Colony stimulating factor-1 receptor drives glomerular parietal epithelial cell activation in focal segmental glomerulosclerosis

Parietal epithelial cells (PECs) are kidney progenitor cells with similarities to a bone marrow stem cell niche. In focal segmental glomerulosclerosis (FSGS) PECs become activated and contribute to extracellular matrix deposition. Colony stimulating factor-1 (CSF-1), a hematopoietic growth factor, acts via its specific receptor, CSF-1R, and has been implicated in several glomerular diseases, although its role on PEC activation is unknown. Here, we found that CSF-1R was upregulated in PECs and podocytes in biopsies from patients with FSGS. Through in vitro studies, PECs were found to constitutively express CSF-1R. Incubation with CSF-1 induced CSF-1R upregulation and significant transcriptional regulation of genes involved in pathways associated with PEC activation. Specifically, CSF-1/CSF-1R activated the ERK1/2 signaling pathway and upregulated CD44 in PECs, while both ERK and CSF-1R inhibitors reduced CD44 expression. Functional studies showed that CSF-1 induced PEC proliferation and migration, while reducing the differentiation of PECs into podocytes. These results were validated in the Adriamycin-induced FSGS experimental mouse model. Importantly, treatment with either the CSF-1R-specific inhibitor GW2580 or Ki20227 provided a robust therapeutic effect. Thus, we provide evidence of the role of the CSF-1/CSF-1R pathway in PEC activation in FSGS, paving the way for future clinical studies investigating the therapeutic effect of CSF-1R inhibitors on patients with FSGS.

Domestication signatures in the non-conventional yeast Lachancea cidri

Evaluating domestication signatures beyond model organisms is essential for a thorough understanding of the genotype-phenotype relationship in wild and human-related environments. Structural variations (SVs) can significantly impact phenotypes playing an important role in the physiological adaptation of species to different niches, including during domestication. A detailed characterization of the fitness consequences of these genomic rearrangements, however, is still limited in non-model systems, largely due to the paucity of direct comparisons between domesticated and wild isolates. Here, we used a combination of sequencing strategies to explore major genomic rearrangements in a Lachancea cidri yeast strain isolated from cider (CBS2950) and compared them to those in eight wild isolates from primary forests. Genomic analysis revealed dozens of SVs, including a large reciprocal translocation (~16 kb and 500 kb) present in the cider strain, but absent from all wild strains. Interestingly, the number of SVs was higher relative to single-nucleotide polymorphisms in the cider strain, suggesting a significant role in the strain's phenotypic variation. The set of SVs identified directly impacts dozens of genes and likely underpins the greater fermentation performance in the L. cidri CBS2950. In addition, the large reciprocal translocation affects a proline permease (PUT4) regulatory region, resulting in higher PUT4 transcript levels, which agrees with higher ethanol tolerance, improved cell growth when using proline, and higher amino acid consumption during fermentation. These results suggest that SVs are responsible for the rapid physiological adaptation of yeast to a human-related environment and demonstrate the key contribution of SVs in adaptive fermentative traits in non-model species.IMPORTANCEThe exploration of domestication signatures associated with human-related environments has predominantly focused on studies conducted on model organisms, such as Saccharomyces cerevisiae, overlooking the potential for comparisons across other non-Saccharomyces species. In our research, employing a combination of long- and short-read data, we found domestication signatures in Lachancea cidri, a non-model species recently isolated from fermentative environments in cider in France. The significance of our study lies in the identification of large array of major genomic rearrangements in a cider strain compared to wild isolates, which underly several fermentative traits. These domestication signatures result from structural variants, which are likely responsible for the phenotypic differences between strains, providing a rapid path of adaptation to human-related environments.

A special drop: Characterising yeast isolates associated with fermented beverages produced by Australia's indigenous peoples

Way-a-linah, an alcoholic beverage produced from the fermented sap of Eucalyptus gunnii, and tuba, a fermented drink made from the syrup of Cocos nucifera fructifying bud, are two of several fermented beverages produced by Australian Aboriginal and Torres Strait people. Here we describe the characterisation of yeast isolates from samples associated with the fermentation of way-a-linah and tuba. Microbial isolates were obtained from two different geographical locations in Australia - the Central Plateau in Tasmania, and Erub Island in the Torres Strait. While Hanseniaspora species and Lachancea cidri were the most abundant species in Tasmania, Candida species were the most abundant in Erub Island. Isolates were screened for tolerance to stress conditions found during the production of fermented beverages and for enzyme activities relevant to the appearance, aroma and flavour of these beverages. Based on screening results, eight isolates were evaluated for their volatile profile during the fermentation of wort, apple juice and grape juice. Diverse volatile profiles were observed for beers, ciders and wines fermented with different isolates. These findings reveal the potential of these isolates to produce fermented beverages with unique aroma and flavour profiles and highlight the vast microbial diversity associated with fermented beverages produced by Australia's Indigenous peoples.

