POSIBLE RESISTENCIA DE Dictyocaulus viviparus AL FENBENDAZOL EN UN BOVINO / POSSIBLE RESISTANCE OF Dictyocaulus viviparus TO FENBENDAZOLE IN A BOVINE

Se describe un caso de posible resistencia al fenbendazol en una ternera Jersey infestada por Dictyocaulus viviparus. En el municipio de Entrerríos (Antioquia, Colombia), una hembra de la raza Jersey de 6 meses de edad, presentó un serio cuadro de bronco-neumonía, el cual no mejoró con la aplicación de fenbendazol y enrofloxacina como terapia de mantenimiento. En la necropsia, se observó un número elevado de parásitos vivos compatibles con Dictyocaulus viviparus, determinando una bronquitis verminosa. Este nematodo, el cual se trata rutinariamente con fenbendazol en las fincas lecheras colombianas, ha demostrado ser resistente frente algunos bencimidazoles; finalmente, se señalan las posibles causas de esta resistencia de Dictyocaulus viviparus en la ternera Jersey.

It describe the clinical case of a possible resistance to fenbendazole in a Jersey calf infested by Dictyocaulus viviparous described. In the municipality of Entrerrios (Antioquia, Colombia) a female Jersey breed of 6 months of age, presented serious sings of bronchopneumonia. which did not improve with the application of fenbendazole and enrofloxacin as maintenance therapy. At the necropsy, a large number of live parasites compatible with Dictyocaulus viviparus were observed, determining a verminous bronchitis. This nematode, which is routinely treated with fenbendazole in Colombian dairy farms, has been proved resistance when is trated with some benzimidazoles. This specific case shows the possible causes of the Dictyocaulus viviparus resistance in Jersey calf.

Use of mTOR inhibitors in chronic heart transplant recipients with renal failure: calcineurin-inhibitors conversion or minimization?

BACKGROUND: In the last decade, mTOR inhibitors (mTOR-is) have become the cornerstone of the calcineurin inhibitor (CNI)-reduced/free regimens aimed to the preservation of post-transplant renal function. We compared utility and safety of the total replacement of calcineurin inhibitors with a mTOR-i with a strategy based on calcineurin inhibitor minimization and concomitant use of m-TOR-i. METHODS: In a retrospective multi-center cohort of 394 maintenance cardiac recipients with renal failure (GFR<60 mL/min/1.73 m(2)), we compared 235 patients in whom CNI was replaced with a mTOR-i (sirolimus or everolimus) with 159 patients in whom mTOR-is were used to minimize CNIs. A propensity score analysis was carried out to balance between group differences. RESULTS: Overall, after a median time of 2 years from mTOR-i initiation, between group differences for the evolution of renal function were not observed. In a multivariate adjusted model, improvement of renal function was limited to patients with mTOR-i usage within 5years after transplantation, particularly with the conversion strategy, and in those patients who could maintain mTOR-i therapy. Significant differences between strategies were not found for mortality, infection and mTOR-i withdrawal due to drug-related adverse events. However, conversion group tended to have a higher acute rejection incidence than the minimization group (p=0.07). CONCLUSION: In terms of renal benefits, our results support an earlier use of mTOR-is, irrespective of the strategy. The selection of either a conversion or a CNI minimization protocol should be based on the clinical characteristics of the patients, particularly their rejection risk.

Risk factors associated with cytomegalovirus infection in heart transplant patients: a prospective, epidemiological study.

