Use of mycophenolate in ANCA-associated renal vasculitis: 13 years of experience at a university hospital.

INTRODUCTION: Standard therapy with corticosteroids (CS) and cyclophosphamide (CYC) followed by azathioprine has been shown to improve renal and patient survival in ANCA-associated renal vasculitis (rAAV). Mycophenolate mofetil (MF) has been progressively introduced for the treatment of rAAV in the last years because of its immunosuppressive efficacy combined with a lower toxicity profile. In this study, we retrospectively analyse the results of the introduction of MF for maintenance and induction therapy in rAAV in our institution from 2001 to 2013. RESULTS: We reported 67 patients treated with MF as a maintenance treatment, divided by baseline serum creatinine (>500 µmol/L: Group 1 and <500 µmol/L: Group 2) and treatment schedule. Twenty-nine of the 67 patients were also treated with MF as induction treatment, mostly in Group 2. During the follow-up (2 years after the diagnosis) creatinine levels for serum glomerular filtration rate, ANCA titres, C-reactive protein and percentage of haematuria decreased in all groups. In Group 2, parameters and also relapse rates were similar at 24 months in patients treated with CYC or MF as an induction treatment (Subgroups 2a and 2b, respectively). Median dose of MF in maintenance treatment was 1000 mg daily and prednisone dose was tapered to 10 mg daily from Month 3. After 24 months, 82% of patients remained on MF therapy, 18% had discontinued the treatment, seven of them due to medical indication and two because of gastrointestinal intolerance. The percentage of patients that started renal replacement therapy was irregular in Group 1 depending on the subgroup (25-100%), and 10% in Group 2. Adverse effects, such as neutropenia, infections and neoplasia, were more prevalent in groups treated with CYC. CONCLUSION: In conclusion, in our patients with rAAV, MF demonstrated to be an effective and well-tolerated option for maintenance treatment. As an induction treatment, MF seems to be similar to CYC for patients with moderate renal failure in the diagnosis.

In vivo therapeutic efficacy of intra-renal CD40 silencing in a model of humoral acute rejection.

The humoral branch of the immune response has an important role in acute and chronic allograft dysfunction. The CD40/CD40L costimulatory pathway is crucial in B- and T- alloresponse. Our group has developed a new small interfering RNA (siRNA) molecule against CD40 that effectively inhibits its expression. The aim of the present study was to prevent rejection in an acute vascular rejection model of kidney transplant by intra-graft gene silencing with anti-CD40 siRNA (siCD40), associated or not with sub-therapeutic rapamycin. Four groups were designed: unspecific siRNA as control; sub-therapeutic rapamycin; siCD40; and combination therapy. Long-surviving rats were found only in both siCD40-treated groups. The CD40 mRNA was overexpressed in control grafts but treatment with siCD40 decreased its expression. Recipient spleen CD40+ B-lymphocytes were reduced in both siCD40-treated groups. Moreover, CD40 silencing reduced donor-specific antibodies, graft complement deposition and immune-inflammatory mediators. The characteristic histological features of humoral rejection were not found in siCD40-treated grafts, which showed a more cellular histological pattern. Therefore, the intra-renal effective blockade of the CD40/CD40L signal reduces the graft inflammation as well as the incidence of humoral vascular acute rejection, finally changing the type of rejection from humoral to cellular.

Under-recognized renal insufficiency in hospitalized patients: implications for care.

