Cobalt ions induce a cellular senescence secretory phenotype in human synovial fibroblast-like cells that may be an early event in the development of adverse local tissue reactions to hip implants.

Objectives: Total hip arthroplasty is a successful procedure for treating advanced osteoarthritis (OA). Metal bearing surfaces remain one of the most widely implanted prosthesis, however approximately 10% of patients develop adverse local tissue reactions (ALTRs), namely lymphocytic predominant soft tissue reaction with or without necrosis and osteolysis resulting in high revision rates. The mechanism(s) for these reactions remains unclear although T lymphocyte mediated type IV hypersensitivity to cobalt (Co) and chromium (Cr) ions have been described. The purpose of this study was to determine the prolonged effects of Co and Cr metal ions on synovial fibroblasts to better understand the impact of the synovial membrane in the development of ALTRs. Methods: Human synovial fibroblast-like cells were isolated from donors undergoing arthroplasty. DNA content and Alamar blue assay were used to determine cellular viability against exposure to Co and Cr. A beta-galactosidase assay was used to determine the development of cellular senescence. Western blotting and RT-qPCR were employed to determine changes in senescent associated secretory factors, signaling and anti-oxidant enzyme expression. A fluorescent assay was used to measure accumulation of hydrogen peroxide. Results: We demonstrate that prolonged cobalt exposure results in a downregulation of the enzyme catalase resulting in cytosolic accumulation of hydrogen peroxide, decreased Akt activity and cellular senescence. Senescent fibroblasts demonstrated upregulation of proinflammatory cytokines IL-1ß and TNFα in addition to the neurotrophic factor NGF. Conclusion: Our results provide evidence that metal ions induce a senescent associated secretory phenotype in synovial fibroblasts that could contribute to the development of adverse local tissue reactions.

Factors associated with early postoperative mortality after total anomalous pulmonary venous connection repair: A retrospective cohort study.

Total anomalous pulmonary venous connection (TAPVC) is a rare congenital defect where pulmonary venous plexus fails to connect with the left atrium (LA). Surgical repair is the primary treatment for TAPVC, but factors influencing outcomes are not fully understood. This study investigates the early outcomes of surgical repair for TAPVC and associated factors. A retrospective cohort analysis was conducted on TAPVC patients who underwent surgical repair between 2012 and 2022. Data were collected from medical records and supplemented with phone call validation. Demographic characteristics, surgical data, diagnostic tests, and outcomes were analyzed. Statistical analysis included chi-square, t-tests, and multivariate logistic regression using SPSS. A total of 88 patients underwent surgical repair for TAPVC, resulting in a mortality rate of 21.6%. Weight and bypass time were significantly associated with patient survival. Female patients had a higher likelihood of death. The anatomic type did not significantly influence mortality. Patients with pulmonary venous obstruction (PVO) experienced a higher mortality rate. Notably, ligation of the vertical vein in supracardiac and infracardiac types was associated with lower mortality. In conclusion, our study identifies several key factors contributing to higher mortality rates following TAPVC surgery, including low weight, female gender, prolonged bypass time, and preoperative vein obstruction. Highlighting the significance of surgical technique, particularly the sutureless approach, we advocate for its meticulous consideration to achieve improved outcomes. Furthermore, our findings indicate a potential decrease in mortality associated with vertical vein ligation, which may mitigate the risk of post-repair heart failure. We suggest further rigorous studies to gain comprehensive insights into TAPVC surgical interventions.

The Determinants of Household Food Waste Generation and its Associated Caloric and Nutrient Losses: The Case of Lebanon.

Food waste has a great impact on food and nutrition security, the environment, and global, regional as well as national economies. However, little is known about the associated nutrient loss embedded in wasted foods, especially in developing countries, with Lebanon being a case in point. The present paper uses data gathered from a survey of 250 households conducted in Beirut, Lebanon, in which respondents filled 7-day food waste diaries in order to investigate the drivers of food waste generation at the household level and its dietary content. The results show that food waste is approximately 0.2 kg per capita per day in urban Lebanon. This wasted food contains on average 451.2 kcal, 37.5 g carbohydrates, 14.9 g protein, 2.9 g dietary fiber, 2.4 µg vitamin D, 165.2 mg calcium and 343.2 mg potassium. Furthermore, a Tobit analysis of the socio-demographic and behavioral drivers of food waste generation was conducted. This analysis shows that being the sole homeowner, spending more on food, having a larger number of household members, being ready to eat everything prepared, and tending not to buy special offers, significantly increases household food waste generation, at least in terms of physical weight. This is the first study conducted in Lebanon and the Middle East aiming at investigating food waste, and the associated nutrient loss as well as the drivers of food waste generation at the household level. This work could help provide evidence for policymakers to address both food and nutrition security issues in Lebanon.

