顺铂聚乳酸微球的药物释放特性及肝动脉栓塞研究

对顺铂聚乳酸微球进行了体外药物释放和家犬肝动脉栓塞研究。该微球粒径范围为50～200μm,平均粒径为115.76±35.94μm,顺铂含量为37.16%(W/W);体外药物释放机制符合Higuchi方程;肝动脉栓塞后8h,肝组织顺铂浓度高达21.55±12.18μg/g,明显高于肝动脉灌注顺铂组:3.16±0.09μg/g(P<0.05);肝动脉栓塞组的顺铂血浓峰值、各取血点浓度及曲线下面积AUC皆低于肝动脉灌注顺铂组。可望达到提高栓塞部位的药物疗效,降低全身毒副反应的作用。     

Neuronal activity evoked by chronically implanted intracortical microelectrodes

The averaged evoked compound action potentials (AECAPs) were recorded from the ipsilateral pyramidal tract of awake, unrestrained cats before, during, and after continuous electrical stimulation of the cerebral cortex via chronically implanted activated iridium or platinum-30% iridium (Pt30%Ir) microelectrodes. After stimulating 24 h at 20 pulses per second (pps), using charge-balanced, 200-microseconds pulse pairs of 40 to 80 microA (400 to 800 microC/cm2, 8 to 16 nC/phase (ph), 2 to 4 A/cm2), there was a transient elevation of the threshold of the early (direct) and of the alte (transynaptic) components of the AECAP. After cessation of continuous stimulation at 80 microA, the threshold of the early component of the AECAP remained elevated for as long as 24 h and the late component as long as 4 days, indicating significant but reversible depression of the electrical excitability of cortical neurons close to the microelectrodes. In three cats stimulated 23 h/day for 1 week, the AECAP also recovered to their prestimulus threshold. In contrast, pulsing for 24 h at 320 microA (3200 microC/cm2, 64 nC/ph, 16 A/cm2) produced marked elevation of the threshold of the AECAPs which was not reversed by 7 to 12 days after termination of intracortical stimulation. The electrical excitability of neurons adjacent to (unpulsed) microelectrodes 2 mm from the pulsed electrode was not affected. The observations reported here, in conjunction with the histologic results reported in the companion paper, indicate that both the Pt30%Ir and the iridium microelectrodes can be operated safely at currents to at least 80 microA, charge/ph of 16 A/cm2, and a charge density of 800 microC/cm2 X ph. However, on the basis of the electrophysiologic criteria, both types appear to be unsafe when pulsed at 320 microA (64 nC/ph, 3200 microC/cm2 X ph, 16 A/cm2).     

2-甲酰(乙酰)取代喹啉缩氨基硫脲的合成

缩氨基硫脲类化合物有抗肿瘤、抗病毒和抗菌等多种药理活性。Barret等首次报道了乙二醛二缩氨基硫脲(Ⅰ)的抗疟活性。Klayman等研究了缩     

Retrograde coronary sinus perfusion

"Redo" operations for coronary artery disease have become commonplace. One of the major complications that occurs is perioperative infarction due to embolization of atheromatous material from diseased veins into the distal coronary arteries. Because of this, we began using retrograde coronary sinus perfusion (RCSP) for delivery of cardioplegia to prevent the embolization of grumous material. It is our belief that retrograde flow through the coronary arteries is an effective preventive measure. In addition, RCSP is a simple method of delivery in redo operations such as aortic valve replacement where the majority of coronary flow is through patent vein grafts. Sixty-five of approximately 3,100 patients in our practice in the past three years underwent a cardiac operation in which RCSP was used for cardioplegia delivery. Ventricular function in all patients was well preserved, and all survived. There were no complications associated with the use of this method.     

Sequencing of the alpha-synuclein gene in a large series of cases of familial Parkinson's disease fails to reveal any further mutations. The European Consortium on Genetic Susceptibility in Parkinson's Disease (GSPD)

A mutation in exon 4 of the human alpha-synuclein gene was reported recently in four families with autosomal dominant Parkinson's disease (PD). In order to examine whether mutations in this exon or elsewhere in the gene are common in familial PD, all seven exons of the alpha- synuclein gene were amplified by PCR from index cases of 30 European and American Caucasian kindreds affected with autosomal dominant PD. Each product was sequenced directly and examined for mutations in the open reading frame. No mutations were found in any of the samples examined. We conclude that the A53T change described in the alpha- synuclein gene is a rare cause of PD or may even be a rare variant. Mutations in the regulatory or intronic regions of the gene were not excluded by this study.      