BACKGROUND: The consequences of undetected low glomerular filtration rate (GFR) are important in hospitalized patients who receive potentially nephrotoxic drugs or undergo major surgery. This study estimated the prevalence of estimated GFR (eGFR) <60mL/min/1.73m(2) in hospitalized patients. METHODS: This cross-sectional descriptive study included 14,658 adults hospitalized at 10 centers in Spain. Serum samples were analyzed for hemoglobin, creatinine, albumin and urea nitrogen. eGFR was estimated using Modification of Diet in Renal Disease (MDRD) 4 or MDRD IDMS, and MDRD 6 when serum albumin and BUN were included (n=8611). Individuals were classified as having GFR>or=60mL/min/1.73m(2), stages 3, 4 and 5 (GFR 30-59, 15-29 and <15mL/min/1.73m(2), respectively). Additionally, stages 3a and 3b (GFR 45-59 and 30-44mL/min/1.73m(2), respectively) were assessed. RESULTS: MDRD 4 eGFR showed that 28.3% of patients had renal insufficiency stages 3-5 and 14.2% had stages 3b, 4 or 5, which represents important-severe renal deterioration. Forty-three percent of patients with stages 3-5 had hemoglobin or=60mL/min/1.73m(2). A good correlation was observed between eGFR MDRD 4 and MDRD 6. CONCLUSIONS: A high percentage of hospitalized patients in Spain have deteriorated renal function stages 3-5. Using eGFR equations to assess eGFR could identify more hospitalized patients with renal insufficiency, potentially leading to improved care.

Population pharmacokinetics of high dose ibuprofen in cystic fibrosis.

AIMS: To evaluate ibuprofen population pharmacokinetics in a large series of data collected in children with cystic fibrosis (CF) treated with high doses of ibuprofen (59 patients; 2-18 years), and to identify the main causes responsible for the considerable interindividual variability in ibuprofen serum levels. METHODS: Blood samples were collected during routine clinical care; serum ibuprofen concentrations were determined by HPLC. Fitting of the concentration/time data to a one compartment kinetic population model was performed by a non-linear mixed effect regression method. RESULTS: Body weight, dose, and ibuprofen dosage form (lysinate salt or the free acid form), for elimination clearance (CL/F); and body weight, dose, and fasting status for the apparent distribution volume (Vd/F) proved to be the covariates with influence in the model. The four factors identified helped to explain part of the interindividual variability observed, but the remaining unexplained variability made therapeutic drug monitoring absolutely essential.

[Anatomopathological and biochemical correlation of lesions produced by standard and irrigated 4 mm radiofrequency catheters]. / Correlación anatomopatológica y bioquímica de las lesiones producidas por la radiofrecuencia con catéteres estándar e irrigados de 4 mm.

INTRODUCTION AND OBJECTIVES: The influence on the size of radiofrequency lesions by cooling of the tip of the electrode remains unclear. Moreover, the possible effects of two different cooling systems, closed and open, have not been well differentiated. We designed this study to compare both systems of irrigated-tip catheters and the lesions produced with standard 4 mm catheters and also to evaluate the pathological and biochemical marker release correlation (cardiac troponin I) in an experimental model. METHODS: The study was performed in 20 pigs. Applying between 1-8 radiofrequency pulses, at a power of 15, 25 or 50 watts, for 15-60 seconds to each animal. After 7 days, the pigs were sacrificed for anatomopathological study. RESULTS: A total of 54 lesions were produced, 25 with standard catheters and 29 with irrigated catheters. The mean volume of the lesions produced with standard catheters was 146 +/- 110 microl and with irrigated-tip catheters 856 +/- 864 microl (p < 0.001). Peak values of cardiac troponin I were also higher for irrigated catheters (18 +/- 15 ng/ml) than for standard (6.5 +/- 3 ng/ml). The correlation between the size of the lesion and the levels of cardiac troponin I were 0.86 and 0.79 with the standard and irrigated-tip catheters, respectively. The incidence of cratering was higher with standard catheters (60%) than with irrigated (27%). CONCLUSIONS: The lesions produced with an irrigated catheter are greater than those observed with standard catheters. The mean peak value of postablation cardiac troponin demonstrate a good correlation with the real size of the necrosis.

Biochemical markers and cardiac troponin I release after radiofrequency catheter ablation: approach to size of necrosis.

