Subtalar arthrodesis for late sequelae of calcaneal fractures: fusion in situ versus fusion with sliding corrective osteotomy

Primary subtalar arthritis is not common. In most cases, it is the late sequela of intra-articular calcaneal fracture. Subtalar arthrodesis is mostly used for the treatment of traumatic subtalar arthritis in our clinics. We have compared our early cases of in-situ subtalar fusion with our recent cases of fusion with sliding corrective osteotomy in this clinical report. From 1989 to 1992, 15 feet of 13 patients were treated with subtalar arthrodeses for subtalar arthritis caused by malunion of calcaneal fractures. Fusion in situ was done by Ollier's approach, and resection of bony protrusion was done if there was lateral entrapment syndrome. From 1992 to 1995, 13 feet of 12 patients also received subtalar arthrodeses to salvage their calcaneal fractures, but the subtalar fusion was done by wide lateral approach, calcaneal sliding corrective osteotomy, and sometimes (11 of 13 feet) with Achilles tendon lengthening to restore the calcaneal height and width. Patients of both groups experienced obvious clinical improvement in subtalar pain relief, but there was no difference with walking distance, running, or jumping. The group undergoing fusion with sliding corrective osteotomy was more satisfied with regard to cosmetic results and shoe wear. The overall satisfactory rate in the group who underwent fusion with sliding corrective osteotomy (92%) was superior to the group who underwent fusion in situ (77%). Though our method of sliding corrective osteotomy does not provide much improvement to the talus declination angle, it is suitable for those patients with a "banana"-shaped calcaneus malunion. If the patient has prominent anterior ankle pain caused by tibiotalar impingement, we believe that a distraction subtalar arthrodesis would be more appropriate.     

Nidovirus infections: experimental model systems of human neurologic diseases

The presence of terminally differentiated slow- and non-dividing cells in the central nervous system (CNS) provides a safe harbor for viral persistence and latency and constitutes a unique immunologic environment for viral infections. Studies of experimental model systems of viral infections of the CNS provide insight into mechanisms of viral persistence and immune-mediated pathology. Nidoviruses are comprised of 2 families of viruses, coronaviruses and arteriviruses, and are common pathogens of humans and a variety of animal species. Both families of viruses contain neurotropic strains that produce experimental neurologic diseases in rodents. These include acute meningitis and encephalitis; acute poliomyelitis; and chronic inflammatory, immune-mediated, demyelination. Coronavirus-induced demyelinating disease mimics many of the pathologic features of Multiple Sclerosis (MS).     

Laboratory monitoring of pentasaccharide in a dog model of hemodialysis

Varying dosages of pentasaccharide (400-800 nmol/kg) were compared to a 250-U/kg single bolus dosage of unfractionated heparin (UFH) in a dog model of hemodialysis. Several laboratory assays were used to monitor the effects of pentasaccharide and UFH. The pentasaccharide did not produce any anticoagulant effects as measured by the activated partial thromboplastin time. However, in the anti-Xa chromogenic assay and the Heptest assays, there was a dose-dependent prolongation after pentasaccharide administration. In the group of dogs administered 800 nmol/kg of pentasaccharide, there was a 50% decrease in the thrombin antithrombin (TAT) complex level after 60 minutes on dialysis. In the UFH-treated dogs, wide variations in assays were observed. There was a marked elevation in the activated partial thromboplastin time and Heptest assays up to 6 hours after UFH administration. Both anti-Xa and anti-IIa activity was measured up to 4 hours. In the TAT assay, UFH was found to have a stronger effect in suppressing the formation of TAT in comparison to the pentasaccharide. These results suggest that pentasaccharide can be used as a replacement for UFH in a dog model of hemodialysis to keep the dialysis circuit patent. In addition, the anti-Xa-based assays such as the Heptest and the chromogenic anti-Xa assays can be used to monitor the effects of pentasaccharide in this model.     

Simple, Rapid Enzyme-Linked Immunosorbent Assay (ELISA) for the Determination of Rat Osteocalcin

Determination of the concentration of osteocalcin in rat serum is frequently performed using a commercially available radioimmunoassay (RIA). However, this assay takes 3 days to complete, uses radioactive material, and has a narrow linear range. The limited range of the RIA makes it necessary to test multiple dilutions of the sample which frequently results in values that differ, depending on the dilution. In order to overcome these limitations, we have developed an ELISA that utilizes the same standards and anti-rat osteocalcin antiserum, as is used in the RIA. The principle of the ELISA is that the osteocalcin in the sample competes with osteocalcin previously immobilized on a microtiter plate to bind to the available anti-rat osteocalcin antibodies. The amount of antibody bound to the immobilized osteocalcin is determined colorimetrically using a secondary antibody coupled to alkaline phosphatase. This ELISA has a three-log linear response with a sensitivity of 0.1–0.15 ng/ml and intra- and interassay coefficient of variance (CV) values of less than 10%. Most importantly, the assay is rapid and only requires a 2-hour incubation of the sample with the antiserum. The incubation time is important since we and others have observed a significant decrease in the osteocalcin level from serum samples incubated for long periods of time with the antiserum, presumably due to degradation of the osteocalcin. In general, the commercially available RIA gives osteocalcin values that are one-half to one-fourth that of the ELISA because the RIA requires a 48-hour incubation time. Received: 14 November 1997 / Accepted: 9 July 1998     