Late Pleistocene-dated divergence between South Hemisphere populations of the non-conventional yeast L. cidri

Most organisms belonging to the Saccharomycotina subphylum have high genetic diversity and a vast repertoire of metabolisms and lifestyles. Lachancea cidri is an ideal yeast model for exploring the interplay between genetics, ecological function and evolution. Lachancea cidri diverged from the Saccharomyces lineage before the whole-genome duplication and is distributed across the South Hemisphere, displaying an important ecological success. We applied phylogenomics to investigate the genetic variation of L. cidri isolates obtained from Australia and South America. Our approach revealed the presence of two main lineages according to their geographic distribution (Aus and SoAm). Estimation of the divergence time suggests that SoAm and Aus lineages diverged near the last glacial maximum event during the Pleistocene (64-8 KYA). Interestingly, we found that the French reference strain is closely related to the Australian strains, with a recent divergence (405-51 YA), likely associated to human movements. Additionally, we identified different lineages within the South American population, revealing that Patagonia contains a similar genetic diversity comparable to that of other lineages in S. cerevisiae. These findings support the idea of a Pleistocene-dated divergence between South Hemisphere lineages, where the Nothofagus and Araucaria ecological niches likely favoured the extensive distribution of L. cidri in Patagonia.

Molecular approaches improving our understanding of Brettanomyces physiology

Brettanomyces species and particularly B. bruxellensis as the most studied representative, are strongly linked to industrial fermentation processes. This association is considered either positive or undesirable depending on the industry. While in some brewing applications and in kombucha production Brettanomyces yeasts contribute to the flavour and aroma profile of these beverages, in winemaking and bioethanol production Brettanomyces is considered a spoilage or contaminant microorganism. Nevertheless, understanding Brettanomyces biology and metabolism in detail will benefit all industries. This review discusses recent molecular biology tools including genomics, transcriptomics and genetic engineering techniques that can improve our understanding of Brettanomyces physiology and how these approaches can be used to make the industrial potential of this species a reality.

Simplified risk-prediction for benchmarking and quality improvement in emergency general surgery. Prospective, multicenter, observational cohort study

BACKGROUND AND AIMS

Emergency General Surgery (EGS) conditions account for millions of deaths worldwide, yet it is practiced without benchmarking-based quality improvement programs. The aim of this observational, prospective, multicenter, nationwide study was to determine the best benchmark cutoff points in EGS, as a reference to guide improvement measures.

METHODS

Over a 6-month period, 38 centers (5% of all public hospitals) attending EGS patients on a 24-h, 7-days a week basis, enrolled consecutive patients requiring an emergent/urgent surgical procedure. Patients were stratified into cohorts of low (i.e., expected morbidity risk <33%), middle and high risk using the novel m-LUCENTUM calculator.

RESULTS

A total of 7258 patients were included; age (mean ± SD) was 51.1 ± 21.5 years, 43.2% were female. Benchmark cutoffs in the low-risk cohort (5639 patients, 77.7% of total) were: use of laparoscopy ≥40.9%, length of hospital stays ≤3 days, any complication within 30 days ≤ 17.7%, and 30-day mortality ≤1.1%. The variables with the greatest impact were septicemia on length of hospital stay (21 days; adjusted beta coefficient 16.8; 95% CI: 15.3 to 18.3; P < .001), and respiratory failure on mortality (risk-adjusted population attributable fraction 44.6%, 95% CI 29.6 to 59.6, P < .001). Use of laparoscopy (odds ratio 0.764, 95% CI 0.678 to 0.861; P < .001), and intraoperative blood loss (101-500 mL: odds ratio 2.699, 95% CI 2.152 to 3.380; P < .001; and 500-1000 mL: odds ratio 2.875, 95% CI 1.403 to 5.858; P = .013) were associated with increased morbidity.

CONCLUSIONS

This study offers, for the first time, clinically-based benchmark values in EGS and identifies measures for improvement.

Non reducible inguinal hernias in Malawi: an occupational hazard

PURPOSE

Inguinal hernias are one of the most common surgical conditions worldwide. Due to limited surgical access in low- and middle-income countries, many hernias present emergently; however, data on the resultant outcome disparities is limited. We, therefore, sought to describe the epidemiology, clinical features, and outcomes of incarcerated inguinal hernias at a tertiary center in Malawi.

METHODS

This is a retrospective analysis of the acute care surgery registry at Kamuzu Central Hospital in Lilongwe, Malawi. All patients > 13 years admitted with a non-reducible inguinal hernia from 2013 to 2019 were included. The primary outcome was in-hospital mortality. A Poisson multivariable regression determined factors associated with increased risk of mortality.

RESULTS

A total of 297 patients presented with non-reducible inguinal hernias, the majority of which were young (median age 38), male (93.6%), farmers (47.8%). Of the 81% who underwent surgery, 55% were delayed ≥ 24 h. 19.5% of hernias were strangulated. Overall mortality was 5.4%. Increased age (RR 1.06, 95% CI 1.01-1.12), shock index ≥ 1 (RR 4.82, 95% CI 1.45-16.09), and delay ≥ 24 h from presentation to operative intervention (RR 11.24, 95% CI 1.55-81.34) resulted in an increase in relative risk of mortality.

