Ligand-free biodegradable poly(beta-amino ester) nanoparticles for targeted systemic delivery of mRNA to the lungs.

Non-viral nanoparticles (NPs) have seen heightened interest as a delivery method for a variety of clinically relevant nucleic acid cargoes in recent years. While much of the focus has been on lipid NPs, non-lipid NPs, including polymeric NPs, have the possibility of improved efficacy, safety, and targeting, especially to non-liver organs following systemic administration. A safe and effective systemic approach for intracellular delivery to the lungs could overcome limitations to intratracheal/intranasal delivery of NPs and improve clinical benefit for a range of diseases including cystic fibrosis. Here, engineered biodegradable poly (beta-amino ester) (PBAE) NPs are shown to facilitate efficient delivery of mRNA to primary human airway epithelial cells from both healthy donors and individuals with cystic fibrosis. Optimized NP formulations made with differentially endcapped PBAEs and systemically administered in vivo lead to high expression of mRNA within the lungs in BALB/c and C57 B/L mice without requiring a complex targeting ligand. High levels of mRNA-based gene editing were achieved in an Ai9 mouse model across bronchial, epithelial, and endothelial cell populations. No toxicity was observed either acutely or over time, including after multiple systemic administrations of the NPs. The non-lipid biodegradable PBAE NPs demonstrate high levels of transfection in both primary human airway epithelial cells and in vivo editing of lung cell types that are targets for numerous life-limiting diseases particularly single gene disorders such as cystic fibrosis and surfactant deficiencies.

Differences in the Effect of Beta-Hydroxybutyrate on the Mitochondrial Biogenesis, Oxidative Stress and Inflammation Markers in Tissues from Young and Old Rats.

One of the therapeutic approaches to age-related diseases is modulation of body cell metabolism through certain diets or their pharmacological mimetics. The ketogenic diet significantly affects cell energy metabolism and functioning of mitochondria, which has been actively studied in various age-related pathologies. Here, we investigated the effect of the ketogenic diet mimetic beta-hydroxybutyrate (BHB) on the expression of genes regulating mitochondrial biogenesis (Ppargc1a, Nrf1, Tfam), quality control (Sqstm1), functioning of the antioxidant system (Nfe2l2, Gpx1, Gpx3, Srxn1, Txnrd2, Slc6a9, Slc7a11), and inflammatory response (Il1b, Tnf, Ptgs2, Gfap) in the brain, lungs, heart, liver, kidneys, and muscles of young and old rats. We also analyzed mitochondrial DNA (mtDNA) copy number, accumulation of mtDNA damage, and levels of oxidative stress based on the concentration of reduced glutathione and thiobarbituric acid-reactive substances (TBARS). In some organs, aging disrupted mitochondrial biogenesis and functioning of cell antioxidant system, which was accompanied by the increased oxidative stress and inflammation. Administration of BHB for 2 weeks had different effects on the organs of young and old rats. In particular, BHB upregulated expression of genes coding for proteins associated with the mitochondrial biogenesis and antioxidant system, especially in the liver and muscles of young (but not old) rats. At the same time, BHB contributed to the reduction of TBARS in the kidneys of old rats. Therefore, our study has shown that administration of ketone bodies significantly affected gene expression in organs, especially in young rats, by promoting mitochondrial biogenesis, improving the functioning of the antioxidant defense system, and partially reducing the level of oxidative stress. However, these changes were much less pronounced in old animals.

Pathophysiological characteristics of subjects with intermediate hyperglycemia and type 2 diabetes identified by 1-hour plasma glucose during an oral glucose tolerance test.

