Factors related to career development and transformation of rehabilitation therapists / 中国康复理论与实践

ObjectiveTo investigate the current situation of rehabilitation therapists' work, and analyze the factors related to their career development and transformation. MethodsFrom September, 2022 to January, 2023, 153 rehabilitation therapists in Weifang were investigated with a cross-sectional questionnaire, using general questionnaire, Job Satisfaction Scale for Grassroots Health Technicians, Social Responsibility Scale, Job Role and Identity Inventory, and Employee Turnover Scale. ResultsThe majority of rehabilitation therapists interviewed were male (52.28%), under 35 years old (88.24%), with a bachelor's degree (77.78%), income less than 5 000 yuan a month (46.40%), and less than five years of service (48.36%). The work time was (7.78±0.84) hours a day, (5.39±0.51) days a week. The favorable rate of the physical environment of work was 67.32%, and the favorable rate of the interpersonal relationship environment of work was 80.39%. The score of professional identity was (3.61±0.84), the score of job satisfaction was (3.62±0.97), the score of social responsibility was (3.53±0.79), and the score of turnover was (2.39±1.10). Education level, job satisfaction, and social responsibility were the main factors related to the employee turnover (P < 0.05). ConclusionThe overall educational level of rehabilitation therapists is relatively low, and the human resource structure needs to be optimized. There is a significant difference between academic education and continuing education, and career development needs to be improved. The main factors related to career development and transformation are education level, job satisfaction, and social responsibility.

The prevalence and associated factors of functional constipation among primary and middle school students in Shaanxi Province / 中国学校卫生

Objective@#To understand the prevalence and associated factors of functional constipation(FC) among primary and middle school students in Shaanxi Province, in order to provide a basis for preventing FC in students.@*Methods@#A stratified cluster random sampling method was used to conduct a questionnaire survey on 9 133 primary and middle school students aged 10-18 in eight primary and secondary schools in Shaanxi Province from March to September,2017. Chi square test and multivariate Logistic regression were used to analyze the associated factors of FC among primary and middle school students in Shaanxi Province.@*Results@#There were a total of 364 students meeting the FC Rome IV diagnostic criteria, with a prevalence rate of 3.99%. Among them, there were 155 male students with a prevalence rate of 3.43%, and 209 female students with a prevalence rate of 4.53%. Univariate analysis showed that gender, breastfeeding, separation from parents, long term school meals, types of staple foods, breakfast frequency, cold foods eating frequency, spicy foods eating frequency, fried food eating frequency, pickled food eating frequency, desserts eating frequency, vegetables eating frequency were related to FC, and the differences were statistically significant ( χ 2=7.30,18.75, 20.89,35.54,22.43,16.05,21.31,13.97,10.33,23.96,16.25,17.74, P <0.05). Multivariate Logistic regression analysis showed that female, non breastfeeding, separation from parents, long term school meals, low consumption of staple food/staple food dominated by rice, and never eating vegetables were positively correlated with FC( OR =1.37,1.96,1.52,2.07,1.76,1.58,2.31, P < 0.05 ).@*Conclusions@#The prevalence of functional constipation is higher in primary and middle school students. Attention should be paid to factors related to students dietary habits and food classification to prevent the occurrence of FC in primary and middle school students.

2011 to 2021 rehabilitation professionals distribution from system of China Disabled Persons' Federation using geographical gravity model / 中国康复理论与实践

