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1.
Asian J Neurosurg ; 19(1): 97-100, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38751400

RESUMEN

Cerebral cavernous malformation is an angiographically occult, well-circumscribed, benign hamartoma consisting of thin-walled sinusoidal vascular channels. Intracranial mucormycosis represents one of the most severe manifestations of mucor infection. We, hereby, report a case of cavernous malformation made rarer with concomitant mucormycosis. A 22-year-old female presented with left-sided facial seizures since age of 7 years and headache for the past 3 years. Magnetic resonance imaging brain revealed a right posterior frontal lobe cavernous malformation. Right frontal craniotomy with excision of cavernoma was done. Gross examination showed a solid cystic mass with multiple mulberry protrusions. Histopathological examination revealed features of cavernous malformation with evidence of mucormycosis. A final diagnosis of cavernous malformation with mucormycosis was rendered and microbiological studies were advised. To the best of our knowledge, this is the first case report of a cerebral cavernous malformation with mucormycosis in an immunocompetent patient without any risk factor.

3.
J Clin Neurosci ; 123: 130-136, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38574684

RESUMEN

BACKGROUND: Aphasia is a language disorder acquired secondary to brain damage. This study aims to evaluate clinical and radiological profile of patients with post stroke aphasia and factors affecting its recovery. METHODS: We conducted a prospective study of patients with first left Middle or Anterior Cerebral Artery infarct or Intracerebral Hemorrhage (ICH) with aphasia admitted within 14 days of stroke onset. Aphasia Quotient (AQ) was assessed at 2 weeks (AQ1) and 3 months (AQ2) using Western Aphasia Battery-Hindi version. Magnetic Resonance Imaging of brain with Diffusion Tensor Imaging (DTI) of bilateral Arcuate Fasciculus (AF) and Corticospinal Tract was done at admission, and stroke volume, Laterality Indices of Fractional Anisotropy (LI-FA), Mean Diffusivity (LI-MD), Radial Diffusivity (LI-RD), Axial Diffusivity (LI-AD) and Apparent Diffusion Coefficient (LI-ADC) were obtained. RESULTS: 36 patients [8 ICH and 28 Acute Ischemic Stroke (AIS)] were included. AQ1 and AQ2 were significantly higher in subcortical stroke than cortical. AQ2 and increase in AQ scores (including its subscores) were significantly higher in ICH than AIS. National Institutes of Health Stroke Scale score at admission and volume of stroke had significant negative correlation with AQ1 and AQ2. Laterality Index of Fractional Anisotropy of Arcuate Fasciculus [LI-FA (AF)] had significant positive correlation with AQ2 and naming score at 3 months. Laterality Index of Mean Diffusivity of Arcuate Fasciculus [LI-MD (AF)] had significant negative correlation with AQ1, AQ2 and all subcomponents of AQ2. Significant positive correlation was seen between improvements in Modified Rankin Scale score and AQ. CONCLUSION: The study shows that DTI can be used to predict severity of aphasia at follow up and recovery in language and motor functions occur in parallel.


Asunto(s)
Afasia , Imagen de Difusión Tensora , Accidente Cerebrovascular , Humanos , Masculino , Femenino , Persona de Mediana Edad , Afasia/etiología , Afasia/diagnóstico por imagen , Estudios Prospectivos , India , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Anciano , Estudios de Seguimiento , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Recuperación de la Función/fisiología
4.
Heliyon ; 10(7): e28557, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38596128

RESUMEN

Background: Post-stroke pain is common after a stroke and might be underreported. We describe Persistent Facial Pain (PFP) developed in post-stroke patients. Method: ology: This was a prospective hospital-based cohort study of stroke patients, and patients were followed up. Out of 415 stroke patients, 26 developed PFP. Result: Out of all PFP patients, six patients had an ischemic stroke, and 20 had a hemorrhagic stroke. 57.7% of patients had hypertension, while 34.6 patients had diabetes. The stroke location was left-sided in 12 patients and right-sided in 14 patients. 46.15% of patients responded to venlafaxine, 30.77% responded to amitriptyline, and 23.08% responded to pregabalin. Conclusion: Persistent facial pain is a pain syndrome that might be missed in patients post-stroke. It might be more common in hemorrhagic stroke patients than in ischemic stroke patients. It responds adequately to antidepressants. A high index of suspicion is required to diagnose and appropriately manage these patients.

