A Psychometric Evaluation and a Framework Test of the HIV Stigma Mechanisms Scale Among a Population-Based Sample of Men and Women Living with HIV in Central Uganda.

HIV stigma is a critical barrier to HIV prevention and care. This study evaluates the psychometric properties of the HIV Stigma Mechanisms Scale (HIV-SMS) among people living with HIV (PLHIV) in central Uganda and tests the underlying framework. Using data from the PATH/Ekkubo study, (n = 804 PLHIV), we assessed the HIV-SMS' reliability and validity (face, content, construct, and convergent). We used multiple regression analyses to test the HIV-SMS' association with health and well-being outcomes. Findings revealed a more specific (5-factor) stigma structure than the original model, splitting anticipated and enacted stigmas into two subconstructs: family and healthcare workers (HW). The 5-factor model had high reliability (α = 0.92-0.98) and supported the convergent validity (r = 0.12-0.42, p < 0.01). The expected relationship between HIV stigma mechanisms and health outcomes was particularly strong for internalized stigma. Anticipated-family and enacted-family stigma mechanisms showed partial agreement with the hypothesized health outcomes. Anticipated-HW and enacted-HW mechanisms showed no significant association with health outcomes. The 5-factor HIV-SMS yielded a proper and nuanced measurement of HIV stigma in central Uganda, reflecting the importance of family-related stigma mechanisms and showing associations with health outcomes similar to and beyond the seminal study.

Development and validation of a video-assisted liver biopsy technique using a minimally-invasive device.

BACKGROUND: Percutaneous liver biopsy is the gold standard technique for establishing the cause of cirrhosis and liver disease activity assessment. However, some cases of steatohepatitis or other chronic liver diseases show a high number of false negative results in samples obtained via the percutaneous route. This fact justifies performing a liver biopsy via the laparoscopic route. However, this is an expensive technique, with morbidities associated with pneumoperitoneum and anesthetic complications. The main objective of this study is to develop a video-assisted technique that uses only a minimally-invasive device for the liver biopsy and the optical trocar. Without additional trocars, this technique constitutes a less invasive procedure than the existing techniques in clinical practice. METHODS: This is a device development and validation study and patients submitted to abdominal laparoscopic surgery and required liver biopsy for moderate to severe steatosis were recruited. The patients were randomized into two groups: laparoscopic liver biopsy technique (n = 10, control group) and mini-laparoscopic liver biopsy technique (n = 8, experimental group). The times associated with procedure performance in both groups were evaluated using the Mann-Whitney or Kruskal-Wallis tests according to data distribution. RESULTS: At baseline, there was no statistical difference regarding gender and type of surgery. The experimental group had a significantly shorter time compared with the group that underwent the traditional procedure in mean procedure time (p = 0.003), biopsy time (p = 0.002) and hemostasis time (p = 0.003). CONCLUSIONS: The mini-laparoscopic biopsy device and technique showed to be capable of safely obtaining sufficient tissue samples, which was minimally invasive and in a shorter time than the classic technique.

Purification, biochemical characterization of a lectin from marine sponge Ircinia strobilina and its effect on the inhibition of bacterial biofilms.

A new lectin from marine sponge Ircinia strobilina, denominated IsL, was isolated by combination of affinity chromatography in Guar gum matrix followed by size exclusion chromatography. IsL was able to agglutinate native and enzymatically treated rabbit erythrocytes, being inhibited by galactosides, such as α-methyl-D-galactopyranoside, ß-methyl-D-galactopyranoside and α-lactose. IsL hemagglutinating activity was stable at neutral to alkaline pH, however the lectin loses its activity at 40° C. The molecular mass determinated by mass spectrometry was 13.655 ± 5 Da. Approximately 40% of the primary structure of IsL was determined by mass spectrometry, but no similarity was observed with any protein. The secondary structure of IsL consists of 28% α-helix, 26% ß-sheet, and 46% random region, as determined by dichroism circular. IsL was a calcium-dependent lectin, but no significant variations were observed by circular dichroism when IsL was incubated in presence of calcium and EDTA. IsL was not toxic against Artemia nauplii and did not have antimicrobial activity against bacterial cells. However, the IsL was able to significantly inhibit the biofilm formation of Staphylococcus aureus and Staphylococcus epidermidis.

Genetic control of cellular morphogenesis in Müller glia.