ObjectiveTo investigate the distribution and trend of rehabilitation personnel of China Disabled Persons' Federation (CDPF) system and the people with disabilities (PWDs) using geographical gravity model. MethodsBased on ArcGIS and statistical data, the distribution of geographical center of gravity of the rehabilitation personnel of the CDPF system from 2011 to 2021 was analyzed. According to the economic development, the areas were divided into three regions, and the eastern region included eleven provincial units, the central region includes eight provincial units, and the western region included twelve provincial units. ResultsCompared with 2011, rehabilitation staffs per thousand PWDs increased at 107.5% in 2021, 81.1%, 114.2% and 174.1% for the eastern, central, and western regions, respectively; professional staffs increased at 190.5%, 148.8%, 284.6% and 280.6% for the eastern, central, and western regions, respectively; managerial staff increased at 80.0%, 46.8%, 554.3% and 128.1% for the eastern, central, and western regions, respectively. Compared with 2011, the geographical center of gravity of the rehabilitation personnel moved about 330.9 km in 2021, while the geographical center of gravity of the PWDs moved about 169.64 km. ConclusionThe rehabilitation personnel in the CDPF system is the most in the eastern region and least in the western region. The tracks of the geographical center of gravity of the three kind of rehabilitation personnel in the CDPF system are relatively consistent. The rehabilitation personnel in the eastern region are more concentrated than those in the western region, and the density of the PWDs is more westward than that of the rehabilitation personnel, and coordination is not a perfect match yet. It is necessary to strengthen the rehabilitation personnel allocation in the western region, to balance distribution of human resources for rehabilitation of PWDs among regions.

Serum Ferritin and the Risk of Metabolic Syndrome: A Systematic Review and Dose-Response Meta-Analysis of Cross-sectional Studies / 生物医学与环境科学（英文）

Objective@#This study aims to assess the dose-response relationship between serum ferritin (SF) and metabolic syndrome (MetS) in the two sexes.@*Methods@#We searched for articles on PubMed, the Cochrane Library, EMBASE, and the Web of Science databases that were published from 1950 to 2020. The summary odds ratio ( @*Results@#This study included 14 studies and 74,710 samples. The results of the classical meta-analysis showed that SF was positively associated with MetS ( @*Conclusions@#Our study shows that SF is significantly and positively associated with MetS, and the risk in the male population is higher than that in the female population. This finding also supports the recommendation of using SF as an early warning marker of MetS.

Drugs and drug delivery strategies for treatment of pulmonary arterial hypertension / 药学学报

Pulmonary arterial hypertension (PAH), also named as a cancer of cardiovascular disease, is a rare disease and has complicated pathogenesis. Recently, there are more understandings of PAH pathogeneses. According to the pathogenesis and active pathways, the clinically used drugs are classified into several groups incluidng prostacyclin analogues and prostacyclin receptor agonists, endothelin receptor antagonists, phosphodiesterase-5 inhibitors, soluble guanylate cyclase inhibitors, etc. To elevate the efficacy of the drugs, numerous drug delivery systems are developed. This review mainly summarized the pathological mechanism of PAH, drugs and drug delivery approaches in the treatment of PAH.

The Risk Factors of Thrombosis in Patients with Philadelphia Chromosome-negative Myeloproliferative Neoplasms / 中国实验血液学杂志

OBJECTIVE@#To investigate the overview of thrombosis in myeloproliferative neoplasms(MPN) patients, and to explore the risk factors of thrombosis at diagnosis and during follow-up.@*METHODS@#The clinical data of 388 MPN patients treated in our hospital were collected. The patients were followed up by outpatient and phone. The risk factors of thrombosis were analyzed by statistical methods.@*RESULTS@#Among 388 MPN patients, 161 patients (41.49%) showed thromboses at diagnosis or during follow-up. Among them, 92.55% were arterial thromboses, 146 cases (96.27%) were complicated with thromboses at diagnosis, and 36 cases (11.46%) showed newly thromboses or progression of previous thromboses among the 314 received full follow-up patients. Age (P＜0.001, HR:1.033, 95%CI:1.016-1.051), JAK2V617F mutation (P=0.037, HR:1.72, 95%CI: 1.033-2.862), hypertension (P＜0.001, HR:2.639, 95%CI:1.659-4.197) and hyperlipidemia (P＜0.001, HR:2.659, 95%CI:1.626-4.347) were the independent risk factors affecting thrombosis at diagnosis of the patients. During the follow-up, age (P=0.016, HR:1.032, 95%CI: 1.006-1.059) and previous thrombosis history (P=0.019, HR:2.194, 95%CI: 1.135-4.242) were the independent risk factors affecting the progression of thrombosis at different sites or on the basis of the previous thrombosis in the patients.@*CONCLUSION@#Patients with advanced age, JAK2V617F mutation or complicated with hypertension and hyperlipidemia shows a higher risk of thrombosis at diagnosis, while the patients with advanced age or previous thrombosis history shows a higher risk of progression of thrombosis during the follow-up.