5.
Neurol India ; 72(1): 148-150, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38443018

RESUMEN

ABSTRACT: Infection is an important trigger of myasthenic crisis (MC), and those infections manifest with pneumonia and muscle involvement may result in more frequent MC. We report two myasthenia gravis (MG) patients with H1N1 infection, and highlight the reasons for deterioration. Two patients with MG had H1N1 infection. The diagnosis of MG was confirmed by neostigmine, repetitive nerve stimulation, and anti-acetylcholine receptor antibody tests. H1N1 was confirmed by nucleic acid detection study, and myositis by creatinine kinase. The patient with pneumonia and myositis had MC needing mechanical ventilation for 10 days, and the other patient without myositis did not have MC. They were treated with oseltamivir 75 mg twice daily for 5 days, and the patients with MC received ceftriaxone intravenously. Both the patients were on prednisolone and azathioprine, and none received prior H1N1 vaccination. The lady with MC with myositis was discharged on day 27 in wheelchair bound state, and the other one patient without myositis or MC was discharged on 6th day with full recovery. These patients highlight the need for evaluation for myositis along with pneumonia in the MG patients with H1N1 infection. Vaccination in MG patients on immunosuppression may be useful.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Miastenia Gravis , Miositis , Neumonía , Humanos , Miastenia Gravis/complicaciones , Miositis/diagnóstico , Neostigmina
6.
Rev. Pesqui. Fisioter ; 14(1)mar., 2024. tab, ilus
Artículo en Inglés, Portugués | LILACS | ID: biblio-1555417

RESUMEN

INTRODUCTION: Shoulder pain after stroke, a complication with a prevalence of up to 16­84% usually occurs after 2­3 months and leads to patients withdrawing from rehabilitation programs, staying in the hospital longer, having less limb function and having a great negative impact on their quality of life. The aim of the present study was to determine the effect of PEMF and NMES in reducing shoulder pain in patients with stroke. MATERIAL AND METHODS: A prospective, randomized controlled trial included 51 patients with shoulder pain following stroke. The patients were randomly assigned to three groups (17 people in each group): Pulsed Electromagnetic Field (PEMF), Neuromuscular Electrical Stimulation (NMES) and Control group. The outcome measures were Visual Analogue Scale (VAS), Modified Ashworth Scale (MAS) and Fugl Meyer Assessment­Upper Extremity (FMA-UE), Active and Passive Range of Motion (AROM/PROM) assessed at the baseline, six weeks into the intervention, and one week into the follow-up. RESULTS: VAS score for pain showed a mean change of 1.60, 1.60 and 4.94 in PEMF, NMES, and control respectively after 20 sessions. It showed pain was significantly improved in all the groups (p<0.001), but the effectiveness of the PEMF and NMES groups was superior to the control group. CONCLUSION: The current literature showed that PEMF & NMES are effective in improving post-stroke shoulder pain, spasticity, range of motion and motor function and a novel method for stroke patients undergoing rehabilitation.


