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1.
Cell ; 159(4): 800-13, 2014 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-25417157

RESUMEN

We sequenced the MSY (male-specific region of the Y chromosome) of the C57BL/6J strain of the laboratory mouse Mus musculus. In contrast to theories that Y chromosomes are heterochromatic and gene poor, the mouse MSY is 99.9% euchromatic and contains about 700 protein-coding genes. Only 2% of the MSY derives from the ancestral autosomes that gave rise to the mammalian sex chromosomes. Instead, all but 45 of the MSY's genes belong to three acquired, massively amplified gene families that have no homologs on primate MSYs but do have acquired, amplified homologs on the mouse X chromosome. The complete mouse MSY sequence brings to light dramatic forces in sex chromosome evolution: lineage-specific convergent acquisition and amplification of X-Y gene families, possibly fueled by antagonism between acquired X-Y homologs. The mouse MSY sequence presents opportunities for experimental studies of a sex-specific chromosome in its entirety, in a genetically tractable model organism.


Asunto(s)
Evolución Biológica , Cromosomas de los Mamíferos , Ratones Endogámicos C57BL/genética , Análisis de Secuencia de ADN , Cromosoma Y , Animales , Centrómero , Cromosomas Artificiales Bacterianos/genética , Femenino , Humanos , Masculino , Filogenia , Primates/genética , Cromosoma X
2.
J Biol Chem ; 299(12): 105388, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37890782

RESUMEN

The main protease of severe acute respiratory syndrome coronavirus 2, Mpro, is a key viral protein essential for viral infection and replication. Mpro has been the target of many pharmacological efforts; however, the host-specific regulation of Mpro protein remains unclear. Here, we report the ubiquitin-proteasome-dependent degradation of Mpro protein in human cells, facilitated by the human E3 ubiquitin ligase ZBTB25. We demonstrate that Mpro has a short half-life that is prolonged via proteasomal inhibition, with its Lys-100 residue serving as a potential ubiquitin acceptor. Using in vitro binding assays, we observed ZBTB25 and Mpro bind to each other in vitro, and using progressive deletional mapping, we further uncovered the required domains for this interaction. Finally, we used an orthologous beta-coronavirus infection model and observed that genetic ablation of ZBTB25 resulted in a more highly infective virus, an effect lost upon reconstitution of ZBTB25 to deleted cells. In conclusion, these data suggest a new mechanism of Mpro protein regulation as well as identify ZBTB25 as an anticoronaviral E3 ubiquitin ligase.


Asunto(s)
Proteasas 3C de Coronavirus , Proteínas de Unión al ADN , SARS-CoV-2 , Humanos , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteínas Nucleares/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación , Proteasas Virales/genética , Proteasas Virales/metabolismo , Proteínas Virales/metabolismo , SARS-CoV-2/fisiología , Proteasas 3C de Coronavirus/metabolismo , COVID-19/virología
3.
BMC Genomics ; 25(1): 288, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38500084

RESUMEN

BACKGROUND: Larch is an important component of northern forests and a major cultivated tree species in restoration of forest cover using improved seed material. In recent years, the continuous low seed production has severely affected the production of improved variety seedlings and natural regeneration. However, research on the reproductive growth of gymnosperms is extremely scarce. RESULTS: In this study, based on differential transcriptome analysis of two asexual reproductive phases, namely high-yield and low-yield, we further screened 5 ERF family genes that may affect the reproductive development of larch. We analyzed their genetic relationships and predicted their physicochemical properties. The expression patterns of these genes were analyzed in different tissues, developmental stages, hormone treatments, and environmental conditions in hybrid larch. CONCLUSION: The results showed that all 5 genes were induced by low temperature and ABA, and their expression patterns in different tissues suggested a suppressive role in the development of female cones in larch. Among them, LkoERF3-like1 and LkoERF071 may be involved in the flowering age pathway. This study enriches the scarce research on reproductive development in gymnosperms and provides a theoretical basis and research direction for regulating the reproductive development of larch in seed orchards.


