AIM:To observe the expressions of cathepsin B (CB) and cystatin C (CC) in different stage of diabetic rats and to investigates their potential roles.METHODS:Sixty rats were divided into diabetes mellitus group induced by intravenous injection of streptozotocin (55 mg/kg) and normal group injected with citrate buffer. Ten rats were sacrificed respectively at the end of fourth week,eighth week and sixteenth week in both groups. 24 h urine excretion was collected in rats before sacrifice. The blood and the kidney were also collected. The mRNA and protein expressions of CB and CC in kidney were detected by real time PCR and immunohistochemical staining,respectively.RESULTS:At the end of eighth week,the expression of Ccr,24 h urinary protein excretion,CB,CC in diabetic rats increased significantly,compared to the results at the fourth week (P

ObjectiveTo determine the optimal timing of antenatal taurine supplementation to improve neuron and neural stem cell proliferation in fetal rats with intrauterine growth restriction.Methods Twenty-five pregnant SD rats were randomly divided into five groups (five rats in each group): group A was the control group, group B to E were the fetal growth restriction (FGR) model groups with low-protein diet during the experiment, group C, D, and E were supplemented with taurine [300 mg/(kg·d)] at day 9, 11 and 15, respectively. The birth weight of newborn rats was measured after natural delivery. The rats with body weight two standard deviations lower than the average weight in group A were diagnosed as FGR. There were five litters of newborn rats in each group, and two were randomly selected from each litter, resulting in ten newborn rats in each group. Proliferating cell nuclear antigen (PCNA) and fatty acid binding protein 7 (FABP7) positive cell expression in newborn rat brain tissues were detected by immunohistochemistry. Single factor analysis of variance, LSD tests were used for statistical analysis.ResultsThe average birth weight of newborn rats in group A, B, C, D and E were (6.61±0.45), (4.65±0.23), (5.37±0.17), (5.74±0.21), and (5.00±0.24) g, respectively. Average birth weight was lower in group B than in group A (t=2.447), higher in group D and E than in group B (t=2.306 and 2.306), higher in group D than in group C and E (t=2.306 and 2.306), and the differences were statistically significant (allP<0.05). The positive expression of PCNA in the brain of neonatal rats was mainly located in the nucleus. The number of PCNA positive cells in each high power field (×400) in group A, B, C, D and E was 31.03±5.38, 46.49±4.38, 59.65±5.37, 67.76±5.84, and 53.53±6.94, respectively. The number of PCNA positive cells in group B was higher than that in group A (t=2.110), higher in groups C, D and E than in group B (t=2.110, 2.110 and 2.131), higher in group D than in group C and E (t=2.101 and 2.110), and the differences were all statistically significant (allP<0.05). The positive expression of FABP7 was mainly located in the cytoplasm of neonatal rat brain. The integral optical density (IOD) in group A, B, C, D, and E was 451 733.1± 141 452.3, 207 232.2±60 525.2, 333 766.6±68 412.1, 380 647.4±131 145.9, and 278 967.1±127 630.7, respectively. The IOD in group B was lower than that in group A (t=3.165,P=0.000), higher in groups C, D and E than in group B (t=5.272, 7.132, 2.950), and the differences were statistically significant (allP<0.05). Although the IOD in group D was higher than that in group C, the difference was not significant (t=1.953, P>0.05). The IOD in group D was higher than that in group E, and the difference was statistically significant (t=4.182,P<0.05).ConclusionsAntenatal taurine supplementation can promote neuron and neural stem cell proliferation in rats with FGR. The effect is most obvious on the 11th day of pregnancy, and may lead to the promotion of brain development.

BACKGROUND: Inhibiting the degradation of extracellular matrix in the intervertebral disc can delay the degenerative process of intervertebral disc. Matrix metalloproteinases-3 (MMP3) is considered as a key enzyme for degradation of extracelular matrix components such as type II collagen and aggrecan.
OBJECTIVE:To construct the short hairpin RNA lentiviral vector targeting human MMP3 gene and to detect its efficiency of gene silence by infecting human degenerative nucleus pulposus cells.
METHODS:According to the human MMP3 mRNA (NM_002422.4) sequence, four groups of the short hairpin RNA gene sequences targeting MMP3 were designed, synthesized and annealed to form double stranded DNA fragments, which were connected with the LV3 vectors digested by BamHI andEcoRI enzymes, and then transfected into the competent cels. The positive clones were identified by PCR, and analyzed by sequencing. The packaging and titer of lentivirus were determined after transfecting 293T cells. Human degenerative nucleus pulposus cels were infected with lentivirus vector, and the transfection efficiency of each group was observed under inverted fluorescence microscope. The interfering efficiency was detected by real time-PCR and western blot at 72 and 96 hours.
RESULTS AND CONCLUSION:The ds-oligo DNA was successfully inserted into the lentiviral vector as confirmed by electrophoresis and sequence analysis. The recombinant lentivirus was harvested from 293T cels with a viral titer of 1-5 ×108 TU/mL. RNA interference targeting the GCC AGG CTT TCC CAA GCA AAT sequences with the highest interfering efficiency in MMP3 gene at 72 and 96 hours resulted in suppression of MMP3 mRNA expression by 98% and 72%, respectively; and at 96 hours, the interfering efficiency of protein expression was 57.2%. The recombinant lentivirus vector containing RNA interference targeting MMP3 gene is successfuly constructed, which lays a foundation for further studies on the MMP3 function and gene therapy.

