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Although there are no approved countermeasures available to prevent or treat disease caused by Marburg virus (MARV), potently neutralizing monoclonal antibodies (mAbs) derived from B cells of human survivors have been identified. One such mAb, MR191, has been shown to provide complete protection against MARV in nonhuman primates. We previously demonstrated that prophylactic administration of an adeno-associated virus (AAV) expressing MR191 protected mice from MARV. Here, we modified the AAV-MR191 coding sequence to enhance efficacy and reevaluated protection in a guinea pig model. Remarkably, 4 different variants of AAV-MR191 provided complete protection against MARV, despite administration 90 days prior to challenge. Based on superior expression kinetics, AAV-MR191-io2, was selected for evaluation in a dose-reduction experiment. The highest dose provided 100% protection, while a lower dose provided ∼88% protection. These data confirm the efficacy of AAV-mediated expression of MR191 and support the further development of this promising MARV countermeasure. [ABSTRACT FROM AUTHOR]

The transcriptional regulatory machinery in mitochondrial bioenergetics is complex and is still not completely understood. We previously demonstrated that the histone methyltransferase Smyd1 regulates mitochondrial energetics. Here, we identified Perm1 (PPARGC-1 and ESRR-induced regulator, muscle specific 1) as a downstream target of Smyd1 through RNA-seq. Chromatin immunoprecipitation assay showed that Smyd1 directly interacts with the promoter of Perm1 in the mouse heart, and this interaction was significantly reduced in mouse hearts failing due to pressure overload for 4 weeks, where Perm1 was downregulated (24.4 ± 5.9% of sham, p<0.05). Similarly, the Perm1 protein level was significantly decreased in patients with advanced heart failure (55.2 ± 13.1% of donors, p<0.05). Phenylephrine (PE)-induced hypertrophic stress in cardiomyocytes also led to downregulation of Perm1 (55.7 ± 5.7% of control, p<0.05), and adenovirus-mediated overexpression of Perm1 rescued PE-induced downregulation of estrogen-related receptor alpha (ERRα), a key transcriptional regulator of mitochondrial energetics, and its target gene, Ndufv1 (Complex I). Pathway enrichment analysis of cardiomyocytes in which Perm1 was knocked-down by siRNA (siPerm1), revealed that the most downregulated pathway was metabolism. Cell stress tests using the Seahorse XF analyzer showed that basal respiration and ATP production were significantly reduced in siPerm1 cardiomyocytes (40.7% and 23.6% of scrambled-siRNA, respectively, both p<0.05). Luciferase reporter gene assay further revealed that Perm1 dose-dependently increased the promoter activity of the ERRα gene and known target of ERRα, Ndufv1 (Complex I). Overall, our study demonstrates that Perm1 is an essential regulator of cardiac energetics through ERRα, as part of the Smyd1 regulatory network. [ABSTRACT FROM AUTHOR]

Background: The advancement of AAV vectors into clinical testing has accelerated rapidly over the past two decades. While many of the AAV vectors being utilized in clinical trials are derived from natural serotypes, engineered serotypes are progressing toward clinical translation due to their enhanced tissue tropism and immune evasive properties. However, novel AAV vectors require formulation and stability testing to determine optimal storage conditions prior to their use in a clinical setting. Results: Here, we evaluated the thermal stability of AAV6.2FF, a rationally engineered capsid with strong tropism for lung and muscle, in two different buffer formulations; phosphate buffered saline (PBS), or PBS supplemented with 0.001% non-ionic surfactant Pluronic F68 (PF-68). Aliquots of AAV6.2FF vector encoding the firefly luciferase reporter gene (AAV6.2FF-ffLuc) were incubated at temperatures ranging from -20°C to 55°C for varying periods of time and the impact on infectivity and particle integrity evaluated. Additionally, the impact of several rounds of freeze-thaw treatments on the infectivity of AAV6.2FF was investigated. Vector infectivity was measured by quantifying firefly luciferase expression in HEK 293 cells and AAV particle integrity was measured by qPCR quantification of encapsidated viral DNA. Conclusions: Our data demonstrate that formulating AAV6.2FF in PBS containing 0.001% PF-68 leads to increased stability and particle integrity at temperatures between -20℃ to 21℃ and protection against the destructive effects of freeze-thaw. Finally, AAV6.2FF-GFP formulated in PBS supplemented with 0.001% PF-68 displayed higher transduction efficiency in vivo in murine lung epithelial cells following intranasal administration than vector buffered in PBS alone further demonstrating the beneficial properties of PF-68. [ABSTRACT FROM AUTHOR]

