Objective To evaluate the effect of hydromorphone postconditioning on the electrophysiological stability during ischemia-reperfusion (I/R) in isolated rat hearts.Methods Healthy adult male Sprague-Dawley rats,aged 2-3 months,weighing 280-360 g,were heparinized and anesthetized with pentobarbital sodium.Their hearts were excised and perfused in a Langendorff apparatus with K-H solution saturated with 95％ O2-5％ CO2 at 37 ℃.Twenty-four Langendorff-perfused hearts were divided into 3 groups (n =8 each) using a random number table:control group (group C),I/R group and hydromorphone postconditioning group (group HM).The isolated hearts were subjected to 60 min ischemia followed by 60 min reperfusion to establish the model of isolated heart I/R injury.The isolated hearts were perfused with K-H solution containing 4.1 ng/ml hydromorphone for 10 min starting from onset of reperfusion in group HM.Heart rate,electrocardiogram,coronary flow,and monophasic action potential amplitude,in the left ventricular endocardium,mid-myocardium and epicardium the maximal increase rate (Vmax) at the 0 phase,and monophasic action potential duration at 50％ and 90％ repolarization (MAPD50 and MAPD90,respectively) were recorded at 20 min of stabilization (T0) and 10,25,40 and 60 min of reperfusion (T1-4).The transmural dispersion of repolarization (TDR) was calculated,and the time for restoratiou of spontaneous heart beat was recorded.Results There was no significant difference in the heart rate,coronary flow or monophasic action potential amplitude between the three groups (P＞0.05).Compared with group C,V in the epieardium was significantly decreased,MAPD50 and MAPD90 in the three transmural layers were prolonged,and TDR was prolonged in group I/R (P＜0.05).Compared with group I/R,the time for restoration of spontaneous heart beat,MAPD50 in the endoeardium and mid-myocardium,and MAPD90 and TDR in the endocardium were significantly shortened (P＜0.05),and no significant change was found in V in group HM (P＞0.05).Conclusion Hydromorphone postconditioning is helpful in maintaining the electrophysiological stability during I/R in isolated rat hearts.

Objective To evaluate the role of δ-opioid receptors in hydromorphone postcondition-ing-induced maintenance of electrophysiological stability during ischemia-reperfusion(I∕R)in isolated rat hearts. Methods Healthy male Sprague-Dawley rats, aged 2-3 months, weighing 280-360 g, were used in this study. The animals were anesthetized with intraperitoneal pentobarbital 60 mg∕kg. Their hearts were immediately removed and perfused in a Langendorff apparatus. Thirty-two isolated hearts were divided into 4 groups after successful preparation of Langendorff perfusion model(n=8 each)using a random number ta-ble: control group(group C), group I∕R, hydromorphone postconditioning group(group HP)and hydro-morphone plus δ-opioid receptor antagonist naltridole postconditioning group(group HNP). In HP and HNP groups, the hearts were perfused for 10 min with K-H solution containing 41 ng∕ml hydromorphone and 41 ng∕ml hydromorphone plus 5 μmol∕L naltridole, respectively, and then with K-H solution for 50 min. At 20 min of stabilization(T0)and 10, 25 and 60 min of reperfusion(T1-2), heart rate(HR), monophasic action potential(MAP)duration at 90% repolarization(MAPD90)of the two layers(endocar-dium, epicardium)of the anterior left ventricular wall were recorded. Transmural dispersion of repolariza-tion(TDR)was calculated. The development of arrhythmia, time for restoration of spontaneous heart beat and duration of arrhythmia were recorded during the period of reperfusion. Results Compared with group C, MAPD90of endocardium at T1-2and MAPD90of epicardium at T1were significantly prolonged in I∕R and HP groups, HR was significantly decreased at T2-3, MAPD90of endocardium and epicardium was prolonged at T1-3in group HNP, TDR was significantly enlarged at T1in group I∕R and at T2in group HNP, and TDR was decreased at T3in group HP(P<005). Compared with group I∕R, no significant change was found in arrhythmia score(P>005), the time for restoration of spontaneous heart beat was significantly shortened, and TDR was decreased at T1in HP and HNP groups, duration of arrhythmia was significantly shortened, and MAPD90of endocardium was shortened at T1in group HP, and HR was significantly decreased at T2-3, MAPD90of endocardium and epicardium was prolonged at T1-3, and TDR was decreased at T2-3in group HNP(P<005). Compared with group HP, no significant change was found in time for restoration of spon-taneous heart beat, duration of arrhythmia or arrhythmia score(P>005), HR was significantly decreased at T2-3, MAPD90of endocardium and epicardium was prolonged at T1-3, and TDR was increased at T3in group HNP(P<005). Conclusion The mechanism underlying hydromorphone postconditioning-induced maintenance of electrophysiological stability during I∕R is related to activating δ-opioid receptors in isolated rat hearts.

