17O, 14N and 15N n.m.r. studies of the CO2+ complexes of cyclo(Pro17O-Gly15N) and cyclo(Gly17O-Pro) in aqueous solution

The complexation of cyclo(Pro¹⁷O-Gly¹⁵N) and cyclo(Gly¹⁷O-Pro) with CO²⁺ ions has been studied by ¹⁷O, ¹⁴N and ¹⁵N n.m.r. spectroscopy in aqueous solution. ¹⁷O, ¹⁴ N and ¹⁵N transverse relaxation times and chemical shifts were measured as a function of temperature. The ¹⁷O n.m.r. studies unequivocally demonstrate that the cobaltous ion binds to the peptide oxygen of both compounds. The hyperfine coupling constant and the peptide residence times were found to be A =–0.165 MHz and – 0.145 MHz, μ= 16, and 92μsec for cyclo(Pro¹⁷O-Gly¹⁵N) and cyclo(Gly¹⁷O-Pro), respectively. The ¹⁴N and ¹⁵N studies of labeled cyclo(Pro¹⁷O-Gly¹⁵N) do not indicate binding at either the Gly¹⁵N or the Pro¹⁴N site.     

Atrial Natriuretic Peptide during Exercise in Patients with Coronary Heart Disease before and after Single Dose Atenolol and Acebutolol

Plasma atrial natriuretic peptide (ANP) was measured during dynamic exercise in 10 patients with coronary heart disease before and after single dose atenolol 50 mg and acebutolol 200 mg, respectively. Systolic blood pressure, heart rate and the rate-pressure product increased during exercise before and after β-blockade, but levels were lower after β-blockade. Plasma ANP levels at rest were unchanged after atenolol, but rose after acebutolol (p<0.01). During exercise plasma ANP increased significantly both before and after β-blockade, but plasma ANP levels were higher after acebutolol at all workloads (p<0.05), whereas plasma ANP levels after atenolol were higher at 125 W exclusively (p<0.05). The augmented ANP levels during exercise after β-blockade probably reflect catecholamine-stimulated ANP release, whereas the elevated plasma ANP levels after acebutolol at rest might be a β-adrenoceptor-mediated ANP release due to the intrinsic sympathomimetic effect of acebutolol.     

Prognostic value of the ankle‐brachial index in elderly patients with a stable chronic cardiovascular event

Summary. Background and Objectives: Patients with polyvascular arterial disease have a greater risk of suffering a new atherothrombotic episode than those with involvement of only one vascular territory. We have studied the predictive prognostic value of the detection of non‐diagnosed peripheral arterial disease, determined by measuring the ankle‐brachial index in a population of elderly patients with stable chronic cardiac or cerebrovascular disease. Methods: This was a multicenter, prospective cohort study with consecutive inclusion of patients between 65 and 85 years of age with a previous atherothrombotic event, but without previously established peripheral arterial disease. Results: A total of 1096 patients were evaluated during 11.7 (± 2.2) months of follow‐up. An ankle‐brachial index of < 0.9 was observed in 29.9% and > 1.4 in 6.9%. The detection of an ankle‐brachial index < 0.9 was clearly associated with the presence of a combined primary event of cardiovascular death and non‐fatal cardiovascular event [HR 1.99 (95% CI, 1.49–2.66; P < 0.001)]. There was also a significant relationship between ankle‐brachial index > 1.4 and total (P = 0.001) or cardiovascular (P = 0.020) deaths. The predictive value of both ranges of the ankle‐brachial index was maintained after adjusting for age, sex, diabetes mellitus, vascular territory, macroalbuminuria or glomerular filtration rate. Conclusions: The detection of non‐diagnosed peripheral arterial disease in patients with stable coronary or cerebrovascular events identifies a very high risk population that might benefit from more intensive treatment.     

A type‐specific study of human papillomavirus prevalence in cervicovaginal samples in three different Spanish regions

Human papillomavirus (HPV) is the most frequent sexually transmitted viral infection. It is necessary to know HPV genotype distribution to identify how many women will be protected by HPV vaccines. During a period of 18 months, we have analyzed 2362 HPV positive reporting data from a secondary demand screening program in three regions in Spain (Cantabria, Leon and Burgos). The study has been conducted using polymerase chain reaction and tube array hybridization covering the 35 HPV genotypes described as affecting anogenital mucosa. There were no significant differences between the three regions according to genotype distribution. The most frequent were HPV16 (19.18%), HPV53 (11.26%) and HPV58 (7.66%). HPV18 was the source of 4.02% of infections. High‐risk HPVs were found in 1863/2362 cases. HPV16 was present in 24.3% of high‐risk infections and HPV18 was found in 5.1%. Uncommon genotypes (<5% of the total prevalence each) were found in 17,9% of the total high‐risk infections (334/1863). Multiple infections were diagnosed in 22% of the cases. The HPV genotype distribution is different from previously published data when multiple types are included in the screening. Both HPV16/18 account for 30% of high‐risk infections in a clinical setting in Spain. The presence of multiple genotypes is very common among the population.     