BACKGROUND: The objectives of this epidemiological, prospective study were to describe the characteristics of cytomegalovirus (CMV) infection in heart transplant (HT) recipients and to identify the variables that may influence the development of CMV viremia and CMV disease in these patients. METHODS: HT recipients ≥18 years of age (n=199) were included in the study. Variables studied included CMV serostatus, immunosuppressive treatment, and administration of anti-CMV prophylaxis. RESULTS: The mean age of the population was 52 years, and 84% were males. Immunosuppressive regimens were administered as induction therapy to 92.5% of patients; 88.5% of patients received calcineurin inhibitors as maintenance therapy. Anti-CMV treatment was given to 59% of 199 patients as prophylaxis (70%), preemptive therapy (10%), or to treat CMV infection (20%). Overall, 43% of patients had at least 1 positive viremia test. No patient with a high-risk serostatus (donor+/recipient-) receiving prophylaxis developed CMV syndrome, and only 2.5% of 199 patients developed CMV invasive disease. Multivariate analysis showed that having a positive donor CMV serostatus was associated with an increased risk of developing CMV viremia (P<0.012), while use of mammalian target of rapamycin (mTOR) inhibitors was associated with a decreased risk (P=0.005). CONCLUSIONS: In a population of HT recipients, the CMV infection rate was similar to that seen in previous studies, but the progression to overt CMV disease was very low. Having a CMV-positive donor was identified as an independent risk factor for developing CMV viremia, while the use of mTOR inhibitors was protective against viremia.

Temporal trends in the use of proliferation signal inhibitors in maintenance heart transplantation: a Spanish multicenter study.

Proliferation signal inhibitors (PSI; sirolimus, everolimus) are being increasingly used in heart transplantation. We performed an observational, retrospective, multicenter study in 9 Spanish centers seeking to describe the clinical context in which a PSI was used among maintenance heart recipients and its evolution over time. We collected a cohort of 548 patients in whom a PSI was prescribed from October 2001 to March 2009. The group was divided into 3 time periods. The use of PSI steeply increased in the 2005-2006 period, remaining stable thereafter. There were no significant differences over time with regard to age, gender, or time from transplantation to the introduction of the PSI. Everolimus usage overtook sirolimus from 2005 on; currently, >90% of the subjects with PSI indications are prescribed everolimus. Compared with earlier periods, patients in the more recent period (October 2006-March 2009) showed less vascular graft disease and better basal renal function, irrespective of the primary indication for the PSI prescription. Also, skin cancer overtook solid cancer as the main type of neoplasm in patients for whom malignancy was the primary indication for the use of the PSI. The actuarial incidence of PSI withdrawal owing to adverse effects did not change significantly over time.

Steroid use in heart transplant patients in Spain in the current era: a multicenter survey.

OBJECTIVE: Steroid withdrawal (SW) from maintenance therapy in heart transplant patients is still a controversial subject. We designed a questionnaire to ascertain the attitudes and procedures of a number of Spanish heart transplant units (16) regarding the use/withdrawal of steroids as part of the immunosuppressive maintenance therapy. MATERIALS AND METHODS: We sent an 11-item questionnaire to the clinical director in charge of each unit. The questionnaire was completed and returned by 14 units. RESULTS: In 21.5% of the centers SW was performed in all patients, while 78.5% of the centers only performed SW in selected patients. In 57% of units SW was performed at 12 months posttransplantation and between 6 and 12 months in the rest. Fewer than 20% of patients were steroid-free in 46% of units while in 23% of units this proportion was >50%. In 11 units, the minimum prednisone dose administered was

Malignancy after heart transplantation: incidence, prognosis and risk factors.

The Spanish Post-Heart-Transplant Tumour Registry comprises data on neoplasia following heart transplantation (HT) for all Spanish HT patients (1984-2003). This retrospective analysis of 3393 patients investigated the incidence and prognosis of neoplasia, and the influence of antiviral prophylaxis. About 50% of post-HT neoplasias were cutaneous, and 10% lymphomas. The cumulative incidence of skin cancers and other nonlymphoma cancers increased with age at HT and with time post-HT (from respectively 5.2 and 8.9 per 1000 person-years in the first year to 14.8 and 12.6 after 10 years), and was greater among men than women. None of these trends held for lymphomas. Induction therapy other than with IL2R-blockers generally increased the risk of neoplasia except when acyclovir was administered prophylactically during the first 3 months post-HT; prophylactic acyclovir halved the risk of lymphoma, regardless of other therapies. Institution of MMF during the first 3 months post-HT reduced the incidence of skin cancer independently of the effects of sex, age group, pre-HT smoking, use of tacrolimus in the first 3 months, induction treatment and antiviral treatment. Five-year survival rates after first tumor diagnosis were 74% for skin cancer, 20% for lymphoma and 32% for other tumors.

