Objective We aim to evaluate the value of the current serum creatinine reference interval ( RI ) provided by Industry Standard WS /T 404.5 in clinical practice.Methods The first time serum creatinine levels and urinary albumin /creatinine ratio were obtained from 67 605 adult patients ( <60 years old) who were treated in the First Hospital of China Medical University between October 1, 2014 and September 30, 2015 in this cross-sectional study.Estimated glomerular filtration rate ( eGFR ) calculated by chronic kidney disease epidemiology collaboration (CKD-EPI) equation and urinary albumin /creatinine ratio (ACR) were used to evaluate the clinical practical significance of current and old serum creatinine RIs as the criteria.Results 4.3% of normal subjects based on current RI were showed decreased eGFR, 98% of abnormal subjects based on the current RI were founded to have decreased eGFR . 1378 subjects were evaluated as increased based on current RI but as normal based on old RI , and 93.5% of these subjects were showed decreased eGFR .In addition, ACR was measured in 26 cases, and 18 out of 26 cases (69.2%) were confirmed to have elevated ACR (≥30 mg/g) and proteinuria.On the other hand of analysis, screening positive rates of declined eGFR were 43.6% by old RI and 61.9% by current RI in the subjects with eGFR under 90 ml(min ×1.73 m 2 ), and the performance of the current RI was obviously improved(χ2 =212.648,P <0.001).Conclusions The current reference interval of serum creatinine is favorable for the detection of renal dysfunction in patients .It is recommended that the current reference interval can be applied in the clinical laboratories as early as possible .

Medical microbiology experiment is faced with many problems in online teaching. This study adopts the teaching mode of online live broadcast + operation video + virtual experiment, and make up the operation gap to some extent through operation video and virtual experiment. The mode of assessment is subjective thinking question (closely following the operation process) + experiment design + literature review (focusing on the key technology or new technology of clinical assessment that cannot be carried out due to the limitation of conditions in traditional experiments, such as mass spectrometry, fluorescence quantitative PCR, and G-test), and it is helpful to understand students' mastery of teaching objectives, and the ability of comprehensive application and innovative thinking. The student questionnaire shows that most students hold a positive attitude towards the online experimental teaching mode, and the quality of students' homework shows that most students have a good learning effect.

BACKGROUND:Due to the sudden release and the rapid removal by proteases,platelet-rich plasma hydrogel leads to shorter residence times of growth factors at the wound site.In recent years,researchers have focused on the use of hydrogels to encapsulate platelet-rich plasma in order to improve the deficiency of platelet-rich plasma hydrogels. OBJECTIVE:To prepare self-assembled polypeptide-platelet-rich plasma hydrogel and to explore its effects on the release of bioactive factors of platelet-rich plasma. METHODS:The self-assembled polypeptide was synthesized by the solid-phase synthesis method,and the solution was prepared by D-PBS.Hydrogels were prepared by mixing different volumes of polypeptide solutions with platelet-rich plasma and calcium chloride/thrombin solutions,so that the final mass fraction of polypeptides in the system was 0.1%,0.3%,and 0.5%,respectively.The hydrogel state was observed,and the release of growth factors in platelet-rich plasma was detected in vitro.The polypeptide self-assembly was stimulated by mixing 1%polypeptide solution with 1%human serum albumin solution,so that the final mass fraction of the polypeptide was 0.1%,0.3%,and 0.5%,respectively.The flow state of the liquid was observed,and the rheological mechanical properties of the self-assembled polypeptide were tested.The microstructure of polypeptide(mass fraction of 0.1%and 0.001%)-human serum albumin solution was observed by scanning electron microscope and transmission electron microscope. RESULTS AND CONCLUSION:(1)Hydrogels could be formed between different volumes of polypeptide solution and platelet-rich plasma.Compared with platelet-rich plasma hydrogels,0.1%and 0.3%polypeptide-platelet-rich plasma hydrogels could alleviate the sudden release of epidermal growth factor and vascular endothelial growth factor,and extend the release time to 48 hours.(2)After the addition of human serum albumin,the 0.1%polypeptide group still exhibited a flowing liquid,the 0.3%polypeptide group was semi-liquid,and the 0.5%polypeptide group stimulated self-assembly to form hydrogel.It was determined that human serum albumin in platelet-rich plasma could stimulate the self-assembly of polypeptides.With the increase of the mass fraction of the polypeptide,the higher the storage modulus of the self-assembled polypeptide,the easier it was to form glue.(3)Transmission electron microscopy exhibited that the polypeptide nanofibers were short and disordered before the addition of human serum albumin.After the addition of human serum albumin,the polypeptide nanofibers became significantly longer and cross-linked into bundles,forming a dense fiber network structure.Under a scanning electron microscope,the polypeptides displayed a disordered lamellar structure before adding human serum albumin.After the addition of human serum albumin,the polypeptides self-assembled into cross-linked and densely arranged porous structures.(4)In conclusion,the novel polypeptide can self-assemble triggered by platelet-rich plasma and the self-assembly effect can be accurately adjusted according to the ratio of human serum albumin to polypeptide.This polypeptide has a sustained release effect on the growth factors of platelet-rich plasma,which can be used as a new biomaterial for tissue repair.

