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1.
Artículo en Inglés | MEDLINE | ID: mdl-39052020

RESUMEN

Laser-induced graphene (LIG) has been emerging as a promising electrode material for supercapacitors due to its cost-effective and straightforward fabrication approach. However, LIG-based supercapacitors still face challenges with limited capacitance and stability. To overcome these limitations, in this work, we present a novel, cost-effective, and facile fabrication approach by integrating LIG materials with candle-soot nanoparticles. The composite electrode is fabricated by laser irradiation on a Kapton sheet to generate LIG material, followed by spray-coating with candle-soot nanoparticles and annealing. Materials characterization reveals that the annealing process enables a robust connection between the nanoparticles and the LIG materials and enhances nanoparticle graphitization. The prepared supercapacitor yields a maximum specific capacitance of 15.1 mF/cm2 at 0.1 mA/cm2, with a maximum energy density of 2.1 µWh/cm2 and a power density of 50 µW/cm2. Notably, the synergistic activity of candle soot and LIG surpasses the performances of previously reported LIG-based supercapacitors. Furthermore, the cyclic stability of the device demonstrates excellent capacitance retention of 80% and Coulombic efficiency of 100% over 10000 cycles.

2.
Reproduction ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39056485

RESUMEN

Platelet-activating factor (PAF) has been implicated in a number of reproductive processes ranging from ovulation to embryo motility, but has not been widely explored in the mare. To identify the presence and examine the role of PAF in the equine periconception processes, targeted mass spectrometry coupled with chromatographic separation (LC-MS/MS) was performed on equine follicular fluid (FF), and PAF was quantitatively detected. Subsequently, untargeted high-resolution mass spectrometry-based lipidomic analysis was carried out to quantify PAF in different sized pre-ovulatory follicles, whereby different molecular species of PAF, PAF(14:0) and PAF(16:1), were both seen to be increasing with follicle diameter. These findings suggest that PAF within FF is increasing as preovulatory follicles approach ovulation. Additionally, immunofluorescence staining identified the PAF Receptor (PAFR) in the luminal pericellular, apical and basal aspect of equine oviductal epithelial cells. Lastly, an equine oviductal epithelial organoid model was generated, and showed that the addition of PAF significantly increased the ciliary beat frequency (CBF) (Hz), an action consistent with a role for PAF in embryo migration. It is proposed that the local action of PAF on the ciliated cells of the oviduct propels both the oocyte and the conceptus towards the uterus. In the mare, it appears that PAF is a contributor during the periconception period, potentially being a mediator in the mechanisms of ovulation and in the dialogue of very early pregnancy.

3.
Cells ; 13(8)2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38667331

RESUMEN

Gynecological and obstetric infectious diseases are crucial to women's health. There is growing evidence that links the presence of Fusobacterium nucleatum (F. nucleatum), an anaerobic oral commensal and potential periodontal pathogen, to the development and progression of various human diseases, including cancers. While the role of this opportunistic oral pathogen has been extensively studied in colorectal cancer in recent years, research on its epidemiological evidence and mechanistic link to gynecological diseases (GDs) is still ongoing. Thus, the present review, which is the first of its kind, aims to undertake a comprehensive and critical reappraisal of F. nucleatum, including the genetics and mechanistic role in promoting adverse pregnancy outcomes (APOs) and various GDs, including cancers. Additionally, this review discusses new conceptual advances that link the immunomodulatory role of F. nucleatum to the development and progression of breast, ovarian, endometrial, and cervical carcinomas through the activation of various direct and indirect signaling pathways. However, further studies are needed to explore and elucidate the highly dynamic process of host-F. nucleatum interactions and discover new pathways, which will pave the way for the development of better preventive and therapeutic strategies against this pathobiont.


Asunto(s)
Fusobacterium nucleatum , Resultado del Embarazo , Humanos , Femenino , Fusobacterium nucleatum/patogenicidad , Embarazo , Infecciones por Fusobacterium/complicaciones , Infecciones por Fusobacterium/microbiología , Enfermedades de los Genitales Femeninos/microbiología , Neoplasias/microbiología
4.
Am J Emerg Med ; 81: 1-9, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38613874

