Intestinal inflammation marker calprotectin regulates epithelial intestinal zinc metabolism and proliferation in mouse jejunal organoids

Calprotectin (CP), a heterodimer of S100A8 and S100A9, is expressed by neutrophils and a number of innate immune cells and is used widely as a marker of inflammation, particularly intestinal inflammation. CP is a ligand for toll-like receptor 4 (TLR4) and the receptor for advanced glycation end products (RAGE). In addition, CP can act as a microbial modulatory agent via a mechanism termed nutritional immunity, depending on metal binding, most notably Zn2+. The effects on the intestinal epithelium are largely unknown. In this study we aimed to characterize the effect of calprotectin on mouse jejunal organoids as a model epithelium, focusing on Zn2+ metabolism and cell proliferation. CP addition upregulated the expression of the Zn2+ absorptive transporter Slc39a4 and of methallothionein Mt1 in a Zn2+-sensitive manner, while downregulating the expression of the Zn2+ exporter Slc30a2 and of methallothionein 2 (Mt2). These effects were greatly attenuated with a CP variant lacking the metal binding capacity. Globally, these observations indicate adaptation to low Zn2+ levels. CP had antiproliferative effects and reduced the expression of proliferative and stemness genes in jejunal organoids, effects that were largely independent of Zn2+ chelation. In addition, CP induced apoptosis modestly and modulated antimicrobial gene expression. CP had no effect on epithelial differentiation. Overall, CP exerts modulatory effects in murine jejunal organoids that are in part related to Zn2+ sequestration and partially reproduced in vivo, supporting the validity of mouse jejunal organoids as a model for mouse epithelium.

Estimating averted illnesses from influenza vaccination for children and pregnant women - El Salvador, Panama, and Peru, 2011-2018

BACKGROUND

Estimating the burden of disease averted by vaccination can assist policymakers to implement, adjust, and communicate the value of vaccination programs. Demonstrating the use of a newly available modeling tool, we estimated the burden of influenza illnesses averted by seasonal influenza vaccination in El Salvador, Panama, and Peru during 2011-2017 among two influenza vaccine target populations: children aged 6-23 months and pregnant women.

METHODS

We derived model inputs, including incidence, vaccine coverage, vaccine effectiveness, and multipliers from publicly available country-level influenza surveillance data and cohort studies. We also estimated changes in illnesses averted when countries' vaccine coverage was achieved using four different vaccine deployment strategies.

RESULTS

Among children aged 6-23 months, influenza vaccination averted an estimated cumulative 2,161 hospitalizations, 81,907 medically-attended illnesses, and 126,987 overall illnesses during the study period, with a prevented fraction ranging from 0.3 % to 12.5 %. Among pregnant women, influenza vaccination averted an estimated cumulative 173 hospitalizations, 6,122 medically attended illnesses, and 16,412 overall illnesses, with a prevented fraction ranging from 0.2 % to 10.9 %. Compared to an influenza vaccine campaign with equal vaccine distribution during March-June, scenarios in which total cumulative coverage was achieved in March and April consistently resulted in the greatest increase in averted illness (23 %-3,129 % increase among young children and 22 %-3,260 % increase among pregnant women).

DISCUSSION

Influenza vaccination campaigns in El Salvador, Panama, and Peru conducted between 2011 and 2018 prevented hundreds to thousands of influenza-associated hospitalizations and illnesses in young children and pregnant women. Existing vaccination programs could prevent additional illnesses, using the same number of vaccines, by achieving the highest possible coverage within the first two months of an influenza vaccine campaign.

Development and validation of a clinical score for early diagnosis of constipation in critically ill children

