Safety and effectiveness of direct-acting antiviral drugs in the treatment of hepatitis C in patients with inflammatory bowel disease

BACKGROUND AND AIMS

Hepatitis C virus (HCV) management in Inflammatory Bowel Disease (IBD) is uncertain. The ECCO guidelines 2021 recommended HCV treatment but warn about the risk of IBD reactivation. We aimed to evaluate 1) the effectiveness and safety of direct-acting antivirals (DAAs) in IBD; 2) the interaction of DAAs with IBD drugs.

METHODS

Multicentre study of IBD patients and HCV treated with DAAs. Variables related to liver diseases and IBD, as well as adverse events (AEs) and drug interactions, were recorded. McNemar's test was used to assess differences in the proportion of active IBD during the study period.

RESULTS

We included 79 patients with IBD and HCV treated with DAAs from 25,998 IBD patients of the ENEIDA registry. Thirty-one (39.2 %) received immunomodulators/biologics. There were no significant differences in the percentage of active IBD at the beginning (n = 11, 13.9 %) or at the 12-week follow-up after DAAs (n = 15, 19 %) (p = 0.424). Sustained viral response occurred in 96.2 % (n = 76). A total of 8 (10.1 %) AEs occurred and these were unrelated to activity, type of IBD, liver fibrosis, immunosuppressants/biologics, and DAAs.

CONCLUSIONS

We demonstrate a high efficacy and safety of DAAs in patients with IBD and HCV irrespective of activity and treatment of IBD.

Pandemic Precarity: COVID-19's Impact on Mexican and Central American Immigrant Families

Objective

The study examines the association of gender, parenthood, and marriage with reports of perceived pandemic precarity among Mexican and Central American immigrants during the COVID-19 pandemic (Fall 2020) to understand predictors of vulnerability in periods of crisis.

Background

Latinos/as, immigrants, parents, and women have faced significant challenges during the COVID-19 pandemic. Family structure, along with social expectations for gender (i.e., self-sacrificing femininity for women and hegemonic masculinity for men), parenthood, and marriage may explain perceptions of pandemic precarity - defined as the material deprivation and economic anxiety resulting from the COVID-19 pandemic.

Method

This study used data from the Hispanic COVID-19 Rapid Response Study (n=400), a follow-up of the VidaSana Study of Mexican and Central American immigrants, to examine how family structure is associated with pandemic precarity (i.e., food, housing, and economic insecurity). Using linear regression models, average marginal effects (AMEs), and tests for group differences we investigate the independent and interactive effects of gender, parenthood, and marriage on pandemic precarity.

Results

Men and parents reported the highest pandemic precarity. Fathers reported higher pandemic precarity than mothers. For men, marriage is associated with greater precarity, and for women, marriage is associated with less precarity, yet marriage increased precarity for those without children.

Conclusion

We discuss the importance and implications of examining gender along with family structure to understand how immigrant families were faring in response to the pandemic.

Skin Tone and Mexicans’ Perceptions of Discrimination in New Immigrant Destinations

Colorism literature examines how skin tone—alongside prototypical group features and hairstyles—correlates with socioeconomic, health, and political outcomes. Yet few studies have explicitly operationalized how skin tone shapes Latinos’ experiences of racialization in “new” U.S. destinations. Here, we draw on a large, representative sample of Mexican immigrants (N = 500) living in two large metropolitan areas (Atlanta and Philadelphia) to investigate how skin tone shapes their perceptions about the frequency and sources of discrimination. Even after controlling for demographic, economic, and immigration–specific factors, including ethnoracial self–identification, we show darker skin tone is significantly associated with higher reports of racial discrimination, discrimination specifically from U.S.-born Whites, and a stronger tendency to struggle internally in response. Together, these results support colorism literature’s argument that skin tone is distinct from race and offer new insights into how skin tone shapes the lived experiences of Mexican immigrants outside the U.S. Southwest.

Prognostic gene expression signature for high-grade serous ovarian cancer

BACKGROUND

Median overall survival (OS) for women with high-grade serous ovarian cancer (HGSOC) is ∼4 years, yet survival varies widely between patients. There are no well-established, gene expression signatures associated with prognosis. The aim of this study was to develop a robust prognostic signature for OS in patients with HGSOC.

PATIENTS AND METHODS

Expression of 513 genes, selected from a meta-analysis of 1455 tumours and other candidates, was measured using NanoString technology from formalin-fixed paraffin-embedded tumour tissue collected from 3769 women with HGSOC from multiple studies. Elastic net regularization for survival analysis was applied to develop a prognostic model for 5-year OS, trained on 2702 tumours from 15 studies and evaluated on an independent set of 1067 tumours from six studies.

RESULTS

Expression levels of 276 genes were associated with OS (false discovery rate < 0.05) in covariate-adjusted single-gene analyses. The top five genes were TAP1, ZFHX4, CXCL9, FBN1 and PTGER3 (P < 0.001). The best performing prognostic signature included 101 genes enriched in pathways with treatment implications. Each gain of one standard deviation in the gene expression score conferred a greater than twofold increase in risk of death [hazard ratio (HR) 2.35, 95% confidence interval (CI) 2.02-2.71; P < 0.001]. Median survival [HR (95% CI)] by gene expression score quintile was 9.5 (8.3 to -), 5.4 (4.6-7.0), 3.8 (3.3-4.6), 3.2 (2.9-3.7) and 2.3 (2.1-2.6) years.

CONCLUSION

The OTTA-SPOT (Ovarian Tumor Tissue Analysis consortium - Stratified Prognosis of Ovarian Tumours) gene expression signature may improve risk stratification in clinical trials by identifying patients who are least likely to achieve 5-year survival. The identified novel genes associated with the outcome may also yield opportunities for the development of targeted therapeutic approaches.

Impact of immune-mediated diseases in inflammatory bowel disease and implications in therapeutic approach

Inflammatory bowel diseases (IBD) belong to the group of immune-mediated diseases (IMIDs). The effect of associated IMIDs in the prognosis in IBD is nowadays unknown. To describe IMIDs associated to IBD patients and evaluate differences linked to the presence or absence of IMIDs. A unicentric retrospective descriptive study was designed. A cohort of 1,448 patients were categorized according to the presence of IMIDs. Clinical characteristics were obtained from IBD database. Univariate and multivariate analysis were performed. 385 patients were diagnosed with associated IMIDs while 1,063 had no associated IMIDs. A prevalence of 26.6% IMIDs associated to IBD was observed. Asthma, skin psoriasis and rheumatoid diseases were most commonly found. Factors associated to the presence of IMIDs were women (OR 1.48; 95 CI 1.17–1.87) and Crohn’s disease (OR 1.35; 95 CI 1.07–1.70). Patients with associated IMIDs required more immunomodulator (OR 1.61; 95 CI 1.27–2.43) and biological treatment (OR 1.81; 95 CI 1.47–2.43). More surgical risk was observed in multivariate analysis in those patients diagnosed with IMIDs prior to the onset of IBD (OR 3.71; 95% CI 2.1–6.56). We considered the presence of IMIDs a poor prognostic factor and suggest a closer monitoring of these patients.

