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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124947, 2025 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-39163769

RESUMEN

Plasmonic nanoparticles (NPs) hold considerable potential as photocatalysts owing to their robust light-matter interactions across diverse electromagnetic wavelengths, which significantly influence the photophysical characteristics of the adjacent molecular entities. Despite the widespread use of noble-metal NPs in surface-enhanced Raman scattering (SERS) applications, little is known about the kinetics of nanoparticle aggregation and how it affects their configurations. This study investigates the plasmon-driven photochemical conversion of 4-nitrobenzenethiol (NBT) to 4,4'-dimercaptoazobenzene (DMAB) on Au and Ag nanorods (NRs) through SERS. Significantly, photoconversion phenomena were observed on Ag NRs but not on Au NRs upon laser excitation at 633 nm. Finite-difference time-domain simulations revealed the presence of stronger electromagnetic fields on Ag NRs than on Au NRs. The aspect ratios and gaps between individual NPs in dimer configurations were determined to elucidate their effects on electromagnetic fields. The Ag NR dimer with an end-to-end configuration, an aspect ratio of 3.3, and a 1-nm gap exhibited the highest enhancement factor of 1.05 × 1012. Our results demonstrate that the primary contribution from diverse configurations in NR aggregates is the end-to-end configuration. The proposed NP design with adjustable parameters is expected to advance research in plasmonics, sensing, and wireless communications. These findings also contribute to the understanding of plasmon-driven photochemical processes in metallic nanostructures.

2.
Biomaterials ; 313: 122770, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39226653

RESUMEN

Major advances have been made in utilizing human-induced pluripotent stem cells (hiPSCs) for regenerative medicine. Nevertheless, the delivery and integration of hiPSCs into target tissues remain significant challenges, particularly in the context of retinal ganglion cell (RGC) restoration. In this study, we introduce a promising avenue for providing directional guidance to regenerated cells in the retina. First, we developed a technique for construction of gradient interfaces based on functionalized conductive polymers, which could be applied with various functionalized ehthylenedioxythiophene (EDOT) monomers. Using a tree-shaped channel encapsulated with a thin PDMS and a specially designed electrochemical chamber, gradient flow generation could be converted into a functionalized-PEDOT gradient film by cyclic voltammetry. The characteristics of the successfully fabricated gradient flow and surface were analyzed using fluorescent labels, time of flight secondary ion mass spectrometry (TOF-SIMS), and X-ray photoelectron spectroscopy (XPS). Remarkably, hiPSC-RGCs seeded on PEDOT exhibited improvements in neurite outgrowth, axon guidance and neuronal electrophysiology measurements. These results suggest that our novel gradient PEDOT may be used with hiPSC-based technologies as a potential biomedical engineering scaffold for functional restoration of RGCs in retinal degenerative diseases and optic neuropathies.


Asunto(s)
Células Madre Pluripotentes Inducidas , Polímeros , Células Ganglionares de la Retina , Humanos , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/citología , Células Madre Pluripotentes Inducidas/citología , Polímeros/química , Orientación del Axón , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Propiedades de Superficie , Conductividad Eléctrica , Factores de Crecimiento Nervioso/metabolismo , Axones/metabolismo , Axones/fisiología
3.
Arch Toxicol ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39249550

RESUMEN

The global burden of Inflammatory bowel disease (IBD) has been rising over the last decades. IBD is an intestinal disorder with a complex and largely unknown etiology. The disease is characterized by a chronically inflamed gastrointestinal tract, with intermittent phases of exacerbation and remission. This compromised intestinal barrier can contribute to, enhance, or even enable the toxicity of drugs, food-borne chemicals and particulate matter. This review discusses whether the rising prevalence of IBD in our society warrants the consideration of IBD patients as a specific population group in toxicological safety assessment. Various in vivo, ex vivo and in vitro models are discussed that can simulate hallmarks of IBD and may be used to study the effects of prevalent intestinal inflammation on the hazards of these various toxicants. In conclusion, risk assessments based on healthy individuals may not sufficiently cover IBD patient safety and it is suggested to consider this susceptible subgroup of the population in future toxicological assessments.

