Contrasting magma chemistry in the Candelaria IOCG district caused by changing tectonic regimes

Iron oxide-copper-gold (IOCG) deposits are a vital source of copper and critical elements for emerging clean technologies. Andean-type IOCG deposits form in continental arcs undergoing extension, and they have a temporal relationship with magmatism although they do not exhibit a close spatial relation with the causative intrusions. The processes required to form IOCG deposits and their potential connections to iron oxide-apatite (IOA)-type mineralization remain poorly constrained, as well as the characteristics of magmatism linked to both deposit types. Here we combine zircon U-Pb geochronology with zircon trace element geochemistry of intrusive rocks associated with the Candelaria deposit, one of the world's largest IOCG deposits, to unravel distinctive signatures diagnostic of magmatic fertility. Our results reveal a marked transition in the geochemistry of intrusions in the Candelaria district, characterized by changes in the redox state, water content and temperature of magmas over time. The oldest magmatic stage (~ 128-125 Ma), prior to the formation of the Candelaria deposit, was characterized by zircon Eu/Eu* ratios of 0.20-0.42, and redox conditions of ΔFMQ - 0.4 to + 1.0. The earliest magmatic stage related to the formation of Fe-rich mineralization at Candelaria (118-115 Ma) exhibits low zircon Eu/Eu* ratios (0.09-0.18), low oxygen fugacity values (ΔFMQ ~- 1.8 to + 0.2) and relatively high crystallization temperatures. In contrast, the youngest stage at ~ 111-108 Ma shows higher zircon Eu/Eu* (~ 0.37-0.69), higher oxygen fugacity values (ΔFMQ ~  + 0.4 to + 1.3) and a decrease in crystallization temperatures, conditions that are favorable for the transport and precipitation of sulfur and chalcophile elements. We conclude that Candelaria was formed through two distinct ore-forming stages: the first associated with a reduced, high temperature, water-poor magma developed under a low tectonic stress, followed by a more oxidized, water-rich, and low temperature magmatic event related to a compressional regime. The first event led to Fe-rich and S-poor IOA-type mineralization, while the second event with geochemical signatures similar to those of porphyry copper systems, generated the Cu- and S-rich mineralization. This late stage overprinted preexisting IOA mineralization resulting in the formation of the giant Candelaria IOCG deposit.

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.

Effectiveness of a specific follow up program for the management of the mental components of post-intensive care syndrome and chronic pain after COVID-19: results from the PAIN-COVID randomized clinical trial

BACKGROUND

Critical COVID-19 survivors are at risk of developing Post-intensive Care Syndrome (PICS) and Chronic ICU-Related Pain (CIRP). We determined whether a specific care program improves the quality of life (QoL) of patients at risk of developing PICS and CIRP after COVID-19.

METHODS

The PAIN-COVID trial was a parallel-group, single-centre, single-blinded, randomized controlled trial. The intervention consisted of a follow up program, patient education on PICS and pain, and a psychological intervention based on Rehm's self-control model in patients with abnormal depression scores (≥8) in the Hospital Anxiety and Depression Scale (HADS) at the baseline visit. QoL was evaluated with the 5-level EQ 5D (EQ 5D 5 L), mood disorders with the HADS, post-traumatic stress disorder (PTSD) with the PCL-5 checklist, and pain with the Brief Pain Inventory short form, the Douleur Neuropathique 4 questionnaire, and the Pain Catastrophizing Scale. The primary outcome was to determine if the program was superior to standard-of-care on the EQ visual analogue scale (VAS) at 6 months after the baseline visit. The secondary outcomes were EQ VAS at 3 months, and EQ index, CIRP incidence and characteristics, and anxiety, depression, and PTSD at 3 and 6 months after baseline visits.

CONCLUSIONS

This program was not superior to standard care in improving QoL in critical COVID-19 survivors as measured by the EQ VAS. However, our data can help establish better strategies for the study and management of PICS and CIRP in this population.

TRIAL REGISTRATION

# NCT04394169, registered on 5/19/2020.

Expert range maps of global mammal distributions harmonised to three taxonomic authorities

AIM

Comprehensive, global information on species' occurrences is an essential biodiversity variable and central to a range of applications in ecology, evolution, biogeography and conservation. Expert range maps often represent a species' only available distributional information and play an increasing role in conservation assessments and macroecology. We provide global range maps for the native ranges of all extant mammal species harmonised to the taxonomy of the Mammal Diversity Database (MDD) mobilised from two sources, the Handbook of the Mammals of the World (HMW) and the Illustrated Checklist of the Mammals of the World (CMW).

LOCATION

Global.

TAXON

All extant mammal species.

METHODS

Range maps were digitally interpreted, georeferenced, error-checked and subsequently taxonomically aligned between the HMW (6253 species), the CMW (6431 species) and the MDD taxonomies (6362 species).

RESULTS

Range maps can be evaluated and visualised in an online map browser at Map of Life (mol.org) and accessed for individual or batch download for non-commercial use.

