Objective To investigate the roles of somatostatin(SS)positive intemeurons in the development and compensation of temporal lobe epilepsy.Methods Piloearpine-induced epilepsy rat model was established.Immunohistochemistry method was used to detect number changes and axonal sprouting of SS positive intemeurons in different domains of the hippocampus at difierent time points.Degeneration of SS positive interneurons and their neurophils were detected by the double immunofluorescence staining with SS and Fluoro-Jade B(FJB)at 7 and 60 days after status epilepticus (SE).Results In the exoerimental rat group,the number of SS positive neurons decreased in each hippocampal domain,and it reached the lowest at 7 days post-SE(There were 11.1±3.3 in hilus,2.8±0.9 in CA1region and 1.8±0.7 in CA1region,t=13.519,9.644 and 8.808,all P<0.01).In chronic phase,the number of SS neurons gradually recovered,and exceeded the control group in CA1 area at 60 days post-SE(12.8±1.5 vs 8.8±1.3,t=-4.506,P<0.01),however,the number of SS neurons in the hilus(25.5±4.6)and CA1 area(4.8±0.8)remained significantly less than normal levels(t value were 4.691 and 3.953.both P<0.01).Increased SS positive fibers were found in the lacunosum-molecular (1m)layer and outer molecular layer of dentate gyrus after 30 days post-SE,and numerous SS positive fibers were seen threnghout the layers of area CA1 at 60 days post-SE.Double immunofluuorescence revealed that a few SS positive interneurons and fibers were also labeled by FJB in area CA1 at 7 days post-SE and in CA domain/hilus at 60 days post-SE.Conclusions SS intemeurons loss plays an important role in the development of temporal lobe epilepsy.The loss is partially caIlsed by the degeneration and death of neurons;SS positive neurophils increase within area CA1 in chronic phase may play a significant role in the generation and compensation of temporal lobe epilepsy.

Objective To study the expression of epidermal growth factor receptor (EGFR) in cervical car-cinoma and cervical intraepithelial neoplasia(CIN),and to elucidate its relation with the genesis, infiltration, metas-tasis and prognosis of cervical carcinoma. Methods EGFR was determined by means of S-P immunohistochemistry in tissue of 100 cases of cervical carcinoma,60 cases of CIN and 40 cases of controls. Results The overexpression rates of EGFR were 0% (0/40), 51.67% (31/60),78.00% (78/100), respectively in normal cervical epithelium, CIN and cervical tumor tissues. The overexpression rate of EGFR was significantly higher in cervical tumor tissue than in control group(P<0.01). The overexpression of EGFR didn't demonstrate significant association with clinical staging, tumor size, pathological type, differentiation, cervical invasion depth, cervical canal invasion, lymphnode me-tastasis or the prognosis of cervical neoplasm (P>0.05). Conclusion Overexpression of EGFR is worsened with the severity of cervical lesion, suggesting that overexpression of EGFR is correlated with the genesis of cervical neo-plasms,which may be a valuable biological indicator of cervical carcinoma,but is not correlated with clinical patho-logical features and prognosis of cervical carcinoma.

Objective To compare the fluorescence intensity and duration of qdots streptavidin conjugate (QDs-SA) with Cy3 as the molecular probe of β amyloid precursor protein (APP), and to provide evidence for early molecular imaging and diagnosis of Alzheimer's dissease (AD). Methods With the help of laser scanning confocal microscope and flow cytometry, the flurescence probe based on the QDs-SA was used to detect APP in HEK293 cells stably transfected pcDNA3.1/APP, and to compare with conventional fluroimmunoassay Cy3. Results The immunofluorescence staining detection indicated APP expression was mainly located in the plasma membrane. The mean fluorescence intensity of QDs-SA (34.2336±4.2455) was greater than that of Cy3 (21.6023±3.0102)under the confocal fluorescence microscope (P<0.05). After persistent exciting for 12 min, the fluorescence intensity of APP stained by QDs-SA decreased by 27.87%. The other stained by Cy3 decreased by 79.60%. The positive rate of APP staining had no significant difference between the QDs-SA(54.4700±3.4433)% and Cy3 (54.3800±8.5229)% by flow cytometry, but the mean fluorescence intensity had statistical significance(P<0.05). The QDs-SA (1 045.4167±47.3623) was significantly higher than the mean fluorescence intensity of Cy3 (658.5467±55.0591). Conclusion QDs-SA fluorescence probes can effectively recognize APP and are sensitive and exceptionally photostable, suggesting that QDs-SA fluorescence probes could be a potential method in APP detection and offer a novel way for the diagnosis of Alzheimer's disease.