CONCLUSION

Non-reducible inguinal hernias largely affect young male farmers in Malawi. Delays to care can limit economic productivity for this rural population, as well as, yield considerable risk of mortality. While specific patient and institutional factors must be further elucidated, increased awareness, public health prioritization, and surgical capacity building is needed to reduce further hernia-related morbidity and mortality.

Adaptive evolution of sulfite tolerance in Brettanomyces bruxellensis

Brettanomyces bruxellensis is considered one of the most problematic microbes associated with wine production. Sulfur dioxide is commonly used to inhibit the growth of B. bruxellensis and limit the potential wine spoilage. Brettanomyces bruxellensis wine isolates can grow at higher concentrations of this preservative than isolates from other sources. Thus, it has been suggested that the use of sulfite may have selected for B. bruxellensis strains better adapted to survive in the winemaking environment. We utilized laboratory adaptive evolution to determine the potential for this to occur. Three B. bruxellensis strains, representative of known genetic variation within the species, were subjected to increasing sublethal sulfur dioxide concentrations. Individual clones isolated from evolved populations displayed enhanced sulfite tolerance, ranging from 1.6 to 2.5 times higher than the corresponding parental strains. Whole-genome sequencing of sulfite-tolerant clones derived from two of the parental strains revealed structural variations affecting 270 genes. The region containing the sulfite efflux pump encoding gene, SSU1, showed clear copy number variants in all sequenced clones. Regardless of parental strain genetic background, SSU1 copy number changes were reproducibly associated with one SSU1 haplotype. This work clearly demonstrates adaptive evolution of B. bruxellensis when exposed to sublethal sulfites and suggests that, similar to Saccharomyces cerevisiae wine yeast, the mechanism responsible involves the gene SSU1.

Imaging Manifestations of Genitourinary Tuberculosis

The genitourinary region is one of the most common sites of extrapulmonary tuberculosis (TB) involvement. The imaging features of genitourinary TB are protean and can mimic other entities, including malignancy, and pose a diagnostic dilemma. Hematogenous seeding and lymphatic spread of mycobacteria from pulmonary, tonsillar, and nodal TB are implicated in the pathogenesis of genitourinary TB. In addition, contiguous extension from the urinary tract and sexual transmission are described as sources of genital TB. Genitourinary TB can be indolent and results in nonspecific signs and symptoms; thus, imaging has a vital role in the working diagnosis for these cases. Classic uroradiologic signs of genitourinary TB are primarily described from the era of intravenous urography and conventional radiography. Now, CT, CT urography, MRI, and US are used in the diagnosis and management. Familiarity with the imaging features of genitourinary TB may help guide the diagnosis and, in turn, lead to timely management. US has a vital role in the evaluation of scrotal and female genital TB. MRI offers superior soft-tissue contrast resolution and excellent depiction of anatomic detail. The various imaging manifestations of genitourinary TB are highlighted. ^©RSNA, 2021.

In vivo CD40 Silencing by siRNA Infusion in Rodents and Evaluation by Kidney Immunostaining

The co-stimulatory molecule CD40 and its ligand CD40L play a key role in the regulation of immunological processes and are involved in the pathophysiology of autoimmune and inflammatory diseases. Inhibition of the CD40-CD40L axis is a promising therapy, and a number of strategies and techniques have been designed to hinder its functionality. Our group has broad experience in silencing CD40 using RNAi technology, and here we summarize protocols for the systemic administration of a specific anti-CD40 siRNA in different rodents models, in addition to the subsequent quantification of CD40 expression in murine kidneys by immunostaining. The use of RNAi technology with specific siRNAs to silence genes is becoming an essential method to investigate gene functions and is rapidly emerging as a therapeutic tool. Graphic abstract: CD40 siRNA mechanism.

Acute Pancreatitis Imaging in MDCT: State of the Art of Usual and Unusual Local Complications. 2012 Atlanta Classification Revisited

Acute pancreatitis is an inflammatory disease in which most common etiologies are biliary lithiasis and alcoholism. Acute pancreatitis can be classified into 2 groups according to its morphologic features: interstitial edematous pancreatitis and necrotizing acute pancreatitis. The prognosis of this group of diseases and its complications varies significantly and contrast-enhanced computed tomography is the imaging study of choice for the diagnosis and detection of complications. . In this review, we aim to summarize the changes introduced in the revised Atlanta classification and describe other usual and unusual local complications of acute pancreatitis that are not analyzed in that classification. We will also describe early detection signs and provide an accurate interpretation of complications on contrast-enhanced computed tomography that will lead to prompt management decisions which can reduce the morbidity and mortality of these patients.

