Genetic Diversity of the Amur Tiger (Panthera tigris altaica): Are There Differences between the 20th and the Early 21st Centuries?

Polymorphism of nine microsatellite loci in the Sikhote-Alin tiger population was analyzed in the modern and recent historical periods, using blood, excrement, and museum bone samples. Tests for excess heterozygosity to determine whether the population went through a period of low abundance and a low value of the Garza-Williamson coefficient indicated that such events were highly probable to occur in both recent and earlier history. The mean effective population size Ne of a current sample was 34.4 (95% confidence interval 17-106.8). This fact is of great interest in the contest of conservation and restoration of endangered large cat species.

Entamoeba histolytica induces human neutrophils to form NETs.

Entamoeba histolytica invades the intestine and other organs during the pathogenesis of amoebiasis. In the early stages, the host organism responds with an inflammatory infiltrate composed mostly of neutrophils. It has been reported that these immune cells, activated by E. histolytica, exert a protective role by releasing proteolytic enzymes and generating reactive oxygen/nitrogen species (ROS/RNS) and antimicrobial peptides. It is now known that neutrophils also produce neutrophil extracellular traps (NETs), which are able to damage and kill pathogens. Studies have shown that intracellular protozoan pathogens, including Toxoplasma gondi, Plasmodium falciparum and Leishmania spp, induce neutrophils to release NETs and are damaged by them. However, the action of this mechanism has not been explored in relation to E. histolytica trophozoites. Through scanning electron, epifluorescence microscopy and viability assays, we show for first time that during in vitro interaction with E. histolytica trophozoites, human neutrophils released NETs that covered amoebas and reduced amoebic viability. These NETs presented histones, myeloperoxidase and decondensed chromatin. The results suggest that NETs participate in the elimination of the parasite.

Scrutinizing the role of size reduction on the exchange bias and dynamic magnetic behavior in NiO nanoparticles.

NiO nanoparticles (NPs) with a nominal size range of 2-10 nm, synthesized via high-temperature pyrolysis of a nickel nitrate, have been extensively investigated using neutron diffraction and magnetic (ac and dc) measurements. The magnetic behavior of the NPs changes noticeably when their diameter decreases below 4 nm. For NPs larger than or equal to this size, Rietveld analysis of the room temperature neutron diffraction patterns reveals that there is a reduction in the expected magnetic moment per [Formula: see text] ion with respect to bulk NiO, which is linked to the existence of a magnetically disordered shell at the NP surface. The presence of two peaks in the temperature dependence of both the dc magnetization after zero-field-cooling and the real part of the ac magnetic susceptibility is explained in terms of a core (antiferromagnetic, AFM)/shell (spin glass, SG) morphology. The high-temperature peak ([Formula: see text] K) is associated with collective blocking of the uncompensated magnetic moments inside the AFM core. The low-temperature peak ([Formula: see text] K) is a signature of a SG-like freezing of the surface [Formula: see text] spins. In addition, an exchange bias (EB) effect emerges due to the core/shell magnetic coupling. The cooling field and temperature dependences of the EB effect and the coercive field are discussed in terms of the core size and the effective magnetic anisotropy of the NPs. However, NiO NPs of 2 nm in size no longer show AFM order and the [Formula: see text] magnetic moments freeze into a SG-like state below [Formula: see text] K, with no evidence of EB effect.

[Diagnosing pneumothorax with ultrasonography]. / Diagnóstico ecográfico del neumotórax.

The ultrasonographic diagnosis of pneumothorax is based on the analysis of artifacts. It is possible to confirm or rule out pneumothorax by combining the following signs: lung sliding, the A and B lines, and the lung point. One fundamental advantage of lung ultrasonography is its easy access in any critical situation, especially in patients in the intensive care unit. For this reason, chest ultrasonography can be used as an alternative to plain-film X-rays and computed tomography in critical patients and in patients with normal plain films in whom pneumothorax is strongly suspected, as well as to evaluate the extent of the pneumothorax and monitor its evolution.

H1N1 virus infection: chest radiographic findings.

