BACKGROUND:Previous studies of our research group have confirmed that the texture of porcine reticular dermis at lateral ventral part is softer and has more extensibility than other parts. Therefore, it may serve as the raw material of xenogenic aceluar dermal matrix. However, its comparison with human and rat reticular dermis has not been reported systematicaly in aspects of histomorphology and material characterization. OBJECTIVE:To compare the reticular dermis from the lateral region of porcine abdomen and rat dorsal part with the reticular dermis from human in histology, biomechanics, molecular structure, thermal stability and other properties. METHODS:The reticular dermis samples were taken from adult human, the lateral region of porcine abdomen, the back of rats, for gross observation. Paraffin sections were observed by hematoxylin and eosin staining and sirius red staining under a light microscopy. The relevant data of micrograph were measured by imagine analysis software. These samples were also vacuum-freezing dried and rehydrated, and then their mechanical properties were tested with a electronic tensile machine to calculate the Young’s modulus. Some vacuum-freezing dried samples were powdered and detected by Fourier transform infrared spectrometer and simultaneous thermal analyzer. RESULTS AND CONCLUSION:There were no differences in colagen fiber bundle diameter of the reticular dermis from adult human and the lateral region of porcine abdomen, but the reticular dermis from the back of rats was thinner than that from adult human (P < 0.01). The gap between the reticular layer of the dermis of the lateral region of porcine abdomen was lower than that from adult human (P < 0.0.1); however, there was no difference in the gap between the reticular layers of the dermis of the rat back and adult human (P=0.17). Colagen fibers of porcine reticular dermis were arranged tightly in disorder; the content of type I colagen and ratio of type I/III colagen were higher than those in the reticular dermis from adult human (P < 0.05), but the content of type III colagen was less than that in the reticular dermis from adult human (P < 0.05). Contents of type I and III colagen and their ratio were similar between the reticular dermis of rats and adult human (P > 0.05). There was no significant difference in the Young’s modulus of the three kinds of reticular dermises. Hydrogen bonds involved in the reticular dermal colagen molecules ranged as folows: rats > swine > human. Rat reticular dermis has better thermal stability than that of swine and adult human.

Objective To investigate the effects of echocardiography-guided pacemaker parameters optimization in order to enhance the efficacy of cardiac resynchronization therapy(CRT).Methods Seventeen patients with chronic heart failure received biventricular resynchronous pacing therapy.A-V delay and V-V delay was optimized under the guiding of spectral Doppler echocardiography and tissue Doppler imaging.Results The indices of heart function in all patients were significantly improved after the treatment.The NYHA class of the patients was improved from class Ⅲ～Ⅳ to class Ⅱ～Ⅲ.Since PAV/SAV was optimized to 130-180/100-150 ms,left ventricular filling time(LVFT) was increased from (354±147)ms to (420±112)ms,mitral reflux (MR) was decreased from (8.41±4.55)cm2 to (5.36±4.71)cm2.After VV delay was optimized to 4-40ms,standard deviation of time to regional peak systolic velocity (Ts-SD-12) was decreased from (48.4±17.9)ms to (30.2±18.6)ms,left ventricular outflow tract velocity time integral(VTI LVOT) was increased from (20.6±9.0)cm/s to (26.1±3.1)cm/s.Conclusions Echocardiography-guided optimization of the pacemaker parameters is necessary in order to enhance the efficacy of CRT.

Objective Toevaluatetheclinicaleffectofinterventionaltreatmentfordelayedhemorrhageinpatientsafterabdominal surgery.Methods Dataof76patients,undergoingangiographyduetodelayedpostoperativehemorrhage,wereanalyzedretrospectively. Theexclusioncriteriaincludedpositiveangiographywithoutembolizationorhaemorrhagecausedbyothercauses(urologicaland reproductivesystemdiseases).Basedonendovascularprocedures,thepatientsweredividedintoembolizedgroup (positiveangiography withembolization)andnon-embolizedgroup(negativeangiographywithoutembolization).Theoutcomesoftreatmentwerecompared betweentwogroupsandfactorsassociatedwithrebleedingwerealsoanalyzed.Results Angiogramswerepositivein70% (53/76)of patients,andintravascularembolizationswereperformed.Intheembolizationgroup,technicalsuccessrateandclinicalsuccessrate were98.1%(52/53)and71.7%(38/53),respectively.Noseverecomplications,suchasgastrointestinalorhepaticischemicnecrosis wereobservedinallpatients.Therebleedingrateswere28.3%and52.2%intheembolizationgroupandthenon-embolizationgroup, respectively(P＝0.046).Multivariateanalysisshowedthatuseofvasopressoragentsbeforesurgerywasanindependentriskfactor forrebleeding (P＝0.022).Conclusion Intravascularinterventionaltherapyisasafeandeffectivemethodfordelayedhemorrhageafter abdominalsurgery.Useofvasopressoragentsbeforesurgerymayincreasetheriskofpostoperativerebleeding.

Background: and Purpose Previous studies suggested increased visit-to-visit variability of total cholesterol (TC) is associated with stroke. This study aimed to investigate the associations of various lipids measurements variability and the risk of stroke and stroke type (ischemic and hemorrhagic stroke). Methods: Fifty-one thousand six hundred twenty participants in the Kailuan Study without history of myocardial infarction, stroke, and cancer who underwent three health examinations during 2006 to 2010 were followed for incident stroke. Variability in TC, triglycerides, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) measurements were measured using the coefficient of variation (CV), standard deviation (SD), variability independent of the mean (VIM), and average real variability (ARV). Results: During a median of 6.04 years of follow-up, 1,189 incident stroke (1,036 ischemic and 160 hemorrhagic stroke) occurred. In the multivariable-adjusted model, the hazard ratio (HR) comparing participants in the highest versus lowest quartile of CV of HDL-C were 1.21 (95% confidence interval [CI], 1.02 to 1.45; P for trend=0.013) for ischemic stroke. The highest quartile of CV of LDL-C was associated with 2.17-fold risk of hemorrhagic stroke (HR, 2.17; 95% CI, 1.25 to 3.75; P for trend=0.002) compared with the lowest quartile. We did not observe any significant association between TC and triglycerides variability with any of stroke. Consistent results were obtained when calculating variability index using SD, VIM, or ARV. Conclusions These findings suggest the high visit-to-visit HDL-C and LDL-C variability were associated with an increased incidence of ischemic and hemorrhagic stroke, respectively.