Asunto(s)
Larix , Filogenia , Reproducción/genética , Bosques , Árboles
4.
Anal Chem ; 96(10): 4048-4056, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38373182

RESUMEN

In this work, we developed an alternative calibration method for measuring N2O5 with an iodide adduct mass spectrometer (I-CIMS). In this calibration method, N2O5 is heated and then quantified based on the decrease in the amount of NO due to its reaction with the pyrolysis product (NO3). This alternative calibration method was compared with the commonly used method utilizing NOx analyzers equipped with a photolytic converter, which gauge NO2 reduction as a result of its reaction with O3 to quantify N2O5. It is notable that the two methodologies demonstrate favorable consistency in terms of calibrating N2O5, with a variance of less than 10 %. The alternative calibration method is a more reliable way to quantify N2O5 with CIMS, considering the instability of the NO2 conversion efficiency of photolytic converters in NOx analyzers and the loss of N2O5 in the sampling line. The effects of O3 and relative humidity (RH) on the sensitivity toward N2O5 were further examined. There was minimal perturbation of N2O5 quantification upon exposure to O3 even at high concentrations. The N2O5 sensitivity exhibited a nonlinear dependence on RH as it initially rose and then fell. Besides I(N2O5)-, the collisional interaction between I(H2O)- and N2O5 also forms I(HNO3)-, which may interfere with the accurate quantification of HNO3. As a consequence of the pronounced dependence on humidity, it is advisable to implement humidity correction procedures when conducting measurements of N2O5.

5.
Small ; : e2311987, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38506566

RESUMEN

Functionalization of pristine graphene by hydrogen and fluorine is well studied, resulting in graphane and fluorographene structures. In contrast, functionalization of pristine graphene with iodine has not been reported. Here, the functionalization of graphene with iodine using photochemical activation is presented, which is thermally reversible at 400 °C. Additional dispersive dominant Raman modes that are probed by resonance Raman spectroscopy are observed. Additionally, iodinated graphene is probed by Kelvin probe force microscopy and by transport measurements showing p-doping surpassing non-covalent iodine doping by charge transfer-complex formation. The emergent Raman modes combined with strong p-doping indicate that iodine functionalization is distinct from simple iodine doping. A reaction mechanism based on these findings is proposed, identifying the large size of iodine atoms as the probable cause governing regiochemically controlled addition due to steric hinderance of reactive sites. The modification of the electronic structure is explained by the confinement of 1D trans-oligoene chains between sp3 -defects. These results demonstrate the uniqueness of iodine reactivity toward graphene and the modification of the electronic structure of iodinated graphene, highlighting its dependence on the spatial arrangement of substituents.

6.
Small ; : e2312218, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38716754

RESUMEN

Room-temperature phosphorescent materials, renowned for their long luminescence lifetimes, have garnered significant attention in the field of optical materials. However, the challenges posed by thermally induced quenching have significantly hindered the advancement of luminescence efficiency and stability. In this study, thermally enhanced phosphorescent carbon nanodots (CND) are developed by incorporating them into fiber matrices. Remarkably, the phosphorescence lifetime of the thermally enhanced CND exhibits a twofold enhancement, increasing from 326 to 753 ms, while the phosphorescence intensity experienced a tenfold enhancement, increasing from 25 to 245 as the temperature increased to 373 K. Rigid fiber matrices can effectively suppress the non-radiative transition rate of triplet excitons, while high temperatures can desorb oxygen adsorbed on the surface of the CND, disrupting the interaction between the CND and oxygen. Consequently, a thermally enhanced phosphorescence is obtained. In addition, benefiting from the thermally enhanced phosphorescence property of CND, a warning indicator with an anti-counterfeiting function for monitoring cold-chain logistics is demonstrated based on CND.

7.
Small ; 20(25): e2309331, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38213019

RESUMEN

The ß-relaxation is one of the major dynamic behaviors in metallic glasses (MGs) and exhibits diverse features. Despite decades of efforts, the understanding of its structural origin and contribution to the overall dynamics of MG systems is still unclear. Here two palladium-based Pd─Cu─P and Pd─Ni─P MGs are reported with distinct different ß-relaxation behaviors and reveal the structural origins for the difference using the advanced X-ray photon correlation spectroscopy and absorption fine structure techniques together with the first-principles calculations. The pronounced ß-relaxation and fast atomic dynamics in the Pd─Cu─P MG mainly come from the strong mobility of Cu atoms and their locally favored structures. In contrast, the motion of Ni atoms is constrained by P atoms in the Pd─Ni─P MG, leading to the weakened ß-relaxation peak and sluggish dynamics. The correlation of atomic dynamics with microscopic structures provides a way to understand the structural origins of different dynamic behaviors as well as the nature of aging in disordered materials.

