A diet based on cured acorn-fed ham with oleic acid content promotes anti-inflammatory gut microbiota and prevents ulcerative colitis in an animal model

Background

Diets based on meat products are not recommended in the case of ulcerative colitis (UC). The objective here is to test if some traditional cured meat products, as acorn-fed ham (high levels of oleic acid), may be useful for controlling inflammatory diseases as UC in animal models, which could represent a new dietary complementary intervention in the prevention of this inflammatory disease in humans.

Methods

Two rat cohorts have been used: conventional vegetable rat feed and acorn-fed ham. UC was induced with DSS in drinking water ad libitum for 1 week. Short-chain fatty acids (SCFAs) and 16S rRNA metagenomics from bacterial populations were analyzed in cecum samples. Colon samples were analyzed for histological parameters.

Results

Acorn-fed ham diet induced changes in gut microbiota composition, with pronounced enrichments in anti-inflammatory bacterial genera (Alistipes, Blautia, Dorea, Parabacteroides). The animals with this diet showed a strong reduction in most parameters associated to ulcerative colitis: disease activity index, macroscopic score of colitis, epitelium alteration in colon mucosa, inflammatory cell density in colon, myeloperoxidase titers in colon, proinflammatory cytokines (IL-17, IFN-γ). Also, acorn-fed ham diet animals showed increased total antioxidant activity an oleic acid levels in plasma, as well as higher short-chain fatty acid concentrations in cecum (isobutyric, isovaleric and valeric).

Conclusions

In the acorn-fed ham cohort, as a result of the dietary intake of oleic acid and low intake of omega-6 fatty acids, a strong preventive effect against UC symptoms was observed.

[Genetic characterization of Listeria monocytogenes strains isolated during 2007-2014 in Chile]

BACKGROUND

Listeria monocytogenes is a foodborne pathogen that causes listeriosis, a disease that can present as febrile gastroenteritis or as an invasive form that has high mortality rates. So far, the genetic diversity of strains of L. monocytogenes isolated from patients, foods and environmental sources in Chile has been poorly studied.

AIM

To characterize genetically L. monocytogenes strains received by the Institute of Public Health of Chile (ISP) between 2007 and 2014.

METHODS

We selected 94 strains of L. monocytogenes corresponding to 94 different pulsotypes identified by pulsed field gel electrophoresis (PFGE), DNA was extracted and serotyping was performed by polymerase chain reaction (PCR) and multilocus sequence typing (MLST).

RESULTS

The most common serotype was 4b (55.3%), followed by serotypes 1/2a (25.5%), 1/2b (17%) and 1/2c (2.2%). 32 sequence-type (ST) were identified, of which 4 were new, and the predominant ones were ST1 (28.7%) and ST2 (13.8%). All the strains of L. monocytogenes were grouped in Lineages I and II.

CONCLUSIONS

A great genetic variability was observed in the strains of L. monocytogenes analyzed, being predominant the ST1 and ST2, both belonging to Lineage I. Our results contribute to know the population structure of this pathogen in Chile and its presence in clinical samples, food and the environment.

Prospective multicentre study of rectal carriage of multidrug-resistant Enterobacteriaceae among health-care workers in Spain

OBJECTIVES

To investigate the rectal carriage of multidrug-resistant Enterobacteriaceae (colistin-resistant, extended-spectrum β-lactamase (ESBL) -producers and/or carbapenemase-producers) among health-care workers (HCWs) from six Spanish hospitals.

METHODS

Rectal swabs from 258 HCWs, employed in intensive care units, haematology wards and clinical microbiology laboratories from six hospitals in northern Spain were studied. They were cultured in selective media for Gram-negative resistant bacteria. Detection of antimicrobial resistance genes and multilocus sequence typing were performed by PCR and further sequencing. A questionnaire including data related to risk factors of colonization/infection by resistant bacteria (age, gender, chronic diseases, immunosuppressive therapies, invasive procedures or antimicrobial treatments) was given to each participant.

RESULTS

No carbapenemase-producing Enterobacteriaceae were recovered. However, 8/258 HCWs (3.1%) were positive for ESBL-producing isolates. This rate was not higher than the colonization rate previously reported in Spain for healthy people in the community. Five isolates showed high-level resistance to colistin (MICs ranging from 8 to 128 mg/L) but all of them were negative for the mcr genes tested. No statistically significant risk factors for gut colonization by ESBL-producing or colistin-resistant Enterobacteriaceae were identified among the HCWs participating in the study.