INTRODUÇÃO: Dor no ombro após acidente vascular cerebral com prevalência de 16­84% geralmente ocorre após 2­3 meses e pode resultar na suspensão de programas de reabilitação, internações hospitalares mais longas e redução da função dos membros, prejudicando qualidade de vida dos pacientes com AVC. O objetivo do presente estudo foi determinar o efeito da PEMF e da EENM na redução da dor no ombro em pacientes com acidente vascular cerebral. MATERIAL E MÉTODOS: Um estudo prospectivo, randomizado e controlado incluiu 51 pacientes com dor no ombro pós-AVC. Os pacientes foram divididos aleatoriamente em três grupos (17 pessoas em cada grupo): grupo Campo Eletromagnético Pulsado (PEMF), grupo Estimulação Elétrica Neuromuscular (EENM) e grupo Controle. As medidas de resultados foram na Escala Visual Analógica (VAS), Escala de Ashworth Modificada (MAS) e Avaliação de Fugl Meyer ­ Extremidade Superior (FMA-UE), Amplitude de Movimento (AROM/PROM) foram avaliadas no início do estudo, após seis semanas de tratamento, e após um acompanhamento semanal. RESULTADOS: A pontuação VAS para dor mostrada uma alteração média de 1,60, 1,60 e 4,94 na PEMF, EENM e Controle, respectivamente, após 20 sessões. Mostrou melhora significativa entre os três grupos (p<0,001), mas a eficácia do grupo PEMF e EENM foi superior ao grupo Controle. CONCLUSÃO: O presente estudo mostrou que PEMF e EENM são eficazes na melhora da dor no ombro pós-AVC, espasticidade, amplitude de movimento e função motora e um novo método para pacientes com AVC em reabilitação. Nossas descobertas indicam que a eficácia da EENM é claramente superior à do PEMF na manutenção da analgesia a longo prazo.


Asunto(s)
Accidente Cerebrovascular , Dolor de Hombro , Estimulación Eléctrica
7.
ACS Med Chem Lett ; 15(2): 221-229, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38352838

RESUMEN

Cannabidiol (CBD 1) is a nonpsychotic cannabinoid-based drug approved by the U.S. FDA for treating refractory epilepsy, namely, Lennox-Gastaut and Dravet syndrome. However, its low aqueous solubility and oral bioavailability are compensated by administering high doses, and there is an increased demand for conjugates with improved properties. In this direction, the present work is focused on synthesizing CBD-based prodrugs to address the issue of poor solubility and oral bioavailability. Several CBD-based prodrugs were synthesized and studied in a battery of assays: viz, release kinetic (ex vivo), solubility (in vitro), chemical stability (in vitro), plasma stability (ex vivo), pharmacokinetics (in vivo), and efficacy studies (in vivo). Among the synthesized prodrugs, the morpholinyl CBD-based prodrugs 3a and 3aa showed good release behavior, stability, better solubility, and a plasma profile. Moreover, prodrug candidate 3aa showed better therapeutic efficacy. The present study identifies CBD-based prodrugs with improved physiochemical properties and oral exposure.

8.
N Am Spine Soc J ; 17: 100302, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38322114

RESUMEN

Background: Lumbar spinal fusion surgery is a well-established treatment for various spinal disorders. However, one of its complications, pseudoarthrosis, poses a significant concern. This study aims to explore the incidence, time and predictive factors contributing to pseudoarthrosis in patients who have undergone lumbar fusion surgery over a 10-year period. Methods: Data for this research was sourced from the PearlDiver database where insurance claims of patients who underwent multilevel lumbar spinal fusion between 01/01/2010 and 10/31/2022 were examined for claims of pseudoarthrosis within the 10 years of their index procedure. A variety of demographic, comorbid, and surgical factors were assessed, including age, gender, Elixhauser Comorbidity Index (ECI), surgical approach, substance use disorders and history of spinal disorders. Statistical analyses, including chi-squared tests, multivariate analysis, and cox survival analysis were employed to determine significant associations. Results: Among the 76,337 patients included in this retrospective study, 2.70% were diagnosed with symptomatic lumbar pseudoarthrosis at an average of 7.38 years in a 10-year follow-up. Multivariate and Cox hazard analyses revealed that significant predictors of symptomatic pseudoarthrosis development following multilevel primary lumbar fusion include vitamin D deficiency, osteoarthritis, opioid and NSAID use, tobacco use, and a prior history of congenital spine disorders. Conclusions: In summary, this study revealed a 2.70% incidence of symptomatic lumbar pseudoarthrosis within 10 years of the index procedure. It highlighted several potential predictive factors, including comorbidities, surgical approaches, and substance use disorders, associated with the development of symptomatic pseudoarthrosis. Future research should focus on refining our understanding of these factors to improve patient outcomes and optimize healthcare resource allocation.