Objective To explore the association between PI3K polymorphisms in insulin signal transduction pathway and Alzheimer's disease (AD)risk.Methods There were three groups,including 112 cases for AD +T2D group,231 cases for only AD group,and 231 cases for healthy controls group.The polymorphisms in PI3K gene was sequenced by PCR and the concentration of PI3K in serum was tested by enzyme -linked immunosorbent assay (ELISA).Results Overall,there was significantly statistical difference in PI3K rs3730087 polymorphism among three groups (χ2 =20.99,P =0.000 3).The CC frequency of PI3K rs3730087 polymorphism in AD with T2D group and AD control group was significantly higher than that in the healthy control group.The PI3K protein level of differ-ent genotype was statistically significant (F =27.450,P <0.000 1).As for CC genotypes of PI3K rs3730087 poly-morphism,the PI3K protein level was statistically different among these three groups (F =8.096,P =0.000 6).Moreover,the PI3K protein level of the three groups was different (F =9.034,P =0.000 1),which in both AD group was lower as compared with healthy control group.Conclusion The study suggested that CC genotype of PI3K rs3730087 polymorphism in insulin signaling transduction pathway might be a risk factor for AD with T2D and it also affects the expression level of PI3K protein.However,the polymorphism is not shown to be exclusive in AD patients with T2D.

Objective:To investigate the early clinical effect of fascia lata autograft bridging combined with the long head of biceps tendon transposition for treatment of irreparable massive rotator cuff tear.Methods:All of 31 cases of massive irreparable rotator cuff tear treated in our hospital from March 2016 to March 2020 were analyzed retrospectively. Among them, 17 cases (10 males, 7 females) were repaired with fascia lata autograft bridging under arthroscopy (patch group), the average age was 61.47±6.63 (ranging from 51 to 72) and 14 cases (4 males, 10 females) were repaired with fascia lata autograft bridging combined with the long head of biceps tendon transposition (combined group), the average age was 62.57±6.11 (ranging from 53 to 71). The operation time, intraoperative blood loss, postoperative complications, visual analogue scale (VAS) of pain before operation, at 1 week and 12 months after operation, Constant-Murley score of shoulder joint and American Association of shoulder and elbow Surgeons (ASES) score before operation, at 6 months and 12 months after operation were compared between the two groups. The outcome of rotator cuff healing was evaluated by MRI 1 year after operation.Results:All patients were followed up for 12-27 months (mean 18.33 ±6.8 months). There was no perioperative complication, and there was no significant difference in operation time between the two groups ( P>0.05) . The VAS score in the patch group was significantly higher than the combined group 1 week after operation ( t=2.09, P=0.048) , and there was no significant difference in VAS score 12 months after operation between the two groups. Constant-Murley score and ASES score in the combined group were significantly higher than the patch group at 6 months after operation ( t=5.23, P<0.001; t=4.45, P<0.001) , and there was no significant difference in Constant score and ASES score between the two groups at 12 months after operation. Constant score and ASES score in the two groups were significantly higher than those before operation. One year after operation, the MRI of the affected shoulder showed that the incidence of autograft patch thinning (Sugaya grade III) was 52.94%, the autograft patch structure failure rate (Sugaya grade IV and V) was 17.65% in the patch group, the autograft patch thinning rate (Sugaya grade III) was 35.71%, and the structural failure rate (Sugaya grade IV and V) was 7.14% in the combined group. The difference was statistically significant (χ 2=7.12, P=0.028) . Conclusion:Fascia lata autograft patch bridging combined with long head of biceps tendon transposition technique for treatment of irreparable massive rotator cuff tear has less pain 1 week after operation and better recovery of shoulder function half a year after operation. MRI showed better patch healing 1 year after operation.

Development of new radiopharmaceuticals is crucial for the advance of nuclear medicine and molecular imaging. In recent years, significant progress has been made in the development of radiopharmaceuticals based on radioactive metal nuclides such as ⁶⁴Cu. Copper is a transition metal element necessary for human physiology. Disorders of copper metabolism not only cause hereditary Wilson disease and Menkes disease, but also play an important role in the development of malignant tumors. In addition to radiolabeling for probes, ⁶⁴Cu can be used for PET diagnostic imaging of copper metabolism disorders. ⁶⁴CuCl₂ is a useful radiotracer that can be used to track the dynamic flow of copper ions in human body copper metabolism by PET imaging. In recent years, many preclinical and clinical studies of ⁶⁴CuCl₂ radiotracer have achieved good results, and have attracted a lot of attention in the field of nuclear medicine and molecular imaging. In this article, the progress in the development of ⁶⁴CuCl₂ as a radiotracer for PET diagnostic imaging of hereditary copper metabolism disorders and copper hypermetabolic tumors is reviewed, and further research studies and potential clinical application of ⁶⁴CuCl₂ PET/CT imaging is prospected.