CONCLUSIONS

Our data suggest that working in hospitals does not represent a risk for rectal carriage of multidrug-resistant Enterobacteriaceae.

Vibroequilibria in microgravity: Comparison of experiments and theory

Experiments on vibrated fluids confined in cylindrical and cuboidal containers were performed under the reduced gravity conditions of a parabolic flight. The results constitute a systematic quantitative investigation of the vibroequilibria effect, which refers to the reorientation of vibrated fluids in response to the inhomogeneous oscillatory velocity field and the accompanying dynamic pressure. This effect is amplified in microgravity where the restoring force of gravity is small or absent. Here the vibrations are transmitted via a pair of piezoelectric ceramics and a cantilever beam, excited in a resonant mode. The first and second resonances exhibit different types of motion and lead to different types of vibroequilibria surfaces, one with a dip or crater in the interior and the other flattened compared to the unforced reference experiment. The general tendency for interfaces to orient more perpendicular, on average, to the vibrational axis is confirmed. In the case of water in a cuboidal container, a quantitative comparison is made with vibroequilibria theory and with direct simulations of the Navier-Stokes equations. The good agreement confirms the predictions of vibroequilibria theory and suggests the capacity of this phenomenon to manipulate and position fluids in space environments through the choice of frequency and resonant mode.

Long-term endemic situation caused by a linezolid- and meticillin-resistant clone of Staphylococcus epidermidis in a tertiary hospital

BACKGROUND

Linezolid (LZD)-resistant Staphylococcus epidermidis (LRSE) are increasing, and are mainly associated with outbreaks in hospital wards with high LZD consumption.

AIM

To investigate the frequency of LRSE in a tertiary hospital in the context of LZD use.

METHODS

The frequency of LRSE and the data on LZD usage [expressed as defined daily dose (DDD) per 100 patient-days], from 2011 to 2017, were analysed retrospectively. Selected LRSE were typed by pulsed-field gel electrophoresis (PFGE) and screened for transferable LZD resistance genes. Representative isolates were typed by multi-locus sequence typing, and ribosomal mechanisms of LZD resistance were investigated.

FINDINGS

In total, 435 LRSE were detected, with frequencies ranging from 13.56% to 32.93% in the intensive care unit (ICU) where LZD consumption was high (6.34-8.10 DDDs), and from 2.48 to 6.80% in the remaining wards where LZD use was considerably lower (0.63-2.49 DDDs). The first 44 LRSE isolates recovered (June 2013-June 2014) were closely related according to PFGE patterns, and all except one were resistant to meticillin due to mecA production. Selected isolates belonged to ST2, carried SCCmec III, and had the G2576T mutation in the V domain of each of the six copies of the 23S rRNA gene. Five of the 44 isolates (11.36%) were positive for the cfr gene.

CONCLUSION

An ST2 LZD- and meticillin-resistant clone was found in the ICU and also in wards with low consumption of LZD. This highlights the need to implement and maintain infection control measures as well as antimicrobial stewardship programmes in all hospital units in order to preserve the efficacy of LZD.

Tunable upconversion emission in NaLuF4-glass-ceramic fibers doped with Er3+ and Yb3

Novel glass-ceramic optical fibers containing NaLuF₄ nanocrystals doped with 0.5ErF₃ and 2YbF₃ (mol%) have been prepared by the rod-in-tube method and controlled crystallization. NaLuF₄ nanocrystals with a size around 20 nm are obtained after heat treatment at 600 °C. Intense upconverted green and red emissions due to (²H_11/2, ⁴S_3/2) → ⁴I_15/2 and ⁴F_9/2 → ⁴I_15/2 transitions, respectively, together with a blue emission due to ²H_9/2 → ⁴I_15/2 transition have been observed under excitation at 980 nm. The intensity of the green and red upconversion bands shows a nearly linear dependence on the excitation power which can be explained by saturation effects in the intermediate energy states and proves that a sensitized energy transfer upconversion process is responsible for the population of the emitting levels of Er³⁺ ions. The upconversion emission color changes from yellow to green by increasing the excitation power density which allows to manipulate the color output of the Er³⁺ emission in the glass-ceramic fibers. The tunable emission color is easily detected with the naked eye. This interesting characteristic makes these glass-ceramic fibers promising materials for photonic applications.

