Effects of enalapril or nifedipine on muscle strength or functional capacity in elderly subjects. A double blind trial.

INTRODUCTION: The inhibition of angiotensin-converting enzyme could be useful to avoid sarcopenia in the elderly. MATERIALS AND METHODS: We compared in a prospective double blind trial, the effects of treatment with enalapril or nifedipine on muscle performance in hypertensive elderly subjects. Patients were followed for nine months, and at baseline, 4.5 months and the end of follow-up, quadriceps and hand grip muscle strength, walking capacity, timed up and go and the short physical performance test were measured. RESULTS: During follow-up, more subjects on nifedipine than on enalapril discontinued the medication due to side-effects. No differences in the evolution of muscle strength, walking capacity or functional measures were observed. At nine months, plasma angiotensin-converting enzyme activity decreased by 6.0+/-2.5 U/L among patients on enalapril and increased by 8.5+/-4.2 U/L (p<0.001) among patients on nifedipine. CONCLUSION: In this group of elderly subjects, enalapril was not superior to nifedipine with regard to the age-related decline of muscle performance.

Relationship between protein and mitochondrial DNA oxidative injury and telomere length and muscle loss in healthy elderly subjects.

A blood sample and muscle biopsies were obtained from 54 elderly subjects. Twenty-seven subjects aged 77+/-3 years, had experienced a change in fat free mass (FFM) of +194+/-282g/year (lean body mass maintainers) and 27 subjects aged 78+/-3 years, had a change in FFM of -487+/-209g/year (lean body mass losers). Muscle biopsies were also obtained from 10 healthy subjects aged 34+/-4 years. In muscle, the ratio of mitochondrial DNA (mtDNA) to nuclear DNA (nDNA) and telomere length were assessed and deposition of 4-hydroxy-2-nonenal adducts (4HNE) was visualized by electron microscopy. In FFM maintainers, losers and young controls, the ratio of mtDNA to nDNA was 2.1 (95% confidence intervals (CI), 0.1-31.7), 1.5 (95% CI, 0.2-15.7) and 18.6 (95% CI, 2.8-46.2), respectively. 4HNE deposition was 5.9 (95% CI, 1.5-28), 4.9 (95% CI, 0.9-13) and 3.4 (95% CI, 1.1-4.6) gold particles/microm(2), respectively. Telomere length, expressed as T/S ratio, was 0.06 (95% CI, 0.01-0.16), 0.06 (95% CI, 0.03-0.27) and 0.34 (95% CI, 0.1-1.34), respectively (p<0.02 or less for all comparisons between elderly and young subjects).

DNA methylation profile in diffuse type gastric cancer: evidence for hypermethylation of the BRCA1 promoter region in early-onset gastric carcinogenesis.

Diffuse type gastric carcinoma is the most aggressive type of gastric cancer. This type of tumor is not preceded by precancerous changes and is associated with early-onset and hereditary syndromes. To test the hypothesis that DNA methylation profile would be useful for molecular classification of the diffuse type gastric carcinoma, DNA methylation patterns of the CpG Island of 17 genes were studied in 104 cases and 47 normal adjacent gastric mucosa by Methylation-specific PCR, Immunohistochemistry and Hierarchical clustering analysis. The most frequent methylated genes were FHIT, E-cadherin, BRCA1 and APC (>50%), followed by p14, p16, p15, p73, MGMT and SEMA3B (20-49%). Hierarchical clustering analysis reveals four groups with different clinical features. The first was characterized by hypermethylation of BRCA1 and younger age (<45 years old), and the second by hypermethylation of p14 and p16 genes, male predominance and Epstein-Barr virus infection. The third group was characterized by hypermethylation of FHIT and antrum located tumors and the fourth was not associated with any clinical variables. In normal adjacent mucosa only the p73 gene was significantly less methylated in comparison to tumor mucosa. DNA methylation identified subgroups of diffuse type gastric cancer. Hypermethylation of BRCA1 associated with young age suggests a role in early-onset gastric carcinoma.