Sirolimus as an alternative to anticalcineurin therapy in heart transplantation: experience of a single center.

We report a series of 26 heart transplant recipients with renal impairment in which sirolimus was used as the basic immunosuppresive drug (without associated calcineurin inhibitors) to avoid further nephrotoxicity. Sirolimus (trough levels 10 to 12 ng/mL, average daily dose 3 mg) was used in two settings: de novo in 7 patients with significant preexistent renal impairment and as a chronic conversion in 19 stable patients with established renal failure (creatinine level >2 mg/dL). In all de novo patients (n = 7), the renal function significantly improved. Creatinine fell from 2.95 +/- 0.9 mg/dL to 1.41 +/- 0.4 mg/dL at follow-up (P = .0017). One patient died suddenly of a massive pulmonary embolism. Only one patient experienced histologic but reversible rejection. In one patient, anemia and diarrhea prompted sirolimus withdrawal. Five patients had infectious episodes: three bacterial pneumonias, one mediastinitis, and two CMV infections. In the chronic conversion group (n = 19), the improvement was mostly limited to patients with moderate renal failure (creatinine < or =2.5 mg/dL) in which creatinine fell from 2.24 +/- 0.2 to 1.9 +/- 0.27 mg/dL, P = .009). When basal creatinine was over 2.5 mg/dL, only one third of the patients improved after conversion. Two patients died: terminal renal failure and cerebrovascular accident. There were no clinical episodes of rejection. Secondary effects prompted the discontinuation of sirolimus in five patients: two definite and one possible interstitial pneumonitis and two cases of anemia). The symptoms resolved after sirolimus withdrawal. Six patients had infection: four pneumonias, one sepsis, and one cutaneous abscess. Sirolimus is an interesting alternative to calcineurin inhibitors in selected patients with renal impairment. It prevents renal failure in de novo recipients at high risk of catastrophic renal damage and ameliorates renal dysfunction in chronic patients with moderate renal dysfunction. Given the high incidence of secondary effects, the adequate dosage and the secondary effects profile needs further study.

Pregnant adolescent and adult women have similarly low intakes of selected nutrients.

OBJECTIVE: To examine the dietary intake of pregnant adolescents during the second and third trimester of pregnancy, and to compare their nutrient intake with that of pregnant adults. DESIGN: Two 7-day food records (14 days) from subjects participating in a larger randomized clinical calcium trial: the first at 19 to 21 weeks and the second between 29 and 31 weeks gestation. Intake of energy and selected nutrients were calculated and compared with dietary standards. SUBJECTS/SETTING: Fifty-nine pregnant adolescents and 97 pregnant adults recruited from prenatal clinics at a metropolitan university hospital. STATISTICAL ANALYSES: Two sample t tests, equality of variances, and repeated measures (analysis of variance). RESULTS: There was no difference in mean nutrient intakes between the second and third trimesters. Using two 7-day food records, we found mean intakes for energy, iron, zinc, calcium, magnesium, folate, and vitamins D and E to be below recommended standards in both groups. Other nutrients examined met or exceeded reference values. Total daily intakes for energy and 11 nutrients were significantly higher in the adolescent compared to the adult diets (P < .05). These differences were not evident when nutrient values were corrected for energy, indicating that increased energy intake in the teen-aged population was contributed by nutrient-dense foods. APPLICATIONS: This study indicates the need for continued dietary monitoring of pregnant adolescents and pregnant adults, including nutrition guidance that stresses food sources of calcium, magnesium, zinc, iron, fiber, folate, and vitamins D and E, the nutrients found deficient in their diets.

Thyrotropin-like immunoreactivity in the developing chicken retina.