Identification of flocculant wine yeast strains with improved filtration-related phenotypes through application of high-throughput sedimentation rate assays

In most yeast-driven biotechnological applications, biomass is separated from the aqueous phase after fermentation or production has finished. During winemaking, yeasts are removed after fermentation by racking, filtration, or centrifugation, which add costs to the overall process and may reduce product yield. Theoretically, clarification and filtration can be aided through use of yeast strains that form flocs due to cell-cell binding, a process known as flocculation. However, because early flocculation can cause stuck/sluggish fermentations, this phenotype is not common amongst commercially available wine yeasts. In this study we sought to identify wine strains that exhibit late-fermentation flocculant behaviour using two complementary approaches; a high-throughput sedimentation rate assay of individual strains and a competitive sedimentation assay using a barcoded yeast collection. Amongst 103 wine strains, several exhibited strong sedimentation at the end of the wine fermentation process under various environmental conditions. Two of these strains, AWRI1688 and AWRI1759, were further characterised during red winemaking trials. Shiraz wines produced with both strains displayed improved filtration-related properties. AWRI1759 produced wines with greater filterability, whereas AWRI1688 enabled the recovery of larger wine volumes after racking. Thus, this study demonstrates the effective use of sedimentation screening assays to identify wine yeasts with practical winemaking applications.

The double edge of anti-CD40 siRNA therapy: It increases renal microcapillar density but favours the generation of an inflammatory milieu in the kidneys of ApoE -/- mice

Background

Chronic kidney disease (CKD) is associated with endothelial dysfunctions thus prompting links between microcirculation (MC), inflammation and major cardiovascular risk factors.

Purpose of the study

We have previously reported that siRNA-silencing of CD40 (siCD40) reduced atherosclerosis (ATH) progression. Here, we have deepened on the effects of the siCD40 treatment by evaluating retrospectively, in stored kidneys from the siCD40 treated ApoE^−/− mice, the renal microcirculation (measured as the density of peritubular capillaries), macrophage infiltration and NF-κB activation.

Methods

Kidneys were isolated after 16 weeks of treatment with the anti-CD40 siRNA (siCD40), with a scrambled control siRNA (siSC) or with PBS (Veh. group). Renal endothelium, infiltrating macrophages and activated NF-κB in endothelium were identified by immunohistochemistry, while the density of stained peritubular capillaries was quantified by image analysis.

Results

ATH was associated with a reduction in renal MC, an effect reversed by the anti-CD40 siRNA treatment (3.8 ± 2.7% in siCD40; vs. 1.8 ± 0.1% in siSC; or 1.9 ± 1.6% in Veh.; p < 0.0001). Furthermore, siCD40 treatment reduced the number of infiltrating macrophages compared to the SC group (14.1 ± 5.9 cells/field in siCD40; vs. 37.1 ± 17.8 cells/field in siSC; and 1.3 ± 1.7 cells/field in Veh.; p = 0.001). NF-κB activation also peaked in the siSC group, showing lower levels in the siCD40 and Veh. groups (63 ± 60 positive cells/section in siCD40; vs. 152 ± 44 positive cells/section in siSC; or 26 ± 29 positive cells/section in veh.; p = 0.014). Lastly, serum creatinine was also increased in the siCD40 (3.4 ± 3.3 mg/dL) and siSC (4.6 ± 3.0 mg/dL) groups when compared with Veh. (1.1 ± 0.9 mg/dL, p = 0.1).

Conclusions

Anti-CD40 siRNA therapy significantly increased the density of peritubular capillaries and decreased renal inflammation in the ATH model. These data provide a physiological basis for the development of renal diseases in patients with ATH. Furthermore, our results also highligth renal off-target effects of the siRNA treatment which are discussed.

Graphical abstract

Volatile profile of reduced alcohol wines fermented with selected non-Saccharomyces yeasts under different aeration conditions

Over the last decades there has been an increase in ethanol concentration in wine. High ethanol concentration may impact negatively wine flavor and can be associated with harmful effects on human health. In this study, we investigated a microbiological approach to reduce wine ethanol concentration, using three non-Saccharomyces yeast strains (Metschnikowia pulcherrima, Torulaspora delbrueckii and Zygosaccharomyces bailii) in sequential fermentations with S. cerevisiae under different aeration conditions. At the same time, we evaluated the volatile profile of the resulting reduced alcohol Chardonnay wines. Results showed that the non-Saccharomyces yeasts tested were able to reduce wine ethanol concentration when oxygen was provided. Compared to S. cerevisiae wines, ethanol reduction was 1.6% v/v, 0.9% v/v and 1.0% v/v for M. pulcherrima, T. delbrueckii and Z. bailii sequential fermentations, respectively. Under the conditions evaluated here, aeration did not affect acetic acid production for any of the non-Saccharomyces strains tested. Although aeration affected wine volatile profiles, this was depended on yeast strain. Thus, wines produced with M. pulcherrima under aeration of 0.05 volume of air per volume of culture per minute (VVM) showed excessive ethyl acetate content, while Z. bailli wines produced with 0.05 VVM aeration had increased concentrations of higher alcohols and volatile acids. Increased concentrations of these compounds over their sensory thresholds, are likely to impact negatively on wine sensory profile. Contrarily, all three non-Saccharomyces strains under 0.025 VVM aeration conditions produced wines with reduced ethanol concentration and acceptable chemical volatile profiles.