The anatomical morphology of root canal systems in maxillary second molars (MSMs) is complex and shows diverse variations, which leads to challenging root canal treatments that could end in failure. Therefore, understanding the diverse nature of root canal anatomy is an important prerequisite for the successful treatment of MSMs. The fused root is among the most prevalent root variants of MSMs, exhibiting a distribution rate ranging from 23.9% to 42.25% within the Chinese population. Fused roots are often accompanied by complex root canal fusion, as the incidence of root canal fusion in type VI fused roots of MSMs is 90.5% within the Chinese population. There are several treatment strategies for the root canal variations in MSMs, including the location of the root canal orifice and clearing and filling of the isthmus within the fused root canal. Cone-beam computed tomography, dental operating microscopy, and digital dynamic and static navigation technologies can be employed to accurately identify the root canal variations associated with fused roots. In the treatment of fused root canals, for the cleaning and filling of the isthmus in fused canals, enhanced chemical preparation, timely application of laser-assisted irrigation, photodynamic therapy, and micro-apical surgery significantly improve the success rate of endodontic procedures. The treatment strategies and prevalence of root canal variation of MSMs from a native Chinese population were summarized in this paper to provide guidance and reference for the successful treatment of MSMs.

UNLABELLEDTo determine the contents of aflatoxin B1, B2, G1 and G2 in Nelumbinis Semen using on-line post-column photochemical derivatization-HPLC-FLD method and verify the method by LC-MS method.

METHODThe samples were extracted with MeOH-H2O (80: 20) and purified with inmunoaffinity column, aflatoxins were analyzed by HPLC-FLD with post-column photochemical derivatizaton. The positive samples were further confirmed by LC-MS/MS.

RESULTOn optimum conditions, aflatoxin B1, G1 ranging 0.3-30 mg x L(-1) showed a good linear relationship with aflatoxin B2, G2 ranging 0.09-9.0 mg x L(-1) with r >0.999 9. The recoveries ranged between 86.7% and 99.1%, with RSDs all bellow 4.87%. LOD of aflatoxin B1, B2, G1 and G2 were 0.08, 0.03, 0.10, 0.03 microg x kg(-1), respectively. Among 20 Nelumbinis Semen samples, 14 were found to contain aflatoxin B1 ranging from 0.40 to 586 microg x kg(-1). The total content of aflatoxin B1, B2, G1 and G2 were between 0.40 and 602.5 microg x kg(-1). By LC-MS/MS method, the same fragment ions were founded in samples and the control group at the same retention times, ruling out the possibility of false positive samples.

CONCLUSIONThe method is simple, highly sensitive and reproducible for the determination of aflatoxins in Nelumbinis Semen.

Aflatoxins ; analysis ; chemistry ; isolation & purification ; Chromatography, High Pressure Liquid ; Chromatography, Liquid ; Drugs, Chinese Herbal ; chemistry ; Food Contamination ; Reproducibility of Results ; Sensitivity and Specificity ; Tandem Mass Spectrometry

OBJECTIVETo establish a new diagnostic method for Down's syndrome using polymerase chain reaction (PCR).

METHODSDNA extracted from five healthy individuals and five Down's syndrome patients was amplified in six specific tetranucleotide repeat loci on chromosome 21 using PCR. An accurate diagnosis was made by analyzing allelic distribution at each locus.

RESULTSAll Down's syndrome patients were identified as having at least two loci with three alleles, while none of the healthy individuals had three alleles. In addition, when two alleles were identified for a particular locus in the Down's syndrome samples, it was more likely that the intensity ratio between the two alleles was close to 2:1.

CONCLUSIONThe molecular method can provide a fast, accurate, and economical alternation for the traditional cytogenetic diagnostic method for Down's syndrome.

Cytogenetic Analysis ; methods ; Down Syndrome ; diagnosis ; genetics ; Humans ; Polymerase Chain Reaction

To improve the standard of quality control of tazobactam and its preparations in China, national reference standard of tazobactam impurity A was developed. After tazobactam impurity A was synthesized, its structure was validated by infrared (IR), mass spectrometry (MS) and nuclear magnetic resonance (NMR), and its content uniformity and short-term stability were measured and investigated. Then, water content and residue on ignition of impurity A were determined, and its purity was determined using high performance liquid chromatography (HPLC) with 10 mmol/L ammonium acetate solution-acetonitrile (98∶2) as the mobile phase. Mass balance method was used to determine the content of the first batch of tazobactam impurity A national standard substance. Meanwhile, nuclear magnetic quantitative method was used to calculate the content, which was mutually verified with the mass balance method. The developed reference material of tazobactam impurity A is consistent with the maximum degradation impurity in tazobactam system applicability solution and the reference material of tazobactam related substance A contained in USP41. Within the 95% confidence range, the ratio of inter- and intra-bottle variance of impurity A after separation was 0.61 (< F0.05(11,12)), proving that the uniformity was satisfying. The contents of organic impurity, water content and inorganic impurity in impurity A were 0.90%, 1.24% and 0.25%, respectively. The content of impurity A was determined to be 97.6% by mass balance method, which was basically consistent with the result of nuclear magnetic quantitative method (97.1%). Under the condition of 25 °C, the area normalized purity of impurity A was 99.1% at 0, 3, 5 and 10 days, proving that the sample was stable at room temperature for 10 days. Finally the first batch of national standard substance of tazobactam impurity A was established successfully.