Attenuation of pharmaceuticals and their transformation products in a wastewater treatment plant and its receiving river ecosystem

Pharmaceuticals are designed to improve human and animal health, but may also be a threat to freshwater ecosystems, particularly after receiving urban or wastewater treatment plant (WWTP) effluents. Knowledge on the fate and attenuation of pharmaceuticals in engineered and natural ecosystems is rather fragmented, and comparable methods are needed to facilitate the comprehension of those processes amongst systems. In this study the dynamics of 8 pharmaceuticals (acetaminophen, sulfapyridine, sulfamethoxazole, carbamazepine, venlafaxine, ibuprofen, diclofenac, diazepam) and 11 of their transformation products were investigated in a WWTP and the associated receiving river ecosystem. During 3 days, concentrations of these compounds were quantified at the influents, effluents, and wastage of the WWTP, and at different distances downstream the effluent at the river. Attenuation (net balance between removal and release from and to the water column) was estimated in both engineered and natural systems using a comparable model-based approach by considering different uncertainty sources (e.g. chemical analysis, sampling, and flow measurements). Results showed that pharmaceuticals load reduction was higher in the WWTP, but attenuation efficiencies (as half-life times) were higher in the river. In particular, the load of only 5 out of the 19 pharmaceuticals was reduced by more than 90% at the WWTP, while the rest were only partially or non-attenuated (or released) and discharged into the receiving river. At the river, only the load of ibuprofen was reduced by more than 50% (out of the 6 parent compounds present in the river), while partial and non-attenuation (or release) was observed for some of their transformation products. Linkages in the routing of some pharmaceuticals (venlafaxine, carbamazepine, ibuprofen and diclofenac) and their corresponding transformation products were also identified at both WWTP and river. Finally, the followed procedure showed that dynamic attenuation in the coupled WWTP-river system could be successfully predicted with simple first order attenuation kinetics for most modeled compounds.

Galectin-1 in stable liver transplant recipients

INTRODUCTION

The achievement of a state of tolerance and minimization of the immunosuppressive load form part of the "Holy Grail" in solid organ transplantation. Galectin-1 recently has been described to be involved in the maintenance of a tolerant environment, but there is no evidence of its role in human liver transplantation. The aim of our study was to measure the serum levels of galectin-1 in stable liver transplant recipients.

METHODS

Serum levels of galectin-1 were determined in 30 stable liver transplant recipients who had been free of rejection episodes for at least 8 years. Fifteen patients with an acute rejection episode and 34 healthy subjects were used as the control group.

RESULTS

The concentrations of galectin-1 were significantly higher in stable liver transplant recipients compared with healthy subjects and with the acute rejection group.

CONCLUSIONS

These preliminary results indicate that galectin-1 is upregulated in stable liver transplant recipients. Thus, our results extend the recent findings that galectin-1 may play an immune-suppressive role in liver transplantation. It remains to be established whether it might help to induce tolerance in liver transplantation.

Challenges and potential solutions for big data implementations in developing countries

BACKGROUND

The volume of data, the velocity with which they are generated, and their variety and lack of structure hinder their use. This creates the need to change the way information is captured, stored, processed, and analyzed, leading to the paradigm shift called Big Data.

OBJECTIVES

To describe the challenges and possible solutions for developing countries when implementing Big Data projects in the health sector.

METHODS

A non-systematic review of the literature was performed in PubMed and Google Scholar. The following keywords were used: "big data", "developing countries", "data mining", "health information systems", and "computing methodologies". A thematic review of selected articles was performed.

RESULTS

There are challenges when implementing any Big Data program including exponential growth of data, special infrastructure needs, need for a trained workforce, need to agree on interoperability standards, privacy and security issues, and the need to include people, processes, and policies to ensure their adoption. Developing countries have particular characteristics that hinder further development of these projects.

CONCLUSIONS

The advent of Big Data promises great opportunities for the healthcare field. In this article, we attempt to describe the challenges developing countries would face and enumerate the options to be used to achieve successful implementations of Big Data programs.

Local thyroid renin-angiotensin system in experimental breast cancer

An association between breast cancer and thyroid dysfunction exists although the underlying mechanisms remain to be elucidated. Numerous studies have characterized the role of thyroid hormones in controlling the synthesis and secretion of renin-angiotensin system (RAS) components, but little information is available on the putative role of the local RAS on thyroid function.

AIMS

Here we analyze several soluble and membrane-bound RAS-regulating aminopeptidase activities in thyroid gland from rats with mammary tumors and the relationship with the circulating levels of thyroid stimulating hormone (TSH) and free thyroxin (fT4).

MAIN METHODS

We analyze soluble and membrane-bound RAS-regulating aminopeptidase activities fluorometrically using their corresponding aminoacyl-β-naphthylamide as the substrate.

KEY FINDINGS

We have found in rats with mammary tumors a concomitant change of thyroid RAS-regulating enzymes and thyroid hormone production.

SIGNIFICANCE

We suggest that existence of alterations in the regulatory mechanisms mediated by the angiotensins of the local tissue RAS as a consequence of the carcinogenic process which could act alone or in combination with alterations at a higher level of regulation such as the hypothalamus-pituitary axis.

Phenotypic characterization of hereditary epithelial ovarian cancer based on a tissue microarray study

The pathologic and immunohistochemical features of familial epithelial ovarian cancers are not well understood. We have carried out a comprehensive immunohistochemical study of familial ovarian carcinomas from women with and without BRCA1 or BRCA2 mutations, in order to identify specific and/or common features among these different familial case groups (BRCA1, BRCA2 and non-BRCA1/2) and to identify markers of diagnostic value that might help to select more specific treatments. 73 familial primary ovarian carcinomas were analyzed for the expression of 40 antibodies involved in different genetic pathways using a tissue microarray. Serous carcinomas comprised the majority of all three familial case groups. On the other hand, BRCA1 and BRCA2 carcinomas have similar histopathologic features; i.e. they are often high-grade and are usually diagnosed at a more advanced FIGO stage than non-BRCA1/2 carcinomas. In our series, BRCA1 carcinomas had better clinical evolution and they also more frequently over-expressed PR and P53 than BRCA2 and non-BRCA1/2 carcinomas. Unsupervised cluster analysis and survival analysis identified ERCC1 as a potential marker of better clinical outcome for hereditary epithelial ovarian cancer.

