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1.
Proc Natl Acad Sci U S A ; 121(10): e2319366121, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38422020

RESUMEN

Acute myeloid leukemia (AML) is an aging-related and heterogeneous hematopoietic malignancy. In this study, a total of 1,474 newly diagnosed AML patients with RNA sequencing data were enrolled, and targeted or whole exome sequencing data were obtained in 94% cases. The correlation of aging-related factors including age and clonal hematopoiesis (CH), gender, and genomic/transcriptomic profiles (gene fusions, genetic mutations, and gene expression networks or pathways) was systematically analyzed. Overall, AML patients aged 60 y and older showed an apparently dismal prognosis. Alongside age, the frequency of gene fusions defined in the World Health Organization classification decreased, while the positive rate of gene mutations, especially CH-related ones, increased. Additionally, the number of genetic mutations was higher in gene fusion-negative (GF-) patients than those with GF. Based on the status of CH- and myelodysplastic syndromes (MDS)-related mutations, three mutant subgroups were identified among the GF- AML cohort, namely, CH-AML, CH-MDS-AML, and other GF- AML. Notably, CH-MDS-AML demonstrated a predominance of elderly and male cases, cytopenia, and significantly adverse clinical outcomes. Besides, gene expression networks including HOXA/B, platelet factors, and inflammatory responses were most striking features associated with aging and poor prognosis in AML. Our work has thus unraveled the intricate regulatory circuitry of interactions among different age, gender, and molecular groups of AML.


Asunto(s)
Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Anciano , Humanos , Masculino , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Envejecimiento/genética , Mutación , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/patología , Pronóstico
2.
Chem Rev ; 124(6): 2955-3012, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38478971

RESUMEN

The structure of catalysts determines the performance of catalytic processes. Intrinsically, the electronic and geometric structures influence the interaction between active species and the surface of the catalyst, which subsequently regulates the adsorption, reaction, and desorption behaviors. In recent decades, the development of catalysts with complex structures, including bulk, interfacial, encapsulated, and atomically dispersed structures, can potentially affect the electronic and geometric structures of catalysts and lead to further control of the transport and reaction of molecules. This review describes comprehensive understandings on the influence of electronic and geometric properties and complex catalyst structures on the performance of relevant heterogeneous catalytic processes, especially for the transport and reaction over structured catalysts for the conversions of light alkanes and small molecules. The recent research progress of the electronic and geometric properties over the active sites, specifically for theoretical descriptors developed in the recent decades, is discussed at the atomic level. The designs and properties of catalysts with specific structures are summarized. The transport phenomena and reactions over structured catalysts for the conversions of light alkanes and small molecules are analyzed. At the end of this review, we present our perspectives on the challenges for the further development of structured catalysts and heterogeneous catalytic processes.

3.
BMC Plant Biol ; 24(1): 167, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438916

RESUMEN

BACKGROUND: Generating elite rice varieties with high yield and superior quality is the main goal of rice breeding programs. Key agronomic traits, including grain size and seed germination characteristics, affect the final yield and quality of rice. The RGA1 gene, which encodes the α-subunit of rice G-protein, plays an important role in regulating rice architecture, seed size and abiotic stress responses. However, whether RGA1 is involved in the regulation of rice quality and seed germination traits is still unclear. RESULTS: In this study, a rice mutant small and round grain 5 (srg5), was identified in an EMS-induced rice mutant library. Systematic analysis of its major agronomic traits revealed that the srg5 mutant exhibited a semi-dwarf plant height with small and round grain and reduced panicle length. Analysis of the physicochemical properties of rice showed that the difference in rice eating and cooking quality (ECQ) between the srg5 mutant and its wild-type control was small, but the appearance quality was significantly improved. Interestingly, a significant suppression of rice seed germination and shoot growth was observed in the srg5 mutant, which was mainly related to the regulation of ABA metabolism. RGA1 was identified as the candidate gene for the srg5 mutant by BSA analysis. A SNP at the splice site of the first intron disrupted the normal splicing of the RGA1 transcript precursor, resulting in a premature stop codon. Additional linkage analysis confirmed that the target gene causing the srg5 mutant phenotype was RGA1. Finally, the introduction of the RGA1 mutant allele into two indica rice varieties also resulted in small and round rice grains with less chalkiness. CONCLUSIONS: These results indicate that RGA1 is not only involved in the control of rice architecture and grain size, but also in the regulation of rice quality and seed germination. This study sheds new light on the biological functions of RGA1, thereby providing valuable information for future systematic analysis of the G-protein pathway and its potential application in rice breeding programs.