MAIN CONCLUSION

Expert maps of species' global distributions are limited in their spatial detail and temporal specificity, but form a useful basis for broad-scale characterizations and model-based integration with other data. We provide georeferenced range maps for the native ranges of all extant mammal species as shapefiles, with species-level metadata and source information packaged together in geodatabase format. Across the three taxonomic sources our maps entail, there are 1784 taxonomic name differences compared to the maps currently available on the IUCN Red List website. The expert maps provided here are harmonised to the MDD taxonomic authority and linked to a community of online tools that will enable transparent future updates and version control.

A reappraisal of the species richness of Euneomys Coues 1874 (Rodentia, Cricetidae), with emendations of the type localities of Reithrodon fossor Thomas 1899 and Euneomys mordax Thomas 1912

The genus Euneomys is mostly distributed in the open environments of the central and southern Andes, adjacent Patagonian steppes of Argentina and Chile, and in several islands of the Tierra del Fuego Archipelago. This genus includes three living species: E. chinchilloides, E. fossor, and E. mordax. Euneomys fossor is a poorly known species, with an uncertain geographic provenance and known from a single specimen, whose distinction from the other species of the genus has not been accurately assessed. Here, using qualitative and quantitative morphological evidence, plus published information about karyotypes and genetic variation, we evaluate the taxonomic status of E. fossor and E. noei, a nominal form usually considered a synonym of E. mordax. Based on multivariate analysis of cranial measurements and morphological discrete traits, we recognize two main morphotypes within Euneomys, one referable to E. chinchilloides (with dabbenei, petersoni, and ultimus as synonyms), and another including E. fossor, E. mordax, and E. noei. The recognition of two major groups within Euneomys is also supported by molecular and chromosomal data. By the principle of the priority, the names of E. chinchilloides and E. fossor applies for each one of these morphotypes. In addition, after discussing the pros and cons of replacing the name mordax by fossor, we emended the type localities of both forms.

Disseminated intravascular coagulation as a form of presentation of coronavirus-19 disease. Clinical case

The covid-19 disease (coronavirus disease 2019) is a novel disease causing a world pandemic. Its presentation varies from an asymptomatic infection to a pneumonia with acute respiratory distress syndrome. We present a case presenting initially as a covid-19 pneumonia together with a disseminated intravascular coagulopathy consisting of arterial and venous thrombosis in different locations and a shock requiring admission in the intensive care unit. The abnormal coagulation test in covid-19 patients have been described since the first cases observed in Wuhan, China, as well as an increased incidence of venous thrombosis. On the contrary, a higher incidence of arterial thrombosis has not been described in these patients. The unusual case we present could be a manifestation of this altered tests.

Open-source raspberry Pi-based operant box for translational behavioral testing in rodents

BACKGROUND

Rodents have been used for decades to probe neural circuits involved in behavior. Increasingly, attempts have been developed to standardize training paradigms across labs; and to use visual/auditory paradigms that can be also tested in humans. Commercially available systems are expensive and thus do not scale easily, and are not optimized for electrophysiology.

NEW METHOD

Using the rich open-source technology built around Raspberry Pi, we were able to develop an inexpensive (<$1000) visual-screen based operant chamber with electrophysiological and optogenetic compatibility. The chamber is operated within MATLAB/Simulink, a commonly used scientific programming language allowing for rapid customization.

RESULTS

Here, we describe and provide all relevant details needed to develop and produce these chambers, and show examples of behavior and electrophysiology data collected using these chambers. We also include all of the tools needed to allow readers to build and develop their own boxes (CAD models for 3D printing and laser-cutting; PCB-board design; all bill of materials for required parts and supplies, and some examples of Simulink models to operate the boxes).

COMPARISON WITH EXISTING METHODS

The new boxes are far more cost-effective than commercially available environments and allow for the combination of automated behavioral testing with electrophysiological read-outs with high temporal precision.

CONCLUSION

These open-source boxes can be used for labs interested in developing high-throughput visual/auditory behavioral assays for ∼ 10th the cost of commercial systems.

Six New Cases of a Caterpillar-Induced Bleeding Syndrome

We describe six new cases of a hemorrhagic diathesis induced by contact with Lonomia achelous caterpillars. Onset of clinical bleeding varied between a few hours and 10 days post-exposure. Laboratory coagulation tests showed prolonged PT, PTT and ThT; normal platelets and a marked decrease of fibrinogen, factor V, plasminogen and factor XIII (including its subunits A and S). Factors VII, II and alfa 2 anti-plasmin were variably affected. In addition, activation of the fibrinolytic system and the generation of a procoagulant effect could also be demonstrated. Two cases developed severe hemorrhagic diathesis and one of them died of a cerebral hemorrhage. Different aspects of this rare syndrome are discussed in relation to its complex physiopathology and the variability observed in all clinical and laboratory manifestations. Therapeutic recommendations and some possible hazards following replacement transfusions are also considered.

