Zero-Order Release Formulation of Oxprenolol Hydrochloride with Swelling and Erosion Control

Zero-order release of oxprenolol hydrochloride was obtained by controlling the swelling and erosion of the matrix. This formulation involves only mixing of drug, hydroxypropylmethylcellulose (HPMC), and sodium carboxymethylcellulose (Na CMC) at the ratio of 1:0.4:1.6, respectively, and compressing the mixture directly into tablets. The in vitro release pattern from this optimized matrix tablet was reproducible. Accelerated stability studies revealed that the optimized formulation remains stable for an approximately 2-year shelf life. This sustained-release (SR) tablet was evaluated in dogs, and for comparison a conventional (CV) formulation was also given at the same dose level. Plasma oxprenolol levels were monitored by a sensitive and specific high-performance liquid chromatographic (HPLC) method. Significant differences in the pharmacokinetic parameters, i.e., lower C _max, higher values of t _max, MRT, AUC, and plasma concentration at 24 hr, and nearly constant plasma levels over 12 hr, indicated that the SR matrix tablet is superior to the CV rapid-releasing formulation. The in vitro release parameters and in vivo pharmacokinetics correlated well.     

Inadequate dietary magnesium intake increases atherosclerotic plaque development in rabbits

Epidemiological studies have shown dietary magnesium (Mg) intake and serum Mg levels to be inversely correlated with the development of atherosclerosis. We hypothesized that low levels of Mg would promote atherosclerotic plaque development in rabbits. New Zealand white rabbits (4 months old, n = 22) were fed an atherogenic diet containing 0.12% (−Mg), 0.27% (control), or 0.43% (+Mg) Mg for 8 weeks. Blood samples were obtained at baseline, 2, 4, 6, and 8 weeks and were assayed for total cholesterol, high-density lipoprotein (HDL), non-HDL, triglycerides (TG), C-reactive protein, serum Mg, and erythrocyte Mg. Aortas from −Mg had significantly more plaque, with an intima thickness 42% greater than control and 36% greater than +Mg. Serum cholesterol levels rose over time, and at 8 weeks, −Mg had the highest and +Mg the lowest total and non-HDL cholesterol and TG levels, although these results did not reach significance. Over time, serum Mg levels increased, and erythrocyte Mg levels decreased. C-reactive protein significantly increased in all groups at 4 and 6 weeks but returned to baseline levels by 8 weeks. This study supports the hypothesis that inadequate intake of Mg results in an increase in atherosclerotic plaque development in rabbits.     

儿童陈旧性孟氏骨折的手术治疗

目的:通过研究火器伤所致骨折患者的治疗及预后情况,探讨如何选择合理方法对其进行及时有效的治疗。方法:对25例火器伤所致骨折患者的治疗及预后情况进行回顾性总结分析,其中男18例,女7例;平均年龄36.2岁。骨折的部位为股骨骨折9例,胫骨骨折7例,肱骨骨折2例,骨盆骨折2例,锁骨骨折1例,椎体骨折1例,尺、桡骨骨折1例,髋关节骨折1例与膝关节损伤1例。骨折类型为未移位1例,移位2例,粉碎性10例,粉碎且移位6例,骨缺损6例。19例接受了骨科手术治疗,其他6例接受了清创治疗。10例采用外固定架固定,7例行内固定,4例行管形石膏固定,2例骨盆与髋臼骨折采用牵引治疗,2例锁骨骨折应用锁骨带治疗。结果:25例患者获得了平均4.2年的随访,18例骨折Ⅰ期愈合,6例需后期手术促进骨折愈合,1例截肢。有5例需要后期手术覆盖创面。大的并发症包括2例骨不连,4例延迟愈合,3例周围神经功能受损。结论:骨折固定方法的选择与骨移植是治疗火器伤所致的骨折与骨缺损的一项很有效的方法。     

Postembryonic development of tapeworms — source of novel phylogenetic characters for analysis of cestode evolution: comparative TEM studies