Constipation affects almost 50% of critically ill pediatric patients and is related to their morbidity and mortality. However, little attention is paid to it and it is diagnosed late and when there are already complications. The objective of this study is to develop and validate a score to identify critically ill children with high risk of constipation 48 h after admission. A single center two phase-study was carried out; the first one (retrospective observational study) to develop the score and the second one to validate it in another prospective observational study. Children between 15 days of life and 18 years old admitted to the PICU for more than 3 days were included. Demographic and clinical data during the first 48 h after PICU admission were collected. Univariate and multivariate analysis and ROC curves were used to develop and validate the score. Data from 145 patients (62.8% boys) with a mean age of 34.9 ± 7.3 months were used to develop the score. Independent factors identified to develop the score were: weight > 7 kg, admission to PICU after surgery, need of vasoconstrictors, doses of fentanyl ≥ 2 mcg/kg/h, and initiation of enteral nutrition later than 48 h after admission. Two cut-off values were identified to set low constipation risk (< 5.7 points) and high constipation risk (> 6.2 points). This score was validated in 124 patients showing a sensibility of 63.2%, specificity of 95.5% and a positive/negative predictive values (P/NPV) of 100% and 82.1% respectively to identify constipated patients. This is the first score to identify high constipation risk in critically ill children. This score is easy to apply, and internal validation has shown a PPV of 100%.

Estimation of the density of veins from susceptibility-weighted imaging by using Mamdani fuzzy-type rule-based system. Investigating the neurovascular coupling in migraine

BACKGROUND AND PURPOSE

An impaired neurovascular coupling has been described as a possible player in neurodegeneration and cognitive decline. Migraine is a recurrent and incapacitating disorder that starts early in life and has shown neurovascular coupling abnormalities. Despite its high prevalence, the physiology and underlying mechanisms are poorly understood. In this context, new biomarkers from magnetic resonance imaging (MRI) are needed to bring new knowledge into the field. The aim of this study was to determine the vein density from Susceptibility-Weighted Imaging (SWI) MRI, in subjects with migraine and healthy controls; and to assess whether it relates to Resting-State functional MRI (RS-fMRI).

MATERIALS AND METHODS

The cohort included 30 healthy controls and 70 subjects with migraine (26 episodic, 44 chronic) who underwent a brain 3.0 T MRI. Clinical characteristics were also collected. Maps of density of veins were generated based on a Mamdani Fuzzy-Type Rule-Based System from the SWI MRI. Mean values of vein density were obtained in grey (GM) and white matter (WM) Freesurfer lobar parcellations. The Amplitude of Low-Frequency Fluctuations (ALFF) image was calculated for the RS-fMRI, and the mean values over the parcellated GM lobes were estimated. Differences between groups were assessed through and analysis of variance (age, sex, education and anxiety as covariates; p < 0.05), followed by post-hoc comparisons. Associations were run between clinical and MRI-derived variables.

RESULTS

When comparing the density of veins in GM, no differences between groups were found, neither associations with clinical variables. The density of veins was significantly higher in the WM of the occipital lobe for subjects with chronic migraine compared to controls (30%, p < 0.05). WM vein density in either frontal, temporal or cingulate regions was associated with clinical variables such as headache days, disability scores, and cognitive impairment (r between 0.25 and 0.41; p < 0.05). Mean values of ALFF did not differ significantly between controls and subjects with migraine. Strong significant associations between vein density and ALFF measures were obtained in most GM lobes for healthy subjects (r between 0.50 and 0.67; p < 0.05), instead, vein density in WM was significantly associated with ALFF for subjects with migraine (r between 0.32 and 0.58; p < 0.05).

CONCLUSIONS

Results point towards an increase in vein density in subjects with migraine, when compared to healthy controls. In addition, the association between GM vein density and ALFF found in healthy subjects was lost in migraine. Taken together, these results support the idea of abnormalities in the neurovascular coupling in migraine. Quantitative SWI MRI indicators in migraine might be an interesting target that may contribute to its comprehension.

Incidence of respiratory virus illness and hospitalizations in a Panama and El Salvador birth cohort, 2014-2018

Background

Respiratory viruses remain a key cause of early childhood illness, hospitalization, and death globally.The recent pandemic has rekindled interest in the control of respiratory viruses among paediatric populations. We estimate the burden of such viruses among children <2 years.

Methods

Enrolled neonates were followed until two years of age. Weekly active symptom monitoring for the development of acute respiratory illnesses (ARI) defined as cough, rhinorrhoea, difficulty breathing, asthenia, anorexia, irritability, or vomiting was conducted. When the child had ARI and fever, nasopharyngeal swabbing was performed, and samples were tested through singleplex RT-PCR. Incidence of respiratory viruses was calculated by dividing the number of laboratory-confirmed detections by the person-time accrued during weeks when that virus was detectable through national surveillance then corrected for under-ascertainment among untested children.