8.
J Med Virol ; 96(3): e29543, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38528839

RESUMEN

Amidst the COVID-19 pandemic, uncertainty persists among caregivers regarding the vaccination of pediatric liver transplant recipients (PLTRs). This study evaluates the immunogenicity and safety of COVID-19 vaccination in this vulnerable population. A cohort of 30 PLTRs underwent sequential vaccinations with an inactivated SARS-CoV-2 vaccine followed by an Ad5-nCoV booster. We collected and analyzed blood samples pre-vaccination and four weeks post-vaccination to quantify antibody and IGRA (IFN-γ Release Assay) levels. We also documented any adverse reactions occurring within seven days post-vaccination and monitored participants for infections over six months post-vaccination, culminating in a comprehensive statistical analysis. The Ad5-nCoV booster substantially elevated IgG (T1: 18.01, 20%; T2: 66.61, 55%) and nAb (T1: 119.29, 8%; T2: 3799.75, 80%) levels, as well as T-cell responses, in comparison to the initial dose. The first dose was associated with some common adverse reactions, such as injection site pain (13.3%) and fever (16.6%), but a low rate of systemic reactions (16.0%). There was no significant difference in Omicron infection rates or RTPCR conversion times between vaccinated and unvaccinated groups. Notably, following Omicron infection, vaccinated individuals exhibited significantly higher SARS-CoV-2 IgG and nAb titers (average IgG: 231.21 vs. 62.09 S/CO, p = 0.0003; nAb: 5246.11 vs. 2592.07 IU/mL, p = 0.0002). The use of inactivated vaccines followed by an Ad5-nCoV booster in PLTRs is generally safe and elicits a robust humoral response, albeit with limited T-cell responses.


Asunto(s)
COVID-19 , Trasplante de Hígado , Humanos , Niño , Vacunas contra la COVID-19/efectos adversos , COVID-19/prevención & control , Pandemias , SARS-CoV-2 , Anticuerpos Antivirales , Inmunoglobulina G , Vacunas de Productos Inactivados/efectos adversos , Anticuerpos Neutralizantes , Vacunación
9.
Pediatr Res ; 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38678116

RESUMEN

BACKGROUND: Diagnosis of fever of unknown origin remains challenge for pediatricians. Lymphadenopathy is a separate entity that mainly originates from infection or malignancy. METHODS: 168 patients with FUO accompanied by lymphadenectasis were reviewed. 33 lymph node tissue samples were examined by mNGS. Differences in clinical characteristics were compared among different disease groups. The value of mNGS in diagnosing and improving the clinical situation was assessed. RESULTS: Multivariate analysis revealed that hepatosplenomegaly and LDH levels were associated with infectious diseases. Arthralgia was correlated with non-infectious inflammatory diseases. Weight loss and a node located in supraclavicular region may indicate neoplastic diseases. mNGS-positive rate was 60.60%, higher than that obtained with traditional methods. Treatment for 3/4 patients was adjusted according to the pathogen detected by mNGS, and antibiotics uses was discontinued or degraded in over 1/2 of the patients according to mNGS results. CONCLUSIONS: Clinical characteristics of children with lymphadenopathy related to FUO have limited diagnostic value for distinguishing different kinds of diseases, while mNGS of lymph node tissue serves as a useful tool for identifying infectious diseases, especially those caused by rare pathogens. mNGS results can lead to not only adjustments in targeted treatment but also further confirmation of underlying diseases. IMPACT STATEMENT: 1. The clinical features of children with FUO and lymphadenopathy differ according to disease group,although multivariate analysis indicated little diagnostic value for these features. 2. mNGS on lymph node tissue from children with FUO may serve as a efficient tool for distinguishing infectious diseases from other diseases. This is especially useful when a diagnosis cannot be determined with traditional methods. 3. mNGS targeted treatment can be administered in a timely manner and some underlying diseases can be indicated.

