Complete agenesis of dorsal pancreas: A rare cause of insulin-dependent diabetes mellitus

ABSTRACT

We report a 16-year-old boy who presented with abdominal pain and severe hyperglycemia. His random blood glucose on admission was above 300 mg/dL, without ketosis. Urine examination revealed mild ketonuria. Renal function tests were normal. Antibodies to glutamate acid decarboxylase (anti-GAD) and islet tyrosine phosphatase 2 (anti-IA2) were negative. Findings on enhanced abdominal computed tomography scan were compatible with complete dorsal pancreatic agenesis. The body and tail of the pancreas were not visualized. Additionally, ectopic and malrotated left kidney was detected. Magnetic resonance cholangiopancreatography confirmed the absence of the dorsal pancreatic duct. The patient was treated with multiple subcutaneous insulin injections and attained good glycemic control. He is currently doing well on follow-up. The present case is a rare combination of complete agenesis of the dorsal pancreas with an ectopic, malrotated kidney. Clinical awareness of this rare association will help improve patient management.

Rapid expansion of Neisseria gonorrhoeae ST7827 clone in Australia, with variable ceftriaxone phenotype unexplained by genotype

BACKGROUND

Neisseria gonorrhoeae is identified as a priority pathogen due to its capacity to rapidly develop antimicrobial resistance (AMR). Following the easing of SARS-CoV-2 pandemic travel restrictions across international borders in the state of New South Wales (NSW), Australia, a surge of gonococcal isolates with raised ceftriaxone MIC values were detected.

METHODS

All N. gonorrhoeae isolates (n = 150) with increased ceftriaxone MIC values in NSW between 1 January 2021 and July 2022 from males and females from all sites were sequenced.

RESULTS

A new emergence and rapid expansion of an N. gonorrhoeae ST7827 clone was documented within NSW, Australia and provides further evidence of the ability of N. gonorrhoeae to undergo sufficient genomic changes and re-emerge as a geographically restricted subclone. Mapping AMR determinants to MIC results did not reveal any genomic pattern that correlated with MIC values.

CONCLUSIONS

The rapid dissemination and establishment of this clone at the population level is a new and concerning demonstration of the agility of this pathogen, and underscores concerns about similar incursions and establishment of MDR clones. Moreover, it is notable that in this context the AMR genotype-phenotype correlates remain unclear, which requires further investigation to enable better understanding of genomic aspects of AMR in N. gonorrhoeae.

5S rRNA pseudogene transcripts are associated with interferon production and inflammatory responses in alcohol-associated hepatitis

BACKGROUND AND AIMS

Interferon (IFN) signaling is critical to the pathogenesis of alcohol-associated hepatitis (AH), yet the mechanisms for activation of this system are elusive. We hypothesize that host-derived 5S rRNA pseudogene (RNA5SP) transcripts regulate IFN production and modify immunity in AH.

APPROACH AND RESULTS

Mining of transcriptomic datasets revealed that in patients with severe alcohol-associated hepatitis (sAH), hepatic expression of genes regulated by IFNs was perturbed and gene sets involved in IFN production were enriched. RNA5SP transcripts were also increased and correlated with expression of type I IFNs. Interestingly, inflammatory mediators upregulated in sAH, but not in other liver diseases, were positively correlated with certain RNA5SP transcripts. Real-time quantitative PCR demonstrated that RNA5SP transcripts were upregulated in peripheral blood mononuclear cells (PBMCs) from patients with sAH. In sAH livers, increased 5S rRNA and reduced nuclear MAF1 (MAF1 homolog, negative regulator of RNA polymerase III) protein suggested a higher activity of RNA polymerase III (Pol III); inhibition of Pol III reduced RNA5SP expression in monocytic THP-1 cells. Expression of several RNA5SP transcript-interacting proteins was downregulated in sAH, potentially unmasking transcripts to immunosensors. Indeed, siRNA knockdown of interacting proteins potentiated the immunostimulatory activity of RNA5SP transcripts. Molecular interaction and cell viability assays demonstrated that RNA5SP transcripts adopted Z-conformation and contributed to ZBP1-mediated caspase-independent cell death.

CONCLUSIONS

Increased expression and binding availability of RNA5SP transcripts was associated with hepatic IFN production and inflammation in sAH. These data identify RNA5SP transcripts as a potential target to mitigate inflammation and hepatocellular injury in AH.

Beta-blockers and mechanical dyssynchrony in heart failure assessed by radionuclide ventriculography

BACKGROUND

Radionuclide ventriculography (RNVG) can be used to quantify mechanical dyssynchrony and may be a valuable adjunct in the assessment of heart failure with reduced ejection fraction (HFrEF). The study aims to investigate the effect of beta-blockers on mechanical dyssynchrony using novel RNVG phase parameters.

METHODS

A retrospective study was carried out in a group of 98 patients with HFrEF. LVEF and dyssynchrony were assessed pre and post beta-blockade. Dyssynchrony was assessed using synchrony, entropy, phase standard deviation, approximate entropy, and sample entropy from planar RNVG phase images. Subgroups split by ischemic etiology were also investigated.

RESULTS

An improvement in dyssynchrony and LVEF was measured six months post beta-blockade for both ischemic and non-ischemic groups.

CONCLUSIONS

A significant improvement in dyssynchrony and LVEF was measured post beta-blockade using novel measures of dyssynchrony.

Recent Advances in Understanding of Pathogenesis of Alcohol-Associated Liver Disease

Alcohol-associated liver disease (ALD) is one of the major diseases arising from chronic alcohol consumption and is one of the most common causes of liver-related morbidity and mortality. ALD includes asymptomatic liver steatosis, fibrosis, cirrhosis, and alcohol-associated hepatitis and its complications. The progression of ALD involves complex cell-cell and organ-organ interactions. We focus on the impact of alcohol on dysregulation of homeostatic mechanisms and regulation of injury and repair in the liver. In particular, we discuss recent advances in understanding the disruption of balance between programmed cell death and prosurvival pathways, such as autophagy and membrane trafficking, in the pathogenesis of ALD. We also summarize current understanding of innate immune responses, liver sinusoidal endothelial cell dysfunction and hepatic stellate cell activation, and gut-liver and adipose-liver cross talk in response to ethanol. In addition,we describe the current potential therapeutic targets and clinical trials aimed at alleviating hepatocyte injury, reducing inflammatory responses, and targeting gut microbiota, for the treatment of ALD.