DNA methylation profile in diffuse type gastric cancer: evidence for hypermethylation of the BRCA1 promoter region in early-onset gastric carcinogenesis

Diffuse type gastric carcinoma is the most aggressive type of gastric cancer. This type of tumor is not preceded by precancerous changes and is associated with early-onset and hereditary syndromes. To test the hypothesis that DNA methylation profile would be useful for molecular classification of the diffuse type gastric carcinoma, DNA methylation patterns of the CpG Island of 17 genes were studied in 104 cases and 47 normal adjacent gastric mucosa by Methylation-specific PCR, Immunohistochemistry and Hierarchicalclustering analysis. The most frequent methylated genes were FHIT, E-cadherin, BRCA1 and APC (>50%),followed by p14, p16, p15, p73, MGMT and SEMA3B (20-49%). Hierarchical clustering analysis reveals four groups with different clinical features. The first was characterized by hypermethylation of BRCA1 and younger age (<45 years old), and the second by hypermethylation of p14 and p16 genes, male predominance and Epstein-Barr virus infection. The third group was characterized by hypermethylation of FHIT and antrum located tumors and the fourth was not associated with any clinical variables. In normal adjacent mucosa only the p73 gene was significantly less methylated in comparison to tumor mucosa. DNA methylation identified subgroups of diffuse type gastric cancer. Hypermethylation of BRCA1 associated with young age suggests a role in early-onset gastric carcinoma.

Analytical detection of immunoglobulin heavy chain gene rearrangements in gastric lymphoid infiltrates by peak area analysis of the melting curve in the LightCycler System.

Because it is difficult to differentiate gastric mucosa-associated lymphoid tissue (MALT) lymphoma from chronic gastritis in gastric lymphoid infiltrates, molecular detection of monoclonality through immunoglobulin heavy chain (IgH) gene rearrangements is commonly performed. However, heterogeneity in the performance and results obtained from IgH gene rearrangements has been reported. To improve the accuracy in the diagnosis of gastric lymphoid infiltrates, we developed an analytical approach based on one-peak area analysis of the melting curve in the LightCycler System. Using a training-testing approach, the likelihood ratio method was selected to find a discriminative function of 4.64 in the training set (10 gastric MALT lymphomas and 10 chronic gastritis cases). This discriminative function was validated in the testing set (five gastric MALT lymphomas, six abnormal lymphocytic infiltrates with subsequently demonstrated gastric MALT lymphomas, and six cases of chronic gastritis). All but one case of gastric MALT lymphoma, as well as abnormal lymphocytic infiltrates, clustered under 4.64, and all chronic gastritis cases clustered above 4.64. These results were validated by conventional electrophoreses confirming one or two sharp bands in cases of gastric MALT lymphomas and a smear of multiple bands in cases of chronic gastritis. Analytical detection of IgH gene rearrangement in gastric lymphoid infiltrates by one-peak area analysis correctly distinguishes gastric MALT lymphomas from chronic gastritis, even in cases with diagnosis of abnormal lymphocytic infiltrates.

Human papillomavirus in esophageal squamous cell carcinoma in Colombia and Chile.