10.
Pediatr Res ; 95(3): 843-851, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37857845

RESUMEN

BACKGROUND: Studies on mNGS application in pediatric oncology patients, who are at high risk of infection, are quite limited. METHODS: From March 2020 to June 2022, a total of 224 blood samples from 195 pediatric oncology patients who were suspected as bloodstream infections were enrolled in this study. Their clinical and laboratory data were retrospectively reviewed, and the diagnostic performance of mNGS was assessed. RESULTS: Compared to the reference tests, mNGS showed significantly higher sensitivity (89.8% vs 32.5%, P < 0.001) and clinical agreement (76.3% vs 51.3%, P < 0.001) in detecting potential pathogens and distinguishing BSI from non-BSI. Especially, mNGS had an outstanding performance for virus detection, contributing to 100% clinical diagnosed virus. Samples from patients with neutropenia showed higher incidence of bacterial infections (P = 0.035). The most identified bacteria were Escherichia coli, and the overall infections by gram-negative bacteria were significantly more prevalent than those by gram-positive ones (90% vs 10%, P < 0.001). Overall, mNGS had an impact on the antimicrobial regimens' usage in 54.3% of the samples in this study. CONCLUSIONS: mNGS has the advantage of rapid and effective pathogen diagnosis in pediatric oncology patients with suspected BSI, especially for virus. IMPACT: Compared with reference tests, mNGS showed significantly higher sensitivity and clinical agreement in detecting potential pathogens and distinguishing bloodstream infections (BSI) from non-BSI. mNGS is particularly prominent in clinical diagnosed virus detection. The incidence of bacterial infection was higher in patients with neutropenia, and the overall infection rate of Gram-negative bacteria was significantly higher than that of Gram-positive bacteria. mNGS affects the antimicrobial regimens' usage in more than half of patients.


Asunto(s)
Antiinfecciosos , Neoplasias , Neutropenia , Sepsis , Niño , Humanos , Estudios Retrospectivos , Sepsis/diagnóstico , Secuenciación de Nucleótidos de Alto Rendimiento , Neutropenia/diagnóstico , Escherichia coli , Neoplasias/complicaciones , Neoplasias/diagnóstico , Sensibilidad y Especificidad
11.
BMC Infect Dis ; 24(1): 186, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38347526

RESUMEN

OBJECTIVES: In this study, we describe the patterns of antibiotic prescription for neonates based on World Health Organization's (WHO) Essential Medicines List Access, Watch, and Reserve (AWaRe), and the Management of Antibiotic Classification (MAC) Guidelines in China. METHODS: One-day point-prevalence surveys (PPS) on antimicrobial prescriptions were conducted on behalf of hospitalized neonates in China from September 1 and November 30, annually from 2017 to 2019. RESULTS: Data was collected for a total of 2674 neonatal patients from 15 hospitals in 9 provinces across China of which 1520 were newborns who received at least one antibiotic agent. A total of 1943 antibiotic prescriptions were included in the analysis. The most commonly prescribed antibiotic was meropenem (11.8%). The most common reason for prescribing antibiotic to neonates was pneumonia (44.2%). There were 419 (21.6%), 1343 (69.1%) and 6 (0.3%) antibiotic prescriptions in the Access, Watch and Reserve groups, respectively. According to MAC Guidelines in China, there were 1090 (56.1%) antibiotic agents in the Restricted and 414 (21.3%) in the Special group. CONCLUSION: Broad-spectrum antibiotics included in the Watch and Special groups were likely to be overused in Chinese neonates.


Asunto(s)
Antibacterianos , Prescripciones de Medicamentos , Humanos , Recién Nacido , Prevalencia , Encuestas de Atención de la Salud , Antibacterianos/uso terapéutico , China/epidemiología
12.
J Biochem Mol Toxicol ; 38(3): e23671, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38454809