Periplasmic stress contributes to a tradeoff between protein secretion and cell growth in E. Coli Nissile

Maximizing protein secretion is an important target in the design of engineered living systems. In this paper, we characterize a tradeoff between cell growth and per cell protein secretion in the curli biofilm secretion system of E Coli Nissile 1917. Initial characterization using 24-hour continuous growth and protein production monitoring confirms decreased growth rates at high induction leading to a local maximum in total protein production at intermediate induction. Propidium iodide staining at the endpoint indicates that cellular death is a dominant cause of growth reduction. Assaying variants with combinatorial constructs of inner and outer membrane secretion tags, we find that diminished growth at high production is specific to secretory variants associated with accumulation of protein containing the outer membrane transport tag in the periplasmic space. RNA sequencing experiments indicate upregulation of known periplasmic stress response genes in the highly secreting variant, further implicating periplasmic stress in the growth-secretion tradeoff. Overall, these results motivate additional strategies for optimizing total protein production and longevity of secretory engineered living systems.

35kDa hyaluronan ameliorates ethanol driven loss of anti-microbial defense and intestinal barrier integrity in a TLR4-dependent manner

Acute and chronic alcohol exposure compromise intestinal epithelial integrity, due to reduced expression of anti-microbial peptides (AMP) and loss of tight junction integrity. Ameliorating gut damage is beneficial in preventing associated distant organ pathologies. Orally administered purified hyaluronan (HA) polymers with an average size of 35 kDa have multiple protective effects in the gut and are well-tolerated in humans. Therefore, we tested the hypothesis that HA35 ameliorates ethanol-induced gut damage. Specifically, mechanisms that restore epithelial barrier integrity and normalize expression of the Reg3 class of C-type lectin AMPs (i.e. Reg3β and Reg3γ) were investigated. Chronic ethanol feeding to mice reduced expression of C-type lectin AMPs in the proximal small intestine (jejunum), reduced expression of tight junction proteins and increased bacterial translocation to the mesenteric lymph node. Oral consumption of HA35 during the last 6 days of ethanol exposure ameliorated the effects of chronic ethanol. Similarly, in vitro challenge of isolated intestinal organoids from murine jejunum with ethanol reduced the expression of C-type lectin AMPs and impaired barrier integrity; these ethanol-induced responses were prevented by pre-treatment with HA35. Importantly, HA receptor null jejunum-derived organoids demonstrated that the HA receptor Tlr4, but not Cd44 nor Tlr2, was required for the protective effect of HA35. Consistent with the data from organoids, HA35 did not protect Tlr4-deficient mice from chronic ethanol-induced intestinal injury. Together, these data suggest therapeutic administration of HA35 is beneficial in restoring gut epithelial integrity and defense during the early stages of ethanol-driven intestinal damage.

Radionuclide ventriculography phase analysis for risk stratification of patients undergoing cardiotoxic cancer therapy

BACKGROUND

Accurate diagnostic tools to identify patients at risk of cancer therapy-related cardiac dysfunction (CTRCD) are critical. For patients undergoing cardiotoxic cancer therapy, ejection fraction assessment using radionuclide ventriculography (RNVG) is commonly used for serial assessment of left ventricular (LV) function.

METHODS

In this retrospective study, approximate entropy (ApEn), synchrony, entropy, and standard deviation from the phase histogram (phase SD) were investigated as potential early markers of LV dysfunction to predict CTRCD. These phase parameters were calculated from the baseline RNVG phase image for 177 breast cancer patients before commencing cardiotoxic therapy.

RESULTS

Of the 177 patients, 11 had a decline in left ventricular ejection fraction (LVEF) of over 10% to an LVEF below 50% after treatment had commenced. This patient group had a significantly higher ApEn at baseline to those who maintained a normal LVEF throughout treatment. Of the parameters investigated, ApEn was superior for predicting the risk of CTRCD. Combining ApEn with the baseline LVEF further improved the discrimination between the groups.

CONCLUSIONS

The results suggest that RNVG phase analysis using approximate entropy may aid in the detection of sub-clinical LV contraction abnormalities, not detectable by baseline LVEF measurement, predicting a subsequent decline in LVEF.

Impact of plasma glucose and duration of type 2 diabetes mellitus on SYNTAX Score II in patients suffering from non ST-elevation myocardial infarction

Aim    The objective was to assess the correlation of fasting plasma glucose (FPG), HbA1c, and the duration of type 2 diabetes mellitus (T2DM) with SYNTAX score (SS) II in patients with non-ST elevation myocardial infarction (NSTEMI).Material and methods    FPG and HbA1C were measured in 398 patients presenting with NSTEMI at admission. SS II was calculated using an online calculator. Patients were stratified according to SS II (≤21.5, 21.5-30.6, and ≥30.6), defined as SS II low, mid, and high, respectively.Results    37.7 % of subjects were diabetic. Correlations of FPG (R=0.402, R2=0.162, p<0.001) and HbA1c (R=0.359, R2=0.129, p<0.001) with SS II were weak in the overall population. Duration of T2DM showed very strong correlation with SS II (R=0.827, R2=0.347). For the prediction of high SS II in the study population, FPG≥98.5 mg / dl demonstrated a sensitivity of 58 % and a specificity of 60 %, and HbA1c ≥6.05 demonstrated a sensitivity of 63 % and a specificity of 69 %. Duration of T2DM (adjusted odds ratio (OR): 1.182; 95 % confidence interval (CI): 1.185-2.773) and FPG (OR: 0.987; 95 % CI: 0.976-0.9959) were significantly associated with high SS II after controlling for other risk factors. Duration of T2DM (Beta=0.439) contributed strongly to variance of SS II, whereas HbA1c (Beta=0.063) contributed weakly.Conclusion    Duration of T2DM is a very important risk factor for severity of coronary artery disease.