Asunto(s)
Oryza , Oryza/genética , Semillas/genética , Germinación/genética , Fitomejoramiento , Grano Comestible/genética , Proteínas de Unión al GTP
4.
BMC Geriatr ; 24(1): 599, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38997670

RESUMEN

OBJECTIVES: This review aims to comprehensively summarize the differences in anticholinergic drug burden (ADB) scores between older hospitalized patients with and without delirium. METHODS: We searched PubMed, Embase, Web of Science, Cochrane Library and CINAHL EBSCOhost databases to identify prospective cohort studies exploring the relationship between ADB and the occurrence of delirium in older hospitalized patients. The primary outcome of the review was the mean ADB scores for the delirium and non-delirium groups, and the secondary outcome was the scores for the subsyndromal and non-delirium groups. The standardized mean difference (SMD) and corresponding 95% confidence intervals (95% CI) were incorporated using a fixed-effect method. Moreover, we performed subgroup analysis according to the admission type, age, the ADB scale type and the ADB classification. RESULTS: Nine prospective cohort studies involving 3791 older patients with a median age of 75.1 (71.6-83.9) were included. The ADB score was significantly higher in the delirium group than in the non-delirium group (SMD = 0.21, 95%CI 0.13-0.28). In subgroup analysis, the age subgroup was split into < 75 and ≥ 75 according to the median age of the older people. There were significant differences in ADB scores between older people with delirium and those without delirium in various subgroups: surgical (SMD = 0.20, 95%CI 0.12-0.28), internal medicine (SMD = 0.64, 95%CI 0.25-1.02), age < 75 (SMD = 0.17, 95%CI 0.08-0.26), age ≥ 75 (SMD = 0.27, 95%CI 0.15-0.39), ADS scale (SMD = 0.13, 95%CI 0.13-0.40), ARS scale (SMD = 0.15, 95%CI 0.03-0.26), ACB scale (SMD = 0.13, 95%CI 0.01-0.25), pre-admission ADB (SMD = 0.24, 95%CI 0.05-0.43) and ADB during hospitalization (SMD = 0.20, 95%CI 0.12-0.27). CONCLUSIONS: We found a quantitative relationship between ADB and delirium in older patients admitted for internal medicine and surgery. And this relationship remained significant in different age, ADB scale type and ADB classification subgroups. However, the actual difference in ADB scores between patients with delirium and without delirium was small. More high-quality observational studies should be conducted to explore the impact of ADB on delirium and subsyndromal delirium. CLINICAL TRIAL REGISTRATION: The protocol was published in the International Prospective Register of Systematic Reviews (PROSPERO) [Ref: CRD42022353649].


Asunto(s)
Antagonistas Colinérgicos , Delirio , Hospitalización , Humanos , Delirio/epidemiología , Antagonistas Colinérgicos/efectos adversos , Antagonistas Colinérgicos/uso terapéutico , Anciano , Estudios Prospectivos , Anciano de 80 o más Años , Estudios de Cohortes
5.
BMC Pediatr ; 24(1): 473, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39049018

RESUMEN

OBJECTIVE: Laparoscopic choledochectomy and hepatojejunostomy have been reported in children since 1995, but this procedure is technically demanding. Robotic surgical systems can simplify complex minimally invasive procedures. Currently, few reports have been made on neonates. We present the experience of 6 cases of neonatal CC(choledochal cysts). STUDY DESIGN: Between January 2022 and December 2023, 6 neonates underwent robotic resection of choledochal cyst and hepaticojejunostomy using the Da Vinci surgical system at Children's Hospital, Zhejiang University School of Medicine, a high-volume hepatobiliary disease center. demographic data of the patients and surgical outcomes were collected and analyzed. RESULTS: All 6 patients were successfully treated by robotic cystectomy and hepaticojejunostomy. The mean age was 17.3 days (range 4-25) and the mean weight was 3.6 kg (range 2.55-4.4). 5 cysts were type Ia and 1 was type Iva. The mean diameter of the cysts was 3.8 cm (range 1.25-5). The mean time to establish feeding was 4.83 days (range 4-6), and patients were discharged after a median time of 16.83 days (range 7-42) without postoperative complications. CONCLUSIONS: This procedure is safe and effective for neonates. The authors found that the use of robot-assisted surgery has ergonomic advantages in this delicate, minimally invasive procedure.