First Report of Bacterial Canker of Kiwifruit Caused by Pseudomonas syringae pv. actinidiae in Spain

Bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae was first described in Japan and Korea and is currently an emerging disease that causes major losses in China, Italy, New Zealand, France, Portugal, and Chile. Gold kiwifruit (Actinidia chinensis), especially cvs. Jin Tao and Hort 16A, seem to be more susceptible than green kiwifruit (Actinidia deliciosa) cvs. Hayward and Summer. The bacterium affects male and female woody vines equally, with young vines being more susceptible. The most characteristic symptoms that appear in early spring are reddish orange or white exudates associated with cankers and wounds in branches and/or trunk, as well as brown leaf spots. Buds and fruits were also affected (1). In Spain, 1,132 ha of kiwifruit orchards yielded 25,285 t of fruit in 2009 (2). Most Spanish kiwifruit is cultivated in Galicia (northwest Spain), where the main cultivar is Hayward. In 2010, the first plantation of cv. Jin Tao and one plantation of cv. Summer were established in this area close to Hayward woody vine. In early spring 2011, 80% of the vines in one orchard had twigs with reddish exudates and branches and trunks as well as leaves with angular spots surrounded by yellow haloes. Isolations from both Actinidia spp. were conducted on nutrient agar with sucrose. One hundred and twelve isolates were obtained and seventy-seven were aerobic, gram negative and nonfluorescent on King's B medium. Biochemical tests performed were levan, oxidase, potato rot, arginine didhydrolase, hypersensitivity in tobacco, and utilization of 49 carbohydrates by the API 50 CH system (BioMérieux, Marcy l'Etoile, France). Three PCR protocols were used: two with pathovar-specific primers (PSAF1/PSAR2 and PSAF3/PSAR4) and one with nonspecific primers (PsITSF1/PsITSR2) (3). The results of all biochemical and molecular tests were in agreement with those expected for P. syringae pv. actinidiae. The 16S-23S region of strain EFA 37 isolated from A. deliciosa cv. Summer was sequenced (GenBank Accession No. JF815537) and had 100% sequence identity with P. syringae pv. actinidiae (GenBank Accession Nos. AY342165 and D86357). Pathogenicity tests were performed on 15 plants of A. deliciosa cv. Hayward (five plants per isolate) with the Spanish representative strain EFA 37 and compared with two reference strains isolated from both Actinidia species in Italy and five plants of an untreated control. Three buds per healthy vine were wounded with a sterile needle, inoculated with 30 to 50 μl of each bacterial suspension (10⁸ CFU/ml), sealed, and then covered with plastic. Five leaves per healthy vine were also pierced with a sterile needle and then atomized with the same suspension. Symptoms began to appear after 5 days on inoculated vines, but not on untreated control vines. The bacterium, P. syringae pv. actinidiae, was reisolated from symptomatic plants. The kiwifruit orchard with affected plants was eradicated (25 ha). To our knowledge, this is the first report of P. syringae pv. actinidiae in Spain. References: (1) EPPO Alert List. Online publication. Retrieved from http://www.eppo.org/QUARATINE/Alert_List , June, 2011. (2) Ministerio de Medio Ambiente y Medio Rural y Marino (MARM). Anuario de Estadística, Online Publication. Retrieved from http://www.marm.es/estadistica/pags/anuario/2010 , June 2011. (3) J. Rees-George et al. Plant Pathol. 59:453, 2010.

[Core needle biopsy of papillary breast lesions: impact on patient management]

OBJECTIVES

To evaluate the clinical and radiological presentations of papillary breast lesions and to evaluate the performance of core needle breast biopsy in papillary lesions.

MATERIAL AND METHODS

We retrospectively studied 55 papillary breast lesions in 46 patients aged 28 to 87 years diagnosed using core needle biopsy in the period 1994-2005. We reviewed the clinical and radiological presentations of the lesions, the findings at histological study after percutaneous biopsy, and the correlation of these findings with those of the surgical biopsy (44 cases) and/or radiological follow-up (42 cases).

RESULTS

The most common mammographic presentation was circumscribed or ill-defined, single or multiple nodules. Ill-defined lesions were significantly associated with malignancy (p < 0.05). The results of the percutaneous biopsy were: benign papillary lesion (n = 32), papillary lesion with atypia (n = 9), and malignant papillary lesion (n = 14). The diagnostic accuracy of core needle biopsy calculated from the 44 cases with surgical confirmation was: sensitivity 63%, specificity 100%, predictive positive value 100%, predictive negative value 73%, and rate of underestimation 25%. During follow-up, increased lesion size or the appearance of new lesions was seen in four patients.

CONCLUSIONS

The diagnosis can be suspected in cases of postmenopausal patients with multiple circumscribed or ill-defined, solid or mixed lesions at ultrasound study. Although the finding of an invasive malignant papillary lesion after percutaneous biopsy enables treatment to be planned, in the remaining situations (benign papillary lesion, with atypia, or carcinoma in situ) underestimation is common and the lesion should be surgically excised. Vacuum-assisted biopsy systems might improve these results.

Methylmalonic acidaemia: examination of genotype and biochemical data in 32 patients belonging to mut, cblA or cblB complementation group

Methylmalonic acidaemia (MMA) is a genetic disorder caused by defects in methylmalonyl-CoA mutase or in any of the different proteins involved in the synthesis of adenosylcobalamin. The aim of this work was to examine the biochemical and clinical phenotype of 32 MMA patients according to their genotype, and to study the mutant mRNA stability by real-time PCR analysis. Using cellular and biochemical methods, we classified our patient cohort as having the MMA forms mut (n = 19), cblA (n = 9) and cblB (n = 4). All the mut (0) and some of the cblB patients had the most severe clinical and biochemical manifestations, displaying non-inducible propionate incorporation in the presence of hydroxocobalamin (OHCbl) in vitro and high plasma odd-numbered long-chain fatty acid (OLCFA) concentrations under dietary therapy. In contrast, mut (-) and cblA patients exhibited a milder phenotype with propionate incorporation enhanced by OHCbl and normal OLCFA levels under dietary therapy. No missense mutations identified in the MUT gene, including mut (0) and mut (-) changes, affected mRNA stability. A new sequence variation (c.562G>C) in the MMAA gene was identified. Most of the cblA patients carried premature termination codons (PTC) in both alleles. Interestingly, the transcripts containing the PTC mutations were insensitive to nonsense-mediated decay (NMD).

Distinct genomic aberration patterns are found in familial breast cancer associated with different immunohistochemical subtypes

Five breast cancer subtypes have been described in sporadic breast cancer (SBC) using expression arrays: basal-like, ERBB2, normal breast-like, luminal A and B. These molecular subtypes show different genomic aberration patterns (GAPs). Recently, our group described these breast cancer subtypes in 50 non-BRCA1/2 familial tumors using immunohistochemistry assays. We extended this study to the other classes of familial breast cancer (FBC), including 62 tumors (18 BRCA1, 16 BRCA2 and 28 non-BRCA1/2), with the same panel of 25 immunohistochemical (IHC) markers and histological grade obtaining a similar classification. We combined these data with results generated by a 1 Mb BAC array-based CGH study to evaluate the genomic aberrations of each group. We found that BRCA1-related tumors are preferentially basal-like, whereas non-BRCA1/2 familial tumors are mainly luminal A subtype. We described distinct GAPs related to each IHC subtype. Basal tumors had a greater number of gains/losses, while luminal B tumors had more high-level DNA amplifications. Our data are similar to those obtained in SBC studies, highlighting the existence of distinct genetic pathways of tumor evolution, common to both SBC and FBC.

