Genetic Variant of DNAM-1 rs763361 C>T Is Associated with Ankylosing Spondylitis in a Mexican Population.

DNAM-1 (CD226) is an activating receptor expressed in CD8+ T cells, NK cells, and monocytes. It has been reported that two SNPs in the DNAM-1 gene, rs763361 C>T and rs727088 G>A, have been associated with different autoimmune diseases; however, the role of DNAM-1 in ankylosing spondylitis has been less studied. For this reason, we focused on the study of these two SNPs in association with ankylosing spondylitis. For this, 34 patients and 70 controls were analyzed using endpoint PCR with allele-specific primers. Our results suggest that rs763361 C>T is involved as a possible protective factor under the CT co-dominant model (OR = 0.34, 95% CI = 0.13-0.88, p = 0.022) and the CT + TT dominant model (OR = 0.39, 95% CI = 0.17-0.90, p = 0.025), while rs727088 G>A did not show an association with the disease in any of the inheritance models. When analyzing the relationships of the haplotypes, we found that the T + A haplotype (OR = 0.31, 95% CI = 0.13-0.73, p = 0.0083) is a protective factor for developing the disease. In conclusion, the CT and CT + TT variants of rs763361 C>T and the T + A haplotype were considered as protective factors for developing ankylosing spondylitis.

Profound Defect of Amphiregulin Secretion by Regulatory T Cells in the Gut of HIV-Treated Patients.

The persistence of a leaky gut in HIV-treated patients leads to chronic inflammation with increased rates of cardiovascular, liver, kidney, and neurological diseases. Tissue regulatory T (tTreg) cells are involved in the maintenance of intestinal homeostasis and wound repair through the IL-33 pathway. In this study, we investigated whether the persistence of gut mucosal injury during HIV infection might be explained in part by a flaw in the mechanisms involved in tissue repair. We observed an increased level of IL-33 in the gut of HIV-infected patients, which is associated with an increased level of fibrosis and a low peripheral reconstitution of CD4+ T cells. Our results showed that intestinal Treg cells from HIV-infected patients were enriched in tTreg cells prone to support tissue repair. However, we observed a functional defect in tTreg cells caused by the lack of amphiregulin secretion, which could contribute to the maintenance of intestinal damage. Our data suggest a mechanism by which the lack of amphiregulin secretion by tTreg may contribute to the lack of repair of the epithelial barrier.

In vitro Acaricidal Activity of Serratia Ureilytica Against the Dust Mite Tyrophagus Putrescentiae and Identification of Genes Related to Biocontrol.

The present study evaluated the acaricidal activity of three Serratia strains isolated from Mimosa pudica nodules in the Lancandon zone Chiapas, Mexico. The analysis of the genomes based on the Average Nucleotide Identity, the phylogenetic relationships allows the isolates to be placed in the Serria ureilytica clade. The size of the genomes of the three strains is 5.4 Mb, with a GC content of 59%. The Serratia UTS2 strain presented the highest mortality with 61.41% against Tyrophagus putrescentiae followed by the Serratia UTS4 strain with 52.66% and Serratia UTS3 with 47.69% at 72 h at a concentration of 1X109 cell/mL. In the bioinformatic analysis of the genomes, genes related to the synthesis of chitinases, proteases and cellulases were identified, which have been reported for the biocontrol of mites. It is the first report of S. ureilytica with acaricidal activity, which may be an alternative for the biocontrol of stored products with high fat and protein content.

Decrease in platelet count in patients with AKI and its association with major adverse kidney events.

INTRODUCTION: A reduction in platelet count in critically ill patients is a marker of severity of the clinical condition. However, whether this association holds true in acute kidney injury (AKI) is unknown. We analyzed the association between platelet reduction in patients with AKI and major adverse kidney events (MAKE). METHODS: In this retrospective cohort, we included AKI patients at the Hospital Civil of Guadalajara, in Jalisco, Mexico. Patients were divided according to whether their platelet count fell >21% during the first 10 days. Our objectives were to analyze the associations between a platelet reduction >21% and MAKE at 10 days (MAKE10) or at 30-90 days (MAKE30-90) and death. RESULTS: From 2017 to 2023, 400 AKI patients were included, 134 of whom had a > 21% reduction in platelet count. The mean age was 54 years, 60% were male, and 44% had sepsis. The mean baseline platelet count was 194 x 103 cells/µL, and 65% of the KDIGO3 patients met these criteria. Those who underwent hemodialysis (HD) had lower platelet counts. After multiple adjustments, a platelet reduction >21% was associated with MAKE10 (OR 4.2, CI 2.1-8.5) but not with MAKE30-90. The mortality risk increased 3-fold (OR 2.9, CI 1.1-7.7, p = 0.02) with a greater decrease in the platelets (<90 x 103 cells/µL). As the platelets decreased, the incidence of MAKE was more likely to increase. These associations lost significance when accounting for starting HD. CONCLUSION: In our retrospective cohort of patients with AKI, a > 21% reduction in platelet count was associated with MAKE. Our results are useful for generating hypotheses and motivating us to continue studying this association with a more robust design.