AIMS: The International Diabetes Federation (IDF) has recently recommended determination of 1-hour plasma glucose (1-hPG) during an oral glucose tolerance test (OGTT) to diagnose intermediate hyperglycemia (IH) and type 2 diabetes (T2DM). Herein, we investigated the cardiometabolic characteristics of individuals with IH and T2DM according to IDF criteria. METHODS: We studied 3086 individuals stratified on the basis of fasting, 1-hPG and 2-hPG in four groups: 1) normal glucose tolerance (NGT), 2) isolated impaired fasting glucose (iIFG,), 3) IH (fasting glucose < 126 mg/dL, 1-hPG 155-208 mg/dL, and/or 2-hPG 140-199 mg/dL, and 4) newly diagnosed T2DM (fasting glucose, 1-hPG and/or 2-hPG≥126 mg/dL, 209 mg/dL and 200 mg/dL, respectively). RESULTS: Individuals with IH and T2DM exhibited higher adiposity, blood pressure, uric acid, a worse lipid and inflammatory profile and a progressive reduction in Matsuda index of insulin sensitivity, insulinogenic index, and disposition index as compared to the NGT group. Moreover, individuals with IH and T2DM exhibited lower Matsuda, insulinogenic, and disposition indexes as compared to the iIFG group. CONCLUSIONS: 1-h PG-based criteria for diagnosis of IH and diabetes identify individuals having an unfavorable cardiometabolic risk profile with a progressive reduction in insulin sensitivity associated with impaired ß cell function.

Targeting PYK2 with heterobifunctional T6BP helps mitigate MASLD and MASH-HCC progression.

BACKGROUND & AIMS: The mechanisms underlying the regulation of hepatocyte non-receptor tyrosine kinases in metabolic dysfunction-associated steatohepatitis (MASH) remain largely unclear. METHODS: Hepatocyte-specific overexpression or deletion and anti-protein tyrosine kinase 2 beta (PYK2) or anti-TRAF6-binding protein (T6BP) crosslinking were utilised to study fatty liver protection by T6BP. P-PTC, a peptide-proteolysis targeting chimaera, degrades PYK2 to block MASH progression. RESULTS: Since PYK2 activation is promoter signalling in steatohepatitis development, we find that T6BP is a novel and critical suppressor of PYK2 that reduces hepatic lipid accumulation, pro-inflammatory factor release, and pro-fibrosis production by ubiquitin ligase CBL to degrade PYK2. Mechanistic evidence suggests that T6BP directly targets PYK2 and prevents its N-terminal FERM domain-triggered dimerization, disrupting downstream PYK2-JNK signalling hyperactivation. Additionally, T6BP favourably recruits CBL, a particular E3 ubiquitin ligase targeting PYK2, to form a complex and degrade PYK2. T6BP (F1), a core fragment of T6BP, directly blocks N-terminal FERM domain-associated dimerization of PYK2, followed by T6BP-recruiting CBL-mediated PYK2 degradation in a typical T6BP-dependent manner when the tiny fragment is specifically expressed using thyroxine binding globulin (TBG)-ground vectors. This inhibits the progression of MASH, metabolic dysfunction-associated steatotic liver disease (MASLD)-related HCC (MASH-HCC), and metabolic syndrome in dietary rodent models. First-ever peptide-proteolysis targeting chimaera (P-PTC) based on the core segment of T6BP as a ligand for targeted recruitment of CBL targeting metabolic disorders like MASH has been devised and validated in animal models. CONCLUSIONS: Our study revealed a previously unknown mechanism: identification of T6BP as a key eliminator of fatty liver strongly contributes to the development of promising therapeutic targets, and the discovery of crucial fragments of T6BP-based pharmacon that interrupt PYK2 dimerization are novel and viable treatments for fatty liver and its advanced symptoms and complications. IMPACT AND IMPLICATIONS: Excessive high-energy diet ingestion is critical in driving steatohepatitis via regulation of hepatocyte non-receptor tyrosine kinases. The mechanisms under lying the regulation of hepatocyte PYK2 in metabolic dysfunction-associated steatohepatitis (MASH) remain largely unclear. Here, we found that T6BP as a critical fatty liver eliminator has a significant impact on the development of promising therapeutic targets. Additionally, vital T6BP-based pharmacon fragments that impede PYK2 dimerization have been found, offering new and effective treatments for advanced fatty liver symptoms and complications.

Mangiferin prevents glucolipotoxicity-induced pancreatic beta-cell injury through modulation of autophagy via AMPK-mTOR signaling pathway.