Objective:To investigate the characteristics of primary catheter malposition (PCM) following totally implantable venous access port (TIVAP) implantation via the internal jugular vein (IJV) and management strategies.Methods:Clinical data of 587 consecutive breast cancer patients undergoing TIVAP implantation via the IJV performed by single team at the Department of Breast Surgery, the First Affiliated Hospital of Zhengzhou University from Aug 2017 to Aug 2022 was retrospectively analyzed.Results:A total of 593 TIVAP were implanted and PCM was found in 18 cases (3.0%). Four hundred and twenty five TIVAP were implanted via the right IJV with one PCM case (0.2%). One hundred and sixty eight TIVAP implantations were performed via the left IJV and PCM occurred in 17 cases (10.1%). The interventional management with a pigtail catheter was performed as a first-line strategy in 11 of the 18 PCM cases, with a success in 10 cases and failure in one. Three cases were successfully managed with the digital subtraction angiography (DSA)-guided open approach. Four cases underwent blind open procedure firstly and 2 suffered a failure.Conclusions:A higher incidence of PCM is found in TIVAP implantations via the left IJV than the right one. The interventional management with a pigtail catheter or the DSA-guided open procedure proves to be feasible for the correction of PCM.

Objectives:To explore the microanatomy and functional MRI(fMRI) of arcuate fasciculus(AF) and superior longitudinal fasciculus(SLF),and to analyze their functions.Methods:Ten normal adult cadaveric head specimens (20 cerebral hemispheres) were fixed with 10% methanal at the Translational Research Institute for Neurological Disorders of the Wannan Medical College from February to December 2022.The Klingler fiber dissection technique was utilized to perform white matter fiber dissection,with a magnification ranging from 6 to 40.The study focused on the microanatomical structures of the AF and SLF,aiming to explore their relationships with deep brain fibers.Furthermore, six healthy adult volunteers who underwent fMRI of the brain were included.The collected diffusion tensor imaging (DTI) data were processed and integrated with the microanatomical findings for a comprehensive analysis.Results:After removing the gray matter of the cerebral cortex,the superficial U fibers were exposed.The long association fibers that beneath the U fibers were the AF and SLF,which were the main long association fibers in the superficial layers of the brain.The AF could be divided into dorsal and ventral parts,while the SLF could be divided into Ⅰ,Ⅱ,and Ⅲ.SLF Ⅰ lied within the upper bank of the cingulate sulcus,travels medial to the callosal sulcus.The SLF Ⅱ,Ⅲ,and the AF were located on the lateral surface of the brain.By removing the gray matter of the insular cortex and the extreme capsule,exposing the external capsule and claustrum.Subsequently,the AF and SLF Ⅱ,Ⅲ were dissected,revealing the corona radiata and sagittal stratum,along with other deep brain fibers.During the dissection,it was observed that there was a close connection between the AF,SLF Ⅱ,and the deep brain fibers.Furthermore,in the regions above the lateral fissure of the cerebral hemisphere,there was no direct connection of long association fibers between the gray matter cortex and the deep U fibers in the coronal plane.These findings were further supported by DTI studies.Conclusions:The AF and SLF are the major long association fibers that located in the superficial layers of the brain,and closely connect to the gray matter cortex and U fibers,even closely relate with deep brain fibers.In the regions above the lateral fissure of the hemisphere,only the AF and SLF Ⅱ and Ⅲ serve as superficial long association fibers in the anterior-posterior direction.These fibers are likely involved in the transmission of brain functional information between the top and bottom gray matter cortex in the coronal plane above the lateral fissure.

Objectives:To explore the microanatomy and functional MRI(fMRI) of arcuate fasciculus(AF) and superior longitudinal fasciculus(SLF),and to analyze their functions.Methods:Ten normal adult cadaveric head specimens (20 cerebral hemispheres) were fixed with 10% methanal at the Translational Research Institute for Neurological Disorders of the Wannan Medical College from February to December 2022.The Klingler fiber dissection technique was utilized to perform white matter fiber dissection,with a magnification ranging from 6 to 40.The study focused on the microanatomical structures of the AF and SLF,aiming to explore their relationships with deep brain fibers.Furthermore, six healthy adult volunteers who underwent fMRI of the brain were included.The collected diffusion tensor imaging (DTI) data were processed and integrated with the microanatomical findings for a comprehensive analysis.Results:After removing the gray matter of the cerebral cortex,the superficial U fibers were exposed.The long association fibers that beneath the U fibers were the AF and SLF,which were the main long association fibers in the superficial layers of the brain.The AF could be divided into dorsal and ventral parts,while the SLF could be divided into Ⅰ,Ⅱ,and Ⅲ.SLF Ⅰ lied within the upper bank of the cingulate sulcus,travels medial to the callosal sulcus.The SLF Ⅱ,Ⅲ,and the AF were located on the lateral surface of the brain.By removing the gray matter of the insular cortex and the extreme capsule,exposing the external capsule and claustrum.Subsequently,the AF and SLF Ⅱ,Ⅲ were dissected,revealing the corona radiata and sagittal stratum,along with other deep brain fibers.During the dissection,it was observed that there was a close connection between the AF,SLF Ⅱ,and the deep brain fibers.Furthermore,in the regions above the lateral fissure of the cerebral hemisphere,there was no direct connection of long association fibers between the gray matter cortex and the deep U fibers in the coronal plane.These findings were further supported by DTI studies.Conclusions:The AF and SLF are the major long association fibers that located in the superficial layers of the brain,and closely connect to the gray matter cortex and U fibers,even closely relate with deep brain fibers.In the regions above the lateral fissure of the hemisphere,only the AF and SLF Ⅱ and Ⅲ serve as superficial long association fibers in the anterior-posterior direction.These fibers are likely involved in the transmission of brain functional information between the top and bottom gray matter cortex in the coronal plane above the lateral fissure.