A reduction in platelet count in critically ill patients has been associated with a worse prognosis, but it is not yet known whether this relationship also exists in patients with acute kidney injury, who are more susceptible to platelet decrease due to the syndrome or due to the onset of hemodialysis. In our study of acute kidney injury patients, we found that those whose platelet count decreased >21% during the first days were more likely to experience a major kidney event. In addition, the greater the decrease in platelet count was, the more likely these events were to occur. The significance of this association was lost in patients who start hemodialysis. Our conclusions could serve to generate hypotheses about this interesting relationship.

Systolic Blood Pressure and the Risk of Kidney Replacement Therapy and Mortality in Patients with Chronic Kidney Disease Stages 4-5.

INTRODUCTION: In patients with chronic kidney disease stages 4 and 5 (CKD stages 4-5) without dialysis and arterial hypertension, it is unknown if the values of systolic blood pressure (SBP) considered in control (<120 mm Hg) are associated with kidney replacement therapy (KRT) and mortality. METHODS: In this retrospective cohort study, hypertensive CKD stages 4-5 patients attending the Renal Health Clinic at the Hospital Civil de Guadalajara were enrolled. We divided them into those that achieved SBP <120 mm Hg (controlled group) and those who did not (>120 mm Hg), the uncontrolled group. Our primary objective was to analyze the association between the controlled group and KRT; the secondary objective was the mortality risk and if there were subgroups of patients that achieved more benefit. Data were analyzed using Stata software, version 15.1. RESULTS: During 2017-2022, a total of 275 hypertensive CKD stages 4-5 patients met the inclusion criteria for the analysis: 62 in the controlled group and 213 in the uncontrolled group; mean age 61 years; 49.82% were male; SBP was significantly lower in the controlled group (111 mm Hg) compared to the uncontrolled group (140 mm Hg); eGFR was similar between groups (20.41 mL/min/1.73 m2). There was a tendency to increase the mortality risk in the uncontrolled group (HR 6.47 [0.78-53.27]; p = 0.082) and an association by the Kaplan-Meir analysis (Log-rank p = 0.043). The subgroup analysis for risk of KRT in the controlled group revealed that patients ≥61 years had a lower risk of KRT (HR 0.87 [95% CI, 0-76-0.99]; p = 0.03, p of interaction = 0.005), but no differences were found in the subgroup analysis for mortality. In a follow-up of 1.34 years, no association was found in the risk of KRT according to the controlled or uncontrolled groups in a multivariate Cox analysis. CONCLUSION: In a retrospective cohort of patients with CKD stages 4-5 and hypertension, SBP >120 mm Hg was not associated with risk of KRT but could be associated with the risk of death. Clinical trials are required in this group of patients to demonstrate the impact of reaching the SBP goals recommended by the KDIGO guidelines.

Corrigendum: CD32a is a marker of a CD4 T-cell HIV reservoir harbouring replication-competent proviruses.

This corrects the article DOI: 10.1038/nature21710.

CD32a is a marker of a CD4 T-cell HIV reservoir harbouring replication-competent proviruses.