The aim of this study was to investigate the protective effects of Mangiferin (MG) on glucolipotoxicity-induced pancreatic beta-cell injury. In vivo administration of MG significantly reduced the level of blood glucose in high-fat diet (HFD)-fed mice. MG treatment inhibited beta-cell apoptosis in HFD-treated mice. In vitro, MG protected INS-1 cells against apoptosis and impairment of insulin secretion following High glucose/Palmitic acid (HG/PA) treatment. MG treatment enhanced autophagy flux which was blocked by HG/PA treatment. Inhibition of autophagosome formation by 3-Methyladenine or blockade of autolysosome by Chloroquine reversed the protective effects of MG on INS-1 cells. MG treatment increased AMPK phosphorylation and reduced mTOR activation in INS-1 cells. Administration of the AMPK blocker abrogated MG-induced autophagy, and similar results were observed in INS-1 cells after cotreatment with MG and mTOR activator. In conclusion, MG ameliorated pancreatic beta-cell injury induced by glucolipotoxicity through modulation of autophagy via the AMPK-mTOR pathway.

Penicillin binding proteins-based immunoassay for the selective and quantitative determination of beta-lactam antibiotics.

An immunoassay method based on penicillin-binding protein (PBP) was developed for the quantitative determination of 10 kinds of beta-lactam antibiotics (BLAs). First, two kinds of PBPs, which are named PBP1a and PBP2x, were expressed and purified, and they were characterized by SDS-PAGE and western blotting analysis. Then, the binding activity of PBP1a and PBP2x to template BLAs, cefquinome (CEFQ) and ampicillin (AMP), was determined. The effect of the buffer solution system, e.g., pH, ion concentration, and organic solvent, on the immune interaction efficiency between PBPs and BLAs was also evaluated. In the end, the PBP-based immunoassay method was developed and validated for the detection of 10 kinds of BLAs. Under optimal conditions, PBPs exhibited high binding affinity to BLAs. In addition, this method showed a high sensitivity for the detection of 10 kinds of BLAs with the limits of detection from 0.21 to 9.12 ng/mL, which are much lower than their corresponding maximum residual limit of European Union (4-100 ng/mL). Moreover, the developed PBP-immunoassay was employed for BLA detection from milk samples, and satisfactory recoveries (68.9-101.3 %) were obtained.

Pre-admission Penicillin Allergy Evaluation Before Hematopoietic Stem Cell Transplantation Optimizes Febrile Neutropenia Treatment and Inpatient Resource Utilization: Pre-Admission Penicillin Allergy Testing Improves Febrile Neutropenia Treatment During HSCT.

BACKGROUND: Febrile neutropenia is a common complication of conditioning chemotherapy for hematopoietic stem cell transplant (HSCT), but a major barrier for optimal treatment of febrile neutropenia is historical penicillin allergies. Our group recently published a development of a clinical pipeline for delabeling penicillin allergies in adult patients planned to undergo hematopoietic stem cell transplant (HSCT). In this retrospective cohort study, we followed patients to evaluate their outcomes during inpatient admission for HSCT. OBJECTIVES: We hypothesized that, among patients planned for HSCT with a self-reported penicillin allergy, completing penicillin allergy testing (amoxicillin ingestion challenge with or without concomitant penicillin skin testing) prior to HSCT admission would be associated with differences in inpatient treatment for febrile neutropenia (including antibiotic selection and timing of antibiotic administration) and improved inpatient resource utilization (including nursing and inpatient physician consults). STUDY DESIGN: We identified patients with a self-reported penicillin allergy who answered a penicillin allergy questionnaire and were subsequently admitted to our institution for HSCT. We divided the cohort into 2 groups: patients whose penicillin allergy was evaluated prior to admission (EPTA) and patients whose penicillin allergy was not evaluated prior to admission (NEPTA). We then performed comparison between the 2 groups for general clinical outcomes of HSCT admission (duration of admission, need for ICU transfer, readmission rate, etc.), febrile neutropenia treatment, and inpatient resource utilization. Statistics were calculated using the non-parametric two-tailed Fisher exact test for categorical outcomes and the non-parametric two-tailed Mann-Whitney U test for numerical outcomes RESULTS: Within our cohort, 35 patients completed penicillin allergy testing prior to HSCT admission (EPTA) and 44 patients did not (NEPTA). Demographics were similar between these groups, and there was no significant difference in the rate of febrile neutropenia during HSCT admission (EPTA 64% vs NEPTA 66%, p=1.00). EPTA patients were significantly more likely to receive standard first-line antibiotics (cefepime or ceftazidime) for febrile neutropenia (EPTA 95% vs NEPTA 65%, p=0.015) and time between febrile neutropenia onset and antibiotic administration was shorter (EPTA mean 66 mins vs NEPTA mean 121 mins, p=0.0058). No patients in the EPTA group experienced an immediate hypersensitivity reaction (hives, anaphylaxis, etc.) or severe cutaneous adverse reaction (SCAR) during HSCT admission. EPTA patients were also significantly less likely to require 1:1 nursing for antibiotic test doses, challenges, and desensitizations (EPTA 0% vs NEPTA 49%, p<0.0001); less likely to require inpatient allergy consult (EPTA 0% vs NEPTA 12%, p=0.031); and less likely to require inpatient antimicrobial stewardship consult (EPTA 0% vs NEPTA 13%, p=0.013) during their HSCT admission. CONCLUSIONS: In summary, patients who completed penicillin allergy testing prior to HSCT admission were more likely to receive first-line antibiotics and received antibiotics more rapidly for treatment of febrile neutropenia. Furthermore, patients who completed penicillin allergy testing prior to HSCT admission were less likely to require 1:1 nursing, inpatient allergy consults, and inpatient antimicrobial stewardship consults during HSCT admission.