BACKGROUND: We designed this study to determine the value of serum levels of several cardiac markers in patients who underwent radiofrequency ablation and to establish the utility of cardiac troponin I (cTnI). After radiofrequency ablation there is always a small localized endomyocardial necrosis. The volume of the necrosis may be estimated by the rise of several biochemical marker levels, classically creatinine kinase (CK) and CK-MB. cTnI is a newly available biochemical marker with a high cardiac specificity. METHODS AND RESULTS: We analyzed the data from 51 patients who underwent radiofrequency ablation and from 16 control patients who underwent an electrophysiologic study without ablation. The levels of CK, CK-MB mass, cTnI, and myoglobin were compared with clinical findings, ST-T wave abnormalities, and the presence of arrhythmias. The study shows that there is a higher release of cTnI compared with the standard markers CK, CK-MB, and myoglobin. A pathologic value of cTnI was found in 92% of the patients of the ablation group. CK-MB had a lower sensitivity (63%). The area under the receiver operating characteristic curve for cTnI was 0.9375, significantly superior to the other biochemical markers (P <.05). We found a moderate level of correlation between the number of radiofrequency pulses and cardiac cTnI release (r = 0.69, P <.0001). CONCLUSIONS: The serum level of cTnI detects the minor myocardial damage produced by radiofrequency ablation. This would be useful information to have in patients who might have the potential for other ischemic events. The other biochemical or ablation parameters usually reported, including the radiofrequency ablation parameters, have no good correlation with the size of the myocardial necrosis. Therefore we suggest that monitoring of cTnI is the best way to detect and quantify the size of myocardial necrosis created by radiofrequency ablation.

Cardiac troponin I and minor cardiac damage: biochemical markers in a clinical model of myocardial lesions.

Radiofrequency (RF) catheter ablation is the curative treatment of choice for many cardiac arrhythmias. After RF ablation there is always a small localized endomyocardial necrosis, necessary to abolish the arrhythmia. We designed this study to determine the serum concentrations of several cardiac markers in patients who underwent RF catheter ablation. The study shows a higher frequency of increase of serum cardiac troponin I (cTnI) than of creatine kinase (CK), the CK MB isoenzyme (CK-MB), or myoglobin. A pathological value of cTnI was found in 47 of 51 patients (92%) in the ablation group. The area under the ROC curve for cTnI was 0.9375, significantly higher than for the other biochemical markers (0.86, 0.76, and 0.75 for CK-MB, myoglobin, and CK, respectively), with P <0.05. We conclude that the serum concentration of cTnI is the best biochemical marker for detecting the minor myocardial damage produced by RF ablation.

[Antiretroviral therapy. Announcement of the Advisory Committee of the Chilean Society of Infectology on AIDS]. / Terapia anti retroviral. Pronunciamiento del Comité Consultivo de SIDA de la Sociedad Chilena de Infectología.

There are treatments to induce the long term suppression of viral replication and that delays the progression of HIV disease. To be effective, these treatments require the uninterrupted use of a combination of drugs (ideally three), patients must be highly compliant, must be instituted in early stages of the disease and drugs must be used for prolonged periods and given by specialists. These treatments are indicated in all symptomatic patients and in those with early immunologic deterioration or high viral load. Recent infection and acute primary retroviral infections should also be considered for treatment. The treatment sponsored and financed by the ministry of health for its beneficiaries is insufficient at this time, since it is received by a minority of eligible patients due to budgetary reasons, and only two drugs are given which is considered such optimal by most experts. The committee considers that the responsibility for financing, providing and delivering these treatments in proper combination and dosages exceeds the duty of the Ministry of Health and should include all the involved parties. However, the state and its official institutions have a special responsibility to provide with adequate treatments to the poorer segments of our population. They also should promote, supervise and control the proper access of the rest of the population to efficient treatments. The committee also considers that the efforts to prevent new infections must not be neglected and that individuals under successful treatment should not consider themselves as non infectious.

Increase with age of serum lipid peroxides: implications for the prevention of atherosclerosis.

