Invariant representations in deep learning for optoacoustic imaging

Image reconstruction in optoacoustic tomography (OAT) is a trending learning task highly dependent on measured physical magnitudes present at sensing time. A large number of different settings and also the presence of uncertainties or partial knowledge of parameters can lead to reconstruction algorithms that are specifically tailored and designed to a particular configuration, which could not be the one that will ultimately be faced in a final practical situation. Being able to learn reconstruction algorithms that are robust to different environments (e.g., the different OAT image reconstruction settings) or invariant to such environments is highly valuable because it allows us to focus on what truly matters for the application at hand and discard what are considered spurious features. In this work, we explore the use of deep learning algorithms based on learning invariant and robust representations for the OAT inverse problem. In particular, we consider the application of the ANDMask scheme due to its easy adaptation to the OAT problem. Numerical experiments are conducted showing that when out-of-distribution generalization (against variations in parameters such as the location of the sensors) is imposed, there is no degradation of the performance and, in some cases, it is even possible to achieve improvements with respect to standard deep learning approaches where invariance robustness is not explicitly considered.

m.3685T>C is a Novel Mitochondrial DNA Variant That Causes Leigh Syndrome

Variants in the mitochondrial genome can result in dysfunction of Complex I within the electron transport chain, thus causing disruptions in oxidative phosphorylation. Pathogenic variants in the MT-ND1 (NADH:ubiquinone oxidoreductase core subunit 1) gene that result in Complex I dysfunction are a known cause of Leigh syndrome. The patient is a 4-yr-old female who initially presented with generalized tonic–clonic seizures, with other symptoms of Leigh syndrome becoming apparent after the seizures. A three-generation pedigree revealed no family history of mitochondrial disorders. Laboratory studies were remarkable for elevated blood lactate, alanine, and GDF15. T₂-weighted magnetic resonance imaging (MRI) revealed bilateral asymmetric signal hyperintensities in the basal ganglia, specifically in the bilateral putamen and right caudate. Magnetic resonance spectroscopy showed regionally elevated glucose and lactate. Mitochondrial respiratory chain enzyme analysis on skin fibroblasts demonstrated slightly reduced Complex I function. A 16-gene dystonia panel and chromosomal microarray analysis did not identify any disease-causing variants. Combined exome and mitochondrial genome sequencing identified the m.3685T > C (MT-ND1 p.Tyr127His) variant with 62.3% heteroplasmy with no alternative cause for the patient's condition. Mitochondrial genome sequencing of the mother demonstrated that the m.3685T > C variant occurred de novo. The m.3685T > C variant is absent from population databases. The tyrosine 127 residue is highly conserved, and several nearby pathogenic variants in the MT-ND1 gene have been previously associated with Leigh syndrome. We propose that the m.3685T > C variant is a novel mitochondrial DNA variant that causes Leigh syndrome, and we classify this variant as likely pathogenic based on currently available information.

Biochemical Studies in Fibroblasts to Interpret Variants of Unknown Significance in the ABCD1 Gene

Due to newborn screening for X-linked adrenoleukodystrophy (ALD), and the use of exome sequencing in clinical practice, the detection of variants of unknown significance (VUS) in the ABCD1 gene is increasing. In these cases, functional tests in fibroblasts may help to classify a variant as (likely) benign or pathogenic. We sought to establish reference ranges for these tests in ALD patients and control subjects with the aim of helping to determine the pathogenicity of VUS in ABCD1. Fibroblasts from 36 male patients with confirmed ALD, 26 healthy control subjects and 17 individuals without a family history of ALD, all with an uncertain clinical diagnosis and a VUS identified in ABCD1, were included. We performed a combination of tests: (i) a test for very-long-chain fatty acids (VLCFA) levels, (ii) a D₃-C22:0 loading test to study the VLCFA metabolism and (iii) immunoblotting for ALD protein. All ALD patient fibroblasts had elevated VLCFA levels and a reduced peroxisomal ß-oxidation capacity (as measured by the D₃-C16:0/D₃-C22:0 ratio in the D₃-C22:0 loading test) compared to the control subjects. Of the VUS cases, the VLCFA metabolism was not significantly impaired (most test results were within the reference range) in 6/17, the VLCFA metabolism was significantly impaired (most test results were within/near the ALD range) in 9/17 and a definite conclusion could not be drawn in 2/17 of the cases. Biochemical studies in fibroblasts provided clearly defined reference and disease ranges for the VLCFA metabolism. In 15/17 (88%) VUS we were able to classify the variant as being likely benign or pathogenic. This is of great clinical importance as new variants will be detected.

Diagnostic performance of transvaginal ultrasound and magnetic resonance imaging for preoperative evaluation of low-grade endometrioid endometrial carcinoma: prospective comparative study

OBJECTIVE

To compare the diagnostic performance of transvaginal ultrasound (TVS) and magnetic resonance imaging (MRI) in the prediction of deep myometrial invasion (DMI) and cervical stromal invasion (CSI) in patients with low-grade (Grade 1 or 2) endometrioid endometrial cancer (EEC).

METHODS

This was a prospective study including all patients with low-grade EEC diagnosed between October 2013 and July 2018 at the Vall d'Hebron Hospital in Barcelona, Spain. Preoperative staging was performed using TVS and MRI, followed by surgical staging. Final histology was considered as the reference standard. Sensitivity, specificity, likelihood ratios and diagnostic accuracy were calculated for both imaging techniques in the prediction of DMI and CSI, and the agreement index was calculated for both techniques. The STARD 2015 guidelines were followed.