Findings

During December 2014-November 2017, 1567 enrolled neonates contributed 2,186.9 person-years (py). Six in ten (64·4%) children developed ARI (total 2493 episodes). Among children <2 years, incidence of respiratory syncytial virus (RSV)-associated ARI episodes (21·0, 95%CI 19·3-22·8, per 100py) and rhinovirus-associated (20·5, 95%CI 20·4-20·7) were similar and higher than parainfluenza 1-3-associated (14·2, 95%CI 12·2-16·1), human metapneumovirus-associated (9·2, 95%CI 7·7-10·8), influenza-associated (5·9, 95%CI 4·4-7·5), and adenovirus-associated ARI episodes (5·1, 95%CI 5·0-5·2). Children aged <3 months had the highest rates of RSV ARI (49·1, 95%CI 44·0-54·1 per 100py) followed by children aged 3-5 (25·1, 95%CI 20·1-30·0), 6-11 (17·6, 95%CI 13·2-21·9), and 12-23 months (11·9, 95%CI 10·8-12·9). One in ten children with RSV was referred to the hospital (2·5, 95%CI 2·1-2·8, per 100py).

Interpretation

Children frequently developed viral ARI and a substantive proportion required hospital care. Such findings suggest the importance of exploring the value of new interventions and increasing uptake of existing prevention measures to mitigate burden of epidemic-prone respiratory viruses.

Funding

The study was supported by the Centers for Disease Control and Prevention.

Changes in hemodynamics, renal blood flow and urine output during continuous renal replacement therapies

Continuous renal replacement therapies (CRRT) affect hemodynamics and urine output. Some theories suggest a reduced renal blood flow as the cause of the decreased urine output, but the exact mechanisms remain unclear. A prospective experimental study was carried out in 32 piglets (2–3 months old) in order to compare the impact of CRRT on hemodynamics, renal perfusion, urine output and renal function in healthy animals and in those with non-oliguric acute kidney injury (AKI). CRRT was started according to our clinical protocol, with an initial blood flow of 20 ml/min, with 10 ml/min increases every minute until a goal flow of 5 ml/kg/min. Heart rate, blood pressure, central venous pressure, cardiac output, renal blood flow and urine output were registered at baseline and during the first 6 h of CRRT. Blood and urine samples were drawn at baseline and after 2 and 6 h of therapy. Blood pressure, cardiac index and urine output significantly decreased after starting CRRT in all piglets. Renal blood flow, however, steadily increased throughout the study. Cisplatin piglets had lower cardiac index, higher vascular resistance, lower renal blood flow and lower urine output than control piglets. Plasma levels of ADH and urine levels of aquaporin-2 were lower, whereas kidney injury biomarkers were higher in the cisplatin group of piglets. According to our findings, a reduced renal blood flow doesn’t seem to be the cause of the decrease in urine output after starting CRRT.

Evaluation of functionality of type II toxin-antitoxin systems of Clostridioides difficile R20291

Clostridioides difficile is a nosocomial, Gram-positive, strictly anaerobic, spore-forming pathogen capable of colonizing and proliferating in the human intestine. In bacteria, it has been shown that the Toxin-Antitoxin systems mediate the cellular response to external stress by initiating processes such as biofilm formation and programmed cell death. This work aims to evaluate the functionality of four type II TA modules of Clostridioides difficile R20291. We performed bioinformatic analysis to search for putative TA systems using the TADB platform. Then we performed a heterologous expression assay to evaluate the functionality of these systems. Our results showed that the MazEF and RelBE systems were functional, suggesting that their corresponding toxins possess an endoribonuclease activity. In conclusion, MazEF and RelBE systems of C. difficile R20291 are functional in a heterologous expression system.