Novel glass-ceramic optical fibers containing NaLuF₄ nanocrystals doped with 0.5ErF₃ and 2YbF₃ (mol%) have been prepared by the rod-in-tube method and controlled crystallization.

[Outbreak of fungemias by Sarocladium kiliense in eight public hospitals per intrinsic contamination of ondansetron intravenous]

Sarocladium kiliense is a saprophyte fungus that can cause opportunistic infections associated to invasive procedures. We report a multi-hospital nosocomial outbreak of fungemias due to this agent. Patients with positive blood culture to this agent were studied after six bloodstream infections identified in three Chilean hospitals in July 2013 were reported to Ministry of Health National Infection and Prevention Control Program. In general, there were mild clinical manifestations, without deaths attributable to the infection. Epidemiological and micro-biological study identified 65 cases in 8 hospitals, mostly pediatric patients in chemotherapy. Initial studies of 94 different drugs and medical devices had negative results, until a second analysis of specific blisters and their pharmaceutical matrix selected by epidemiological criteria identified an intrinsic contamination of ondansetron blisters from a specific producer used in all the patients. A recall of contaminated ondansetron blisters was performed in all the country, after which the outbreak was contained. Surveillance and response of local and national infection prevention and control programs and laboratory support were key to control of a national multi-hospital common source outbreak due to contamination of a drug by an unusual fungus.

Input/output energy in solid state dye random lasers

A new approach to the problem of energy in solid state dye random lasers is presented. The measurements performed in terms of absolute energy show that the slope efficiency depends on the measurement conditions. In particular, in lasers with pumping in the picoseconds range, the result is really different if measured by recording the emission in the same time range or in a longer one (nanoseconds range). In the last case, no energy threshold is observed. A previously developed model has been applied to the solid state dye random laser. It is a rate-equations model, based on a distribution of paths with different lengths, which partially share population inversion. The results of the model are satisfactory and show that the dynamic behavior is pretty similar in solid state dye random lasers and in inorganic powders.

Organochlorine pesticides air monitoring near a historical lindane production site in Spain

The landfilling and dumping of persistent organic pollutants (POPs) and other persistent hazardous chemicals, such as hexachlorocyclohexane (HCH) isomers can have significantly adverse environmental consequences and cause contamination in soil, water, and atmosphere systems. Approximately 115,000 t of HCH wastes were generated by INQUINOSA Factory located in Sabiñánigo (Aragón, Spain) from 1975 to 1992, and were mainly dumped at Bailín and Sardas landfills. Under the frame of the project plan approved by the Government of Aragón, remediation and containment measures were implemented at the derelict production facility and landfill sites. To protect and assess the local environment, the concentrations of HCH isomers, pentachlorobenzene (PeCB) and hexachlorobenzene (HCB) in air were periodically monitored in the Sardas landfills and surroundings by passive sampling devices. The influence of meteorological parameters was evaluated, showing positive correlations between temperature and HCH and HCB concentrations. The highest HCH levels were detected in Sardas landfill and INQUINOSA Factory sites. PeCB values were statistically higher in Sardas landfill than in Sabiñánigo urban core, nevertheless, HCB concentrations were similar in both sampling points. Statistically positive correlations were found among HCH isomers in all sampling points, showing a major common source. The chlorobenzenes also correlated positively with each other. The α-/γ-HCH ratios were calculated (1.46 ± 1.25; mean ± S.D.), corroborating that concentrations detected were mainly originated from the historical production, storage and waste disposal of technical HCH.

