Genetic characterization of a mumps virus isolate during passaging in the amniotic cavity of embryonated chicken eggs

The aim of this study was the molecular characterization of a historical mumps isolate (an alleged individual sample). After RNA extraction and cDNA synthesis, selective nested PCR amplification with specific primers, automated DNA sequencing and RFLP analyses were performed. The relative ratios of the detected virus sequences were determined by GeneScan electrophoresis. Phylogenetic tree based on the 316 nucleotide region of the SH gene of the mumps virus was generated by the neighbor-joining method. Results obtained by the described molecular approach show: (a) there are two mumps virus variants, A and B, detected in the fourth passage of wild type virus in the amniotic cavity of embryonated chicken eggs (ECE); (b) variants A and B belong to different genotypes; (c) variants A and B differ in the HN and NP genes which code for amino acid sequences comprising immunogenic epitopes; (d) variant B contains one or more minor variants. We discuss whether the observed differences between the two variants are a consequence of natural heterogeneity or of laboratory contamination in the early passages.     

Diadenosine 5',5'-p1,p4-tetraphosphate deficiency in blood platelets of the Chediak-Higashi syndrome

Diadenosine tetraphosphate (AP4A) is an unusual nucleotide found in a variety of cells, including platelets. It has been suggested that platelet AP4A is stored in the dense granules and is metabolically inactive. We have studied the AP4A content of blood platelets in two patients and three cattle with Chediak-Higashi syndrome (CHS), a hereditary platelet defect with dense granule deficiency. Acid-soluble extractions of whole blood and platelets were neutralized. The adenosine triphosphate (ATP) level was measured by luminescence technique. To measure the AP4A content, the neutralized extract was treated with phosphomonoesterase for removal of ATP. The AP4A content was then measured by coupling the phosphodiesterase and luciferase reaction. The AP4A content was 0.43 nmol/mg protein for normal human platelets and 0.004 nmol/mg protein for CHS platelets. The ATP/AP4A ratio was 67 for normal and 3,023 for CHS platelets. The whole blood AP4A was reduced by 89% in CHS patients who had only a slight decrease in ATP level (26% reduction). Similarly, bovine platelets with CHS showed a marked decrease of AP4A content and a moderate reduction of the ATP level. The platelet ATP/AP4A ratio was 351 and 3,133 for normal and CHS cattle, respectively. Results demonstrate a marked reduction of AP4A in CHS platelets and suggest that AP4A may be a useful marker for the measurement of dense granule content in platelets.     

Cervical neural space narrowing during simulated rear crashes with anti-whiplash systems

Purpose  

Chronic radicular symptoms have been documented in whiplash patients, potentially caused by cervical neural tissue compression during an automobile rear crash. Our goals were to determine neural space narrowing of the lower cervical spine during simulated rear crashes with whiplash protection system (WHIPS) and active head restraint (AHR) and to compare these data to those obtained with no head restraint (NHR). We extrapolated our results to determine the potential for cord, ganglion, and nerve root compression.     

Vascular complications after 725 kidney transplantations during 3 decades

Among 725 renal transplantations, the most common vascular complication was arterial stenosis, which was observed in 23 patients (3.17%). The majority of 20 (6.49%) arterial stenoses appeared in our initial experiences when we routinely used end-to-end renal graft to internal iliac artery anastomoses. A significant reduction in this incidence (0.72%) was achieved by introducing end-to-side anastomoses of the renal graft artery to the external or common iliac arteries. Intractable hypertension or impaired renal function in 14 patients (60.87%) with arterial stenosis demanded treatment. Patch angioplasty was more successful than other methods. The limited possibilities of conservative treatment of arterial hypertension at that time were the main reason for this frequent surgical repair. Among other vascular complications, the most serious were 12 episodes of arterial bleeding in 10 patients. Five kidneys were lost because of ruptured arterial anastomoses. In 6 patients, the common or external iliac artery was ligated as to achieve hemostasis with acute arterial insufficiency of the lower extremity in 4 patients. One patient required leg amputation, whereas 2 underwent extra-anatomic bypass procedures and 1 died because of hepatic failure. The majority of vascular complications occurred in the initial period of our transplantation practice. However, in spite of progress in diagnostic and treatment options, vascular complications may cause considerable clinical problems.     

钾通道开放剂KRN4884对猪冠状微血管内皮源性超极化因子介导松弛的影响

目的高钾溶液能够减少血管内皮源性超极化因子(EDHF)介导的舒张,本研究拟观察ATP敏感的钾通道开放剂KRN4884(ATP-SPCOs)能否影响经高钾溶液孵育后的猪冠状微动脉中EDHF介导的舒张.方法将猪冠状微动脉血管段(200～450 μm)固定于肌张力描记装置的器官小室中,37℃下以高钾溶液(K+20 mmol/L)孵育1 h后,用血栓素类似物(U46619)收缩血管,在环氧化酶抑制剂吲哚美辛(INDO),一氧化氮合成酶抑制剂NG-硝基-L-精氨酸(L-NNA)以及NO捕捉剂氧合血红蛋白(HbO)存在的条件下,观察缓激肽(BK,Ⅰ组)诱导的EDHF介导的舒张功能,以及将不同浓度的KRN4884加入高钾溶液中对血管进行孵育后(II-1,2,3组),这种功能的变化情况.结果经高钾溶液呼育后,BK诱导EDHF介导的最大舒张明显被减少,(72.5±7.8)%比(41.6±10.6)%;P＜0.05.KRN4884在浓度为-4log mol/L和-7log mol/L时降低U46619诱发的血管收缩力,(1.7±0.3)比(7.1±1.9)mN.P＜0.05;3.2±1.6比7.8±1.7mN,P＜0.05;在浓度为-8log mol/L(5.8±1.7)比(7.1±1.5)mN,n=11;P＞0 05时,其降低血管收缩力的作用不明显.用KRN4884(-8log mol/L)加入高钾溶液可部分恢复这种被减少的EDHF的功能(59.9±5.6)%比(77.2±5.3)%,P＜0.008.结论在猪冠状微动脉,高钾溶液可以损伤EDHF介导的微血管舒张功能,而KRN4884可能部分恢复这种被损伤的功能.