RESULTS

A total of 131 patients with low-grade EEC were included consecutively. Sensitivity was higher for TVS than for MRI both for the prediction of DMI (69% (95% CI, 53-82%) vs 51% (95% CI, 36-66%), respectively) and CSI (43% (95% CI, 27-61%) vs 24% (95% CI, 12-41%), respectively). Specificity was similar for TVS and MRI in the prediction of DMI (87% (95% CI, 78-93%) vs 91% (95% CI, 82-96%)) and equal in the prediction of CSI (97% (95% CI, 91-99%) for both). The agreement index between TVS and MRI was 0.84 (95% CI, 0.76-0.90) for DMI and 0.92 (95% CI, 0.85-0.96) for CSI.

CONCLUSIONS

The diagnostic performance of TVS is similar to that of MRI for the prediction of DMI and CSI in low-grade EEC, and TVS can play a role as a first-line imaging technique in the preoperative evaluation of low-grade EEC. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

High copper concentration reduces biofilm formation in Acidithiobacillus ferrooxidans by decreasing production of extracellular polymeric substances and its adherence to elemental sulfur

Acidithiobacillus ferrooxidans is an acidophilic bacterium able to grow in environments with high concentrations of metals. It is a chemolithoautotroph able to form biofilms on the surface of solid minerals to obtain its energy. The response of both planktonic and sessile cells of A. ferrooxidans ATCC 23270 grown in elemental sulfur and adapted to high copper concentration was analyzed by quantitative proteomics. It was found that 137 proteins varied their abundance when comparing both lifestyles. Copper effllux proteins, some subunits of the ATP synthase complex, porins, and proteins involved in cell wall modification increased their abundance in copper-adapted sessile lifestyle cells. On the other hand, planktonic copper-adapted cells showed increased levels of proteins such as: cupreredoxins involved in copper cell sequestration, some proteins related to sulfur metabolism, those involved in biosynthesis and transport of lipopolysaccharides, and in assembly of type IV pili. During copper adaptation a decreased formation of biofilms was measured as determined by epifluorescence microscopy. This was apparently due not only to a diminished number of sessile cells but also to their exopolysaccharides production. This is the first study showing that copper, a prevalent metal in biomining environments causes dispersion of A. ferrooxidans biofilms. SIGNIFICANCE: Copper is a metal frequently found in high concentrations at mining environments inhabitated by acidophilic microorganisms. Copper resistance determinants of A. ferrooxidans have been previously studied in planktonic cells. Although biofilms are recurrent in these types of environments, the effect of copper on their formation has not been studied so far. The results obtained indicate that high concentrations of copper reduce the capacity of A. ferrooxidans ATCC 23270 to form biofilms on sulfur. These findings may be relevant to consider for a bacterium widely used in copper bioleaching processes.

Unraveling the effects on lithium-ion cathode performance by cation doping M-Li2CuO2 solid solution samples (M = Mn, Fe and Ni)

Cation doping is one of the most dynamic strategies to enhance the electrochemical properties of cathode materials for lithium-ion batteries. Nevertheless, the maximum partial substitution capacity depends on the solubility of each metal ion, and so the formation of impurities is a very common consequence. Thus, the correlation between electrochemical performance and the doping effect is frequently unknown. In this study, the effect of the partial substitution of copper by manganese, iron or nickel in Li2CuO2 is evaluated, as well as the effect on the electrochemical performance of the modified Li2CuO2 samples as lithium ion battery cathode materials. XRD characterization confirmed single phase formation for all samples, and the incorporation of the transition metal in the Li2CuO2 structure was evaluated by XRD profile fitting, EPR and 7Li-NMR. The results showed modifications in intra- and inter-chain interactions, associated with the variations in the Cu-O-Cu bond angle and changes in magnetic order, due to the presence of the doping transition metal. Among all samples, only manganese partial substitution reveals a drastic improvement in the electrochemical stability during the charge/discharge processes even at potentials higher than 3.9 V. It was corroborated that the higher stability is attributed to (i) the increase in the superexchange interactions between the copper sites and manganese, directly modifying lithium diffusivity and electronic conductivity, both inferred from dynamic thermogravimetric analysis for CO2 sorption and conductivity tests, respectively and (ii) the lower propensity to enable O2 evolution during several charge cycles. These results are totally attributed to manganese cation partial substitution, which has a huge impact on the utilization of copper-based materials in real applications.

Bone density, microarchitecture, and material strength in chronic kidney disease patients at the time of kidney transplantation

Bone health is assessed by bone mineral density (BMD). Other techniques such as trabecular bone score and microindentation could improve the risk of fracture's estimation. Our chronic kidney disease (CKD) patients presented worse bone health (density, microarchitecture, mechanical properties) than controls. More than BMD should be done to evaluate patients at risk of fracture.

INTRODUCTION

BMD measured by dual-energy X-ray absorptiometry (DXA) is used to assess bone health in end-stage renal disease (ESRD) patients. Recently, trabecular bone score (TBS) and microindentation that can measure microarchitectural and mechanical properties of bone have demonstrated better correlation with fractures than DXA in different populations. We aimed to characterize bone health (BMD, TBS, and strength) and calcium/phosphate metabolism in a cohort of 53 ESRD patients undergoing kidney transplantation (KT) and 94 controls with normal renal function.

METHODS

Laboratory workout, lumbar spine/hip BMD measurements (using DXA), lumbar spine TBS, and bone strength were carried out. The latter was assessed with an impact microindentation device, standardized as percentage of a reference value, and expressed as bone material strength index (BMSi) units. Multivariable linear regression was used to study differences between cases and controls adjusted by age, gender, and body mass index.