OBJECTIVE: To show the plain chest film findings in patients with confirmed infection with the new variant of the influenza A (H1N1) virus and to correlate these findings with the clinical history and evolution. MATERIAL AND METHODS: We reviewed the clinical histories and radiological studies in 99 patients infected with the new variant of H1N1 influenza who were admitted in two Hospitals in Cantabria, Spain. Plain chest film findings were classified according to their parenchymal pattern and the distribution of the lesions. RESULTS: Of the 99 patients evaluated, 28 had changes on the plain chest film acquired at admission. In these 28 patients, the findings were: condensation in 19, condensation and ground-glass opacities in 7, and ground-glass opacities in 2; the distribution of the lesions was diffuse in 17 patients and bilateral in 17, with the lower and middle lobes being the most frequently affected. The lesions progressed in 13 patients, and the 7 patients who required mechanical ventilation had a higher frequency of diffuse lesion distribution and more lung fields affected on the plain chest field acquired at admission. Pathological findings on plain chest films were more common in males, in smokers, and in patients who presented with shortness of breath, pleuritic pain, and diarrhea (P<0.05). CONCLUSION: Most patients infected with the new variant of the H1N1 virus had no alterations on the plain chest film acquired on admission; when findings were present, the predominant pattern was diffuse, bilateral condensation mainly involving the bases of the lungs. Pleural effusion and hilar or mediastinal lymph node enlargement were uncommon.

Magnetic order and disorder environments in superantiferromagnetic [Formula: see text] nanoparticles.

Magnetic nanoparticles exhibit two different local symmetry environments, one ascribed to the core and one corresponding to the nanoparticle surface. This implies the existence of a dual spin dynamics, leading to the presence of two different magnetic arrangements governed by different correlation lengths. In this work, two ensembles of [Formula: see text] nanoparticles with mean sizes of 18 nm and 13 nm have been produced to unravel the magnetic couplings established among the magnetic moments located within the core and at the nanoparticle surface. To this end, we have combined neutron diffraction measurements, appropriate to investigate magnetically-ordered spin arrangements, with time-dependent macroscopic AC susceptibility measurements to reveal memory and aging effects. The observation of the latter phenomena are indicative of magnetically-frustrated states. The obtained results indicate that, while the [Formula: see text] magnetic moments located within the nanoparticle core keep the bulk antiferromagnetic commensurate structure in the whole magnetic state, the correlations among the surface spins give rise to a collective frustrated spin-glass phase. The interpretation of the magnetic structure of the nanoparticles is complemented by specific-heat measurements, which further support the lack of incommensurability in the nanoparticle state.

[Venous embolization--treatment of choice in varicoceles]. / La embolización venosa, tratamiento de elección en los varicoceles.

Varicocele consists of the varicose expansion of the spermatic vein. It's more frequently in the left side (10:1) as consequence of an evil functioning or absence of the valves of the spermatic left vein. Between March 1999 and December 2009 there have been gathered a total of 37 cases diagnosed of varicocele in the pediatric population of our center. After a local anesthetic we created a femoral aproach. We advance into the left renal vein using a catheter Simmons type I and then we position the top of the catheter beyond the ostium of the spermatic vein to fulfil the renal left vein by means of the administration of contrast iodized and gonadal vein could be visualized using retrograde phlebography. Transcatheter embolization will carry out across the introduction of coils (approximately from 6 to 8) of 0.038 using a hidrofilic catheter of 4 or 5F. Of the total of the 37 cases, we obtained correctly embolization in 33 patients (89.2%), being necessary a reembolization in three cases (10.8%) of which one finished in surgery. Only in a case (2.7%) surgery was practised for embolization incomplete.

Year of the face mask: do's and don'ts during exercise.

The COVID-19 pandemic causes widespread anxiety and uncertainty regarding disease transmission. In many countries people are obliged to wear a face mask in public spaces. Individuals involved in sports participation at any level need to make informed decisions on wearing a face mask during exercise. Currently there is no scientific evidence on what to advise regarding the safety of wearing a face mask during exercise, or what type of mask to use. This short report aims to answer these questions in a structured and practical way.

[Statin treatment as primary prevention in dyslipidaemic patients older than 75 years]. / Tratamiento con estatinas en pacientes dislipidémicos mayores de 75 años, en prevención primaria.

OBJECTIVES: To determine possible differences in the incidence of cardiovascular events between dyslipidaemia patients older than 75 years treated with statins compared to those not treated with them, as primary prevention. MATERIAL AND METHODS: A retrospective cohort study was conducted in patients older than 75 years with dyslipidaemia in a health centre, between 2005 and 2015. The study included 329 patients (182 on treatment with statins and 147 with no lipid-lowering treatment) who met the inclusion criteria (patients older than 75 years, on treatment with statins for at least 3 years, or to have not had any lipid lowering treatment and as primary prevention). The study variables were all those considered as a risk factor in the latest cardiovascular risk guidelines, and the dependent variable was "cardiovascular event". A descriptive and inferential analysis was carried out for quantitative and qualitative variables, as well as a multivariate analysis using binary logistic regression. RESULTS: The incidence of cardiovascular events in patients without treatment with statins was 15.93% (95% CI 11.15-21.80), and 37.42% (95% CI 29.87-45.45) in those that were taking them (P<.001). The RR was 2.35 (95% CI 1.58-3.48). CONCLUSIONS: There are statistically significant differences, with an increase in the incidence of cardiovascular events in patients taking statins, compared to those who do not. It is currently considered whether real importance is being given to cholesterol levels in this patient group, as well as whether the prescription of statins in patients older than 75 years is suitable in primary prevention.