Regulation of breathing is critical to our capacity to accommodate deficits in oxygen availability and demand during, for example, sleep and ascent to altitude. It is generally accepted that a fall in arterial oxygen increases afferent discharge from the carotid bodies to the brainstem and thus delivers increased ventilatory drive, which restores oxygen supply and protects against hypoventilation and apnoea. However, the precise molecular mechanisms involved remain unclear. We recently identified as critical to this process the AMP-activated protein kinase (AMPK), which is key to the cell-autonomous regulation of metabolic homoeostasis. This observation is significant for many reasons, not least because recent studies suggest that the gene for the AMPK-α1 catalytic subunit has been subjected to natural selection in high-altitude populations. It would appear, therefore, that evolutionary pressures have led to AMPK being utilized to regulate oxygen delivery and thus energy supply to the body in the short, medium and longer term. Contrary to current consensus, however, our findings suggest that AMPK regulates ventilation at the level of the caudal brainstem, even when afferent input responses from the carotid body are normal. We therefore hypothesize that AMPK integrates local hypoxic stress at defined loci within the brainstem respiratory network with an index of peripheral hypoxic status, namely afferent chemosensory inputs. Allied to this, AMPK is critical to the control of hypoxic pulmonary vasoconstriction and thus ventilation-perfusion matching at the lungs and may also determine oxygen supply to the foetus by, for example, modulating utero-placental blood flow. [ABSTRACT FROM AUTHOR]

Key points Progression of hypoxic pulmonary hypertension is thought to be due, in part, to suppression of voltage-gated potassium channels (Kv) in pulmonary arterial smooth muscle by hypoxia, although the precise molecular mechanisms have been unclear., AMP-activated protein kinase (AMPK) has been proposed to couple inhibition of mitochondrial metabolism by hypoxia to acute hypoxic pulmonary vasoconstriction and progression of pulmonary hypertension., Inhibition of complex I of the mitochondrial electron transport chain activated AMPK and inhibited Kv1.5 channels in pulmonary arterial myocytes., AMPK activation by 5-aminoimidazole-4-carboxamide riboside, A769662 or C13 attenuated Kv1.5 currents in pulmonary arterial myocytes, and this effect was non-additive with respect to Kv1.5 inhibition by hypoxia and mitochondrial poisons., Recombinant AMPK phosphorylated recombinant human Kv1.5 channels in cell-free assays, and inhibited K+ currents when introduced into HEK 293 cells stably expressing Kv1.5., These results suggest that AMPK is the primary mediator of reductions in Kv1.5 channels following inhibition of mitochondrial oxidative phosphorylation during hypoxia and by mitochondrial poisons., Abstract Progression of hypoxic pulmonary hypertension is thought to be due, in part, to suppression of voltage-gated potassium channels (Kv) in pulmonary arterial smooth muscle cells that is mediated by the inhibition of mitochondrial oxidative phosphorylation. We sought to determine the role in this process of the AMP-activated protein kinase (AMPK), which is intimately coupled to mitochondrial function due to its activation by LKB1-dependent phosphorylation in response to increases in the cellular AMP:ATP and/or ADP:ATP ratios. Inhibition of complex I of the mitochondrial electron transport chain using phenformin activated AMPK and inhibited Kv currents in pulmonary arterial myocytes, consistent with previously reported effects of mitochondrial inhibitors. Myocyte Kv currents were also markedly inhibited upon AMPK activation by A769662, 5-aminoimidazole-4-carboxamide riboside and C13 and by intracellular dialysis from a patch-pipette of activated (thiophosphorylated) recombinant AMPK heterotrimers (α2β2γ1 or α1β1γ1). Hypoxia and inhibitors of mitochondrial oxidative phosphorylation reduced AMPK-sensitive K+ currents, which were also blocked by the selective Kv1.5 channel inhibitor diphenyl phosphine oxide-1 but unaffected by the presence of the BKCa channel blocker paxilline. Moreover, recombinant human Kv1.5 channels were phosphorylated by AMPK in cell-free assays, and K+ currents carried by Kv1.5 stably expressed in HEK 293 cells were inhibited by intracellular dialysis of AMPK heterotrimers and by A769662, the effects of which were blocked by compound C. We conclude that AMPK mediates Kv channel inhibition by hypoxia in pulmonary arterial myocytes, at least in part, through phosphorylation of Kv1.5 and/or an associated protein. [ABSTRACT FROM AUTHOR]