RESULTS

Among cases, serum calcium was 9.6 ± 0.7 mg/dl, phosphorus 4.4 ± 1.2 mg/dl, and intact parathyroid hormone 214 pg/ml [102-390]. Fourteen patients (26.4%) had prevalent asymptomatic fractures in spinal X-ray. BMD was significantly lower among ESRD patients compared to controls: lumbar 0.966 ± 0.15 vs 0.982 ± 0.15 (adjusted p = 0.037), total hip 0.852 ± 0.15 vs 0.902 ± 0.13 (adjusted p < 0.001), and femoral neck 0.733 ± 0.15 vs 0.775 ± 0.12 (adjusted p < 0.001), as were TBS (1.20 [1.11-1.30] vs 1.31 [1.19-1.43] (adjusted p < 0.001)) and BMSi (79 [71.8-84.2] vs 82. [77.5-88.9] (adjusted p = 0.005)).

CONCLUSIONS

ESRD patients undergoing transplant surgery have damaged bone health parameters (density, microarchitecture, and mechanical properties) despite acceptably controlled hyperparathyroidism. Detecting these abnormalities may assist in identifying patients at high risk of post-transplantation fractures.

Fluorescence spectroscopy and parallel factor analysis as a dissolved organic monitoring tool to assess treatment performance in drinking water trains

Fluorescence excitation emission matrix (FEEM) spectroscopy was used to evaluate its applicability as a tool to track dissolved organic matter (DOM) in a drinking water treatment plant (DWTP) that incorporates a conventional line (consisting in ozonation and GAC filtration) and a membrane-based line (consisting in ultrafiltration, reverse osmosis and mineralization) working in parallel. Seven sampling points within the different process stages were characterized monthly during 2014. A global Parallel Factor Analysis (PARAFAC) was used to pull out underlying organic fractions from the fluorescence spectra. Accordingly a five components model was selected to describe the system and the pros and cons of the model were discussed by analysis of the residuals. Among the five fluorescent components, those associated to humic-like matter (C1, C3 and C4) showed a similar season variability in the river water feeding the DWTP (which resembled that of UV₂₅₄ and TOC), whereas the two components associated to protein-like matter (C2 and C5) exhibited a different behavior. The maximum fluorescence intensity values (Fmax) were used to quantify DOM removals across the plant. Compared to the conventional line, water from the UF/RO membrane-based line showed between 6 and 14 times lower fluorescence intensity signal for the humic-like components and between 1 and 3 for the protein-like components as compared to the conventional line. The differences in DOM composition due to seasonal variations and along the treatment trains point out the suitability of using fluorescence measurements over other parameters such as UV₂₅₄ as a monitoring tool to help optimize operation conditions of each treatment stage and improve produced water quality in a DWTP.

Factors associated with seminal impairment in HIV-infected men under antiretroviral therapy

STUDY QUESTION

How do semen parameters of HIV-infected men under antiretroviral treatment compare with WHO parameters of normal semen, and what factors are associated with any differences?

SUMMARY ANSWER

Semen quality in most HIV-infected patients under antiretroviral treatment exceeds WHO limits, but the number falling below them is higher than would be expected in a healthy population. Exposure to efavirenz has a significant association with dysmotility.

WHAT IS KNOWN ALREADY

Dysmotility is the most frequently described sperm alteration related to HIV infection, and it has recently been linked to treatment with non-nucleoside reverse transcriptase inhibitors, particularly to efavirenz.

STUDY DESIGN, SIZE, DURATION

Prospective cohort study. Between March 2002 and December 2013, 139 HIV-infected men undergoing antiretroviral therapy were enrolled.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants were male members of serodiscordant couples who attended a clinic for sexually transmitted infections (STIs) in Madrid and requested reproductive counselling. Sociodemographic, behavioural and clinical data were collected. CD4⁺ lymphocyte count, HIV viral load, serology/viral load of hepatitis B and C viruses, syphilis serology and other STIs diagnosis were performed. Semen parameters were assessed through standard sperm analysis and were compared with WHO 2010 reference values. Factors associated with impaired semen parameters were evaluated by bivariate and multivariate analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

The median values of all assessed semen parameters were within a normal range, but in up to 19% of HIV-positive males, at least one parameter of semen quality was below the normal range. A significant association between treatment with efavirenz and the presence of dysmotility was detected in the multivariate analysis.

LIMITATIONS, REASONS FOR CAUTION

Our results cannot demonstrate a causal relationship between exposure to efavirenz and impaired motility. We do not have a real comparison group as the WHO cohort is international and may not reflect local variations in semen characteristics. Subjects who requested reproductive counselling might not be representative of HIV-positive men in general.

WIDER IMPLICATIONS OF THE FINDINGS

Since efavirenz is still widely used in current therapeutic regimens may be affecting fertility in seropositive men who desire procreation.

STUDY FUNDING/COMPETING INTERESTS

No external funding was used for this study. The authors have no conflict of interest to declare.

Altered metabolism of gut microbiota contributes to chronic immune activation in HIV-infected individuals

Altered interplay between gut mucosa and microbiota during treated HIV infection may possibly contribute to increased bacterial translocation and chronic immune activation, both of which are predictors of morbidity and mortality. Although a dysbiotic gut microbiota has recently been reported in HIV+ individuals, the metagenome gene pool associated with HIV infection remains unknown. The aim of this study is to characterize the functional gene content of gut microbiota in HIV+ patients and to define the metabolic pathways of this bacterial community, which is potentially associated with immune dysfunction. We determined systemic markers of innate and adaptive immunity in a cohort of HIV-infected individuals on successful antiretroviral therapy without comorbidities and in healthy non-HIV-infected subjects. Metagenome sequencing revealed an altered functional profile, with enrichment of the genes involved in various pathogenic processes, lipopolysaccharide biosynthesis, bacterial translocation, and other inflammatory pathways. In contrast, we observed depletion of genes involved in amino acid metabolism and energy processes. Bayesian networks showed significant interactions between the bacterial community, their altered metabolic pathways, and systemic markers of immune dysfunction. This study reveals altered metabolic activity of microbiota and provides novel insight into the potential host-microbiota interactions driving the sustained inflammatory state in successfully treated HIV-infected patients.