Cell shape is critical for the proper function of every cell in every tissue in the body. This is especially true for the highly morphologically diverse neural and glia cells of the central nervous system. The molecular processes by which these, or indeed any, cells gain their particular cell-specific morphology remain largely unexplored. To identify the genes involved in the morphogenesis of the principal glial cell type in the vertebrate retina, the Müller glia (MG), we used genomic and CRISPR based strategies in zebrafish (Danio rerio). We identified 41 genes involved in various aspects of MG cell morphogenesis and revealed a striking concordance between the sequential steps of anatomical feature addition and the expression of cohorts of functionally related genes that regulate these steps. We noted that the many of the genes preferentially expressed in zebrafish MG showed conservation in glia across species suggesting evolutionarily conserved glial developmental pathways.

The ciliary marginal zone of the zebrafish retina: clonal and time-lapse analysis of a continuously growing tissue.

Clonal analysis is helping us understand the dynamics of cell replacement in homeostatic adult tissues (Simons and Clevers, 2011). Such an analysis, however, has not yet been achieved for continuously growing adult tissues, but is essential if we wish to understand the architecture of adult organs. The retinas of lower vertebrates grow throughout life from retinal stem cells (RSCs) and retinal progenitor cells (RPCs) at the rim of the retina, called the ciliary marginal zone (CMZ). Here, we show that RSCs reside in a niche at the extreme periphery of the CMZ and divide asymmetrically along a radial (peripheral to central) axis, leaving one daughter in the peripheral RSC niche and the other more central where it becomes an RPC. We also show that RPCs of the CMZ have clonal sizes and compositions that are statistically similar to progenitor cells of the embryonic retina and fit the same stochastic model of proliferation. These results link embryonic and postembryonic cell behaviour, and help to explain the constancy of tissue architecture that has been generated over a lifetime.

Correction to: Seasonal dynamics of influenza in Brazil: the latitude effect.

Following publication.

Inhibitory neuron migration and IPL formation in the developing zebrafish retina.

The mature vertebrate retina is a highly ordered neuronal network of cell bodies and synaptic neuropils arranged in distinct layers. Little, however, is known about the emergence of this spatial arrangement. Here, we investigate how the three main types of retinal inhibitory neuron (RIN)--horizontal cells (HCs), inner nuclear layer amacrine cells (iACs) and displaced amacrine cells (dACs)--reach their specific laminar positions during development. Using in vivo time-lapse imaging of zebrafish retinas, we show that RINs undergo distinct phases of migration. The first phase, common to all RINs, is bipolar migration directed towards the apicobasal centre of the retina. All RINs then transition to a less directionally persistent multipolar phase of migration. Finally, HCs, iACs and dACs each undergo cell type-specific migration. In contrast to current hypotheses, we find that most dACs send processes into the forming inner plexiform layer (IPL) before migrating through it and inverting their polarity. By imaging and quantifying the dynamics of HCs, iACs and dACs from birth to final position, this study thus provides evidence for distinct and new migration patterns during retinal lamination and insights into the initiation of IPL formation.

Seasonal dynamics of influenza in Brazil: the latitude effect.

BACKGROUND: Influenza is a global transmissible disease. Its dynamics is far better understood in temperate climates than in the tropics. We aim to close this knowledge gap between tropical and temperate regions by showing how the influenza seasonality evolves in Brazil, a tropical country that encompasses a wide range of latitudes and six climatic sub-types. METHODS: We analyzed a state-level, weekly Syndrome of Acute Respiratory Disease (SARI) incidence data ranging from 2010 to 2016. We combined two techniques hierarchically: first the wavelet decomposition technique to detect annual periodicity and then circular statistics to describe seasonal measures of the periodic states. RESULTS: We found significant annual periodicity in 44% of the states. For these, we calculated several seasonal measures such as the center of gravity or mean timing of activity. The relationship between the seasonal signatures and latitude was clear and statistically significant. States with seasonal signature are clustered along the coast. Most Amazonian and Central West states exhibit no seasonal behavior. Among the seasonal states, influenza starts in Northeast region, spreading southbound. CONCLUSIONS: Our study advances the comprehension of influenza seasonality in tropical areas and could be used to design more effective prevention and control strategies.

Spectrum of Fates: a new approach to the study of the developing zebrafish retina.

The ability to image cells live and in situ as they proliferate and differentiate has proved to be an invaluable asset to biologists investigating developmental processes. Here, we describe a Spectrum of Fates approach that allows the identification of all the major neuronal subtypes in the zebrafish retina simultaneously. Spectrum of Fates is based on the combinatorial expression of differently coloured fluorescent proteins driven by the promoters of transcription factors that are expressed in overlapping subsets of retinal neurons. Here, we show how a Spectrum of Fates approach can be used to assess various aspects of neural development, such as developmental waves of differentiation, neuropil development, lineage tracing and hierarchies of fates in the developing zebrafish retina.