This study presents a descriptive-analytical argument for exploring the concept of definiteness in Arabic adopting Chesterman's theory of definiteness as a scalar and non-binary system. It investigates the meanings and functions of the Arabic article al- focusing on the divergent nature of definiteness as indicated by this article. Results have shown that al- has different meanings which serve various functions of which definiteness is only one. It has three distinct structures (a) nominal al- (al al-mawṣūla) which functions as a relative noun, (b) an article of definiteness (al al-ta'rīf) and (c) augmented al- (al al-zā'ida). When used as a definite article, al- does not always indicate true definiteness; it can be used pragmatically to indicate verbal 'non-referential' definiteness (ta'rīf lafẓī) equal to what Chesterman refers to as 'inclusiveness' as an area of opposition in definiteness. This paper concludes that definiteness in Arabic is a scalar rather than a bi-polar concept where al- does serve, though not in all cases, as an article of definiteness. The oppositions indicated in the way definiteness are linguistically encoded and semantically decoded by Arabic definiteness constructions in general, and those indicated by the Arabic article al- in particular, are not discrete but scalar. It is recommended that definiteness is viewed as a continuum of scales and degrees depending on contextual pragmatic factors. [ABSTRACT FROM AUTHOR]

The integrity of sperm DNA is vital for successful fertilization and genetic transmission to offspring. Yet, oxidative stress is a threat to this integrity. Our study aims to explore the effect of antioxidants on DNA integrity, and their implications for male fertility. The study was designed as a double blind, placebo controlled, clinical trial. From April 2020 to January 2023, a total of 263 partients with idiopathic infertility were selected and randomized into two groups: 131 participants received a combination of antioxidants, while 132 participants received a placebo. For each patient, we performed a TUNEL assay for sperm DNA fragmentation and an aniline blue staining for sperm chromatin decondensation initially prior to administering treatment, and then again after three months of treatment. The average age of patients was 38.94 ± 5.8 years. The two groups had comparable baseline characteristics. After 3 months of treatment, the DNA fragmentation index (DFI) decreased significantly within each group (p<0.001), but this variation was without significant difference between the two groups. An analysis of these results according to the initial DFI enabled us to define the cut-off point for significant improvement in sperm DNA fragmentation under treatment, at 20%. In fact, only patients with an initial fragmentation rate greater than or equal to 20% had a significant reduction in DFI after 3 months of antioxydant treatment. This significant difference was found respectively in the subgroup with initial DFI between 20 and 25% (p=0.002) and the subgroup with initial DFI >25% (p<=0.001). When comparing initial and final values of sperm chromatin decondensation rate, a decrease was found after 3 months of treatment only in the antioxidant group, with no statistically significant difference. Importantly, the rate of sperm chromatin decondensation increased after 3 months in the placebo group. On the other hand, no significant difference was found between the treatment and placebo groups after 3 months of treatment. In summary, our findings suggest that a three month antioxidant supplementation could reduce DNA fragmentation in patients with idiopathic infertility, but do not affect chromatin decondensation. Further investigation is necessary for optimizing therapeutic strategies to improve male fertility. [ABSTRACT FROM AUTHOR]

Introduction: Understanding adolescents perceptions of their weight status and the factors influencing these perceptions is pivotal for developing targeted interventions and policies to counteract the rising obesity trends. Objectives: This cross-sectional study aimed to determine the accuracy of weight status perceptions among Tunisian adolescents compared to objective metrics and to identify sociodemographic characteristics and life habits associated with the underestimation of weight status. Methods: A cross-sectional, school-based study was conducted among a randomized sample of adolescents attending secondary schools in Sousse, Tunisia. A total of 1399 students participated, with anthropometric measurements taken, and a pre-tested Arabic questionnaire administered to gather sociodemographic data and perceived weight status, assessed using the Figure Rating Scale (FRS). The accuracy of perceived weight status was determined by comparing the measured weight status with participants; self-reported perceptions. We evaluated the association between body weight distortion and life habits which included regular physical activity, screen time (time spent on internet per day), number of fruits and vegetables consumed per day, and fast-food consumption. Results: The study achieved an 86.68% response rate, with over half of the participants being female (60.5%), and the average age being 17 years. The majority of adolescents (41%) perceived themselves as having normal body weight, while 34.5% perceived themselves as underweight, 16.6% as overweight, and 7.9% as obese. However, based on BMI categories, 72.6% had a normal measured weight, 20.4% were overweight, and 6.9% were obese. A substantial proportion of participants (45.6%) underestimated their weight status, with a significant proportion being objectively overweight or obese (26%). Furthermore, we found a significant association between the perception of weight accuracy with four correlates: gender, mother educational level, regular physical activity, and the number of fruits and vegetables consumed per day. Conclusions: The findings revealed a disparity between perceived and actual weight status among Tunisian adolescents, with a significant underestimation of weight status, particularly among those who are overweight or obese. The results highlighted the crucial need for interventions that address weight perception inaccuracies and promote healthy weight awareness and management among adolescents in Tunisia. The study underscored the importance of further research to understand the development and progression of body weight underestimation throughout adolescence and the roles of lifestyle behaviors in shaping weight perceptions. Disclosure of Interest: None Declared [ABSTRACT FROM AUTHOR]