Effect of Biling Qutong Prescription on SIRT3 Protein Expression and URAT1 mRNA in Skeletal Muscle of Diabetic Gout Rats / 中国实验方剂学杂志

Objective: To observe the effect of phlegm and blood stasis on the expressions of sirtuin 3(SIRT3)protein and urate transporter 1(URAT1) mRNA in skeletal muscle of diabetic rats with gout. Method: The 40 healthy rats, excepting the normal group, the remaining groups were fed with high-fat diet combined with low-dose streptozotocin solution (40 mg·kg-1) once a day, with blood glucose "16.7 mmol·L-1" as the criterion for the diabetes model. After 4 days, the 5% sodium urate solution was injected into the joint cavity once to induce the gout model. After the successful modeling, the Biling group (10 g·kg-1), the indomethacin group (5 mg·kg-1) and the pioglitazone group (10 mg·kg-1) continued to be administered for 21 days. The normal group and the model group were given the same amount of normal saline. The expression of SIRT3 protein in skeletal muscle tissue was determined by Western blot, URAT1 mRNA expression in bone tissue was detected by quantitative real-time fluorescence polymerase chain reaction(Real-time PCR),and blood was collected to measure blood glucose (GLU), blood uric acid (UA) and C-reactive protein (CRP). Result: Compared with the normal group, GLU, UA and CRP in the model group were significantly increased (PPPPPPPPConclusion: Biling Qutong prescription with effects in purging turbidity, detoxifying and dredging collaterals can significantly reduce the content of serum inflammatory factor CRP, significantly increase the protein expression of SIRT3 in skeletal muscle tissue of model rats, lower the content of URAT1 mRNA, reduce the blood glucose and blood uric acid levels in diabetic gout rats, and protect joints.

An analysis of assessment results of prevention and control of occupational hazards in a city / 中华劳动卫生职业病杂志

Objective@#To investigate the current status of prevention and control of occupational hazards in a city in 2017, to understand the capability to prevent and control occupational hazards and the level of occupational health supervision and management, and to propose measures to urge employers to assume the main responsibility for the prevention and control of occupational diseases.@*Methods@#An analysis of the main factors influencing the prevention and control of occupational hazards in the city was performed to screen out six semi-quantitative assessment indicators (including the training of the main responsible persons and occupational health management personnel in companies) and four qualitative assessment indicators (including the coverage of supervision and inspection of occupational hazards performed by the district safety supervision department) , which could be used to measure the prevention and control effects of regional occupational hazards. Each indicator was scored. The typical investigation method was used to do data review and on-site inspection of 170 companies, 17 district-level occupational health supervision departments, and 16 sub-district (township) occupational health supervision departments in the city from October to December, 2017. The prevention and control of occupational diseases in each district was scored, and the completion rate and completion situation of each indicator in the city were analyzed.@*Results@#The mean score of prevention and control of occupational hazards in the city was 84.9. The scores of two districts were relatively high, being 88.9 and 88.7, respectively; the scores of 9 (52.9%) districts were higher than 85. The pass rate of training for the main responsible persons and occupational health management personnel in companies in the city was 95.9%, the pass rate of occupational health training for workers was 84.7%, the pass rate of occupational health examination for workers was 96.5%, the pass rate for the inspection of occupational hazardous factors in workplaces was 95.3%, the pass rate for notifying occupational hazards in workplaces is 95.9%, and the pass rate for applying the warning signs of occupational hazards in workplaces was 76.5%.@*Conclusion@#The awareness of the importance of prevention and control of occupational hazards in all districts of the city has been increased, but the effectiveness of occupational health training for workers needs to be strengthened. The supply and demand of occupational health technical services are still not matched, and the ways and methods of occupational health supervision and inspection need to be improved.

