NITRIC OXIDE-DEPENDENT ENDOTHELIAL FUNCTION IS UNAFFECTED BY ALLOPURINOL IN HYPERCHOLESTEROLAEMIC SUBJECTS

1. Hypercholesterolaemia is associated with abnormal endothelium-related vasodilator function, possibly due to increased destruction .NO by superoxide anions (.O2-). Oxypurinol, a xanthine oxidase (XO) inhibitor with anti-oxidant properties and the active metabolite of the commonly used drug allopurinol, reduces .NO quenching in vitro and has been reported to acutely improve endothelial function in hypercholesterolaemic subjects. 2. The purpose of the present study was to determine whether oral allopurinol improves .NO dilator function in hypercholesterolaemic subjects. 3. A randomized double-blind, placebo-controlled cross-over design evaluated the effect of allopurinol (300 mg daily for 4 weeks) on forearm blood flow (FBF) responses to intrabrachial infusion of acetylcholine (ACh), sodium nitroprusside (SNP) and NG-monomethyl-L-arginine (L-NMMA) in nine hypercholesterolaemic subjects. 4. Endothelium-dependent vascular responses to ACh and L-NMMA were not significantly altered by allopurinol. The endothelium-independent vasodilator response to SNP was similarly unchanged. 5. These results indicate that allopurinol does not influence basal or stimulated activity of the .NO dilator system in hypercholesterolaemic subjects. If intracellular .O2- inactivation .NO is responsible for endothelial dysfunction in hypercholesterolaemia, the source may be other than XO dependent. However, generation of .O2- during the conversion of allopurinol to oxypurinol could offer an alternative, and probably more likely, explanation for the ineffectiveness of allopurinol in vivo.     

牡丹根药理作用的研究

目的：通过对牡丹根药效学和毒性的研究,为牡丹根的综合利用提供药理学依据。方法;采用比浊法,玻片法,观察牡丹根的凝血作用,耳肿法,足跖肿胀法和士的宁惊厥法,分别判断其抗炎及抗惊厥作用;同时对其降压作用和毒性进行测定。结果;大剂量１５ｇ／ｋｇ牡丹根在促进血小板聚集,抗炎,降压及抗惊厥方面均有显著的作用,与丹皮比较,无显著性差异。     

Vergleichende Untersuchung sagittaler und koronaler MRT mit histologischen Diskus- und Kiefergelenkpräparaten zur Prüfung einer Identität von anteriorer Diskusdislokation und anterioren Kapselbindegeweben

Problem. Anterior dislocation of the articular disk of the temporomandibular joint (TMJ) found by MRI tomography often presents a problem. It may persist in MRI despite improvement of articular symptoms and even be found in healthy persons free of any symptoms. Can this be explained by the similarity in structure of the anterior connective tissue of the disk and capsule and their pathological changes? Is a second coronal plane required for MRI investigation? Material and methods. The preauricular regions of 72 patients of the TMJ clinic were examined by oblique-sagittal and oblique-coronal MRI. A Siemens-Vision MRI was used. It was also possible to prepare 10 articular disks of the TMJ with anterior capsular tissue as well as 20 complete TMJs of adults from autopsy material. Sagittal, transversal, and horizontal serial sections were examined histologically. Results. In 49 of the 72 cases examined, an anterior dislocation without reduction found in the sagittal MRI was not confirmed in the oblique-coronal MRI. In the sagittal MRI it was possible to differentiate three, in the coronal MRI six typical forms of magnetic resonance signals, which are represented in figures. They are compared with anatomical and histological connective tissue findings adjacent to the TMJ. The structural similarity of the disk and anterior capsular tissue of the TMJ is demonstrated. The close connection of the disk and connective tissue surrounding the TMJ makes differentiation of MRI findings difficult especially following regressive and adaptive reactions. Conclusions. In MRI, anterior capsular tissue is able to simulate dislocation of the disk. Pathological tissue reactions may alter the MRI signal and lead to the wrong diagnosis of dislocation of the disk. Diagnosis of an anterior disk dislocation cannot be established solely on the basis of oblique-sagittal MRI findings.     

Periodontal health and HIV infection

Despite a large amount of research of periodontal health seen in HIV infection, much remains to be learned. Very few large controlled studies of infected people at settings not self-selected for oral disease have been reported, and few have investigated the necrotising periodontal diseases described in HIV infection. In this paper we present a brief review of three approaches to identify periodontal changes associated with HIV infection and identify possible aetiological factors for them. First, we summarise the methods and findings of a controlled blinded study of the periodontal health of homosexual men attending a genito-urinary medicine clinic. Second, we précis a case-control study of gingival ulceration among patients at a dedicated dental clinic. Finally, we outline how the validity of diagnostic criteria for HIV-associated periodontal changes were tested against the data collected in the controlled study.     