4.
J Orthop Case Rep ; 14(9): 111-115, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39253647

RESUMEN

Introduction: Metallosis which is traditionally associated with Metal-on-Metal (MoM) hip arthroplasty can occur with other bearing surfaces too, posing diagnostic challenges. They can be asymptomatic or present with local and systemic symptoms. This article reports a case of metallosis in a total hip replacement (THR) with metal on polyethylene (PE) articulation who presented with dislocation. It also reviews the pathology and various presentations of metallosis following hip arthroplasty. Case Report: A 35-year-old female patient presented 4 years after a left THR with recurrent dislocation. It was an uncemented prosthesis with metal on PE articulation. Serology and radiological investigations were done to evaluate for infection, implant loosening, implant malposition, etc. The femoral stem appeared to be in varus malposition. She was posted for revision surgery with a pre-operative plan to change the femoral stem and head if necessary. Intraoperative signs of local metallosis were noticed. Debridement was done along with the change of the femoral stem and bearing surface to ceramic on PE. Metallosis was also later confirmed by the histopathological report. The patient has been symptom-free during the 2-year follow-up period. Conclusion: Metallosis can occur even in non-MoM articulations and a high degree of clinical suspicion is required to detect the same preoperatively. Classical signs of metallosis can often be absent in the early disease and subtle signs of instability must be looked out for even in the absence of obvious misalignment in radiographic assessment. Metallosis when combined with malposition or malalignment can be more detrimental. If detected early before osteolysis and periarticular soft tissue damage sets in, a complete revision of all the implant components and abductor damage can be avoided. In suspected cases, a lower threshold should be adopted for sending blood and joint aspirates for cobalt-chromium levels.

5.
ACS Nano ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261016

RESUMEN

Heteroatom immobilization engineering (HAIE) is becoming a forefront approach in materials science and engineering, focusing on the precise control and manipulation of atomic-level interactions within heterogeneous systems. HAIE has emerged as an efficient strategy to fabricate single-atom sites for enhancing the performance of metal-based batteries. Despite the significant progress achieved through HAIE in metal anodes for metal-based batteries, several critical challenges such as metal dendrites, side reactions, and sluggish reaction kinetics are still present. In this review, we delve into the fundamental principles underlying heteroatom immobilization engineering in metal anodes, aiming to elucidate its role in enhancing the electrochemical performance in batteries. We systematically investigate how HAIE facilitates uniform nucleation of metal in anodes, how HAIE inhibits side reactions at the metal anode-electrolyte interface, and the role of HAIE in promoting the desolvation of metal ions and accelerating reaction kinetics within metal-based batteries. Finally, we discuss various strategies for implementing HAIE in electrode materials, such as high-temperature pyrolysis, vacancy reduction, and molten-salt etching and anchoring. These strategies include selecting appropriate heteroatoms, optimizing immobilization methods, and constructing material architectures. They can be utilized to further refine the performance to enhance the capabilities of HAIE and facilitate its widespread application in next-generation metal-based battery technologies.