A Clinical Observation of Functional Abdominal Pain Syndrome in Patients Treated by Traditional Chinese Spinal Orthopedic Manipulation / 中国结合医学杂志

<p><b>OBJECTIVE</b>To evaluate the clinical effect of traditional Chinese spinal orthopedic manipulation (TCSOM) in treating patients with functional abdominal pain syndrome (FAPS) in comparison with Pinaverium Bromide (Dicetel, PBD), and to assess a possible cause for FAPS.</p><p><b>METHODS</b>Eighty patients with FAPS were randomly and equally assigned to the TCSOM group and PBD group according to the random number table. All patients in the TCSOM group were treated with a maximum of 5 times of spinal manipulations. Patients in the PBD group were instructed to take 50 mg 3 times a day, consistently for 2 weeks. The symptoms of pre- and post-treatment were assessed on a visual analog scale (VAS) pain score. A symptom improvement rating (SIR) was implemented to evaluate the effects of the treatments.</p><p><b>RESULTS</b>The symptoms of 27 cases of the TCSOM group were relieved soon after the first TCSOM treatment and 9 cases were significantly improved. The VAS pain scores in the TCSOM group were significantly lower than those in the PBD group after 2 weeks treatment. According to the SIR based on VAS, the TCSOM group included 30 cases with excellent results, 7 cases with good, and 3 cases with poor. Adverse events to the treatment were not reported. Based on VAS, the PBD group reported 8 cases with excellent results, 10 cases with good and 22 cases with poor. There was a significant difference between the two groups (P<0.01).</p><p><b>CONCLUSIONS</b>The displacement of intervertebral discs and/or vertebra in the thoracic or lumbar region seems to be a contributing factor in the symptoms of FAPS. TCSOM is an effective treatment for FAPS.</p>

Clinical observation on acupressure at Jiaji points for irritable bowel syndrome / 中国针灸

<p><b>UNLABELLED</b>To evaluate clinical efficacy of acupressure at Jiaji points for irritable bowel syndrome (IBS) and explore its pathogenesis and treatment law.</p><p><b>METHODS</b>Sixty outpatient cases of IBS from 2010 to 2012 were selected and randomly divided into an acupressure group and a medication group, 30 cases in each one. The acupressure at Jiaji points was applied in the acupressure group while pinaverium bromide tablet was orally prescribed in the medication group. The bowel symptom scale (BSS) was adapted to sore symptoms before and after the treatment, the improvement rate was adopted and results were analyzed.</p><p><b>RESULTS</b>The difference of BSS score in two groups after the treatment had statistical significance (both P<0.01). The efficacy in the acupressure group was superior to that in the medication group, which had significant difference (P<0.01). The improvement rate was 90.0% (27/ 30) in the acupressure group, which was better than 50.0% (15/30) in the medication group (P<0.01). The location of abdominal pain in IBS was lower abdomen while treatment location was from 11th thoracic vertebra to 1st lumbar vertebra.</p><p><b>CONCLUSION</b>The acupressure at Jiaji points could balance yin and yang in spine to quickly relive symptoms of IBS. The attack of IBS has some relationship with thoracic and lumbar vertebras.</p>

Study on signal transmission characteristics of meridian based on electrical network theory and experiments / 中国针灸

Study on features of acupoints with resistance test in the past half century is reviewed in this article. Mechanism and technology of the method are introduced as well as its shortcomings. The determination method of signal transmission along meridians with the combination of electrical network theories and practice is advanced. And the result of a series experiments on one meridian at the superficial part of the body are given as well. Thus, it is concluded that the signals of the point-in/point-out and the signals along a non-meridian path with the same distance are significantly different, which gives a verification of the feasibility of the method by using electrical network theories to set out characteristics of signal transmission along meridians dynamically.