9.
N Am Spine Soc J ; 17: 100305, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38264153

RESUMEN

Background: Patients with long-term follow-up after cervical decompression and fusion have often been noted to have development of adjacent segment degeneration with a smaller subset of these patients progressing to adjacent segment disease (ASD), which results in the development of new symptomatic radiculopathy or myelopathy referable to a site either directly above or below a prior fused segment. The cause of ASD is multifactorial often involving natural age-related progression of spondylosis, accelerated progression following cervical decompression and fusion, operative technique, and patient-related factors. The effect of age at the time of index cervical decompression and fusion on the need for reoperation for ASD is not fully understood. This study aims to establish underlying risk factors for the development of symptomatic cervical ASD following cervical decompression and fusion requiring reoperation in patients of various age groups. Methods: A retrospective database review of patients aged 20 or greater with insurance claims of primary cervical decompression and fusion over the course of 11 years and 10 months (January 01, 2010-October 31, 2022) was conducted using an insurance claims database. The primary outcome was to evaluate the incidence of cervical ASD requiring reoperation amongst patients stratified by age at the time of their primary procedure. Secondary outcomes included an evaluation of various risk factors for ASD following cervical decompression and fusion including surgeon-controlled factors such as the number of levels fused and approach taken, patient cervical pathology including cervical disc disorder and cervical spondylosis, and underlying patient medical comorbidities including osteoporosis and vitamin D deficiency, and substance use. Results: A total of 60,292 patient records were analyzed, where the overall reoperation incidence for symptomatic ASD was 6.57%, peaking at 8.12% among those aged 30 to 39 and decreasing with age. Regression analysis revealed ages lower than 50 years as more predictive for the development of symptomatic ASD requiring reoperation. Multivariate regression analysis identified predictive factors for reoperation, including age, Elixhauser Comorbidity Index (ECI), multiple-level surgery, cervical spondylosis, cervical disc disorder, osteoporosis, and vitamin D deficiency. Notably, these factors had a variable impact across various age groups, as revealed by subgroup analysis. Conclusions: The incidence of reoperation secondary to symptomatic ASD is 6.57%, highest in those aged 30 to 39. The surgical approach had no significant impact on the need for reoperation, but multiple-level fusions posed a consistent risk in the development of symptomatic ASD requiring reoperation. Patient factors like degenerative disc disease, spondylosis, osteoporosis, and vitamin D deficiency were associated, urging further age-specific risk assessment and nonoperative intervention exploration.

11.
Nat Prod Res ; : 1-6, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37799113

RESUMEN

A rapid, precise, accurate, and cost-effective liquid chromatography-mass spectrometer method was developed by using a novel extraction technique for the simultaneous quantification of major oleane derivatives: arjunetin, arjungenin, arjunolic acid, and arjunic acid of Terminalia arjuna in infused edible oil. An innovative idea was implemented to extract the active phytoconstituents from the oil matrix based on the freezing point of oils and extraction solvent. The developed method was validated for all four active compounds in the linear working range of 0.47-1.72 µg/mL, 0.845-2.93 µg/mL, 1.73-5.95 µg/mL and 0.62-2.22 µg/mL with good correlations value (r2) more than 0.99 for arjunetin, arjungenin, arjunolic acid, and arjunetin, respectively. Furthermore, the HPTLC method was also developed for the quick identification of all four active markers along with other phytoconstituents infused in oil.