Glia maturation factor-γ regulates amyloid-ß42 phagocytosis through scavenger receptor AI in murine macrophages.

Dysfunctional phagocytic clearance of ß-amyloid (Aß) in microglia and peripheral macrophages/monocytes has been implicated in Alzheimer's disease (AD), but the mechanisms underlying this dysfunction are not yet well understood. In this study, we examined the role of glia maturation factor-γ (GMFG), an actin-disassembly protein that is highly expressed in immune cells, in macrophage Aß phagocytosis and in regulating scavenger receptor AI (SR-AI), a cell-surface receptor that has previously been implicated in Aß clearance. GMFG knockdown increased phagocytosis of Aß42 in BMDMs and RAW264.7 murine macrophages, while GMFG overexpression reduced Aß42 uptake in these cells. Blocking with anti-SR-AI antibodies inhibited Aß42 uptake in GMFG-knockdown cells, establishing a role for SR-AI in Aß42 phagocytosis. GMFG knockdown increased SR-AI protein expression under both basal conditions and in response to Aß42 treatment via both the transcriptional and post-transcriptional level in RAW264.7 macrophages. GMFG knockdown modulated Aß42-induced K48-linked and K63-polyubiquitination of SR-AI, the phosphorylation of SR-AI and JNK, suggesting that GMFG plays a role for intracellular signaling in the SR-AI-mediated uptake of Aß. Further, GMFG-knockdown cells displayed increased levels of the transcriptional factor MafB, and silencing of MafB in these cells reduced their SR-AI expression. Finally, GMFG was found to interact with the nuclear pore complex component RanBP2, and silencing of RanBP2 in GMFG-knockdown cells reduced their SR-AI expression. Collectively, these data support the role of GMFG as a novel regulator of SR-AI in macrophage Aß phagocytosis, and may provide insight into therapeutic approaches to potentially slow or prevent the progression of AD.

Zinc and methyl jasmonate improve sugar beet tolerance to high boron stress by enhanced leaf photochemical performance.

