A broken metal handle accompanied by femoral trunk fracture, which would shorten service life of handles. Therefore, it is necessary to judge whether the notch is the main reason for handle broken. Some literatures thought that the pores of sintered porous coated anatomic (PCA) porous layer produce the notch on the handle surface and the notches lead to the handle broken being incorrect. The Apex of the pore is taken for the bottom of the notch, expanding into a crack, and it should also not grow to the base-alloy, accordingly, the above conclusion is wrong. Some reports pointed out the notch, apex of the pore, will expand into the crack, but it is not associated with the broken handle. Under the sintering temperature, the grain boundary apertures be generated on the base metal surface, the aperture is expanded into the crack, which leads to handle broken in the forced area. However, neither theoretical basis, nor a case of corroboration, can prove exist of notch. Actually, the broken handle is caused by the sintering technology. The high temperature of sintering joining results in grain boundary aperture, when encounter the largest forced area and expand into crack, it will break the handle.

INTRODUCTION: General joining techniques are at low level, which produces some potential problems in porous layer of porous coated anatomic (PCA).LIMITATIONS: The problems in general joining techniques are caused by limitations of each technique, which could not be solved using advanced measures.APPLICATION: The activated diffusion brazing technology is an effective way. Its many advanced processes can solve those potential problems.CONCLUSION: The stress-shielding problem caused by PCA porous layer can be solved by using small metal balls in the same diameter in combination with the advanced activated diffusion brazing technology. Moreover, the high performance brazing metals by activated diffusion brazing technology is harmless for humans.

OBJECTIVE: Sintering of porous coated anatomic porous layer bonding technology remains controversial because of poor understanding to its essence.ESSENCE: Sintering is a technology that the bonding temperature exceeds 5 ℃ or higher than the base-alloy solids temperature of 1 230 ℃, resulting in base-alloy produce a series of serious problems, such as grain boundary racks, handle broken and so on.HAZARDS: In sintering temperature, the low melting point eutectlc phase and the brittle metal compounds flow out of the grain boundary to bond the small metal balls and the handle, which greatly reduces the fatigue strength. The grain boundary cracks formed and expanded ultimately leading to handle broken.DISCUSSION: The cause of a handle broken is neither notch nor metallurgical defects but sintering process, because high sintering temperature results in grain-boundary lacunas.CONCLUSION: Sintering is not suitable for connecting the force components. High sintering temperature produces grain-boundary lacunas which can expand into cracks and ultimately result in handle broken under some condition.

Objective To quantitative evaluate the myocardial microcirculation dysfunction in patients with end-stage renal disease (ESRD),and to provide the imaging characteristic for early detection myocardial dysfunction and microcirculation damage in the ESRD patients after dialysis therapy.Methods Sixty-seven patients with ESRD and 1 9 healthy subj ects were enrolled in our study, and the ESRD patients were divided into two groups including patients with preserved systolic function (n=51,EF≥50%)and patients with impaired systolic function (n=16,EF＜50%).The LV regional myocardial perfusion parameters were analyzed including upslope, time to maximum signal intensity (TTM)and max signal intensity (Max SI).Those continuous variables were compared using one-way analysis of variance (A N OVA )in all three groups.Results Compared with the controls and the ESRD patients with preserved EF,the ESRD patients with impaired EF had a significantly lower SV and markedly increased LV mass (all P＜0.001).For the fist-pass perfusion analysis,first-pass perfusion Max SI of all segments were significantly reduced in the ESRD patients with preserved/impaired EF compared with the normal subjects (all P＜0.05).Compared with the ESRD patients with preserved EF and controls,the ESRD patients with impaired EF had lower upslope in the basal segment (P＜0.05).And the ESRD patients with preserved/impaired EF had shorter TTM in the apical segment than that in normal controls (P＜0.01).Conclusion The CMR first-pass perfusion can detect the myocardial deformation and dysfunction in ESRD patients,the Max SI may be more valuable to early detect myocardial microcirculation dysfunction.

Diabetic cardiomyopathy is defined as abnormal structure and function of the heart in the setting of diabetes, which could eventually develop heart failure and leads to the death of the patients. Although blood glucose control and medications to heart failure show beneficial effects on this disease, there is currently no specific treatment for diabetic cardiomyopathy. Over the past few decades, the pathophysiology of diabetic cardiomyopathy has been extensively studied, and an increasing number of studies pinpoint that impaired mitochondrial energy metabolism is a key mediator as well as a therapeutic target. In this review, we summarize the latest research in the field of diabetic cardiomyopathy, focusing on mitochondrial damage and adaptation, altered energy substrates, and potential therapeutic targets. A better understanding of the mitochondrial energy metabolism in diabetic cardiomyopathy may help to gain more mechanistic insights and generate more precise mitochondria-oriented therapies to treat this disease.