Asunto(s)
Quiste del Colédoco , Procedimientos Quirúrgicos Robotizados , Humanos , Quiste del Colédoco/cirugía , Procedimientos Quirúrgicos Robotizados/métodos , Recién Nacido , Masculino , Femenino , Yeyunostomía/métodos , Laparoscopía/métodos , Estudios Retrospectivos , Resultado del Tratamiento
6.
BMC Pediatr ; 24(1): 124, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38365624

RESUMEN

BACKGROUND: Trichobezoar is an extremely rare condition characterized by a foreign body in the gastrointestinal tract (GIT) among children. The foreign body may exist in the digestive tract for several years, and it becomes evident if complications develop. The current study aimed to present 21 cases of GIT trichobezoars. METHODS: Retrospective analysis of children who were diagnosed with trichobezoars between August 2012 and December 2022. Patient demographics, clinical presentation, diagnosis, and therapy were collected and analyzed.Twenty-one patients had GIT trichobezoars. Data were collected and analyzed retrospectively. RESULTS: Twenty-one patients were identified. All patients were female. Their mean age at admission was 8.9 ± 1.9 years. Furthermore, 19 (90.5%) patients presented with abdominal pain, 16 (76.2%) with vomiting, and 13 (61.9%) with a palpable mass. Sixteen patients underwent gastroduodenoscopy. Among them, 15 had gastric trichobezoars. Moreover, 12 patients underwent computed tomography scan. Eight patients presented with gastric and small intestinal BZs, one presented with increased small intestinal contents with dilation, and one presented with abundant gastric contents. Then, 20 patients underwent surgery. Among them, five underwent laparoscopic-assisted minilaparotomy (LAML), and the rest underwent laparotomy. The results showed that 10 (50%) patients had gastric trichobezoars; 7 (35%), Rapunzel syndrome; and 3 (15%), small bowel trichobezoars. Two patients developed superficial wound infection postoperatively. One patient had a recurrent gastric trichobezoar. CONCLUSION: Trichobezoar should be considered in young girls with a history of hair eating or those with hair in the vomit or feces. Timely diagnosis and aggressive treatment are the keys to reducing complications and improving prognosis. Laparoscopic-assisted minilaparotomy is a safe, feasible, and effective surgical method for treating trichobezoars.


Asunto(s)
Bezoares , Humanos , Femenino , Niño , Masculino , Bezoares/diagnóstico por imagen , Bezoares/cirugía , Estudios Retrospectivos , Estómago/cirugía , Intestino Delgado , Gastroscopía
7.
J Environ Sci (China) ; 143: 1-11, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38644008

RESUMEN

Potential health risks related to environmental endocrine disruptors (EEDs) have aroused research hotspots at the forefront of water treatment technologies. Herein, nitrogen-doped titanium dioxide/schwertmannite nanocomposites (N-TiO2/SCH) have been successfully developed as heterogeneous catalysts for the degradation of typical EEDs via photo-Fenton processes. Due to the sustainable Fe(III)/Fe(II) conversion induced by photoelectrons, as-prepared N-TiO2/SCH nanocomposites exhibit much enhanced efficiency for the degradation of bisphenol A (BPA; ca. 100% within 60 min under visible irradiation) in a wide pH range of 3.0-7.8, which is significantly higher than that of the pristine schwertmannite (ca. 74.5%) or N-TiO2 (ca. 10.8%). In this photo-Fenton system, the efficient degradation of BPA is mainly attributed to the oxidation by hydroxyl radical (•OH) and singlet oxygen (1O2). Moreover, the possible catalytic mechanisms and reaction pathway of BPA degradation are systematically investigated based on analytical and photoelectrochemical analyses. This work not only provides a feasible means for the development of novel heterogeneous photo-Fenton catalysts, but also lays a theoretical foundation for the potential application of mineral-based materials in wastewater treatment.