Metformin versus metformin plus rosiglitazone in women with polycystic ovary syndrome / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Hyperinsulinemia and insulin resistance are present in the majority of women with polycystic ovary syndrome (PCOS). Both metformin and rosiglitazone can improve the ovulation and endocrine disorders of the patients. How about the combination of the two? It is rarely reported. This study aimed to compare the therapeutic efficacy of metformin versus metformin plus rosiglitazone in patients with PCOS.</p><p><b>METHODS</b>Fifty-eight women with PCOS were randomly assigned to two groups. Metformin group (29) was treated with metformin mono-therapy and metformin plus rosiglitazone group (29) was treated with metformin plus rosiglitazone for 6 months. Treatment was discontinued once pregnancy was diagnosed.</p><p><b>RESULTS</b>Fasting insulin, postprandial insulin, the homeostatic model assessment of insulin resistance (HOMA-IR), luteinizing hormone (LH), triglyceride, lower density cholesterol and testosterone level decreased significantly in both groups (P < 0.05). Metformin plus rosiglitazone had a better effect than metformin mono-therapy. Body mass index decreased by 7.8% in metformin group while no significant change in metformin plus rosiglitazone group. There were eight pregnancies, six in metformin plus rosiglitazone group (one abortion) and two in metformin group. There was no congenital anomaly at birth and seven infants developed well at one year's follow-up.</p><p><b>CONCLUSIONS</b>Metformin can improve insulin resistance and imbalance of endocrine hormones. Metformin plus rosiglitazone has a more pronounced therapeutic effect and achieved more pregnancies than mono-therapy with metformin. The use of metformin and rosiglitazone before pregnancy has no obvious side effect on the development of the infants. Our study might suggest that metformin is the better choice in PCOS patients with serious obese and rosiglitazone plus metformin would be more effective in patients with severe insulin resistance or those do not respond to metformin.</p>

Comparison of the systemic vascular resistance and the correlative factors in Han and Korean populations of China / 生理学报

In the present study, the differences in systemic vascular resistance (SVR) and the correlated risk factors between Han and Korean residents were investigated. 1 647 Hans and 876 Koreans from Mudanjiang and Hailin areas of Heilongjiang Province were examined with BIOZ Cardio Dynamics Monitor. A series of factors were determined, including SVR, systemic vascular resistance index (SVRI), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), cardiac output (CO), cardiac output index (CI) and heart rate (HR). The data were analyzed with SPSS 15.0 statistic software. When SVR/SVRI were compared between Han and Korean populations by t-test, it was shown that statistic difference existed in the following age and gender groups: (1) For SVR: male 41-50, 51-60, and 61-70 (P<0.001), 31-40 (P<0.01), 19-30 (P<0.05) age groups; female 15-18, 31-40, 51-60 (P<0.001), 41-50 (P<0.01), and 61-70 (P<0.05) age groups; (2) For SVRI, male 41-50, 51-60 (P<0.05) age groups; female 10-14, 51-60 (P<0.001), 15-18, 31-40 (P<0.01), and 41-50 (P<0.05) age groups. Covariance analysis suggests that, excluding the contributions of gender, age and body mass index (BMI), the differences in SVR/SVRI between the two populations are still significant (P<0.001). Multiple linear regression analysis reveals that SVR difference between Han and Korean populations is attributed to MAP, DBP, CI, SBP, HR; While SVRI difference between two populations is attributed to MAP, DBP, SBP, CI, HR, strongly to weakly, respectively. These results suggest the higher SVR and SVRI are possibly correlated with the relatively higher blood pressure of Korean, compared with that of Han population.