Statement of the Spanish Society of Allergology and Clinical Immunology on Provocation Tests With Aspirin/Nonsteroidal Anti-inflammatory Drugs

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used throughout the world. They are frequently involved in hypersensitivity reactions, which range from local or mild reactions to systemic and severe reactions. Consequently, it is necessary to perform an exhaustive study of patients in order to make an accurate diagnosis, search for safe procedures in the case of severe reactions, and identify alternative treatment options. Various guidelines and protocols address the management of hypersensitivity to NSAIDs, although these vary widely from country to country. The Committees of Asthma, Rhinoconjunctivitis, and Drug Allergy of the Spanish Society of Allergy and Clinical Immunology (SEAIC) propose the present position statement on available options for provocation testing with aspirin/NSAIDs. This document is the fruit of an exhaustive review of current evidence and is based on recent publications addressing the diagnosis of patients with hypersensitivity to NSAIDs and on a consensus-oriented discussion among a group of experts from the SEAIC. The main objective was to draft an easy-toread, practical guideline for health care professionals in specialist areas who assess and manage patients with suspected hypersensitivity to NSAIDs. Furthermore, indications, contraindications, and procedures for oral, bronchial, and nasal provocation tests with aspirin/NSAIDs have been updated.

102 Sperm cryopreservation with a soy lecithin-based medium in black-footed cats (Felis nigripes) and sand cats (Felis margarita)

Felid semen has historically been frozen using an egg yolk-based cryopreservation medium (TEY). However, the use of egg introduces several potential concerns, such as variability in composition, microbial contamination, and regulatory issues. Our recent research has focused on developing an animal protein-free medium containing soy lecithin (SOY). Our studies revealed that SOY was superior to TEY for freezing domestic cat sperm and provided similar results for freezing ocelot, Pallas’ cat, and fishing cat sperm. The objective of this study was to compare SOY to the standard TEY for sperm cryopreservation in 2 wild cat species: the black-footed cat and sand cat. Semen was collected from adult male cats (n=6/species) via electroejaculation, split into 2 aliquots, centrifuged, resuspended in either SOY or TEY, slow-cooled, and frozen in straws over nitrogen vapor. Sperm motility [percent progressively motile (PPM); rate of progressive motility on 0-5 scale (RPM)] was evaluated at 0, 1, 3, 6, and 24h post-thaw and acrosome status (AC) was assessed at 0 and 6h post-thaw. Heterologous IVF was performed using oocytes collected laparoscopically from gonadotropin-treated domestic cats. At 48h post-insemination, Hoechst33342 staining was used to determine oocyte stage, number of blastomeres, and number of accessory sperm (AS) bound to the zona pellucida of embryos and mature oocytes. Percent progressively motile, RPM, and AC were analysed with repeated-measures ANOVA; embryo cleavage, blastomere number, and AS number were analysed with one-way ANOVA. All data are reported as least squares means±average standard error. In the black-footed cat, PPM, RPM, and AC of SOY-treated sperm (32.5±4.0% motile, 2.8±0.2 RPM, 41.8±4.1% intact; 0h) did not differ from TEY-treated sperm (44.2±4.0% motile, 2.8±0.2 RPM, 46.8±4.1% intact; 0h) at any post-thaw time point (P &gt; 0.05). Similarly, in the sand cat, post-thaw PPM, RPM, and AC of SOY-treated sperm (36.7±5.2% motile, 2.6±0.2 progression, 53.3±5.8% intact; 0h) did not differ from TEY-treated sperm (45.8±5.2% motile, 2.8±0.2 RPM, 51.0±5.8% intact; 0h) at any time point (P &gt; 0.05). In black-footed cats, neither embryo cleavage (34.1±10.9% SOY; 58.5±10.9% TEY), blastomere number (7.8±0.8 SOY; 6.3±0.8 TEY), nor AS (3.5±0.8 SOY; 1.7±0.8 TEY) differed between treatments (P &gt; 0.05). Sand cat results were similar, with no difference between SOY and TEY for cleavage (44.7±10.8% SOY; 40.6±10.8% TEY) or blastomere number (7.4±2.0 SOY; 6.7±2.0 TEY) (P &gt; 0.05), but AS was higher in SOY-treated sperm (4.3±0.2 SOY; 3.5±0.2 TEY, P=0.0183). These data collectively demonstrate that our SOY medium was an effective substitute to TEY for sperm cryopreservation in the black-footed cat and sand cat. The replacement of an egg yolk-based cryomedium with a chemically defined, animal protein-free alternative represents a significant advance in quality control and biosecurity for felid semen banking and should augment the use of assisted reproduction for population management of imperiled cats. Funded by the Institute of Museum and Library Services.