RESUMEN

Obesity is a major cause of nonalcohol fatty liver disease (NAFLD), which is characterized by hepatic fibrosis, lipotoxicity, inflammation, and apoptosis. Previous studies have shown that an imbalance in the autonomic nervous system is closely related to the pathogenesis of NAFLD. In this study, we investigated the effects of pyridostigmine (PYR), a cholinesterase (AChE) inhibitor, on HFD-induced liver injury and explored the potential mechanisms involving mitochondrial damage and oxidative stress. A murine model of HFD-induced obesity was established using the C57BL/6 mice, and PYR (3 mg/kg/d) or placebo was administered for 20 weeks. PYR reduced the body weight and liver weight of the HFD-fed mice. Additionally, the serum levels of IL-6, TNF-α, cholesterol, and triglyceride were significantly lower in the PYR-treated versus the untreated mice, corresponding to a decrease in hepatic fibrosis, lipid accumulation, and apoptosis in the former. Furthermore, the mitochondrial morphology improved significantly in the PYR-treated group. Consistently, PYR upregulated ATP production and the mRNA level of the mitochondrial dynamic factors OPA1, Drp1 and Fis1, and the mitochondrial unfolded protein response (UPRmt) factors LONP1 and HSP60. Moreover, PYR treatment activated the Keap1/Nrf2 pathway and upregulated HO-1 and NQO-1, which mitigated oxidative injury as indicated by decreased 8-OHDG, MDA and H2 O2 levels, and increased SOD activity. Finally, PYR elevated acetylcholine (ACh) levels by inhibiting AChE, and upregulated the α7nAChR and M3AChR proteins in the HFD-fed mice. PYR alleviated obesity-induced hepatic injury in mice by mitigating mitochondrial damage and oxidative stress via α7nAChR and M3AChR.


Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Enfermedad del Hígado Graso no Alcohólico , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Bromuro de Piridostigmina/farmacología , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/complicaciones , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/metabolismo , Ratones Endogámicos C57BL , Factor 2 Relacionado con NF-E2/metabolismo , Hígado/metabolismo , Estrés Oxidativo , Cirrosis Hepática/metabolismo , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Dieta , Dieta Alta en Grasa/efectos adversos
13.
Artículo en Inglés | MEDLINE | ID: mdl-38662058

RESUMEN

Impaired basic academic skills (e.g., word recognition) are common in children with Attention Deficit Hyperactivity Disorder (ADHD). The underlying neuropsychological and neural correlates of impaired Chinese reading skills in children with ADHD have not been substantially explored. Three hundred and two children with ADHD (all medication-naïve) and 105 healthy controls underwent the Chinese language skill assessment, and 175 also underwent fMRI scans (84 ADHD and 91 controls). Between-group and mediation analyses were applied to explore the interrelationships of the diagnosis of ADHD, cognitive dysfunction, and impaired reading skills. Five ADHD-related brain functional networks, including the default mode network (DMN) and the dorsal attention network (DAN), were built using predefined regions of interest. Voxel-based group-wise comparisons were performed. The ADHD group performed worse than the control group in word-level reading ability tests, with lower scores in Chinese character recognition (CR) and word chains (WS) (all P < 0.05). With full-scale IQ and sustained attention in the mediation model, the direct effect of ADHD status on the CR score became insignificant (P = 0.066). The underlying neural correlates for the orthographic knowledge (OT) and CR differed between the ADHD and the control group. The ADHD group tended to recruit more DMN regions to maintain their reading performance, while the control group seemed to utilize more DAN regions. Children with ADHD generally presented impaired word-level reading skills, which might be caused by impaired sustained attention and lower IQ. According to the brain functional results, we infer that ADHD children might utilize a different strategy to maintain their orthographic knowledge and character recognition performance.

14.
Int J Mol Sci ; 25(6)2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38542332

RESUMEN

Colorectal cancer (CRC), a prevalent malignant tumor of the digestive system, ranks as the third and second in global incidence and mortality, respectively, in 2020, with 1.93 million new cases (≈10% of all cancers). There are 940,000 deaths (≈9.4% of all cancers), and the incidence of CRC in younger patients (under 50 years of age) has become a new trend. The pathogenesis of CRC is primarily attributed to a series of genetic and epigenetic abnormalities within normal colonic epithelial cells, coupled with the reshaping of the tumor microenvironment in the surrounding stroma. This process leads to the transformation of colorectal adenomas into invasive adenocarcinomas. Although genetic changes are known to be the primary driving force in the occurrence and progression of CRC, recent research indicates that epigenetic regulation serves as a crucial molecular marker in cancer, playing a significant role in the pathological and physiological control of interactions between genetics and the environment. This review discusses the current global epidemiology of CRC, its risk factors, and preventive treatment strategies. The current study explores the latest advancements in the epigenetic regulation of CRC, including DNA methylation, histone modifications, and non-coding RNAs (ncRNAs). These developments hold potential as screening tools, prognostic biomarkers, and therapeutic targets for CRC.