Outbreak of tularaemia in Castilla y León, Spain

In late June 2007, the Epidemiological Surveillance Network in Castilla y León, northern Spain, reported a series of cases in a rural area in the province of Palencia and in the provincial capital city of León, labelled as “fever of unknown origin”. Subsequent epidemiological investigation confirmed an outbreak of tularaemia.

Use of ultrasound for the determination of flour quality

Within the baking industry, the control of dough properties is required to achieve final product quality and consistency. Traditional methods for dough testing are slow and off-line and do not provide fundamental rheological information. There is therefore a need for the development of fast and on-line instruments capable of providing relevant data for baking. Ultrasonics provide a non-destructive, rapid and low cost technique for the measurement of physical food characteristics. In this work, the water content of dough is investigated using ultrasonic techniques. The capability of ultrasound measurements for discriminating flours for different purposes is also studied. Doughs from more than 30 flours were characterised rheologically using a Chopin Alveograph and a Brabender Extensograph. Ultrasound measurements on the doughs prepared from these flours were also performed. The measurements were correlated, showing that ultrasound was an alternative measurement method to discriminate types of flours for different purposes.

Neutron measurements in Spanish nuclear power plants with a Bonner sphere spectrometer system

Neutron spectrometric measurements with an active Bonner Sphere System (BSS) allowed us to determine the reference dosimeter values in Ascó I and II and Cofrentes (PWR, BWR) Spanish nuclear power plants. Under a request from the Spanish National Nuclear Safety Council, the UAB group was in charge of characterising the neutron fields at several measurement points (a total of 10) inside the containment building of these nuclear installations using an active BSS and a home-made MITOM unfolding code. The measurement results in the three installations confirm the presence of low-energy neutron components in almost all selected points. This developed BSS can be considered as a reference system in neutron radiation protection when defining the corresponding protocols for a correct personal dosimetry in nuclear power plant installations.

Neutron spectrometry in a PET cyclotron with a Bonner sphere system

Positron emission tomography (PET) is a non-invasive medical imaging technique normally used for diagnostic purposes to determine the location and concentration of physiologically active compounds in a human body. An unshielded cyclotron is used for PET at the Clinica Universitaria de Navarra to produce short-lived positron emitting radionuclides ((15)O, (13)N, (11)C and (18)F) by bombarding appropriate target material with proton or deuteron beams with energies up to 18 and 9 MeV, respectively. Subsequent nuclear reactions may generate undesirable neutrons that should be evaluated and controlled. In this study, the neutron measurements performed with an active and a passive Bonner sphere systems at different locations outside and inside the cyclotron vault during operation have been presented. The neutron spectrum at each location was determined with an unfolding code developed by the authors.

Persistent increase of plasma butyryl/isobutyrylcarnitine concentrations as marker of SCAD defect and ethylmalonic encephalopathy

High concentrations of butyryl/isobutyrylcarnitine (C(4)-carnitine) in plasma with increase of ethylmalonic acid (EMA) in urine point to different genetic entities, and further investigations are required to differentiate the possible underlying defect. Here we report three unrelated cases, two neurologically affected and one asymptomatic, with this abnormal metabolite pattern due either to mutations in the ETHE1 gene or to a short-chain acyl-CoA dehydrogenase (SCAD) defect.

Renin-angiotensin system-regulating aminopeptidase activities are modified in the pineal gland of rats with breast cancer induced by N-methyl-nitrosourea

OBJECTIVE

Pineal function has been considered particularly as a neuroendocrine modulator in hormone responsive tumors, like the hormone-dependent mammary tumors. The complexity of the gland function, moreover, is denoted by the presence of a local renin-angiotensin-system (RAS) that regulates melatonin biosynthesis. Classically, angiotensin II (Ang II) has been considered as the effector peptide of the RAS, but Ang II is not the only active peptide. Several of its degradation products, including angiotensin III (Ang III) and angiotensin IV (Ang IV) also possess biological functions. These peptides are formed via the activity of several aminopeptidases. Our aim is to know their role in the regulation of pineal RAS and breast cancer.

DESIGN

Aminopeptidase N (APN), aminopeptidase B (APB) and aminopeptidase A (aspartyl- and glutamyl-aminopeptidase, APA) activities are measured in the pineal gland of rats with breast cancer induced by N-methyl nitrosourea (NMU).

METHODS

Aminopeptidase activities were measured fluorimetrically using their corresponding aminoacyl-beta-naphthylamides as substrates.

RESULTS

Specific APN and APB activities in pineal gland of controls and NMU-treated rats were not modified. Aspartyl aminopeptidase activity significantly decreased in NMU-treated rats when compared with control group. On the contrary, glutamyl aminopeptidase activity did not show significant differences between groups.

CONCLUSIONS

We propose that the local RAS in pineal gland is modified in rats with breast cancer induced by NMU through the inhibition of AspAP activity, which may lead to increased levels of Ang II. Ang II could be responsible of the overproduction of melatonin, supporting a mechanism to restrain the promotion and/or progression of breast cancer.

[Situation and adequacy analysis of dysphagia diets at a regional hospital]

The study aims at confirming the adequacy of diets prescribed for dysphagia during hospitalization through a specific questionnaire to identify, give advice, and manage dysphagia. To compare and analyze the diet for dysphagia offered at our Hospital with the recommendations for a dysphagia diet published in recent nutritional literature. From the results obtained, to establish diet improvements (if necessary) and nursing working tools aimed at early detection of swallowing problems and decreasing the risk for Hyponutrition, dehydration and aspiration.

SUBJECTS AND METHODS

A cross-sectional study among patients from our hospital with a prescription for a dysphagia diet is performed, assessing the diet usefulness, the characteristics of the 30 patients admitted at the Hospital Complex of Segovia, in several nursing units and with an established diet for dysphagia for two months and with different pathologies. Ages were comprised between 68-85 years.

RESULTS

The questionnaire was analyzed and we verified that all patients had a swallowing impairment. The nutritional analysis showed an inadequate adaptation of hospital diet to dysphagia patients with regards to consistency of some dishes and the poor energy intake was significant (x 1339 kcal), poor protein intake (58 g), and a deficiency in some minerals (iron and calcium), and vitamins (vitamin C).