The persistence of the HIV reservoir in infected individuals is a major obstacle to the development of a cure for HIV. Here, using an in vitro model of HIV-infected quiescent CD4 T cells, we reveal a gene expression signature of 103 upregulated genes that are specific for latently infected cells, including genes for 16 transmembrane proteins. In vitro screening for surface expression in HIV-infected quiescent CD4 T cells shows that the low-affinity receptor for the immunoglobulin G Fc fragment, CD32a, is the most highly induced, with no detectable expression in bystander cells. Notably, productive HIV-1 infection of T-cell-receptor-stimulated CD4 T cells is not associated with CD32a expression, suggesting that a quiescence-dependent mechanism is required for its induction. Using blood samples from HIV-1-positive participants receiving suppressive antiretroviral therapy, we identify a subpopulation of 0.012% of CD4 T cells that express CD32a and host up to three copies of HIV DNA per cell. This CD32a+ reservoir was highly enriched in inducible replication-competent proviruses and can be predominant in some participants. Our discovery that CD32a+ lymphocytes represent the elusive HIV-1 reservoir may lead to insights that will facilitate the specific targeting and elimination of this reservoir.

Determinants and Trends of the Use of Intravenous Thrombolysis for Minor Stroke: A Population-Based Study, 2016 to 2020.

BACKGROUND: We analyzed the main factors associated with intravenous thrombolysis (IVT) in patients with minor ischemic stroke. METHODS: Data were obtained from a prospective, government-mandated, population-based registry of stroke code patients in Catalonia (6 Comprehensive Stroke Centers, 8 Primary Stroke Centers, and 14 TeleStroke Centers). We selected patients diagnosed with ischemic stroke and National Institutes of Health Stroke Scale (NIHSS) ≤5 at hospital admission from January 2016 to December 2020. We excluded patients with a baseline modified Rankin Scale score of ≥3, absolute contraindication for IVT, unknown stroke onset, or admitted to hospital beyond 4.5 after stroke onset. The main outcome was treatment with IVT. We performed univariable and binary logistic regression analyses to identify the most important factors associated with IVT. RESULTS: We included 2975 code strokes; 1433 (48.2%) received IVT of which 30 (2.1%) had a symptomatic hemorrhagic transformation. Patients treated with IVT as compared to patients who did not receive IVT were more frequently women, had higher NIHSS, arrived earlier to hospital, were admitted to a Comprehensive Stroke Centers, and had large vessel occlusion. After binary logistic regression, NIHSS score 4 to 5 (odds ratio, 40.62 [95% CI, 31.73-57.22]; P<0.001) and large vessel occlusion (odds ratio, 16.39 [95% CI, 7.25-37.04]; P<0.001) were the strongest predictors of IVT. Younger age, female sex, baseline modified Rankin Scale score of 0, earlier arrival to hospital (<120 minutes after stroke onset), and the type of stroke center were also independently associated with IVT. The weight of large vessel occlusion on IVT was higher in patients with lower NIHSS. CONCLUSIONS: Minor stroke female patients, with higher NIHSS, arriving earlier to the hospital, presenting with large vessel occlusion and admitted to a Comprehensive Stroke Centers were more likely to receive intravenous thrombolysis.

Deleted genes associated with obesity in Mexican patients diagnosed with nonalcoholic fatty liver disease.

AIM: Nonalcoholic fatty liver disease (NAFLD) is a complex metabolic condition in which both lifestyle and genetic factors have a pathogenic role. The LEP gene encodes leptin, which regulates appetite, body weight, and several metabolic functions. Proopiomelanocortin (POMC), regulates food intake and energy balance. The aim of the study was to determine partial or complete deletions of genes associated with obesity in patients diagnosed with NAFLD. MATERIAL AND METHODS: Blood samples and DNA from 43 individuals diagnosed with NAFLD by ultrasonographic technique (Fibroscan) were obtained. The partial or complete deletions of genes were determined by MLPA (Multiplex Ligation-dependent Probe Amplification) using the SALSA probemix P220-B2 Obesity only on 43 individuals. Fifty blood samples from healthy individuals were included. RESULTS: Eleven out of 43 individuals analyzed by MLPA presented some deletion of the genes analyzed: six were female and five were male. The partial or complete deletion of the LEPR and POMC genes was observed in eight patients (18.6%), SIM1 in six patients (13.9%), GRIK2 and SH2B1 in two patients (4.7%), SEZGL2 in four patients (9.3%), and MCR4 in one patient (2.3%). CONCLUSION: Partial deletion was observed in LEPR, POMC, SIM1, GRIK2, SH2B1, SEZGL2, and MCR4 genes in 26% of the cases, and we suggest that these alterations probably has a potential relationship for the development of NAFLD.