Objective:To investigate the effect of 5.8 GHz radiofrequency (RF) radiation on learning and memory along with hippocampal synaptic plasticity in rats, in order to provide theoretical and experimental references for scientific evaluation of potential hazards of 5.8 GHz RF radiation.Methods:A total of 56 healthy adult male Sprague-Dawley rats were randomly divided into sham exposure group ( n=28) and RF exposure group ( n=28). RF groups were exposed to 5.8 GHz RF for 1 h each day in 15 d or 30 d continuously, and the whole-body absorption rate was 1.15 W/kg. The learning and memory ability of rats was tested by Morris water maze (MWM). The hippocampal structure of rats was observed by Nissl stain. The density of dendritic spines in CA1 region of hippocampus was detected by Golgi stain. The expression of synaptic related protein (PSD95, Synaptophysin) in hippocampus was detected by Western blot. The level of hippocampal neurotransmitters was detected by liquid chromatography-mass spectrometry. Results:In MWM experiments, at 15 d and 30 d after RF exposure, there was no statistically significant difference between sham group and RF group in the escape latency, frequency of crossing plateau, percentage of stay time in plateau quadrant and latency of first arrival to the plateau ( P>0.05). Besides, the structure and the number of neurons in the hippocampus, the density of apical and basal dendritic spines of pyramidal neurons in the CA1 region (apical: 5.10±0.20, 4.89±0.24, 4.58±0.27, 4.49±0.24, and basal: 4.81±0.17, 4.79±0.34, 4.20±0.27, 4.22±0.17, named as Sham 15 d group, RF 15 d group, Sham 30 d group, RF 30 d group, respectively), the expression of PSD95 and Synaptophysin and the level of multiple kinds of neurotransmitters in the hippocampus had no significant changes ( P>0.05). Conclusions:In this study, 5.8 GHz RF radiation has no significant influence on the spatial learning and memory ability along with the synaptic plasticity of hippocampal neurons of rats.

Objective:To describe a systematic approach on identification of poisonous mushroom by investigating two cases of Omphalotus guepiniformis poisoning in Jianyang district, Nanping, Fujian province. Methods:Two incidents of food poisoning on 10 migrant workers were investigated. The remaining suspected mushroom samples were collected and the same fresh mushroom specimens were also collected in the following field investigations from the same dead tree and fallen trunk. These mushroom specimens were identified based on morphological and phylogenetic analyses.Results:On November 24 and 26, 2018, 8 and 2 migrant workers from Jianyang District, Nanping ate wild mushrooms and developed acute nausea, vomiting, abdominal pain and other symptoms within 10 to 90 min after consumption. They were diagnosed as mushroom poisoning, with gastroenteritis as the main manifestation. Further analysis showed that the more poisonous mushroom were consumed, the shorter latency and longer duration of nausea and vomiting were resulted. After admission, gastric lavage, catharsis, acid preparation, gastric protection, fluid replenishment and other symptomatic support treatments were given in time, all patients were discharged in 1-3 d. Based on morphological and phylogenetic analyses, the samples were identified as O. guepiniformis. Conclusions:The two incidents were caused by accidental consumption of O. guepiniformis. Awareness education about poisonous mushroom should be provided to migrant workers to prevent more such poisoning incidents in the future.