Asunto(s)
Compuestos de Bencidrilo , Compuestos de Hierro , Nanocompuestos , Nitrógeno , Fenoles , Titanio , Contaminantes Químicos del Agua , Titanio/química , Compuestos de Bencidrilo/química , Fenoles/química , Nanocompuestos/química , Contaminantes Químicos del Agua/química , Nitrógeno/química , Catálisis , Hierro/química , Peróxido de Hidrógeno/química , Disruptores Endocrinos/química , Purificación del Agua/métodos
8.
J Pediatr (Rio J) ; 100(4): 399-405, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38582497

RESUMEN

OBJECTIVE: Ovarian torsion (OT) represents a severe gynecological emergency in female pediatric patients, necessitating immediate surgical intervention to prevent ovarian ischemia and preserve fertility. Prompt diagnosis is, therefore, paramount. This retrospective study set out to assess the utility of combined clinical, ultrasound, and laboratory features in diagnosing OT. METHODS: The authors included 326 female pediatric patients aged under 14 years who underwent surgical confirmation of OT over a five-year period. Logistic regression analysis was employed to pinpoint factors linked with OT, and the authors compared clinical presentation, laboratory results, and ultrasound characteristics between patients with OT (OT group) and without OT (N-OT group). The authors conducted receiver operating characteristic (ROC) curve analysis to gauge the predictive capacity of the combined features. RESULTS: Among 326, OT was confirmed in 24.23 % (79 cases) of the patients. The OT group had a higher incidence of prenatal ovarian masses than the N-OT (22 cases versus 7 cases) (p < 0.0001). Similarly, the authors observed significant differences in the presence of lower abdominal pain, suspected torsion on transabdominal ultrasound, and a high neutrophil-lymphocyte ratio (NLR > 3) between the OT and non-OT groups (p ˂ 0.05). Furthermore, when these parameters were combined, the resulting area under the curve (AUC) was 0.868, demonstrating their potential utility in OT diagnosis. CONCLUSION: This study demonstrates a prediction model integrating clinical, laboratory, and ultrasound findings that can support the preoperative diagnosis of ovarian torsion, thereby enhancing diagnostic precision and improving patient management. Future prospective studies should concentrate on developing clinical predictive models for OT in pediatric patients.


Asunto(s)
Torsión Ovárica , Ultrasonografía , Humanos , Femenino , Torsión Ovárica/diagnóstico , Niño , Estudios Retrospectivos , Adolescente , Preescolar , Curva ROC , Lactante , Valor Predictivo de las Pruebas , Modelos Logísticos , Anomalía Torsional/diagnóstico , Anomalía Torsional/diagnóstico por imagen
9.
JMIR Hum Factors ; 11: e57670, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39146009

RESUMEN

BACKGROUND: The rapid growth of web-based medical services has highlighted the significance of smart triage systems in helping patients find the most appropriate physicians. However, traditional triage methods often rely on department recommendations and are insufficient to accurately match patients' textual questions with physicians' specialties. Therefore, there is an urgent need to develop algorithms for recommending physicians. OBJECTIVE: This study aims to develop and validate a patient-physician hybrid recommendation (PPHR) model with response metrics for better triage performance. METHODS: A total of 646,383 web-based medical consultation records from the Internet Hospital of the First Affiliated Hospital of Xiamen University were collected. Semantic features representing patients and physicians were developed to identify the set of most similar questions and semantically expand the pool of recommended physician candidates, respectively. The physicians' response rate feature was designed to improve candidate rankings. These 3 characteristics combine to create the PPHR model. Overall, 5 physicians participated in the evaluation of the efficiency of the PPHR model through multiple metrics and questionnaires as well as the performance of Sentence Bidirectional Encoder Representations from Transformers and Doc2Vec in text embedding. RESULTS: The PPHR model reaches the best recommendation performance when the number of recommended physicians is 14. At this point, the model has an F1-score of 76.25%, a proportion of high-quality services of 41.05%, and a rating of 3.90. After removing physicians' characteristics and response rates from the PPHR model, the F1-score decreased by 12.05%, the proportion of high-quality services fell by 10.87%, the average hit ratio dropped by 1.06%, and the rating declined by 11.43%. According to whether those 5 physicians were recommended by the PPHR model, Sentence Bidirectional Encoder Representations from Transformers achieved an average hit ratio of 88.6%, while Doc2Vec achieved an average hit ratio of 53.4%. CONCLUSIONS: The PPHR model uses semantic features and response metrics to enable patients to accurately find the physician who best suits their needs.


