical properties of crab shell α-chitin and its enzymatic degradation to obtain N,N′-diacetylchitobiose (GlcNAc)2. Following sub- and supercritical water pretreatments, the protein in the crab shell was removed and the residue of crab shell contained α-chitin and CaCO3. Prolonged pretreatment led to α-chitin decomposition. The reaction of pure α-chitin in sub- and supercritical water pretreatments was investigated separately; we observed lower mean molecular weight and weaker hydrogen bonds compared with untreated α-chitin. (GlcNAc)2 yields from enzymatic degradation of subcritical (350 °C, 7 min) and supercritical water (400 °C, 2.5 min) pretreated crab shell were 8% and 6%, compared with 0% without any pretreatment. This study shows that sub- and supercritical water pretreatments of crab shell provide to an alternative method to the use of acid and base for decalcification and deproteinization of crab shell required for (GlcNAc)2 production.ArticleCarbohydrate Polymers. 134:718-725 (2015)journal articl

Effect of LCZ696, a dual angiotensin receptor neprilysin inhibitor, on isoproterenol-induced cardiac hypertrophy, fibrosis, and hemodynamic change in rats

Background: Recent clinical studies have shown that treatment with LCZ696, a complex containing the angiotensin receptor blocker valsartan and neprilysin inhibitor sacubitril, improves the prognosis of heart failure patients with a reduced ejection fraction. This study evaluated whether LCZ696 affects left ventricular hypertrophy, fibrosis, and hemodynamics in isoproterenol (ISO)-treated rats compared with valsartan alone. Methods: Male Wistar rats received subcutaneous saline (n = 10), subcutaneous ISO (2.4 mg/kg/day; n = 10), subcutaneous ISO + oral LCZ696 (60 mg/kg/day; n = 20) (ISO-LCZ), or subcutaneous ISO + oral valsartan (30 mg/kg/day; n = 20) (ISO-VAL) for 7 days. Results: LCZ696 and valsartan did not significantly reduce the increased heart weight/body weight ratio in rats treated with ISO. Echocardiography showed that the deceleration time shortened by ISO was restored by LCZ696 but not valsartan alone (p = 0.01 vs. the ISO group). Histological analysis showed that cardiac interstitial fibrosis increased by ISO was decreased significantly by LCZ696 but not valsartan alone (control: 0.10 ± 0.14%; ISO: 0.41 ± 0.32%; ISO-LCZ: 0.19 ± 0.23% [p < 0.01 vs. the ISO group]; ISO-VAL: 0.34 ± 0.23% [p = 0.34 vs. the ISO group]). Quantitative polymerase chain reaction showed that mRNA expression of Tgfb1, Col1a1, Ccl2, and Anp increased by ISO was significantly attenuated by LCZ696 but not valsartan alone (p < 0.05 vs. the ISO group). Conclusions: LCZ696 improves cardiac fibrosis, but not hypertrophy, caused by continuous exposure to ISO in rats

A case of chorioangioma with polyhydramnios

Chorioangioma is the most common benign placental tumor arising from the chorionic stroma and capillaries, and histologically accounts for about 1% of placental tumors1). It rarely exceeds 5 cm in diameter, and is clinically diagnosed in 1 out of every 8,000-50,000 patients1). We report a patient with a relatively large chorioangioma (10 cm in diameter) accompanied by polyhydramnios

Gamma Band Neural Synchronization Deficits for Auditory Steady State Responses in Bipolar Disorder Patients

Periodic auditory click stimulation has been reported to elicit an auditory steady state response (ASSR). The ASSR has been suggested to reflect the efficiency of γ-amino butyric acid (GABA) inhibitory interneuronal activity. Although a potential role for GABAergic dysfunction has been previously proposed, the role of neural synchronization in the ASSR in people with bipolar disorder (BD) has received little attention. In the current study, we investigated ASSRs to 20 Hz, 30 Hz, 40 Hz and 80 Hz click trains in BD patients. A total of 14 (4 males) BD patients and 25 (10 males) healthy controls participated in this study. ASSRs were obtained using whole-head 306-channel magnetoencephalography to calculate, ASSR power values and phase locking factors (PLF). BD patients exhibited significantly reduced mean ASSR power and PLF values bilaterally at frequencies of 30, 40, and 80 Hz (p<0.05 for these frequencies). At 20 Hz, bipolar patients showed no significant reduction in mean ASSR power and PLF values. There was a significant negative correlation between 80 Hz-ASSR-power values obtained from the right hemisphere and scores on the Hamilton Depression Rating Scale (rho = −0.86, p = 0.0003). The current study showed reduced low and high gamma band ASSR power and PLF bilaterally with no significant beta band ASSR reduction in BD patients. BD patients are characterized by deficits in gamma band oscillations, which may be associated with GABA inhibitory interneuronal activity dysfunction