Development of a genetic transformation toolkit for Brettanomyces bruxellensis

Brettanomyces bruxellensis is usually considered a spoilage microorganism, responsible for significant economic losses during the production of fermented beverages such as wine, beer and cider, though for some styles of beer its influence is essential. In recent years, the competitiveness of this yeast in bioethanol production processes has brought to attention its broader biotechnological potential. Furthermore, the species has evolved key fermentation traits in parallel with Saccharomyces cerevisiae. Attempts to better understand B. bruxellensis physiology through genomics-driven research have been hampered by a lack of functional genomics tools. Genetic transformation for B. bruxellensis has only been developed recently and with limited efficiency. Here we describe gene transformation cassettes tailored for B. bruxellensis, which provide multiple drug-resistant markers and the ability to tag B. bruxellensis with different fluorescent proteins. All marker cassettes resulted in increased transformation efficiency compared to the maximum reported in literature, with one cassette, TDH1p natMX, showing five times greater efficiency. Transformation cassettes encoding fluorescent proteins enabled discrimination between subpopulations of transformed B. bruxellensis cells by flow cytometry and fluorescent microscopy. Thus, the genetic transformation toolkit described here unlocks several molecular applications such as strain tagging, insertional mutagenesis and potentially targeted gene deletion.

Laboratory exposure to Coccidioides: lessons learnt in a non-endemic country

Coccidioides is a primary pathogenic fungus, which infects humans through highly infectious arthroconidia, causing substantial morbidity including life-threatening disseminated infections. Due to the low infectious dose, laboratory personnel might become infected during diagnostic procedures. Accordingly, coccidioidomycosis is reported as the most frequent laboratory-acquired systemic mycosis worldwide. This risk is aggravated in non-endemic countries, where the diagnosis may not be suspected. We report on an inadvertent exposure of 44 persons to Coccidioides posadasii in a clinical microbiology laboratory in Chile, the measures of containment after rapid diagnosis with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and the lessons learnt in a non-endemic setting.

Competition experiments between Brettanomyces bruxellensis strains reveal specific adaptation to sulfur dioxide and complex interactions at intraspecies level

Recent studies have suggested a strong niche adaptation for Brettanomyces bruxellensis strains according to human-related fermentation environments, including beer, wine and bioethanol. This is further supported by a correlation between B. bruxellensis genetic grouping and tolerance to SO2, the main antimicrobial used in wine. The allotriploid AWRI1499-like cluster, in particular, shows high SO2 tolerance suggesting that the genetic configuration observed for these strains may confer a selective advantage in winemaking conditions. To test this hypothesis, we evaluated the relative selective advantage of representatives of the three main B. bruxellensis genetic groups in presence of SO2. As a proof-of-concept and using recently developed transformation cassettes, we compared strains under different SO2 concentrations using pairwise competitive fitness experiments. Our results showed that AWRI1499 is specifically adapted to environments with high SO2 concentrations compared to other B. bruxellensis wine strains, indicating a potential correlation between allotriploidisation origin and environmental adaptation in this species. Additionally, our findings suggest different types of competition between strains, such as coexistence and exclusion, revealing new insights on B. bruxellensis interactions at intraspecies level.

Microbiological strategies to produce beer and wine with reduced ethanol concentration

Changes in consumer preferences, government policies and environmental conditions have driven research efforts towards producing alcoholic beverages with reduced alcohol content, namely wine and beer. While the strategies available to accomplish this goal vary for wine and beer, a common approach relies on the use of yeast strains which are less efficient at producing ethanol. Here we discuss current research on the isolation and/or generation of yeast strains able to produce beer or wine with reduced ethanol concentration. Particular consideration is given to the impact of 'low-ethanol' yeasts on volatile composition and sensory profile of beer and wine.

Sensory profile and volatile aroma composition of reduced alcohol Merlot wines fermented with Metschnikowia pulcherrima and Saccharomyces uvarum

Strategies for production of wines containing lower alcohol concentrations are in strong demand, for reasons of quality, health, and taxation. Development and application of wine yeasts that are less efficient at transforming grape sugars into ethanol has the potential to allow winemakers the freedom to make lower alcohol wines from grapes harvested at optimal ripeness, without the need for post-fermentation processes aimed at removing ethanol. We have recently shown that two non-conventional wine yeast species Metschnikowia pulcherrima and Saccharomyces uvarum were both able to produce wine with reduced alcohol concentration. Both species produced laboratory-scale wines with markedly different volatile aroma compound composition relative to Saccharomyces cerevisiae. This work describes the volatile composition and sensory profiles of reduced-alcohol pilot-scale Merlot wines produced with M. pulcherrima and S. uvarum. Wines fermented with M. pulcherrima contained 1.0% v/v less ethanol than S. cerevisiae fermented wines, while those fermented with S. uvarum showed a 1.7% v/v reduction in ethanol. Compared to S. cerevisiae ferments, wines produced with M. pulcherrima showed higher concentrations of ethyl acetate, total esters, total higher alcohols and total sulfur compounds, while wines fermented with S. uvarum were characterised by the highest total concentration of higher alcohols. Sensorially, M. pulcherrima wines received relatively high scores for sensory descriptors such as red fruit and fruit flavour and overall exhibited a sensory profile similar to that of wine made with S. cerevisiae, whereas the main sensory descriptors associated with wines fermented with S. uvarum were barnyard and meat. This work demonstrates the successful application of M. pulcherrima AWRI3050 for the production of pilot-scale red wines with reduced alcohol concentration and highlights the need for rigorous evaluation of non-conventional yeasts with regard to their sensory impacts.

