Angiotensin II increases parathyroid hormone-related protein (PTHrP) and the type 1 PTH/PTHrP receptor in the kidney

Angiotensin II (AngII) participates in the pathogenesis of kidney damage. Parathyroid hormone (PTH)-related protein (PTHrP), a vasodilator and mitogenic agent, is upregulated during renal injury. The aim of this study was to investigate the potential relation between AngII and PTHrP system in the kidney. Different methods were used to find that both rat mesangial and mouse tubuloepithelial cells express PTHrP and the type 1 PTH/PTHrP receptor (PTH1R). In these cells, AngII increased PTHrP mRNA and protein production. In contrast, PTH1R mRNA was increased in mesangial cells and downregulated in tubular cells, but its protein levels were unmodified in both cells. AT(1) antagonist, but not AT(2), abolished AngII effects on PTHrP/PTH1R. The in vivo effect of AngII was further investigated by systemic infusion (a low dose of 50 ng/kg per min) into normal rats. In controls, PTHrP immunostaining was mainly detected in renal tubules. In AngII-infused rats, PTHrP staining increased in renal tubules and appeared in the glomerulus and the renal vessels. After AngII infusion, PTHR1 staining was markedly increased in all these renal structures at day 3 but remained elevated only in tubules at day 7. The AT(1) antagonist, but not the AT(2), significantly diminished AngII-induced PTHrP and PTHR1 overexpression in the renal tissue, associated with a decrease in tubular damage and fibrosis. The results indicate that AngII regulates renal PTHrP/PTH1R system via AT(1) receptors. These findings demonstrate that PTHrP upregulation occurs in association with the mechanisms of AngII-induced kidney injury.     

Randomized phase III study of 3-weekly versus weekly docetaxel in pretreated advanced non-small-cell lung cancer: a Spanish Lung Cancer Group trial.

BACKGROUND: Docetaxel is a widely accepted second-line treatment in advanced non-small-cell lung cancer (NSCLC) with a risk of myelotoxicity. This study evaluated the efficacy and toxicity profile of two docetaxel regimens in NSCLC patients who had failed first-line non-docetaxel-based chemotherapy. PATIENTS AND METHODS: A total of 259 patients from 33 Spanish centers were randomized to receive either docetaxel 75 mg/m(2) administered every 3 weeks (3W arm) or docetaxel 36 mg/m(2) given weekly (1W arm) for 6 weeks followed by 2 weeks of rest. The primary end point was 1-year survival; secondary end points were median survival, time to progression, response and toxicity. RESULTS: One-year survival was 27% in the 3W and 22% in the 1W arm. Median time to progression was also similar in the two arms. Median survival was 6.6 months in the 3W arm versus 5.4 months in the 1W arm (P = 0.075). Response rates were 9.3% in the 3W arm and 4.8% in the 1W arm. More patients in the 1W arm experienced mucositis [1W, nine patients (7.2%); 3W, two patients (1.6%); P = 0.032], while febrile neutropenia was significantly higher in the 3W arm [3W, 10 patients (7.8%); 1W, one patient (0.8%); P = 0.010]. CONCLUSIONS: Both weekly and 3-weekly docetaxel were effective and well-tolerated, with different toxicity profiles. In general, there was no indication to recommend the weekly schedule. However, the significant lower rate of febrile neutropenia observed in the weekly schedule makes it a good alternative for patients at risk of severe neutropenia.     

Comparison of the free radical-scavenging activity of propolis from several regions of Argentina

Propolis is extensively used in Argentine folk medicine. Alcoholic extracts of propolis from different regions of Argentina were prepared. The extracts were analysed for the determination of total flavonoid content (from 13.3 to 42.6 mg/g of propolis) by using the aluminum nitrate method, UV spectrophotometry and thin layer chromatography. All of them contained high total flavonoid content. It was also observed that all samples of ethanolic extracts of propolis showed free radical-scavenging activity in terms of scavenging of the radical DPPH but the highest activities were found for samples from Tucumán and Santiago del Estero. In all cases with 20 microg/ml of soluble principles, the percentage of DPPH degradation was different (Banda Oeste: 67.5%; Verónica: 45%; Forres: 35%; Saenz Pe?a: 20% and Juan José Castelli: 55%). These results may justify their use as a source of natural antioxidants.     

Evaluation of antimicrobial treatments in children with acute otitis media in Spain: a pharmacokinetic-pharmacodynamic (PK/PD) approach

Pharmacokinetic/pharmacodynamic (PK/PD) principles are priceless tools for evaluating the effectiveness of different antimicrobial treatments for different infections. However, very few studies deal with pediatric dosages and take into account the unbound drug serum levels. Our study is focused on the most frequent antibiotic dosing schedules used in Spain for the treatment of acute otitis media (AOM) in children, where high rates of penicillin and macrolide resistance exist among pneumococcal isolates. Pharmacokinetic parameters of antibiotics in children where obtained from the literature. The minimum inhibitory concentrations (MIC90) of antibiotics for pediatric strains of Streptococcus pneumoniae and Haemophilus influenzae were obtained from the SAUCE 2 project. Only ceftriaxone (50 mg/kg single intramuscular dose) and high doses of co-amoxiclav (27-33 mg/kg q8h) provided adequate efficacy indexes (tss(%)>MIC) for both S. pneumoniae and H. influenzae in AOM in children. These results are consistent with MEF (medium ear fluid) levels obtained from the literature. Our results confirm the utility of serum unbound levels to predict efficacy of antibiotics in children with AOM.     

