Determination of catechins in cosmetics by high⁃performance liquid chromatography / 上海预防医学

ObjectiveTo establish a high⁃performance liquid chromatography （HPLC） quantitative method for the determination of epicatechin （EC）， （-）⁃epicatechin gallate （ECG）， （-）⁃epigallocatechin （EGC）， （-）⁃epigallocatechin gallate （EGCG）， （-）⁃gallocatechin （GC）， （-）⁃gallocatechin gallate （GCG）， （-）⁃catechin gallate （CG）， cianidanol （CD） and gallic acid （GA） in cosmetics. MethodsSamples were prepared by ultrasonic extraction and followed by high-speed centrifugation of the extraction solution. The supernatant was filtered by 0.45 μm Millipore filter. The continued filtrate was taken for analysis. A reversed phase column， Kromasil 100-5 C18 （5 μm， 4.6 mm×250 mm） was used with 0.05% trifluoroacetic acid buffer and methanol as mobile phase under the condition of gradient elution. Diode array detection （DAD） method was used for the determination. Qualitative and quantitative determination was conducted in 10 batches of commercially available cosmetics. ResultsThe relative standard deviations （RSD） were in the range of 0.11%-6.30% （n=3）； the recoveries were in the range of 84.4%-114.7%. The method showed a good linearity within the concentration range of 0.49-105.39 mg·L-1 （r>0.995）. The detection limit was 5 μg·g-1. In 10 batches of commercially available cosmetics， three batches showed positive result， which was consistent with the UV spectrum of the standard. ConclusionThis method is efficient， sensitive and accurate. It is applicable to the determination of EC， ECG， EGC， EGCG， GC， GCG， CG， CD and GA in cosmetics.

Cryptosporidium spp., Giardia intestinalis, and Enterocytozoon bieneusi in Captive Non-Human Primates in Qinling Mountains

Non-human primates (NHPs) are confirmed as reservoirs of Cryptosporidium spp., Giardia intestinalis, and Enterocytozoon bieneusi. In this study, 197 fresh fecal samples from 8 NHP species in Qinling Mountains, northwestern China, were collected and examined using multilocus sequence typing (MLST) method. The results showed that 35 (17.8%) samples were positive for tested parasites, including Cryptosporidium spp. (3.0%), G. intestinalis (2.0%), and E. bieneusi (12.7%). Cryptosporidium spp. were detected in 6 fecal samples of Macaca mulatta, and were identified as C. parvum (n=1) and C. andersoni (n=5). Subtyping analysis showed Cryptosporidium spp. belonged to the C. andersoni MLST subtype (A4, A4, A4, and A1) and C. parvum 60 kDa glycoprotein (gp60) subtype IId A15G2R1. G. intestinalis assemblage E was detected in 3 M. mulatta and 1 Saimiri sciureus. Intra-variations were observed at the triose phosphate isomerase (tpi), beta giardin (bg), and glutamate dehydrogenase (gdh) loci, with 3, 1, and 2 new subtypes found in respective locus. E. bieneusi was found in Cercopithecus neglectus (25.0%), Papio hamadrayas (16.7%), M. mulatta (16.3%), S. sciureus (10%), and Rhinopithecus roxellana (9.5%), with 5 ribosomal internal transcribed spacer (ITS) genotypes: 2 known genotypes (D and BEB6) and 3 novel genotypes (MH, XH, and BSH). These findings indicated the presence of zoonotic potential of Cryptosporidium spp. and E. bieneusi in NHPs in Qinling Mountains. This is the first report of C. andersoni in NHPs. The present study provided basic information for control of cryptosporidiosis, giardiasis, and microsporidiosis in human and animals in this area.

Familiar hypertrophic cardiomyopathy caused by a IVS15-1G > A mutation in cardiac myosin-binding protein C gene / 中华心血管病杂志

<p><b>OBJECTIVE</b>To detect the disease-causing gene mutation of hypertrophic cardiomyopathy (HCM) in a Chinese family and to analyze the correlation of the genotype and the phenotype.</p><p><b>METHODS</b>One family affected with HCM was studied. The clinical data including symptom, physical examination, echocardiography and electrocardiography were collected. The full encoding exons and flanking sequences of beta-myosin heavy chain gene (MYH7) and cardiac myosin-binding protein C gene (MYBPC3) were amplified with PCR and the products were sequenced.</p><p><b>RESULTS</b>A G8887A mutation, which is an acceptor splicing site of intron 15 (IVS15-1G > A) in MYBPC3 (gi: Y10129) was identified in 6 out of 11 family members. Three mutation carriers developed HCM at 48 - 75 years old with mild chest pain, chest distress and asymmetric septal hypertrophy (13 - 14 mm) and remaining mutation carriers are free of HCM. No mutation was identified in MYH7 gene.</p><p><b>CONCLUSION</b>HCM caused by the IVS15-1G > A mutation is a benign phenotype. It is helpful to screen MYBPC3 gene mutation in late-onset HCM patients with mild symptoms.</p>

Centrifugal force stretcher a new of in vitro mechanical cell stimulator / 生理学报

A number of mechanical cell stimulators have been used to study the effect of mechanical stimulation on cells in vitro. But the efficiency of these devices is not fully desirable. We recently developed a new device for mechanical cell stimulation, the centrifugal force stretcher, and compared its efficacy with that of the traditional Flexercell Strain Unit. When the mechanical stretcher circumrotates with certain speed, cardiac myocytes attached on the plate are stretched and elongated by centrifugal force. Neonatal rat cardiac myocytes were isolated by enzymatic dissociation from the hearts of 3~5 d old Sprague Dawley rats, and were mechanically stimulated by traditional 20% stretch and 180 r/min centrifugal force for 12 and 24 h. The effects of mechanical stimulation on the hypertrophic response of neonatal rat cardiac myocytes and production of angiotensin II (Ang II) were examined. Compared with the non-stretch group, the radioactivity of (3)H-leucine incorporated into the stretch-stimulated cardiac myocytes in the centrifugal force stretch group was significantly higher [(1295.17+/-51.19) vs (1122.67+/-51.63) in 12 h; (1447.5+/-35.96) vs (1210.67+/-90.92) in 24 h, P<0.05]. Ang II was also dramatically increased by 128% in 12 h (P<0.05) and 139% in 24 h (P<0.01). After the myocytes was stretched for 24 h, the LDH level in the medium in the Flexercell Strain Unit group was significantly higher than that in the centrifugal force group [(14.5+/-8.7) U/L vs (7.8+/-4.3) U/L, P<0.05]. The centrifugal force stretcher is a new and improved mechanical cell stimulator with the same effects on the protein synthesis and Ang II secretion of the cardiac myocytes, and the damage to the cells bronght by this stimulator is relatively slighter in comparison with the Flexercell Strain Unit.