Introduction: Despite extensive studies of the impact of COVID-19 on patients with cancer, there is a dearth of information from the Middle East and North Africa (MENA) region. Our study aimed to report pertinent MENA COVID-19 and Cancer Registry (MCCR) findings on patient management and outcomes. Methods: MCCR was adapted from the American Society of Clinical Oncology COVID-19 Registry to collect data specifically from patients with cancer and SARS-CoV-2 infection from 12 centers in eight countries including Saudi Arabia, Jordan, Lebanon, Turkey, Egypt, Algeria, United Arab Emirates, and Morocco. The Registry included data on patients and disease characteristics, treatment, and patient outcomes. Logistic regression was used to assess associations with mortality. Results: Between November 29, 2020, and June 8, 2021, data were captured on 2008 patients diagnosed with COVID-19 from the beginning of the pandemic. Median age was 56 years (16–98), 56.4% were females, and 26% were current or ex-smokers. Breast cancer (28.5%) was the leading diagnosis and 50.5% had metastatic disease. Delays of planned treatment (.14 days) occurred in 80.3% for surgery, 48.8% for radiation therapy, and 32.9% for systemic therapy. Significant reduction in the delays of all three treatment modalities occurred after June 1, 2020. All-cause mortality rates at 30 and 90 days were 17.1% and 23.4%, respectively. All-cause mortality rates at 30 days did not change significantly after June 1, 2020; however, 90-day mortality increased from 33.4% to 42.9% before and after that date (p ¼ 0.015). Multivariable regression analysis showed the following predictors of higher 30- and 90-day mortality: age older than 70 years, having metastatic disease, disease progression, and being off chemotherapy. Conclusion: Patients with cancer in the MENA region experienced similar risks and outcome of COVID-19 as reported in other populations. Although there were fewer treatment delays after June 1, 2020, 90-day mortality increased, which may be attributed to other risk factors such as disease progression or new patients who presented with more advanced disease. [ABSTRACT FROM AUTHOR]

The hypoxic ventilatory response (HVR) is critical to breathing and thus oxygen supply to the body and is primarily mediated by the carotid bodies. Here we reveal that carotid body afferent discharge during hypoxia and hypercapnia is determined by the expression of Liver Kinase B1 (LKB1), the principal kinase that activates the AMP-activated protein kinase (AMPK) during metabolic stresses. Conversely, conditional deletion in catecholaminergic cells of AMPK had no effect on carotid body responses to hypoxia or hypercapnia. By contrast, the HVR was attenuated by LKB1 and AMPK deletion. However, in LKB1 knockouts hypoxia evoked hypoventilation, apnoea and Cheyne-Stokes-like breathing, while only hypoventilation and apnoea were observed after AMPK deletion. We therefore identify LKB1 as an essential regulator of carotid body chemosensing and uncover a divergence in dependency on LKB1 and AMPK between the carotid body on one hand and the HVR on the other. Unlike AMPK, Liver kinase B1 (LBK1) is required for carotid body chemosensing and the hypoxic ventilatory response. Moreover, loss of LBK1, but not AMPK, provokes Cheyne-Stokes-like breathing during hypoxia, which is associated with heart failure. [ABSTRACT FROM AUTHOR]

The "stress" kinases cAMP-dependent protein kinase (PKA) and calcium/calmodulin-dependent protein kinase II (CaMKII), phosphorylate the Na+ channel Nav1.5 subunit to regulate its function. However, how the channel regulation translates to ventricular conduction is poorly understood. We hypothesized that the stress kinases positively and differentially regulate conduction in the right (RV) and the left (LV) ventricles. We applied the CaMKII blocker KN93 (2.75 μM), PKA blocker H89 (10 μM), and broadacting phosphatase blocker calyculin (30 nM) in rabbit hearts paced at a cycle length (CL) of 150-8,000 ms. We used optical mapping to determine the distribution of local conduction delays (inverse of conduction velocity). Control hearts exhibited constant and uniform conduction at all tested CLs. Calyculin (15-min perfusion) accelerated conduction, with greater effect in the RV (by 15.3%) than in the LV (by 4.1%; P < 0.05). In contrast, both KN93 and H89 slowed down conduction in a chamber-, time-, and CL-dependent manner, with the strongest effect in the RV outflow tract (RVOT). Combined KN93 and H89 synergistically promoted conduction slowing in the RV (KN93: 24.7%; H89: 29.9%; and KN93 + H89: 114.2%; P < 0.0016) but not the LV. The progressive depression of RV conduction led to conduction block and reentrant arrhythmias. Protein expression levels of both the CaMKII-δ isoform and the PKA catalytic subunit were higher in the RVOT than in the apical LV (P < 0.05). Thus normal RV conduction requires a proper balance between kinase and phosphatase activity. Dysregulation of this balance due to pharmacological interventions or disease is potentially proarrhythmic. [ABSTRACT FROM AUTHOR]