Human amniotic membrane intra-articular injection prevents cartilage damage in an osteoarthritis model.

Osteoarthritis (OA) is a degenerative joint disease that affects the soft tissues and bones of involved articulations as a result of deregulation between synthesis and extracellular matrix degradation in articular cartilage. The present study evaluated the effect of intra-articular injection of human amniotic membrane (AM) as a treatment in an OA animal model in the knee. Chemical OA was developed in the knees of New Zealand rabbits. Once OA was established, the right knees only were treated with an intra-articular injection of human AM, with the left knees considered as a negative control group. The evaluation was performed at 3 and 6 weeks post-treatment. At 3 weeks post-injection, the cartilage exhibited fibrillation, erosion, cracks and cell clusters in the negative control group, but not in the treated group (P=0.028). At 6 weeks post-injection, the left knees exhibited hypertrophy, cracks, cell clusters, decreased matrix staining and structure loss. However, the right knees exhibited cell clusters without evidence of disruption in cartilage integrity (P=0.015). These results suggested that the intra-articular injection of human AM delays histological changes of cartilage in OA.

Current concepts on the pathophysiology of idiopathic chronic adult hydrocephalus: Are we facing another neurodegenerative disease? / Actualización en la fisiopatología de la hidrocefalia crónica del adulto idiopática: ¿nos enfrentamos a otra enfermedad neurodegenerativa?

INTRODUCTION: Since its description five decades ago, the pathophysiology of idiopathic chronic adult hydrocephalus (iCAH) has been traditionally related to the effect that ventricular dilatation exerts on the structures surrounding the ventricular system. However, altered cerebral blood flow, especially a reduction in the CSF turnover rate, are starting to be considered the main pathophysiological elements of this disease. DEVELOPMENT: Compression of the pyramidal tract, the frontostriatal and frontoreticular circuits, and the paraventricular fibres of the superior longitudinal fasciculus have all been reported in iCAH. At the level of the corpus callosum, gliosis replaces a number of commissural tracts. Cerebral blood flow is also altered, showing a periventricular watershed region limited by the subependymal arteries and the perforating branches of the major arteries of the anterior cerebral circulation. The CSF turnover rate is decreased by 75%, leading to the reduced clearance of neurotoxins and the interruption of neuroendocrine and paracrine signalling in the CSF. CONCLUSIONS: iCAH presents as a complex nosological entity, in which the effects of subcortical microangiopathy and reduced CSF turnover play a key role. According to its pathophysiology, it is simpler to think of iCAH more as a neurodegenerative disease, such as Alzheimer disease or Binswanger disease than as the classical concept of hydrocephalus.

Persistent alterations in colonic afferent innervation in a rat model of postinfectious gut dysfunction: Role for changes in peripheral neurotrophic factors.

BACKGROUND: Visceral hypersensitivity in the inflamed gut is related partly to the effects of peripheral neurotrophic factors (NTFs) on local afferent neurons. However, alterations in sensory afferents of distant areas remain unexplored. Using the Trichinella spiralis infection model, which causes a jejunitis, we investigated the remodeling of colonic afferents and the potential role of NTFs. METHODS: Rats were infected with T. spiralis. Inflammatory-like changes, mucosal mast cells (MMCs) dynamics, and expression of nerve growth factor and glial cell line-derived NTFs (glial cell-derived neurotrophic factor, artemin, and neurturin) were determined in the colon up to day 30 postinfection. Functional responses of colonic afferents were determined assessing changes in the expression of sensory-related markers in thoracolumbar (TL)/lumbosacral (LS) dorsal root ganglias (DRGs) following intracolonic capsaicin. KEY RESULTS: Trichinella spiralis induced an inflammatory-like response within the colon, partly resolved at day 30 postinfection, except for a persistent MMC infiltrate. While the jejunum of infected animals showed an up-regulation in the expression of NTFs, a transitory down-regulation was observed in the colon. Overall, T. spiralis effects on DRGs gene expression were restricted to a transient down-regulation of TPRV1. Stimulation with intracolonic capsaicin induced a down-regulation of TRPV1 levels in TL and LS DRGs, an effect enhanced in LS DRGs of infected animals, regardless the postinfection time considered. CONCLUSIONS & INFERENCES: During intestinal inflammation, spread morphological and functional alterations, including remodeling of visceral afferents, are observed outside the primary region affected by the insult. Similar mechanisms might be operating in states of widespread alterations of visceral sensitivity.