Isolation and characterization of 20 polymorphic microsatellite loci in the migratory freshwater fish Leporinus obtusidens (Characiformes: Anostomidae) using 454 shotgun pyrosequencing

Twenty polymorphic microsatellite markers were developed for the Neotropical fish Leporinus obtusidens using a next generation sequencing approach and tested in two other characifomes species, Schizodon platae and Prochilodus lineatus. Microsatellite loci alleles in L. obtusidens ranged between 2 and 20 alleles per locus (mean = 5·7), with expected heterozygosity values ranging from 0·097 to 0·956 (mean = 0·578) and observed heterozygosity values ranging from 0·000 to 0·800 (mean = 0·400) in a sample of 20 specimens from the lower Paraná River (Argentina). Most of these markers will be a valuable tool for captive breeding and stocking programmes, as well as for analyses of population connectivity and genetic structure in this broadly distributed Neotropical migratory fish.

Use of lectins to in situ visualize glycoconjugates of extracellular polymeric substances in acidophilic archaeal biofilms

Biofilm formation and the production of extracellular polymeric substances (EPS) by meso- and thermoacidophilic metal-oxidizing archaea on relevant substrates have been studied to a limited extent. In order to investigate glycoconjugates, a major part of the EPS, during biofilm formation/bioleaching by archaea on pyrite, a screening with 75 commercially available lectins by fluorescence lectin-binding analysis (FLBA) has been performed. Three representative archaeal species, Ferroplasma acidiphilum DSM 28986, Sulfolobus metallicus DSM 6482^T and a novel isolate Acidianus sp. DSM 29099 were used. In addition, Acidianus sp. DSM 29099 biofilms on elemental sulfur were studied. The results of FLBA indicate (i) 22 lectins bound to archaeal biofilms on pyrite and 21 lectins were binding to Acidianus sp. DSM 29099 biofilms on elemental sulfur; (ii) major binding patterns, e.g. tightly bound EPS and loosely bound EPS, were detected on both substrates; (iii) the three archaeal species produced various EPS glycoconjugates on pyrite surfaces. Additionally, the substratum induced different EPS glycoconjugates and biofilm structures of cells of Acidianus sp. DSM 29099. Our data provide new insights into interactions between acidophilic archaea on relevant surfaces and also indicate that FLBA is a valuable tool for in situ investigations on archaeal biofilms.

Trends in HIV testing, prevalence among first-time testers, and incidence in most-at-risk populations in Spain: the EPI-VIH Study, 2000 to 2009

During 2000 to 2009, data on people undergoing HIV testing and on those newly diagnosed with HIV were collected in a network of 20 Spanish clinics specialising in sexually transmitted infections and/or HIV testing and counselling. The number of tests performed, overall and disaggregated by different variables, was obtained. HIV prevalence among first-time testers and HIV incidence among repeat testers were calculated. To evaluate trends, joinpoint regression models were fitted. In total, 236,939 HIV tests were performed for 165,745 individuals. Overall HIV prevalence among persons seeking HIV testing was 2.5% (95% CI: 2.4 to 2.6). Prevalence was highest in male sex workers who had sex with other men (19.0% (95% CI: 16.7 to 21.4)) and was lowest in female sex workers (0.8% (95% CI: 0.7 to 0.9)). Significant trends in prevalence were observed in men who have sex with men (MSM) (increasing) and heterosexual individuals (decreasing). The incidence analysis included 30,679 persons, 64,104 person-years (py) of follow-up and 642 seroconversions. The overall incidence rate (IR) was 1.0/100 py (95% CI: 0.9/100 to 1.1/100). Incidence was significantly higher in men and transgender females than in women (1.8/100 py (95% CI: 1.6 to 1.9), 1.2/100 py (95% CI: 0.5 to 2.8) and 0.1/100 py (95% CI: 0.09 to 0.2) respectively) and increased with age until 35–39 years. IRs in MSM and people who inject drugs were significantly greater than in heterosexual individuals (2.5/100 py (95% CI: 2.3 to 2.7), 1.6/100 py (95% CI: 1.1 to 2.2) and 0.1/100 py (95% CI: 0.09 to 0.2) respectively), and an upward trend was observed in MSM. Our results call for HIV prevention to be reinforced in MSM and transgender women in Spain.

Elimination of large uremic toxins by a dialyzer specifically designed for high-volume convective therapies

BACKGROUND

Unlike conventional hemodialysis treatments, which rely almost solely on diffusion-related mechanisms for solute removal, hemodiafiltration (HDF) allows more efficient removal of higher molecular weight toxins due to convective transport mechanisms. To facilitate the removal of these toxins in HDF treatment modalities, dialyzers with highly efficient high-flux membranes are necessary. This study assessed the large uremic toxin removal ability of a high-flux dialyzer (FX CorDiax 60) specifically designed to facilitate convective therapies compared with a standard high-flux dialyzer (FX 60).