Asunto(s)
Médicos , Semántica , Humanos , Triaje/métodos , Triaje/normas , Encuestas y Cuestionarios , Algoritmos
10.
Paediatr Int Child Health ; 44(2): 73-78, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39066724

RESUMEN

Trichobezoars are conglomerates of hair within the gastro-intestinal tract, commonly detected in the stomach, and they can present with the Rapunzel syndrome. Isolated small-bowel trichobezoars are extremely rare. Three female patients presented with abdominal pain and bilious vomiting, and underwent various imaging examinations. Two were diagnosed with small-bowel trichobezoars with intestinal obstruction and one with intestinal obstruction only. All three underwent surgery. Two underwent laparoscopic exploration and one underwent a laparotomy. One and two patients had isolated small-bowel trichobezoars in the ileum and jejunum, respectively. Two patients were followed up by a psychiatrist, and all recovered well without recurrence. These three cases emphasise the importance of a comprehensive medical history and imaging in patients with small-bowel obstruction to determine the possibility of bezoars.


Asunto(s)
Bezoares , Obstrucción Intestinal , Humanos , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Femenino , Bezoares/complicaciones , Bezoares/cirugía , Bezoares/diagnóstico por imagen , Niño , Intestino Delgado/patología , Intestino Delgado/diagnóstico por imagen , Adolescente , Laparoscopía , Laparotomía
11.
Sci Total Environ ; 923: 171417, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38447725

RESUMEN

The water-level fluctuations zones (WLFZs) are crucial transitional interfaces within river-reservoir systems, serving as hotspots for N2O emission. However, the comprehension of response patterns and mechanisms governing N2O emission under hydrological fluctuation remains limited, especially in karstic canyon reservoirs, which introduces significant uncertainty to N2O flux assessments. Soil samples were collected from the WLFZs of the Hongjiadu (HJD) Reservoir along the water flow direction from transition zone (T1 and T2) to lacustrine zone (T3, T4 and T5) at three elevations for each site. These soil columns were used to conduct simulation experiments under various water-filled pore space gradients (WFPSs) to investigate the potential N2O flux pattern and elucidate the underlying mechanism. Our results showed that nutrient distribution and N2O flux pattern differed significantly between two zones, with the highest N2O fluxes in the transition zone sites and lacustrine zone sites were found at 75 % and 95 % WFPS, respectively. Soil nutrient loss in lower elevation areas is influenced by prolonged impoundment durations. The higher N2O fluxes in the lacustrine zone can be attributed to increased nutrient levels resulting from anthropogenic activities. Furthermore, correlation analysis revealed that soil bulk density significantly impacted N2O fluxes across all sites, while NO3-and SOC facilitated N2O emissions in T1-T2 and T4-T5, respectively. It was evident that N2O production primarily contributed to nitrification in the transition zone and was constrained by the mineralization process, whereas denitrification dominated in the lacustrine zone. Notably, the annual N2O efflux from WLFZs accounted for 27 % of that from the water-air interface in HJD Reservoir, indicating a considerably lower contribution than anticipated. Nevertheless, this study highlights the significance of WLFZs as a vital potential source of N2O emission, particularly under the influence of anthropogenic activities and high WFPS gradient.

12.
Arch Dermatol Res ; 316(6): 299, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38819446

RESUMEN

Cutaneous squamous cell carcinoma (cSCC) is a malignant tumor originating from epidermal or appendageal keratinocytes, with a rising incidence in recent years. Understanding the molecular mechanism driving its development is crucial. This study aims to investigate whether miR-34a-5p is involved in the pathogenesis of cSCC by targeting Sirtuin 6 (SIRT6).The expression levels of miR-34a-5p and SIRT6 were determined in 15 cSCC tissue specimens, 15 normal tissue specimens and cultured cells via real-time polymerase chain reaction (RT-qPCR). Pearson's correlation analysis was conducted to evaluate the relationship between miR-34a-5p and SIRT6 expression levels in cSCC tissues. A431 and SCL-1 cells were transfected with miR-34a-5p mimic, negative control or miR-34a-5p mimic together with recombinant plasmids containing SIRT6 gene. Cell counting kit-8, clone formation assay, wound healing assay, and flow cytometry were employed to assess the effects of these transfections on proliferation, migration, and apoptosis, respectively. The interaction between miR-34a-5p and SIRT6 was characterized using a dual-luciferase reporter assay.MiR-34a-5p expression was down-regulated in cSCC tissues significantly, while the SIRT6 expression was the opposite. A negative correlation was observed between the expression of miR-34a-5p and SIRT6 in cSCC tissues. Furthermore, overexpression of miR-34a-5p led to a significant reduction in the proliferation and migration abilities of A431 and SCL-1 cells, accompanied by an increase in apoptosis levels and a decrease in SIRT6 expression levels. MiR-34a-5p was identified as a direct target of SIRT6. Importantly, overexpression of SIRT6 effectively counteracted the inhibitory effect mediated by miR-34a-5p in cSCC cells.Our findings suggest that miR-34a-5p functions as a tumor suppressor in cSCC cells by targeting SIRT6.