Boosted Hyperthermia Therapy by Combined AC Magnetic and Photothermal Exposures in Ag/Fe3O4 Nanoflowers.

Over the past two decades, magnetic hyperthermia and photothermal therapy are becoming very promising supplementary techniques to well-established cancer treatments such as radiotherapy and chemotherapy. These techniques have dramatically improved their ability to perform controlled treatments, relying on the procedure of delivering nanoscale objects into targeted tumor tissues, which can release therapeutic killing doses of heat either upon AC magnetic field exposure or laser irradiation. Although an intense research effort has been made in recent years to study, separately, magnetic hyperthermia using iron oxide nanoparticles and photothermal therapy based on gold or silver plasmonic nanostructures, the full potential of combining both techniques has not yet been systematically explored. Here we present a proof-of-principle experiment showing that designing multifunctional silver/magnetite (Ag/Fe3O4) nanoflowers acting as dual hyperthermia agents is an efficient route for enhancing their heating ability or specific absorption rate (SAR). Interestingly, the SAR of the nanoflowers is increased by at least 1 order of magnitude under the application of both an external magnetic field of 200 Oe and simultaneous laser irradiation. Furthermore, our results show that the synergistic exploitation of the magnetic and photothermal properties of the nanoflowers reduces the magnetic field and laser intensities that would be required in the case that both external stimuli were applied separately. This constitutes a key step toward optimizing the hyperthermia therapy through a combined multifunctional magnetic and photothermal treatment and improving our understanding of the therapeutic process to specific applications that will entail coordinated efforts in physics, engineering, biology, and medicine.

Síndrome de Hamman como complicación inusual de COVID-19 / Hamman syndrome as an unusual complication of covid-19

La enfermedad por SARS-CoV-2 ha sido bien conocida por su capacidad de infección y afectación multiórgano con cierta preferencia y gravedad a los pulmones incluyendo lesiones parenquimatosas, alveolares e intersticiales. En esta oportunidad se presenta un caso infrecuente como lo es el síndrome de Hamman en un paciente masculino de 35 años con neumonía viral por COVID-19, Entidad que podría ser un indicador potencial de progresión y agravante de la enfermedad como de los síntomas asociados al patrón usual de la infección. Su tratamiento lo definirá la estabilidad clínica y el tamaño del neumomediastino (AU)

SARS-CoV-2 disease has been well known for its capacity for infection and multi-organ involvement with some preference and severity to the lungs including parenchymal, alveolar and interstitial lesions. On this occasion, an infrequent case such as Hamman syndrome is presented in a 35-year-old male patient with viral pneumonia due to COVID-19. Entity that could be a potential indicator of progression and aggravation of the disease as well as the symptoms associated with the pattern usual infection. His treatment will define the clinical stability and size of the pneumomediastinum (AU)

Formation of open and elongating transcription complexes by RNA polymerase III.

The Saccharomyces cerevisiae transcription factors (TF) IIIB and IIIC assemble onto their respective DNA-binding sites on the SUP4 tRNA(Tyr) gene at 0 degrees C. RNA polymerase III specifically associates at 0 degrees C with this TFIIIC-TFIIIB-DNA complex to form a stable "closed" promoter complex in which the DNA surrounding the transcriptional start retains its duplex form. Promoter "opening" is a temperature-dependent and readily reversible process that involves up to 22 unwound base-pairs of DNA, and can be followed by analyzing the hyperreactivity of thymine to KMnO4 oxidation. This promoter opening increases progressively from 10 degrees C to 40 degrees C, with at least two regions within the transcription bubble appearing to melt independently. In contrast, the temperature dependence of forming an initiated transcription complex containing a 17 nucleotide nascent RNA chain displays a sharp transition between 10 degrees C and 15 degrees C. When RNA polymerase initiates transcription under conditions that limit the nascent RNA chain to less than six nucleotides, there is no displacement of the transcription bubble. These transcription complexes are distinguishable from "open" promoter complexes in their maintenance of the transcription bubble at 0 degrees C, and from transcription complexes with more extended (17 nucleotide) RNA chains in their sensitivity to disruption by heparin. In light of recent results by others that demonstrate a requirement for an RNA transcription factor in a Bombyx mori-based in vitro RNA polymerase III transcription system, we have searched for a comparable component in the S. cerevisiae-derived system. We show that if an RNA component is required in the yeast-derived system, it is not susceptible to inactivation by massive amounts of micrococcal nuclease, RNase A, or RNase T1.