Health care to immigrant and Portuguese pregnant women in Portugal.

This study aimed to assess the care received and the barriers faced by immigrants and Portuguese pregnant women in Portugal. This is an exploratory qualitative study, resorting to applying semi-structured interviews to 60 immigrant and 22 Portuguese women. Content analysis supported by QSR Nvivo10 program was used. The study was approved by an Ethics Committee. The results showed four categories related to affective dimensions-relational, cognitive, technical-instrumental and health care policy for pregnant women. As for the barriers in health care, these were mentioned by some of the expectant mothers, especially immigrant women. Almost all, both immigrant and Portuguese, pregnant women were satisfied with the health care.

Origin and determination of inhibitory cell lineages in the vertebrate retina.

Multipotent progenitors in the vertebrate retina often generate clonally related mixtures of excitatory and inhibitory neurons. The postmitotically expressed transcription factor, Ptf1a, is essential for all inhibitory fates in the zebrafish retina, including three types of horizontal and 28 types of amacrine cell. Here, we show that specific types of inhibitory neurons arise from the cell-autonomous influence of Ptf1a in the daughters of fate-restricted progenitors, such as Ath5 or Vsx1/2-expressing progenitors, and that in the absence of Ptf1a, cells that would have become these specific inhibitory subtypes revert to the histogenetically appropriate excitatory subtypes of the same lineage. Altered proportions of amacrine subtypes respecified by the misexpression of Ptf1a in the Ath5 lineage suggest that Ath5-expressing progenitors are biased, favoring the generation of some subtypes more than others. Yet the full array of inhibitory cell subtypes in Ath5 mutants implies the existence of Ath5-independent factors involved in inhibitory cell specification. We also show that an extrinsic negative feedback on the expression of Ptf1a provides a control mechanism by which the number of any and all types of inhibitory cells in the retina can be regulated in this lineage-dependent way.

Surfactants in biorefineries: Role, challenges & perspectives.

The use of lignocellulosic biomass (LCB) as feedstock has received increasing attention as an alternative to fossil-based refineries. Initial steps such as pretreatment and enzymatic hydrolysis are essential to breakdown the complex structure of LCB to make the sugar molecules available to obtain bioproducts by fermentation. However, these steps increase the cost of the bioproduct and often reduces its competitiveness against synthetic products. Currently, the use of surfactants has shown considerable potential to enhance lignocellulosic biomass processing. This review addresses the main mechanisms and role of surfactants as key molecules in various steps of biorefinery processes, viz., increasing the removal of lignin and hemicellulose during the pretreatments, increasing enzymatic stability and enhancing the accessibility of enzymes to the polymeric fractions, and improving the downstream process during fermentation. Further, technical advances, challenges in application of surfactants, and future perspectives to augment the production of several high value-added bioproducts have been discussed.

Histological Inflammation in the Endoscopically Uninflamed Mucosa is Associated With Worse Outcomes in Limited Ulcerative Colitis.

BACKGROUND: The Montreal classification categorizes patients with ulcerative colitis (UC) based on their macroscopic disease extent. Independent of endoscopic extent, biopsies through all colonic segments should be retrieved during index colonoscopy. However, the prognostic value of histological inflammation at diagnosis in the inflamed and uninflamed regions of the colon has never been assessed. METHODS: This was a multicenter retrospective cohort study of newly diagnosed patients with treatment-naïve proctitis and left-sided UC. Biopsies from at least 2 colonic segments (endoscopically inflamed and uninflamed mucosa) were retrieved and reviewed by 2 pathologists. Histological features in the endoscopically inflamed and uninflamed mucosa were scored using the Nancy score. The primary outcomes were disease complications (proximal disease extension, need for hospitalization or colectomy) and higher therapeutic requirements (need for steroids or for therapy escalation). RESULTS: Overall, 93 treatment-naïve patients were included, with a median follow-up of 44 months (range, 2-329). The prevalence of any histological inflammation above the endoscopic margin was 71%. Proximal disease extension was more frequent in patients with histological inflammation in the endoscopically uninflamed mucosa at diagnosis (21.5% vs 3.4%, P = 0.04). Histological involvement above the endoscopic margin was the only predictor associated with an earlier need for therapy escalation (adjusted hazard ratio, 3.69; 95% confidence interval, 1.05-13.0); P = 0.04) and disease complications (adjusted hazard ratio, 4.79; 95% confidence interval, 1.10-20.9; P = 0.04). CONCLUSIONS: The presence of histological inflammation in the endoscopically uninflamed mucosa at the time of diagnosis was associated with worse outcomes in limited UC.