There is considerable support for the concept that oxygen free radicals and related lipid peroxides play a key role in the pathogenesis of normal senescence and of age-related chronic degenerative diseases, including atherosclerosis. This has led to a great deal of interest regarding peroxidized LDL, which seems to be more atherogenic than LDL. In contrast, the relationship of total serum or plasma lipid peroxides (which also have a marked atherogenic action) with both aging and atherogenesis are not well understood. In view of the above, we have determined the level of serum lipid peroxide (expressed as thiobarbituric acid reactive substances) in a sample of 100 healthy men and women ranging in age from 20 to 70 years. Our data show that there is an age related increase in the concentration of lipid peroxide, with men showing higher or about equal values than women until about 60 years, after which age women show the higher values. Our data also suggest that in certain men and women, aging is linked to a decline in the competence of the oxyradical-detoxifying mechanisms, which results in increased serum lipid peroxidation. Further research is needed to find out if lowering the serum peroxide levels of aging subjects by diet supplementation with antioxidants will decrease that risk. An adequate intake of antioxidants seems especially indicated in post-menopausal women because of their apparent greater sensitivity to age related oxygen stress.

[Evaluation of biochemical markers of myocardial lesion after radiofrequency ablation. Value of troponin I]. / Evaluación de marcadores de lesión miocárdica tras la ablación con radiofrecuencia. Utilidad de la troponina I.

INTRODUCTION AND OBJECTIVES: Radiofrequency catheter ablation is the curative treatment of choice for many cardiac arrhythmias. After radiofrequency ablation there is always a localized endomyocardial necrosis, which is necessary to eliminate the arrhythmia. The volume of the necrosis may be evaluated by the rise of several biochemical markers, classically CK and CK-MB. However, the sensitivity and specificity of these markers are not optimal and are probably less than ideal for this purpose. Cardiac Troponin I (cTnI) is a newly available biochemical marker available, with a high cardiac specificity. We designed this study in order to determine the value of serum levels of several cardiac markers in patients who underwent radiofrequency catheter ablation and to establish the utility of cTnI. METHODS: We analyzed the data from 51 patients who underwent radiofrequency ablation and from 16 control patients. In respect to the ablation target, we included in the study 14 left accessory pathways, 7 right accessory pathways, 12 atrioventricular nodal reentry tachycardia, 5 ventricular tachycardia and 13 atrial flutter or fibrillation. The levels of CK, CK-MB, cTnI, and myoglobin were compared with clinical findings, ST-T wave abnormalities and the presence of arrhythmias after ablation. To evaluate the diagnostic capability for each biochemical marker we used the ROC curves. RESULTS: A pathological value of cTnI was found in 47 out of 51 (92%) patients in the ablation group. CK-MB had a lower sensitivity (63%). The sensitivity for the other biochemical markers ranged from 30% for CK to 67% for Myoglobin. The area under the ROC curve for cTnI was 0.9375, significantly superior to the other biochemical markers (0.86, 0.76, 0.75 for MB, Myoglobin, CK respectively) (p < 0.05). The lowest cTnI released was found in patients after nodal reentry tachycardia ablation and the highest after atrial flutter ablation. cTnI increased above normal values in 4 patients in the control group (patients who underwent an electrophysiological study without catheter ablation). We found a moderate level of correlation between the number of radiofrequency pulses and cardiac cTnI release (r = 0.69; p < 0.0001). The correlation was different in each target, ranging between r = 0.25 (p = NS, 0.43) for atrial flutter and fibrillation to r = 0.99 (p < 0.0001) for ventricular tachycardia. CONCLUSIONS: cTnI had the greatest sensitivity (92%) for detecting minor myocardial damage. Thus, we can conclude that the serum level of cTnI detects the minor myocardial damage produced by radiofrequency ablation.

New evidence that serum beta(2)-microglobulin behaves as a biological marker of bone remodelling in women.