Yeast's balancing act between ethanol and glycerol production in low-alcohol wines

Alcohol is fundamental to the character of wine, yet too much can put a wine off‐balance. A wine is regarded to be well balanced if its alcoholic strength, acidity, sweetness, fruitiness and tannin structure complement each other so that no single component dominates on the palate. Balancing a wine's positive fruit flavours with the optimal absolute and relative concentration of alcohol can be surprisingly difficult. Over the past three decades, consumers have increasingly demanded wine with richer and riper fruit flavour profiles. In response, grape and wine producers have extended harvest times to increase grape maturity and enhance the degree of fruit flavours and colour intensity. However, a higher degree of grape maturity results in increased grape sugar concentration, which in turn results in wines with elevated alcohol concentration. On average, the alcohol strength of red wines from many warm wine‐producing regions globally rose by about 2% (v/v) during this period. Notwithstanding that many of these ‘full‐bodied, fruit‐forward’ wines are well balanced and sought after, there is also a significant consumer market segment that seeks lighter styles with less ethanol‐derived ‘hotness’ on the palate. Consumer‐focussed wine producers are developing and implementing several strategies in the vineyard and winery to reduce the alcohol concentration in wines produced from well‐ripened grapes. In this context, Saccharomyces cerevisiae wine yeasts have proven to be a pivotal strategy to reduce ethanol formation during the fermentation of grape musts with high sugar content (> 240 g l⁻¹). One of the approaches has been to develop ‘low‐alcohol’ yeast strains which work by redirecting their carbon metabolism away from ethanol production to other metabolites, such as glycerol. This article reviews the current challenges of producing glycerol at the expense of ethanol. It also casts new light on yeast strain development programmes which, bolstered by synthetic genomics, could potentially overcome these challenges.

Meta-analysis and adjusted indirect comparison of direct oral anticoagulants in prevention of acute limb ischemia in patients with atrial fibrillation

BACKGROUND

Direct oral anticoagulants are being presented as alternatives to warfarin for preventing stroke in patients with atrial fibrillation. Yet direct comparative trials between these agents in prevention of acute limb ischemia (ALI) are unavailable so far.

OBJECTIVE

To conduct an adjusted indirect comparison meta-analysis between direct oral agents for prevention of acute limb ischemia in atrial fibrillation.

METHODS

We conducted a systematic literature review searching electronic databases (MEDLINE and Embase) and the Cochrane Library from January 1990 through November 2014. Two blinded investigators reviewed all potentially relevant articles in a parallel manner by using a priori defined criteria. To assess the long-term efficacy and safety of these agents, only randomized clinical trials (RCTs) with follow-up durations of >1 year were included. The primary efficacy outcome was the end point of acute limb ischemia and/or extremity embolism.

RESULTS

A total of 44,563 patients from three RCTs met criteria for inclusion. Patients randomized to direct oral anticoagulants had a non-significant decreased risk for acute limb ischemia (risk ratio [RR]: 0.57, 95% confidence interval [CI]: 0.26-1.2). In the analysis between agents, however, rivaroxaban significantly lowered the risk of ALI compared to warfarin (RR: 0.23, 95% CI: 0.064-0.82), apixaban (RR: 0.26, 95% CI: 0.081-0.83), and dabigatran (RR: 0.24, 95% CI: 0.077-0.83).

CONCLUSIONS

Significant differences in prevention of acute limb ischemia may exist between oral anticoagulant agents in patients with atrial fibrillation. Rivaroxaban lowers the risk of limb embolism versus warfarin, apixaban and dabigatran.

Progress in the development of small molecules as new human A3 adenosine receptor ligands based on the 3-thiophenylcoumarin core

3-Thiophenylcoumarins are described as adenosine receptor ligands. Synthesis, in vitro pharmacological assays and docking studies were performed.

Mycolic acids: deciphering and targeting the Achilles' heel of the tubercle bacillus

Mycolic acids are unique long chain fatty acids found in the lipid-rich cell walls of mycobacteria including the tubercle bacillus Mycobacterium tuberculosis. Essential for viability and virulence, enzymes involved in the biosynthesis of mycolic acids represent novel targets for drug development. This is particularly relevant to the impact on global health given the rise of multidrug resistant and extensively drug resistant strains of M. tuberculosis. In this review, we discuss recent advances in our understanding of how mycolic acid are synthesised, especially the potential role of specialised fatty acid synthase complexes. Also, we examine the role of a recently reported mycolic acid transporter MmpL3 with reference to several reports of the targeting of this transporter by diverse compounds with anti-M. tuberculosis activity. Additionally, we consider recent findings that place mycolic acid biosynthesis in the context of the cell biology of the bacterium, viz its localisation and co-ordination with the bacterial cytoskeleton, and its role beyond maintaining cell envelope integrity.