Karyotypic variation in the Andean rodent Phyllotisxanthopygus (Waterhouse, 1837) (Rodentia, Cricetidae, Sigmodontinae)

Phyllotisxanthopygus (Waterhouse, 1837) is an Andean rodent endemic to South America. Despite its wide geographical distribution in Argentina, few individuals have been studied on the cytogenetic level and only through conventional staining. In this work, chromosome characterization of Argentine samples of this species was performed using solid staining, C-banding and base-specific fluorochromes. Twenty two specimens were analyzed, collected in the provinces of Jujuy, Catamarca, and the north and south of Mendoza. All studied specimens showed 2n=38, having mostly the bi-armed autosomes, metacentric or submetacentric. Fundamental Number varied between 70 and 72. These changes were due to the presence of chromosome heteromorphisms in individuals from southern Mendoza and Jujuy. C-banding revealed pericentromeric blocks of constitutive heterochromatin in most chromosomes. Acrocentric chromosomes involved in heteromorphisms showed high variation in the amount of heterochromatin within and among populations. Additionally, banding with fluorochromes (DAPI and chromomycin A3) revealed homologous localization of AT and GC rich regions among chromosomes of the different populations analyzed. Comparisons among heteromorphic pairs suggested, however, that the variation might be the result of complex chromosome rearrangements, involving possibly amplifications and/or deletions of heterochromatic segments. These results are in accordance with molecular studies that indicate genetic variability within and among the populations of this taxon.

[Usefulness of a multidimensional self-administered questionnaire for the clinical management of a pain treatment unit]

OBJECTIVE

To study the feasibility of a multidimensional self-administered questionnaire before the patient is seen at the first visit in a clinical Pain Treatment Unit (PTU) of a tertiary hospital, and its impact on the management of patients in the first visit.

PATIENTS AND METHODS

Cross-sectional study. Self-administered questionnaire that gathered: socio-demographic data, medical history of pain, pain perception (intensity and characteristics), comorbidity of pain and patient expectations of analgesic treatment ("What do you expect from our treatment? If we cannot resolve your pain, what level of pain would you be willing to live with?). A descriptive analysis was performed.

RESULTS

A total of 293 consecutive patients (31% men, 69% women), mean age (SD) 62 (16) years-old, were included in 2011. All patients completed and returned the questionnaire before the first visit to the PTU. The questionnaire was completed fully and correctly by 80% (234, 95% CI: 75-84) of the patients, and the rest completed the questionnaire with some points unanswered. About 24% (70/293, 95% CI: 19-29) of the patients should not have been referred to the PTU [20% were not attended]. A small percentage (9%,26/293, 95% CI: 6-13) were evaluated as «urgent'» and visited over the following 7 days, with 19% (56/293, 95%CI: 15-24) being «preferential» (visited before 15 days) and 52% (152/293, 95% CI: 46-58) as «non-urgent/non-preferential» (visited before 60 days). Almost one third (30%, 87/293, 95% CI: 25-35) did not need a second visit to the PTU. Patient expectations: 21% expected complete pain relief and 64% would accept a lower pain intensity score of 4.

CONCLUSION

The use of a multidimensional self-administered questionnaire before the first visit to a clinical Pain Treatment Unit of a tertiary hospital was a practicable and useful tool for the management of patients on the first visit. Likewise, the questionnaire provided information on the patient's perception of pain and the expectations concerning the analgesic treatment.

XY1Y2 chromosome system in Salinomys delicatus (Rodentia, Cricetidae)

Salinomys delicatus is considered a rare species due to its restricted and patchy distribution, poor records and low abundances. It is also the phyllotine with the lowest known diploid chromosome number (2n = 18), however its sex chromosome system has never been described. Here, we studied the chromosomes of six females and three males with bands G, C, DAPI/CMA(3) and meiosis. In males, the chromosome number was 2n = 19, with one large metacentric X-chromosome and two medium-sized acrocentrics absent in females. The karyotype of females was the same as previously described (2n = 18, FN = 32), with X-chromosomes being metacentric and the largest elements of the complement. In males, the two acrocentrics and the large metacentric form a trivalent in meiotic prophase. This indicates that S. delicatus has XY(1)Y(2) sex chromosomes, which is confirmed by G and DAPI bands. Constitutive heterochromatin (CH) is restricted to small pericentromeric blocks in all chromosomes. The X-chromosome shows the largest block of centromeric CH, which could favor the establishment of this X-autosome translocation. This sex chromosome system is rare in mammals and, compared with other phyllotine rodents, S. delicatus seems to have undergone a major chromosome restructuring during its karyotypic evolution.