Relative contribution of different members of OsDREB gene family to osmotic stress tolerance in indica and japonica ecotypes of rice

Drought/osmotic stress is the single largest production constraint in rain-fed rice cultivation. Different members of the DREB gene family are known to contribute to osmotic stress tolerance. In this study, an attempt was made to understand their relative contribution towards osmotic stress tolerance in indica and japonica ecotypes of rice. Two genotypes (one tolerant and one susceptible) from each ecotype were grown hydroponically, and 21-day-old seedlings were subjected to polyethylene glycol-induced osmotic stress (15% PEG-6000, equivalent to -3.0 bars osmotic potential). The tolerant genotypes CR143 and Moroberekan were found to have superior root traits (total root length, surface area and volume), better plant water status and increased total dry biomass as compared to their susceptible counterparts after 10 days of osmotic stress. Different members of the DREB gene family were differentially induced in response to osmotic shock (1 h after stress) and osmotic stress (24 h after stress), which also differed between the two rice ecotypes. From the gene expression profiles of 10 DREB genes (both DREB1 and DREB2 families), in indica two DREB genes, DREB1B and DREB1G, were significantly correlated with stress tolerance indices, whereas in japonica significant correlations with five DREB genes (DREB1A, DREB1B, DREB1D, DREB1E and DREB2B) were observed. We found that only one member, i.e. DREB1B, showed a significant correlation with drought tolerance indices in both indica and japonica ecotypes. This study provides an overview of the relative contribution of different members of the DREB gene family and their association with drought/osmotic stress tolerance in rice.

Efficacy and safety of bisoprolol compared to other selective beta-1 blockers in the treatment of hypertension: a systematic review and meta-analysis of randomized parallel clinical trials

Background

Bisoprolol, a highly cardioselective beta-1 blocker (s-BB) has theoretical advantage over other cardio selective betablockers by way of better potency and tolerability in treating hypertension (HT). Individual published trials comparing s-BB are typically small. Meta-analysis of such trials clarifies the issue and position of bisoprolol in HT therapy.

Purpose

This meta-analysis compares bisoprolol with other s-BBs (Atenolol, Betaxolol, Esmolol, Acebutolol, Metoprolol, Nebivolol) for their efficacy and safety in patients with HT.

Methods

Literature databases PubMed, Embase, Cochrane Library, Clinicaltrials.gov, Surveillance, Epidemiology and End Results Program and 12 PV databases were searched systematically to identify randomized, parallel clinical trials published from inception to October 2019. Studies which compared bisoprolol with other s-BBs in HT patients were evaluated in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Random effects meta-analyses were conducted to assess mean difference (MD) and 95% confidence interval (95% CI) for blood pressure (BP), heart rate (HR) and lipid profile.

Results

13 studies compared bisoprolol with other s-BBs (metoprolol, atenolol) were included in this meta-analysis. Bisoprolol reported significant reduction in aortic systolic BP [MD: −8.00; 95% CI: −11.57, −4.43; P<0.01] and diastolic BP [MD: −2.90; 95% CI: −4.98, −0.82; P<0.01] during 8 weeks (w) treatment compared to other s-BBs. Bisoprolol treatment for 12w showed significant change in ambulatory heart rate (AHR) [MD: −5.22; 95% CI: −8.37, −2.07; P<0.01], daytime AHR [MD: −5.75; 95% CI: −9.16, 2.34; P<0.01] and nighttime AHR [MD: −3.22; 95% CI: −6.18, −0.26; P=0.03] in comparison to other s-BBs. Significant increase in low frequency HR variability [MD: 100.79; 95% CI: 16.66, 184.91; P=0.02] was reported with bisoprolol treated for 8w compared to other s-BBs. Baroreflex sensitivity significantly favored bisoprolol treated for 8w [MD: 1.01; 95% CI: 0.03, 1.98; P=0.04] in comparison to other s-BBs. HDL-C significantly increased with bisoprolol treated for 52w [MD: 6.80; 95% CI: 3.01, 10.60; P<0.01], 104w [MD: 12.00; 95% CI: 5.04, 18.96; P<0.01] and 156w [MD: 8.00; 95% CI: 0.58, 15.42; P=0.03]. There were no significant changes in total cholesterol [MD: −3.06; P=0.38], LDL-C [MD: −3.60; P=0.18] and triglyceride [MD: −21.00; P=0.26] on treatment with bisoprolol. Serious adverse events did not differ significantly on treatment with bisoprolol compared to other s-BBs.

Conclusion

The results of this meta-analysis reveal that bisoprolol showed a significant reduction of BP, HR, baroreflex sensitivity and improved HDL cholesterol levels compared to other s-BBs. Our results highlight the heterogeneity amongst the s-BBs and highlights the benefit of choosing bisoprolol in comparison to other s-BB in the management of HT.

Funding Acknowledgement

Type of funding sources: None.

Effectiveness of bisoprolol versus selective beta-1 blockers in the management of hypertension: a systematic review and meta-analysis of randomized cross-over trials

Background

Cross-over trials carry a higher weightage in choosing a therapeutic agent in clinical practice. A meta-analysis of cross-over trials involving the use of bisoprolol in hypertension (HT) would bring about clarity in positioning this drug.

Purpose

The present study aimed to clarify the underlying benefits of bisoprolol in the reduction of blood pressure (BP) in HT patients when compared to selective beta-1 blockers (s-BBs - Atenolol, Betaxolol hydrochloride, Esmolol, Acebutolol hydrochloride, Metoprolol succinate, Nebivolol) by performing a meta-analysis of “cross-over” trials published in literature.

Methods

Systematic search was undertaken in PubMed, Embase, Cochrane Library, Clinicaltrials.gov registry, Surveillance, Epidemiology and End Results Program and 12 pharmacovigilance databases. Randomized, cross-over studies published up to October 2019 which compared bisoprolol with other s-BBs in HT patients were evaluated in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A meta-analysis was performed using random effects model in terms of mean difference (MD) and 95% confidence intervals (95% CI) for BP, heart rate (HR) and lipid profile.