Extended-spectrum beta-lactamase (ESBL)- and carbapenemase-producing Enterobacteriaceae in water sources in Lebanon.

Extended-spectrum beta-lactamases (ESBLs) have been recurrently reported in both human and veterinary medicine, and carbapenemases have also emerged in these two sectors. Such resistance phenotypes were increasingly reported in the environment, which both receives and further disseminates multidrug-resistant (MDR) bacteria. Here, we report the high contamination of water samples (68.2%; 15/22) collected in estuaries in Lebanon. From these 15 contaminated sites, a total of 21 ESBL-producing (mostly harbouring the blaCTX-M-15 gene) and four carbapenemase-producing (two blaOXA-48 and two blaOXA-244) Enterobacteriaceae were recovered. ESBL contamination was also identified in water samples collected from rural wells and spring water, although at a lower frequency. Indeed, 1.9% (3/155) and 6.1% (7/115) of the wells and springs were contaminated, respectively, and all identified isolates were CTX-M-15-producing E. coli. Interestingly, sequence types (STs) previously associated both with animal and human reservoirs were detected (ST38, ST10 and ST131), suggesting a complex source of contamination. This situation is alarming since water drawn from wells or springs is directly intended for human consumption in Lebanon without any further treatment. Moreover, even though water from estuaries is not intended for human consumption, it is used to water animals and irrigate crops. Consequently, water contamination by ESBLs and carbapenemases in Lebanon is potentially a major risk to public health. Part of this work was presented at the 7th Symposium on Antimicrobial Resistance in Animals and the Environment (ARAE).

OXA-48 and CTX-M-15 extended-spectrum beta-lactamases in raw milk in Lebanon: epidemic spread of dominant Klebsiella pneumoniae clones.

Raw milk has recently been reported as a source of extended-spectrum beta-lactamase (ESBL) and carbapenemase genes. We thus investigated the prevalence of ESBL- and carbapenemase-producing Enterobacteriaceae in raw milk in Lebanon in order to assess the risk of transfer of these bacteria to humans. A high prevalence (30.2 %) of CTX-M-15-producing K. pneumoniae was detected in raw bovine milk. Three main K. pneumoniae clones were identified by PFGE and MLST typing. Southern blot experiments revealed that one of these clones carried the blaCTX-M-15 gene chromosomally. Moreover, one OXA-48-producing K. pneumoniae ST530 and seven CTX-M-15-producing Escherichia coli sharing the same ST were also detected. These findings highlight the spread of dominant CTX-M-15-producing K. pneumoniae clones and OXA-48-producing isolates in the food chain. Milk, which is mostly consumed raw in Lebanon, may be a source of human exposure to ESBLs and carbapenemases.

High Prevalence of Non-ST131 CTX-M-15-Producing Escherichia coli in Healthy Cattle in Lebanon.

Extended-Spectrum Beta-Lactamases (ESBL)-producing Escherichia coli have disseminated in both humans and animals worldwide. However, the ESBL epidemiology in these two reservoirs differs markedly, with CTX-M-15 frequently found in humans and CTX-M-1 preferentially found in animals. Our goal was to estimate the prevalence of fecal carriage of ESBL producers in cattle from 31 farms in Lebanon and to characterize the responsible enzymes. This prevalence was high (26/31, 84% of ESBL-positive farms), with a majority of isolates producing CTX-M-15 (27/40, 67.5%). Strikingly, this distribution is reminiscent of the human ESBL epidemiology, even though none of the bovine isolates belonged to the ST131 human clone. This is the first report of ESBL-producing E. coli in animals in Lebanon. Our data rather suggest the spread of CTX-M-15 plasmids in different E. coli backgrounds. Nonetheless, some CTX-M-15-producing E. coli clones found here have already been reported from animal, human, or environmental sources.

Unsupervised classification in uterine electromyography signal: toward the detection of preterm birth.

The purpose of this study is to classify the uterine contractions in the electromyography (EMG) signal. As the frequency content of the contraction changes from one woman to another and during the pregnancy, wavelet decomposition is used to extract the parameters of each contraction, and an unsupervised statistical classification method based on competitive artificial neural network is then used to classify events. A principal component analysis projection is then used to evidence the groups resulting from this classification. Results show that uterine contractions may be classified into independent groups according to their frequency content and so according to the pregnancy terms. This classification will be used to detect the preterm birth.