Genetic variability of human papillomavirus type 66 L1 gene among women presenting for cervical cancer screening in Chile

The high-risk human papillomaviruses (HR-HPVs) are involved in the development of cervical cancer. Nevertheless, there are differences in the oncogenic potential among them. HPV-16 and HPV-18 are associated with approximately 70% of cancer worldwide, and both types are the most extensively studied HR-HPV. Great variations in the prevalence of HR-HPV have been described in different countries. The impact of these variations on the epidemiology of lesions and cervical cancer is currently unknown. A high prevalence of HPV-66 has been detected in Chile. Here, we have analyzed the genetic variability of the L1 gene from HPV-66-infected Chilean women. Higher order interactions between identified mutations were analyzed by co-variation and cluster analyses. Antigenic-index alterations following L1 mutations and B-cell epitopes were predicted by BcePred algorithm. HPV-66 L1 sequences clustered phylogenetically into two main clades. The genetic variability in the HPV-66 L1 gene involved thirty nucleotide changes. Four of these were for the first time identified in this study. Some of these variants are embedded in the B-cell epitope regions. Amino acid homology in the immunodominant epitopes of HPV-66 L1 protein (DE, FG and H1 loops) was 42.9-59.1% and 28.6-68.9% compared with HPV-16 and HPV-18, respectively. The results of this research suggest that the neutralizing epitopes of HPV-66 are antigenically different compared to HPV-16 and HPV-18. Our findings show the need to perform new structural and immunological studies on HPV-66 L1 protein to evaluate the cross-protection conferred by current HPV vaccines.

Investigating the Role of Easter Island in Migration of Zika Virus from South Pacific to Americas

The role of Easter Island in the dissemination of Zika virus from the Pacific islands into the Americas remains unclear. We analyzed new Zika virus sequences from Eastern Island and found that Zika virus was independently disseminated from French Polynesia into the Americas and Easter Island at around the same time.

Nuevos táxones animales descritos en la península Ibérica y Macaronesia desde 1994 (XXI)

La lista anual incluye en esta ocasión 580 táxones nuevos aparecidos en 309 referencias bibliográficas publicadas principalmente en 2017 y 2018. Comprende 463 especies, 69 géneros o subgéneros, 35 categorías supragenéricas, 12 subespecies y una categoría infrasubespecífica procedentes del área considerada.

Epidemiologic and Histopathologic Characterization of Cutaneous Metastases in Patients Who Visited 2 Hospitals in Santiago de Chile Between 2005 and 2017

BACKGROUND AND OBJECTIVE

Cutaneous metastases (CMs) account for 2% of skin tumors and their incidence varies between 0.7% and 9% in patients with cancer. The objective of this study was to describe and analyze the demographic, clinical, and histopathologic characteristics of CM in patients who visited 2 hospitals in the Santiago de Chile metropolitan region.

MATERIAL AND METHOD

We performed a retrospective, descriptive, analytical, observational, cross-sectional study. We reviewed the pathology reports, patient records, pathology slides, and dates of death for diagnosed cases of CM from the anatomic pathology departments of 2 hospitals in the Santiago de Chile metropolitan region between 2015 and 2017.

RESULTS

Ninety-six patients with CM were included in the study; 60.42% were women and 39.58% were men. The mean (SD) age was 67.95 (13.74) years, with a range of 28 to 96 years. The most common primary tumor was melanoma in 27.08% of cases (n=26), followed by breast cancer (18.75%, n=18), and adenocarcinoma (15.63%, n=15). The median time between diagnosis of the tumor and cutaneous metastasis was 9 months. Patients with CM of melanoma had a higher survival rate than patients with metastasis of other primary tumors (P<.05). A histopathologic study of 91 slides showed that diffuse infiltration of the tissue with tumor cells was the most common pattern and vascular invasion was rare.

CONCLUSIONS

The results are similar to those found worldwide. CM is a rare manifestation of internal tumors. It presents mainly at an advanced age and is equally prevalent in both sexes.

Random laser model for Nd3+-doped powders and its application to stimulated emission cross-section calculations

A new theoretical approach for random lasing of Nd³⁺doped powders is presented. The model's singularity lies in the fact that it proposes a probability distribution of the stimulated photon paths lengths in the sample, as well as a population inversion shared by different photon paths. The model's predictions satisfactorily compare with the results of laser threshold and absolute input/output energy slope of a real Random Laser. The main novel issue is that the best fit to the experimental results requires considering a high level of shared population inversion among different paths. The model simulation of local and spatially integrated Random Laser emissions, as well as their time evolution, is in accordance with the experimental behavior. These results also provide a new method of measuring the stimulated emission cross-section in this kind of random laser materials.