Selección de especies leñosas por vacunos en silvo- pastoreo de un bosque semicaducifolio en venezuela

Para determinar la selección de plantas leñosas por vacunos en silvopastoreo de un bosque semicaducifolio tropical (BSCT), se evaluaron fragmentos epidérmicos en muestras de heces de 14 vacunos machos Brahman x Holstein (390,4 ± 18,0 kg peso vivo). Los animales pastaron durante 91 días sobre 81 ha localizadas en el estado Portuguesa, Venezuela, donde 50 ha correspondieron a un BSCT y el resto a pastizales con predomino de Cynodon nlemfuensis, Sporobolus indicus, Cyperus sp. y Axonopus sp. Empleando la técnica de puntos en cuadrante sobre transectas, en el bosque se identificaron 22 especies de plantas leñosas, agrupadas en 11 familias botánicas con 40,9% de las especies dentro de la familia Fabaceae. La especie Guazuma ulmifolia tuvo la mayor dominancia relativa (60,4%), acumulando conjuntamente con Pithecellobium lanceolatum y Samanea saman el 81,1% de este parámetro. Estas mismas especies mostraron los mayores índices de valor de importancia (162,6; 24,8 y 26,5 respectivamente). Las Poaceae presentaron la mayor frecuencia relativa de aparición de fragmentos epidémicos en heces con el 49,6%, mientras el conjunto de plantas leñosas presentó un 46,2%, del cual las Fabaceae alcanzaron el 80,7%. Las especies más seleccionadas fueron Inga laurina, Machaerium humboldtianum, S. saman y Sida acuta, con un Índice de Ivlev medio de 0,60 ± 0,09. La composición química del follaje de las plantas leñosas sugiere un patrón de selección ajustado a la oferta de nutrientes de cada especie, resaltando el valor estratégico del BSCT en sistemas de silvopastoreo en ambientes tropicales.

Stroke in Young People: The Increasing Role of Advanced Imaging

Ischemic stroke in young people is an unexpected event due to a wider variety of causes compared to the older population. This study highlights the increasing role of neuroimaging in the diagnosis, prognosis and treatment of young stroke patients. Thirty young adult patients (age range, 15–45 years) with acute ischemic stroke diagnosis were retrospectively included and studied at our institution during 2009. The mean age of patients was 35 years and 50% were men. The stroke etiology was established in 86% of cases (n=26), 7% (n=2) were due to atherosclerosis of the main vessels, 10% (n=3) were related to cardioembolism, 27% (n=8) were due to arterial dissection and 43% (n=13) responded to miscellaneous etiologies. The cause remained unexplained in 14% (n=4) of cases. The aims of neuroimaging in the challenging study of young stroke patients are to confirm the ischemic nature of the lesion, to determine its location, and to verify the patency of major neck and intracranial arteries. Both MRI and MSCT offer the best sensitivity and spatial resolution.

[Impact of melanoma diagnosis on sun protection]

INTRODUCTION

Knowledge of the dangers of sun exposure does not always lead to changes in behavior. Failure to make behavioral adjustments is of particular concern in high-risk patients.

OBJECTIVES

a) To assess the impact of melanoma diagnosis on knowledge, attitudes, and behaviors relating to sun protection, and b) to identify factors that could influence sun protection behaviors.

METHODS

A coded, anonymous questionnaire was given to 195 patients with a recent diagnosis of melanoma. Data were collected on clinical and demographic variables and on knowledge, attitudes, and behaviors relating to sun protection before and after diagnosis. The questionnaire also addressed patients' sense of distress and guilt following diagnosis.

RESULTS

Sun protection behaviors improved following diagnosis in 66% of patients. Although 98% of patients reported having received advice on sun protection following diagnosis, 15% continued to take inadequate sun protection measures. The probability of behavioral improvement following diagnosis was 4 times greater in women than in men. The subgroup of patients whose behavior improved had worse behaviors prior to diagnosis than did those who showed no improvement. Patients who expressed distress and feelings of guilt following diagnosis were more likely to improve their sun protection behavior. Age, tumor site, intensiveness of treatment, and belief that a suntan is healthy had no significant influence on behavioral change.

CONCLUSIONS

Melanoma diagnosis is associated with increased knowledge of sun protection measures and improvement in behaviors. Nevertheless, patients continue to use inadequate sun protection measures. Identification of barriers to optimal sun protection behavior may be instrumental in designing targeted educational campaigns.

Nucleotide variability of the porcine SERPINA6 gene and the origin of a putative causal mutation associated with meat quality

The serpin peptidase inhibitor, clade A, member 6 gene (SERPINA6), also known as corticosteroid-binding globulin or CBG, is involved in obesity and stress sensitivity. Previous studies have reported putative causal mutations within that gene in the porcine species. To characterize a hypothetical selective footprint, we have resequenced approximately 6 kb of coding and non-coding fragments in 20 pigs comprising domestic breeds and wild boars from Asia and Europe. Nucleotide variability was found to be far greater within Asian pig breeds than European breeds (π = 1% vs. 0.05%, respectively), which is consistent with pig evolutionary history. The putative causal amino acid substitution p.Gly307Arg (SNP c.919G>A) associated with meat quality (drip loss) was only detected in European domestic pig breeds, suggesting a very recent mutation that appeared after domestication in Europe. No support for positive selection was detected, as no reduction in levels of diversity surrounding the mutation was found in lean breeds with respect to wild boar.

[Using the CTrach Laryngeal Mask Airway in the awake patient with an expected difficult airway]

The method of choice for managing the expected difficult airway is tracheal intubation with an awake patient breathing spontaneously. The CTrach Laryngeal Mask Airway (LMA) is a modified version of the Fastrach LMA that incorporates a fiberoptic system that provides a view of the glottis during ventilation and intubation. We describe 2 cases of intubation in which the CTrach device was used in patients breathing spontaneously. In both cases difficult intubation was foreseen. The CTrach LMA facilitates management of the airway in these circumstances. It is well tolerated and enables a clear view of the airway and permits assisted ventilation when necessary.