Nutrient imbalances, such as high boron (B) stress, occur within, as well as across, agricultural systems worldwide and have become an important abiotic factor that reduces soil fertility and inhibits plant growth. Sugar beet is a B-loving crop and is better suited to be grown in high B environments, but the methods and mechanisms regarding the enhancement of high-B stress tolerance traits are not clear. The main objective of this research was to elucidate the effects of the alone and/or combined foliar spraying of zinc sulfate (ZnSO4) and methyl jasmonate (MeJA) on the growth parameters, tolerance, and photochemical performance of sugar beet under high-B stress. Results demonstrated that the photosynthetic performance was inhibited under high-B stress, with a reduction of 11.33% in the net photosynthetic rate (Pn) and an increase of 25.30% in the tolerance index. The application of ZnSO4, MeJA, and their combination enhanced sugar beet's adaptability to high-B stress, with an increase in Pn of 9.22%, 4.49%, and 2.85%, respectively, whereas the tolerance index was elevated by 15.33%, 8.21%, and 5.19%, respectively. All three ameliorative treatments resulted in increased photochemical efficiency (Fv/Fm) and the photosynthetic performance index (PIABS) of PSII. Additionally, they enhanced the light energy absorption (ABS/RC) and trapping capacity (DIO/RC), reduced the thermal energy dissipation (TRO/RC), and facilitated the QA to QB transfer in the electron transport chain (ETC) of PSII, which collectively improved the photochemical performance. Therefore, spraying both ZnSO4 and MeJA can better alleviate high-B stress and promote the growth of sugar beet, but the combined spraying effect of ZnSO4 and MeJA is lower than that of individual spraying. This study provides a reference basis for enhancing the ability of sugar beet and other plants to tolerate high-B stress and for sugar beet cultivation in high B areas.

Whole genome sequence analysis of morphological changes in Haemophilus influenzae after beta-lactam exposure.

This report describes mutations in genes responsible for cell deformities in haemophili under pressure of beta-lactams in vitro. Light and transmission electron microscopy confirmed a hypothesis regarding changes in shape of haemophili that had become more filamentous in the presence of ampicillin (2mg/L) and cefuroxime (8mg/L) after 30 days of serial passage. The size of short axis increased by 28% (from 0.767µm to 1.06µm), the length of the long axis increased by 54% (from 1µm to 2.175µm). Along with that, whole genome sequencing analysis (Illumina platform, software PROKKA) revealed a variety of mutations in genes responsible for cell morphology in isolates examined in this study: ftsI (A1576 → C; G1154 → C; T986 → C; G1684 → C), mreB (C476 → T), mreC (A5 → G), mrdA (A1148 → G; C179 → T; G1613 → T), mrdB (T668 → G), mltC (C1016 → T), rodA (T668 → G). Results of this study indicate that shifting in bacterial shape could play a role in adaptation of haemophili to a new niche created by beta-lactams as a strategy of survival the antibiotic therapy.

Assessment of Serum Vitamin D and Parathyroid Hormone in Children With Beta Thalassemia Major: A Case-Control Study.

BACKGROUND: A defective synthesis of vitamin D contributes to alterations in calcium homeostasis due to chronic endocrinopathies, leading to metabolic bone diseases. This study aimed to ascertain the levels of calcium, vitamin D, and parathyroid hormone (PTH) in children with ß-thalassemia. METHODS: In this case-control study, 36 children with major ß-thalassemia receiving iron chelation therapy were included. For the control group, 36 cases matched for age and sex were selected. The packed cell volume (PCV) requirements varied among the thalassemic children, with an average PCV requirement of 78.57±49.07. The study was conducted for six months in the Department of Pediatrics at the Government Medical College, Nagpur, India. Serum PTH levels were determined by immunoassay, and serum vitamin D levels were assessed using electrochemiluminescence technique. Additional tests looked at liver function, serum ferritin, calcium, phosphorus, and complete blood count. The student's t-test, Mann-Whitney, and chi-square tests were used for statistical analysis. RESULT: In comparison to the control group (10.4±1.21 g/dL), the case group's mean hemoglobin level was considerably lower (5.62±1.9 g/dL) (p<0.001). The mean serum ferritin level in the cases was notably higher (3073±1262.24 ng/mL) compared to the control group's level (58.37±29.67 ng/mL) (p<0.001). A total of 80.6% of cases compared to 5.6% of controls had vitamin D deficiency, and 72.2% of cases compared to 2.8% of controls had PTH deficit, both of which showed statistically significant differences (p<0.001). Significant differences were observed between the case and control groups for the mean levels of total serum calcium (8.51±0.84 mg/dL), vitamin D (15.23±10.07 ng/mL), and PTH (14.66±19.86 pg/mL) (9.13±0.6 mg/dL, p=0.05; 34.94±9.57 ng/mL, p<0.001; 32.08±12.42 pg/mL, p<0.001; respectively). CONCLUSION: Growth failure may result from the markedly reduced serum calcium, vitamin D, and PTH levels in children with ß-thalassemia. The relevance of treatment approaches is highlighted by the possibility that these anomalies are caused by excessive iron and inadequate nutritional support.