Results

Nine randomized cross-over studies which compared bisoprolol with other s-BBs (atenolol and nebivolol) were included in this meta-analysis. Bisoprolol reported significant reduction of sitting BP [MD: −3.35, 95% CI: −6.75, 0.05; P=0.05] and reduction of diastolic BP [MD: −2.00; 95% CI: −8.04, 4.04; P=0.52, non-significant] among patients with HT when compared to other s-BBs. Heart rate (HR) decreased significantly among HT patients in bisoprolol group treated for 2 w [MD: −6.00; 95% CI: −11.30, −0.70; P=0.03] when compared to those treated with other s-BBs. Analysis of lipid profile showed non-significant reduction of serum cholesterol [MD: −7.74; 95% CI: −17.18, 1.70; P=0.11] and triglyceride [MD: −26.57; 95% CI: −64.34, 11.20; P=0.17] levels in the bisoprolol group compared to other s-BBs. Bisoprolol treatment for 8 w resulted in a slight but statistically significant change in potassium levels [MD: −0.10; 95% CI: −0.16, −0.04; P<0.01] among HT patients.

Conclusion

The results of this meta-analysis reported significant efficacy of bisoprolol on BP and HR in comparison to other s-BBs in a meta-analysis of cross-over trials. Our findings show that use of bisoprolol as a therapeutic option is efficacious and safe compared to other s-BBs in this patient population.

Funding Acknowledgement

Type of funding sources: None.

Effects of Vector Maturation Time on the Dynamics of Cassava Mosaic Disease

Many plant diseases are caused by plant viruses that are often transmitted to plants by vectors. For instance, the cassava mosaic disease, which is spread by whiteflies, has a significant negative effect on plant growth and development. Since only mature whiteflies can contribute to the spread of the cassava mosaic virus, and the maturation time is non-negligible compared to whitefly lifetime, it is important to consider the effects this maturation time can have on the dynamics. In this paper, we propose a mathematical model for dynamics of cassava mosaic disease that includes immature and mature vectors and explicitly includes a time delay representing vector maturation time. A special feature of our plant epidemic model is that vector recruitment is negatively related to the delayed ratio between vector density and plant density. We identify conditions of biological feasibility and stability of different steady states in terms of system parameters and the time delay. Numerical stability analyses and simulations are performed to explore the role of various parameters, and to illustrate the behaviour of the model in different dynamical regimes. We show that the maturation delay may stabilise epidemiological dynamics that would otherwise be cyclic.

Salmonella Typhimurium encoded cold shock protein E is essential for motility and biofilm formation

The ability of bacteria to form biofilms increases their survival under adverse environmental conditions. Biofilms have enormous medical and environmental impact; consequently, the factors that influence biofilm formation are an important area of study. In this investigation, the roles of two cold shock proteins (CSP) during biofilm formation were investigated in Salmonella Typhimurium, which is a major foodborne pathogen. Among all CSP transcripts studied, the expression of cspE (STM14_0732) was higher during biofilm growth. The cspE deletion strain (ΔcspE) did not form biofilms on a cholesterol coated glass surface; however, complementation with WT cspE, but not the F30V mutant, was able to rescue this phenotype. Transcript levels of other CSPs demonstrated up-regulation of cspA (STM14_4399) in ΔcspE. The cspA deletion strain (ΔcspA) did not affect biofilm formation; however, ΔcspEΔcspA exhibited higher biofilm formation compared to ΔcspE. Most likely, the higher cspA amounts in ΔcspE reduced biofilm formation, which was corroborated using cspA over-expression studies. Further functional studies revealed that ΔcspE and ΔcspEΔcspA exhibited slow swimming but no swarming motility. Although cspA over-expression did not affect motility, cspE complementation restored the swarming motility of ΔcspE. The transcript levels of the major genes involved in motility in ΔcspE demonstrated lower expression of the class III (fliC, motA, cheY), but not class I (flhD) or class II (fliA, fliL), flagellar regulon genes. Overall, this study has identified the interplay of two CSPs in regulating two biological processes: CspE is essential for motility in a CspA-independent manner whereas biofilm formation is CspA-dependent.

The role of infrared dermal thermometry in the management of neuropathic diabetic foot ulcers

AIM

This prospective observational study evaluated the role of infrared (IR) dermal thermometry in the management of diabetic foot ulcers.

METHODS

Thirty participants with unilateral neuropathic diabetic foot ulcers of University of Texas grade 1 or 2 (stage A) were followed up monthly for 1 year. At each visit, skin temperatures were measured with an IR dermal thermometer at corresponding sites on both feet, using the contralateral feet without ulcers as controls.

RESULTS

Average temperature and ulcer temperature in affected feet were significantly higher than in unaffected feet, with a mean difference of 1.2 °C [95% confidence interval (CI) 0.7 to 1.7] and 3.1 °C (95% CI 2.3 to 3.9), respectively. Although the gradient between average temperature of affected foot and that of unaffected foot normalized (mean difference 0.2 °C, 95% CI -0.2 to 0.7) at healing, the temperature gradient between the ulcer and a corresponding site on the unaffected foot decreased but did not normalize (mean difference 2.1 °C, 95% CI 1.2 to 3.1) even at healing, as documented by skin closure, and persisted for up to 1 month after skin closure. A gradient of ≥1 °C between average temperature of affected foot and that of unaffected foot at initial presentation or at any time during ulcer healing was found to predict impaired healing and should alert clinicians to ulcers requiring more attention. An incremental trend in temperature gradient (median difference 2.2 °C; range 0.1-6.3 °C) at a site on the foot was predictive of a recurrent ulcer involving the same site.

CONCLUSIONS

IR dermal thermometry may have a role in predicting diabetic foot ulcer healing, in determining the completeness of healing and in guiding the duration of offloading. Serial monitoring of the temperature gradient may predict the development of recurrent diabetic foot ulcers.