Atherosclerotic Cardiovascular Events in Patients Infected With Human Immunodeficiency Virus and Hepatitis C Virus.

BACKGROUND: An increased risk of cardiovascular disease (CVD) was reported in patients coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV), without identifying factors associated with atherosclerotic CVD (ASCVD) events. METHODS: HIV-HCV coinfected patients were enrolled in the Agence Nationale de Recherches sur le Sida et les hépatites virales (ANRS) CO13 HEPAVIH nationwide cohort. Primary outcome was total ASCVD events. Secondary outcomes were coronary and/or cerebral ASCVD events, and peripheral artery disease (PAD) ASCVD events. Incidences were estimated using the Aalen-Johansen method. Factors associated with ASCVD were identified using cause-specific Cox proportional hazards models. RESULTS: At baseline, median age of the study population (N = 1213) was 45.4 (interquartile range [IQR] 42.1-49.0) years and 70.3% were men. After a median follow-up of 5.1 (IQR 3.9-7.0) years, the incidence was 6.98 (95% confidence interval [CI], 5.19-9.38) per 1000 person-years for total ASCVD events, 4.01 (2.78-6.00) for coronary and/or cerebral events, and 3.17 (2.05-4.92) for PAD ASCVD events. Aging (hazard ratio [HR] 1.06; 95% CI, 1.01-1.12), prior CVD (HR 8.48; 95% CI, 3.14-22.91), high total cholesterol (HR 1.43; 95% CI, 1.11-1.83), high-density lipoprotein cholesterol (HR 0.22; 95% CI, 0.08-0.63), statin use (HR 3.31; 95% CI, 1.31-8.38), and high alcohol intake (HR 3.18; 95% CI, 1.35-7.52) were independently associated with total ASCVD events, whereas undetectable baseline viral load (HR 0.41, 95% CI, 0.18-0.96) was associated with coronary and/or cerebral events. CONCLUSIONS: HIV-HCV coinfected patients experienced a high incidence of ASCVD events. Some traditional cardiovascular risk factors were the main determinants of ASCVD. Controlling cholesterol abnormalities and maintaining undetectable HIV RNA are essential to control cardiovascular risk.

Proliferative memory SAMHD1low CD4+ T cells harbour high levels of HIV-1 with compartmentalized viral populations.

We previously reported the presence of memory CD4+ T cells that express low levels of SAMHD1 (SAMHD1low) in peripheral blood and lymph nodes from both HIV-1 infected and uninfected individuals. These cells are enriched in Th17 and Tfh subsets, two populations known to be preferentially targeted by HIV-1. Here we investigated whether SAMHD1low CD4+ T-cells harbour replication-competent virus and compartimentalized HIV-1 genomes. We sorted memory CD4+CD45RO+SAMHD1low, CD4+CD45RO+SAMHD1+ and naive CD4+CD45RO-SAMHD1+ cells from HIV-1-infected patients on anti-retroviral therapy (c-ART) and performed HIV-1 DNA quantification, ultra-deep-sequencing of partial env (C2/V3) sequences and phenotypic characterization of the cells. We show that SAMHD1low cells include novel Th17 CCR6+ subsets that lack CXCR3 and CCR4 (CCR6+DN). There is a decrease of the % of Th17 in SAMHD1low compartment in infected compared to uninfected individuals (41% vs 55%, p<0.05), whereas the % of CCR6+DN increases (7.95% vs 3.8%, p<0.05). Moreover, in HIV-1 infected patients, memory SAMHD1low cells harbour high levels of HIV-1 DNA compared to memory SAMHD1+ cells (4.5 vs 3.8 log/106cells, respectively, p<0.001), while naïve SAMHD1+ showed significantly lower levels (3.1 log/106cells, p<0.0001). Importantly, we show that SAMHD1low cells contain p24-producing cells. Moreover, phylogenetic analyses revealed well-segregated HIV-1 DNA populations with compartmentalization between SAMHD1low and SAMHD1+ memory cells, and limited viral exchange. As expected, the % of Ki67+ cells was significantly higher in SAMHD1low compared to SAMHD1+ cells. There was positive association between levels of HIV-1 DNA and Ki67+ in memory SAMHD1low cells, but not in memory and naïve SAMHD1+ CD4+ T-cells. Altogether, these data suggest that proliferative memory SAMHD1low cells contribute to viral persistence.