Simulated training model in a low cost for laparoscopic inguinal hernioplasty.

PURPOSE: Develop a 3D model for the simulation of laparoscopic inguinal hernioplasty transabdominal preperitoneal (TAPP). METHODS: This is an experimental study, 18 participants were selected, divided into three groups, experimental (GE) surgeons in training, control (GC) experienced surgeons and Shaw (GS) nonexperienced surgeons. The simulation in the 3D model was carried out in 6 sessions fulfilling the 5 stages. Opening the peritoneum with the creation of the preperitoneal space; identification of important structures; hernia identification and reduction; placement and fixation of the mesh in Cooper's ligament and closure of the peritoneum. RESULTS: In the 1st stage, the GE obtained an average of 1.25 ± 0.42 in the 1st session and 3.25 ± 0.62 in the 6th session (p = 0.05) and in the 5th stage 0.91 ± 0.29 in the first session. 1st session and 1.91 ± 0.29 in the 6th session (p = 0.001), with no significant difference between groups. The learning and skill curve in the SG represented 1.08 ± 0.29 1st and 3.50 ± 0.90 6th session (p = 0.001). CONCLUSIONS: The creation of a systematization of training in simulation applied to the three-dimensional model enabled gain in laparoscopic skills and underpinned its theoretical and practical foundations.

Neonatal Cholestasis Over Time: Changes in Epidemiology and Outcome in a Cohort of 154 Patients From a Portuguese Tertiary Center.

Introduction: In the last two decades there have been advances in the diagnosis and management of neonatal cholestasis, which may have changed its epidemiology, diagnostic accuracy, outcomes, and survival. Our goal was to characterize these changes over time in our setting. Methods: Retrospective cohort study in a tertiary center, enrolling patients born between January 1985 and October 2019. The cohort was divided into two periods, before (A; n = 67) and after (B; n = 87) the year 2000; and in two groups, according to patient's outcome (favorable, unfavorable). Overall survival and survival with and without orthotopic liver transplant (OLT) were evaluated in the two periods (A and B) and in different subgroups of underlying entities. Results: We found that the age of cholestasis recognition decreased significantly from period A to period B [median 43 days and 22 days, respectively, (p < 0.001)]; the changes in epidemiology were relevant, with a significant decrease in alpha-1-antitrypsin deficiency (p < 0.001) and an increase in transient cholestasis (p = 0.004). A next-generation sequencing (NGS) panel available since mid-2017 was applied to 13 patients with contributory results in 7, but, so far, only in 2 patients led to conclusive diagnosis of underlying entities. The number of cases of idiopathic cholestasis did not vary significantly. Over time there was no significant change in the outcome (p = 0.116). Overall survival and survival without OLT had no significant improvement during the period of observation (in periods A and B, 86 vs. 88%, and 85 vs. 87%, respectively). However, in period B, with OLT we achieved the goal of 100% of survival rate. Conclusions: Our data suggest that transient cholestasis became a very important subset of neonatal cholestasis, requiring specific guidance. The NGS panels can provide important inputs on disease diagnosis but, if applied without strict criteria and expertise, they can open a Pandora's box due to misinterpretation. Despite all the advances in accurate diagnosis and timely management-including early recognition of cholestasis-the improvement in patient outcomes and survival were still not significant.

Antibacterial activity of a new lectin isolated from the marine sponge Chondrilla caribensis.

A new lectin from the marine sponge Chondrilla caribensis (CCL) was isolated by affinity chromatography in Sepharose 6B media. CCL is a homotetrameric protein formed by subunits of 15,445 ±2Da. The lectin showed affinity for disaccharides containing galactose and mucin. Mass spectrometric analysis revealed about 50% of amino acid sequence of CCL, which showed similarity with a lectin isolated from Aplysina lactuca. Secondary structure consisted of 10% α-helix, 74% ß-sheet/ß-turn and 16% coil, and this profile was unaltered in a broad range of pH and temperatures. CCL agglutinated Staphylococcus aureus, S epidermidis and Escherichia coli, and it was able to reduce biofilm biomass, but showed no inhibition of planktonic growth of these bacteria. CCL activity was inhibited by α-lactose, indicating that Carbohydrate Recognition Domain (CRD) of the lectin was involved in antibiofilm activity.

Growth-factor-dependent phosphorylation of Bim in mitosis.