METHODS

In an open, randomized, cross-over, single-center, controlled, prospective clinical study, 30 adult chronic hemodialysis patients were treated by post-dilution online HDF with the FX 60 or the FX CorDiax 60 dialyzer. All other dialysis parameters were kept constant in both study arms. The reduction rate (RR) of blood urea nitrogen, phosphate, β2-microglobulin (β2-m), myoglobin, prolactin, α1-microglobulin, α1-acid glycoprotein, albumin and total protein as well as the elimination into dialysate was intraindividually compared for the two dialyzer types.

RESULTS

For FX CorDiax 60 versus FX 60, the RR was significantly higher for blood urea nitrogen (86.23 ± 4.14 vs. 84.89 ± 4.59%, p = 0.015), β2-m (84.67 ± 3.79 vs. 81.30 ± 4.82%, p < 0.0001), myoglobin (75.23 ± 10.48 vs. 58.60 ± 12.1%, p < 0.0001), prolactin (72.96 ± 9.68 vs. 56.91 ± 13.01%, p < 0.0001) and α1-microglobulin (20.89 ± 18.27 vs. 13.60 ± 12.50%, p = 0.016). There were no significant differences in the RR for phosphate, α1-acid glycoprotein, albumin and total protein. Mass removal was significantly higher with the FX CorDiax 60 than with the FX 60 for β2-m (0.26 ± 0.09 vs. 0.24 ± 0.09 g, p = 0.0006), myoglobin (1.83 ± 0.89 vs. 1.51 ± 0.76 mg, p = 0.0017), prolactin (0.17 ± 0.13 vs. 0.14 ± 0.08 mg, p = 0.02) and albumin (4.25 ± 3.49 vs. 3.01 ± 2.37 g, p = 0.03).

CONCLUSIONS

This study demonstrates that treating patients with an FX CorDiax 60 instead of an FX 60 dialyzer in post-dilution HDF mode significantly increases the elimination of middle molecules.

Immune response to intrathecal enzyme replacement therapy in mucopolysaccharidosis I patients

BACKGROUND

Intrathecal (IT) enzyme replacement therapy with recombinant human α-L-iduronidase (rhIDU) has been studied to treat glycosaminoglycan storage in the central nervous system of mucopolysaccharidosis (MPS) I dogs and is currently being studied in MPS I patients.

METHODS

We studied the immune response to IT rhIDU in MPS I subjects with spinal cord compression who had been previously treated with intravenous rhIDU. We measured the concentrations of specific antibodies and cytokines in serum and cerebrospinal fluid (CSF) collected before monthly IT rhIDU infusions and compared the serologic findings with clinical adverse event (AE) reports to establish temporal correlations with clinical symptoms.

RESULTS

Five MPS I subjects participating in IT rhIDU trials were studied. One subject with symptomatic spinal cord compression had evidence of an inflammatory response with CSF leukocytosis, elevated interleukin-5, and elevated immunoglobulin G. This subject also complained of lower back pain and buttock paresthesias temporally correlated with serologic abnormalities. Clinical symptoms were managed with oral medication, and serologic abnormalities were resolved, although this subject withdrew from the trial to have spinal decompressive surgery.

CONCLUSION

IT rhIDU was generally well tolerated in the subjects studied, although one subject had moderate to severe clinical symptoms and serologic abnormalities consistent with an immune response.

Clinical and epidemiological characterization of a lymphogranuloma venereum outbreak in Madrid, Spain: co-circulation of two variants

The lymphogranuloma venereum (LGV) outbreak described in the Netherlands in 2003, increased the interest in the genotyping of Chlamydia trachomatis. Although international surveillance programmes were implemented, these studies slowly decreased in the following years. Now data have revealed a new accumulation of LGV cases in those European countries with extended surveillance programmes. Between March 2009 and November 2011, a study was carried out to detect LGV cases in Madrid. The study was based on screening of C. trachomatis using commercial kits, followed by real-time pmpH-PCR discriminating LGV strains, and finally ompA gene was sequenced for phylogenetic reconstruction. Ninety-four LGV infections were identified. The number of cases increased from 10 to 30 and then to 54 during 2009-2011. Incidence of LGV was strongly associated with men who have sex with men; but in 2011, LGV cases were described in women and heterosexual men. Sixty-nine patients were also human immunodeficiency virus (HIV) positive, with detectable viral loads at the moment of LGV diagnosis, suggesting a high-risk of co-transmission. In fact, in four patients the diagnosis of HIV was simultaneous with LGV infection. The conventional treatment with doxycycline was prescribed in 75 patients, although in three patients the treatment failed. The sequencing of the ompA gene permitted identification of two independent transmission nodes. One constituted by 25 sequences identical to the L2b variant, and a second node including 37 sequences identical to L2. This epidemiological situation characterized by the co-circulation of two LGV variants has not been previously described, reinforcing the need for screening and genotyping of LGV strains.

Percepción de docentes y estudiantes acerca de la actividad educativa en la escuela de enfermería de la UNMSM y propuesta co-participativa de planes de mejora

Objetivos: Caracterizar la actividad académica, el cumplimiento de las obligaciones, programa, metodología, materiales, actitud del docente, evaluación, prácticas, satisfacción. Establecer las coincidencias y divergencias de la actividad educativa en Enfermería. Y comprometer a los involucrados a participar en el diseño de propuestas. Diseño: Método descriptivo, transversal, cuantitativo, complementado con técnicas cualitativas. Institución: Departamento Académico Profesional de Enfermería, Facultad de Medicina, UNMSM. Participantes: Estudiantes y docentes. Intervenciones: Se efectuó el estudio en 135 estudiantes y 27 docentes (30% del universo de docentes y estudiantes). La escala fue de 1 a 5, siendo 1 definitivamente negativa y 5 definitivamente positiva. Principales medidas de resultados: Calidad de la actividad académica. Resultados: En estudiantes fue 3,57 y en docentes 3,70, indicando que estamos cercanos al punto medio y lejos de calidad ‘definitivamente positiva’. El menor valor fue la dimensión ‘prácticas’, con un valor de 2,74, con ‘opinión negativa’. El valor más alto estuvo en ‘Programa de Enseñanza’, con 3,91, cerca de ‘opinión positiva’. Conclusiones: Hubo dos categorías de resultados, actitud docente y aptitud docente, señalando que los docentes se mantienen ‘sin interés’, ‘poco comprometidos’ con su labor docente. Falta mejorar la planificación de clases, metodología, supervisión y evaluación; un mejor uso del tiempo, para no afectar la ‘práctica clínica o comunitaria’.