Source analysis of alpha rhythm reactivity using LORETA imaging with 64-channel EEG and individual MRI

Conventional EEG and quantitative EEG visual stimuli (close-open eyes) reactivity analysis have shown their usefulness in clinical practice; however studies at the level of EEG generators are limited. The focus of the study was visual reactivity of cortical resources in healthy subjects and in a stroke patient. The 64 channel EEG and T1 magnetic resonance imaging (MRI) studies were obtained from 32 healthy subjects and a middle cerebral artery stroke patient. Low Resolution Electromagnetic Tomography (LORETA) was used to estimate EEG sources for both close eyes (CE) vs. open eyes (OE) conditions using individual MRI. The t-test was performed between source spectra of the two conditions. Thresholds for statistically significant t values were estimated by the local false discovery rate (lfdr) method. The Z transform was used to quantify the differences in cortical reactivity between the patient and healthy subjects. Closed-open eyes alpha reactivity sources were found mainly in posterior regions (occipito-parietal zones), extended in some cases to anterior and thalamic regions. Significant cortical reactivity sources were found in frequencies different from alpha (lower t-values). Significant changes at EEG reactivity sources were evident in the damaged brain hemisphere. Reactivity changes were also found in the "healthy" hemisphere when compared with the normal population. In conclusion, our study of brain sources of EEG alpha reactivity provides information that is not evident in the usual topographic analysis.

Integrating Y-chromosome, mitochondrial, and autosomal data to analyze the origin of pig breeds

We have investigated the origin of swine breeds through the joint analysis of mitochondrial, microsatellite, and Y-chromosome polymorphisms in a sample of pigs and wild boars with a worldwide distribution. Genetic differentiation between pigs and wild boars was remarkably weak, likely as a consequence of a sustained gene flow between both populations. The analysis of nuclear markers evidenced the existence of a close genetic relationship between Near Eastern and European wild boars making it difficult to infer their relative contributions to the gene pool of modern European breeds. Moreover, we have shown that European and Far Eastern pig populations have contributed maternal and paternal lineages to the foundation of African and South American breeds. Although West African pigs from Nigeria and Benin exclusively harbored European alleles, Far Eastern and European genetic signatures of similar intensity were detected in swine breeds from Eastern Africa. This region seems to have been a major point of entry of livestock species in the African continent as a result of the Indian Ocean trade. Finally, South American creole breeds had essentially a European ancestry although Asian Y-chromosome and mitochondrial haplotypes were found in a few Nicaraguan pigs. The existence of Spanish and Portuguese commercial routes linking Asia with America might have favored the introduction of Far Eastern breeds into this continent.

Longitudinal analysis of cytokine gene expression and parasite load in PBMC in Leishmania infantum experimentally infected dogs

Canine visceral leishmaniasis (CVL) is caused by Leishmania infantum, an intracellular protozoan parasite that causes a severe infectious disease. To evaluate the gene expression profile associated to CVL in vivo, we have measured monthly by real-time PCR over one year the IL-4, IL-10, IL-12, IL-13, IFN-gamma, TGF-beta and TNF-alpha mRNA levels in peripheral blood mononuclear cells in 6 experimentally infected dogs that exhibited different progressions of the illness. While in two dogs no parasite, or a very low number of parasites, was detected and the two dogs did not show any clinico-pathological abnormalities at the end of the study (L dogs), for the remaining dogs high parasite loads were detected and they developed clinical leishmaniasis (H dogs). The L dogs have null expression of both IL-4 and IL-13 for the first 4 months after the infection, whereas an early IL-4 and IL-13 expression occurs in this period of infection in most of the dogs that developed clinical leishmaniasis (H dogs). Furthermore, a higher IFN-gamma expression was associated with the increase of parasite load and clinical status in these dogs. Moreover, the high variability of expression at the pre-infection stage causes us to reject the possibility that the basal levels of these cytokines indicate the prognosis of the subsequent response against infection.

Selection in the making: a worldwide survey of haplotypic diversity around a causative mutation in porcine IGF2

Domestic species allow us to study dramatic evolutionary changes at an accelerated rate due to the effectiveness of modern breeding techniques and the availability of breeds that have undergone distinct selection pressures. We present a worldwide survey of haplotype variability around a known causative mutation in porcine gene IGF2, which increases lean content. We genotyped 34 SNPs spanning 27 kb in 237 domestic pigs and 162 wild boars. Although the selective process had wiped out variability for at least 27 kb in the haplotypes carrying the mutation, there was no indication of an overall reduction in genetic variability of international vs. European local breeds; there was also no evidence of a reduction in variability caused by domestication. The haplotype structure and a plot of Tajima's D against the frequency of the causative mutation across breeds suggested a temporal pattern, where each breed corresponded to a different selective stage. This was observed comparing the haplotype neighbor-joining (NJ) trees of breeds that have undergone increasing selection pressures for leanness, e.g., European local breeds vs. Pietrain. These results anticipate that comparing current domestic breeds will decisively help to recover the genetic history of domestication and contemporary selective processes.