Multicellular String-Like Structure Formation by Salmonella Typhimurium Depends on Cellulose Production: Roles of Diguanylate Cyclases, YedQ and YfiN

Bacteria face diverse stresses in the environment and, sometimes, respond by forming multi-cellular structures, e.g., biofilms. Here, we report a novel macroscopic and multi-cellular structure formed by Salmonella Typhimurium, which resembles small strings. These string-like structures, ∼1 cm long, are induced under some stress conditions: iron deprivation by 2,2-Bipyridyl or low amounts of antibiotics or ethanol in minimal media. However, cells in strings revert back to planktonic growth upon return to nutrient rich media. Compared to planktonic cells, strings are more resistant to antibiotics and oxidative stress. Also, strains lacking csgD or rpoS, which are defective in the classical rdar biofilm formation, form strings. Furthermore, some biofilm inducing conditions do not result in strings and vice-versa, demonstrating that strings are not related to classical CsgD-dependent biofilms. Cells in a string are held together by cellulose and a strain lacking bcsA, which is defective in cellulose production, does not form strings. In addition, reductive stress conditions such as dithiothreitol (DTT) or mutations in the Disulfide bonding system (DSB) also give rise to strings. The amounts of c-di-GMP are increased upon string formation and studies with single and double deletion strains of the diguanylate cyclases, yedQ (STM1987) primarily and yfiN (STM2672) partly, revealed their importance for string formation. This is the first study showcasing the ability of Salmonella to produce high amounts of cellulose in liquid culture, instead of an interface, in a CsgD-independent manner. The relevance and possible applications of strings in the production of bacterial cellulose and bioremediation are discussed.

Discrepancies between the decisions of an endocarditis team and the modified Duke's Criteria for the diagnosis of infective endocarditis

Background/Introduction

The 2015 ESC endocarditis guidelines recommend that a multi-disciplinary endocarditis team should be involved in caring for patients with endocarditis. This approach recognises the heterogeneity of infective endocarditis, and the difficulty in distinguishing endocarditis from other infective and non-infective diseases.

Purpose

This study looks at suspected cases of infective endocarditis discussed at the endocarditis MDT, discrepancies between MDT outcome and the modified Duke's criteria in diagnosing endocarditis, and number of referrals to MDT over time.

Methods

Patients were identified by review of MDT outcome forms. Demographic data, predisposing conditions, imaging findings, microbiology results and final diagnosis were identified by reviewing MDT forms and electronic charts.

Results

234 patients were identified from MDT outcome forms. 118 (50.4%) patients were over 65, 165 (70.5%) were male, and 65 (27.8%) had previous valve surgery. Crosstabulation of MDT decision against outcome by modified Duke's criteria are seen in Table 1. The endocarditis team identified 7 patients with definite or possible endocarditis who were excluded by applying the modified Duke's criteria. 1 of these patients required aortic valve replacement. 2 patients with disseminated Staphylococcal infections without endocarditis were classed as definite endocarditis by the modified Duke's criteria. Referral data and outcomes are included in Figure 1.

Conclusions

The endocarditis team can be used to improve the sensitivity and specificity of the modified Duke's criteria. As the endocarditis team became established the volume of referrals has increased, along with the number of patients who have alternate diagnoses. Practitioners should bear this in mind when establishing endocarditis teams.

Figure 1. Referrals over time by outcome

Funding Acknowledgement

Type of funding source: None

Changes in access to educational and healthcare services for individuals with intellectual and developmental disabilities during COVID-19 restrictions

BACKGROUND

COVID-19 restrictions have significantly limited access to in-person educational and healthcare services for all, including individuals with intellectual and developmental disabilities (IDDs). The objectives of this online survey that included both national and international families were to capture changes in access to healthcare and educational services for individuals with IDDs that occurred shortly after restrictions were initiated and to survey families on resources that could improve services for these individuals.

METHODS

This was an online survey for caregivers of individuals with (1) a genetic diagnosis and (2) a neurodevelopmental diagnosis, including developmental delay, intellectual disability, autism spectrum disorder or epilepsy. The survey assessed (1) demographics, (2) changes in access to educational and healthcare services and (3) available and preferred resources to help families navigate the changes in service allocation.

RESULTS

Of the 818 responses (669 within the USA and 149 outside of the USA), most families reported a loss of at least some educational or healthcare services. Seventy-four per cent of parents reported that their child lost access to at least one therapy or education service, and 36% of respondents lost access to a healthcare provider. Only 56% reported that their child received at least some continued services through tele-education. Those that needed to access healthcare providers did so primarily through telemedicine. Telehealth (both tele-education and telemedicine) was reported to be helpful when available, and caregivers most often endorsed a need for an augmentation of these remote delivery services, such as 1:1 videoconference sessions, as well as increased access to 1:1 aides in the home.

CONCLUSIONS

COVID-19 restrictions have greatly affected access to services for individuals with syndromic IDDs. Telehealth may provide opportunities for delivery of care and education in a sustainable way, not only as restrictions endure but also after they have been lifted.

Mobile Teaching Kitchen Project – eradicating and preventing malnutrition through nutrition education

Background

Global malnutrition, affecting over 2.6 billion people globally, represents a triple burden to health in the form of micronutrient deficiencies, under-and over-nutrition. Malnutrition reaches all parts of society, with those undernourished and deficient in vitamins and minerals often thought to be the poorer in society, whilst overnourished those wealthier. NNEdPro, an international think-tank working to develop nutrition capacity, performed a landscaping activity in Kolkata, India and noted significant undernutrition within the slum dwelling population and overnutrition among the inner-city workers.

Results

NNEdPro' s Mobile Teaching Kitchen (MTK) project was developed as a nutritional education tool to improve awareness of diet diversity and disease prevention amongst marginalised communities by using locally sourced foods and cooking skills. Local volunteers trained in healthy cooking transfers core principles through cooking demonstrations of sustainable, nutritional, and affordable meals. They follow a 'See One, Do One, Teach One' (S1D1T1) model to transfer knowledge to their peers. This model aims to create a sustainable solution that will enable the rural-urban slum dwellers across regions of the world to challenge food insecurity and malnutrition.

Conclusions

The potential of the Teaching Kitchen can extend beyond creating powerful behavior change for improved health and nutrition within local communities of both developing and developed countries. In addition to improving the wellbeing of the community, the project can also potentially create livelihood opportunities through empowering women with catering skills and having a positive impact on the health and nutritional status of the wider community. After successful impacts in India, the Mobile Teaching Kitchen model has been proposed to other 8 existing regional networks of NNEdPro such as Australia & New Zealand, Brazil, Italy, Mexico, Morocco, Switzerland, USA, and UK.