Majeed syndrome: first description in a patient of central-European ancestry.

OBJECTIVES: We present the first case of a Majeed syndrome in a girl of central-European ancestry. METHODS: : Patient's medical records were reviewed. A NGS panel for autoinflammatory diseases was performed and the mutation was confirmed by Sanger analysis. Freshly isolated monocytes were activated with LPS +/- ATP. The concentration of inflammatory cytokines was assessed in monocytes supernatants. RESULTS: A 2-year-old girl presented with pain in the lower limbs, increase of acute phase reactants and persistent microcytic anaemia. The MRI showed bilateral STIR hyper-intensity of the spongy osseous tissue of femur, tibia, radius, ulna, and astragalus. Bone marrow analysis revealed increased trilinear cellularity with signs of dyserythropoietic anaemia. NGS panel detected the presence of two novel compound heterozygous mutations in the LPIN2 gene, confirmed by Sanger analysis. Treatment with anakinra was started with a prompt resolution of the clinical picture. Increased kinetics and concentration of IL-1ß was observed in the patient's monocytes compared with healthy controls, with a marked drop following the start of therapy. About six months after the start of the therapy, resolution of MRI findings, microcytic anaemia and dyserythropoiesis at bone marrow aspirate was observed. CONCLUSION: We describe the first case of Majeed syndrome in a patient of central-European ancestry. The functional test on circulating monocytes before and after therapy with anakinra confirmed pathogenicity of the mutation and the role of LPIN2 in the NLRP3 inflammasome activation. Anti-IL1 agents were effective, leading not only to the resolution of bone lesion but also to an improvement of dyserythropoiesis.

Chronic Oral Inoculation of Porphyromonas gingivalis and Treponema denticola Induce Different Brain Pathologies in a Mouse Model of Alzheimer Disease.

Periodontitis is a chronic inflammatory disease driven by dysbiosis in subgingival microbial communities leading to increased abundance of a limited number of pathobionts, including Porphyromonas gingivalis and Treponema denticola. Oral health, particularly periodontitis, is a modifiable risk factor for Alzheimer disease (AD) pathogenesis, with components of both these bacteria identified in postmortem brains of persons with AD. Repeated oral inoculation of mice with P. gingivalis results in brain infiltration of bacterial products, increased inflammation, and induction of AD-like biomarkers. P. gingivalis displays synergistic virulence with T. denticola during periodontitis. The aim of the current study was to determine the ability of P. gingivalis and T. denticola, grown in physiologically relevant conditions, individually and in combination, to induce AD-like pathology following chronic oral inoculation of female mice over 12 weeks. P. gingivalis alone significantly increased all 7 brain pathologies examined: neuronal damage, activation of astrocytes and microglia, expression of inflammatory cytokines interleukin 1ß (IL-1ß) and interleukin 6 and production of amyloid-ß plaques and hyperphosphorylated tau, in the hippocampus, cortex and midbrain, compared to control mice. T. denticola alone significantly increased neuronal damage, activation of astrocytes and microglia, and expression of IL-1ß, in the hippocampus, cortex and midbrain, compared to control mice. Coinoculation of P. gingivalis with T. denticola significantly increased activation of astrocytes and microglia in the hippocampus, cortex and midbrain, and increased production of hyperphosphorylated tau and IL-1ß in the hippocampus only. The host brain response elicited by oral coinoculation was less than that elicited by each bacterium, suggesting coinoculation was less pathogenic.

Negative Predictive Value of Single-Day Drug Provocation Test for Immediate and Non-Immediate Beta-Lactam Hypersensitivity Reactions in Children.