Severe oral ulceration in patients with HIV infection: A case series

OBJECTIVE: Oral ulceration occurs in an estimated 2–4% of patients with HIV infection. This retrospective observational study describes the aetiology and characteristics of 94 HIV-positive patients with either severe and/or recurrent oral ulceration presenting at a dedicated HIV dental unit over a 4-year period. METHODS: Case records were reviewed for diagnosis investigations, CD4 count, CDC stage and treatment modality. RESULTS: Of the 94 patients 50% had an AIDS diagnosis. In patients with asymptomatic HIV disease minor recurrent oral ulceration was the commonest diagnosis whilst large non-specific neutropenic ulcers were more frequently seen in patients with symptomatic disease with low CD4 counts. A variety of treatment modalities were used including thalidomide. An algorithm is presented for the management of patients with severe oral ulceration.     

Design of the Dutch Obesity Intervention in Teenagers (NRG-DOiT): systematic development, implementation and evaluation of a school-based intervention aimed at the prevention of excessive weight gain in adolescents

Background

Immigrants to the U.S. are required to undergo overseas screening for tuberculosis (TB), but the value of evaluation and treatment following entry to the U.S. is not well understood. We determined the cost-effectiveness of domestic follow-up of immigrants identified as tuberculosis suspects through overseas screening.

Methods

Using a stochastic simulation for tuberculosis reactivation, transmission, and follow-up for a hypothetical cohort of 1000 individuals, we calculated the incremental cost-effectiveness of follow-up and evaluation interventions. We utilized published literature, California Reports of Verified Cases of Tuberculosis (RVCTs), demographic estimates from the California Department of Finance, Medicare reimbursement, and Medi-Cal reimbursement rates. Our target population was legal immigrants to the United States, our time horizon is twenty years, and our perspective was that of all domestic health-care payers. We examined the intervention to offer latent tuberculosis therapy to infected individuals, to increase the yield of domestic evaluation, and to increase the starting and completion rates of LTBI therapy with INH (isoniazid). Our outcome measures were the number of cases averted, the number of deaths averted, the incremental dollar cost (year 2004), and the number of quality-adjusted life-years saved.

Results

Domestic follow-up of B-notification patients, including LTBI treatment for latently infected individuals, is highly cost-effective, and at times, cost-saving. B-notification follow-up in California would reduce the number of new tuberculosis cases by about 6–26 per year (out of a total of approximately 3000). Sensitivity analysis revealed that domestic follow-up remains cost-effective when the hepatitis rates due to INH therapy are over fifteen times our best estimates, when at least 0.4 percent of patients have active disease and when hospitalization of cases detected through domestic follow-up is no less likely than hospitalization of passively detected cases.

Conclusion

While the current immigration screening program is unlikely to result in a large change in case rates, domestic follow-up of B-notification patients, including LTBI treatment, is highly cost-effective. If as many as three percent of screened individuals have active TB, and early detection reduces the rate of hospitalization, net savings may be expected.     

Extension of intracranial thrombosis after unilateral dissection of the internal jugular vein

OBJECTIVE: Resection of the internal jugular vein can be necessary in cases of radical neck dissection or even in cases involving benign neoplasms such as glomus tumors. According to the triad described by Virchow (ie, stasis of blood flow, damage to the endothelium, and changes in hemostasis), the development of a thrombosis in the venous vessels superior to the resected internal jugular vein seems to be possible. The aim of this study was to determine the extension of possible intracranial thrombosis after wound healing. DESIGN: A total of 17 patients requiring resection of the internal jugular vein were evaluated prospectively using magnetic resonance imaging and 2-dimensional (time-of-flight) magnetic resonance angiography after the surgical treatment. Preoperative magnetic resonance images were obtained in all 17 patients for staging purposes as well as to exclude preoperative thrombosis of the internal jugular vein. Sixteen patients had malignant tumors, and 1 patient had a glomus tumor. RESULTS: Intracranial thrombosis with thrombosis of the sigmoid sinus was found in 4 patients, and thrombosis of the transverse sinus was found in 3 patients. There were no complications such as intracranial hemorrhage or signs of increased intracranial pressure in any patients. There was no evidence of intracranial thrombosis in 10 cases. In these cases, thrombosis of the venous vessels superior to the resected vein ranged from none to complete thrombosis of the superior bulb of the internal jugular vein. After unilateral resection of the internal jugular vein, the venous blood leaves the brain mainly via the venous network of the contralateral side of the neck. CONCLUSIONS: Although intracranial thrombosis of the sigmoid or transverse sinus seems to occur more frequently than was previously thought, intracranial complications such as venous infarction or increased intracranial pressure appear to be very rare. After unilateral radical neck dissection, the venous blood leaves the brain mainly via the venous system of the other side of the neck and the ipsilateral collateral veins.     

Labyrinthine ossification: etiologies and CT findings

Ossification of the membranous labyrinth (labyrinthitis ossificans) develops as the final result of many inflammatory processes, for example, meningitis, blood-borne septic emboli, middle ear infection, and cholesteatoma. Labyrinthine ossification may also occur as a result of previous labyrinthectomy or secondary to trauma. Seven cases of labyrinthine ossification accompanied by severe vertigo and total hearing loss in the affected ear are discussed. The computed tomographic appearance of varying degrees of ossification, the clinical and surgical circumstances from which this disorder may develop, and the various approaches to labyrinthectomy are described.