Cardiological society of India document on safety measure during echo evaluation of cardiovascular disease in the time of COVID-19

An echocardiographic investigation is one of the key modalities of diagnosis in cardiology. There has been a rising presence of cardiological comorbidities in patients positive for COVID-19. Hence, it is becoming extremely essential to look into the correct safety precautions, healthcare professionals must take while conducting an echo investigation. The decision matrix formulated for conducting an echocardiographic evaluation is based on presence or absence of cardiological comorbidity vis-à-vis positive, suspected or negative for COVID-19. The safety measures have been constructed keeping in mind the current safety precautions by WHO, CDC and MoHFW, India.

Cardiological Society of India: Document on acute MI care during COVID-19

The unprecedented and rapidly spreading Coronavirus Disease-19 (COVID-19) pandemic has challenged public health care systems globally. Based on worldwide experience, India has initiated a nationwide lockdown to prevent the exponential surge of cases. During COVID-19, management of cardiovascular emergencies like acute Myocardial Infarction (MI) may be compromised. Cardiological Society of India (CSI) has ventured in this moment of crisis to evolve a consensus document for care of acute MI. However, this care should be individualized, based on local expertise and governmental advisories.

Insights into coumarin-mediated inhibition of biofilm formation in Salmonella Typhimurium

Coumarins have been shown to possess antimicrobial, anti-quorum sensing and anti-biofilm properties against a wide range of pathogenic bacteria. This study aimed to shed light on the effects of non-substituted coumarin on biofilm formation by the foodborne pathogen Salmonella Typhimurium. Additionally, its efficacy was tested in combination with another potent anti-biofilm agent, resveratrol. Coumarin inhibited biofilm formation for prolonged periods in millimolar concentrations with marginal effects on planktonic growth. It attenuated curli and cellulose production, likely by downregulating the transcript levels of major biofilm formation genes csgD, csgA and adrA. Coumarin further restricted motility in a dose-dependent manner. In addition, coumarin with resveratrol exhibited improved anti-biofilm properties compared with the individual compounds alone. Thus, coumarin alone or with resveratrol can be employed for inhibiting biofilms in food storage and processing units.

The association of dietary patterns and carotid intima-media thickness: A synthesis of current evidence

AIMS

Dietary pattern (DP) analysis has emerged as a holistic method to understand the effects of food intake on health outcomes. Though dietary intake has been associated with cardiovascular disease, the association of DPs and carotid intima-media thickness (CIMT), a robust early marker of cardiovascular disease progression has not been comprehensively investigated. This study systematically explores the association of a posteriori and a priori DPs and CIMT.

DATA SYNTHESIS

Through a systematic search of MEDLINE, CINAHL, and Web of Science, twenty studies that derived DPs using a posteriori or a priori methods with CIMT as an outcome were included. Four cross-sectional studies and 1 cohort paper reported a statistically significant association between increased consumption of 'unhealthy' foods (i.e processed meat, soda drinks and refined grain) and increased CIMT. While four cross-sectional studies reported a statistically significant association of DPs characterized by increased consumption of 'healthy' foods (i.e fruit and vegetables, fish) and decreased CIMT. DPs derived from each study varied depending on derivation method, study design and use of dietary data collection method.

CONCLUSION

Findings from this review are generally supportive of a trend between DPs with higher consumption of 'healthy' foods and lower consumption of 'unhealthy' foods and decreased CIMT; however, the association was largely not statistically significant. Evidence was overwhelmingly heterogeneous due to differences seen in DPs based on location and culture, sample characteristics and adjustment for confounders. Long-term prospective observational and interventional studies with standardized sample selection and dietary data collection are needed to significantly establish the role of DPs on CIMT.

P3779NT-proBNP adds incremental predictive information on incident atrial fibrillation in patients with asymptomatic aortic stenosis

Background

Incident atrial fibrillation (AF) marks an adverse shift in the prognosis of patients with aortic stenosis (AS). Identifying risk factors for AF is therefore of paramount importance for timely intervention in patients with AS. In patients without AS, brain natriuretic peptides (BNP) is a well-established biomarker for left ventricular pressure overload on the pathway to heart failure and atrial fibrillation. However, a potential role of NT-proBNP to predict risk of new-onset AF in asymptomatic patients with mild to moderate AS is not well studied.

Methods

We included 1,434 patients with mild to moderate AS from the SEAS Study (Simvastatin and Ezetimibe in Aortic Stenosis) without AF or clinically overt heart failure at baseline. The primary endpoint for this substudy was time to incident AF, as determined by the first annual in-study 12-lead ECG with AF. Multivariable Cox model were adjusted for other important predictors of incident AF as selected by Bayesian statistics. Fine and Gray competing risk regression was used to evaluate the influence of all-cause mortality on selected predictor variables of incident AF.

Results

During a median follow-up of 4.3 years (range 0.1–6.9 years), incident AF occurred in 114 (6.1%) patients (13.8 per 1,000 person-years of follow-up), who at baseline were older (69±10 vs. 67±10 years, p<0.001), had larger systolic left atrial diameter (46±24 vs. 34±18 mm, p<0.001) and higher NT-proBNP level (286 [132; 613] vs. 154 [82; 297] pg/ml, p<0.001); but same left ventricular ejection fraction (66±6 mm vs. 67±6, p=0.4). In multivariable Cox regression, adjusted for age, circumferential end-systolic stress, left atrial volume and ECG PR interval, Ln(NT-proBNP) was associated with higher risk of new-onset AF (HR: 1.9 [95% CI: 1.6–2.3], p<0.001). Similar results were found when using Fine and Gray estimates with all-cause mortality (HR: 2.0 [95% CI: 1.7–2.4], p<0.001 (Figure, panel A). NT-proBNP level added incremental predictive information on incident AF over the other important, as selected by Bayesian statistics, predictor variables (C-index 0.81, p<0.001, Figure, panel B). There was no interaction with aortic valve area (p>0.05).

Figure 1

Conclusions

In patients with asymptomatic aortic stenosis and sinus rhythm at baseline, NT-proBNP levels were significantly higher in patients who subsequently developed AF. NT-proBNP significantly improved prognostic information of incident AF over other important predictor variables. This supports the notion that incident AF is a marker of left ventricular pressure overload and possibly a novel marker of timely intervention with aortic valve replacement.