IKZF1 Gene Deletion in Pediatric Patients Diagnosed with Acute Lymphoblastic Leukemia in Mexico.

The IKZF1 gene is formed by 8 exons and encodes IKAROS, a transcription factor that regulates the expression of genes that control cell cycle progression and cell survival. In general, 15-20% of the patients with preB acute lymphoblastic leukemia (preB ALL) harbor IKZF1 deletions, and the frequency of these deletions increases in BCR-ABL1 or Ph-like subgroups. These deletions have been associated with poor treatment response and the risk of relapse. The aim of this descriptive study was to determine the frequency of IKZF1 deletions and the success of an induction therapy response in Mexican pediatric patients diagnosed with preB ALL in 2 hospitals from 2017 to August 2018. Thirty-six bone marrow samples from patients at the Instituto Nacional de Pediatría in Mexico City and the Centro Estatal de Cancerología in Tepic were analyzed. The IKZF1 deletion was identified by MLPA using the SALSA MLPA P335 ALL-IKZF1 probemix. Deletions of at least 1 IKZF1 exon were observed in 7/34 samples (20.6%): 3 with 1 exon deleted; 1 with 2 exons, 1 with 5 exons, 1 with 6 exons, and 1 patient with a complete IKZF1 deletion. This study was descriptive in nature; we calculated the frequency of the IKZF1 gene deletion in a Mexican pediatric population with preB ALL as 20.6%.

Persistent decrease of renal functional reserve in patients after cardiac surgery-associated acute kidney injury despite clinical recovery.

Background: Cardiac surgery is a leading cause of acute kidney injury (AKI). Such AKI patients may develop progressive chronic kidney disease (CKD). Others, who appear to have sustained no permanent loss of function (normal serum creatinine), may still lose renal functional reserve (RFR). Methods: We extended the follow-up in the observational 'Preoperative RFR Predicts Risk of AKI after Cardiac Surgery' study from hospital discharge to 3 months after surgery for 86 (78.2%) patients with normal baseline estimated glomerular filtration rate (eGFR), and re-measured RFR with a high oral protein load. The primary study endpoint was change in RFR. Study registration at clinicaltrials.gov Identifier: NCT03092947, ISRCTN Registry: ISRCTN16109759. Results: At 3 months, three patients developed new CKD. All remaining patients continued to have a normal eGFR (93.3 ± 15.1 mL/min/1.73 m2). However, when stratified by post-operative AKI and cell cycle arrest (CCA) biomarkers, AKI patients displayed a significant decrease in RFR {from 14.4 [interquartile range (IQR) 9.5 - 24.3] to 9.1 (IQR 7.1 - 12.5) mL/min/1.73 m2; P < 0.001} and patients without AKI but with positive post-operative CCA biomarkers also experienced a similar decrease of RFR [from 26.7 (IQR 22.9 - 31.5) to 19.7 (IQR 15.8 - 22.8) mL/min/1.73 m2; P < 0.001]. In contrast, patients with neither clinical AKI nor positive biomarkers had no such decrease of RFR. Finally, of the three patients who developed new CKD, two sustained AKI and one had positive CCA biomarkers but without AKI. Conclusions: Among elective cardiac surgery patients, AKI or elevated post-operative CCA biomarkers were associated with decreased RFR at 3 months despite normalization of serum creatinine. Larger prospective studies to validate the use of RFR to assess renal recovery in combination with biochemical biomarkers are warranted.

Impaired neutrophil extracellular traps and inflammatory responses in the peritoneal fluid of patients with liver cirrhosis.

Liver cirrhosis (LC) is an inflammatory process associated with impaired functions in adaptive and innate immune responses at both systemic and local levels, also referred as Cirrhosis-Associated Immune Dysfunction. In this study, we evaluated the functionality of neutrophils from ascitic fluid (AF) of patients with hepatic cirrhosis by testing their ability to generate neutrophil extracellular traps (NETs) in vitro. To further determine the activation state of neutrophils, expression of the activation markers CD66b, CD69, and CD80 on these cells was analysed by flow cytometry. The inflammatory environment in AF was assessed by measured concentration of pro- and anti-inflammatory cytokines. Samples were collected from 40 patients with LC, 20 of them with uncomplicated ascites (ASC) and 20 with spontaneous bacterial peritonitis (SBP). Peripheral blood (PB) neutrophils from healthy individuals were used as control (HC). Our results revealed a significant decrease in the release of NETs in neutrophils from the SBP group compared with HC. Low expression of CD69 and CD80 on neutrophils from AF of SBP patients was also observed. Comparisons of inflammatory cytokine levels in AF from the different study groups (SBP and ASC) revealed significant differences. In conclusion, we demonstrate that the development of complications, such as SBP, increases initially the inflammatory status, but chronically results in impaired neutrophil function as demonstrated by the decreased capability of NETs formation. There is also an increase in both pro-inflammatory and anti-inflammatory cytokines, thus predisposing for new episodes of SPB and increasing morbidity and mortality in cirrhotic patients.