Chlorinated organic compounds in liquid wastes (DNAPL) from lindane production dumped in landfills in Sabiñanigo (Spain)

α, β and γ-hexachlorocyclohexane (HCH) are persistent and bioaccumulative pollutants and they were included in the Stockholm Convention on Persistent Organic Pollutants (POPs). Old lindane factories generated high amounts of wastes with HCH and other Chlorinated Organic Compounds (COCS). These were often dumped in the surroundings of the production sites, polluting soil and groundwaters with the associated risk of surface pollution. This is the case of the Sardas and Bailin landfills, located in Sabiñánigo (Huesca, Spain). Among the waste from lindane production, a liquid residue was detected in the landfill subsurfaces, forming a dense non-aqueous phase liquid (DNAPL) composed of HCH isomers, benzene and chlorobenzenes, with a high impact on groundwater pollution. In this study, six DNAPL samples obtained from the Bailin and Sardas landfills were analyzed by GC/MSD and GC/FID/ECD. Compounds were identified using mass spectra and the retention index from pure standards and literature information. Pure positional isomers of dichlorobenzene (DCB), trichlorobenzene (TCB), tetrachlorobenzene (TetraCB), HCH and pentachlorocyclohexene (PentaCX) were distinguished and quantified. In addition, heptachlorocyclohexane (HeptaCH) isomers, precursors of hexacholorocylohexene (HexaCX), were also identified and quantified in the DNAPL samples, although the corresponding isomers could not be discriminated. Information about PentaCX, HexaCx and HeptaCH identification is very limited in the literature. HCH contents in the DNAPL ranged from 22% to 30% in weight, the major isomers being lindane and δ-HCH, followed by α-HCH. The β isomer was the least abundant. HeptaCH contents were present in the same order of magnitude as HCHs in the DNAPL. PentaCXs and HexaCXs could have appeared as dehydrochlorination derivatives of HCHs and HeptaCHs, respectively. Two of the DNAPLs analyzed showed a higher content of TCBs and TetraCBs, associated with lower HCH and HeptaCH contents. Variations of these compounds in the DNAPL could be related to an alkaline dehydrochlorination in the landfill conditions.

Two-stage three-channel Kondo physics for an FePc molecule on the Au(1 1 1) surface

We study an impurity Anderson model to describe an iron phthalocyanine (FePc) molecule on Au(1 1 1), motivated by previous results of scanning tunneling spectroscopy (STS) and theoretical studies. The model hybridizes a spin doublet consisting in one hole at the [Formula: see text] orbital of iron and two degenerate doublets corresponding to one hole either in the 3d _xz or in the 3d _yz orbital (called π orbitals) with two degenerate Hund-rule triplets with one hole in the 3d _z orbital and another one in a π orbital. We solve the model using a slave-boson mean-field approximation (SBMFA). For reasonable parameters we can describe very well the observed STS spectrum between sample bias  -60 mV to 20 mV. For these parameters the Kondo effect takes place in two stages, with different energy scales [Formula: see text] corresponding to the Kondo temperatures related with the hopping of the z ² and π orbitals respectively. There is a strong interference between the different channels and the Kondo temperatures, particularly the lowest one is strongly reduced compared with the value in the absence of the competing channel.

Milk yield did not decrease in large herds of high-producing Holstein cows in semi-arid climate of Mexico

This study aimed to determine the trends in milk production, fertility, temperature-humidity index (THI), and herd size in dairy herds from the Laguna region in northern Mexico. Records of 16 dairy herds of Holstein cows from January 2002 to December 2016 were used. Milk production was categorized in low and high levels. Milk production and fertility were analyzed using generalized equation estimation procedures by a model of repeated measures that included the effect of year, month, and productive level, an interaction for month × productive level, and herd effect was nested in productive level. For THI, a generalized linear model that included the effects of year and month was used. Dairy herds with high levels of milk production yielded more milk than those with low levels (P < 0.001). Milk production in 2002 and 2016 was 27.4 ± 0.6 and 32.3 ± 0.7 L/cow/day, respectively. Fertility fluctuated throughout the study. Dairy herds with high levels of milk production recorded higher fertility than those with low levels (P < 0.001). From October to April, THI was < 70, whereas it was > 73 from May to September, indicating that cows were in heat stress (20 h/day). The median herd size was 995 and 2569 cows in 2002 and 2016, respectively. In conclusion, in large herds, milk production increased over the years of study, whereas fertility showed a wave cycle; nonetheless, when THI was > 73, both milk production and fertility decreased.