101 Assessment of semen traits in servals (Leptailurus serval) and Canada lynx (Lynx canadensis)

Servals and Canada lynx are managed by species survival plans in North American zoos, but current populations are not sustainable. Increased knowledge of their reproductive biology would benefit breeding management and development of assisted reproductive techniques. The aims of our study were to (1) evaluate effectiveness of urethral catheterization and electroejaculation (EEJ) for semen collection; (2) characterise basal seminal traits; and (3) compare effectiveness of semen cryopreservation methods. Semen was collected from 6 servals and 9 Canada lynx via a urinary catheter (3.5 Fr×22 cm, inserted 15cm into the urethra), followed by EEJ under dexmedetomidine-ketamine anaesthesia. To assess the effect of seasonality on lynx seminal traits, semen was collected before (late January), during (mid-February to mid-March), and after (early April) the peak breeding season. Serval and lynx semen were frozen by conventional slow freezing (i.e. in 0.25-mL straws cooled to 4°C for 2h and frozen in LN vapor) in a soy lecithin-based (SOY) or egg yolk-based (TEY) extender with 4% glycerol and by ultra-rapid freezing (URF; direct pelleting into LN at ≈104°C/min) in SOY medium with 0.2M sucrose. To evaluate post-thaw sperm function in servals, heterologous IVF of domestic cat oocytes was performed, with cleavage rate assessed at 48h post-insemination. Data were analysed by one-way or repeated-measures ANOVA. Data are mean±standard deviation. Sperm recovery by urethral catheterization was negligible in both species, but EEJ allowed sperm collection in all males. Lynx seminal traits were similar during breeding and nonbreeding seasons. Testicular volume (4.81±1.17cm3) and sperm quality (13±11×106 sperm/ejaculate; 49±14% motility; 29±12% normal morphology; 74±13% acrosome integrity) were consistent with previous findings in the lynx genus. Post-thaw sperm quality in lynx has not yet been evaluated. In servals, testes volume was 6.56±2.11cm3 with good sperm quality for most males (46±36×106 sperm/ejaculate; 75±20% motility; 56±36% normal morphology; 84±7% acrosome integrity). Post-thaw, serval sperm acrosome integrity (31±15, 21±13, 24±13% at 0h for TEY, SOY, and URF, respectively; P&gt;0.05) and motility (40±21% at 0h, 20±11% at 6h for TEY; 24±19% at 0h, 6±4% at 6h for SOY; 21±16% at 0h, 3±2% at 6h for URF; treatment: P&gt;0.05; time: P&lt;0.05; interaction: P&gt;0.05) declined substantially. However, thawed sperm could fertilize domestic cat oocytes with no difference among treatments in cleavage success (53±6, 47±4, or 49±14%; TEY, SOY, and URF, respectively; P&gt;0.05), indicating that standard freezing methods are effective in servals. Our findings provide zoos with valuable information about normative reproductive traits in both species. Supported by IMLS and the Roger &amp; Kathy Gross Post-doctoral Fellowship.

Clinical course and pathogenicity of variant rabbit haemorrhagic disease virus in experimentally infected adult and kit rabbits: Significance towards control and spread

RHDVb has become the dominant RHDV on the Iberian Peninsula. A better understanding of its pathogenicity is required to aid control measures. Thus, the clinical course, humoral immune response, viraemia and kinetics of RHDV-N11 (a Spanish RHDVb isolate) infection in different tissues at both viral RNA and protein levels were studied in experimentally infected young and adult rabbits. The case fatality rate differed between the two age groups, with 21% of kits succumbing while no deaths were observed in adults. Fever and viremia were strongly associated with death, which occurred 48 h post infection (PI) too fast for an effective humoral immune response to be mounted. A significant effect on the number of viral RNA copies with regard to the variables age, tissue and time PI (p < 0.0001 in all cases) was detected. Histological lesions in infected rabbits were consistently more frequent and severe in liver and spleen and additionally intestine in kits, these tissues containing the highest levels of viral RNA and protein. Although no adults showed lesions or virus antigen in intestine, both kits and adults maintained steady viral RNA levels from days 1 to 7 PI in this organ. Analysis revealed the fecal route as the main dissemination route of RHDV-N11. Subclinically infected rabbits had detectable viral RNA in their faeces for up to seven days and thus may play an important role spreading the virus. This study allows a better understanding of the transmission of this virus and improvement of the control strategies for this disease.