Exploitation of a turbot (Scophthalmus maximus L.) immune-related expressed sequence tag (EST) database for microsatellite screening and validation

In this study, we identified and characterized 160 microsatellite loci from an expressed sequence tag (EST) database generated from immune-related organs of turbot (Scophthalmus maximus). A final set of 83 new polymorphic microsatellites were validated after the analysis of 40 individuals of Atlantic origin including both wild and farmed individuals. The allele number and the expected heterozygosity ranged from 2 to 18 and from 0.021 to 0.951, respectively. Evidences of null alleles at moderate-high frequencies were detected at six loci using population data. None of the analysed loci showed deviations from Mendelian segregation after the analysis of five full-sib families including approximately 92 individuals/family. The markers are used to consolidate the turbot genetic map, and because they are mostly EST-derived, they will be very useful for comparative genomic studies within flatfishes and with model fish species. Using an in silico approach, we detected significant homologies of microsatellite sequences with the EST databases of the flatfish species with highest genomic resources (Senegalese sole, Atlantic halibut, bastard halibut) in 31% of these turbot markers. The conservation of these microsatellites within Pleuronectiformes will pave the way for anchoring genetic maps of different species and identifying genomic regions related to productive traits.

Adding condensed tannins to the diet increases ovulation rate in sheep

The objective of the present study was to investigate whether adding condensed tannins (T) to the diet of sheep increases ovulation rate (OR). In all, 281 mature Polwarth ewes (49.9 ± 6.0 kg and body condition score (BCS) of 2.02 ± 0.24 units) were heat-synchronised (oestrus = Day 1) and sorted in the following four treatment diets: (1) native pasture alone (82.6 g of CP and 8.4 MJ metabolisable energy (ME)/kg DM) (NP; n = 70); (2) native pasture (NP) plus a supplement of 0.45 kg of soybean meal (S) from Day 10 to Day 14 (NP+S; n = 71); (3) NP plus a supplement of 0.45 kg S and 25 g of T, to get an estimated concentration of T in the diet of 1.5% (NP+S+1.5T; n = 69); and (4) NP plus a supplement of 0.45 kg S and 42 g of T, to get a concentration of T of 2.5% (NP+S+2.5T; n = 71). OR was measured 8 days after the second heat by rectal ultrasound (Day 25). The estimated consumption of crude protein (CP) during the supplementation period was 129, 261, 237 and 200 g/ewe.day for NP, NP+S, NP+S+1.5T and NP+S+2.5T ewes, respectively. NP+S+1.5T ewes had an OR of 1.90, which was higher (P < 0.05) than those for NP+S+2.5T and NP+S ewes (1.68 and 1.70, respectively). All supplemented ewes had a higher OR than did NP ewes (1.48, P < 0.05). Although NP+S+1.5T ewes ate less protein than did NP+S ewes, their OR was higher, as a result of a more effective use of the protein. The higher concentrations of 2.5% T in the diet might have not evoked a response in OR.

Permanent genetic resources added to Molecular Ecology Resources Database 1 December 2010-31 January 2011

This article documents the addition of 238 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Alytes dickhilleni, Arapaima gigas, Austropotamobius italicus, Blumeria graminis f. sp. tritici, Cobitis lutheri, Dendroctonus ponderosae, Glossina morsitans morsitans, Haplophilus subterraneus, Kirengeshoma palmata, Lysimachia japonica, Macrolophus pygmaeus, Microtus cabrerae, Mytilus galloprovincialis, Pallisentis (Neosentis) celatus, Pulmonaria officinalis, Salminus franciscanus, Thais chocolata and Zootoca vivipara. These loci were cross-tested on the following species: Acanthina monodon, Alytes cisternasii, Alytes maurus, Alytes muletensis, Alytes obstetricans almogavarii, Alytes obstetricans boscai, Alytes obstetricans obstetricans, Alytes obstetricans pertinax, Cambarellus montezumae, Cambarellus zempoalensis, Chorus giganteus, Cobitis tetralineata, Glossina fuscipes fuscipes, Glossina pallidipes, Lysimachia japonica var. japonica, Lysimachia japonica var. minutissima, Orconectes virilis, Pacifastacus leniusculus, Procambarus clarkii, Salminus brasiliensis and Salminus hilarii.

Microspheres from new biodegradable poly(ester amide)s with different ratios ofL- andD-alanine for controlled drug delivery

A series of biodegradable poly (ester amide)s composed of sebacic acid, dodecanediol and different ratios of the stereoisomers of L- and D-alanine were synthesized for applications in drug delivery systems. Microspheres loaded with diclofenac sodium salt, triclosan and clofazimine were prepared with the solvent evaporation technique. No influence of polymer constitution in the drug release rate was found in vitro and no degradation occurred during the period of drug release. It was shown that a sustained delivery of the hydrophilic diclofenac sodium salt in Sörensen media occurred and it was controlled by diffusion. However, exhaustion of microspheres was feasible only from the most porous matrices where channelling had an important contribution.