Summary Ultrastructural features of juvenile cestodes (metacestodes) can provide useful characters for phylogenetic and evolutionary analyses. Until now, however, they have been relatively little utilised (Beveridge 2001, Chervy 2002). The postembryonic development and structure of fully formed metacestodes were examined in two cyclophyllideans: Taenia parva Baer, 1926 (Taeniidae); and Sobolevitaenia verulamii (Mettrick, 1958) Korniushin, 1972 (Dilepididae). In T. parva, three developmental stages were recognized: (1) an early stage of exogenous budding at the surface of the central vesicle; (2) a stage of polycephalic cyst development accompanied by segmentation of the growing metacestode strobila and an obvious decrease in the size of the central vesicle; (3) a fully formed metacestode of the strobilocercus type with 14–24 invaginated scoleces. The tegument, scolex, subtegumental musculature of the strobilar segments, protonephridial system, calcareous corpuscles and medullary parenchyma of larvae exhibit general similarity to the same structures in adults at both LM and TEM levels. The morphogenesis of the metacestode of T. parva is compared with that of polycephalic metacestodes of other Taenia spp. (T. krepkogorski, T. twitchelli and T. endothoracica) and with other asexually multiplying metacestodes (Mesocestoides vogae, hymenolepidids and dilepidids). In S. verulamii, the body of the cysticercoid with invaginated scolex armed with a double crown of rostellar hooks was completely surrounded by the cercomer, which appears to be separated from the cyst and scolex. The surface of the suckers is covered with a thick layer of glycocalyx. Five cell types were distinguished in the sections: (1) perikarya of metacestode tegument; (2) glycolgen-storing parenchymal cells; (3) glandular-type cells with large, electron-dense secretory-like granules; (4) flame cells; and (5) calcareous corpuscle-forming cells. The surface of the cercomer is covered by elongated microvilli, which evidently differ from characteristic microtriches covering all other parts of the metacestode surface. The ultrastructure of S. verulamii evidently differs from that of the other dilepidid cestode examined to date, Lateriporus geographicus, the cyst wall of which more resembles cysticercoids of Hymenolepididae than those of Dilepididae. Concluding remarks: Ultrastructural studies on metacestodes have considerable promise for providing important new characters for phylogenetic analysis. New TEM data on a great variety of cestode species are urgently needed. Until now, this field has not been exploited in a systematic fashion. Until more comprehensive studies become available, the current data are not yet amenable to analysis.     

Lucian Leape on Patient Safety in U.S. Hospitals

PURPOSE: To describe and discuss the status of patient safety in U.S. hospitals. METHODS: Personal interview. This report is part of a series of discussions with a leading expert on patient safety. FINDINGS AND CONCLUSIONS: Some improvements have been made in the past 10 years. But changes have not been adequate. Continuing barriers include the punitive environment in hospitals, physicians' denial of the scope of the problem, lack of national leadership, and lack of systems thinking.     

援外针灸临床综述(二)

介绍我国援外医疗队在 3 6个国家以 17种治疗方法为主治疗 40多种病的概况。     

应重视口腔颌面部恶性肿瘤的综合序列治疗

口腔颌面部恶性肿瘤约占全身恶性肿瘤的3％，虽然所占比例不高，但l大l其解剖部位特殊．涉及美观和重要的生理功能，冈此对患者机体和心理的影响不容忽视。早期（Ⅰ、Ⅱ期）口腔颌面部恶性肿瘤无论采用手术和（或）放射治疗，均能取得良好效果。但遗憾的是，大多数患者就诊时，已属局部一区域晚期（Ⅲ、Ⅳ期）。由于受到局部解剖和维持功能的限制，单纯通过扩大手术切除范围和改进现有手术技术，除能改善患者生存质量外，已无法提高此类患者的生存率，延长其生存时间。     

Serum IgA and IgG functional antibodies and their subclasses to Streptococcus pneumoniae capsular antigen found in two aged‐matched cohorts of children with and without otitis media with effusion

Serum IgA and IgG functional antibodies and their subclasses to Streptococcus pneumoniae capsular antigen found in two aged‐matched cohorts of children with and without otitis media with effusion The relationship between acute otitis media and otitis media with effusion (OME) is uncertain and the aetiology of OME is multifactorial. Otitis media with effusion may be an inflammatory condition; both bacteria and viral infections could play a part in this inflammation. The four bacteria Streptococcus pneumoniae, Haemophilus influenza, Staphylococcus aureus and Branhamella catarrhalis cause 60% of the infections whereas S. pneumoniae accounts for up to 35%. IgA provides the dominant surface response to polysaccharide and lipopolysaccharide antigens, of which IgA₂ is the main subclass. Once the mucosa has been breached, most protection is provided by IgG. IgG₂ acts mainly against bacterial capsular antigens. This study looked at two groups of 50 children with and without OME who were aged between 3 and 10 years. The aims were to determine if, firstly, the levels of the serum immunoglobulins were different in the two groups, secondly whether these children made the appropriate antibody response to the capsular antigen to S. pneumoniae (PCP), and finally if there was a delay in the maturity of the IgA response. The total IgG, IgA and all subclass levels were measured using radial immunodiffusion. Levels of functional IgA and IgG were measured using ELISAs (25 patients in each group). The results were analysed with non‐parametric tests. The immunoglobulin levels were within the normal levels for both groups. There were very good correlations between the IgG total anti‐PCP and the IgG₂ anti‐PCP (R > 0.9, p = 0.001). There was a good correlation between the levels of both IgG total and IgG₂ anti‐PCP against IgA total anti‐PCP in both groups (R > 0.85, p > 0.01). This confirms a normal antibody response between both groups of patients. The ages of the controls and patients (50 samples) were correlated with increasing titres of circulating functional antibodies (P = 0.001). This is highly suggestive of a normal age‐related response. In conclusion, the findings were contradictory to our original hypothesis that there is a subtle difference in surface protection between children with and without OME. We believe that a previous history of recurrent acute otitis media is unrelated to the development of OME after 3 years of age.