Neoplasms of Unknown Primary Site: A Clinicopathological Study of Autopsied Patients

Background

Malignant neoplasms of an unknown primary site (NUPS) remain a diagnostic and therapeutic challenge in clinical practice. With this in mind, we have reviewed all autopsies performed in patients with NUPS in a single institution.

Patients and methods

By reviewing 1656 autopsies performed on adults in our Institution (1974-1990), 43 cases of NUPS were found. (NUPS was defined as histologically proven malignant tumor for which a primary site could not be found after anamnesis, complete physical examination, chest X-ray and routine chemistries.)

Results

There were 24 men (56 %) and 19 women. Mean age was 62 years (76 % of patients were aged 40-75). Clinical presentation included general deterioration (73 %), digestive symptoms (58 %), liver enlargement (58 %) abdominal pain (56 %), respiratory symptoms (45 %), ascites (26 %) and node enlargement (16 %). Abnormalities in analysis and image tests were frequent but nonspecific. Median time from admission to death was 42 days (range, 4-135). Pathologic diagnoses at autopsy were: 23 adenocarcinomas (53 %), arising from pancreas (6), biliary tree (6), lung (3), prostate (2), stomach (1), kidney (1) and unknown (4); 3 squamous carcinomas (5 %) (1 renal pelvis, 1 biliary tree, 1 stomach); 5 undifferentiated carcinomas (1 lung, 4 unknown); and 12 miscellaneous tumors (including 3 lymphomas, 3 neuroendocrine tumors, 3 hepatocarcinomas, 2 mesotheliomas and 1 melanoma). There was a tendency towards a metastatic pattern different from that expected from the primary tumor. Image tests were of little usefulness in the search for the primary tumor.

Conclusions

1) Adenocarciomas were the most frequent tumor presenting as NUPS, especially from the pancreas and biliary tree. 2) In this series, at least 11 % of patients were amenable to standard systemic therapies (3 lymphomas and 2 prostatic adenocarcinomas) if a correct pathologic diagnosis could have been established when alive. 3) Presenting symptoms and metastatic pattern differed from those expected for the primary neoplasm eventually found. 4) Image tests were often misleading as regards the primary site, although they were useful to quantify the dissemination of the tumor.

Curve of Perceptive Intellectual Deterioration in Hemodialysis Patients

In order to optimize the results of kidney transplant, i.e. patient's acceptance and speedy recovery, the available organ resources must be combined with appropriate “preparation” of the patient's mental state. In order to plot the “mental deterioration curve” of patients on a hemodialysis program, the present study was made on 62 patients in a general hospital in Spain. The possible repercussions of treatment of kidney disease on intellectual (Weschler's Adult Intelligence Scale-WAIS test) and perceptive (Benton test) capacity were investigated. Samples were grouped according to whether they had been on dialysis for up to four years (<4) or more than four years (>4). The WAIS test for the >4 group indicated a lower I.Q. These results indicated that it was after four years on dialysis that greater negative effects began to be seen in perceptive-intellectual capacity. The Benton test indicated that time on hemodialysis adversely affected the patient's capacities. A sharp decline was seen particularly between two and four years in the <4 group, suggesting that patients’ mental conditions vary with time on dialysis but that their resources and capacities are still fairly untroubled by the treatment in the first two years. In the light of these findings, the deterioration curve should be taken into account when planning kidney transplant, in order to take advantage of the initial period if possible.