Having observed that serum beta(2)-microglobulin concentration correlates with serum tartrate-resistant acid phosphatase (TRAP) concentration in postmenopausal osteoporosis, and that metacarpal endosteal diameter is dependent on bone resorption, we correlated the two biochemical parameters with the radiographic parameter to determine if beta(2)-microglobulin behaves like a biological marker of bone remodelling. In 105 women (mean age 68 +/- 4 years) consisting of 60 normal postmenopausal women and 55 osteoporotic postmenopausal women, there was a significant positive correlation between metacarpal endosteal diameter and these two biochemical values (r = 0.66 with beta(2)-microglobulin and r = 0.68 with TRAP in the osteoporotic postmenopausal women; r = 0.48 with beta(2)-microglobulin and r = 0.56 with TRAP in the normal postmenopausal women; P < 0.001 for all comparisons). All three measurements were significantly higher (P < 0.001) in the osteoporotic postmenopausal women than in the normal postmenopausal women. These findings show that serum beta(2)-microglobulin behaves like a biological marker of remodelling.

[Alcohol consumption and family: a descriptive study in adolescents]. / Consumo de alcohol y familia: un estudio descriptivo en adolescentes.

AIM: To study abnormal alcohol ingestion among parents and family dysfunction of pregnant and non pregnant teenagers. SUBJECTS AND METHODS: Pregnant and non pregnant girls from 12 to 18 years old consulting in the Teenager Health Unit of a public hospital outpatient clinic were studied. Their degree of instruction attained, marital status, social behavior, alcohol, drug intake and history of child abuse was recorded. The level of instruction, marital status, alcohol ingestion and work stability of their fathers was also studied. RESULTS: One hundred sixteen pregnant and 60 non pregnant teenagers were studied. The fathers of pregnant girls had a higher level of alcohol consumption, more civil irregularities and a higher level of family dysfunction. Among these girls, a higher frequency of neurological abnormalities and fetal alcohol syndrome was observed. They had also a lower educational level and a higher degree of alcohol and drug use. CONCLUSIONS: Alcohol consumption among parents leads to family dysfunction and has adverse physical, intellectual and social consequences in the offspring.

Beta-2-microglobulin in diseases with high bone remodeling.

Beta2-microglobulin has been observed to behave as a biological marker of bone remodeling. We measured beta2-microglobulin and tartrate-resistant acid phosphatase (TRAP), a specific biological marker of bone remodeling, in 225 women: healthy premenopausal controls, healthy postmenopausal control, and patients with diseases characterized by enhanced bone turnover (postmenopausal osteoporosis, primary hyperparathyroidism, primary hyperthyroidism, polyostotic Paget's bone disease), and in other Paget's group before and after calcitonin treatment. Beta2-microglobulin levels differed significantly between the healthy premenopausal women (n = 20) compared with all the other groups. However, beta2-microglobulin levels did not differ significantly between healthy postmenopausal women (n = 38) and patient's with Paget's bone disease (n = 40)(P = 0.5095), or between women with postmenopausal osteoporosis (n = 30) and women with hyperthyroidism (n = 20)(P = 0.7890). TRAP concentrations differed significantly in all the groups paired except for women with Paget's bone disease and women with either hyperparathyroidism or hyperthyroidism (P = 0.5179 and 0.6993, respectively); likewise, TRAP levels did not differ significantly between the women with hyperparathyroidism and those with hypothyroidism (P = 0.7804). After calcitonin treatment, there was a 22% increase in beta2-microglobulin, a 17% decrease in TRAP, and a 39% decrease in alkaline phosphatase, all of which were significant at P < 0.0001. Our findings indicate that serum beta2-microglobulin, like osteocalcin, behaves as a biological marker of remodeling in a number of diseases with enhanced bone remodeling but not in Paget's bone disease.

Zinc, biochemical markers of nutrition, and type I osteoporosis.