6.
Artículo en Inglés | MEDLINE | ID: mdl-39261147

RESUMEN

INTRODUCTION: Alloimmunization and transfusion reactions underscore the crucial role of precise immunohematological techniques to enhance safety in transfusion. This study aims to determine the frequency of alloimmunization in patients treated at a Brazilian university hospital, investigate demographic, clinical, and epidemiological characteristics of patients with positive irregular antibody screening, as well as to assess the frequency of erythrocyte antigens and anti-erythrocyte antibodies in the population. MATERIALS AND METHODS: This retrospective observational study included all irregular antibody-positive patients treated at the transfusion service of Hospital de Clínicas of the Federal University of Uberlandia between January 2019 and December 2020. RESULTS: Of the 201 irregular antibody-positive patients, alloimmunization was more common in women (64.2%) than in men (35.8%). Blood groups A (39.8%) and O (38.8%), and Rh positive samples (69.1%) predominated, and about half (48.2%) of the patients were transfused for preoperative procedures. The most frequently found clinically significant alloantibodies were anti-D (27.2%), anti-E (15.0%), and anti-Kell (11.5%). Of the patients, 30.6% had multiple antibody associations, with anti-D and anti-C being the most common combination. Erythrocyte immunophenotyping was performed for 76 patients with the most frequent antigens detected being e (100%), c (86.8%), and C (40.8%). Among the 14 pregnant women evaluated, most were multiparous, 85.7% had anti-D as the most prevalent antibody, and had the A-negative blood type (33.3%). CONCLUSION: Alloantibody screening and identification associated with erythrocyte immunophenotyping are necessary for a better understanding of the alloimmunized population, ensuring greater safety and efficacy of transfusion therapy in the hospital setting.

7.
Artículo en Inglés | MEDLINE | ID: mdl-39261207

RESUMEN

OBJECTIVES: To retrospectively assess the incidence and severity of perioperative protamine reactions in adult patients with documented history of fish allergy. DESIGN: Retrospective observational study. SETTING: Large academic tertiary referral center. PARTICIPANTS: Adults with fish allergies undergoing surgeries involving protamine, between January 1, 2008, and March 1, 2018. INTERVENTIONS: Perioperative protamine administration in patients with documented fish allergy. MEASUREMENTS AND MAIN RESULTS: Perioperative protamine and anaphylactic reactions were reviewed. A diagnosis of anaphylaxis or protamine reaction was based on clinical suspicion, perioperative events, and postoperative evaluations. Among 214 patients, 2 cases (<1%) of anaphylaxis or protamine reactions occurred. Cardiac procedures were most common (67%). The median intraoperative heparin dosage was 46,000 IU, and the median protamine dosage was 310 mg. Nearly all patients (99%) were admitted to the intensive care unit postoperatively, with a median hospital stay of 6.5 days (interquartile range, 5.2-14.6 days). There were 3 deaths (1%) within 30 days, and 15 (7%) within 1 year. CONCLUSIONS: The study findings suggest that in patients with a history of fish allergy, cross-reactivity with protamine is unlikely, as anaphylaxis and/or protamine reactions were rare in this patient population in the perioperative environment. Based on these findings, this study does not recommend avoiding protamine solely based on a history of fish allergy when heparin reversal is required during surgery.

8.
Chembiochem ; : e202400450, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39255447

RESUMEN

Proteins are biological macromolecules well known to regulate many cellular signaling mechanisms. For instance, they are very appealing for their application as therapeutic agents, presenting high specificity and activity. Nonetheless, they suffer from unfolding, instability and low bioavailability making their administration through systemic and other routes very tough. To overcome these drawbacks, drug delivery systems and nanotechnology have arisen to deliver biomolecules in a sustained manner while, at the same time, increasing dose availability, protecting the cargo without compromising proteins' bioactivity, and enhancing intracellular delivery. In this work, we proposed the optimization of sphingomyelin nanosystems (SNs) for the delivery of a wide collection of proteins (ranging from 10-500 kDa and pI) using diverse chemical association strategies. We have further characterized SNs by varied analytical methodologies. We have also carried out in vitro experiments to validate the potential of the developed formulations. As the final goal, we aim to obtain evidence of the potential use of SNs for the development of protein therapeutics.

9.
BMJ Case Rep ; 17(9)2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39256179

RESUMEN

In this case, a woman in her 80s presented to the emergency department with signs and symptoms of acute pancreatitis that began after starting a course of doxycycline. Common aetiologies of acute pancreatitis, including alcohol use, gallstones and hypertriglyceridaemia were ruled out. Less common aetiologies, including recent Endoscopic Retrograde Cholangiopancreatography (ERCP) procedure, hypercalcaemia, malignancy, infection and trauma, were also ruled out, making drug-induced acute pancreatitis the most likely aetiology. After consideration of her medication list, doxycycline was determined to be the offending medication. On discontinuation and treatment with fluids and analgesics, her condition slowly improved.This case illustrates a rare but severe complication of doxycycline use. Determining the aetiology of drug-induced acute pancreatitis is more difficult in older patients due to high rates of polypharmacy. Recognition of doxycycline as an aetiology of drug-induced pancreatitis may allow earlier recognition and intervention in cases of suspected pancreatitis without a clear common aetiology in older patients with polypharmacy.