AIM: To examine the presence of human papillomavirus (HPV) in esophageal squamous cell carcinoma (ESCC) specimens collected from Colombia and Chile located in the northern and southern ends of the continent, respectively. METHODS: We examined 47 and 26 formalin-fixed and paraffin-embedded ESCC specimens from Colombia and Chile, respectively. HPV was detected using GP5+/GP6+ primer pair for PCR, and confirmed by Southern blot analysis. Sequencing analysis of L1 region fragment was used to identify HPV genotype. In addition, P16(INK4A) protein immunostaining of all the specimens was conducted. RESULTS: HPV was detected in 21 ESCC specimens (29%). Sequencing analysis of L1 region fragment identified HPV-16 genome in 6 Colombian cases (13%) and in 5 Chilean cases (19%). HPV-18 was detected in 10 cases (21%) in Colombia but not in any Chilean case. Since Chilean ESCC cases had a higher prevalence of HPV-16 (without statistical significance), but a significantly lower prevalence of HPV-18 than in Colombian cases (P = 0.011) even though the two countries have similar ESCC incidence rates, the frequency of HPV-related ESCC may not be strongly affected by risk factors affecting the incidence of ESCC. HPV-16 genome was more frequently detected in p16 positive carcinomas, although the difference was not statistically significant. HPV-18 detection rate did not show any association with p16 expression. Well-differentiated tumors tended to have either HPV-16 or HPV-18 but the association was not statistically significant. HPV genotypes other than HPV-16 or 18 were not detected in either country. CONCLUSION: HPV-16 and HPV-18 genotypes can be found in ESCC specimens collected from two South American countries. Further studies on the relationship between HPV-16 presence and p16 expression in ESCC would aid understanding of the mechanism underlying the presence of HPV in ESCC.

Association of a distinctive strain of Epstein-Barr virus with gastric cancer.

Epstein-Barr virus (EBV) has been linked to gastric carcinoma (GC) with worldwide geographical variations attributable to types and variants of EBV. Here, we compare EBV strains between EBVaGC and healthy donors in Latin America, a high frequency area for EBVaGC. Tumor samples from 73 EBVaGC cases and throat washings from 329 healthy adults were examined for types 1 and 2 EBV and polymorphism at BamHI-F and BamHI-W1/I1 boundary regions and XhoI restriction site in LMP1 gene. Type 1 and prototype F of BamHI- F polymorphism accounted 59 (81%) and 69 (95%) of EBVaGC cases and 257 (78%) and 267 (81%) of healthy donors, respectively. Types I and "i" of BamHI W1/I1 polymorphism accounted 2 (3%) and 62 (85%) of EBVaGC and 85 (26%) and 170 (52%) of healthy donors, respectively (p<0.001). XhoI+ and - polymorphism accounted 60 (82%) and 4 (5%) of EBVaGC and 142 (43%) and 92 (28%) of healthy donors, respectively (p<0.001). Cosegregation analysis demonstrated that most of the 62 type "i" EBVaGC cases harbor XhoI+ strain (81%). However, among 143 type "i" healthy adults, both XhoI polymorphism were present in relatively similar frequencies (XhoI+ 58% and XhoI- 42%) (OR 9.0; 95% CI 1.2-69). Our findings are against to the proposed hypothesis that EBV strains are geographically but not disease-restricted. We conclude that most of the EBVaGC cases harbor a distinctive EBV strain (type "i"/XhoI +), but in healthy donors, this strain was as common as other strains. This finding is contrary to the proposed hypothesis that EBV strains are geographically but not disease-restricted and identified a healthy population group that share the same strain that predominate in EBVaGC cases.

[Clinical and molecular features of cardial gastric cancer associated to Epstein Barr virus]. / Características clínico-moleculares del cáncer gástrico cardial asociado al virus Epstein Barr.

BACKGROUND: Mortality caused by cardial gastric cancer in Chile, is increasing. Previously we demonstrated an association between Epstein Barr virus and this specific location of gastric cancer. AIM: To perform a clinical and molecular characterization of cardial gastric cancer associated to Epstein Barr virus. MATERIAL AND METHODS: Epstein Barr virus was identified in 93 cardial gastric tumors, by in situ hybridization. Clinical and pathological features, survival and expression of p53 and c-erbB2 were compared between tumors with or without the presence of the virus. RESULTS: Twenty two (23.6%) tumors expressed Epstein Barr virus. No difference in sex or age of patients with tumors positive or negative for the virus was observed. Epstein Barr positive tumors had a tendency to have a higher frequency of Bormann III endoscopic appearance and a lower frequency of p53 accumulation (p=0.06). Five years survival was 67% and 42% of tumors positive and negative for the presence of the virus, respectively (p=0.57). CONCLUSIONS: Our results, although not significant, show a tendency towards unique characteristics of cardial gastric tumors associated to Epstein Barr.