The relationship between percentage body fat, waist-hip ratio and cardiovascular function in the adult females of Heilongjiang province / 中华预防医学杂志

<p><b>OBJECTIVE</b>To analyze the relationship between body fat mass and distribution and cardiovascular function in the adult females of Heilongjiang province.</p><p><b>METHODS</b>Based on the statistic variable random sampling principal, we selected 1903 healthy adult females with ages of 18 - 70 years old in Heilongjiang province to conduct the study. The height, body weight, waist, chest measurement and waist-hip ratio (WHR) were measured. Body components quota including fat weight, lean weight, percentage of body fat (PBF) were taken respectively; systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), cardiac output (CO), cardiac index (CI), stroke volume (SV), stroke index (SI), left cardiac work (LCW) and systemic vascular resistance (SVR) were determined.</p><p><b>RESULTS</b>The PBF and WHR increased with aging, and the PBF of those with ages of 18-, 30-, 40-, 50- and 60 - 70 year's old were (16.86 +/- 5.37)%, (18.43 +/- 4.89)%, (20.99 +/- 5.79)%, (23.47 +/- 5.74)% and (25.77 +/- 6.38)%, respectively (F = 154.46, P < 0.01); and the WHR were 0.77 +/- 0.05, 0.80 +/- 0.05, 0.83 +/- 0.05, 0.85 +/- 0.06 and 0.89 +/- 0.07, respectively (F = 229.84, P < 0.01). The HR, CO, CI, SBP, DBP and LCW were (75.45 +/- 0.35) bpm, (4.42 +/- 0.02) L/min, (2.78 +/- 0.01) L * min(-1) * m(-2), (114.94 +/- 0.40) mm Hg (1 mm Hg = 0.133 kPa), (64.90 +/- 0.28) mm Hg, (4.57 +/- 0.03) kg * m/m(2) respectively in normal PBF groups; whereas the HR, CO, CI, SBP, DBP and LCW in the PBF obesity groups were (77.42 +/- 0.88) bpm, (4.54 +/- 0.05) L/min, (2.88 +/- 0.03) L * min(-1) * m(-2), (120.55 +/- 1.00) mm Hg, (66.56 +/- 0.71) mm Hg and (4.86 +/- 0.07) kg * m/m(2), respectively, F values were 3.182, 9.173, 8.478, 13.497, 2.637, and 10.631, respectively (all P values < 0.05) after the adjustment of age, height and weight, PBF was positively correlated with HR, CO, CI, SI, SBP, DBP and LCW (r values were 0.06, 0.11, 0.10, 0.11 and 0.12, respectively, all P values < 0.05); WHR was positively correlated with CI, SI, SBP, DBP, LCW and SVR (r values were 0.14, 014, 0.19, 0.18, 0.10 and 0.12, respectively, all P values < 0.01) after the adjustment of age, height and weight.</p><p><b>CONCLUSION</b>PBF augmentation and abdominal obesity in females can result in cardiac dysfunction such as cardiac overload, CO increasing and blood pressure rising.</p>

Study of stress distribution in mandibular first premolar restored by composite resin with root screw of different length in different occlusion / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate stress distribution in mandibular first premolar restored by composite resin with root screw of different length in different occlusion.</p><p><b>METHODS</b>An three dimensional finite element model of mandibular first premolar restored by composite resin with root screw was constructed by using spiral CT image reconstruction technique, Mimics, Pro/Engineer, Pro/Mechanica software. Based on this model, stress distribution in dentin, composite resin and root screw was analyzed in the situation of different screw length and different occlusion.</p><p><b>RESULTS</b>When the occlusion was tripod contact and cusp tip-ovoid fossa contact, the stress of dentin, composite resin and root screw were all much less than their compressive strength. And also in this situation, the stress of bond surface between the composite resin and dentin was less than the bond strength of composite resin. The screw was longer but no more than 8 mm, the dentin stress distributes better.</p><p><b>CONCLUSION</b>In the restoration of large area mandibular first premolar crown defection, tripod contact and cusp tip-ovoid fossa contact with 8 mm root screw is recommended.</p>

Characterization of the mRNA profile in ejaculated spermatozoa from healthy fertile men / 中华男科学杂志