Positive microscopic surgical margins: Is there an association with survival in resected small gastrointestinal stromal tumors?

BackgroundFew studies evaluate the relationships between surgical approach, histologic margin, and overall survival in gastrointestinal stromal tumor. We test the hypothesis that margin positive resection is associated with compromised overall survival.MethodsWe queried the National Cancer Data Base to identify patients undergoing resections for gastrointestinal stromal tumors ≤3 cm in size between 2010 and 2015. Multivariable logistic regression was used to identify factors associated with positive microscopic margins on final pathology. Cox proportional hazard methods were used to evaluate factors associated with overall survival.Results2064 patients met inclusion criteria; 135 (6.5%) had a microscopically positive surgical margin. On multivariable regression, minimally invasive approach was not associated with risk of a positive margin (OR 1.06 95% CI [0.71, 1.59]). On Cox analysis, positive margin status was not associated with OS (R1: 1.03, CI [0.46–2.31], reference R0).ConclusionsPositive microscopic surgical margins are not associated with compromised overall survival in patients undergoing resection of small gastrointestinal stromal tumors. Minimally invasive surgical approaches do not compromise oncologic outcomes in these cases.     

The importance of the margin of resection and external radiation in non-lipomatous retroperitoneal sarcoma

BackgroundPrior studies evaluating the impact of adjuvant or neoadjuvant radiation on clinical outcomes of patients with non-lipomatous retroperitoneal sarcoma have been underpowered.MethodsWe queried the National Cancer Database to identify patients undergoing surgical resection of retroperitoneal sarcoma with non-lipomatous histology from 2004 to 2016. Multivariable logistic regression and Cox proportional hazards modelling with patients stratified by tumor size were used to identify factors associated with overall survival.Results3,394 patients met inclusion criteria. 592 had small (<5 cm), 1,186 had intermediate (5–10 cm), and 1,616 had large (>10 cm) tumors. Use of either neoadjuvant or adjuvant radiotherapy was associated with improved survival for patients with intermediate (neoadjuvant HR 0.67, CI [0.46, 0.98]; adjuvant HR 0.61, CI [0.50, 0.76]) and large (neoadjuvant HR 0.50, CI [0.37, 0.68]; adjuvant HR 0.56, CI [0.47, 0.69]) tumors, while adjuvant radiation therapy was associated with a survival benefit for small-sized tumors (HR 0.67, CI [0.46, 0.99]).ConclusionsRadiation therapy is associated with an overall survival benefit in patients presenting undergoing resection of non-lipomatous retroperitoneal sarcoma.     

ACFAS Clinical Consensus Statement: Acute Achilles Tendon Pathology

Injuries to the Achilles tendon are a challenge to the foot and ankle surgeon. In recent years, research has led to a relative change in the way that many surgeons view acute Achilles tendon rupture. In an effort to fully evaluate these trends, as well as to evaluate all aspects of care for acute Achilles tendon rupture, the American College of Foot and Ankle Surgeons convened a panel of experts to create a clinical consensus statement to address selected aspects of care of the acute Achilles tendon injury.     

Cardiac allograft vasculopathy: the green lane hospital experience 1987-1998

AIMS: To determine the prevalence of cardiac allograft vasculopathy in heart transplant recipients at Green Lane Hospital and to examine potential risk factors for vasculopathy. METHODS: We retrospectively reviewed the coronary angiograms of all cardiac transplant recipients. Angiography was usually performed one, two and five years after operation. The diagnosis of allograft vasculopathy was made if there was any evidence of coronary artery disease. Patients' medical records were reviewed for potential risk factors. RESULTS: Ninety-one patients underwent cardiac transplantation between December 1987 and March 1998. One year survival was 87%. Angiographic evidence of coronary disease was present in 30 patients and in three patients coronary lesions were first identified at post mortem. Vasculopathy was present in 25%, 35% and 61% of patients at one two and five years following transplant. Donor-acquired lesions could not be excluded as few patients had immediate postoperative angiograms for comparison. Five late deaths have been due to vasculopathy. Recipient age, race, donor age and ischaemic time were similar for those with and without vasculopathy. Frequency or severity of acute rejection episodes, cytomegalovirus infection, lipid profiles, diabetes and hypertension were not significantly different in patients with vasculopathy. CONCLUSION: Cardiac allograft vasculopathy is a common finding after heart transplantation. No definite risk factors were identified in this patient group.