Analysing the natural population growth of a large marine mammal after a depletive harvest

An understanding of the underlying processes and comprehensive history of population growth after a harvest-driven depletion is necessary when assessing the long-term effectiveness of management and conservation strategies. The South American sea lion (SASL), Otaria flavescens, is the most conspicuous marine mammal along the South American coasts, where it has been heavily exploited. As a consequence of this exploitation, many of its populations were decimated during the early 20th century but currently show a clear recovery. The aim of this study was to assess SASL population recovery by applying a Bayesian state-space modelling framework. We were particularly interested in understanding how the population responds at low densities, how human-induced mortality interplays with natural mechanisms, and how density-dependence may regulate population growth. The observed population trajectory of SASL shows a non-linear relationship with density, recovering with a maximum increase rate of 0.055. However, 50 years after hunting cessation, the population still represents only 40% of its pre-exploitation abundance. Considering that the SASL population in this region represents approximately 72% of the species abundance within the Atlantic Ocean, the present analysis provides insights into the potential mechanisms regulating the dynamics of SASL populations across the global distributional range of the species.

Therapy with ombitasvir/paritaprevir/ritonavir plus dasabuvir is effective and safe for the treatment of genotypes 1 and 4 hepatitis C virus (HCV) infection in patients with severe renal impairment: A multicentre experience

Limited data are available on direct-acting antivirals for treating hepatitis C virus (HCV) infection in patients with severe renal impairment. The aim of this study was to evaluate the effectiveness and safety of ombitasvir/paritaprevir/ritonavir (OBV/PTV/r) ± dasabuvir (DSV) ± ribavirin (RBV) in patients with stage 4 or 5 chronic kidney disease (CKD) and HCV genotype 1 or 4 infection in real clinical practice, and to investigate pharmacological interactions. This retrospective study included patients treated with OBV/PTV/r+DSV±RBV or OBV/PTV/r+RBV with CKD stage 4 (eGFR: 15-29 mL/min/1.73m² ) or 5 (eGFR<15 mL/min/1.73m² or requiring dialysis) and HCV infection by genotypes 1 and 4 between April 2015 and October 2015 in nine Spanish centres. Sustained virological response at 12 weeks (SVR12) was assessed, and clinical and laboratory data, fibrosis stage, adverse events and pharmacological interactions were reported. Forty-six patients were included: 10 (21.7%) had CKD stage 4 and 36 (78.2%) CKD stage 5. Seventeen (36.9%) had cirrhosis. SVR12 rate in the intention-to-treat population was 95.7%. Twenty-one (45.6%) received RBV, which was discontinued in two (9.5%) patients. Anaemia (haemoglobin <10 g/dl) occurred in 12 patients (57.1%) with RBV vs 10 (40.0%) without RBV (P=.246). Renal function remained stable during antiviral therapy. Nine patients (19.5%) experienced serious adverse events unrelated to antiviral therapy. Concomitant medication was discontinued or modified in 41.3% of patients. In conclusion, the effectiveness of OBV/PTV/r±DSV±RBV in patients with CKD 4-5 was similar to that observed in those with normal renal function and was not associated with severe adverse events.

Tropical fish community does not recover 45 years after predator introduction

Predation is considered to be an important factor structuring natural communities. However, it is often difficult to determine how it may influence long-term, broad-scale, diversity patterns, particularly in diverse tropical systems. Biological introductions can provide powerful insight to test the sustained consequences of predation in natural communities, if pre-introduction data are available. Half a century ago, Zaret and Paine demonstrated strong and immediate community-level effects following the introduction of a novel apex predator (peacock bass, Cichla monoculus) into Lake Gatun, Panama. To test for long-term changes associated with this predator introduction, we followed up on their classic study by replicating historical sampling methods and examining changes in the littoral fish community at two sites in Lake Gatun 45 years post-introduction. To broaden our inference, we complemented this temporal comparison with a spatial analysis, wherein we compared the fish communities from two lakes with and one lake without peacock bass. Comparisons with historical data revealed that the peacock bass remains the most abundant predator in Lake Gatun. Furthermore, the collapse of the littoral prey community observed immediately following the invasion has been sustained over the past 45 years. The mean abundance of native littoral fish is now 96% lower than it was prior to the introduction. Diversity (rarefied species richness) declined by 64% post-introduction, and some native species appear to have been locally extirpated. We observed a similar pattern across invaded and uninvaded lakes: the mean abundance of native fishes was 5-40 times lower in lakes with (Gatun, Alajuela) relative to the lake without peacock bass (Bayano). In particular, small-bodied native fishes (Characidae, Peociliidae), which are common prey of the peacock bass, were more than two orders of magnitude (307 times) less abundant in Gatun and one order of magnitude (28 times) less abundant in Alajuela than in Bayano. However, total native fish diversity did not differ significantly across lakes, suggesting that while many native species have declined in abundance, few have been completely extirpated. Introduced predators can have strong effects on community structure and functional diversity, even in highly diverse tropical communities, and these effects can persist over multiple decades.