The application of non-Saccharomyces yeast in fermentations with limited aeration as a strategy for the production of wine with reduced alcohol content

High alcohol concentrations reduce the complexity of wine sensory properties. In addition, health and economic drivers have the wine industry actively seeking technologies that facilitate the production of wines with lower alcohol content. One of the simplest approaches to achieve this aim would be the use of wine yeast strains which are less efficient at transforming grape sugars into ethanol, however commercially available wine yeasts produce very similar ethanol yields. Non-conventional yeast, in particular non-Saccharomyces species, have shown potential for producing wines with lower alcohol content. These yeasts are naturally present in the early stages of fermentation but in general are not capable of completing alcoholic fermentation. We have evaluated 48 non-Saccharomyces isolates to identify strains that, with limited aeration and in sequential inoculation regimes with S. cerevisiae, could be used for the production of wine with lower ethanol concentration. Two of these, Torulaspora delbrueckii AWRI1152 and Zygosaccharomyces bailii AWRI1578, enabled the production of wine with reduced ethanol concentration under limited aerobic conditions. Depending on the aeration regime T. delbrueckii AWRI1152 and Z. bailii AWRI1578 showed a reduction in ethanol concentration of 1.5% (v/v) and 2.0% (v/v) respectively, compared to the S. cerevisiae anaerobic control.

Design and discovery of tyrosinase inhibitors based on a coumarin scaffold

A novel series of 3-aryl and 3-heteroarylcoumarins displaying tyrosinase inhibitory activity.

Anatomical substrates for direct interactions between hippocampus, medial prefrontal cortex, and the thalamic nucleus reuniens

The reuniens nucleus in the midline thalamus projects to the medial prefrontal cortex (mPFC) and the hippocampus, and has been suggested to modulate interactions between these regions, such as spindle-ripple correlations during sleep and theta band coherence during exploratory behavior. Feedback from the hippocampus to the nucleus reuniens has received less attention but has the potential to influence thalamocortical networks as a function of hippocampal activation. We used the retrograde tracer cholera toxin B conjugated to two fluorophores to study thalamic projections to the dorsal and ventral hippocampus and to the prelimbic and infralimbic subregions of mPFC. We also examined the feedback connections from the hippocampus to reuniens. The goal was to evaluate the anatomical basis for direct coordination between reuniens, mPFC, and hippocampus by looking for double-labeled cells in reuniens and hippocampus. In confirmation of previous reports, the nucleus reuniens was the origin of most thalamic afferents to the dorsal hippocampus, whereas both reuniens and the lateral dorsal nucleus projected to ventral hippocampus. Feedback from hippocampus to reuniens originated primarily in the dorsal and ventral subiculum. Thalamic cells with collaterals to mPFC and hippocampus were found in reuniens, across its anteroposterior axis, and represented, on average, about 8 % of the labeled cells in reuniens. Hippocampal cells with collaterals to mPFC and reuniens were less common (~1 % of the labeled subicular cells), and located in the molecular layer of the subiculum. The results indicate that a subset of reuniens cells can directly coordinate activity in mPFC and hippocampus. Cells with collaterals in the hippocampus-reuniens-mPFC network may be important for the systems consolidation of memory traces and for theta synchronization during exploratory behavior.

Genetic engineering of industrial Saccharomyces cerevisiae strains using a selection/counter-selection approach

Gene modification of laboratory yeast strains is currently a very straightforward task thanks to the availability of the entire yeast genome sequence and the high frequency with which yeast can incorporate exogenous DNA into its genome. Unfortunately, laboratory strains do not perform well in industrial settings, indicating the need for strategies to modify industrial strains to enable strain development for industrial applications. Here we describe approaches we have used to genetically modify industrial strains used in winemaking.

Toxins from Physalia physalis (Cnidaria) raise the intracellular Ca(2+) of beta-cells and promote insulin secretion

Physalia physalis is a marine cnidarian from which high molecular weight toxins with hemolytic and neurotoxic effects have been isolated. In the present work, two novel toxins, PpV9.4 and PpV19.3 were purified from P. physalis by bioactive guideline isolation. It involved two steps of column chromatography, gel filtration and RP-HPLC. The molecular weights were 550.7 and 4720.9 Da for PpV9.4 and PpV19.3, respectively. In the light of the Edman sequencing results, the structure of these toxins included the presence of modified amino acids. Both toxins increased the percentage of insulin secreting beta-cells and induced cytosolic Ca2+ elevation. To date, this is the first report of low molecular weight toxins increasing insulin secretion purified from cnidarians, by constituting a new approach to the study of beta-cells physiology.