Objective:To investigate the treatment strategy for pediatric humeral supracondylar fractures with callus formation and displacement neglected for over 1 week.Methods:A retrospective analysis was made of the clinical data of 36 children who had been treated at Department of Pediatric Orthopaedics, Medical Center, The Second Affiliated Hospital, Inner Mongolia Medical University from January 2011 to January 2021 for humeral supracondylar fractures with callus formation and displacement neglected for over 1 week. There were 22 boys and 14 girls, with an age of (6.7±2.7) years (from 2.3 to 12.8 years). All fractures were Gartland type Ⅲ. The patients were divided into 2 groups according to their treatment methods: a closed reduction and percutaneous pinning (CRPP) group of 15 patients subjected to the CRPP treatment only, and a leverage group of 21 patients subjected to CRPP assisted by the "lever technique" with posterior elbow Kirschner wire prying and pulling. The 2 groups were compared in terms of operation time, fluoroscopy frequency, quality of reduction, and recovery time for elbow range of motion; the elbow range of motion, visual analogue scale (VAS), Mayo elbow performance score (MEPS) and complications were assessed at the last follow-up.Results:The 2 groups were comparable because there was no significant difference between them in the general information before operation ( P>0.05). All patients were followed up for (26.2±16.3) months (from 6 to 96 months). All the fractures obtained acceptable reduction and clinical union 4 to 6 weeks after operation. The operation time [(28.2±6.8) min] and fluoroscopy frequency [(27.0±6.0) times] in the leverage group were significantly less than those in the CRPP group [(40.8±10.8) min and (43.3±11.4) times] ( P<0.05). The CRPP group was significantly better than the leverage group in the intraoperative Baumann angle (78.1°±1.6° versus 73.7°±4.1°), lateral capitellohumeral angle (58.3°±2.6° versus 49.6°±5.2°) and horizontal rotation rate (109.5%±3.0% versus 103.2%±4.9%) ( P<0.05). The intraoperative reduction in the CRPP group was significantly closer to the normal mean value than that in the leverage group ( P<0.05). There was no significant difference in the recovery time for elbow range of motion between the CRPP and the leverage groups ( P>0.05). At the last follow-up, the Baumann angle (75.4°±2.8°) and the lateral capitellohumeral angle (53.2°±3.6°) in the leverage group were still significantly better than those in the CRPP group (78.3°±1.5° and 57.5°±2.3°) ( P<0.05). However, there was no significant difference in the elbow range of motion, VAS, MEPS or incidence of complications between the 2 groups ( P>0.05). Conclusion:To treat humeral supracondylar fractures with callus formation and displacement neglected for over 1 week in children, CRPP assisted by the "lever technique" with posterior elbow Kirschner wire prying and pulling is an efficient and accurate method, because it can lead to more satisfactory reduction than CRPP only.

AIM:To explore the roles and associations of hepatocyte nuclear factor 4 alpha(HNF4A)and mu-protocadherin(MUCDHL)in the kidney of diabetic mice.METHODS:(1)A cohort of six 12-week-old db/m mice and six db/db mice were selected and maintained on a standard diet until 16 weeks.The protein levels of fibronectin(FN),collagen type III(Col-III),E-cadherin,α-smooth muscle actin(α-SMA),HNF4A,Snail and MUCDHL in renal tissues were scrutinized using Western blot.Immunohistochemical staining was conducted to observe the distribution and expres-sion of FN,HNF4A and MUCDHL.(2)Mouse renal tubular epithelial cells(mRTEC)were cultured in vitro and catego-rized into groups:normal glucose(NG)group,high glucose(HG)group,overexpression control groups(NG+vector and HG+vector),overexpression groups(NG+OE-MUCDHL,HG+OE-MUCDHL,NG+OE-HNF4A and HG+OE-HNF4A),knockdown control groups(NG+control and HG+control),and knockdown groups(NG+si-MUCDHL,HG+si-MUCDHL,NG+si-HNF4A and HG+si-HNF4A).The relevant protein levels were also detected by Western blot.RESULTS:(1)In db/db group,elevated body weight,blood glucose and urine albumin-to-creatinine ratio(UACR)indicated significant re-nal injury.Compared with db/m group,the mice in db/db group exhibited increased expression of FN,Col-III,α-SMA and Snail,and decreased expression of E-cadherin,HNF4A and MUCDHL.MUCDHL was predominantly expressed in the apical membrane of renal tubular epithelial cells,FN in the tubular mesenchyme,and HNF4A in the plasma and nu-cleus of renal tubular cells.(2)In HG group,there was an up-regulation in the expression of fibrosis-related proteins and a down-regulation in the expression of E-cadherin,HNF4A and MUCDHL compared with NG group.Overexpression of MUCDHL led to a decrease in the expression of FN,Col-III,α-SMA and Snail proteins,an increase in the expression of E-cadherin and MUCDHL proteins,and unaltered expression of HNF4A.Knockdown of MUCDHL resulted in a reversal of the aforementioned effects,with HNF4A expression remaining unaltered.Overexpression of HNF4A led to an increased ex-pression of MUCDHL,and the expression changes of the remaining indicators were consistent with the overexpression of MUCDHL.Knockdown of HNF4A reversed the aforementioned effects.MUCDHL may represent a downstream target gene of HNF4A.CONCLUSION:The diminished expression of HNF4A and MUCDHL in the renal tubules of diabetic mice implies their involvement in the progression of renal fibrosis in diabetic kidney disease(DKD).HNF4A may potentially impede the progression of renal fibrosis in DKD by up-regulating the expression of MUCDHL.