A route to small clusters: a twisted half-hexagram-shaped M4(OH)4 cluster and its capacity for hosting closed-shell metals

The secret to making a new M₄(OH)₄ core structure lies in combining different oxidation states, coordination geometries and bridging systems. The spatial distribution of Pt(ii) atoms in Pt₄(OH)₄ is capable of cradling incoming Ag(i) centers.

Modificación simplificada de la técnica de Zancolli para la corrección de la garra cubital

Objetivos: Estudiar los resultados obtenidos con la técnica de Chevallard, versión simplificada de la técnica de Zancolli, para corregir la deformidad de la mano en garra secundaria a una parálisis cubital.

Material y método: Estudio retrospectivo (enero 2006-diciembre 2013) de 16 pacientes (16 manos) que fueron intervenidos quirúrgicamente por deformidad en garra de la mano secundaria a parálisis del nervio cubital. Siguiendo los criterios de Brand, los pacientes fueron evaluados a las 6 semanas, 3 meses, 6 meses y al año.

Resultados: Los resultados al año de la intervención fueron: excelentes en el 18,75% (3 pacientes); buenos en el 75% (12 pacientes) y malos en el 6,25% (un paciente). Este último requirió una nueva intervención para solucionar la recidiva de la garra.

Conclusión: La técnica simplificada de Zancolli, o técnica de Chevallard, permite corregir fácilmente la deformidad de la mano en garra secundaria a una parálisis cubital, no hipotecando una ulterior intervención en el caso de recidiva.

Unilateral retinitis pigmentosa. A case report

CLINICAL CASE

A 27-year-old woman with a history of nyctalopia and constriction of visual field of the right eye. The ophthalmological examination showed a visual field and electroretinogram that were compatible with unilateral retinitis pigmentosa (RP). After a one year follow-up, the unilateral condition remained.

DISCUSSION

Unilateral retinitis pigmentosa is a rare condition, with a frequency between 0.2%-5% of the RP. It mainly affects women and older age groups than bilateral RP. For a definitive diagnosis, it is necessary to have a funduscopy and electroretinogram (ERG) altered unilaterally, and exclude infectious, inflammatory, and vascular causes.

Review: the Use of Electromyography on Food Texture Assessment

Sensory evaluation (SE) involves evoking, measuring and interpreting human responses to the properties of foods. Among these properties texture is an important one for food acceptability. Texture is mainly perceived through mastication, a process that changes food characteristics throughout time by comminuting and salivation. Electromyography (EMG) has emerged as a new tool in sensory evaluation mainly for assessing texture characteristics. Thus, it is interesting to analyze the knowledge so far generated and the procedures employed. Bipolar surface electrodes are placed on the four main masticatory muscles (masseter right-left and temporalis right-left) and their electric activity recorded during mastication. The signals need to be amplified and filtered, and afterwards their acquisition by a computer allows conditioning and analysis. The output is a series of bursts corresponding to the chews during mastication. EMG parameters include the area under the curve (linked to masticatory work) and voltage (linked to the force exerted) at different moments of the process. Many other parameters are derived from the recording and related to food texture characteristics. EMG allows the study of changes throughout the masticatory process, these changes in EMG parameters permit a better assessment of sensory characteristics than mechanical measurements. Nevertheless, close-fitting correlations have been found between sensorymechanical-EMG measurements. In the literature, texture assessment by using EMG includes many products like carrots, biscuits, cooked meat, cooked rice, cheese, etc., as well as different texture characteristics like tenderness, hardness, crunchiness, juiciness, among others. Nowadays, texture studies involving EMG are mainly linked to describing changes or differences in the signals, good descriptors of perceived differences. Nevertheless for quantifying purposes, in order to allow comparisons among authors, a first step should be undertaken to standardize EMG parameters definition and procedures used in SE.