[Intrapretosal schwannomas of facial nerve]

The aim of this study was to determine the factors that are important to the diagnosis and treatment of facial neuroma. The most common tumors of the peripheral nerves are the neurinomas; about 50% of them are found in the head and neck region. Among them, the most frequent is the VIII nerve tumor, while the facial neuroma is extremely rare. Neuromas can be intracraneal, intratemporal and extratemporal. The last one has a higher frequency. We present our experience in the intrapetrosal facial neuromas; usually showing different presentation symptoms wich is a characteristic of them. Retrospective study that was carried out at a private tertiary referral center. 3 patients were referred from other centers for otological surgery. One of them had symptoms of chronic otitis media, the second one was diagnosed of a glomus tumor and the last one showed a facial palsy. All the patients were operated on and then the facial nerve was repaired. Two patients had an end to end anastomosis, and in the other one we managed to keep the integrity of the facial nerve. The Hous -Brackmann facial grading scale was used. Two patients had grade II and the other grade III in this scale in the long-term follow up.

Clinical manifestations and hormonal profile of two women with Cushing's disease and mild deficiency of 21-hydroxylase

The development of Cushing's disease among patients with deficiency of 21-hydroxylase has not been observed to date. The clinical manifestations and the hormonal profile of this exceptional association are herein described through the study of two cases. The first one was a 39-yr-old woman who had undergone non-curative transsphenoidal surgery for a pituitary-dependent Cushing's syndrome 12 yr before. She showed hypertension, central obesity, severe hirsutism, alopecia and hyperpigmentation. Urinary excretion of cortisol was normal, but ACTH levels were very high and hormonal dynamic studies (cortisol circadian rhythm, insulin-induced hypoglycemia and dexamethasone suppression tests) revealed the qualitative disturbances that characterize Cushing's disease. Serum concentrations of androstenedione, free testosterone and 17-hydroxyprogesterone were clearly increased. Reexamination of the tissue samples from previous surgery confirmed the presence of an ACTH-producing pituitary adenoma. CYP21 gene analysis found the splicing 655G mutation at intron 2 and the V281L mutation at exon 7. The second case was a 21-yr-old woman who was diagnosed with pituitary ACTH-dependent Cushing's syndrome according to unequivocal clinical and laboratory findings. However, hirsutism was particularly severe and both serum androgens and 17-hydroxyprogesterone were elevated. The patient was heterozygote for a large conversion of CYP21 gene. In these cases, the clinical and biochemical expression of Cushing's syndrome was determined by the different severity of 21-hydroxylase deficiency and the subsequent residual ability of adrenal cortex to synthesize cortisol.

[Central diabetes insipidus as clinical presentation of a bronchogenic adenocarcinoma]

Metastatic tumors of the pituitary gland are uncommon. The majority of them are silent lesions incidentally discovered at autopsy. In contrast, the occurrence of symptomatic metastases is exceptional. Here we report the clinical and radiological findings of a 45 year-old woman with a metastatic lung adenocarcinoma who presented with diabetes insipidus and hypernatremic dehydration. There was no previous history of malignancy, and the pituitary metastases were responsible for the first manifestation of the disease. Clinical presentation, diagnosis and therapeutic management of patients with pituitary metastases are reviewed.

[In vitro comparative activity of moxifloxacin and other antimicrobials against respiratory pathogens]

BACKGROUND

Respiratory pathogens are becoming increasingly resistant to antimicrobials. A new group of drugs, called respiratory quinolones have been synthesized to overcome this problem.

AIM

To study the in vitro susceptibility of respiratory pathogens to old and new antimicrobials.

MATERIALS AND METHODS

Forty five strains of S pneumoniae, 44 strains of H influenzae, 21 strains of M catarrhalis, 10 strains of methicillin susceptible S aureus and 20 strains of methicillin resistant S aureus were studied. All were isolated from community acquired respiratory infections during 1999. Minimal inhibitory concentrations of moxifloxacin, amoxicillin, amoxicillin/clavulanic acid, clarithromycin, azithromycin, ciprofloxacin and levofloxacin were determined using the Etest method. Beta-lactamase production by H influenzae and M catarrhalis was also studied.

RESULTS

S pneumoniae strains were 100% susceptible to quinolones and cotrimoxazole, 2% were resistant to macrolides, 11% were resistant to amoxicillin/clavulanic acid and 47% were resistant to cefuroxime. H influenzae was 100% susceptible to quinolones, azithromycin and amoxicillin/clavulanic acid. There was a 53% resistance to cotrimoxazole, 21% to amoxicillin, 9% to clarithromycin and 7% to cefuroxime. M catarrahalis was 100% susceptible to quinolones and 100% resistant to amoxicillin, 5% resistant to macrolides, 14% resistant to amoxicillin/clavulanic acid, 20% to cefuroxime and 30% to cotrimoxazole. Methicillin susceptible S aureus was susceptible to all antimicrobials and methicillin resistant S aureus was resistant to all.