RESUMEN

OBJECTIVE: To assess the association between ambient heat and all-cause and cause-specific emergency department (ED) visits and acute hospitalizations among Medicare beneficiaries in the conterminous United States. DESIGN: Retrospective cohort study. SETTING: Conterminous US from 2008 and 2019. PARTICIPANTS: 2% random sample of all Medicare fee-for-service beneficiaries eligible for Parts A, B, and D. MAIN OUTCOME MEASURES: All-cause and cause-specific (cardiovascular, renal, and heat-related) ED visits and unplanned hospitalizations were identified using primary ICD-9 or ICD-10 diagnosis codes. We measured the association between ambient temperature - defined as daily mean temperature percentile of summer (June through September) - and the outcomes. Hazard ratios and their associated 95% confidence intervals were estimated using multivariable Cox proportional hazards regression, adjusting for individual level demographics, comorbidities, healthcare utilization factors and zip-code level social factors. RESULTS: Among 809,636 Medicare beneficiaries (58% female, 81% non-Hispanic White, 24% <65), older beneficiaries (aged ≥65) exposed to >95th percentile temperature had a 64% elevated adjusted risk of heat-related ED visits (HR [95% CI], 1.64 [1.46,1.85]) and a 4% higher risk of all-cause acute hospitalization (1.04 [1.01,1.06]) relative to <25th temperature percentile. Younger beneficiaries (aged <65) showed increased risk of heat-related ED visits (2.69 [2.23,3.23]) and all-cause ED visits (1.03 [1.01,1.05]). The associations with heat related events were stronger in males and individuals dually eligible for Medicare and Medicaid. No significant differences were observed by climatic region. We observed no significant relationship between temperature percentile and risk of CV-related ED visits or renal-related ED visits. CONCLUSIONS: Among Medicare beneficiaries from 2008 to 2019, exposure to daily mean temperature ≥ 95th percentile was associated with increased risk of heat-related ED visits, with stronger associations seen among beneficiaries <65, males, and patients with low socioeconomic position. Further longitudinal studies are needed to understand the impact of heat duration, intensity, and frequency on cause-specific hospitalization outcomes.


Asunto(s)
Servicio de Urgencia en Hospital , Hospitalización , Medicare , Humanos , Servicio de Urgencia en Hospital/estadística & datos numéricos , Estados Unidos/epidemiología , Femenino , Masculino , Anciano , Hospitalización/estadística & datos numéricos , Medicare/estadística & datos numéricos , Estudios Retrospectivos , Calor/efectos adversos , Anciano de 80 o más Años , Persona de Mediana Edad , Visitas a la Sala de Emergencias
5.
PLoS One ; 19(4): e0297749, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38687749

RESUMEN

Therapeutic options for managing Pancreatic ductal adenocarcinoma (PDAC), one of the deadliest types of aggressive malignancies, are limited and disappointing. Therefore, despite suboptimal clinical effects, gemcitabine (GEM) remains the first-line chemotherapeutic drug in the clinic for PDAC treatment. The therapeutic limitations of GEM are primarily due to poor bioavailability and the development of chemoresistance resulting from the addiction of mutant-K-RAS/AKT/ERK signaling-mediated desmoplastic barriers with a hypoxic microenvironment. Several new therapeutic approaches, including nanoparticle-assisted drug delivery, are being investigated by us and others. This study used pH-responsive nanoparticles encapsulated ERK inhibitor (SCH772984) and surface functionalized with tumor-penetrating peptide, iRGD, to target PDAC tumors. We used a small molecule, SCH772984, to target ERK1 and ERK2 in PDAC and other cancer cells. This nanocarrier efficiently released ERKi in hypoxic and low-pH environments. We also found that the free-GEM, which is functionally weak when combined with nanoencapsulated ERKi, led to significant synergistic treatment outcomes in vitro and in vivo. In particular, the combination approaches significantly enhanced the GEM effect in PDAC growth inhibition and prolonged survival of the animals in a genetically engineered KPC (LSL-KrasG12D/+/LSL-Trp53R172H/+/Pdx-1-Cre) pancreatic cancer mouse model, which is not observed in a single therapy. Mechanistically, we anticipate that the GEM efficacy was increased as ERKi blocks desmoplasia by impairing the production of desmoplastic regulatory factors in PDAC cells and KPC mouse tumors. Therefore, 2nd generation ERKi (SCH 772984)-iRGD-pHNPs are vital for the cellular response to GEM and denote a promising therapeutic target in PDAC with mutant K-RAS.