pirA- and pirB-like gene identification in Micrococcus luteus strains in Mexico.

Acute hepatopancreatic necrosis disease (AHPND) was first reported in China in 2009 and afterwards in Mexico in 2013. AHPND is caused by Vibrio parahaemolyticus and affects Penaeus monodon and Litopenaeus vannamei shrimp cultures. The bacterium contains the pirA- and pirB-like genes in 69- to 70-Kb plasmids, which encode the toxins that produce the disease. The aim of this study was to determine whether pirA- and pirB-like genes existed in bacterial genera distinct from Vibrio before the first cases of AHPND were documented in Mexico. Two bacterial isolates were selected from shrimp farms in Nayarit in 2006 and analysed by nested-PCR to determine the presence of pirA- and pirB-like genes. The two isolates chosen did indeed show the presence of these genes, and those findings were confirmed by sequencing. Both strains matched to the bacterial species Micrococcus luteus. Results revealed two important situations: (a) the pirA- and pirB-like genes were present in a bacterial species that has not been reported previously (Micrococcus luteus); and (b) pirA- and pirB-like bacterial genes were present in Mexico before the first AHPND outbreak was reported in China.

Ferric carboxymaltose with or without erythropoietin in anemic patients with hip fracture: a randomized clinical trial.

BACKGROUND: The increasing incidence of osteoporotic hip fracture (HF) has raised the requirements of red blood cell (RBC) transfusions, whereas this scarce resource may cause morbidity and mortality. STUDY DESIGN AND METHODS: This study was a multicenter, randomized, double-blind, clinical trial that aimed to assess efficacy of ferric carboxymaltose (FCM) with or without erythropoietin (EPO) in reducing RBC transfusion in the perioperative period of HF. Participants (patients > 65 years admitted with HF and hemoglobin [Hb] levels of 90-120 g/L) were randomly assigned to receive a preoperative single dose of 1 g of FCM (short intravenous [IV] infusion over 15 min), plus 40,000 IU of subcutaneous EPO (EPOFE arm); versus 1 g of IV FCM plus subcutaneous placebo (FE arm); and versus IV and subcutaneous placebo (placebo arm). Primary endpoint was the percentage of patients who received RBC transfusion, and secondary endpoints were the number of RBC transfusions per patient, survival, hemoglobinemia, and health-related quality of life (HRQoL; by means of Short Form 36 Version 2 questionnaire). RESULTS: A total of 306 patients (85% women, mean age 83 ± 6.5 years) were included. A total of 52, 51.5, and 54% of patients required RBC transfusion in the EPOFE, FE, and placebo arms, respectively, with no significant differences in the number of RBC transfusions per patient, survival, HRQoL, and adverse events among treatment groups. A significant increase in Hb levels was achieved at discharge (102 g/L vs. 97 g/L) and 60 days after discharge (125 g/L vs. 119 g/L) in the EPOFE arm with respect to placebo arm; in addition, a higher rate of patients recovered from anemia in the EPOFE arm with respect to the placebo arm (52% vs. 39%), 60 days after discharge. CONCLUSION: Preoperative treatment with FCM alone or in combination with EPO improved recovery from postoperative anemia, but did not reduce the needs of RBC transfusion in patients with HF.

Engineering of a microbial coculture of Escherichia coli strains for the biosynthesis of resveratrol.