Asunto(s)
Antibacterianos , Doxiciclina , Pancreatitis , Humanos , Doxiciclina/efectos adversos , Doxiciclina/uso terapéutico , Femenino , Pancreatitis/inducido químicamente , Antibacterianos/efectos adversos , Anciano de 80 o más Años , Enfermedad Aguda
10.
Artículo en Inglés | MEDLINE | ID: mdl-39257138

RESUMEN

AIM: The objective of this Multicentric Post-Marketing Surveillance (PMS) study was to evaluate the safety and tolerance of vitamin C and zinc tablets in the Indian population experiencing deficiencies of these nutrients. Furthermore, the study aimed to provide insights into physicians' prescription practices and characterise the patient population receiving the study medication. METHODS: This prospective observational study involved 358 participants from 8 study sites across India (including 2 government hospital sites), spanning a duration of approximately 12 weeks (3 months). The primary aim was to evaluate the safety and tolerability of zinc and ascorbic acid effervescent tablets for those who were deficient in zinc and vitamin C. Throughout the study period, adverse events were monitored and categorised by MedDRA Primary System Organ Class and Preferred Term. The analysis included evaluating the incidence, percentage, and correlation of adverse events with the treatment (safety population). Additionally, the frequencies of adverse drug reactions were examined across all enrolled patients. Vital signs and symptom-focused physical examinations were conducted during each visit in the safety population. RESULTS: Out of 358 (100%) patients, only 12 (3.35%) experienced minor symptoms in the study period. The majority of patients reported gastrointestinal disorders, i.e., two (0.6%) patients reported constipation and gastritis, respectively. Diarrhoea was reported by four (1.1%) patients. One (0.3%) patient reported gastrointestinal pain. Three (0.8%) patients reported vomiting. Diarrhoea was the most common symptom reported. All patients possess a mild intensity of adverse drug reactions in safety populations. The P-value is less than 0.05 (p-value < 0.05), and therefore there is a statistically significant relationship between the predictor variables and the response variable (i.e., the expected count of adverse drug reactions). CONCLUSION: The fixed-dose combination of vitamin C and zinc effervescent tablets appears to be safe and tolerable for the treatment of vitamin C and zinc deficiencies in Indian patients. The favorable outcome underscores the mild nature of the adverse reactions and the right medical interventions and support.

.

11.
Thorac Cancer ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39257160

RESUMEN

BACKGROUND: Screening for anaplastic lymphoma kinase (ALK) rearranged non-small cell lung cancer (NSCLC) is crucial for identifying patients eligible for targeted therapy. The FDA-approved ALK (D5F3) immunohistochemistry (IHC) assay, used with the OptiView Amplification Kit, demonstrates excellent sensitivity and specificity in detecting these patients. However, the clinical significance of resulting focal positivity remains unclear, and ALK (D5F3) expression unrelated to ALK fusion is observed in some cases of neuroendocrine differentiation. This study aims to validate these findings with molecular testing and contribute to the accurate interpretation of ALK (D5F3) IHC results. METHODS: A total of 1619 patients diagnosed with NSCLC and neuroendocrine carcinoma were evaluated using ALK (D5F3) IHC. For cases with strong but focal expression and those with diffuse strong positivity in neuroendocrine differentiation, ALK fluorescence in situ hybridization (FISH) and/or next-generation sequencing (NGS) tests were performed. RESULTS: Seven out of 1109 adenocarcinomas (0.6%) and six out of 289 squamous cell carcinomas (2.1%) exhibited strong focal ALK (D5F3) expression. Nine out of 209 neuroendocrine carcinomas (4.3%) showed homogeneously strong ALK (D5F3) expression. All these cases, including adenocarcinoma with neuroendocrine differentiation and combined small cell carcinoma, were negative for ALK fusions by FISH and/or NGS. CONCLUSION: This study demonstrates that strong but focal ALK (D5F3) immunostaining and strong expression in neuroendocrine differentiation may not indicate ALK fusion. By considering these findings, we can improve the accuracy of patient selection for targeted therapy by minimizing false-positive interpretations of ALK (D5F3) staining.