Asunto(s)
Desoxicitidina , Gemcitabina , Nanopartículas , Neoplasias Pancreáticas , Animales , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Desoxicitidina/administración & dosificación , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Ratones , Humanos , Línea Celular Tumoral , Nanopartículas/química , Concentración de Iones de Hidrógeno , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Modelos Animales de Enfermedad , Microambiente Tumoral/efectos de los fármacos
6.
Clin Epigenetics ; 16(1): 40, 2024 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-38461243

RESUMEN

BACKGROUND: MAL (T-lymphocyte maturation-associated protein) is highly downregulated in most cancers, including cervical cancer (CaCx), attributable to promoter hypermethylation. Long noncoding RNA genes (lncGs) play pivotal roles in CaCx pathogenesis, by interacting with human papillomavirus (HPV)-encoded oncoproteins, and epigenetically regulating coding gene expression. Hence, we attempted to decipher the impact and underlying mechanisms of MAL downregulation in HPV16-related CaCx pathogenesis, by interrogating the interactive roles of MAL antisense lncRNA AC103563.8, E7 oncoprotein and PRC2 complex protein, EZH2. RESULTS: Employing strand-specific RNA-sequencing, we confirmed the downregulated expression of MAL in association with poor overall survival of CaCx patients bearing HPV16, along with its antisense long noncoding RNA (lncRNA) AC103563.8. The strength of positive correlation between MAL and AC103563.8 was significantly high among patients compared to normal individuals. While downregulated expression of MAL was significantly associated with poor overall survival of CaCx patients bearing HPV16, AC103563.8 did not reveal any such association. We confirmed the enrichment of chromatin suppressive mark, H3K27me3 at MAL promoter, using ChIP-qPCR in HPV16-positive SiHa cells. Subsequent E7 knockdown in such cells significantly increased MAL expression, concomitant with decreased EZH2 expression and H3K27me3 marks at MAL promoter. In silico analysis revealed that both E7 and EZH2 bear the potential of interacting with AC103563.8, at the same binding domain. RNA immunoprecipitation with anti-EZH2 and anti-E7 antibodies, respectively, and subsequent quantitative PCR analysis in E7-silenced and unperturbed SiHa cells confirmed the interaction of AC103563.8 with EZH2 and E7, respectively. Apparently, AC103563.8 seems to preclude EZH2 and bind with E7, failing to block EZH2 function in patients. Thereby, enhanced EZH2 expression in the presence of E7 could potentially inactivate the MAL promoter through H3K27me3 marks, corroborating our previous results of MAL expression downregulation in patients. CONCLUSION: AC103563.8-E7-EZH2 axis, therefore, appears to crucially regulate the expression of MAL, through chromatin inactivation in HPV16-CaCx pathogenesis, warranting therapeutic strategy development.


Asunto(s)
Proteínas Proteolipídicas Asociadas a Mielina y Linfocito , Proteínas Oncogénicas Virales , ARN Largo no Codificante , Neoplasias del Cuello Uterino , Femenino , Humanos , Cromatina/metabolismo , Metilación de ADN , Regulación hacia Abajo , Proteína Potenciadora del Homólogo Zeste 2/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Histonas/metabolismo , Papillomavirus Humano 16/genética , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Neoplasias del Cuello Uterino/patología , Proteínas Proteolipídicas Asociadas a Mielina y Linfocito/genética , Proteínas Proteolipídicas Asociadas a Mielina y Linfocito/metabolismo
7.
FASEB J ; 38(6): e23572, 2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38512139

RESUMEN

Asthma is characterized by airway remodeling and hyperreactivity. Our earlier studies determined that the nitric oxide (NO)-soluble guanylyl cyclase (sGC)-cGMP pathway plays a significant role in human lung bronchodilation. However, this bronchodilation is dysfunctional in asthma due to high NO levels, which cause sGC to become heme-free and desensitized to its natural activator, NO. In order to determine how asthma impacts the various lung segments/lobes, we mapped the inflammatory regions of lungs to determine whether such regions coincided with molecular signatures of sGC dysfunction. We demonstrate using murine models of asthma (OVA and CFA/HDM) that the inflamed segments of these murine lungs can be tracked by upregulated expression of HO1 and these regions in turn overlap with regions of heme-free sGC as evidenced by a decreased sGC-α1ß1 heterodimer and an increased response to heme-independent sGC activator, BAY 60-2770, relative to naïve uninflamed regions. We also find that NO generated from iNOS upregulation in the inflamed segments has a higher impact on developing heme-free sGC as increasing iNOS activity correlates linearly with elevated heme-independent sGC activation. This excess NO works by affecting the epithelial lung hemoglobin (Hb) to become heme-free in asthma, thereby causing the Hb to lose its NO scavenging function and exposing the underlying smooth muscle sGC to excess NO, which in turn becomes heme-free. Recognition of these specific lung segments enhances our understanding of the inflamed lungs in asthma with the ultimate aim to evaluate potential therapies and suggest that regional and not global inflammation impacts lung function in asthma.