CONCLUSIONS

Dysphagia is a problem that affects a considerable number of patients in our Hospital (10-15%). The diet provided by the Hospital was inadequate before the study. A more adequate diet has been designed with regards to nutritional value and consistency, its indication is broaden, as well as interventional measures and previous patient assessment. The Nutrition Unit has implemented improvements in nutritional content.

Biweekly regimen of cisplatin, gemcitabine and vinorelbine for advanced non-small-cell lung cancer

PURPOSE

Improving chemotherapeutic efficacy in non-small cell lung cancer (NSCLC) will require the development of new strategies to better use currently available agents. To assess the efficacy and safety of a biweekly regimen of cisplatin, gemcitabine and vinorelbine for advanced non-small-cell lung cancer.

METHODS

Patients with selected stage IIIb (pleural effusion)/stage IV NSCLC, performance status of 0-2 and normal organ function were eligible. Treatment consisted of cisplatin 100 mg/m(2) on day 1 plus gemcitabine, 1,000 mg/m(2) and vinorelbine 25 mg/m(2) on days 1 and 15 every 28 days.

RESULTS

Of the 40 patients enrolled and assessable for response, there were five (12.5%) with confirmed complete response and 14 (35%) with a confirmed partial response for an overall response rate of 47.5%. Nine patients had stable disease while 12 (30%) progressed. Median progression-free survival and overall survival for all patients were 6.3 and 11.1 months, respectively. Toxicity was principally hematologic, with grade 3-4 neutropenia in 30%, and grade 3-4 nausea/vomiting in 22.5%. There were no treatment-related deaths.

CONCLUSIONS

The biweekly regimen of cisplatin, gemcitabine and vinorelbine is associated with a high rate of response, lesser toxicity than other three-drug regimens and no benefit of survival. Therefore, the regimen under study may be an appealing alternative when considering other treatment modalities for advanced lung cancer, such as neoadjuvant therapy.

Chronic ethanol intake modifies renin-angiotensin system-regulating aminopeptidase activities in mouse cerebellum

In developing cerebellum, where critical periods of vulnerability have been established for several basic substances, it has been extensively studied the wide array of abnormalities induced by exposure to ethanol (EtOH). However, little is known about the effects of EtOH consumption on cerebellar functions in adult individuals. Several studies show participation in cognitive activities to be concentrated in the lateral cerebellum (hemispheres), whereas basic motor functions such as balance and coordination are represented in the medial parts of the cerebellum (vermis and paravermis). In addition to the circulating renin angiotensin system (RAS), a local system has been postulated in brain. The effector peptides of the RAS are formed via the activity of several aminopeptidases (AP). The present work analyses the effect of chronic EtOH intake on the RAS-regulating AP activities in the soluble and membrane-bound fractions of two cerebellar locations: the hemispheres and the vermis. We hypothesize that cerebellar RAS is involved in basic motor functions rather than in cognitive activities.

Pyrrolidon carboxypeptidase activities in the hypothalamus-pituitary-thyroid and hypothalamus-pituitary-ovary axes of rats with mammary gland cancer induced by N-methyl nitrosourea

Pyrrolidon carboxypeptidase is an omega-peptidase that hydrolyses N-terminal pyroglutamyl residues from biologically active peptides such as gonadotropin-releasing and thyrotrophin-releasing hormones. We previously described a decrease in both rat and human pyrrolidon carboxypeptidase activity with breast cancer, suggesting that gonadotropin-releasing hormone may be an important local intracrine, autocrine and/or paracrine hormonal factor in the pathogenesis of breast cancer while playing a role in the tumoral process. However, the other susceptible substrate of pyrrolidon carboxypeptidase, thyrotrophin-releasing hormone, may also be modified with breast cancer, supporting an association between breast cancer and thyroid disorders. The present work analyses soluble and membrane-bound pyrrolidon carboxypeptidase activities in the hypothalamus-pituitary-thyroid and hypothalamus-pituitary-ovary axes in N-methyl nitrosourea-induced breast cancer in rats. Our aim was to determine the possible relationship between gonadotropin-releasing hormone and thyrotrophin-releasing hormone regulation through pyrrolidon carboxypeptidase activity. We propose that pyrrolidon carboxypeptidase activity dysregulation at various local and systemic levels may participate in the initiation, promotion and progression of breast cancer induced in rat by N-methyl nitrosourea through the increase in gonadotropin-releasing hormone. Since pyrrolidon carboxypeptidase activity also acts on thyrotrophin-releasing hormone, the dysregulation of this enzyme's activity could indirectly affect hypothalamus-pituitary-thyroid axis function, and thus potentially represent a link between the diseases of thyroid and breast cancer.

Serum oxytocinase activity is related to tumor growth parameters in N-methyl nitrosourea induced rat breast cancer

Oxytocinase has been reported to hydrolyse the peptide hormone oxytocin (OT). We have previously described changes in oxytocinase activity in human breast cancer, where a highly significant increase occurred in tumoral tissue. In the present work, we analysed oxytocinase activity in serum of rats with breast cancer induced by N-methyl-nitrosourea (NMU). We also correlated these data with the number and size of tumors and the body weight of the animals to evaluate the putative value of this activity as a biological marker of the disease. Our results confirm the involvement of OT in carcinogenesis and suggest a mayor role for oxytocinase activity in the development of breast cancer.

Serum pyrrolidone carboxypeptidase activity in N-methyl-nitrosourea induced rat breast cancer

Pyrrolidone carboxypeptidase (Pcp) (E.C. 3.4.19.3) is an omega peptidase widely distributed in animal fluids and tissues and hydrolyses N-terminal pyroglutamic residues from biologically active peptides such as gonadotropin releasing hormone (GnRH). Previous results obtained by us showed a decrease in human breast cancer Pcp activity, suggesting that this enzyme activity or its putative substrates may play a major role in breast cancer pathogenesis. The aim of the present work is to analyse serum Pcp activity in N-methyl-nitrosourea (NMU) induced rat mammary tumours using pyroglutamyl-beta-naphthylamide as substrate. Serum Pcp activity was significantly lower in NMU-treated rats than in controls. Moreover, multiple regression analysis showed a significant correlation between Pcp activity and the number and size of tumours and the body weight of the animals. Since NMU-induced carcinomas are mainly oestrogen-dependent, the decrease observed in Pcp activity may reflect an increase in circulating levels of GnRH that lead to an increase in gonadal steroid hormones production responsible, at least in part, for the initiation and promotion of the disease.