In this paper we analysed the presence and localisation of thyrotropin during retinal development in Gallus domesticus. Specific thyrotropin-like immunohistochemical staining was observed from the beginning of the second incubation week to one day post-hatching in chicken retina. Thyrotropin is a 28.3 KDa glycoprotein, synthesised by the anterior pituitary gland, and it is implicated in the stimulation of the synthesis and release of thyroid hormones. Until now, the action of thyrotropin has been established exclusively in hormonal terms. Recently, this glycoprotein has been localised in synaptic processes in the human retina by using a specific antiserum (Fdez-Trujillo et al., 1995). To the best of our knowledge this report is the first time that thyrotropin has been immunocytochemically demonstrated in the chicken retina. The pattern of thyrotropin-like immunoreactivity suggests that this glycoprotein could act as modulator of synaptic transmission, but it may also play a much broader role in regulating trophic functions.

The promoter of the C1 inhibitor gene contains a polypurine.polypyrimidine segment that enhances transcriptional activity.

The C1 inhibitor (C1INH) promoter is unusual in two respects: 1) It contains no TATA sequence, but instead contains a TdT-like initiator element (Inr) at nucleotides -3 to +5; 2) it contains a polypurine.polypyrimidine tract between nucleotides -17 and -45. Disruption of the Inr by the introduction of point mutations reduced promoter activity by 40%. A TATA element inserted at nucleotide -30 in the wild-type promoter and in promoter constructs containing the mutated Inr led to a 2-fold increase in basal promoter activity. Previous studies suggested that the potential hinged DNA-forming polypurine.polypyrimidine tract might be important in the regulation of C1INH promoter activity. The present studies indicate that this region is capable of such intramolecular triple helix formation. Disruption of the polypurine.polypyrimidine sequence by substitution of 5 of the 23 cytosine residues with adenine prevented triple helix formation. Site-directed mutagenesis experiments demonstrate that the regulation of promoter activity is independent of hinged DNA-forming capacity but requires an intact AC box (ACCCTNNNNNACCCT) or the overlapping PuF binding site (GGGTGGG). The C1INH gene also contains a number of potential regulatory elements, including an Sp-1 and an hepatocyte nuclear factor-1 binding site and a CAAT box. The role of these elements in regulation of the C1INH promoter was examined. Elimination of the hepatocyte nuclear factor-1 site at nucleotides -94 to -81 by truncation reduced the activity of the promoter by approximately 50%. Similarly, site-directed mutations that disrupt this site reduce promoter activity by 70%.

An integrated approach to the quantification of aortic regurgitation by Doppler echocardiography.

BACKGROUND: Although different Doppler methods have been proposed for the quantification of aortic regurgitation, no study has prospectively compared these methods with each other and their correlation with angiography. The aim of this study was to prospectively analyze the usefulness of different Doppler echocardiography parameters by testing all such parameters in each patient. METHODS: Fifty-one patients with aortic regurgitation underwent 2-dimensional and Doppler echocardiographic studies and catheterization. The following Doppler indexes were analyzed and compared with aortography. Color Doppler: (1) jet color height/left ventricular outflow tract height in parasternal long-axis view, and (2) jet color area/left ventricular outflow tract area in short-axis view. Continuous Doppler: (3) regurgitant flow pressure half-time, (4) regurgitant flow time velocity integral (in centimeters), and (5) regurgitant flow time velocity integral (in centimeters)/diastolic period (in milliseconds). Pulsed Doppler in thoracic and abdominal aorta: (6) time velocity integral of diastolic reverse flow (in centimeters), (7) time velocity integral of systolic anterograde flow/integral of diastolic reverse flow, (8) (time velocity integral of diastolic reverse flow/diastolic period) x 100, and (9) diastolic reverse flow duration/diastolic period (as a percentage). We compared these parameters with severity of regurgitation measured by angiography and classified as mild, moderate, or severe. RESULTS: The most useful parameters were (1) jet color height/left ventricular outflow tract height (correctly classified 42 of 49 patients), (2) (time velocity integral of diastolic reverse flow/diastolic period) x 100 in the thoracic aorta (correctly classified 41 of 46 patients), and (3) (time velocity integral of diastolic reverse flow/diastolic period) x 100 in the abdominal aorta (correctly classified 42 of 49 patients). Sequential integration of these 3 parameters correctly classified 96% of patients (44 of 46 patients) and was achieved in 90% of cases. CONCLUSION: An integrated combination of several Doppler parameters can quickly and accurately classify the degree of aortic regurgitation as determined by angiography.