[Laparoscopy in chronic abdominal pain in children]. / La laparoscopia en el dolor abdominal crónico en la infancia.

UNLABELLED: The recurrent chronic abdominal pain (RAP) is one of the most usual pathologies in pediatrics. It may appear in the form of periodical or continuous sharp crisis. In order to be accepted as chronic, the presence of this pain must last at least 3 months. In many of the reference publications, only between 5 and 1% of the cases are considered to have an organic ethiology and the rest are labelled as functional processes of psychological origin. The reason for our communication is to show our experience on 304 RAP patients from 1995 to 2001. We also want to highlight the usefulness of laparoscopy in order to diagnose and treat 14.45% (44) of cases of this group of patients. MATERIAL AND METHODOLOGY: 304 patients between 5 and 14 years old were studied from 1995 to 2001. We followed a protocol of: medical and personal medical record, specific anamnesis for RAP, detailed description of the diet and intestinal habits, physical exploration. Laboratory: 1) blood analysis, hepatic profile, glucose, cholesterol, creatinine, amylase, 2) urine sediment and may be urine culture, 3) faeces analysis and 4) vaginal flow analysis. Image diagnosis is: simple abdomen radiography, ultrasonography and intestinal Rx. Guided and specific determinations: spired urea test, gastric chemism, lactose test, gastroscopy and biopsy, colonoscopy and biopsy, laparoscopy. RESULTS: In short, we can say: 74 patients (23.4%) come with inappropiate feeding diets, 31 (10.1%) with helicobacter pilori, 20 (6.5%) with adenoids, pharynx and pharyngeal processes, the same figure from gynaecologic origin, 18 (5.9%) from psychological origin, and in 44 cases (14.45%) laparoscopy was indicated. CONCLUSIONS: The anatomopathological study in the cases in which we carried out laparoscopic appendicectomy does not allow us to accept the symptoms of chronic appendicitis. The exploratory laparoscopy and the appendectomy have meant benefits for the solution to this pathology in 14.45% of patients. It is essential to carry out a long-term follow-up, at least 12 months, to be sure RAP is cured. We must carry on looking for aetiological cause of RAP.

Magnetic phase diagram of superantiferromagnetic TbCu2 nanoparticles.

The structural state and static and dynamic magnetic properties of TbCu2 nanoparticles are reported to be produced by mechanical milling under inert atmosphere. The randomly dispersed nanoparticles as detected by TEM retain the bulk symmetry with an orthorhombic Imma lattice and Tb and Cu in the 4e and 8h positions, respectively. Rietveld refinements confirm that the milling produces a controlled reduction of particle sizes reaching ≃6 nm and an increase of the microstrain up to ≃0.6%. The electrical resistivity indicates a metallic behavior and the presence of a magnetic contribution to the electronic scattering which decreases with milling times. The dc-susceptibility shows a reduction of the Néel transition (from 49 K to 43 K) and a progressive increase of a peak (from 9 K to 15 K) in the zero-field-cooled magnetization with size reduction. The exchange anisotropy is very weak (a bias field of ≃30 Oe) and is due to the presence of a disordered (thin) shell coupled to the antiferromagnetic core. The dynamic susceptibility evidences a critical slowing down in the spin-disordered state for the lowest temperature peak associated with a spin glass-like freezing with a tendency of zv and ß exponents to increase when the size becomes 6 nm (zv ≃ 6.6 and ß ≃ 0.85). A Rietveld analysis of the neutron diffraction patterns 1.8 ≤ T ≤ 60 K, including the magnetic structure determination, reveals that there is a reduction of the expected moment (≃80%), which must be connected to the presence of the disordered particle shell. The core magnetic structure retains the bulk antiferromagnetic arrangement. The overall interpretation is based on a superantiferromagnetic behavior which at low temperatures coexists with a canting of surface moments and a mismatch of the antiferromagnetic sublattices of the nanoparticles. We propose a novel magnetic phase diagram where changes are provoked by a combination of the decrease of size and the increase of microstrain.