Biological mass spectrometry has been developed for the largE-scale protein identification. The successful identification of protein in proteomic study is based on an effective match of MS data to the sequence in database. Because of the diversity and heterogeneity of protein modification, the experimental data obtained by mass spectrometry does not match the theoretical value sometimes, which makes about 90 percent or more of the tandem mass spectra not be effectively identified. This has become one of the most important technique issues to be resolved in current proteome research. The N-terminal cyclization of peptides, as one of a variety of modification introduced in sample preparation, has been preliminarily studied in this work. The result showed that N-terminal cyclization occurred at the most of the glutamine(Q) or carbamoylmethyl-cysteine(CAM_C) residues and the reaction is often incomplete or partial, both types of peptides could often exist in its respective state at the same time, and the behavior of modified peptides in revered phase chromatography is also changed. The success rate of protein identification could be obviously improved if adding the N-terminal cyclization modification in the database searching. These results will be very helpful in the mass spectrometric data analysis of proteomic study.

Due to the complexity of proteome samples, comprehensive analysis to characterize all proteins was still not possible with present methodologies. It has been shown that replicate runs could increase the number of identified) proteins. However, the redundancy of protein identifications was high. High-abundant peptides tended to be analyzed repeatedly in different runs. To reduce the redundancy and improve the efficiency of identification), we studied the MS/MS acquisition method of linear ion trap Fourier transform ion cyclotron resonance)-mass spectrometry(LTQ-FT) and an acquisition strategy based on exclusion of precursor ions was developed). It proved that the strategy could extremely reduce the redundancy of MS/MS acquisition and improve) the efficiency of protein identifications.

Background Nitrosamines (NAms) are highly carcinogenic and frequently detected in drinking water systems in China, indicating potential human health risk through drinking water. Objective To analyze the distribution of NAms in drinking water in Shanghai and to evaluate relevant human health risk. Methods A total of 94 samples of source water and 120 samples of finished water were collected in February (dry period) and August (wet period) of 2021 from 30 drinking water plants in Shanghai, and eight NAms were quantitatively analyzed by gas chromatography tandem mass spectrometry after solid phase extraction. Cancer risks for different age groups caused by NAms exposure through water were evaluated using Monte Carlo probabilistic method and carcinogens risk assessment model recommended by the United States Environmental Protection Agency. Results The concentrations of total NAms in source and finished water were 12.56-65.86 ng·L⁻¹ and 8.52-57.38 ng·L⁻¹, respectively. The average concentration of total NAms was higher in source water (33.50 ng·L⁻¹) than in finished water (22.07 ng·L⁻¹, P<0.05) during dry season, and lower in source water (16.90 ng·L⁻¹) than in finished water (21.02 ng·L⁻¹, P<0.05) during wet season. The average concentration of total NAms in source water during dry season was twice of that during wet season. The positive rate of N-nitrosodimethylamine (NDMA) was the highest (100%) among the eight NAms. The cancer risk of exposure to NAms in finished water in Shanghai was mainly from the ingestion route, which was mostly caused by NDMA. The cancer risk from exposure to NAms in water for children (median=4.32×10⁻⁵) was slightly higher than that for adults (median=3.34×10⁻⁵) and adolescents (median=2.27×10⁻⁵). The cancer risks of exposure to NAms in water for people of different ages were mainly (80% - 95%) at an acceptable level (1×10⁻⁶ - 1×10⁻⁴). Conclusion NAms contamination is positive in Shanghai’s drinking water and NDMA is the main contaminant. The removal of NAms in water by current water treatment process is season-dependent. The cancer risk of children exposed to NAms in water was slightly higher than that of adults and adolescents, but all at acceptable levels.

Vascular dementia (VaD) subtypes include multi-infarct dementia, subcortical ischemic vascular dementia, strategic-infarct dementia, etc. Poststroke dementia may be related to preexisting cognitive level, and the frequency increased with aging, lower educational level and accompanied vascular risk factors. Vascular cognitive impairment (VCI) forms a spectrum that includes VaD, mixed Alzheimer's disease (AD) with a vascular component, and VCI without dementia. The concept of VCI will improve the early diagnoses and secondary prevention and treatment of VaD, and promote the further research on vascular component in neurodegenrative disorders.
Cognition ; Cognition Disorders ; classification ; diagnosis ; etiology ; Dementia, Multi-Infarct ; classification ; diagnosis ; Dementia, Vascular ; classification ; diagnosis ; Humans