12.
Artículo en Inglés | MEDLINE | ID: mdl-37675205

RESUMEN

Background: Sacral (S1) pedicle screw misplacement in posterior percutaneous fixation (PPF) can be related to anatomical variability and a lack of reliable radiographic landmarks. This study highlights a reproducible anatomical landmark (the "V" sign) for the safe localization of the S1 pedicle entry point under fluoroscopy. Methods: Human cadavers (n = 14) were dissected for the anatomical description of the "V" landmark and its relationship with the entry point of the S1 pedicle screw. The "V" landmark was defined medially by the lateral border of the superior articulating process of S1 and laterally by the posterior projection of the sacral ala. The mean distance was measured between the bottom point of the "V" landmark and the anatomical entry point to the S1 pedicle (V-S1 entry point distance). A similar measurement was conducted on computed tomography (CT) scans of 135 patients who underwent PPF using the "V" sign as a landmark for S1 pedicle screw placement (270 screws). These were retrospectively evaluated for appropriateness of S1 screw entry points and for proper S1 screw alignment and breaches. Results: In the 14 cadavers, irrespective of the laterality and sex, the V-S1 entry point distance averaged 11.7 mm. On the medial-lateral axis, all entry points converged within 2 mm of a vertical line intersecting the base of the "V." Additionally, the CT scan analysis (135 patients, 270 screws) revealed an optimal entry point for 100% of the screws and a 3.3% (n = 9 screws) breach rate. Six of the 9 identified breaches were minor, and only 1 (0.4% of the 270 screws) warranted revision. Conclusions: The "V" sign serves as a reliable anatomical and radiographic landmark for identifying the S1 pedicle entry point under fluoroscopic guidance. This landmark can help surgeons overcome the radiographic ambiguity of the sacral anatomy and ultimately reduces the rate of S1 pedicle screw misplacement. Level of evidence: Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

13.
Asian Pac J Cancer Prev ; 24(9): 3187-3193, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37774071

RESUMEN

INTRODUCTION: With growing trends in tobacco consumption, it has been observed that the age of initiation is gradually decreasing. To combat the deep-rooted problem of the Society, we need to target the adolescents at the time of their first consumption of tobacco forms. Hence, this study was conducted to assess the pattern of smokeless tobacco use among school going adolescents in senior secondary schools with the assessment of the sociodemographic factors responsible for initiation of smokeless tobacco use by adolescents. METHODS: A cross-sectional survey of total sample of 714 students across 9-11 standards in 3 schools of Delhi was done using a self-administered questionnaire after obtaining approval from Institutional Ethics Committee and School Health Scheme, Delhi. RESULT: Consumption of tobacco was found to be 27.9% at a frequency of 6-9 days in a period of one month and a majority of 31 (39.2%) students initiated the use in the age group of 10-11 years. Among the different SLT products, pan masala combined with zarda with 56 (70.8%) users, was found to be the most commonly consumed SLT product. Grocery shops were preferred POS among the students as (67%) of students obtained the SLT product from this POS. 56 (70.8%) of the students wanted to quit the habit of SLT use whereas 49 (62%) students tried to quit the habit and 43 (54.4%) students sought help in order to quit the habit. DISCUSSION: Such alarming results in terms of low age of initiation in Delhi is an emerging health problem. Adequate cessation programmes and schemes must be developed and strict implementation of laws and policies to achieve a tobacco free youth is the need of hour.