Asunto(s)
Asma , Hemo-Oxigenasa 1 , Hemo , Animales , Humanos , Ratones , Alérgenos , Hemo-Oxigenasa 1/metabolismo , Inflamación , Óxido Nítrico , Guanilil Ciclasa Soluble
8.
Access Microbiol ; 6(2)2024.
Artículo en Inglés | MEDLINE | ID: mdl-38482345

RESUMEN

Background: Infections caused by Nocardia spp. can occur in immunocompromised as well as immunocompetent individuals. Although nocardiosis is rare, it is being increasingly recognized owing to the rise in occurrence rate over the years. The documentation of pleural involvement in nocardiosis is rare in India. Case: We report a case of pulmonary nocardiosis in an immunocompromised individual caused by Nocardia otitidiscaviarum. Discussion: Pulmonary nocardiosis caused by Nocardia otitidiscaviarum may go unnoticed without clinical suspicion. Correct and timely identification is the key to proper patient management. Conclusion: Coordination between clinicians and microbiologists is necessary for early diagnosis and appropriate management of nocardiosis.

9.
JAMA Netw Open ; 7(3): e242546, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38488792

RESUMEN

Importance: Clinician specialization in the care of nursing home (NH) residents or patients in skilled nursing facilities (SNFs) has become increasingly common. It is not known whether clinicians focused on NH care, often referred to as SNFists (ie, physicians, nurse practitioners, and physician assistants concentrating their practice in the NH or SNF setting), are associated with a reduced likelihood of burdensome transitions in the last 90 days of life for residents, which are a marker of poor-quality end-of-life (EOL) care. Objective: To quantify the association between receipt of care from an SNFist and quality of EOL care for NH residents. Design, Setting, and Participants: This cohort study analyzed Medicare fee-for-service claims for a nationally representative 20% sample of beneficiaries to examine burdensome transitions among NH decedents at the EOL from January 1, 2013, through December 31, 2019. Statistical analyses were conducted from December 2022 to June 2023. Exposure: Receipt of care from an SNFist, defined as physicians and advanced practitioners who provided 80% or more of their evaluation and management visits in NHs annually. Main Outcomes and Measures: This study used augmented inverse probability weighting in analyses of Medicare fee-for-service claims for a nationally representative 20% sample of beneficiaries. Main outcomes included 4 measures of burdensome transitions: (1) hospital transfer in the last 3 days of life; (2) lack of continuity in NHs after hospitalization in the last 90 days of life; (3) multiple hospitalizations in the last 90 days of life for any reason or any hospitalization for pneumonia, urinary tract infection, dehydration, or sepsis; and (4) any hospitalization in the last 90 days of life for an ambulatory care-sensitive condition. Results: Of the 2 091 954 NH decedents studied (mean [SD] age, 85.4 [8.5] years; 1 470 724 women [70.3%]), 953 722 (45.6%) received care from SNFists and 1 138 232 (54.4%) received care from non-SNFists; 422 575 of all decedents (20.2%) experienced a burdensome transition at the EOL. Receipt of care by an SNFist was associated with a reduced risk of (1) hospital transfer in the last 3 days of life (-1.6% [95% CI, -2.5% to -0.8%]), (2) lack of continuity in NHs after hospitalization (-4.8% [95% CI, -6.7% to -3.0%]), and (3) decedents experiencing multiple hospitalizations for any reason or any hospitalization for pneumonia, urinary tract infection, dehydration, or sepsis (-5.8% [95% CI, -10.1% to -1.7%]). There was not a statistically significant association with the risk of hospitalization for an ambulatory care-sensitive condition in the last 90 days of life (0.0% [95% CI, -14.7% to 131.7%]). Conclusions and Relevance: This study suggests that SNFists may be an important resource to improve the quality of EOL care for NH residents.


Asunto(s)
Neumonía , Sepsis , Cuidado Terminal , Infecciones Urinarias , Humanos , Femenino , Anciano , Estados Unidos , Anciano de 80 o más Años , Estudios de Cohortes , Deshidratación , Medicare , Casas de Salud , Neumonía/epidemiología , Neumonía/terapia
10.
Carcinogenesis ; 45(7): 451-462, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38446431