Smyd1, a muscle-specific histone methyltransferase, has established roles in skeletal and cardiac muscle development, but its role in the adult heart remains poorly understood. Our prior work demonstrated that cardiac-specific deletion of Smyd1 in adult mice (Smyd1-KO) leads to hypertrophy and heart failure. Here we show that down-regulation of mitochondrial energetics is an early event in these Smyd1-KO mice preceding the onset of structural abnormalities. This early impairment of mitochondrial energetics in Smyd1-KO mice is associated with a significant reduction in gene and protein expression of PGC-1α, PPARα, and RXRα, the master regulators of cardiac energetics. The effect of Smyd1 on PGC-1α was recapitulated in primary cultured rat ventricular myocytes, in which acute siRNA-mediated silencing of Smyd1 resulted in a greater than twofold decrease in PGC-1α expression without affecting that of PPARα or RXRα. In addition, enrichment of histone H3 lysine 4 trimethylation (a mark of gene activation) at the PGC-1α locus was markedly reduced in Smyd1-KO mice, and Smyd1-induced transcriptional activation of PGC-1α was confirmed by luciferase reporter assays. Functional confirmation of Smyd1's involvement showed an increase in mitochondrial respiration capacity induced by overexpression of Smyd1, which was abolished by siRNA-mediated PGC-1α knockdown. Conversely, overexpression of PGC-1α rescued transcript expression and mitochondrial respiration caused by silencing Smyd1 in cardiomyocytes. These findings provide functional evidence for a role of Smyd1, or any member of the Smyd family, in regulating cardiac energetics in the adult heart, which is mediated, at least in part, via modulating PGC-1α. [ABSTRACT FROM AUTHOR]

In Tunisia, there are about 478 species of plants commonly used in folk medicine. Medicinal plants and herbal remedies used are responsible for 2% of intoxications listed by Tunisian National Poison Center. Most cases are related to confusion between edible plants and toxic plants lookalikes or to an excessive consumption of therapeutic plants. We report the case of a 58-year-old man admitted to the Emergency Department of the Regional Hospital of Zaghouan (Tunisia), with renal failure and rhabdomyolysis. The patient reported having daily consumption of a homemade tea based on Mediterranean Buckthorn roots, during the last 6 months to treat type 2 diabetes. The aim of this work was to establish an association between the consumption of the herbal remedy and the occurrence of both renal failure and rhabdomyolysis. No similar cases have been reported in recent literature. [ABSTRACT FROM AUTHOR]

Introduction In spite of the international consensus on the human health risks associated with exposure to persistent organic pollutants (POPs), the Tunisian population is suspected to have been inadvertently exposed to POPs over the last decades. Objectives The aim of this study was to evaluate POP concentrations in the serum of a subset of 54 Tunisian women and to identify some socio-demographic and dietary predictors of exposure to POPs. Results Of the ten POPs analyzed, three polychlorinated biphenyl (PCB) congeners (-138, -153 and -180), and two organochlorine pesticides (OCPs), HCB and p,p ′-DDE, showed frequencies ranging from 98 to 100%. Serum median concentrations of PCB congeners (-138, -153 PCB-180) were 26.08, 119.1 and 29.84 ng/g lipid, respectively, and median concentrations of HCB and p,p ′-DDE were 19.98 and 127.59 ng/g lipid, respectively. Age was positively correlated with serum levels of selected POPs. Women living in northern Tunisia showed higher serum levels of all PCBs. Working outside home and cereal consumption were positively associated to serum levels of p,p ′-DDE. The duration of the lactation was also related to lower serum levels of p,p ′-DDE and HCB. Conclusion The levels of exposure to POPs found warrant a biomonitoring program in order to identify routes of exposure and population groups at higher risk. This program will help to establish prevention policies and to determine the association between exposure to POPs and chronic diseases. [ABSTRACT FROM AUTHOR]