Outcomes of surgery for post-cholecystectomy bile duct injuries: An audit from a tertiary referral center

AIM OF THE STUDY

Bile duct injury (BDI) after cholecystectomy is a serious complication. It often requires surgical repair. The aim of this study was to report on the short and long-term outcomes of surgery for post-cholecystectomy BDI.

PATIENTS AND METHODS

All the patients, who underwent surgery for post-cholecystectomy BDI between August 2007 and September 2017, were retrospectively reviewed. McDonald grading system was used to assess the long-term outcome. The risk factors for unsatisfactory long-term outcome were analyzed by univariate and multivatiate logistic regression analysis.

RESULTS

In total, 228 patients had a Roux-en-Y hepaticojejunostomy. Open cholecystectomy was the major cause of BDI (61%). The median time from injury to definitive repair was 6 months. The types of BDI were as follows: E1 in 13 (5.7%), E2 in 68 (29.82%), E3 in 108 (47.36%), E4 in 28 (12.28%), and E5 in 11 (4.82%) patients respectively. Postoperative morbidity and mortality were 25% and 1.31% respectively. After a median follow-up of 58 months, 90% patients had excellent to good outcome. Recurrent stricture developed in 6 (3%) patients. On multivariate analysis, long injury-repair interval and previous attempt at repair were independent predictors for unsatisfactory long-term outcome.

CONCLUSION

Surgical reconstruction affords excellent to good results for majority of the patients with post-cholecystectomy BDI. As longer delay in definitive repair and previous attempt at repair were associated with unsatisfactory long-term outcome, early referral to a specialized hepatobiliary surgery unit is recommended.

A23 Population level diversification of hepatitis C viral strains over time among people who inject drugs in Baltimore, MD

Hepatitis C virus (HCV) infection occurs in 30–90 per cent of people who inject drugs (PWID). Although cure rates can exceed 95 per cent, treatment access is limited and approximately 400,000 people die each year due to complications of chronic infection. A temporal analysis of cluster networks among PWID can be used to inform strategies to interdict transmission. In Baltimore, PWID have been recruited for The AIDS Linked to the IntraVenous Experience (ALIVE) cohort. A demographic questionnaire was administered and recorded for baseline and recent participants. Viral RNA underwent PCR with primers targeting the core and envelope-1 protein (CE1) and sequenced via Sanger sequencing. Sequences with > 400 bp reads and Q-scores >370 were used for downstream analysis resulting in 322 ALIVE baseline participants (1988–9) and 548 recently diagnosed subjects enrolled approximately two decades later (2005–16). Cluster networks were rendered with a threshold of 4 per cent in MicrobeTRACE, and statistical analyses were performed in R Studio. Of the 1988–9 subjects, the majority (259/317, 81.7%) were a part of cluster. There were nine clusters and fifty-eight singletons, with two large clusters containing most sequences of genotype 1a (73.5%). Two decades later, a minority of recently diagnosed individuals (235/512, 44.1%) were part of a cluster. There were seventeen clusters with 286 singletons with two large clusters containing 1a genotype individuals (21.5%). Additional clustering was done by parsing the two datasets by subtype 1a (n = 714) and 1b (n = 151). The genotype 1a network demonstrates a majority, 65.8 per cent, of participants in clusters. Moreover, two large clusters can be observed with baseline participants towards the center and recent participants on the outskirts indicative of high linkage at baseline. The genotype 1b network produced a single large cluster but subclusters were observed. The sequences between the two time points co-mingled but subclusters were also observed. Interestingly, the two large clusters from 1988 to 1989 were still evident in the 2005–16 viral sequences. We observed greater cluster diversity in more recently diagnosed individuals, indicative of a less connected network of individuals sharing transmission risk, though major viral strains did persist over time in this cohort.

One-Dimensional Quasicrystals with Power-Law Hopping

One-dimensional quasiperiodic systems with power-law hopping, 1/r^{a}, differ from both the standard Aubry-André (AA) model and from power-law systems with uncorrelated disorder. Whereas in the AA model all single-particle states undergo a transition from ergodic to localized at a critical quasidisorder strength, short-range power-law hops with a>1 can result in mobility edges. We find that there is no localization for long-range hops with a≤1, in contrast to the case of uncorrelated disorder. Systems with long-range hops rather present ergodic-to-multifractal edges and a phase transition from ergodic to multifractal (extended but nonergodic) states. Both mobility and ergodic-to-multifractal edges may be clearly revealed in experiments on expansion dynamics.

Establishment of a clinically relevant large animal model to assess the healing of metaphyseal bone

Despite the high incidence of metaphyseal bone fractures in patients, the mechanisms underlying the healing processes are poorly understood due to the lack of suitable experimental animal models. Hence, the present study was conducted to establish and characterise a clinically relevant large-animal model for metaphyseal bone healing. Six female adult Merino sheep underwent full wedge-shaped osteotomy at the distal left femur metaphysis. The osteotomy was stabilised internally with a customised anatomical locking titanium plate that allowed immediate post-operative full-weight bearing. Bone healing was evaluated at 12 weeks post-fracture relative to the untouched right femur. Histological and quantitative micro-computed tomography results revealed an increased mineralised bone mass with a rich bone microarchitecture. New trabeculae healed by direct intramembranous ossification, without callus and cartilaginous tissue formation. Stiffness at the cortical and trabecular regions was comparable in both groups. Functional morphological analysis of the osteocyte lacunae revealed regularly arranged spherically shaped lacunae along with the canalicular network. Bone surface biochemical analysis using time-of-flight secondary-ion mass spectrometry showed high and homogeneously distributed levels of calcium and collagenous components. Ultrastructure imaging of the new trabeculae revealed a characteristic parallel arrangement of the collagen fibrils, evenly mineralised by the dense mineral substance. The specialised bone cells were also characterised by their unique structural features. Bone remodelling in the fractured femur was evident in the higher expression levels of prominent bone formation and resorption genes. In conclusion, the novel metaphyseal fracture model is beneficial for studying healing and treatment options for the enhancement of metaphyseal bone defects.

