[Cardiovascular diseases and osteoporosis: what is common?].

The review analyzes the possible effect of cardiac drugs on the course of osteoporosis (OP). The fact that atherosclerosis and OP share the mechanisms of development, among which the enhanced activity of the sympathetic part of the autonomic nervous system and endothelial dysfunction are most important, is beyond question now. In this connection, beta-adrenoblockers, nebivolol in particular, attract attention. Nebivolol is known to be a selective beta1-adrenoblocker that has an additional vasodilator property, by stimulating the synthesis of nitric oxide. This may serve to increase bone mineral density and slow down the progression of OP. At the same time, most investigations in this area are retrospective therefore final conclusions call for randomized prospective studies that will be able to evaluate more objectively the effect of cardiac drugs on the prevention of OP or its progression delay.

[The problem of the effectiveness of treatment of arterial hypertension in smokers].

In this review we give short characteristics of investigations devoted to assessment of effectiveness of cardiac drugs in patients who smoke. Basing on results of these investigations point of view is expressed that antihypertensive preparations of various classes differently affect smokers with arterial hypertension (AH). An opinion exists that drugs which improve endothelial function are preferable in smoking patients with AH. However special studies of comparative of efficacy of antihypertensive drugs from different classes in smokers are necessary.

Initial antimicrobial effect of controlled-release doxycycline in subgingival sites.

OBJECTIVES: To determine the ability of a 10% doxycycline hyclate controlled-release polymer (Atridox) to suppress periodontopathic bacteria when placed subgingivally following scaling and root planing (Sc/Rp). METHODS: Eight males and seven females, mean age 48 years, with moderate to advanced periodontitis participated in the study. In each patient, bilateral periodontal pockets probing 6-7 mm were randomly assigned to treatment by Sc/Rp + doxycycline polymer or by Sc/Rp alone. Subgingival placement of doxycycline polymer was carried out according to the manufacturer's instructions. Sc/Rp was performed with hand instruments for at least 10 min in each study tooth. Subgingival samples were collected by paper-points at baseline, at 2 weeks and at 4 weeks post-treatment. Culture methodology was used to isolate and identify putative periodontal pathogens, including Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Dialister pneumosintes, Tannerella forsythia, Prevotella intermedia/Prevotella nigrescens, Campylobacter species, Eubacterium species, Fusobacterium species, Peptostreptococcus micros, Eikenella corrodens, Staphylococcus species, enteric gram-negative rods, beta-hemolytic streptococci and yeasts. The microbiologic examination was carried out blindly. Microbiological data were analyzed using a General Linear Model Analysis of Variance for within and between group effects. RESULTS: Sites receiving Sc/Rp + doxycycline polymer and sites receiving Sc/Rp alone exhibited similar levels of periodontal pathogens at baseline and did not differ significantly in total viable counts and proportional recovery of periodontopathic bacteria post-treatment. CONCLUSIONS: Controlled-release doxycycline placed in moderate to deep periodontal pockets caused no significant additional reduction in the subgingival pathogenic microbiota compared to thorough Sc/Rp alone. Since controlled-release doxycycline may not significantly suppress several subgingival pathogenic microorganisms and seems to possess no distinct advantage over broad-spectra, safe and inexpensive antiseptics, the rationale for its employment in periodontal therapy remains unclear.

Human cytomegalovirus-associated periodontitis in renal transplant patients.

BACKGROUND: Human cytomegalovirus (HCMV) infection is associated with renal transplant failure. Periodontal pockets may be reservoirs for HCMV replication. OBJECTIVES: This study was done to determine active HCMV replication in saliva and gingival crevicular fluid of renal transplant patients affected by periodontitis. METHODS: HCMV pp67-mRNA amplification was analyzed in oral fluids of 38 transplant recipients at 6 months' posttransplantation. Patients received antiviral therapy until 3 months' posttransplantation. The HCMV-positive cell line VR-977 was the positive control, and oral fluids from healthy volunteers served as the negative control. Periodontitis was diagnosed by clinical examination. Serum HCMV IgG and IgM were analyzed to differentiate recent and latent infection. RESULTS: Prevalence of gingival overgrowth was 68.4%. HCMV gene transcripts were detected in the saliva of 21% and the gingival crevicular fluid of 18% of patients. All patients (100%) with HCMV pp67-mRNA detected in saliva demonstrated clinical manifestations of viral infection, as did 86% of patients with HCMV pp67-mRNA detected in the gingival crevicular fluid. Serum IgM was positive in 7.9% of patients and IgG in 65.8%; however, associations with active mRNA replication were not statistically significant. CONCLUSIONS: Renal transplant patients affected by periodontitis are at risk of viral replication within the periodontal tissues despite antiviral therapy. This study suggests that use of HCMV pp67-mRNA detection in saliva and gingival crevicular fluid provides markers of active viral infection, and evidence for a link between HCMV-associated periodontitis and renal transplant complications.

Prevalence of activating ras mutations in morphologically characterized thyroid nodules.

Ras proteins are signal-transducing proteins that share common properties with membrane-anchored G proteins. Mutations at codon 12/13 or codon 61 alter GTP-binding or GTPase activity, respectively. Such activating mutations are present in nearly 30-50% of various malignancies including colon, breast, and lung carcinomas. There are conflicting data regarding the prevalence of ras mutations in the thyroid and their possible pathogenetic role in the different tumor types. To address this question, we examined 45 morphologically characterized thyroid carcinomas, adenomas, and hyperplastic nodules using a highly sensitive single-stranded conformation polymorphism (SSCP) approach combined with DNA-sequencing. DNA from cell lines with known mutations served as controls. A G to A H13 codon substitution replacing an Asp for a Gly residue was detected in 1 papillary carcinoma. Although no H12 or H61 codon substitutions were identified, 2 discrete alterations were identified in codons H17 and 22. No N12/13 codon substitutions were identified. N61 codon substitutions of A to G resulting in a Gly to Arg substitution were detected in 2 papillary carcinomas; the same mutation was also found in one follicular adenoma. Interestingly, K12/13 and K61 ras mutations were not present in any of the tumors examined. These data establish a low prevalence of mutations in all ras gene family members in human thyroid neoplasms. This difference from neoplasms of other organs may explain the relatively indolent biologic behavior of many thyroid tumors and supports an alternate early genetic mutation that is more characteristic of these neoplasms.

Altered hemodynamic response to isosorbide dinitrate in essential hypertension.

Relaxation produced by nitrates on venous, arteriolar, and large arterial vessels is well known but has never been studied in human hypertensive aortas studied in vivo. In this investigation, the effects of acute oral administration of 20 mg of isosorbide dinitrate were evaluated in 12 patients with sustained essential hypertension and nine normotensives of the same age. Noninvasive measurements of systolic, diastolic, and mean arterial pressure, carotid-femoral pulse wave velocity and aortic-arch diastolic diameter using suprasternal echocardiography were determined before and 3 hours after drug administration. In normal subjects, isosorbid dinitrate significantly decreased systolic blood pressure and pulse pressure but did not affect diastolic and mean arterial pressure. In contrast, in hypertensives, the same dosage of isosorbid dinitrate decreased together systolic, diastolic mean, and pulse pressure. In both populations, pulse wave velocity decreased significantly whereas aortic arch diastolic diameter increased markedly. The increase was observed mainly in normal subjects. The study provided evidence that (1) both in normal subjects and hypertensives, isosorbide dinitrate caused an increase in aortic diameter together with an increase in arterial distensibility; and (2) the changes in mean arterial pressure were significant only in hypertensives, indicating that the altered vasodilator response in essential hypertension is not endothelium-mediated.