Clinical pharmacokinetics of statins

This article reviews the pharmacokinetic properties of HMG-CoA reductase inhibitors (or statins), as reported in humans. Most data presented here refer to commercially available statins (atorvastatin, fluvastatin, lovastatin and simvastatin), although statins that have recently been withdrawn (cerivastatin) or are currently under development (glenvastatin, pitavastatin and rosuvastatin) will also be considered. All statins with the exception of pitavastatin show very low systemic bioavailability due to an extensive first pass effect at the intestinal and/or hepatic level. Such a characteristic can be advantageous, since the liver is the target organ for statins. Unlike most statins, lovastatin and simvastatin are administered as inactive lactone prodrugs. Statins differ mainly in the degree of metabolism and the number of active and inactive metabolites. All statins but pravastatin show highly active metabolites, the pharmacological activity depending on the kinetic profile of both parent compound and active metabolites. Pravastatin has the lowest protein binding (50% vs. > 90%) and is eliminated by both metabolism and renal excretion. Atorvastatin shows the longest terminal half-life (11-14 h vs. 1-3 h). Pharmacokinetic interactions with statins are very likely to occur, particularly for those statins that are CYP3A4 substrates. However, although of extreme interest in clinical practice, this subject was extensively reviewed in a previous article and therefore is not discussed here.

Optimization of making barrel-fermented dry muscatel wines

The optimization of making barrel-fermented muscatel wines requires determining what type of must clarification is most suitable for the quality of the wine, as well as what type of barrel will yield the most acceptable wines. This is achieved by adding pectolytic enzymes to clarify part of the muscatel must statically; the rest is clarified by vacuum filtration. The musts obtained are fermented in French and American oak barrels and, once fermentation has ceased, they are kept with their lees for 2 months, with periodic stirring. Eleven conventional parameters and 31 volatile compounds were quantified, and a sensory analysis of the wines was produced, which led us to conclude that static clarification with pectolytic enzymes from the muscatel musts produces the best-structured wines and the larger content of higher alcohols, esters, and terpenic compounds. The wines fermented in American oak barrels received the highest overall marks, which may be due to the greater aromatic complexity given off by the compounds in the wood.

Effects of exogenous fatty acids and cholesterol on aminopeptidase activities in rat astroglia

Several studies have addressed the interaction between fatty acids and lipids with central nervous system peptides. Because aminopeptidases (AP) are involved in the regulation of neuropeptides, this work studies several AP expressed in cultured astroglia, after exogenous addition of oleic and linoleic fatty acids and cholesterol to the culture medium. Alanyl-AP, arginyl-AP, cystyl-AP, leucyl-AP, tyrosyl-AP and pyroglutamyl-AP activities were analysed in whole cells using the corresponding aminoacyl-beta-naphthylamides as substrates. Oleic acid inhibits alanyl-AP, cystyl-AP and leucyl-AP activities, whereas linoleic acid inhibits alanyl-AP, arginyl-AP and tyrosyl-AP activities. Neither oleic acid nor linoleic acid modifies pyroglutamyl-AP activity. In contrast, cholesterol increases arginyl-AP, cystyl-AP, leucyl-AP, tyrosyl-AP and pyroglutamyl-AP activities, although it does not modify alanyl-AP activity. The changes reported here suggest that oleic and linoleic fatty acids and cholesterol can modulate peptide activities via their degradation route involving aminopeptidases; each of them being differentially regulated.

Preclinical pharmacokinetics of statins

This review summarizes the pharmacokinetic properties of HMG-CoA reductase inhibitors (or statins) reported in animals. Lovastatin and simvastatin are administered as lactone prodrugs in contrast to other statins, which are generally formulated in the pharmacological active hydroxy acid form. Pharmacokinetics vary with the statin and animal species considered. Oral absorption is rapid and the bioavailability low due to an extensive first-pass metabolism. Pitavastatin is the exception, with high bioavailability in all species except monkeys (80% vs. 18%). Plasma protein binding is high for all statins (> 95%) except pravastatin (60%). Regardless of the dosing schedule (single or multiple), animal species and statin, the highest tissue levels are found in the liver--the target organ. Elimination is rapid with metabolism being the main elimination route for all statins, except for pitavastatin, which is only slightly metabolized, and pravastatin, which aside from metabolism is also eliminated by renal excretion. Statins undergo enterohepatic circulation and are recovered mainly in feces via bile, the extent of which is species-dependent. Metabolism varies with the statin and animal species, particularly the beta-oxidation of the dihydroxy heptanoic side chain that occurs primarily in rodents.

Effects of dietary cholesterol on pyroglutamyl aminopeptidase activity in mouse frontal cortex, pituitary, and adrenal glands

Pyroglutamyl aminopeptidase (pGluAP) is an omega peptidase that hydrolyzes biologically active peptides, such as thyrotropin-releasing hormone (TRH), with neuronal and extraendocrine functions. We analyzed the effects of a cholesterol-enriched diet on soluble and membrane-bound pGluAP activity in frontal cortex, pituitary and adrenal glands of male and female mice using fluorimetric assays. Significant increases were observed in soluble pGluAP activity in the frontal cortex and adrenal glands in males and in the pituitary in females. Membrane-bound pGluAP activity was increased in the frontal cortex and pituitary of males and females after the mice were fed a cholesterol-enriched diet. These increases may produce changes in the metabolism of endogenous substrates, including TRH, which may be related to alterations in its neuromodulator functions and to the possible relationship between TRH and other neurotransmitter systems.

Screening for adenylosuccinate lyase deficiency: clinical, biochemical and molecular findings in four patients

Adenylosuccinate lyase deficiency is an autosomal recessive defect of purine metabolism. Succinyladenosine (S-Ado) and succinylaminoimidazole carboxamide riboside (SAICAr) are the disease marker metabolites in physiological fluids. The Bratton-Marshall test for detection of SAICAr in urine has been added to the selective screening for inborn errors of metabolism that is carried out in our lab. During the last three years, around 2,000 patients have been screened by this method, resulting in the detection of four new cases with this disease. They all presented with severe psychomotor delay, hypotonia and refractory epilepsy since the neonatal period. The S-Ado/SAICAr ratio in cerebrospinal fluid was below 2, indicating that they correspond to the most severe form of the disease. New missense mutations were found in a heterozygous fashion in three patients. The study of purines in all patients with neurological disease of unknown etiology is highly recommended.

Differential effects of dietary cholesterol on aminopeptidase A, B and M in the frontal cortex of male and female mice

Although hypercholesterolemia and hypertension have been extensively associated, the regulatory mechanism underlying this relationship is poorly understood. Systemic and local renin-angiotensin systems are involved in the control of blood-pressure. Angiotensin II has been considered as the main effector peptide of renin-angiotensin system. However, other peptides derived from the metabolism of angiotensin II, as angiotensins III and IV have been shown to play significant roles. The aim of this study is to analyse the effect of dietary cholesterol on the activity of the enzymes involved in the metabolism of angiotensins II and III. Soluble and membrane-bound aminopeptidase A (aspartyl- and glutamyl-aminopeptidases), B (arginyl-aminopeptidase) and M (alanyl-aminopeptidase) activities were measured in the frontal cortex of male and female mice fed a cholesterol enriched-diet (1% cholesterol; 0.5 cholic acid). Soluble and membrane-bound aminopeptidases B and M did not change in male or female cholesterol groups. Significant increases were observed in membrane-bound aspartyl- and glutamyl-aminopeptidase activities in both cholesterol groups. Soluble aspartyl- and glutamylaminopeptidases did not change in male cholesterol group, but significant decreases were detected in female cholesterol group. Our results may indicate that the metabolism of angiotensin II to angiotensin III by aminopeptidase A is increased, but angiotensin III metabolism by aminopeptidases B and M is not modified after cholesterol intake; so cholesterol may enhance the effects of angiotensin III, at least, at the cortical level.