5-氟尿嘧啶在胰十二指肠切除术患者血液和胰液中的动态分布

探讨５－氟尿嘧啶能否通过胰十二指肠切除术后的残留胰腺组织进入胰液中,并达有效的治疗浓度,为胰腺为临床合理化疗提供理论依据。方法通过观察胰十二指肠切除术患者胰快速推注５－氟尿嘧啶后血液和胰液中药物动态分布及相关性,术后静脉一次性快速推注５－氟尿嘧啶１．０ｇ／ｍ＾２,在给药前后按设计时间点分别采集静脉血和胰液,采用高效液相色谱法测定血浆和胰液５－氟尿嘧啶药物浓度,应用ＰＣＮＯＮＬＩＮ程序程序计算共动态     

Paget病19例

目的 提高对Ｐａｇｅｔ病的诊治水平。方法 回顾性分析１９８７年至１９９７年收治的１９例Ｐａｇｅｔ病的临床表现及诊治方法。结果 本组乳腺Ｐａｇｅｔ病６例,乳腺外１３例,其中阴茎,阴囊１１例,腹股沟处１例,肛周肛管１例。随访时间０．５－１１年,平均５年４个月,随访中３例复发者,其截端切片病理检查均可见病变组织,另１例死于其他疾病。     

Structure-based design of selective inhibitors of dihydrofolate reductase: synthesis and antiparasitic activity of 2, 4-diaminopteridine analogues with a bridged diarylamine side chain

As part of a larger search for potent as well as selective inhibitors of dihydrofolate reductase (DHFR) enzymes from opportunistic pathogens found in patients with AIDS and other immune disorders, N-[(2,4-diaminopteridin-6-yl)methyl]dibenz[b,f]azepine (4a) and the corresponding dihydrodibenz[b,f]azepine, dihydroacridine, phenoxazine, phenothiazine, carbazole, and diphenylamine analogues were synthesized from 2, 4-diamino-6-(bromomethyl)pteridine in 50-75% yield by reaction with the sodium salts of the amines in dry tetrahydrofuran at room temperature. The products were tested for the ability to inhibit DHFR from Pneumocystis carinii (pcDHFR), Toxoplasma gondii (tgDHFR), Mycobacterium avium (maDHFR), and rat liver (rlDHFR). The member of the series with the best combination of potency and species selectivity was 4a, with IC(50) values against the four enzymes of 0. 21, 0.043, 0.012, and 4.4 microM, respectively. The dihydroacridine, phenothiazine, and carbazole analogues were also potent, but nonselective. Of the compounds tested, 4a was the only one to successfully combine the potency of trimetrexate with the selectivity of trimethoprim. Molecular docking simulations using published 3D structural coordinates for the crystalline ternary complexes of pcDHFR and hDHFR suggested a possible structural interpretation for the binding selectivity of 4a and the lack of selectivity of the other compounds. According to this model, 4a is selective because of a unique propensity of the seven-membered ring in the dibenz[b,f]azepine moiety to adopt a puckered orientation that allows it to fit more comfortably into the active site of the P. carinii enzyme than into the active site of the human enzyme. Compound 4a was also evaluated for the ability to be taken up into, and retard the growth of, P. carinii and T. gondii in culture. The IC(50) of 4a against P. carinii trophozoites after 7 days of continuous drug treatment was 1.9 microM as compared with previously observed IC(50) values of >340 microM for trimethoprim and 0.27 microM for trimetrexate. In an assay involving [(3)H]uracil incorporation into the nuclear DNA of T. gondii tachyzoites as the surrogate endpoint for growth, the IC(50) of 4a after 5 h of drug exposure was 0.077 microM. The favorable combination of potency and enzyme selectivity shown by 4a suggests that this novel structure may be an interesting lead for structure-activity optimization.     

THE CHARACTERISTICS OF OVARIAN SEROUS TUMORS OF BORDERLINE MALIGNANCY

During 1948-1976, 363 cases of ovarian serous tumor were encountered in the hospital. Among them, 58 cases were pathologically compatible with the criteria of this tumor of borderline ma- lignancy proposed by the WHO classification. The purp8se of this paper is threefold: 1. To study the c!inical behavior and mode of de- velopment of pathologically documented bordcr- line malignant serous ovarian tumors. 2. To compare the difference between benign, border- line malignant and malignant serous tumors. 3. To assess the value of making such a "borderline malignant" subgroup.     

Cyclopenta-polycyclic aromatic hydrocarbons: potential carcinogens and mutagens

Cyclopenta-polycyclic aromatic hydrocarbons (cyclopenta-PAHs) are a group of compounds that have been detected as environmental pollutants. Perturbation molecular orbital (PMO) calculations on their presumed ultimate carcinogenic metabolites, the cyclopenta-PAH expoxides, predict that they may have a greater biological hazard than the classic PAHs.