12.
Immunol Invest ; : 1-22, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39258651

RESUMEN

INTRODUCTION: Anaphylaxis is a globally increasing allergic reaction that is often fatal. Recently, our previous study reported the possibility of using the modified natural products "sodium R-lipoate (NaRLA) and enzymatically modified isoquercitrin (EMIQ)" as potential novel safe agents against the non-immunological-degranulation of mast cells. METHODS: Here, we extended our previous findings by determining the antianaphylactic activity of 50 and 100 mg/kg body weight of NaRLA and EMIQ (given orally and prior to local or systemic challenge) in mice models of ovalbumin (OVA)-induced IgE-dependent active cutaneous anaphylaxis (ACA) and active systemic anaphylaxis (ASA) in comparison with sulfasalazine (SSZ, amast cell stabilizer). RESULTS: The pre-treatment of mice with NaRLA or EMIQ completely succeeded, as SSZ, in suppression of the increased vascular permeability associated with IgE-dependent ACA and protected the OVA-sensitized mice from fatal ASA by reducing (p < .001) the skin mast cell degranulation, the elevated peritoneal histamine and interleukin-4 levels, along with decreasing the associated sever gastrointestinal and lung histopathological alterations and inflammation. The high dose of EMIQ prevented death in 70% of mice with anaphylactic shock, better than SSZ. DISCUSSION: Our data indicated that NaRLA and EMIQ may be potential prophylactic and therapeutic candidates for the alleviation of atopic and systemic anaphylaxis.

13.
Int J Dermatol ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39258760

RESUMEN

Leprosy remains a significant neglected tropical disease despite the goal of elimination having been achieved in various endemic nations over the past two decades. Reactional episodes complicate the disease course, resulting in deformities and disability. The main aim of treatment is to kill Mycobacterium leprae and decrease the bacterial load, which could help prevent further bacilli transmission. A major concern in breaking the chain of transmission and possibly for recurrent reactions is the role of drug-resistant bacilli. Though some data is available on the background prevalence of drug resistance in leprosy, there is a paucity of studies that look for resistance specifically in leprosy reactions. Administration of long-term steroids or immunosuppressants for chronic and recurrent responses in the presence of drug resistance has the twin effect of perpetuating the multiplication of resistant bacilli and encouraging the dissemination of leprosy. The increasing trend of prescribing second-line drugs for leprosy or type 2 reactions without prior assessment of drug resistance can potentially precipitate a severe public health problem as this can promote the development of resistance to second-line drugs as well. A comprehensive multicenter study, including drug resistance surveillance testing in cases of reactions, is necessary, along with the current measures to stop the spread of leprosy. Here, we have detailed the history of drug resistance in leprosy, given pointers on when to suspect drug resistance, described the role of resistance in reactions, methods of resistance testing, and the management of resistant cases with second-line therapy.