Influence of renal function on the pharmacokinetics of piperacillin/tazobactam in intensive care unit patients during continuous venovenous hemofiltration

The pharmacokinetics of piperacillin/tazobactam (4 g/0.5 g every 6 or 8 hours, by 20-minute intravenous infusion) were studied in 14 patients with acute renal failure who underwent continuous venovenous hemofiltration with AN69 membranes. Patients were grouped according to severity (CL(CR) < or =10 mL/min, 10 < CL(CR) < or =50 mL/min, and CL(CR) > 50 mL/min). A noncompartmental analysis was performed. The sieving coefficient (0.78 +/- 0.28) was similar to the unbound fraction (0.65 +/- 0.24) for tazobactam, but it was significantly different (0.34 +/- 0.25) from the unbound fraction (0.78 +/- 0.14) for piperacillin. Extracorporeal clearance was 37.0% +/- 28.8%, 12.7% +/- 12.6%, and 2.8% +/- 3.2% for piperacillin in each group and 62.5% +/- 44.9%, 35.4% +/- 17.0%, and 13.1% +/- 8.0% for tazobactam. No patients presented tazobactam accumulation. In patients with CL(CR) < 50 mL/min, t(%)ss >MIC90 values were 100% for a panel of 19 pathogens, but in those with CL(CR) > 50 mL/min, t(%)ss >MIC90 indexes were 55.5% and 16.6% for pathogens with MIC90 values of 32 and 64. The extracorporeal clearance of piperacillin/tazobactam is clinically significant in patients with CL(CR) > 50 mL/min, in which the risk of underdosing and clinical failure is important and extra doses are required.     

Laparoscopic drainage of bilateral tuberculous psoas abscesses

Psoas abscess secondary to Mycobacterium tuberculosis infection is rare in industrialized countries. Standard treatment options for psoas abscess of any etiology include percutaneous drainage under radiographic guidance and surgery, which is reserved for failure of conservative therapy. A case of bilateral tuberculous psoas abscesses is reported and a surgical method of drainage utilizing a totally extraperitoneal laparoscopic approach is described.     

Posterior fontanelle sonography: an acoustic window into the neonatal brain

BACKGROUND AND PURPOSE: Sonographic brain studies are classically performed through the anterior fontanelle, but visualization of posterior supratentorial and infratentorial structures is poor with this approach. Posterior fontanelle sonography is recommended for better assessment of these structures. Our purpose was 1) to determine whether sonography of the brain through the posterior fontanelle (PF) improves visualization of brain lesions when added to the routine anterior fontanelle (AF) approach and 2) to describe standardized PF coronal and sagittal sections. METHODS: In this prospective study (conducted from February 1999 to January 2001), PF sonography was added to AF sonography in 165 consecutive premature neonates with a birth weight of < 2000 g. Sonograms were recorded in digital format for re-evaluation at the end of the study. Lesions were grouped as congenital, infectious, hemorrhagic, or hypoxic-ischemic. The chi2 test for paired data and the kappa coefficient were used to compare diagnoses with AF alone and diagnoses with AF plus PF. RESULTS: PF sonography was performed in 164 of 165 patients. Results were normal in 86 and abnormal in 78. The single posterior fossa malformation detected in this series was best delineated with the PF approach. PF sonography increased the diagnostic rate of grade II hemorrhage by 32%. Cerebellar hemorrhage (two patients) and cerebellar abscesses (one patient) were diagnosed by using the PF approach. PF sonography did not contribute to the diagnosis of periventricular leukomalacia. CONCLUSION: Study of the neonatal brain with the addition of PF sonography afforded greater accuracy in detecting intraventricular hemorrhage compared with AF sonography alone, especially when the ventricle was not dilated. The PF approach better defines posterior fossa malformations.     

Fibrosis in hypertensive heart disease: role of the renin-angiotensin-aldosterone system

Structural homogeneity of cardiac tissue is governed by mechanical and humoral factors that regulate cell growth, apoptosis, phenotype, and extracellular matrix turnover. ANGII has endocrine, autocrine, and paracrine properties that influence the behavior of cardiac cells and matrix by AT1 receptor binding. Various paradigms have been suggested, including ANGII-mediated up-regulation of collagen types I and III formation and deposition in cardiac conditions, such as HHD. A growing body of evidence, however, deals with the potential role of aldosterone, either local or systemic, in inducing cardiac fibrosis. Aldosterone might also mediate the profibrotic actions of ANGII. To reduce the risk of heart failure that accompanies HHD, its adverse structural remodeling (eg, myocardial hypertrophy and fibrosis) must be targeted for pharmacologic intervention. Cardioprotective agents must reverse not only the exaggerated growth of cardiac cells, but also regress existing abnormalities in fibrillar collagen. Available experimental and clinical data suggest that agents interfering with ACE, the AT1 receptor, or the mineralocorticoid receptor may provide such a cardioprotective effect.