Sodium Bicarbonate versus Sodium Chloride and Oral N‐Acetylcysteine for the Prevention of Contrast‐Induced Nephropathy in Advanced Chronic Kidney Disease

Introduction: Contrast‐induced acute kidney injury (CI‐AKI) is one of the leading causes of hospital‐acquired acute kidney injury. Multiple clinical studies have proposed several preventive strategies. Aims: To examine the efficacy of sodium bicarbonate compared with sodium chloride and oral N‐acetylcysteine (NAC) for preventive hydration after cardiac catheterization. Methods: We conducted a prospective, single‐center trial. Patients with chronic kidney disease (CKD) stage III–IV undergoing cardiac catheterization were allocated to receive either an infusion of 0.9% sodium chloride and oral NAC or 154 mEq/L sodium bicarbonate. Main: Outcome measure CI‐AKI, defined as an increase of 25% or 0.3 mg/dL or more in plasma creatinine within 2 days of contrast administration. Results: Ninety‐three patients were allocated to one of the two groups: 42 patients in the saline plus NAC group and 51 patients in the bicarbonate group. There were no statistically significant differences between the groups in the most important clinical and procedural characteristics. Baseline plasma creatinine levels, estimated glomerular filtration rate, incidence of diabetes mellitus, hypertension, congestive heart failure, and contrast medium volume were similar. Mean plasma creatinine concentration was 1.76 ± 0.54 mg/dL in the saline and NAC group and 1.9 ± 1 mg/dL in the bicarbonate group (P = 0.23). The rate of CI‐AKI was 9.8% in the bicarbonate group and 8.4% in the saline plus NAC group. No patient required renal replacement therapy. Conclusion: Hydration with sodium bicarbonate is not more effective than hydration with sodium chloride and oral NAC for prophylaxis of CI‐AKI in patients with CKD stage III–IV undergoing cardiac catheterization.     

M. tuberculosis-Complex Specific T-Cell Stimulation and DTH Reactions Induced With a Peptide from the 38-kDa Protein

An immunodominant T-cell-stimulatory epitope located near the carboxy terminus of the 38-kDa antigen from M. tuberculosis (38.G, residues 350-369) was found to be M. tuberculosis-complex specific. This was demonstrated by the presence of proliferative and delayed type hypersensitivity (DTH) responses in mice immunized with Mycobacterium tuberculosis and Mycobacterium bovis BCG, whereas mice immunized with M. avium or other non-tuberculous species of mycobacteria showed no such responses. Peptide 38.G stimulated the proliferation of peripheral blood lymphocytes from healthy purified protein derivative (PPD)-positive individuals but not from PPD-negative individuals. It also elicited DTH responses in M. tuberculosis sensitized mice and in PPD-positive healthy human volunteers. Peptide 38.G could therefore prove to be an important component in any new molecularly defined reagent used in the immunodiagnosis of tuberculous infection.     

Immune response and in vivo production of cytokines in patients with liver hydatidosis

Cytokines play an important role in the human immunological response, but the exact role of cytokines in the human immune response against parasites, especially against Echinococcus granulosus, remains unclear. IL-1, IL-2, IL-4 and tumour necrosis factor (TNF) levels in peripheral blood of 21 patients with liver hydatidosis were evaluated before surgical treatment, and the levels of IgA, IgM, IgG, IgE, specific IgE against E. granulosus, C3, C4 and BF complement fractions and CD20, CD3, CD4, CD8 and CD16 cell percentages were also determined, as was the relationship between these variables and cytokine levels. Data from hydatid patients were compared with data obtained from 21 healthy volunteers. Hydatid patients showed increases of IgG, IgE, IgEs and IL-2 (P< 0.01), and decreases of IL-1 and TNF levels (P< 0.001), but these variables (respectively) increased in patients showing cysts in the central area of the liver or with a wide opening of cysts in the biliary tract. The increase of IL-1, IL-2 and IL-4 showed a close relationship with the number, characteristics and above all the location of cysts within the liver itself. IgG and IL-4 levels and also IgG and IgE levels showed a significant correlation (P< 0.05).