Characterization of EST-derived microsatellites for gene mapping and evolutionary genomics in turbot

The detection of microsatellite sequences within expressed sequence tags (ESTs) connects potential markers with specific genes, generating type I markers. We have developed and mapped by linkage analysis a set of EST-derived microsatellites in the turbot, Scophthalmus maximus. One hundred and ninety-one microsatellites were identified from 9256 turbot ESTs. Primer design was possible with 98 microsatellites. After genotyping 25 wild turbot and the parents of two reference families for linkage analysis, 43 EST-derived microsatellites were selected because they met technical and polymorphism criteria. A final set of 31 EST-derived microsatellites could be mapped to 17 linkage groups of the turbot consensus map based on 242 anonymous microsatellites. Twenty-four microsatellite-containing ESTs were functionally annotated, confirming them as type I markers. Nineteen were mapped in the turbot consensus map. These EST-derived microsatellites constitute useful tools for genome scanning of turbot populations, marker-assisted selection programmes and comparative mapping.

[How much should dialysis time be increased when catheters are used?]

The use of central catheters in hemodialysis patients as a permanent vascular access has increased during the last years, reaching numbers of around 7% of prevalent patients and between 25% of incident patients. Although the current catheters allow higher sanguineous flows with smaller incidence of infectious complications and dysfunction, the dose of dialysis that is reached is still inferior to that obtained with native arterio-venous fistula (AVF) and grafts. The aim of the present study was to evaluate the possible additional time supposed by dialysis using central venous catheters with respect to habitual vascular access as a consequence of the lesser blood flow (Qb) and the irregularity of its function (frequent lowering of the Qb and necessity of inverting the lines on many occasions). A total of 48 patients (31 men/17 women) with an average age of 61,6 +/- 14 years old (rank: 28-83), 20 with tunnelled catheter and the remaining with AVF, were included in the study. All the patients were dialyzed in the modality of high flux hemodialysis with a polisulphone of 1,9 m2 dialyzer, dialysis time of 240 minutes, dialysate flow 500 ml/min and monitors equipped with ionic dialysance (ID) with the objective of obtaining a Kt of 45 litres with each one of the different vascular accesses. The patients with AVF received 3 sessions, with variations of Qb to 300, 350 and 400 ml/min. The patients with tunnelled catheter received two sessions, to the maximum Qb, one with normal connection and other with inverted one. In the results obtained it is possible to emphasize that only the patients with AVF and 400 ml/min reached the objective of 45 L of Kt. The patients with AVF needed to increase 12 minutes of hemodialysis with a Qb of 350 ml/min and 28 minutes with a Qb of 300 ml/min; the catheters on normal position needed to increase 24 minutes and finally in the inverted catheters an increase of 59 minutes was necessary to reach the same Kt objective. We concluded that the patients dialyzed with central catheters on average needed to increase by 30 minutes the time of dialysis if the catheter worked in a normal position but 60 minutes if the arterio-venous lines were inverted so as to reach the minimum dose of dialysis.

[Kt as control and follow-up of the dose at a hemodialysis unit]

To ensure our patients are receiving an adequate dose in every dialysis session there must be a target to achieve this in the short or medium term. The incorporation during the last years of the ionic dialysance (ID) in the monitors, has provided monitoring of the dialysis dose in real time and in every dialysis session. Lowrie y cols., recommend monitoring the dose with Kt, recommending at least 40 L in women and 45 L in men or individualizing the dose according to the body surface area. The target of this study was to monitor the dose with Kt in every dialysis session for 3 months, and to compare it with the monthly blood test. 51 patients (58% of our hemodialysis unit), 32 men and 19 women, 60.7+/-14 years old, in the hemodialysis programme for 37.7+/-52 months, were dialysed with a monitor with IC. The etiology of their chronic renal failure was: 3 tubulo-interstitial nephropathy, 9 glomerulonephritis, 12 vascular disease, 7 polycystic kidney disease, 7 diabetic nephropathy and 13 unknown. 1,606 sessions were analysed during a 3 month period. Every patient was treated with the usual parameters of dialysis with 2.1 m2 cellulose diacetate (33.3%), 1.9 m2 polisulfone (33.3%) or 1.8 m2 helixone, dialysis time of 263+/-32 minutes, blood flow of 405+/-66, with dialysate flow of 712+/-138 and body weight of 66.7+/-14 kg. Initial ID, final ID and Kt were measured in each session. URR and Kt/V were obtained by means of a monthly blood test. The initial ID was 232+/-41 ml/min, the final ID was 197+/-44 ml/min, the mean of Kt determinations was 56.6+/-14 L, the mean of Kt/V was 1.98+/-0.5 and the mean of URR was 79.2+/-7%. Although all patients were treated with a minimum recommended dose of Kt/V and URR when we used the Kt according to gender, we observed that 31% of patients do not get the minimum dose prescribed (48.1+/-2.4 L), 34.4% of the men and 26.3% of the women. If we use the Kt individualized for the body surface area, we observe that 43.1% of the patients do not get the minimum dose prescribed with 4.6+/-3.4 L less than the dose prescribed. We conclude that the monitoring of dialysis dose with the Kt provides a better discrimination detecting that between 30 and 40% of the patients perhaps do not get an adequate dose for their gender or body surface area.

[Control of hypertension refractory to medical management by means of short daily hemodialysis]

Hypertension is a very frequent complication in patients in hemodialysis. A high percentage of the patients on standard hemodialysis remain hypertense in spite of intensive pharmacologic treatment. We presented the case of a hypertense patient with difficult control in spite of antihypertensive treatment with five drugs and several secondary complications. The change to a short daily hemodialysis was successful to hypertension control and allowed a gradual suspension of drugs.