Objective: To analyze the association between different sleep behaviors and overweight and obesity of junior high school students in Yangzhou City, and to provide a basis for policies and interventions related to adolescent health management. Methods: A total of 1 589 students in grades 7-9 from two middle schools in Yangzhou City were selected using the cluster sampling method and were administered with sleep time, bedtime, social jetlag difference, and sleep habits. Results: Totally 64.38% were sleep deprived during the school days, 86.78% went to bed too late, 46.51% had a social jetlag of ≥1 h, and 37.44% took a nap every day(Incluldes holidays and school days). Social jetlag length was statistically different between grades( F =6.97, P < 0.01 ). Girls[(0.95±0.65)h] shown significantly higher social jetlag than the boys[(0.76±0.59)h]( t=6.19, P <0.01). Later bedtime on weekends, later wake up time on weekends and poor sleep behavior were risk factors for overweight and obesity in junior high school students( OR=1.20, 1.14, 1.04, P <0.05). Conclusion Junior high school students had less sleep and later bedtimes with the increase of grade, and weekend bedtimes,wake up times and poor sleep behavior were independently associated with the risk of overweight and obesity in junior high school students. Parents and schools should be instructed to pay attention to their sleep health and carry out adolescent sleep health guidance.

Cryptosporidium andersoni ATP-binding cassette (CaABC) is an important membrane protein involved in substrate transport across the membrane. In this research, the nucleotide binding domain (NBD) of CaABC gene was amplified by PCR, and the eukaryotic expression vector of pEGFP-C1-CaNBD was reconstructed. Then, the recombinant plasmid of pEGFP-C1-CaNBD was transformed into the mouse intestinal epithelial cells (IECs) to study the iron transportation function of CaABC. The results indicated that NBD region of CaABC gene can significantly elevate the transport efficiency of Ca2+, Mg2+, K+, and HCO3 - in IECs (P<0.05). The significance of this study is to find the ATPase inhibitors for NBD region of CaABC gene and to inhibit ATP binding and nutrient transport of CaABC transporter. Thus, C. andersoni will be killed by inhibition of nutrient uptake. This will open up a new way for treatment of cryptosporidiosis.
ATP-Binding Cassette Transporters/*chemistry/*genetics/metabolism ; Adenosine Triphosphate/metabolism ; Amino Acid Sequence ; Animals ; Calcium/metabolism ; *Cloning, Molecular ; Cryptosporidiosis/parasitology ; Cryptosporidium/chemistry/genetics/*metabolism ; Humans ; Iron/metabolism ; Mice ; Molecular Sequence Data ; Protein Structure, Tertiary ; Protozoan Proteins/*chemistry/*genetics/metabolism ; Sequence Alignment

BACKGROUND:Hand-foot-mouth disease has become a major public health issue in children in China. In the present prospective study we investigated the clinical characteristics and emergency management of children with severe encephalitis associated with NPE caused by enterovirus 71. METHODS:The study was conducted in 2 pediatric intensive care units (PICUs) over a 2-month period. Clinical records were reviewed of critically ill children with severe encephalitis associated with NPE caused by EV71 who were admitted to PICUs during the period of May to June 2008 in Fuyang. RESULTS:We reviewed the complete records of 36 children, of whom 23 (63.9％) were male and 13 (36.1％) female. Their age ranged from 4 to 48 months, with an average of 15.8 months. Al children except one were under 3 years of age. The overal mortality in these children was 19.4％. The average duration of critical life threatening signs and symptoms was 2.1 days (12 hours-5 days). Nervous system diseases included brainstem encephalitis in 27 children (75％), brainstem encephalitis associated with myelitis in 6 children (16.7％), and general encephalitis in 3 chidren (8.3％), respectively. In 12 patients of NPE (33.3％) pink or bloody bubble sputum and asymmetric pulmonary edema or hemorrhage was the primary manifestation but no typical exanthema was observed. Five children died of acute onset of NPE and / or pulmonary hemorrhage with rapid progression of cardiopulmonary failure within hours after admission. Therapeutic management consisted of mechanical ventilation and administration of mannitol, methylprednisolone, intravenous immunoglobulin (IVIG) and vasoactive drugs, associated with the need of fluid volume resuscitation in 9 (25％) of the 36 children. CONCLUSIONS:In children less than 3 years of age found to be affected by severe EV71 encephalitis associated with NPE, one fifth may die. The major organ systems infected by severe EV71 include the central nervous system, the respiratory system, and the cardiovascular system. Early diagnosis and evaluation, respiratory support, treatment of intracranial hypertension, and mainttenance of function of the cardiovascular system are the most important therapeutic measures.