BACKGROUND: Resveratrol is a plant natural product with many health-protecting effects which makes it an attractive chemical both for academic studies and industrial purposes. However, the low quantities naturally produced by plants as well as the unsustainable procedures of extraction, purification and concentration have prompted many biotechnological approaches to produce this chemical in large quantities from renewable sources. None of these approaches have considered a microbial coculture strategy to produce this compound. The aim of this study was to prove the functionality of a microbial coculture for the biosynthesis of resveratrol. RESULTS: In this work, we have successfully applied a coculture system strategy comprised of two populations of Escherichia coli strains, each with a partial and complementary section of the pathway leading to the biosynthesis of the stilbene resveratrol. The first strain is a pheA knockout mutant previously engineered to excrete p-coumaric acid into the medium through the overexpression of genes encoding a tyrosine ammonia lyase from Rhodothorula glutinis, a feedback resistant 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase and a transketolase. The second strain in the coculture was engineered to express the second part of the resveratrol biosynthetic pathway through the introduction of synthetic genes encoding the 4-coumaroyl-CoA ligase from Streptomyces coelicolor A2 and the stilbene synthase either from the peanut Arachis hypogaea or the grapevine Vitis vinifera, the latter synthesized employing a gene harmonization strategy and showing better resveratrol production performance. Batch cultures were performed in mineral medium with glycerol as the sole carbon source, where a final titer of 22.6 mg/L of resveratrol was produced in 30 h. CONCLUSIONS: To our knowledge, this is the first time that a coculture of bacterial strains is used for the biosynthesis of resveratrol from glycerol, having the potential for a greater improvement in the product yield and avoiding the use of precursors such as p-coumaric acid, yeast extract or an expensive inhibitor such as cerulenin.

Optimizing a kidney stress test to evaluate renal functional reserve.

BACKGROUND: Renal function reserve (RFR) describes the capacity of the kidney to increase glomerular filtration rate (GFR) in response to physiological or pathological stimuli. The scope of our study was to evaluate the optimal level of stimulation using different doses of protein load (PL) for a standard renal stress test (RST). METHODS: 18 young healthy individuals were given sessions of PL with 1 and 2 g/kg body weight. Endogenous creatinine clearance was calculated. Baseline GFR (bGFR) and stress GFR (sGFR) (post-PL) were obtained; RFR is the difference between stress and baseline GFR. A p-value < 0.05 was considered statistically significant. RESULTS: Mean bGFR was 107.97 ± 12.33 mL/min/1.73m2. sGFR with 1 and 2 g PL were significantly higher than bGFR in all subjects. The sGFR after 2 g PL (141.75 ± 19.90 mL/min/1.73m2) was not statistically different from the sGFR after 1 g PL (142.37 ± 22.35 mL/min/1.73m2). sGFR and therefore RFR were independent from the value of bGFR. CONCLUSIONS: We found no difference between 1 and 2 g/kg body weight PL to elicit sGFR. RST may be useful to predict susceptibility and risk of developing acute kidney injury and/or progression to chronic kidney disease. RST uncovers the possible loss of renal functional mass when this condition is not manifested clinically. Further studies are needed to set this hypothesis.

Fabry's disease: an example of cardiorenal syndrome type 5.

Cardiorenal syndrome type 5 (CRS-5) includes conditions where there is a simultaneous involvement of the heart and kidney from a systemic disorder. This is a bilateral organ cross talk. Fabry's disease (FD) is a devastating progressive inborn error of metabolism with lysosomal glycosphingolipid deposition in variety of cell types, capillary endothelial cells, renal, cardiac and nerve cells. Basic effect is absent or deficient activity of lysosomal exoglycohydrolase a-galactosidase A. Renal involvement consists of proteinuria, isosthenuria, altered tubular function, presenting in second or third decade leading to azotemia and end-stage renal disease in third to fifth decade mainly due to irreversible changes to glomerular, tubular and vascular structures, especially highlighted by podocytes foot process effacement. Cardiac involvement consists of left ventricular hypertrophy, right ventricular hypertrophy, arrhythmias (sinus node and conduction system impairment), diastolic dysfunction, myocardial ischemia, infarction, transmural replacement fibrosis, congestive heart failure and cardiac death. Management of FD is based on enzymatic replacement therapy and control of renal (with anti-proteinuric agents such as angiotensin-converting enzyme inhibitors-and/or angiotensin II receptor blockers), brain (coated aspirin, clopidogrel and statin to prevent strokes) and heart complications (calcium channel blockers for ischemic cardiomyopathy, warfarin and amiodarone or cardioverter device for arrhythmias).