RESUMEN

Long intergenic noncoding RNAs (lincRNAs) do not overlap annotated coding genes and are located in intergenic regions, as opposed to antisense and sense-intronic lncRNAs, located in genic regions. LincRNAs influence gene expression profiles and are thereby key to disease pathogenesis. In this study, we assessed the association between lincRNAs and HPV16-positive cervical cancer (CaCx) pathogenesis using weighted gene co-expression network analysis (WGCNA) with coding genes, comparing differentially expressed lincRNA and coding genes (DElincGs and DEcGs, respectively) in HPV16-positive patients with CaCx (n = 44) with those in HPV-negative healthy individuals (n = 34). Our analysis revealed five DElincG modules, co-expressing and correlating with DEcGs. We validated a substantial number of such module-specific correlations in the HPV16-positive cancer TCGA-CESC dataset. Four such modules, displayed significant correlations with patient traits, such as HPV16 physical status, lymph node involvement and overall survival (OS), highlighting a collaborative effect of all genes within specific modules on traits. Using the DAVID bioinformatics knowledgebase, we identified the underlying biological processes associated with these modules as cancer development and progression-associated pathways. Next, we identified the top 10 DElincGs with the highest connectivity within each functional module. Focusing on the prognostic module hub genes, downregulated CTD-2619J13.13 expression was associated with poor patient OS. This lincRNA gene interacted with 25 coding genes of its module and was associated with such biological processes as keratinization loss and keratinocyte differentiation, reflecting severe disease phenotypes. This study has translational relevance in fighting various cancers with high mortality rates in underdeveloped countries.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Papillomavirus Humano 16 , Infecciones por Papillomavirus , ARN Largo no Codificante , Neoplasias del Cuello Uterino , Humanos , ARN Largo no Codificante/genética , Femenino , Neoplasias del Cuello Uterino/virología , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patología , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/patogenicidad , Infecciones por Papillomavirus/virología , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/patología , Perfilación de la Expresión Génica , Pronóstico , Biomarcadores de Tumor/genética
11.
J Gen Intern Med ; 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38424345

RESUMEN

Building expertise in climate and planetary health among healthcare professionals cannot come with greater urgency as the threats from climate change become increasingly apparent. Current and future healthcare professionals-particularly internists-will increasingly need to understand the interconnectedness of natural systems and human health to better serve their patients longitudinally. Despite this, few national medical societies and accreditation bodies espouse frameworks for climate change and planetary health-related education at the undergraduate (UME), graduate (GME), and continuing (CME) medical education level. As a community of medical educators with an enduring interest in climate change and planetary health, the Society of General Internal Medicine (SGIM) recognizes the need to explicitly define structured educational opportunities and core competencies in both UME and GME as well as pathways for faculty development. In this position statement, we build from the related SGIM Climate and Health position statement, and review and synthesize existing position statements made by US-based medical societies and accreditation bodies that focus on climate change and planetary health-related medical education, identify gaps using Bloom's Hierarchy, and provide recommendations on behalf of SGIM regarding the development of climate and planetary health curricula development. Identified gaps include (1) limited systematic approach to climate and planetary health medical education at all levels; (2) minimal emphasis on learner-driven approaches; (3) limited focus on physician and learner well-being; and (4) limited role for health equity and climate justice. Recommendations include a call to relevant accreditation bodies to explicitly include climate change and planetary health as a competency, extend the structural competency framework to climate change and planetary health to build climate justice, proactively include learners in curricular development and teaching, and ensure resources and support to design and implement climate and planetary health-focused education that includes well-being and resiliency.

12.
Curr Microbiol ; 81(4): 95, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38353761

RESUMEN

The present work was carried out during the emergence of Delta Variant of Concern (VoC) and aimed to study the change in SARS CoV-2 viral load in Covishield vaccinated asymptomatic/mildly symptomatic health-care workers (HCWs) to find out the optimum isolation period. The SARS CoV-2 viral load was carried out in sequential samples of 55 eligible HCWs which included unvaccinated (UnV; n = 11), single-dose vaccinated (SDV, n = 20) and double-dose vaccinated [DDV, n = 24; short-interval (<6 weeks)] subjects. The mean load of envelope (E) gene on day 5 in SDV [0.42 × 105 copies/reaction] was significantly lower as compared to DDV [6.3 × 105 copies/reaction, P = 0.005] and UnV [6.6 × 105 copies/reaction, P = 0.001] groups. The rate of decline of SARS CoV-2 viral load in the initial 5 days of PCR positivity was significantly higher in SDV as compared to that in DDV (Mean log decline 0.39 vs. 0.19; P < 0.001). This was possibly due to interference of adenoviral immunity of first dose of adenovirus-vectored vaccine in double-dose vaccinated HCWs who had received vaccines within a shorter interval (<6 weeks).


Asunto(s)
COVID-19 , ChAdOx1 nCoV-19 , Humanos , SARS-CoV-2/genética , Carga Viral , COVID-19/prevención & control
13.
ACS Appl Bio Mater ; 7(3): 1790-1800, 2024 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-38424007

RESUMEN

A sustainable approach for pharmaceutically important pyrimidine derivatives is achieved by using biogenically produced single-phase δ-MnO2 NPs under external ligand-free conditions. The phytochemicals that comprise the extract of Areca Nut Husk (ANH) have been discovered to serve as reducing agents. The role of phytochemicals is not only to aid in the reduction of Mn(VII) into Mn(IV), but they also have an important role in stabilizing the catalyst. The establishment of δ-MnO2 NPs was confirmed inveterate by FE-SEM, p-XRD, ICP-OES (Mn content = 43.17% w/w), EDX, and with an active Mn content of 43.17% w/w. A series of pyrimidine derivatives were prepared in good yields using a one-pot multicomponent synthesis approach under atmospheric conditions. In addition, hot filtration tests, control experiments, gram-scale synthesis, and mechanistic investigations were demonstrated. Additionally, antimicrobial activity studies of δ-MnO2 NPs and pyrimidine derivatives against the Gram-negative bacteria E. coli, growth curve and minimum inhibitory concentration were studied.