OBJECTIVETo investigate how transient low dose of hydroperoxide pretreatment prevents cardiac ischemia/reperfusion injury.

METHODSSD rats were divided into 4 groups: sham operation (Sham), standard ischemia/reperfusion (I/R), ischemic preconditioning (IPC) and IR preceded by low H2O2 treatment. Cardiac function and injury parameter were compared among groups.

RESULTSIPC protected reperfusion injury and improved cardiac function. Low H2O2 treatment played a role in cardioprotection similar to IPC. Low H2O2 was indeed generated in the early phase of simulated ischemia and attenuated cytochrome c release induced by high Ca2+ in isolated mitochondria.

CONCLUSIONLow H2O2 plays a critical role in cardioprotection probably by inhibiting mitochondrial permeability transition.

Animals ; Hydrogen Peroxide ; administration & dosage ; Ischemic Preconditioning ; methods ; Male ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; prevention & control

OBJECTIVETo separate high-quality sperm by PureSperm centrifugation applied to intrauterine insemination (IUI) cycles.

METHODSWe compared the separate results after washing the semen with one-layer and two-layer PureSperm gradient centrifugation methods and two-layer Percoll gradient centrifugation method, and used the recovered high-quality sperm for IUI.

RESULTSThe density of the sperm washed with one-layer PureSperm centrifugation method was significantly higher than that washed with two-layer Percoll and two-layer PureSperm centrifugation methods(P < 0.01), but there were no differences in all the results between the use of two-layer Percoll and two-layer PureSperm(P > 0.05). No significant differences in the motility, teratozoospermia and IUI results were found when the three methods were used for sperm preparation(P > 0.05). The percentage of morphologically normal sperm was markedly increased, and the non-sperm components such as leucocytes, epithelial cells and cellular fragments were significantly reduced after washed by the two methods.

CONCLUSIONPureSperm centrifugation is a safe, efficient and easy method for separating high-quality sperm on intrauterine insemination cycles.

Cell Separation ; methods ; Centrifugation, Density Gradient ; Female ; Humans ; Insemination, Artificial ; Male ; Spermatozoa ; cytology

OBJECTIVETo study the effects of carbamazepine on serum metabolic profiles in rats using nuclear magnetic resonance (NMR) spectroscopy.

METHODSTwenty-four healthy male Wistar rats were randomized into 4 groups (n=6) for daily intragastric administration of high-, medium- or low-dose carbamazepine or distilled water (control) for 7 days. Blood samples were collected from the abdominal aortic under anesthesia after the treatment to determine serum carbamazepine concentration using high-performance liquid chromatography. ¹H nuclear magnetic resonance (¹H NMR) spectra were acquired for pattern recognition analysis. Histopathological changes of the renal and liver tissues of the rats were also examined.

RESULTSSteady-state blood concentration of carbamazepine in high-, medium- and low-dose groups were 14.64 ± 1.41, 8.54 ± 1.19, and 4.56 ± 0.64 µg/ml, respectively. Slight liver swelling was found in high-dose group, but none of the groups showed renal pathologies. Compared with the control group, the high-dose carbamazepine group showed lowered serum concentrations of 1,3-diaminopropane, deoxycorticosterone, 7-dehydrocholesterol, betaine, beta-alanine, L-cystathionine, 4-methyl-2-oxovaleric acid, and creatine with increased levels of saccharides, lactate, succinic acid, acetyl phosphate, and adipic acid. Principal component analysis revealed significant differences of the metabolites between carbamazepine-treated groups and the control group. The metabolic profiles showed no differences in the kinds of metabolites although the concentrations of the metabolites varied between the carbamazepine groups.

CONCLUSIONSCarbamazepine significantly affects metabolism in normal rats. This finding provides evidence for clinical drug monitoring and drug safety of carbamazepine. NMR technique has important values for pharmacodynamic and toxicological evaluation of drugs.

Animals ; Carbamazepine ; blood ; Kidney ; pathology ; Liver ; pathology ; Magnetic Resonance Spectroscopy ; Male ; Metabolomics ; Principal Component Analysis ; Rats ; Rats, Wistar