Asunto(s)
Apoptosis , Carcinoma de Células Escamosas , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , MicroARNs , Sirtuinas , Neoplasias Cutáneas , Humanos , Sirtuinas/genética , Sirtuinas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/metabolismo , Apoptosis/genética , Movimiento Celular/genética , Proliferación Celular/genética , Línea Celular Tumoral , Progresión de la Enfermedad , Masculino , Regulación hacia Abajo , Femenino , Persona de Mediana Edad
13.
Chem Sci ; 15(3): 1046-1050, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38239696

RESUMEN

The strong promotion effects of alkali/alkaline earth metals are frequently reported for heterogeneous catalytic processes such as propane dehydrogenation (PDH), but their functioning principles remain elusive. This paper describes the effect of the addition of calcium (Ca) on reducing the deactivation rate of platinum-tin (Pt-Sn) catalyzed PDH from 0.04 h-1 to 0.0098 h-1 at 873 K under a WHSV of 16.5 h-1 of propane. The Pt-Sn-Ca catalyst shows a high propylene selectivity of >96% with a propylene production rate of 41 molC3H6 (gPt h)-1 and ∼1% activity loss after regeneration. The combination of characterization and DFT simulations reveals that Ca acts as a structural promoter favoring the transition of Snn+ in the parent catalyst to Sn0 during reduction, and the latter is an electron donor that increases the electron density of Pt. This greatly suppresses coke formation from deep dehydrogenation. Moreover, it was found that Ca promotes the formation of a highly reactive and sintering-resistant sub-nano Pt-Sn alloy with a diameter of approximately 0.8 nm. These lead to high activity and selectivity for the Pt-Sn-Ca catalyst for PDH.

14.
Nat Chem ; 16(4): 575-583, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38168925

RESUMEN

In heterogeneous catalysis, the catalytic dehydrogenation reactions of hydrocarbons often exhibit a negative pressure dependence on hydrogen due to the competitive chemisorption of hydrocarbons and hydrogen. However, some catalysts show a positive pressure dependence for propane dehydrogenation, an important reaction for propylene production. Here we show that the positive activity dependence on H2 partial pressure of gallium oxide-based catalysts arises from metastable hydride mediation. Through in situ spectroscopic, kinetic and computational analyses, we demonstrate that under reaction conditions with H2 co-feeding, the dissociative adsorption of H2 on a partially reduced gallium oxide surface produces H atoms chemically bonded to coordinatively unsaturated Ga atoms. These metastable gallium hydride species promote C-H bond activation while inhibiting deep dehydrogenation. We found that the surface coverage of gallium hydride determines the catalytic performance. Accordingly, benefiting from proper H2 co-feeding, the alumina-supported, trace additive-modified gallium oxide catalyst GaOx-Ir-K/Al2O3 exhibited high activity and selectivity at high propane concentrations.

15.
Nat Commun ; 15(1): 4636, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38821951

RESUMEN

The catalytic partial oxidation of methane (POM) presents a promising technology for synthesizing syngas. However, it faces severe over-oxidation over catalyst surface. Attempts to modify metal surfaces by incorporating a secondary metal towards C-H bond activation of CH4 with moderate O* adsorption have remained the subject of intense research yet challenging. Herein, we report that high catalytic performance for POM can be achieved by the regulation of O* occupation in the atomically dispersed (AD) MoNi alloy, with over 95% CH4 conversion and 97% syngas selectivity at 800 °C. The combination of ex-situ/in-situ characterizations, kinetic analysis and DFT (density functional theory) calculations reveal that Mo-Ni dual sites in AD MoNi alloy afford the declined O2 poisoning on Ni sites with rarely weaken CH4 activation for partial oxidation pathway following the combustion reforming reaction (CRR) mechanism. These results underscore the effectiveness of CH4 turnovers by the design of atomically dispersed alloys with tunable O* adsorption.