Asunto(s)
Antiinfecciosos , Nanopartículas , Escherichia coli , Compuestos de Manganeso/farmacología , Óxidos , Nanopartículas/uso terapéutico , Pirimidinas/farmacología , Antiinfecciosos/farmacología
14.
J Phys Chem Lett ; 15(6): 1702-1707, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38316135

RESUMEN

Semiconductor quantum dots are characterized by a discrete excitonic structure featuring coarse as well as fine structure. The lowest fine structure states have splittings into bright-dark states which are now well confirmed by single dot spectroscopy. In contrast, the splitting of the lowest coarse exciton into bright-bright fine structure states has not been observed nor the dynamics between these states. Here, we use the unique combination of time and energy resolution of two-dimensional electronic spectroscopy to directly observe the fine structure splittings into a bright-bright doublet. These splittings are strongly size dependent, with population relaxation on the <100 fs time scale.

15.
Int J Biol Macromol ; 260(Pt 2): 129151, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38181914

RESUMEN

Growth factors play a pivotal role in orchestrating cellular growth and division by binding to specific cell surface receptors. Dysregulation of growth factor production or activity can contribute to the uncontrolled cell proliferation observed in cancer. Peptide-based nanoformulations (PNFs) have emerged as promising therapeutic strategies for growth factor-deficient cancers. PNFs offer multifaceted capabilities including targeted delivery, imaging modalities, combination therapies, resistance modulation, and personalized medicine approaches. Nevertheless, several challenges remain, including limited specificity, stability, pharmacokinetics, tissue penetration, toxicity, and immunogenicity. To address these challenges and optimize PNFs for clinical translation, in-depth investigations are warranted. Future research should focus on elucidating the intricate interplay between peptides and nanoparticles, developing robust spectroscopic and computational methodologies, and establishing a comprehensive understanding of the structure-activity relationship governing peptide-nanoparticle interactions. Bridging these knowledge gaps will propel the translation of peptide-nanoparticle therapies from bench to bedside. While a few peptide-nanoparticle drugs have obtained FDA approval for cancer treatment, the integration of nanostructured platforms with peptide-based medications holds tremendous potential to expedite the implementation of innovative anticancer interventions. Therefore, growth factor-deficient cancers present both challenges and opportunities for targeted therapeutic interventions, with peptide-based nanoformulations positioned as a promising avenue. Nonetheless, concerted research and development endeavors are essential to optimize the specificity, stability, and safety profiles of PNFs, thereby advancing the field of peptide-based nanotherapeutics in the realm of oncology research.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Medicina de Precisión/métodos , Sistemas de Liberación de Medicamentos , Nanomedicina/métodos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Nanopartículas/química , Péptidos/uso terapéutico , Péptidos y Proteínas de Señalización Intercelular
16.
Diabetes Care ; 47(2): 233-238, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38060348

RESUMEN

OBJECTIVE: To measure the association between ambient heat and hypoglycemia-related emergency department visit or hospitalization in insulin users. RESEARCH DESIGN AND METHODS: We identified cases of serious hypoglycemia among adults using insulin aged ≥65 in the U.S. (via Medicare Part A/B/D-eligible beneficiaries) and Taiwan (via National Health Insurance Database) from June to September, 2016-2019. We then estimated odds of hypoglycemia by heat index (HI) percentile categories using conditional logistic regression with a time-stratified case-crossover design. RESULTS: Among ∼2 million insulin users in the U.S. (32,461 hypoglycemia case subjects), odds ratios of hypoglycemia for HI >99th, 95-98th, 85-94th, and 75-84th percentiles compared with the 25-74th percentile were 1.38 (95% CI, 1.28-1.48), 1.14 (1.08-1.20), 1.12 (1.08-1.17), and 1.09 (1.04-1.13) respectively. Overall patterns of associations were similar for insulin users in the Taiwan sample (∼283,000 insulin users, 10,162 hypoglycemia case subjects). CONCLUSIONS: In two national samples of older insulin users, higher ambient temperature was associated with increased hypoglycemia risk.