[Effects of acute octreotide infusion on renal function in patients with cirrhosis and portal hypertension]. / Efectos de la infusión aguda de octreotido sobre la función renal en pacientes con cirrosis hepática e hipertensión portal.

BACKGROUND: Octreotide is used in the treatment of acute variceal bleeding, based on its inhibitory effects of post-prandial splanchnic hyperemia and splanchnic venoconstriction. The consequences of these haemodynamic changes on renal circulation are not well known in cirrhotic patients. AIM: To evaluate the effects of acute octreotide administration on several parameters of renal function, including free water clearance, in patients with cirrhosis with or without ascites. PATIENTS AND METHODS: Twenty cirrhotic patients, Child-Pugh A orB, with or without ascites, with esophageal varices, normal renal function and free of medications (vasoactive drugs or diuretics) were assigned to 2 different protocols. Protocol 1: 10 patients were randomized to receive octreotide or placebo, as a bolus followed by a continuous infusion. Glomerular filtration rate (GFR) and renal plasma flow (PRF) were measured, in basal conditions and during the drug or placebo administration. Protocol 2: 10 additional patients were randomized in the same way and free water clearance and urinary sodium excretion were again measured in the basal period and during the drug or placebo infusion. RESULTS: After octreotide or placebo administration no significant changes were observed neither in GFR nor in PRF. The free water clearance decreased significantly during octreotide administration (3.12 ml/min+/-1.04 SE vs 0.88+/-0.39, p<.03). In both protocols no changes in mean arterial pressure were observed. CONCLUSIONS: Acute administration of octreotide to cirrhotic patients with portal hypertension, with or without ascites, did not produce any change in glomerular filtration rate or in estimated renal plasm blood flow. However the free water clearance decreased significantly. This effect, under chronic administration, could be clinically important and deserves further studies.

Effects of 5-isosorbide mononitrate and propranolol on subclinical hepatic encephalopathy and renal function in patients with liver cirrhosis.

BACKGROUND/AIMS: In patients with cirrhosis pharmacological treatment of portal hypertension using beta-blockers and vasodilators has raised concerns for its potential deleterious effects on renal function and encephalopathy. To clarify this issue we evaluated the effects of propranolol and 5-isosorbide mononitrate or both on subclinical hepatic encephalopathy and renal function in a prospective randomized double-blinded study. METHODOLOGY: Thirty patients Child-Pugh A or B, with esophageal varices, normal renal function and non-previous pharmacological treatment were studied. After a basal period, patients received during 4 weeks 5-isosorbide mononitrate (80 mg/day) or placebo. In the next 4 weeks, propranolol was added to both groups. At baseline and at the end of each study period we assessed: renal function tests; plasma renin activity and aldosterone; subclinical hepatic encephalopathy (electroencephalograms, visual evoked potentials and psychometric studies). Mean arterial pressure, cardiac output (echo-Doppler) and indocyanine green retention were also measured. RESULTS: The most common alterations at baseline were increased arterial ammonia levels (85%), abnormal indocyanine green retention (75%), abnormal trail making B (44%), decreased inulin clearance (30%) and high plasma renin activity (27%). After 4 weeks of 5-isosorbide mononitrate or placebo no significant changes were observed in any variable. Five out of 14 patients receiving 5-isosorbide mononitrate were withdrawn due to side effects. The addition of propranolol decreased significantly plasma renin activity in both groups and cardiac output in those receiving 5-isosorbide mononitrate but did not change other variables. CONCLUSIONS: In patients with compensated or slightly decompensated liver cirrhosis 5-isosorbide mononitrate, propranolol or the association of both did not produce detectable worsening of subclinical hepatic encephalopathy or renal function.