16.
Clin Nutr ; 43(7): 1675-1682, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38815493

RESUMEN

OBJECTIVE: This study aimed to investigate the potential association between dietary live microbe intake and sarcopenia. METHODS: Data from 5368 participants were gathered from the National Health and Nutrition Examination Survey (NHANES). Dietary information was assessed using a self-report questionnaire. The participants were categorized into low, medium, and high dietary live microbe groups. Sarcopenia was defined according to the National Institutes of Health (NIH) definition (appendicular skeletal muscle mass/body mass index <0.789 for men and <0.512 for women). Multivariate regression analysis and stratified analyses were performed. RESULTS: After adjusting for potential confounding factors, individuals in the high dietary live microbe group exhibited a lower prevalence of sarcopenia compared to those in the low dietary live microbe group. The adjusted odds ratio (with 95% confidence intervals) was 0.63 (0.44-0.89) (p for trend <0.05). Subgroup analyses indicated a potential difference in the impact of dietary live microbe intake on sarcopenia between individuals with and without diabetes (p for interaction = 0.094). CONCLUSION: Higher dietary live microbe intake was associated with a lower risk of sarcopenia.


Asunto(s)
Dieta , Encuestas Nutricionales , Sarcopenia , Humanos , Sarcopenia/epidemiología , Sarcopenia/prevención & control , Masculino , Femenino , Persona de Mediana Edad , Dieta/métodos , Dieta/estadística & datos numéricos , Anciano , Estudios Transversales , Factores de Riesgo , Prevalencia , Adulto , Índice de Masa Corporal
17.
An Bras Dermatol ; 99(4): 535-545, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38548549

RESUMEN

BACKGROUND: Cutaneous squamous cell carcinoma (CSCC) is one of the most common types of skin cancer worldwide. Therefore, the identification of biomarkers associated with CSCC progression could aid in the early detection of high-risk squamous cell carcinoma and the development of novel therapeutic strategies. OBJECTIVE: This study aimed to investigate the expression patterns of silent mating type Information Regulation 2 homolog 6 (SIRT6) in CSCC and its clinical significance. METHODS: The protein expression level of SIRT6 in tissues was detected by immunohistochemistry, and the correlation between SIRT6 expression and clinicopathological parameters in CSCC patients was analyzed. The relative expression of SIRT6 in CSCC cell lineage and tissue specimens was determined by western blotting and PCR. The effect of SIRT6 silencing on cell proliferation was evaluated using cell counting kit 8. Wound healing, transwell method, and flow cytometry were used to investigate the migration, invasion, and cell cycle distribution/apoptosis of CSCC cells after SIRT6 silencing, respectively. Western blot was used to detect the expression of EMT (Epithelial-Mesenchymal Transition), cycle, apoptosis, and other related proteins. RESULTS: The high expression of SIRT6 was correlated with the location of cancer tissue and Broder staging in CSCC patients. Knockdown of SIRT6 inhibited the proliferation, migration, invasion and EMT of CSCC cells, and promoted their apoptosis, with cells blocked in G1 phase. STUDY LIMITATIONS: No animal experiments were conducted to further verify the results. CONCLUSION: Decreased expression of SIRT6 can inhibit the occurrence and development of CSCC.


Asunto(s)
Apoptosis , Carcinoma de Células Escamosas , Proliferación Celular , Sirtuinas , Neoplasias Cutáneas , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/análisis , Western Blotting , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/genética , Ciclo Celular/fisiología , Línea Celular Tumoral , Movimiento Celular , Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Inmunohistoquímica , Sirtuinas/genética , Sirtuinas/metabolismo , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/genética
18.
Science ; 385(6706): 295-300, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39024431

RESUMEN

The industrial catalysts utilized for propane dehydrogenation (PDH) to propylene, an important alternative to petroleum-based cracking processes, either use expensive metals or metal oxides that are environmentally unbenign. We report that a typically less-active oxide, titanium oxide (TiO2), can be combined with earth-abundant metallic nickel (Ni) to form an unconventional Ni@TiOx catalyst for efficient PDH. The catalyst demonstrates a 94% propylene selectivity at 40% propane conversion and superior stability under industrially relevant conditions. Complete encapsulation of Ni nanoparticles was allowed at elevated temperatures (>550°C). A mechanistic study suggested that the defective TiOx overlayer consisting of tetracoordinated Ti sites with oxygen vacancies is catalytically active. Subsurface metallic Ni acts as an electronic promoter to accelerate carbon-hydrogen bond activation and hydrogen (H2) desorption on the TiOx overlayer.