Pituitary aminopeptidase activities involved in blood-pressure regulation are modified by dietary cholesterol: sex differences

Given that the existence of a local renin-angiotensin system (RAS) in the pituitary and its participation in the regulation of blood pressure and other biological functions are widely accepted, the aim of this work is to analyze the influence of dietary cholesterol on the activity of the enzymes involved in the metabolism of the effector peptides of the renin-angiotensin system (angiotensin II and III) and vasopressin, in the pituitary of male and female mice fed on a cholesterol-enriched diet (1% cholesterol and 0.5% cholic acid). Soluble and membrane-bound pituitary aminopeptidase A (aspartyl- and glutamyl-aminopeptidase), aminopeptidase M (alanyl-aminopeptidase), aminopeptidase B (arginyl-aminopeptidase) and cystinyl-aminopeptidase activities were fluorimetrically measured. In female mice, cholesterol-enriched diet produced a significant increase in soluble aspartyl- and membrane-bound aspartyl- and glutamyl-aminopeptidase activities, and a significant decrease in membrane-bound alanyl-, arginyl- and cystinyl-aminopeptidase activities. In male mice, after feeding the diet, a significant increase in soluble glutamyl- and membrane-bound arginyl-aminopeptidase activities was observed. Our results indicate differential effects of dietary cholesterol on the metabolism of angiotensin II and III and vasopressin in the pituitary of male and female mice.

Pharmacokinetic interactions of statins

Statins have shown high efficacy in managing hypercholesterolemia in patients requiring chronic drug treatment, particularly those who show comorbidity and thus receive concomitant medication for other pathologies. According to the reported data extensively reviewed in this work, absorption and elimination are the kinetic processes mainly affected by this type of interaction, while distribution and protein binding is only slightly modified. Products (drugs or food) with the ability to affect the activity of protein-mediated transport and/or P450 cytochrome systems, particularly the P-glycoprotein and/or CYP3A4, respectively, are expected to cause pharmacokinetic interactions with statins. The intensity of the interaction is dependent on the statin kinetic profile and the capacity of the coadministered product to alter the systems mentioned above. Modification of the total HMG-CoA inhibitors instead of just the parent drug profile is to be considered when evaluating the clinical relevance of the interaction. Interindividual variability must also be taken into account when extrapolating results from studies performed in small groups of relatively healthy individuals. Patients treated with other drugs that have the potential ability to interact with statins should be monitored.

Acetylcholinesterase inhibitor SDZ ENA 713 (Rivastigmine) increases brain pyrrolidone carboxyl peptidase activity

Pyroglutamyl-ended forms of amyloid-beta-peptide are present in senile plaques in some individuals with Alzheimer type dementia. Single oral administration of the acetylcholinesterase inhibitor SDZ ENA 713 (rivastigmine (+)-(S)-N-ethyl-3-[(1-dimethylamino)ethyl]-N-methylphenylcarbamate hydrogen tartrate) increases basal and K(+)-stimulated pyrrolidone carboxyl peptidase (Pcp) activity in mice frontal cortex synaptosomes in a dose-dependent manner. These results suggest that this drug may ameliorate ATD cognitive deficits acting not only facilitating cholinergic transmission but also avoiding the formation of pyroglutamyl-ended amyloid-beta-peptides (A beta pE) deposition through the activation of Pcp.

[Influence of estradiol on pyroglutamyl aminopeptidase activity in the frontal cortex of ovariectomized mice]

INTRODUCTION

Pyroglutamyl aminopeptidase (pGluAP) is an omega peptidase widely distributed in fluid and tissues which hydrolyses biological active peptides including thyrotropin releasing hormone (TRH). OBJECTIVES. The aim of present work is to study the influence of estradiol on soluble and membrane bound pGluAP activity in the frontal cortex of female mice.

MATERIAL AND METHODS

Soluble and membrane bound pGluAP activities in frontal cortex of ovariectomized mice and ovariectomized mice injected with different doses of estradiol were measured using espectrophotometric assays.

RESULTS

Soluble pGluAP activity in frontal cortex did not change after ovariectomy or after the administration of the different doses of estradiol. However, membrane bound pGluAP activity showed a significant increase after ovariectomy. After the administration of the lower dose of estradiol, membrane bond pGluAP activity returned to the same levels detected before the ovariectomy.

CONCLUSION

Estradiol modifies membrane bound pGluAP activity which is the principal enzyme involved in the hydrolysis of TRH. Therefore, misregulation of estradiol levels may produce modifications in the neuromodulatory functions of TRH.

Population kinetics of tobramycin in neonates

The population kinetics of tobramycin were studied in 140 neonates (100/40 patients for the index/validation groups, respectively) of 30 to 42 weeks' gestational age and 0.8 to 4.25 kg current body weight in their first 2 weeks of life, undergoing routine therapeutic drug monitoring of their tobramycin serum levels. The 365 tobramycin concentration measurements obtained were analyzed by use of NONMEM according to a one-compartment open model with zero-order absorption and first-order elimination. The effect of a variety of demographic, developmental, and clinical factors (gender, height, birth weight, current weight, gestational age, postnatal age, postconceptional age, and serum creatinine concentration) on clearance and volume of distribution was investigated. Forward selection and backward elimination regression identified significant covariates. The final pharmacostatistical model with influential covariates was as follows (full population): clearance (L/h) = 0.0508 x current weight (kg), multiplied by 0.843 if birth weight was 2.5 kg or less (low-birthweight infants), and volume of distribution (L) = 0.533 x current weight (kg). Using the proportional error model for the random-effects parameters, interindividual variability for clearance and for volume of distribution was determined to be 25.8% and 21.9%, respectively, and the residual variability was 19.2%. In this study, the use of the NONMEM gave significant and consistent information on the pharmacokinetics and the determinants of the pharmacokinetic variability of tobramycin in neonates when compared with available bibliographic information. Moreover, the final population pharmacokinetic model may be used to design a priori recommendations for tobramycin and to improve the dosing readjustments through Bayesian estimation.