Asunto(s)
Tabaco sin Humo , Adolescente , Humanos , Niño , Estudios Transversales , Uso de Tabaco/epidemiología , India/epidemiología , Instituciones Académicas
14.
Environ Sci Pollut Res Int ; 30(42): 95039-95053, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37580476

RESUMEN

More than 60% of India's population relies on agriculture as their primary source of income, making it the nation's most important economic sector. Rice husk (often abbreviated as RH) is one of the most typical by-products of agricultural production. Every five tonnes of rice that is harvested results in the production of one tonne of husk. The concept of recycling and reusing waste from agricultural production has received interest from a variety of environmental and industrial perspectives. A wide variety of nanomaterials, including nano-zeolite, nanocarbon, and nano-silica, have been discovered in agro-waste. From rice cultivation to the finished product, there was a by-product consisting of husk that comprised 20% of the overall weight, or RH. The percentage of silica in RH ash ranges from 60 to 40%, with the remaining percentage consisting of various minerals. As a direct consequence of this, several distinct approaches to generating and extracting nanomaterial from rice husk have been developed. Because it contains a significant amount of cellulose and lignin, RH is an excellent and economical source of carbon precursor. The goal of this chapter is to produce carbon-based nanomaterials from RH.


Asunto(s)
Nanoestructuras , Oryza , Carbono
15.
Cureus ; 15(7): e42037, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37593280

RESUMEN

Paroxysmal kinesigenic dyskinesia (PKD) is characterized by recurrent attacks of abnormal involuntary movements that are triggered by sudden movement, intention to move, or acceleration. A 10-year-old boy presented with paroxysmal, involuntary twisting movements of the left upper and lower limbs, precipitated by sudden body movements, lasting for 10-15 seconds and subsiding spontaneously. On examination, choreiform movements were observed, which were precipitated by sudden movements during some activities. The patient responded to carbamazepine with complete subsidence of the movements. The diagnosis of PKD was further confirmed by genetic testing. A high suspicion index helps in the prompt and early diagnosis of this rare entity.

16.
Clin J Pain ; 39(11): 604-610, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37584413

RESUMEN

OBJECTIVE: This study aimed to determine the effectiveness of pregabalin for the control of symptoms in mild to moderate idiopathic Carpal tunnel syndrome (CTS). METHODS: In this randomized, placebo-controlled trial, 146 mild to moderate idiopathic CTS patients were randomized into pregabalin (n=74) and placebo groups (n=72). Per protocol, analysis was conducted with 131 patients; pregabalin (n=65) and placebo (n=66). The drug titration dose was 50 mg once daily for the first week, twice daily for the second week and thrice daily for the next 6 weeks. The primary outcome included a change in the Symptom Severity Scale and Functional Status Scale (FSS) of the Boston Carpal Tunnel Questionnaire after the eighth week. The secondary outcome was the change in clinical and electrophysiological grading after 8 weeks of therapy. RESULTS: There was a statistically significant improvement in the mean Symptom Severity Scale (14.92±3.72 vs. 16.55±4.45; P =0.025) and FSS (10.77±2.64 vs. 12.0±2.55; P =0.007) in the pregabalin group after 8 weeks. Mean clinical and electrophysiological grading changed significantly from 2.3±0.7 to 2.1±0.8 ( P =0.001) and 1.9±0.7 to 1.8±0.8 ( P =0.020), respectively in the pregabalin group but not in the placebo group. DISCUSSION: The results of this study demonstrates that pregabalin is effective in ameliorating symptoms and improving functional outcomes in mild to moderate idiopathic CTS.


Asunto(s)
Síndrome del Túnel Carpiano , Humanos , Síndrome del Túnel Carpiano/tratamiento farmacológico , Síndrome del Túnel Carpiano/diagnóstico , Pregabalina/uso terapéutico , Estudios Prospectivos , Proyectos de Investigación , Resultado del Tratamiento
17.
Artículo en Inglés | MEDLINE | ID: mdl-37407860