Having observed previously that the reduction of levels of biological markers of nutrition in postmenopausal osteoporosis may be related to zinc deficiency, we measured plasma and urinary zinc concentrations in 30 women with postmenopausal osteoporosis and in 30 healthy postmenopausal women who served as controls. Plasma zinc levels did not differ between groups, but urinary zinc excretion was significantly higher in the women with postmenopausal osteoporosis (p = 0.002). The relation between total body bone mineral content corrected for body weight (TBBMC/W) and markers of nutrition was significant (multiple regression analysis: p < 0.0001) in the women with postmenopausal osteoporosis but not in the healthy postmenopausal controls. Likewise, the relation between TBBMC/W and plasma and urinary zinc levels also was significant in the women with postmenopausal osteoporosis but not in the controls (multiple regression analysis: p = 0.0022). Neither group showed any correlation between plasma or urinary zinc concentrations and levels of biological markers of nutrition. Urinary zinc concentration correlated significantly with serum tartrate-resistant acid phosphatase level (simple linear regression analysis: r = 0.583, p < 0.001) in the women with postmenopausal osteoporosis but not in controls. TBBMC correlated with urinary zinc concentration significantly in the women with postmenopausal osteoporosis (simple linear regression: r = 0.567, p = 0.0015), but the correlation was nonsignificant in healthy postmenopausal controls. These findings indicate that the elevation of urinary zinc elimination in osteoporosis is dependent on bone resorption.

beta 2-Microglobulin in Paget's bone disease.

On the basis of earlier findings of increased serum beta 2-microglobulin concentration in women with postmenopausal osteoporosis, we decided to study serum beta 2-microglobulin concentration in other bone diseases. In 28 patients with untreated Paget's bone disease, serum beta 2-microglobulin concentration was normal (1.49 +/- 0.41 mg/liter versus 1.36 +/- 0.21 mg/liter in 42 control subjects, P = ns), a finding that contradicts reports in the literature. We found that serum beta 2-microglobulin concentration was related negatively and significantly (r2 = -0.154, P = 0.0354) with serum total alkaline phosphatase concentration, but not with serum tartrate-resistant acid phosphatase concentration (p = ns). Urinary elimination of beta 2-microglobulin was lower in the patients with Paget's disease than in the controls (34 +/- 28 versus 120 +/- 21 mg/liter, P < 0.001). These findings suggest that beta 2-microglobulin behaves similarly to osteocalcin (BGP) in Paget's bone disease and that its concentration remains within normal levels perhaps because of the rate of reuptake of beta 2-microglobulin in bone neoformation.

Beta 2-microglobulin in postmenopausal osteoporosis.

The so-called bone-derived growth factor, or beta 2-microglobulin, has a regulatory function in bone metabolism, stimulating osteoclastic activity. Osteoclastic activity is enhanced in postmenopausal osteoporosis, suggesting that beta 2-microglobulin concentration may also be increased in this disease. beta 2-microglobulin concentration was found to be raised (P < 0.001) in 30 women with postmenopausal osteoporosis as compared with 30 normal women of similar age; tartrate-resistant acid phosphatase concentration also was raised (P < 0.001), and total body bone mineral content was decreased (P < 0.001). Linear regression analysis revealed a highly negative correlation result between total body bone mineral content and beta 2-microglobulin (r = 0.577, P < 0.001), and a positive correlation result between beta 2-microglobulin and tartrate-resistant acid phosphatase concentration (r2 = 0.806, P < 0.001). These findings, and the stimulatory effect of beta 2-microglobulin on osteoclastic and osteoblastic activity, suggest that beta 2-microglobulin may play an important role as a local regulatory factor in the pathogenesis of postmenopausal osteoporosis.

Screening of cDNA libraries with oligonucleotides as applied to signal transducing G proteins, receptors and effectors.

Screening of cDNA libraries constructed in phage or plasmids with oligonucleotide probes has become one of the preferred cloning techniques with the least number of false positive failures. In this article we present our current protocols for designing the procedure to detect cDNA inserts and isolate them. We illustrate with primary screens for G protein subunits and membrane receptors.