INTRODUCTION: Beta-lactam antibiotics (BLAs) commonly cause hypersensitivity reactions in children. These reactions are categorized into immediate reactions, which include urticaria, angioedema, bronchospasm, and anaphylaxis, and non-immediate reactions, such as maculopapular rashes and delayed-onset urticaria/angioedema. Rashes in children, often caused by infections, may be misdiagnosed as BLA allergy. However, over 90% tolerate the medication following an allergic evaluation. METHODS: We aimed to evaluate patients with negative single-day drug provocation test (sdDPT) results for subsequent reactions and to determine the negative predictive value (NPV) of sdDPT for immediate (less than 1 h) and non-immediate (more than 1 h) suspected BLA allergy. In addition, non-immediate reactions were assessed by classifying them as occurring within 1-6 h or after 6 h. Patients who underwent sdDPT for suspected BLA allergy and tested negative between 2019 and 2023 were included in the study. They were questioned via telephone interviews about their reuse of the tested drug. RESULTS: 404 patients who underwent sdDPT for suspected BLA allergy were evaluated. The NPV of BLA sdDPT was determined to be 97.3%. When patients were categorized based on the time interval between the last dose and the reaction, the NPV was 97% for those experiencing a reaction within the first hour of drug use and 96.7% for reactions occurring after more than 1 h. Non-immediate reactions were further evaluated, revealing an NPV of 98.7% for reactions occurring between 1 and 6 h, and 92.5% for reactions occurring after 6 h. CONCLUSION: Our findings demonstrate that sdDPT has a high NPV for both immediate and non-immediate reactions. However, the NPV of sdDPT was lower for reactions occurring more than 6 h after the last dose.

Congenital Long QT Syndrome Unmasked by Albuterol in an Adolescent with Asthma.

BACKGROUND: Patients with congenital long QT syndrome (LQTS) are prone to ventricular dysrhythmia but may be initially asymptomatic with a normal QTc interval on resting electrocardiogram (ECG). Albuterol is listed as a medication that poses a "special risk" to patients with congenital LQTS, but its effects have been rarely described. We present a case of previously unknown, asymptomatic congenital LQTS unmasked by albuterol in an adolescent with asthma. CASE REPORT: A 12-year-old girl with a history of asthma presented to the emergency department (ED) with shortness of breath, wheezing, and tachycardia for 24 h, consistent with acute asthma exacerbation. She received two doses of her home albuterol inhaler 2 h prior to presentation. Initial ECG demonstrated a QTc of 619 ms. Her remaining history, clinical examination, and laboratory workup, including electrolytes, were unremarkable. She was observed with cardiac monitoring before being discharged from the ED in stable condition for next-day outpatient pediatric cardiology follow-up. Resting office ECGs revealed QTcs from 440-470 ms. Exercise stress test revealed QTc prolongation of 520 ms and 500 ms at minute-2 and minute-4 of recovery, respectively. Genetic testing revealed heterozygous pathogenic variants in KCNQ1, consistent with type 1 LQTS. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Albuterol may be a cause of marked QTc prolongation in ED patients with underlying congenital LQTS, which can be a diagnostic clue in previously unidentified patients. Extreme QTc prolongation also serves as an indication in the ED for Cardiology consultation, laboratory evaluation for electrolyte imbalances, and observation with cardiac monitoring.

Characterization of acquired ß-lactamases in Pseudomonas aeruginosa and quantification of their contributions to resistance.