19.
Sci Total Environ ; 931: 172924, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38697550

RESUMEN

The water quality in the drinking water reservoir directly affects people's quality of life and health. When external pollution input is effectively controlled, endogenous release is considered the main cause of water quality deterioration. As the major nitrogen (N) and phosphorus (P) sources in reservoirs, sediment plays a vital role in affecting the water quality. To understand the spatial and temporal variation of N and P in the sediment, this study analyzed the current characteristics and cumulative effects of a semi-humid reservoir, Yuqiao Reservoir, in North China. The N and P concentrations in the reservoir sediment were decreased along the flow direction, while the minimum values were recorded at the central sediment profile. External input and algal deposition were the main factors leading to higher sediment concentrations in the east (Re-E) and west (Re-W) areas of reservoir sediment profiles. According to the long-term datasets, the peaks of both sediment total nitrogen content and deposition rate were observed in the 2010s, which has increased about three times and six times than in the1990s, respectively. Therefore, the increase in phosphorus concentration may be the main reason for eutrophication in water in recent years. The mineralization of organic matter has a significant promoting effect on releasing N and P from sediments, which will intensify eutrophication in water dominated by P and bring huge challenges to water environment management. This study highlights that the current imbalance in N and P inputs into reservoirs and the endogenous P release from sediment will have a significant impact on water quality.

20.
J Hematol Oncol ; 17(1): 23, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38659046

RESUMEN

BACKGROUND: The autologous anti-B-cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T-cell therapy LCAR-B38M has been approved for the treatment of relapsed and refractory multiple myeloma in many countries across the world under the name ciltacabtagene autoleucel. LEGEND-2 was the first-in-human trial of LCAR-B38M and yielded deep and durable therapeutic responses. Here, we reported the outcomes in LEGEND-2 after a minimal 5-year follow-up. METHODS: Participants received an average dose of 0.5 × 106 cells/kg LCAR-B38M in split or single unfractionated infusions after cyclophosphamide-based lymphodepletion therapy. Investigator-assessed response, survival, safety and pharmacokinetics were evaluated. RESULTS: Seventy-four participants enrolled and had a median follow-up of 65.4 months. The 5-year progression-free survival (PFS) and overall survival (OS) rates were 21.0% and 49.1%, with progressive flattening of the survival curves over time. Patients with complete response (CR) had longer PFS and OS, with 5-year rates of 28.4% and 65.7%, respectively. Twelve patients (16.2%) remained relapse-free irrespective of baseline high-risk cytogenetic abnormality and all had normal humoral immunity reconstituted. An ongoing CR closely correlated with several prognostic baseline indices including favorable performance status, immunoglobulin G subtype, and absence of extramedullary disease, as well as a combination cyclophosphamide and fludarabine preconditioning strategy. Sixty-two (83.8%) suffered progressive disease (PD) and/or death; however, 61.1% of PD patients could well respond to subsequent therapies, among which, the proteasome inhibitor-based regimens benefited the most. Concerning the safety, hematologic and hepatic function recovery were not significantly different between non-PD and PD/Death groups. A low rate of second primary malignancy (5.4%) and no severe virus infection were observed. The patients who tested positive for COVID-19 merely presented self-limiting symptoms. In addition, a sustainable CAR T population of one case with persistent remission was delineated, which was enriched with indolently proliferative and lowly cytotoxic CD4/CD8 double-negative functional T lymphocytes. CONCLUSIONS: These data, representing the longest follow-up of BCMA-redirected CAR T-cell therapy to date, demonstrate long-term remission and survival with LCAR-B38M for advanced myeloma. TRIAL REGISTRATION: LEGEND-2 was registered under the trial numbers NCT03090659, ChiCTRONH-17012285.


Asunto(s)
Antígeno de Maduración de Linfocitos B , Inmunoterapia Adoptiva , Mieloma Múltiple , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Antígeno de Maduración de Linfocitos B/inmunología , Estudios de Seguimiento , Inmunoterapia Adoptiva/métodos , Inmunoterapia Adoptiva/efectos adversos , Mieloma Múltiple/terapia , Mieloma Múltiple/mortalidad , Receptores Quiméricos de Antígenos/uso terapéutico , Receptores Quiméricos de Antígenos/inmunología , Inducción de Remisión , Tasa de Supervivencia
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