Interplay of cold shock protein E with an uncharacterized protein, YciF, lowers porin expression and enhances bile resistance in Salmonella Typhimurium

Bacterial cold shock proteins (CSPs) function as RNA chaperones. To assess CSP's roles in the intracellular human pathogen Salmonella Typhimurium, we analyzed their expression in varied stress conditions. We found that cold shock protein E (cspE or STM14_0732) is up-regulated during bile salt-induced stress and that an S. Typhimurium strain lacking cspE (ΔcspE) displays dose-dependent sensitivity to bile salts, specifically to deoxycholate. We also found that an uncharacterized gene, yciF (STM14_2092), is up-regulated in response to bile stress in WT but not in the ΔcspE strain. Complementation with WT CspE, but not with a F30V CspE variant, abrogated the bile sensitivity of ΔcspE as did multicopy overexpression of yciF. Northern blotting experiments with rifampicin disclosed that the regulation of yciF expression is, most likely, due to the RNA-stabilizing activity of CspE. Importantly, electrophoretic mobility shift assays indicated that purified CspE, but not the F30V variant, directly binds yciF mRNA. We also observed that the extra-cytoplasmic stress-response (ESR) pathway is augmented in the bile-treated ΔcspE strain, as judged by induction of RpoE regulon genes (rpoE, degP, and rybB) and downstream ESR genes (hfq, rne, and PNPase). Moreover, the transcript levels of the porin genes, ompD, ompF, and ompC, were higher in bile salts-stressed ΔcspE and correlated with higher intracellular accumulation of the fluorescent DNA stain bisBenzimide H 33258, indicating greater cell permeability. In conclusion, our study has identified YciF, a CspE target involved in the regulation of porins and in countering bile stress in S. Typhimurium.

Zika and travel in the news: a content analysis of US news stories during the outbreak in 2016-2017

OBJECTIVES

This study aimed to understand what information the US media communicated about Zika virus (ZIKV) and travel in 2016 and 2017.

STUDY DESIGN

We conducted a content analysis of news coverage about ZIKV and travel from April 5, 2016 to March 31, 2017.

METHODS

We obtained a stratified, random sample of English language, US print newspaper and television news coverage about ZIKV and travel. We developed a coding scheme to assess key messages in the news, including how ZIKV is transmitted, the symptoms and outcomes of ZIKV infection, and recommended prevention behaviors.

RESULTS

Almost all news stories mentioned mosquito-borne transmission (96.8%) and just over half mentioned sexual transmission (55.3%). News stories were more likely to talk about ZIKV outcomes (78.8%) than ZIKV symptoms (40.6%). However, outcomes affecting babies were mentioned more frequently than outcomes affecting adults. Recommendations included a wide array of protective behaviors, such as delaying or avoiding travel (77.6%) and using mosquito repellent (41.0%). However, few studies (10.9%) mentioned barriers to practicing ZIKV prevention behaviors.

CONCLUSIONS

Public health organizations and professionals can use these findings to help improve communication about future outbreaks of mosquito-borne illnesses. We also recommend conducting real-time monitoring of news media and frequent content analysis of news stories to ensure coverage provides the information the public needs.

Post hepatectomy liver failure - A comprehensive review of current concepts and controversies

Post hepatectomy liver failure (PHLF) comprises of a conundrum of symptoms and signs following major hepatic resections. The pathophysiology essentially revolves around disruption of the normal hepatocyte regeneration and disturbed liver homeostasis. Prompt identification of the pre-operative predictors of PHLF in the form of biochemical parameters and imaging features are of paramount importance for any hepatic surgeon and forms the cornerstone of its management. Treatment revolves around a goal-directed resuscitation of the systemic organ failure. Auxiliary support systems such as liver dialysis devices and stem cell therapy are still under investigational trials for treatment of the same. Orthotopic liver transplantation (OLT) is the last resort in most cases not responding to other measures.

The ASOS Surgical Risk Calculator: development and validation of a tool for identifying African surgical patients at risk of severe postoperative complications

BACKGROUND

The African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. Existing risk assessment tools are not valid for use in this population because the pattern of risk for poor outcomes differs from high-income countries. The objective of this study was to derive and validate a simple, preoperative risk stratification tool to identify African surgical patients at risk for in-hospital postoperative mortality and severe complications.

METHODS

ASOS was a 7-day prospective cohort study of adult patients undergoing surgery in Africa. The ASOS Surgical Risk Calculator was constructed with a multivariable logistic regression model for the outcome of in-hospital mortality and severe postoperative complications. The following preoperative risk factors were entered into the model; age, sex, smoking status, ASA physical status, preoperative chronic comorbid conditions, indication for surgery, urgency, severity, and type of surgery.

RESULTS

The model was derived from 8799 patients from 168 African hospitals. The composite outcome of severe postoperative complications and death occurred in 423/8799 (4.8%) patients. The ASOS Surgical Risk Calculator includes the following risk factors: age, ASA physical status, indication for surgery, urgency, severity, and type of surgery. The model showed good discrimination with an area under the receiver operating characteristic curve of 0.805 and good calibration with c-statistic corrected for optimism of 0.784.

CONCLUSIONS

This simple preoperative risk calculator could be used to identify high-risk surgical patients in African hospitals and facilitate increased postoperative surveillance.

CLINICAL TRIAL REGISTRATION

NCT03044899.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Effects of CO2 enrichment on metal bioavailability and bioaccumulation using Mytilus galloprovincialis

The main aim of this study was to evaluate the bioavailability of metals related to CO₂ enrichment on the mussels Mytilus galloprovincialis by metal's bioaccumulation analysis. Two sediment samples were selected and subjected to different pH levels. Concentrations of metals were measured in the overlying seawater and in the whole body of mussels exposed on the 7th, 14th and 21st days. Results showed that the CO₂ enrichment in aquatic ecosystems cause significant (p < 0.05) changes on the concentrations of Cu, Zn, Ni, Mn and As between the control pH and pH 7.0 after 7 days of exposure; and in the concentration of Fe at pH 6.0 using the RSP sediment. The multivariate analysis results showed that the increase in the bioaccumulation of some metals in mussels was linked to the acidification. It was concluded that many factors may interfere in the results when the acidification and bioavailability of metals are inquired.