Biological mechanisms of environmentally induced causes of IUGR.

The causes of intrauterine growth retardation (IUGR) are multiple, involving many different factors. Studies in humans and animals have shown that the maternal environment is the most important determinant of newborn weight, accounting for more similarity in birth weights of siblings than does genetic affinity. In addition to a direct relationship with the degree of maternal plasma volume expansion, many clinical factors are associated with IUGR. These factors include multiple gestation; fetal, genetic, and chromosomal anomalies (Down's syndrome and Turner's syndrome); infections such as TORCH syndrome (acronym for toxoplasmosis, rubella, cytomegalic disease, and herpes); and various maternal disorders including anemia, severe chronic asthma, chronic renal disease, heart disease and hypertension. Maternal stress factors, including narcotic addiction, cigarette smoking and chronic alcoholism, are associated with IUGR. Placental anomalies including hemangiomas, placental infarcts, single umbilical artery, and small placental size are also associated with intrauterine growth retardation. Poor nutritional status of the mother at conception and inadequate energy and protein intakes during pregnancy can also result in IUGR. Because IUGR children are not a homogeneous group, they have a broad spectrum of growth, health, and developmental outcomes. In general they have higher rates of subnormal growth, morbidity, and neurodevelopmental problems. The biomedical mechanisms reflected in nutritional, infection-related, hormonal, and metabolic parameters are not likely to be independent causative factors of IUGR, but important mediating factors of a pathologic process set in motion by other agents and insults. This paper focuses mainly on the possible negative effects that a deficient maternal diet might have on fetal development and growth.

Characterization of the IFN-gamma-responsive element in the 5' flanking region of the C1 inhibitor gene.

Treatment of a variety of cell lines with IFN-gamma leads to enhanced synthesis and secretion of C1 inhibitor (C1inh). The induction of C1inh synthesis by IFN-gamma is primarily regulated at the transcriptional level, and is controlled by elements in the 5' flanking region and the first intron of the C1inh gene. Hep3B cells transfected with reporter constructs containing truncated segments between -738 and -81 of the 5' flanking region and stimulated with IFN-gamma expressed increased levels of chloramphenicol acetyl transferase. These data as well as the data obtained from studies using constructs with mutated IFN-gamma-activated sequence (GAS) indicate that the most proximal GAS element (GAS 4) that mapped to nucleotides -126 to -118 is responsible for this IFN-gamma responsiveness. Electrophoretic mobility shift assays using GAS 4 yielded a single band that appeared within 5 min after stimulation with IFN-gamma. In competition experiments, both GAS 4 and consensus GAS probes, but not a mutated GAS probe, competed for the GAS binding protein present in Hep3B and U-937 cell extracts. The identity of the GAS binding protein was confirmed using anti-STAT-1alpha Abs in supershift assays. The results indicate that STAT-1alpha binds to GAS 4, which is the primary element in the 5' flanking region responsible for IFN-gamma induction of the C1inh gene.

Quantitative assessment of stenotic aortic valve area by using intracardiac echocardiography: in vitro validation and initial in vivo illustration.

Quantitative assessment of aortic stenosis (AS) is subject to the limitations of all current noninvasive and invasive methods. The ability to obtain a direct measure of aortic valve area with high resolution by intracardiac echocardiography (ICE) could be of great benefit to catheterized patients. To provide a fixed AS area as an ideal standard for comparison, we performed ICE in 12 sheep hearts with experimentally created AS and five human AS hearts from autopsies. ICE catheters were passed retrograde across the aortic valve, and the minimal orifice area on pullback was planimetered and compared with calibrated video imaging. The entire orifice circumference could be successfully recorded in 16 (94%) hearts. Orifice area from ICE correlated well with actual values (r=0.98; standard error of the estimate [SEE] = 0.06 cm2). To illustrate the applicability in vivo, two canine models and 10 patients with AS were studied. The limiting orifice could be imaged in both animals and in 8 of 10 patients, in whom values agreed well with invasive data (r= 0.95; SEE = 0.04 cm2). ICE can therefore accurately measure AS orifice area in vitro; it can be applied in vivo as well. These validation studies laid the foundation for subsequent clinical studies and applications.