The gating of neocortical information by modulators

Thalamic input to the neocortex is crucial for sensory perception and constitutes the basis of complex awake behavior. Connections within the neocortex play an important role in internally generated neural activity, which is considered critical for memory retrieval and for the generation of imagery in our dreams. Modulatory neurotransmitters, such as noradrenaline and acetylcholine, gate information transmission in the brain. Favero et al. (J Neurophysiol 108: 1010-1024, 2012) show that modulators differentially facilitate thalamocortical relative to intracortical transmission in the input layers of cortex.

Flavour-active wine yeasts

The flavour of fermented beverages such as beer, cider, saké and wine owe much to the primary fermentation yeast used in their production, Saccharomyces cerevisiae. Where once the role of yeast in fermented beverage flavour was thought to be limited to a small number of volatile esters and higher alcohols, the discovery that wine yeast release highly potent sulfur compounds from non-volatile precursors found in grapes has driven researchers to look more closely at how choice of yeast can influence wine style. This review explores recent progress towards understanding the range of ‘flavour phenotypes’ that wine yeast exhibit, and how this knowledge has been used to develop novel flavour-active yeasts. In addition, emerging opportunities to augment these phenotypes by engineering yeast to produce so-called grape varietal compounds, such as monoterpenoids, will be discussed.

MmpL genes are associated with mycolic acid metabolism in mycobacteria and corynebacteria

Mycolic acids are vital components of the cell wall of the tubercle bacillus Mycobacterium tuberculosis and are required for viability and virulence. While mycolic acid biosynthesis is studied extensively, components involved in mycolate transport remain unidentified. We investigated the role of large membrane proteins encoded by mmpL genes in mycolic acid transport in mycobacteria and the related corynebacteria. MmpL3 was found to be essential in mycobacteria and conditional depletion of MmpL3 in Mycobacterium smegmatis resulted in loss of cell wall mycolylation, and of the cell wall-associated glycolipid, trehalose dimycolate. In parallel, an accumulation of trehalose monomycolate (TMM) was observed, suggesting that mycolic acids were transported as TMM. In contrast to mycobacteria, we found redundancy in the role of two mmpL genes, in Corynebacterium glutamicum; a complete loss of trehalose-associated and cell wall bound corynomycolates was observed in an NCgl0228-NCgl2769 double mutant, but not in individual single mutants. Our studies highlight the role of mmpL genes in mycolic acid metabolism and identify potential new targets for anti-TB drug development.

Effect of oxygen and lipid supplementation on the volatile composition of chemically defined medium and Chardonnay wine fermented with Saccharomyces cerevisiae

Oxygen or lipids are required to complete stressful alcoholic fermentation. Lack of these nutrients can inhibit sugar uptake and growth, which leads to incomplete or 'stuck' fermentation. Oxygen or lipids supplementation not only restores yeast fermentative activity and also affects formation of yeast volatile metabolites. To clarify the effect of oxygen and lipid supplementation on the formation of flavour active metabolites during wine fermentation, we evaluated the addition of these two nutrients to chemically defined grape juice and filter clarified Chardonnay must. Lipid addition increased the concentration of esters, higher alcohols and volatile acids, whereas oxygen increased the concentration of higher alcohols and altered the proportion of acetate to ethyl esters and the proportion of branch-chain acids to medium-chain fatty acids. Combined addition of lipids and oxygen showed an additive effect on concentration of higher alcohols whereas oxygen suppressed the enhancing effect of lipids on formation of esters and volatile acids. Our results demonstrate the potential of lipid and oxygen supplementation for the manipulation of wine aroma in white wine fermentation.

Analysis of vascular endothelial growth factor gene expression in the tissues of patients with chronic venous insufficiency

OBJECTIVE

Immunohistochemical techniques have revealed the presence of vascular endothelial growth factor (VEGF) in the epidermis of patients with chronic venous disease (CVD). Our objective was to perform a quantitative analysis of the VEGF gene transcription in tissues that are potential sources of this factor (skin, varicose veins [VV] and great saphenous vein [GSV]) in patients with CVD.

METHODS

In all, 212 skin and venous tissue samples were collected from patients diagnosed with CVD and controls. The VEGF gene expression was analysed using quantitative realtime polymerase chain reaction (PCR).

RESULTS

The skin VEGF expression was lower in the CVD group than in the control group (P = 0.04). There were no significant differences between the insufficient GSV of the CVD group and the control healthy vein (P = 0.22). There was a greater expression of VEGF in the VV of the CVD group than in the control healthy vein (P = 0.03). Comparison of the VEGF expression between the different tissue types in the CVD group revealed significant differences between the skin and GSV (P = 0.02) and between the skin and the VV (P = 0.004), and between the VV and the GSV (P = 0.02).

CONCLUSIONS

The results of the present study show an over-expression of VEGF gene in the VV tissue of patients with CVD. Based on the data in patients with C2 disease, the VVs appear to be the source of increased VEGF expression.