RESUMEN

In this paper, the thermo-hydraulic performance of a solar air heater (SAH) duct roughened with discrete D-shaped ribs is numerically investigated using ANSYS Fluent 2020 R2. The numerical investigation is carried out at rib radius to transverse pitch ratio (r/Pt) from 0.1 to 0.35 and longitudinal pitch to rib radius ratio (Pl /r) from 4 to 10 under various operating conditions with Reynolds number (Re) varied from 10,200 to 20,200. The numerical results are validated with previous experimental results for the Nusselt number (Nu) values, and good agreement is found with mean absolute percentage error (MAPE) of 3.6%. Based on the results of the numerical investigation, it was found that the value of Nu and the friction factor (f) decreases with the increase of the value of Pl/r, while the ratio r/Pt is kept constant. From the overall analysis, it is concluded that the optimum results are obtained for r/Pt of 0.25 and Pl/r = 4, and the maximum thermo-hydraulic performance parameter is 1.12. Further correlations are developed for the value of Nu and f for the whole range of r/Pt as 0.10-0.35 and Pl/r as 4-10. According to the developed correlations, the values of Nu are within ± 2% of the results of CFD, while the values of f are within ± 2.7% of the results of CFD.

18.
J Phys Chem Lett ; 14(18): 4334-4341, 2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-37133894

RESUMEN

The mechanism of photochemical CO2 reduction to formate by PCN-136, a Zr-based metal-organic framework (MOF) that incorporates light-harvesting nanographene ligands, has been investigated using steady-state and time-resolved spectroscopy and density functional theory (DFT) calculations. The catalysis was found to proceed via a "photoreactive capture" mechanism, where Zr-based nodes serve to capture CO2 in the form of Zr-bicarbonates, while the nanographene ligands have a dual role of absorbing light and storing one-electron equivalents for catalysis. We also find that the process occurs via a "two-for-one" route, where a single photon initiates a cascade of electron/hydrogen atom transfers from the sacrificial donor to the CO2-bound MOF. The mechanistic findings obtained here illustrate several advantages of MOF-based architectures in molecular photocatalyst engineering and provide insights on ways to achieve high formate selectivity.

19.
Cureus ; 15(4): e37275, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37182082

RESUMEN

Thromboembolic complications after the COVID-19 vaccination have been reported from all over the world. We aimed to identify the thrombotic and thromboembolic complications that can arise after receiving various types of COVID-19 vaccines, their frequency, and distinguishing characteristics. Articles published in Medline/PubMed, Scopus, EMBASE, Google Scholar, EBSCO, Web of Science, the Cochrane Library, the CDC database, the WHO database, ClinicalTrials.gov, and servers like medRxiv.org and bioRxiv.org, as well as the websites of several reporting authorities between December 1, 2019, and July 29, 2021, were searched. Studies were included if they reported any thromboembolic complications post-COVID-19 vaccination and excluded editorials, systematic reviews, meta-analyses, narrative reviews, and commentaries. Two reviewers independently extracted the data and conducted the quality assessment. Thromboembolic events and associated hemorrhagic complications after various types of COVID-19 vaccines, their frequency, and distinguishing characteristics were assessed. The protocol was registered at PROSPERO (ID-CRD42021257862). There were 59 articles, enrolling 202 patients. We also studied data from two nationwide registries and surveillance. The mean age of presentation was 47 ± 15.5 (mean ± SD) years, and 71.1% of the reported cases were females. The majority of events were with the AstraZeneca vaccine and with the first dose. Of these, 74.8% were venous thromboembolic events, 12.7% were arterial thromboembolic events, and the rest were hemorrhagic complications. The most common reported event was cerebral venous sinus thrombosis (65.8%), followed by pulmonary embolism, splanchnic vein thrombosis, deep vein thrombosis, and ischemic and hemorrhagic stroke. The majority had thrombocytopenia, high D-dimer, and anti-PF4 antibodies. The case fatality rate was 26.5%. In our study, 26/59 of the papers were of fair quality. The data from two nationwide registries and surveillance revealed 6347 venous and arterial thromboembolic events post-COVID-19 vaccinations. COVID-19 vaccinations have been linked to thrombotic and thromboembolic complications. However, the benefits far outweigh the risks. Clinicians should be aware of these complications because they may be fatal and because prompt identification and treatment can prevent fatalities.

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