CONCLUSIONS

Maxifloxacin and the new respiratory quinolones can be useful in the treatment of respiratory infections.

[Emergence of resistance to macrolides in Streptococcus pyogenes]

BACKGROUND

Diseases produced by Streptoccocus pyogenes are still a problem in Chile, as in the rest of the world. It exhibits in vitro susceptibility to different antimicrobials, but penicillin continues to be the treatment of choice. Alternative drugs have been developed for allergic patients, such as erythromycin, new macrolides and cephalosporins. Nevertheless, resistant strains are appearing due to the indiscriminate use of macrolides.

AIM

To assess present antimicrobial susceptibility of S Pyogenes strains isolated from chilean patients.

MATERIAL AND METHODS

The susceptibility to penicillin, macrolides, clindamycin, cephalotin and vancomycin of 153 S Pyogenes strains, obtained from different health centers of the Metropolitan Region and isolated between 1996 and 1998, was assessed using the Kirby-Bauer method. Agar dilution minimal inhibitory concentration was then determined to macrolide resistant strains.

RESULTS

All strains were susceptible to penicillin. There was a 7.2% cross-resistance to macrolides.

CONCLUSIONS

These results confirm that S Pyogenes resistance to macrolides has increased considerably in the Metropolitan Region of Chile during the last years.

[Antimicrobial resistance of agents causing urinary tract infections in 11 Chilean hospitals. PRONARES project]

BACKGROUND

The computer program WHONET generates a common database to analyze local or general antimicrobial resistance of bacteria. A surveillance of agents causing urinary tract infections in Chile has been performed using this program.

AIM

To report the results after 12 months of urinary tract infection agent surveillance.

MATERIAL AND METHODS

Since November, 1997, a surveillance of in vitro antimicrobial resistance, using agar diffusion techniques, has been performed in 20 to 40 bacterial strains per month, isolated from 11 hospitals in the country. Results have been analyzed using WHONET program.

RESULTS

In first 12 months, 3144 strains, 1625 coming from outpatients, have been studied. Seventy four percent of isolated strains were E coli, 19% were other enterobacteria, 4.1% were non fermenting bacilli and 2.1% were Gram (+) cocci. Sixty five percent of E coli strains were resistant to ampicillin, 11% to cefazolin, 2.5% to cefuroxime, 19% to ceftriaxone, 9% to ceftazidime, 4.2% to gentamicin 1.3% to amikacin, 5.6% to ciprofloxacin, 8.4% to grepafloxacin, 4.3% to nitrofurantoin and 43% to trimeproprim/sulphamethoxazole. Eighty two percent of other enterobacteria strains were resistant to ampicillin, 45.5% to cefazolin, 33.5% to cefuroxime, 26.6% to ceftriaxone, 21.5% to ceftazidime, 30.3% to gentamicin 17.2% to amikacin, 21% to ciprofloxacin, 16.3% to grepafloxacin, 48.2% to nitrofurantoin and 44.6% to trimeproprim/sulphamethoxazole. There were differences in betalactamic resistance among hospitals.

CONCLUSIONS

Noteworthy is the high resistance rates to third generation cephalosporins, evidenced when the new cutoff values for E coli and Klebsiella spp are used. This national surveillance provides updated information on antimicrobial resistance of agents causing urinary tract infections.

Blood metabolites and their relationship with production variables in dual-purpose cows in Venezuela

A survey was carried out on 79 lactating Bos taurus/indicus cross-bred cows on three dual-purpose cattle farms to measure the blood concentration of metabolites and to evaluate possible relationships with nutritional status and productive variables. A rotational grazing system on Star grass and other tropical pastures (10-12% CP in leaves) was used and 2-3 kg/cow/day of concentrate were fed on two farms. Restricted calf suckling was used in two herds. Average milk yield sold per farm was 6 kg/day/cow and body condition scores (BCS) were between 3.0 and 3.8 on a scale of one-to-five. On two farms, the average interval from calving to conception (ICC) was more than 145 days. Mean blood concentrations of albumin, globulin, urea, beta-hydroxybutyrate and phosphorus were generally within reference values, but a significant group of cows had low levels of albumin and urea and high levels of globulin. Packed cell volume (PCV) was below normal values, with anemia in 63% of cows during the second trimester of lactation, which was negatively correlated to milk yield. The high incidence of anemia could be related to factors such as hematophagic parasites, not evaluated in this study. ICC values were negatively related to albumin level and could be associated with protein deficiency in the diet or with disease, as globulin values were high in many cows. Based on these diagnoses, an experiment was carried out on one of the farms to evaluate the influence of supplementation with 0.5 kg/cow/day of fish meal. Total milk yield was not influenced by the fish meal and reproductive efficiency was high in the two supplemental treatments. It was shown that supplementation with undergraded protein is not required in these cows.