Asunto(s)
Diabetes Mellitus , Hipoglucemia , Anciano , Humanos , Estados Unidos/epidemiología , Insulina/efectos adversos , Estudios Cruzados , Hipoglucemiantes , Calor , Taiwán/epidemiología , Estudios Retrospectivos , Medicare , Hipoglucemia/inducido químicamente , Hipoglucemia/epidemiología , Insulina Regular Humana
17.
JAMA Cardiol ; 9(1): 55-62, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38055247

RESUMEN

Importance: Use of race-specific risk prediction in clinical medicine is being questioned. Yet, the most commonly used prediction tool for atherosclerotic cardiovascular disease (ASCVD)-pooled cohort risk equations (PCEs)-uses race stratification. Objective: To quantify the incremental value of race-specific PCEs and determine whether adding social determinants of health (SDOH) instead of race improves model performance. Design, Setting, and Participants: Included in this analysis were participants from the biracial Reasons for Geographic and Racial Differences in Stroke (REGARDS) prospective cohort study. Participants were aged 45 to 79 years, without ASCVD, and with low-density lipoprotein cholesterol level of 70 to 189 mg/dL or non-high-density lipoprotein cholesterol level of 100 to 219 mg/dL at baseline during the period of 2003 to 2007. Participants were followed up to 10 years for incident ASCVD, including myocardial infarction, coronary heart disease death, and fatal and nonfatal stroke. Study data were analyzed from July 2022 to February 2023. Main outcome/measures: Discrimination (C statistic, Net Reclassification Index [NRI]), and calibration (plots, Nam D'Agostino test statistic comparing observed to predicted events) were assessed for the original PCE, then for a set of best-fit, race-stratified equations including the same variables as in the PCE (model C), best-fit equations without race stratification (model D), and best-fit equations without race stratification but including SDOH as covariates (model E). Results: This study included 11 638 participants (mean [SD] age, 61.8 [8.3] years; 6764 female [58.1%]) from the REGARDS cohort. Across all strata (Black female, Black male, White female, and White male participants), C statistics did not change substantively compared with model C (Black female, 0.71; 95% CI, 0.68-0.75; Black male, 0.68; 95% CI, 0.64-0.73; White female, 0.77; 95% CI, 0.74-0.81; White male, 0.68; 95% CI, 0.64-0.71), in model D (Black female, 0.71; 95% CI, 0.67-0.75; Black male, 0.68; 95% CI, 0.63-0.72; White female, 0.76; 95% CI, 0.73-0.80; White male, 0.68; 95% CI, 0.65-0.71), or in model E (Black female, 0.72; 95% CI, 0.68-0.76; Black male, 0.68; 95% CI, 0.64-0.72; White female, 0.77; 95% CI, 0.74-0.80; White male, 0.68; 95% CI, 0.65-0.71). Comparing model D with E using the NRI showed a net percentage decline in the correct assignment to higher risk for male but not female individuals. The Nam D'Agostino test was not significant for all race-sex strata in each model series, indicating good calibration in all groups. Conclusions: Results of this cohort study suggest that PCE performed well overall but had poorer performance in both BM and WM participants compared with female participants regardless of race in the REGARDS cohort. Removal of race or the addition of SDOH did not improve model performance in any subgroup.


Asunto(s)
Aterosclerosis , Enfermedades Cardiovasculares , Racismo , Accidente Cerebrovascular , Humanos , Masculino , Femenino , Persona de Mediana Edad , Enfermedades Cardiovasculares/epidemiología , Factores de Riesgo , Estudios de Cohortes , Estudios Prospectivos , Determinantes Sociales de la Salud , Medición de Riesgo/métodos , Aterosclerosis/epidemiología , Accidente Cerebrovascular/epidemiología
18.
Indian J Pediatr ; 91(4): 329-336, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37870740