Combination therapy with pemafibrate (K-877) and pitavastatin improves vascular endothelial dysfunction in dahl/salt-sensitive rats fed a high-salt and high-fat diet

Background Statins suppress the progression of atherosclerosis by reducing low-density lipoprotein (LDL) cholesterol levels. Pemafibrate (K-877), a novel selective peroxisome proliferator-activated receptor alpha modulator, is expected to reduce residual risk factors including high triglycerides (TGs) and low high-density lipoprotein (HDL) cholesterol during statin treatment. However, it is not known if statin therapy with add-on pemafibrate improves the progression of atherosclerosis. The aim of this study was to assess the effect of combination therapy with pitavastatin and pemafibrate on lipid profiles and endothelial dysfunction in hypertension and insulin resistance model rats. Methods Seven-week-old male Dahl salt-sensitive (DS) rats were divided into the following five treatment groups (normal diet (ND) plus vehicle, high-salt and high-fat diet (HD) plus vehicle, HD plus pitavastatin (0.3 mg/kg/day), HD plus pemafibrate (K-877) (0.5 mg/kg/day), and HD plus combination of pitavastatin and pemafibrate) and treated for 12 weeks. At 19 weeks, endothelium-dependent relaxation of the thoracic aorta in response to acetylcholine was evaluated. Results After feeding for 12 weeks, systolic blood pressure and plasma levels of total cholesterol were significantly higher in the HD-vehicle group compared with the ND-vehicle group. Combination therapy with pitavastatin and pemafibrate significantly reduced systolic blood pressure, TG levels, including total, chylomicron (CM), very LDL (VLDL), HDL-TG, and cholesterol levels, including total, CM, VLDL, and LDL-cholesterol, compared with vehicle treatment. Acetylcholine caused concentration-dependent relaxation of thoracic aorta rings that were pre-contracted with phenylephrine in all rats. Relaxation rates in the HD-vehicle group were significantly lower compared with the ND-vehicle group. Relaxation rates in the HD-combination of pitavastatin and pemafibrate group significantly increased compared with the HD-vehicle group, although neither medication alone ameliorated relaxation rates significantly. Western blotting experiments showed increased phosphorylated endothelial nitric oxide synthase protein expression in aortas from rats in the HD-pemafibrate group and the HD-combination group compared with the HD-vehicle group. However, the expression levels did not respond significantly to pitavastatin alone. Conclusions Combination therapy with pitavastatin and pemafibrate improved lipid profiles and endothelial dysfunction in hypertension and insulin resistance model rats. Pemafibrate as an add-on strategy to statins may be useful for preventing atherosclerosis progression

Poly(A)-specific ribonuclease regulates the processing of small-subunit rRNAs in human cells

Ribosome biogenesis occurs successively in the nucleolus, nucleoplasm, and cytoplasm. Maturation of the ribosomal small subunit is completed in the cytoplasm by incorporation of a particular class of ribosomal proteins and final cleavage of 18S-E pre-rRNA (18S-E). Here, we show that poly(A)-specific ribonuclease (PARN) participates in steps leading to 18S-E maturation in human cells. We found PARN as a novel component of the pre-40S particle pulled down with the pre-ribosome factor LTV1 or Bystin. Reverse pull-down analysis revealed that PARN is a constitutive component of the Bystin-associated pre-40S particle. Knockdown of PARN or exogenous expression of an enzyme-dead PARN mutant (D28A) accumulated 18S-E in both the cytoplasm and nucleus. Moreover, expression of D28A accumulated 18S-E in Bystin-associated pre-40S particles, suggesting that the enzymatic activity of PARN is necessary for the release of 18S-E from Bystin-associated pre-40S particles. Finally, RNase H–based fragmentation analysis and 3΄-sequence analysis of 18S-E species present in cells expressing wild-type PARN or D28A suggested that PARN degrades the extended regions encompassing nucleotides 5–44 at the 3΄ end of mature 18S rRNA. Our results reveal a novel role for PARN in ribosome biogenesis in human cells

A case of placenta previa accreta successfully treated by open infrarenal aortic clamping

Open infrarenal aortic clamping has been performed for traumatic pelvic hemorrhage or aortic rupture, and there are few reports of its use in the field of obstetrics and gynecology1). We report a patient with placenta previa accreta who was successfully treated by open infrarenal aortic clamping