14.
Chemistry ; : e202403051, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39259036

RESUMEN

Manganese catalysts that activate hydrogen peroxide have seen increased use in organic transformations, such as olefin epoxidation and alkane C-H bond oxidation. Proposed mechanisms for these catalysts involve the formation and activation of MnIII-hydroperoxo intermediates. Examples of well-defined MnIII-hydroperoxo complexes are rare, and the properties of these species are often inferred from MnIIIalkylperoxo analogues. In this study, we show that the reaction of the MnIII-hydroxo complex [MnIII(OH)(6Medpaq)]+ (1) with hydrogen peroxide and acid results in the formation of a dark-green MnIII-hydroperoxo species [MnIII(OOH)(6Medpaq)]+ (2). The formulation of 2 is based on electronic absorption, 1H NMR, IR, and ESI-MS data. The thermal decay of 2 follows a first order process, and variable-temperature kinetic studies of the decay of 2 yielded activation parameters that could be compared with those of a MnIII-alkylperoxo analogue. Complex 2 reacts with the hydrogen-atom donor TEMPOH two-fold faster than the MnIII-hydroxo complex 1. Complex 2 also oxidizes PPh3, and this MnIII-hydroperoxo species is 600-fold more reactive with this substrate than its MnIII-alkylperoxo analogue [MnIII(OOtBu)(6Medpaq)]+. DFT and time-dependent (TD) DFT computations are used to compare the electronic structure of 2 with similar MnIII-hydroperoxo and MnIII-alkylperoxo complexes.

15.
Artículo en Inglés | MEDLINE | ID: mdl-39265065

RESUMEN

Cascade-enzyme reaction systems have emerged as promising tools for treating malignant tumors by efficiently converting nutrients into toxic substances. However, the challenges of poor localized retention capacity and utilization of highly active enzymes often result in extratumoral toxicity and reduced therapeutic efficacy. In this study, we introduced a cell membrane-DNA nanoanchor (DNANA) with a spatially confined cascade enzyme for in vivo tumor therapy. The DNANAs are constructed using a polyvalent cholesterol-labeled DNA triangular prism, ensuring high stability in cell membrane attachment. Glucose oxidase (GOx) and horseradish peroxidase (HRP), both modified with streptavidin, are precisely confined to biotin-labeled DNANAs. Upon intratumoral injection, DNANA enzymes efficiently colonize the tumor site through cellular membrane engineering strategies, significantly reducing off-target enzyme leakage and the associated risks of extratumoral toxicity. Furthermore, DNANA enzymes demonstrated effective cancer therapy in vitro and in vivo by depleting glucose and producing highly cytotoxic hydroxyl radicals in the vicinity of tumor cells. This membrane-engineered cascade-enzyme reaction system presents a conceptual approach to tumor treatment.

16.
Cureus ; 16(8): e65945, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39221287

RESUMEN

Trimethoprim-sulfamethoxazole (TMP-SMX), a widely used antibiotic, is associated with both predictable dose-dependent side effects and rare, idiosyncratic adverse reactions. Here, we report the case of a previously healthy, non-G6PD-deficient, 27-year-old male who developed three idiosyncratic reactions: severe thrombocytopenia, aseptic meningitis, and hepatitis concurrently following TMP-SMX administration. The Naranjo adverse reaction probability score was 7, implying TMP-SMX as the probable cause of the clinical presentation. After a comprehensive workup to rule out alternate etiologies, we have established TMP-SMX as the culprit. Our case highlights the importance of early recognition of TMP-SMX-induced rare adverse events for appropriate management to mitigate long-term sequelae and ensure favorable patient outcomes.

17.
Integr Zool ; 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39218997

RESUMEN

Pavlovian fear conditioning serves as a valuable method for investigating species-specific defensive reactions (SSDRs) such as freezing and flight responses. The present study examines the role of white noise under different experimental conditions. Given that white noise has been shown to elicit both conditional (associative) and unconditional (nonassociative) defensive responses, we compared the response to noise following three separate training conditions: shock-only, white noise paired with shock, and context-only. Results showed that baseline freezing level significantly changed across groups: Both the shock-only group and the white noise paired with shock group froze more than the context-only group on the test day. White noise evoked differential freezing between groups on day 2: The shock-only group froze more than the context-only group although both groups were never exposed to white noise during training. Further, an activity burst triggered by white noise was similar for the shock-only and white noise paired with shock groups during testing, although shock-only group was never exposed to white noise stimuli during training. This aligned with c-fos data, indicating similar c-fos activity levels across different periaqueductal gray (PAG) regions for both shock-only and white noise paired with shock groups. However, the driving force behind c-fos activation-whether freezing, activity burst, or a combination of both-remains uncertain, warranting further analysis to explore specific correlations between SSDRs and c-fos activity within the PAG and related brain areas.