Geochemical evolution of amino acids in dentine of Pleistocene bears

A linear correlation was established between aspartic acid racemization ratio from cave bear dentine collagen and absolute dating. The high correlation coefficient obtained allowed age calculation through amino acid racemization. Aspartic acid and glutamic acid racemization kinetics have also been explored in dentine from a North American black bear (Ursus americanus Pallas). Three sample sets were prepared for kinetic heating experiments in nitrogen atmosphere: one water soaked, one with a water-saturated nitrogen atmosphere, and one without any moisture. It was possible to show that the presence of water is a factor controlling amino acid racemization rate. The aspartic acid in a heating experiment at 105 degrees C shows an "apparent kinetics reversal" which can be explained by a progressive hydrolysis of amino acid chains (proteins and polypeptides). Because of the low potential of collagen preservation over long periods of time, the apparent kinetics reversal phenomenon will not affect the dating of old material where no traces of collagen remain. An apparent kinetics reversal was not observed in glutamic acid, which racemizates more slowly.

[Bilateral hypodensity of the basal ganglia. Clinico-evolutionary correlation in children]

INTRODUCTION

The presence in neuroimaging of areas of symmetrical bilateral hypodensity in the basal ganglia (SBHBG) is a striking and unusual finding.

OBJECTIVE

To determine the aetiology, clinical significance and evolution of a group of paediatric patients with SBHBG.

PATIENTS AND METHODS

We made a study of 21 patients with neuroimaging studies (CT or MR) showing SBHBG. The affected area was related to the aetiology, clinical features and evolution.

RESULTS

The ages varied between 4 months and 16 years. In 7 cases Leigh s disease was diagnosed, 5 had had acute hypoxia, 4 type I glutaric aciduria, and 1 case each of methylmalonic aciduria, Ia gluconeogenesis, CO intoxication, acute striatal necrosis and bacterial meningitis. The putamen was affected in 6 cases, globus pallidus in 4 cases and the lenticular nucleus was damaged in the rest. Three cases also had lesions in the caudate nucleus. MR was better than CT for localization of the precise area involved. Clinically, 13 cases had extrapyramidal signs. We found no relation between the size, localization of the lesion and the prognosis, which was more dependent on the aetiology, only one patient (CO intoxication) recovered and eight died (Leigh s disease and 1 case of hypoxia).

CONCLUSIONS

The presence of SBHBG in a patient makes extensive study necessary to find the aetiology. It is a nonspecific finding, usually of metabolic origin and with little correlation with the clinical condition. Its presence implies a poor prognosis and raises suspicion of the presence of certain neurological disorders.

[Influence of alcohol on brain aminopeptidases. An in vitro study]

INTRODUCTION

It is well known the depressor effect of alcohol on several inhibitory nervous centres. This can be due to the inhibition that induces in the release of different type of neurotransmitters, and because alcohol can increase the membrane fluidity and changes the function of proteins inserted in the membrane. Several aminopeptidases (AP) have been described as enzymes that regulate the activity of peptide neurotransmitters. In the present work, the influence of alcohol (25, 50 and 100 mM) on several aminopeptidase activities (alanyl AP, arginyl AP, cystinyl AP, leucyl AP and tyrosyl AP) has been determined in synaptosomes obtained from the cortex of mouse, under basal and K+ stimulated conditions and their calcium dependence, in a non toxic in vitro model.

MATERIAL AND METHODS

AP activities were determined using aminoacyl ? naphthylamides as substrates. Non toxic in vitro model were demonstrated analyzing free radical generation, lipid peroxidation and oxidation of synaptosomal proteins. In addition, the bioenergetic behavior of synaptosomes was determined under different experimental protocols.

RESULTS

In basal conditions, alcohol produces a dose related inhibition of alanyl AP activity. The rest of activities show a biphasic behavior. In this way, depending on the concentration of alcohol used, aminopeptidases are inhibited or stimulated. Depolarization with K+ 25 mM leads to a decrease of alanyl AP and tyrosyl AP activities but does not change the rest of activities. The presence of alcohol under stimulated conditions produces the inhibition of all the enzymatic activities, specially with the highest concentrations used.

CONCLUSIONS

Alcohol modifies several aminopeptidase activities from synaptosomes of the cortex of mouse, acting in different ways under basal or stimulated conditions. These effects seem not to be related with degenerative events induced by alcohol. Therefore, a specific effect of this substance on the neurotransmisory/neuromodulatory systems mediated by neuropeptides must exist, modifying the enzymes that are responsible of their degradation.

IgH, TCR-gamma, and TCR-beta gene rearrangement in 80 B- and T-cell non-Hodgkin's lymphomas: study of the association between proliferation and the so-called "aberrant" patterns

The current study analyzes the rearrangement pattern of immunoglobulin H (IgH), T-cell receptor (TCR)-gamma, and TCR-beta genes in a group of 80 non-Hodgkin's lymphomas (NHL) of different histologic subtypes (43 B-cell and 37 T-cell types). The sensitivity and specificity provided by polymerase chain reaction amplification of these loci are evaluated. The association between the proliferation index and the presence of the so-called "aberrant" or "dual" rearrangements is also considered. Ninety-one percent of B-cell NHL showed IgH gene monoclonality, and 21% also exhibited a monoclonal pattern in one of the TCR genes. Among T-cell NHL, the sensitivity of the study was 65% for the TCR-gamma gene and 46% for the TCR-beta gene. The total sensitivity was 76%, amplifying both loci. IgH gene aberrant rearrangements were observed in 16% of T-cell neoplasms. A substantial percentage of dual rearrangements were detected in precursor and mature B- and T-cell NHL. B-cell NHL showed a tendency toward higher values of proliferation when aberrant rearrangements were present; however, this trend was not significant. Furthermore, in the case of T-cell NHL there was a significant negative association between these two variables.

[Dietary cholesterol modifies pyroglutamyl aminopeptidase activity in mouse frontal cortex. Sexual differences]

INTRODUCTION

Pyroglutamyl aminopeptidase (pGluAP) is an omega peptidase widely distributed in fluid and tissues, which hydrolyses biological active peptides including thyrotropin-releasing-hormone (TRH). In the last years, different endocrine and extraendocrine functions have been attributed to TRH.

OBJECTIVES

The aim of present work is to study the influence of high dietary cholesterol on soluble and membrane bound pGluAP activity in frontal cortex of male and female mice. Material and methods. Soluble and membrane bound pGluAP activities of frontal cortex of mice feeding during 15 days, a standard diet enriched with cholesterol (1%) and cholic acid (0.5%) were measured using fluorimetric assays.

RESULTS

Significant increases were observed in membrane bound pGluAP activity in males and females. No changes were detected in soluble pGluAP activity in frontal cortex of females but a significant increase was observed in this enzymatic activity in males.

CONCLUSIONS

High dietary cholesterol induces a significant increase in tissue pGluAP activity. These increases may produce changes in TRH metabolism which may be related with alterations in its neuromodulatory functions and with the possible relationship between TRH and other neurotransmitter systems.