RESUMEN

OBJECTIVES: To study the epidemiology of non-coronavirus disease-2019 (non-COVID-19) respiratory viral infections with respect to their clinical profile, intensive care needs and predictors of outcome once the non-pharmacological interventions (NPI) during the coronavirus disease-2019 (COVID-19) pandemic were relaxed. METHODS: Retrospective analysis of children with Severe Acute Respiratory Illness (SARI) who were SARS-CoV-2 negative, admitted to the Pediatric Emergency/Intensive Care Unit (PICU) from July 2021 through October 2021 was conducted. RESULTS: One hundred and thirty nine children with median age of 11 (4-28.5) mo were included. Besides respiratory symptoms in all, diarrhea was reported in 90 (64.7%) children. Nearly half (n = 66; 47%) presented in hypoxemic respiratory failure (SpO2 <88%). Fifty-two (37.4%) children had co-morbidities, commonest being congenital heart disease in 12 (23.1%). Baseline parameters revealed leukopenia (specifically lymphopenia) 39 (28%), elevated aspartate transaminase [Serum glutamic-oxaloacetic transaminase (SGOT)] in 108 (77.6%), elevated N-acetyl-cysteine-activated creatinine kinase (CK-NAC) 23 (79%) and lactate dehydrogenase (LDH) 15 (88%). Intensive care needs included mechanical ventilation 51 (36.6%), vasoactive support 34 (24.5%), and renal replacement therapy 10 (7.1%). Forty-two (30.2%) children developed multi-organ dysfunction syndrome (MODS). One hundred and three (74.1%) children were discharged, 31 (22.3%) died, and 5 (3.6%) left against medical advice. On multivariate regression analysis, elevated liver enzymes (>5 times normal), hypoxemic respiratory failure at admission, hypotensive shock and MODS predicted mortality. CONCLUSIONS: A surge in non-COVID SARI was observed once lockdown measures were relaxed. Nearly 1/3rd progressed to multi-organ failure and died. Elevated liver enzymes, hypoxemic respiratory failure at admission, hypotensive shock and MODS predicted death.


Asunto(s)
COVID-19 , Insuficiencia Respiratoria , Niño , Humanos , SARS-CoV-2 , Pandemias , Estudios Retrospectivos , Cuidados Críticos
19.
ACS Nano ; 18(1): 1054-1062, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38109401

RESUMEN

The idea of phonon bottlenecks has long been pursued in nanoscale materials for their application in hot exciton devices, such as photovoltaics. Decades ago, it was shown that there is no quantum phonon bottleneck in strongly confined quantum dots due to their physics of quantum confinement. More recently, it was proposed that there are hot phonon bottlenecks in metal halide perovskites due to their physics. Recent work has called into question these bottlenecks in metal halide perovskites. Here, we compare hot exciton cooling in a range of sizes of CsPbBr3 nanocrystals from weakly to strongly confined. These results are compared to strongly confined CdSe quantum dots of two sizes and degrees of quantum confinement. CdSe is a model system as a ruler for measuring hot exciton cooling being fast, by virtue of its efficient Auger-assisted processes. By virtue of 3 ps time resolution, the hot exciton photoluminescence can now be directly observed, which is the most direct measure of the presence of hot excitons and their lifetimes. The hot exciton photoluminescence decays on nearly the same 2 ps time scale on both the weakly confined perovskite and the larger CdSe quantum dots, much faster than the 10 ps cooling predicted by transient absorption experiments. The smaller CdSe quantum dot has still faster cooling, as expected from quantum size effects. The quantum dots of perovskites show extremely fast hot exciton cooling, decaying faster than detection limits of <1 ps, even faster than the CdSe system, suggesting the efficiency of Auger processes in these metal halide perovskite nanocrystals and especially in their quantum dot form. These results across a range of sizes of nanocrystals reveal extremely fast hot exciton cooling at high exciton density, independent of composition, but dependent upon size. Hence these metal halide perovskite nanocrystals seem to cool heavily following quantum dot physics.

20.
bioRxiv ; 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38076947

RESUMEN

Asthma is characterized by airway remodeling and hyperreactivity. Our earlier studies determined that the Nitric Oxide (NO)-soluble Guanylyl Cyclase (sGC)-cGMP pathway plays a significant role in human lung bronchodilation. However this bronchodilation is dysfunctional in asthma due to high NO levels which cause sGC to become heme-free and desensitized to its natural activator, NO. In order to determine how asthma impacts the various lung segments/lobes we mapped the inflammatory regions of lungs to determine whether such regions coincided with molecular signatures of sGC dysfunction. We demonstrate using models of mouse asthma (OVA, CFA/HDM) that the inflammed segments of the mouse asthma lungs can be tracked by upregulated expression of HO1 and these regions in-turn overlap with regions of heme-free sGC as evidenced by a decreased sGC-α1ß1 heterodimer and an increased response to heme-independent sGC activator, BAY 60-2770 relative to naïve uninflamed regions. We also find that NO generated from iNOS upregulation in the inflamed segments has a higher impact in developing heme-free sGC as increasing iNOS activity correlates linearly with elevated heme-independent sGC activation. This excess NO works by affecting the epithelial lung hemoglobin (Hb) to become heme-free in asthma thereby causing the Hb to lose its NO scavenging function and exposing the underlying smooth muscle sGC to excess NO, which in-turn becomes heme-free. Recognition of these specific lung segments enhance our understanding of the inflammed lungs in asthma with the ultimate aim to evaluate potential therapies and suggests that regional and not global inflammation impacts lung function in asthma.

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