Pseudomonas aeruginosa is a highly problematic opportunistic pathogen that causes a range of different infections. Infections are commonly treated with ß-lactam antibiotics, including cephalosporins, monobactams, penicillins, and carbapenems, with carbapenems regarded as antibiotics of last resort. Isolates of P. aeruginosa can contain horizontally acquired bla genes encoding ß-lactamase enzymes, but the extent to which these contribute to ß-lactam resistance in this species has not been systematically quantified. The overall aim of this research was to address this knowledge gap by quantifying the frequency of ß-lactamase-encoding genes in P. aeruginosa and by determining the effects of ß-lactamases on susceptibility of P. aeruginosa to ß-lactams. Genome analysis showed that ß-lactamase-encoding genes are present in 3% of P. aeruginosa but are enriched in carbapenem-resistant isolates (35%). To determine the substrate antibiotics, 10 ß-lactamases were expressed from an integrative plasmid in the chromosome of P. aeruginosa reference strain PAO1. The ß-lactamases reduced susceptibility to a variety of clinically used antibiotics, including carbapenems (meropenem, imipenem), penicillins (ticarcillin, piperacillin), cephalosporins (ceftazidime, cefepime), and a monobactam (aztreonam). Different enzymes acted on different ß-lactams. ß-lactamases encoded by the genomes of P. aeruginosa clinical isolates had similar effects to the enzymes expressed in strain PAO1. Genome engineering was used to delete ß-lactamase-encoding genes from three carbapenem-resistant clinical isolates and increased susceptibility to substrate ß-lactams. Our findings demonstrate that acquired ß-lactamases play an important role in ß-lactam resistance in P. aeruginosa, identifying substrate antibiotics for a range of enzymes and quantifying their contributions to resistance.IMPORTANCEPseudomonas aeruginosa is an extremely problematic pathogen, with isolates that are resistant to the carbapenem class of ß-lactam antibiotics being in critical need of new therapies. Genes encoding ß-lactamase enzymes that degrade ß-lactam antibiotics can be present in P. aeruginosa, including carbapenem-resistant isolates. Here, we show that ß-lactamase genes are over-represented in carbapenem-resistant isolates, indicating their key role in resistance. We also show that different ß-lactamases alter susceptibility of P. aeruginosa to different ß-lactam antibiotics and quantify the effects of selected enzymes on ß-lactam susceptibility. This research significantly advances the understanding of the contributions of acquired ß-lactamases to antibiotic resistance, including carbapenem resistance, in P. aeruginosa and by implication in other species. It has potential to expedite development of methods that use whole genome sequencing of infecting bacteria to inform antibiotic treatment, allowing more effective use of antibiotics, and facilitate the development of new antibiotics.

Ketogenic diet with aerobic exercise can induce fat browning: potential roles of ß-hydroxybutyrate.

Introduction: Despite evidence suggesting that metabolic intermediates like ß-HB influence white adipose tissue (WAT) metabolism, the precise molecular mechanisms remain unclear. The aim of this study was to investigate the impact of beta-hydroxybutyrate (ß-HB) on the fat browning program and to explore the underlying molecular mechanisms using both in vitro and in vivo models. We assessed the effects of ß-HB on fat browning in adipocytes using 3T3-L1 cells and rat models. Methods: We evaluated the effects of ß-HB on fat browning, thermogenesis, lipid accumulation, adipokine expression, and mitochondrial biogenesis by treating mature 3T3-L1 adipocytes with sodium ß-HB for 24 h or by continuously exposing preadipocytes to ß-HB during the 8-day differentiation process. Male Sprague Dawley rats were divided into control, exercise only (EX), ketogenic diet only (KD), and combined exercise and ketogenic diet (KE) groups for an 8-week intervention involving diet and/or exercise. After intervention, we evaluated WAT histology, plasma lipids and adipokines, and the expression of markers related to fat browning, thermogenesis and mitochondrial biogenesis in WAT of rats. Results: In our adipocyte culture experiments, ß-HB reduced intracellular lipid accumulation by enhancing lipolysis and stimulated the expression of thermogenic and fat browning genes like uncoupling protein 1 (UCP1), PR domain containing 16 (PRDM16), and adipokines such as fibroblast growth factor 21 (FGF21) and Fibronectin type III domain-containing protein 5 (FDNC5). Additionally, ß-HB activated the AMPK-SIRT1-PGC-1α pathway, with UCP1 and PRDM16 upregulation mediated by ß-HB intracellular action and SIRT1 activity. In animal experiments, KE group raised ß-HB levels, decreasing body weight and blood lipids. KD with EX promoted WAT browning possibly via AMPK-SIRT1-PGC-1α, augmenting PRDM16, UCP1, FGF21, and FNDC5 expression. Conclusion: ß-HB induction via KD and/or EX shows potential in promoting WAT browning by activating mitochondrial biogenesis, lipolysis, and thermogenesis, suggesting that dietary and physical intervention inducing ß-HB may benefit metabolic health.