Lumbar spondylolysis is one of the common diseases of low back pain caused by spinal surgery. Its treatment options vary depending on different conditions, from early conservative ones to late surgical ones. There are still disputes over various conservative treatments, choice of surgical methods and the biomechanics of different internal fixation techniques to repair spondylolysis. Therefore, this review summarizes the clinical outcomes of previous clinical treatments of lumbar spondylolysis and the biomechanical characteristics of various techniques to find the mechanical and evidence-based clinical data that may facilitate the treatment of lumbar spondylolysis.

Objective:To investigate the effect of thoracic X-ray irradiation on the spermatogenesis of adult male mice.Methods:A total of 24 healthy adult male C57BL/6 mice (6-8 weeks old) were randomly divided into radiation group (Radiation) and sham-radiation group (Sham), 12 mice in each group. The area of thoracic irradiation was 1.5 cm× 2 cm, and the dose rate was 3.04 Gy/min, 8 Gy/d for 3 consecutive days, 24 Gy in total. At 7 d and 21 d after thoracic irradiation, the bilateral testes and epididymal tails were stripped and the testicular index was calculated. The morphology of testis was examined by haematoxylin-eosin (HE) staining, then the diameter of seminiferous tubules and the thickness of seminiferous epithelium were measured. The sperms were collected from the bilateral epididymal tails for sperm counting. The level of apoptosis in testis and levels of apoptosis-related proteins were detected by TUNEL and Western blot, respectively.Results:Compared with Sham group, the morphology of testis and epididymis was seriously damaged, the diameter of seminiferous tubules significantly decreased at 21 d after irradiation ( t = 8.93, P < 0.05), and the seminiferous epithelium significantly decreased at 7 d and 21 d after irradiation ( t = 4.24, 12.77, P < 0.05). In addition, the number of sperms significantly decreased ( t = 4.30, 2.98, P < 0.05). The number of TUNEL positive cells in the seminiferous epithelium significantly increased at 7 d and 21 d after irradiation ( t = -2.73, -3.74, P < 0.05). Meanwhile, the level of cleaved Caspase-3 protein significantly increased at 7 d and 21 d after irradiation ( t = -2.96, -2.46, P < 0.05). The concentrations of SCF and GDNF did not change at 7 d after irradiation, but were significantly increased at 21 d after irradiation ( t = -10.46, -5.42, P < 0.05). Conclusions:The thoracic X-ray irradiation could lead to spermatogenesis disorder in male adult mice, and the induction of spermatogenic cell apoptosis and the secretory dysfunction of sertoli cells may be involved.

Objective: To  investigate  the  effect  of  X-ray  on  the  polarization  of  mouse  microglia  BV-2  cells. Methods: BV-2 cells at the logarithmic growth stage were randomly divided into the Sham irradiation group and 10 Gy irradiation group. The latter group was given a single X-ray irradiation at a dose of 1.28 Gy/min for 7 min 49 s. The activation rate of BV-2 cells was observed and analyzed under a microscope at 1, 3, 6, 24 h and 48 h after irradiation.The changes of cell morphology were observed by HE staining and immunofluorescence staining; The levels of M1-type activation markers (TNF-α and IL-1β) and M2-type activation marker TGF-β1 in the supernatant of BV-2 cells were detected by ELISA. The levels of polarization-related proteins of M1-type (CD86 and iNOS) and M2-type (CD206) in BV-2 cells were detected by Western blotting. Results　: Morphological results showed that BV-2 cells became larger, and their protrude became coarse and shorter, showing "amoeba" like changes after 10 Gy X-ray irradiation. Compared with the Sham group, the activation rate of BV-2 cells was significantly increased at 3 h, and reached the peak at 6 h, and began to recover at 48 h after irradiation. ELISA results showed an obvious increase in the level of TNF-α and TGF-β1 48 h after irradiation.The level of IL-1β showed a transient decrease at 3～6 h, increased at 24 h, and reached the peak 48 h after irradiation. Western blotting results showed that CD86 protein level did not change significantly at each time points after irradiation, and iNOS protein level in- creased significantly at 1, 6, 24 h and 48 h after irradiation. A fluctuating change in CD206 protein level was found after irradiation. Conclusion　 10 Gy X-ray irradiation can induce the activation of BV-2 cells in vitro, and the polarization type changes with the time after irradiation.