18.
J Comput Chem ; 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39221711

RESUMEN

The statistical quantum model (SQM), which assumes that the reactivity is controlled by entrance/exit channel quantum capture probabilities, is well suited for chemical reactions with a long-lived intermediate complex. In this work, a time-independent coupled-channel implementation of the SQM approach is developed for atom-triatom systems in full dimensionality. As SQM treats the capture dynamics quantum mechanically, it is capable of handling quantum effects such as tunneling. A detailed study of the H/D + O3 capture dynamics was performed by applying the newly developed SQM method on an accurate global potential energy surface. Agreement with previous ring polymer molecular dynamics (RPMD) results on the same potential energy surface is excellent except for very low temperatures. The SQM results are also in reasonably good agreement with available experimental rate coefficients. The strong H/D kinetic isotope effect underscores the dominant role of quantum tunneling under an entrance channel barrier at low temperatures.

19.
BMC Endocr Disord ; 24(1): 172, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39218880

RESUMEN

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare but life-threatening skin lesion triggered by hypersensitive drug reaction. They are characterized by extensive epidermal necrosis and skin exfoliation. Fulminant type 1 diabetes mellitus (FT1DM) is featured by a rapid-onset of hyperglycemia with ketoacidosis due to severely destroyed ß-cell function. Fulminant type 1 diabetes mellitus as a sequela of SJS/TEN has rarely been reported. CASE PRESENTATION: We present a 73-year-old female patient who developed SJS/TEN skin allergic reaction after taking carbamazepine and phenytoin for 35 days. Then, hyperglycemia and diabetic ketoacidosis occurred 20 days after discontinuation of antiepileptic drugs. A very low serum C-peptide level (8.79 pmol/l) and a near-normal glycosylated hemoglobin level met the diagnostic criteria for fulminant T1DM. Intravenous immunoglobulin (IVIG) and insulin were promptly administered, and the patient recovered finally. CONCLUSIONS: This rare case indicates that monitoring blood glucose is necessary in SJS/TEN drug reaction, and comprehensive therapy with rehydration, insulin, antibiotics, and IVIG may improve the prognosis.


Asunto(s)
Anticonvulsivantes , Diabetes Mellitus Tipo 1 , Síndrome de Stevens-Johnson , Humanos , Síndrome de Stevens-Johnson/etiología , Síndrome de Stevens-Johnson/complicaciones , Síndrome de Stevens-Johnson/diagnóstico , Femenino , Anciano , Diabetes Mellitus Tipo 1/complicaciones , Anticonvulsivantes/efectos adversos , Pronóstico , Carbamazepina/efectos adversos
20.
Front Physiol ; 15: 1427094, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39224206

RESUMEN

Introduction: Electrostatic binding of deoxyhemoglobin (Hb) to cytoplasmic domain of band 3 anion transport protein occurs as part of the glycolytic regulation in red blood cells (RBCs). Hb oxidation intermediates not only impact RBC's oxygenation but also RBC's membrane through the interaction with band 3. It is not known however whether these critical pathways undergo changes during the storage of RBCs. Methods and Results: Oxygen parameters of fresh blood showed a sigmoidal and cooperative oxygen dissociation curve (ODC) for the first week of storage. This was followed by a large drop in oxygen affinity (P50) (from 30 to 20 mmHg) which remained nearly unchanged with a slight elevation in Bohr coefficients and a significant drop in extracellular acidification rates (ECAR) at the 42-day storage. Oxidation of Hb increased with time as well as the formation of a highly reactive ferryl Hb under oxidative stress conditions. Ferryl Hb interacted avidly with RBC's membrane's band 3, but to lesser extent with old ghost RBCs. Discussion: The observed alterations in RBC's oxygen binding may have been affected by the alterations in band 3's integrity which are largely driven by the internal iron oxidation of Hb. Restoring oxygen homeostasis in stored blood may require therapeutic interventions that target changes in Hb oxidation and membrane changes.

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