OBJECTIVE: To explore the effect of chitosan (CS) hydrogel loaded with tendon-derived stem cells (TDSCs; hereinafter referred to as TDSCs/CS hydrogel) on tendon-to-bone healing after rotator cuff repair in rabbits. METHODS: TDSCs were isolated from the rotator cuff tissue of 3 adult New Zealand white rabbits by Henderson step-by-step enzymatic digestion method and identified by multidirectional differentiation and flow cytometry. The 3rd generation TDSCs were encapsulated in CS to construct TDSCs/CS hydrogel. The cell counting kit 8 (CCK-8) assay was used to detect the proliferation of TDSCs in the hydrogel after 1-5 days of culture in vitro, and cell compatibility of TDSCs/CS hydrogel was evaluated by using TDSCs alone as control. Another 36 adult New Zealand white rabbits were randomly divided into 3 groups ( n=12): rotator cuff repair group (control group), rotator cuff repair+CS hydrogel injection group (CS group), and rotator cuff repair+TDSCs/CS hydrogel injection group (TDSCs/CS group). After establishing the rotator cuff repair models, the corresponding hydrogel was injected into the tendon-to-bone interface in the CS group and TDSCs/CS group, and no other treatment was performed in the control group. The general condition of the animals was observed after operation. At 4 and 8 weeks, real-time quantitative PCR (qPCR) was used to detect the relative expressions of tendon forming related genes (tenomodulin, scleraxis), chondrogenesis related genes (aggrecan, sex determining region Y-related high mobility group-box gene 9), and osteogenesis related genes (alkaline phosphatase, Runt-related transcription factor 2) at the tendon-to-bone interface. At 8 weeks, HE and Masson staining were used to observe the histological changes, and the biomechanical test was used to evaluate the ultimate load and the failure site of the repaired rotator cuff to evaluate the tendon-to-bone healing and biomechanical properties. RESULTS: CCK-8 assay showed that the CS hydrogel could promote the proliferation of TDSCs ( P<0.05). qPCR results showed that the expressions of tendon-to-bone interface related genes were significantly higher in the TDSCs/CS group than in the CS group and control group at 4 and 8 weeks after operation ( P<0.05). Moreover, the expressions of tendon-to-bone interface related genes at 8 weeks after operation were significantly higher than those at 4 weeks after operation in the TDSCs/CS group ( P<0.05). Histological staining showed the clear cartilage tissue and dense and orderly collagen formation at the tendon-to-bone interface in the TDSCs/CS group. The results of semi-quantitative analysis showed that compared with the control group, the number of cells, the proportion of collagen fiber orientation, and the histological score in the TDSCs/CS group increased, the vascularity decreased, showing significant differences ( P<0.05); compared with the CS group, the proportion of collagen fiber orientation and the histological score in the TDSCs/CS group significantly increased ( P<0.05), while there was no significant difference in the number of cells and vascularity ( P>0.05). All samples in biomechanical testing failed at the repair site during the testing process. The ultimate load of the TDSCs/CS group was significantly higher than that of the control group ( P<0.05), but there was no significant difference compared to the CS group ( P>0.05). CONCLUSION TDSCs/CS hydrogel can induce cartilage regeneration to promote rotator cuff tendon-to-bone healing.
Rabbits ; Animals ; Rotator Cuff/surgery* ; Chitosan ; Hydrogels ; Rotator Cuff Injuries/surgery* ; Wound Healing ; Tendons/surgery* ; Collagen ; Stem Cells ; Biomechanical Phenomena

To present the clinical characteristics and the misdiagnosis rate of acute coronary syndrome manifested primarily as throat discomfort, we conducted a multicentric and retrospective study in the cardiology and otorhinolaryngology departments. Records of patients with primary complaint of throat discomfort, absence of chest pain at onset, and an ultimate diagnosis of acute coronary syndrome, as well as patients with pharyngitis (as controls) were collected from May 2015 to April 2016. The patients' main manifestations were compared. Logistic regression results showed that chest tightness, dyspnea, perspiring, and exertional throat symptoms were significantly associated with acute coronary syndrome, with odds ratios of 8.3 (95% CI 2.2-31.5), 10.9 (95% CI 1.8-66.9), 25.4 (95% CI 3.6-179.9), and 81.2 (95% CI 13.0-506.7). A total of 25 (56.82%) out of 44 acute coronary syndrome patients, who were first admitted to the otorhinolaryngology department, were misdiagnosed, with a 12% (3/25) mortality rate. Throat discomfort can be the principal manifestation of acute coronary syndrome. Such patients exhibit high misdiagnosis and mortality rates. Exertional throat symptoms, chest tightness, perspiring, and dyspnea were important indicators of acute coronary syndrome in patients whose main complaint was throat discomfort. The awareness of this condition will result in prompt diagnosis and reduce morbidity and mortality.
Acute Coronary Syndrome/etiology* ; Dyspnea/etiology* ; Humans ; Pharyngitis/diagnosis* ; Pharynx ; Retrospective Studies