Allergic reactions following skin contact with fish

We evaluated the clinical characteristics found in 29 children who showed allergic symptoms after direct and/or indirect contact with fish, from 197 children diagnosed with IgE-mediated fish hypersensitivity. Allergic reactions to fish through ingestion began in most patients (79%) within the first 24 months of life. All the patients showed cutaneous symptoms, either alone or associated with other clinical manifestations. Whiff and hake were the species more frequently implicated in eliciting clinical manifestations upon ingestion. After diagnosis, all patients were placed on a strict fish avoidance diet. During this period of avoidance, 29 patients reported allergic reactions (mean age 5 years, 6 months; SD 4 years, 2 months) after incidental skin contact with fish. Clinical manifestations after touching fish were only cutaneous in 28 of the 29 studied patients. One showed local urticaria with wheezing. The majority reported two or more episodes. Incidental skin contact with fish could play an important role in accidental encounters with fish particles in children on a fish avoidance diet for fish IgE-mediated hypersensitivity. Such exposures could result in immunologic immediate contact reactions and in some cases could lead to systemic reactions (contact urticaria syndrome).

Sorbitol-negative phenotype among enterohemorrhagic Escherichia coli strains of different serotypes and from different sources

Enterohemorrhagic Escherichia coli (EHEC) strains detected with DNA probes (for virulence plasmid and Shiga-like toxins) from subjects with hemolytic-uremic syndrome (n = 19) or diarrhea (n = 41) or asymptomatic carriers (n = 29) were examined for sorbitol fermentability, as were enterotoxigenic (n = 40), enteropathogenic (n = 40), and enteroinvasive (n = 40) E. coli and urinary tract infection (n = 40) strains and normal flora E. coli strains (n = 40). Sorbitol negativity was common only in EHEC, particularly among strains from severe clinical infections. All 19 EHEC strains from patients with hemolytic-uremic syndrome, irrespective of O:H serotype or Shiga-like toxin genotype, were sorbitol negative.

Relationship between pollinosis and fruit or vegetable sensitization

The prevalence of vegetable sensitization in children with pollinosis (Group A; n = 48) and the prevalence of pollen sensitization in children with fruit or vegetable allergy (Group B; n = 42) were studied by means of prick-test and determination of serum specific IgE to several pollens, fruits and vegetables. Fifteen patients from Group A (31%) showed sensitivity to fruits and/or vegetables, but only three of them had any symptoms after ingestions. Twenty nine patients from Group B (69%) showed pollen sensitization, mainly to grass and Compositae pollen. An association was found between sensitivity to Compositae pollen and sensitivity to several fruits and vegetables (Compositae, Fagaceae, Brassica, Betulaceae and Leguminoseae).

Dexamethasone-suppressible feminizing adrenal adenoma

A 39 year old man presented with gynaecomastia, loss of libido and high blood pressure. Hormone studies revealed elevated plasma levels of oestradiol and its precursors, which increased in response to adrenocorticotrophic hormone and were reduced to normal levels with dexamethasone. Computed tomography disclosed a left adrenal mass and surgery was performed. The removed tumour weighed 84 g and the histological diagnosis was of adenoma. Nine years after surgery, he is asymptomatic, without hypertension, and radiological and or hormonal evidence of recurrence. We discuss the hormone profile in this case and the dynamics of steroid production by the tumour which, in contrast to the classical concept of tumour autonomy, showed dependence of oestradiol secretion on endogenous adrenocorticotrophic hormone.

Double-blind, randomized clinical trial on the effect of interferon-beta in the treatment of condylomata acuminata

A randomized, double-blind, placebo-controlled trial was conducted to assess interferon-beta efficacy and safety in the treatment of anogenital condylomatous lesions. One hundred patients received a daily intramuscular injection of either interferon-beta (IFN-beta) (2 MIU/day) or placebo for 10 days. Of 94 evaluable patients, the complete response rate observed 8 weeks after treatment was significantly higher in the group receiving IFN-beta, as compared to the placebo-treated group (51% vs 28.9%, P < 0.05). After one year, 24 patients (100%) out of 24 complete responders to IFN-beta who attended for follow-up remained free of lesions. Twelve of 13 patients with complete response to placebo (92.3%) remained free of lesions after one year. Side effects were mild and no significant analytical changes were observed. In conclusion, interferon-beta is an effective and safe treatment for long-term eradication of anogenital condylomatous lesions.

Lymphocytic hypophysitis causing hypopituitarism and diabetes insipidus, and associated with autoimmune thyroiditis, in a non-pregnant woman

A 25 year old non-pregnant woman presented with a one-year history of amenorrhoea and polyuria. Three months before her admission, she had suffered lymphocytic meningitis. Hormonal studies revealed hypopituitarism and central diabetes insipidus, with associated primary autoimmune hypothyroidism. Computed tomographic scan and magnetic resonance imaging showed a pituitary mass with suprasellar extension and thickened stalk. Transsphenoidal surgery was performed and the histological study revealed fibrosis and diffuse lymphocytic infiltration with predominance of CD4 lymphocytes. This further case of lymphocytic hypophysitis was not related to pregnancy and produced diabetes insipidus, two uncommon associations. We discuss the features that can lead to a preoperative suspicion of this rare disorder.