Hepatic stellate cells and alcoholic liver disease

Liver fibrosis represents a significant health problem worldwide for which no effective therapy exists. A great deal of research has been carried out to understand the molecular mechanisms responsible for the development of liver fibrosis. Activated stellate cells are the primary cell type responsible for the production of collagen I, the key protein involved in the development of liver fibrosis. Excessive deposition of collagen I occurs along with impaired extracellular matrix remodeling. Following a fibrogenic stimulus stellate cells transform into an activated collagen type I-producing cell. Numerous changes in gene expression are associated with stellate cell activation, including the induction of several intracellular signaling cascades, which help maintain the activated phenotype and control the fibrogenic and proliferative state of the cell. Activation of stellate cells is mediated by factors released from hepatocytes and Kupffer cells as they produce reactive oxygen species, nitric oxide, cytokines, growth factors, and cyclooxygenase and lipoxygenase metabolites, which provide pivotal paracrine effects in the liver milieu. Inhibition of stellate cell activation, proliferation, and the increased production of extracellular matrix (i.e. collagen type I) are therefore crucial steps for intervention in hepatic fibrogenesis.

Liver transduction with a simian virus 40 vector encoding insulin-like growth factor I reduces hepatic damage and the development of liver cirrhosis

Liver transplantation is the only treatment for advanced liver cirrhosis. Therapies halting the progression of the disease are urgently needed. Administration of recombinant insulin-like growth factor-I (rIGF-I) induces hepatoprotective effects in experimental cirrhosis. Therefore, we analyzed the efficacy of a recombinant simian virus 40 vector (rSV40) encoding IGF-I (rSVIGF-I) to prevent cirrhosis progression. First, transgene expression was evaluated in mice injected with rSV40 encoding luciferase, which showed long-term hepatic expression of the transgene. Interestingly, luciferase expression increased significantly in CCl(4)-damaged livers and upon IGF-I administration, thus liver injury and IGF-I expression from rSVIGF-I should favor transgene expression. rSVIGF-I therapeutic efficacy was studied in rats where liver cirrhosis was induced by CCl(4) inhalation during 36 weeks. At the end of the study, the hepatic levels of IGF-I and IGF-binding protein 3 were higher in rSVIGF-I-treated rats than in control cirrhotic animals. Cirrhotic rats treated with rSVIGF-I had reduced serum bilirubin, transaminases and liver fibrosis scores and increased hepatic expression of hepatocyte growth factor and STAT3alpha as compared to cirrhotic animals. Furthermore, cirrhotic animals showed testis atrophy and altered spermatogenesis, whereas testicular size and histology were normal in cirrhotic rats that received rSVIGF-I. Therefore, rSV40-mediated sustained expression of IGF-I in the liver slowed cirrhosis progression.

Serum Protein S-100 Predicts Clinical Outcome in Patients with Melanoma Treated with Adjuvant Interferon – Comparison with Tyrosinase RT-PCR

OBJECTIVE

To study the clinical value of the determination of serum S-100 protein as a single tumor marker or in combination with tyrosinase RT-PCR in patients with melanoma receiving adjuvant interferon.

PATIENTS AND METHODS

Patients were tested for serum S-100 protein luminoimmunometric assay and for blood tyrosinase mRNA (RT-PCR), before starting interferon and every 2-3 months thereafter.

RESULTS

One hundred and six patients (stage IIA, 27; IIB, 19; III, 49; and IV, 11) were included in the study. Median follow-up was 51 months (range 2-76). In the univariate analysis, under treatment S-100 > or =0.15 microg/l and a positive RT-PCR correlated with a lower disease-free survival and overall survival (OS). In the multivariate analysis, clinical stage, under therapy positive RT-PCR and S-100 levels > or =0.15 mug/ml, were independent prognostic factors for OS. The hazard ratio for OS was 3.9 (95% CI, 1.67-9.15; p = 0.004) and 2.2 (95% CI, 1.05-4.6; p = 0.016) for S-100 > or =0.15 microg/l and positive RT-PCR, respectively. When both techniques where combined, a positive RT-PCR indicated a poorer clinical outcome only in patients with S-100 <0.15 microg/l.

CONCLUSIONS

S-100 > or =0.15 microg/l and a positive RT-PCR during adjuvant interferon therapy indicate a high risk of death in resected melanoma patients. S-100 determination has a higher positive predictive value than RT-PCR, while tyrosinase RT-PCR adds prognostic information in patients with S-100 <0.15 microg/l.

[Treatment with the placement of carotid stent of jugular-carotid fistula after the insertion of hemodialysis catheter]

The use of jugular temporary catheters as vascular access for hemodialysis, entails a risk of various complications. The most frequent problems are the arterial puncture and haematoma. However, there are other less frequent potentially serious complications, which constitute a therapeutic and diagnostic challenge for the nephrologists. We present a case of a patient that developed an acute renal failure in the context of cellulites for E. Coli treated with aminoglycosid, who required renal treatment with haemodialysis. After the placement of a polyurethane double-lumen catheter with ultrasound guidance at the level of the internal jugular vein, arterial blood streaming was observed through the lumen of the catheter. The angiographic study showed the tipo of the catheter placed at the level of the aortic arch. Ultrasound exam clearly despicted the track between the internal jugular vein and the internal carotid artery. An effective closing of the fistula was achieved with the placement of a covered stent-graft with the simultaneous withdrawal of the catheter. Reviewing the literature this is the first reported case of an iatrogenic jugulo-carotid fistula secundary to placement of hemodialysis catheter resolved by the implantation of carotid stent-graft.