<p><b>OBJECTIVE</b>To explore the complexity of mRNA in the ejaculated sperm from healthy fertile men.</p><p><b>METHODS</b>Semen samples were collected from 10 healthy fathers. The swim-up method was adopted to purify the sperm from possible contamination of somatic cells and the spermatozoal total RNA extracted by Trizol was used for SAGE library analysis.</p><p><b>RESULTS</b>A totle of 21 052 SAGE raw tags were sequenced from 877 clones and 2 712 unique tags that occurred at least twice in the library were given further analysis. 19.7% of the unique tags had no match in the existing SAGE map, representing novel genes. Molecular function analysis revealed 67% of unique tags related to protein binding or nucleic acid binding categories, 41% to catalytic activity, 13% to message transducer activity, and 10% to transporter, structural and transcription regulator activity, respectively.</p><p><b>CONCLUSION</b>There exists a complex repertoire of mRNAs in the ejaculated spermatozoa from fertile men.</p>

Study on expression of PS1 in APP-PS1 double gene stably transfected cell lines and its relation to gamma-secretase / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the role of presenilin1 (PS1) in the processing of beta-amyloid precursor protein (APP) to amyloid beta-peptide (Abeta) and its relation to gamma-secretase in the pathogenesis of Alzheimer's disease (AD).</p><p><b>METHODS</b>Several CHO cell lines stably transfected with either wide-type or mutant PS1 (M(146)L) along with APP(751) genes were established. The expression of PS1 and its half-life were determined by immunoprecipitation, Western blotting and pulse-chase experiment. Abeta released into the conditional media was quantitated by ELISA.</p><p><b>RESULTS</b>PS1 transfected CHO cells expressed an expected 45,000 full length protein. This over-expressed full length PS1 was subject to fast degradation with a half-life of less than 1 hour. In contrast to full length PS1, the truncated N-terminal and C-terminal proteins of PS1 were significantly more stable with a longer half-life of nearly 16 hours. Although the total amount of Abeta released into the conditional media did not show a significant difference between wild-type and mutant PS1 (M(146)L) transfected APP cells, mutant PS1 (M(146)L) transfected APP cells increase Abeta(1 - 42) (a subspecies of total Abeta) production with nearly a 2 fold increase, comparing to untransfected or wild-type PS1 transfected APP cells.</p><p><b>CONCLUSION</b>PS1 is involved in the processing of APP to Abeta, a nearly 2 fold increase of Abeta production in mutant PS1 (M(146)L) transfected APP cells indicates that PS1 may be the expected gamma-secretase itself.</p>

Labeling embryonic stem cells with enhanced green fluorescent protein on the hypoxanthineguanine phosphoribosyl transferase locus / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To label embryonic stem (ES) cells with enhanced green fluorescent protein (EGFP) on the hypoxanthineguanine phosphoribosyl transferase (HPRT) gene locus for the first time to provide a convenient and efficient way for cell tracking and manipulation in the studies of transplantation and stem cell therapy.</p><p><b>METHODS</b>Homologous fragments were obtained by polymerase chain reaction (PCR), from which the gene targeting vector pHPRT-EGFP was constructed. The linearized vector was introduced into ES cells by electroporation. The G418(r)6TG(r) cell clones were obtained after selection with G418 and 6TG media. The integration patterns of these resistant cell clones were identified with Southern blotting.</p><p><b>RESULTS</b>EGFP expressing ES cells on the locus of HPRT were successfully generated. They have normal properties, such as karyotype, viability and differentiation ability. The green fluorescence of EGFP expressing cells was maintained in propagation of the ES cells for more than 30 passages and in differentiated cells. Cultured in suspension, the "green" ES cells aggregated and formed embryoid bodies, retaining the green fluorescence at varying developmental stages. The "green" embryoid bodies could expand and differentiate into various types of cells, exhibiting ubiquitous green fluorescence.</p><p><b>CONCLUSIONS</b>This generation of "green" targeted ES cells is described in an efficient protocol for obtaining the homologous fragments by PCR. Introducing the marker gene in the genome of ES cells, we should be able to manipulate them in vitro and use them as vehicles in cell-replacement therapy as well as for other biomedical and research purposes.</p>