Objective:To investigate the effect of ionizing radiation on the ferroptosis of skin cells and the potential therapeutic strategy of ferroptosis inhibitor Ferrostatin-1 (Fer-1) on irradiated skin cells.Methods:HaCaT cells were pre-treated with Fer-1 before X-ray irradiation. After irradiation, CCK-8 assay and LDH release assay were used to detect cell viability and cell death, flow cytometry was used to detect the lipid peroxidation levels, crystal violet staining assay was used to detect colony forming ability, and the expressions of ferroptosis related proteins ACSL4 and GPX4 were detected by Western blot.Results:The cell viability of HaCaT cells was significantly decreased ( t=5.63, 8.74, P<0.05) and the release of LDH was significantly increased ( t=3.98, 5.08, 9.27, P<0.05) after different doses of X-ray irradiation. The cell viability was improved ( t=5.79, P<0.05) and the release of LDH was reduced ( t=12.36, 11.96, 18.13, 9.96, P<0.05) after the pre-treatment with Fer-1. The lipid peroxidation levels of HaCaT cells were significantly increased ( t=9.59, P<0.05) and the clonogenic survival ability were reduced ( t=4.26, P<0.05) after 10 Gy X-ray irradiation, while Fer-1 pre-treatment reduced ( t=6.48, 17.04, P<0.05) the increase of lipid peroxidation level induced by X-ray irradiation and also effectively restore ( t=3.96, P<0.05) the clonogenic survival ability. The expressions of ACSL4 and GPX4 were decreased after 10 Gy X-ray irradiation, while they recovered to normal level ( t=5.23, 7.16, 4.78, 8.29, 6.43, P<0.05) after the pre-treatment with Fer-1. Conclusions:Ferroptosis inhibitor Fer-1 alleviates the progress of radiation-induced skin injury by inhibiting ferroptosis after ionizing radiation at the cellular level, which provides a potential strategy for the protection of radiation injury.

Objective:To analysis the incentive level of family doctors in primary medical and health institutions in Beijing, and to explore its influencing factors, so as to provide references for promoting family doctors′ contract service.Methods:From October to December 2021, 40 family doctors were randomly selected from 135 urban community health service centers in 8 districts of Beijing, and a survey was conducted on basic demographic information, institutional organizational capacity evaluation, and family doctor incentive level evaluation (including four dimensions of work value, organizational environment, personal development, and reward compensation), and the influencing factors of family doctor incentive level was analyzed. Chi-square test and Pearson correlation analysis were used for univariate analysis, and multiple linear regression analysis was used for multivariate analysis.Results:A total of 4 568 family doctors were included, and the score of family doctors′ incentive level was 3.75±0.81, among which the work value score was the highest(3.89±0.77), followed by the organizational environment score(3.69±0.92) and personal development score(3.75±0.90), and the lowest score was reward(3.75±0.90). Age, education, professional title, working years and average total working hours per week negatively affected the incentive level( P<0.05), while the average monthly income, the frequency of attending training and further study, and the organizational ability of the organization positively affected the incentive level( P<0.05). Conclusions:The overall incentive level of family doctors in primary medical and health institutions in Beijing needed improvement, and there were many factors that affect the incentive level of family doctors. It was recommended to appropriately increase the salary and benefits of family doctors, reasonably arrange the workload of family doctors, strengthen the training mechanism of family doctors, and strengthen the organizational capacity building of primary medical and health institutions.

Objective:To analyze the accuracy of lung ultrasound and chest X-ray in the diagnosis of neonatal pulmonary disease.Methods:We prospectively collected newborns that needed chest X-ray examination to diagnose pulmonary disease from twelve neonatal intensive care units across the country between June 2019 and April 2020.Each newborn was examined by lung ultrasound within two hours after chest X-ray examination.All chest X-ray and lung ultrasound images were independently read by a radiologist and a sonographer.When there was a disagreement, a panel of two experienced physicians made a final diagnosis based on the clinical history, chest X-ray and lung ultrasound images.Results:A total of 1 100 newborns were enrolled in our study.The diagnostic agreement between chest X-ray and lung ultrasound(Cohen′s kappa coefficient=0.347) was fair.Lung ultrasound(area under the curve=0.778; 95% CI 0.753-0.803) performed significantly better than chest X-ray(area under the curve=0.513; 95% CI 0.483-0.543) in the diagnosis of transient tachypnea of the newborn( P<0.001). The accuracy of lung ultrasound in diagnosing neonatal respiratory distress syndrome, meconium aspiration syndrome, pneumonia and neonatal pulmonary atelectasis was similar to that of chest X-ray. Conclusion:Lung ultrasound, as a low-cost, simple and radiation-free auxiliary examination method, has a diagnostic accuracy close to or even better than that of chest X-ray, which may replace chest X-ray in the diagnosis of some neonatal lung diseases.It should be noted that both chest X-ray and lung ultrasound can only be used as auxiliary means for the diagnosis of lung diseases, and it is necessary to combine imaging with the clinical history and presentation.