Quantitative three-dimensional reconstruction of left ventricular volume with complete borders detected by acoustic quantification underestimates volume.

Recently a new acoustic-quantification (AQ) technique has been developed to provide on-line automated border detection with an integrated backscatter analysis. Prior studies have largely correlated AQ areas with volumes without direct comparison of volumes for agreement. By using complete AQ-detected borders as the input to a validated method for three-dimensional echocardiographic (3DE) reconstruction, we can compare an entire cavity volume measured with the aid of AQ against a directly measured volume. This would also explore the possibility of applying AQ to 3DE reconstruction to reduce tracing time and enhance routine applicability. To compare reconstructed volumes with actual values in a stable standard allowing direct volume measurement, the left ventricles of 13 excised animal hearts were studied with a 3DE system that automatically combines two-dimensional (2D) images and their locations. Intersecting 2D views were obtained with conventional scanning and AQ imaging, with gains optimized to permit 3D reconstruction by detecting the most continuous AQ borders for each view, with maximal cavity size. Reconstruction was performed with manually traced central endocardial reflections and AQ-detected borders visually reproduced the left ventricular shapes; the AQ reconstructions, however, were consistently smaller. The reconstructed left ventricular (LV) volumes correlated well with actual values by both manual and AQ techniques (r = 0.93 and 0.88, with standard errors of 2.3 cc and 2.0 cc, p = not significant [NS]). Agreement with actual values was relatively close for the manually traced borders (y = 0.93x + 0.68, mean difference = -0.8 +/-2.2 cc). AQ-derived reconstructions consistently underestimated LV volume by 39 +/- 10% (y = 0.62x-0.09, mean difference = -7.8 +/- 3.0 cc, different from manually traced and actual volumes by analysis of variance [ANOVA], F = 69, p<0.00001). The AQ-detected threshold signal was displaced into the cavity, and volume between walls and false tendons was excluded, leading to underestimation, which increased with increasing cavity volume (r = 0.76). The AQ technique can therefore be applied to 3DE reconstruction, providing volumes that correlate well with directly measured values in a stable in vitro standard, minimizing observer decisions regarding manual border placement after image acquisition. However, when the complete borders needed for 3D reconstruction are used, absolute volumes are underestimated with current algorithms that integrate backscatter and displace the detected threshold into the ventricular cavity.

Intracardiac echocardiography: in vitro and in vivo validation for right ventricular volume and function.

To determine the feasibility and accuracy of intracardiac ultrasonography (ICUS) for the measurement of right ventricular (RV) volumes and function, a 10 MHz ICUS catheter was used in an in vitro and in vivo model. In the in vitro study, 16 sheep hearts were imaged. Sequential cross-sectional images from RV apex to base were recorded during a calibrated pullback. Volumes were calculated by applying Simpson's algorithm. ICUS-obtained volumes correlated well with actual volumes (standard error of estimate [SEE] = 2.3 ml, r = 0.98). For the in vivo study, a beating-heart canine model was used (31 hemodynamic stages in six dogs). Actual volumes were measured by an intracavitary balloon connected to an external column. Sequential cross-sectional images were recorded during the ICUS catheter pullback from apex to base of the RV, and volumes calculated by Simpson's algorithm. Good correlations were observed between ICUS and actual values for diastolic (SEE = 4.1 ml, r = 0.97), systolic (SEE = 3.4 ml, r = 0.96), and ejection fraction (SEE = 3.1%, r = 0.87) values. This new technique can accurately quantitate RV volumes, can function both in vitro and in vivo, and has the potential for increasing applications to questions of clinical and research interest.