The regulation of survival and cell death is a key determinant of cell fate. Recent evidence shows that survival and death machineries are regulated along the cell cycle. In the present paper, we show that BimEL [a BH3 (Bcl-2 homology 3)-only member of the Bcl-2 family of proteins; Bim is Bcl-2-interacting mediator of cell death; EL is the extra-long form] is phosphorylated in mitosis. This post-translational modification is dependent on MEK (mitogen-activated protein kinase/extracellular-signal-regulated kinase kinase) and growth factor signalling. Interestingly, FGF (fibroblast growth factor) signalling seems to play an essential role in this process, since, in the presence of serum, inhibition of FGF receptors abrogated phosphorylation of Bim in mitosis. Moreover, we have shown bFGF (basic FGF) to be sufficient to induce phosphorylation of Bim in serum-free conditions in any phase of the cell cycle, and also to significantly rescue cells from serum-deprivation-induced apoptosis. Our results show that, in mitosis, Bim is phosphorylated downstream of growth factor signalling in a MEK-dependent manner, with FGF signalling playing an important role. We suggest that phosphorylation of Bim is a decisive step for the survival of proliferating cells.

Simulated training model in a low cost for laparoscopic inguinal hernioplasty

ABSTRACT Purpose Develop a 3D model for the simulation of laparoscopic inguinal hernioplasty transabdominal preperitoneal (TAPP). Methods This is an experimental study, 18 participants were selected, divided into three groups, experimental (GE) surgeons in training, control (GC) experienced surgeons and Shaw (GS) nonexperienced surgeons. The simulation in the 3D model was carried out in 6 sessions fulfilling the 5 stages. Opening the peritoneum with the creation of the preperitoneal space; identification of important structures; hernia identification and reduction; placement and fixation of the mesh in Cooper's ligament and closure of the peritoneum. Results In the 1st stage, the GE obtained an average of 1.25 ± 0.42 in the 1st session and 3.25 ± 0.62 in the 6th session (p = 0.05) and in the 5th stage 0.91 ± 0.29 in the first session. 1st session and 1.91 ± 0.29 in the 6th session (p = 0.001), with no significant difference between groups. The learning and skill curve in the SG represented 1.08 ± 0.29 1st and 3.50 ± 0.90 6th session (p = 0.001). Conclusions The creation of a systematization of training in simulation applied to the three-dimensional model enabled gain in laparoscopic skills and underpinned its theoretical and practical foundations.

L-Rhamnose-binding lectin from eggs of the Echinometra lucunter: Amino acid sequence and molecular modeling.

An L-rhamnose-binding lectin named ELEL was isolated from eggs of the rock boring sea urchin Echinometra lucunter by affinity chromatography on lactosyl-agarose. ELEL is a homodimer linked by a disulfide bond with subunits of 11 kDa each. The new lectin was inhibited by saccharides possessing the same configuration of hydroxyl groups at C-2 and C-4, such as L-rhamnose, melibiose, galactose and lactose. The amino acid sequence of ELEL was determined by tandem mass spectrometry. The ELEL subunit has 103 amino acids, including nine cysteine residues involved in four conserved intrachain disulfide bonds and one interchain disulfide bond. The full sequence of ELEL presents conserved motifs commonly found in rhamnose-binding lectins, including YGR, DPC and KYL. A three-dimensional model of ELEL was created, and molecular docking revealed favorable binding energies for interactions between ELEL and rhamnose, melibiose and Gb3 (Galα1-4Galß1-4Glcß1-Cer). Furthermore, ELEL was able to agglutinate Gram-positive bacterial cells, suggesting its ability to recognize pathogens.

A chromophore-containing agglutinin from Haliclona manglaris: purification and biochemical characterization.

A new chromophore-containing agglutinin (Haliclona manglaris agglutinin (HMA)) was isolated from the tropical sponge H. manglaris. HMA was purified by a combination of hydrophobic interaction chromatography and ion exchange chromatography. Native HMA is a heterotrimer formed by two ß-chains (15 kDa) and one α-chain (22 kDa). HMA is a glycoprotein and possesses three intrachain disulfide bonds. Hemagglutinating activity of HMA was stable at neutral pH and temperatures up to 60 °C. HMA was only inhibited by thyroglobulin. Mass spectrometry sequencing and Edman degradation revealed a unique amino acid sequence of about 30%. Moreover, HMA has an organic chromophore of 581 Da, and this characteristic seems to be important to its antioxidant activity. Interestingly, while HMA showed no toxicity against Artemia nauplii and was unable to agglutinate bacterial cells, it did show a high capacity to protect ß-carotene against oxidation. Thus, our findings suggest the putative involvement of HMA in the protection of the sponge against oxidation.