Asunto(s)
Neoplasias Colorrectales , Epigénesis Genética , Humanos , Pronóstico , Metilación de ADN/genética , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/genética , Biomarcadores , Microambiente Tumoral/genética
15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(1): 98-103, 2024 Feb.
Artículo en Zh | MEDLINE | ID: mdl-38433638

RESUMEN

Metabolic abnormality in type 2 diabetes mellitus(T2DM)can cause damage to the central nervous system,leading to cognitive decline.Neurofilament light chain protein(NFL),as a blood marker of neuroaxonal injuries,is significantly associated with the onset of cognitive impairment and affected by the renal function.It can participate in the development of cognitive impairment in T2DM through inflammation,blood-brain barrier breakdown,interaction between microglia and neurons,and Tau protein phosphorylation.We reviewed the mechanism of the occurrence and development of NFL-involved cognitive impairment and the correlation between NFL and renal function in T2DM,hoping to provide a basis for early diagnosis and treatment of cognitive impairment in T2DM patients.


Asunto(s)
Disfunción Cognitiva , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Filamentos Intermedios , Disfunción Cognitiva/etiología , Sistema Nervioso Central , Esperanza
16.
Angew Chem Int Ed Engl ; 63(13): e202400196, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38356038

RESUMEN

The development of new chemically recyclable polymers via monomer design would provide a transformative strategy to address the energy crisis and plastic pollution problem. Biaryl-fused cyclic esters were targeted to generate axially chiral polymers, which would impart new material performance. To overcome the non-polymerizability of the biaryl-fused monomer DBO, a cyclic ester Me-DBO installed with dimethyl substitution was prepared to enable its polymerizability via enhancing torsional strain. Impressively, Me-DBO readily went through well-controlled ring-opening polymerization, producing polymer P(Me-DBO) with high glass transition temperature (Tg >100 °C). Intriguingly, mixing these complementary enantiopure polymers containing axial chirality promoted a transformation from amorphous to crystalline material, affording a semicrystalline stereocomplex with a melting transition temperature more than 300 °C. P(Me-DBO) were capable of depolymerizing back to Me-DBO in high efficiency, highlighting an excellent recyclability.

17.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(2): 131-138, 2024 Feb 15.
Artículo en Zh | MEDLINE | ID: mdl-38436309

RESUMEN

OBJECTIVES: To investigate the clinical characteristics and prognosis of pneumococcal meningitis (PM), and drug sensitivity of Streptococcus pneumoniae (SP) isolates in Chinese children. METHODS: A retrospective analysis was conducted on clinical information, laboratory data, and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country. RESULTS: Among the 160 children with PM, there were 103 males and 57 females. The age ranged from 15 days to 15 years, with 109 cases (68.1%) aged 3 months to under 3 years. SP strains were isolated from 95 cases (59.4%) in cerebrospinal fluid cultures and from 57 cases (35.6%) in blood cultures. The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87) and 27% (21/78), respectively. Fifty-five cases (34.4%) had one or more risk factors for purulent meningitis, 113 cases (70.6%) had one or more extra-cranial infectious foci, and 18 cases (11.3%) had underlying diseases. The most common clinical symptoms were fever (147 cases, 91.9%), followed by lethargy (98 cases, 61.3%) and vomiting (61 cases, 38.1%). Sixty-nine cases (43.1%) experienced intracranial complications during hospitalization, with subdural effusion and/or empyema being the most common complication [43 cases (26.9%)], followed by hydrocephalus in 24 cases (15.0%), brain abscess in 23 cases (14.4%), and cerebral hemorrhage in 8 cases (5.0%). Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old, with rates of 91% (39/43) and 83% (20/24), respectively. SP strains exhibited complete sensitivity to vancomycin (100%, 75/75), linezolid (100%, 56/56), and meropenem (100%, 6/6). High sensitivity rates were also observed for levofloxacin (81%, 22/27), moxifloxacin (82%, 14/17), rifampicin (96%, 25/26), and chloramphenicol (91%, 21/23). However, low sensitivity rates were found for penicillin (16%, 11/68) and clindamycin (6%, 1/17), and SP strains were completely resistant to erythromycin (100%, 31/31). The rates of discharge with cure and improvement were 22.5% (36/160) and 66.2% (106/160), respectively, while 18 cases (11.3%) had adverse outcomes. CONCLUSIONS: Pediatric PM is more common in children aged 3 months to under 3 years. Intracranial complications are more frequently observed in children under 1 year old. Fever is the most common clinical manifestation of PM, and subdural effusion/emphysema and hydrocephalus are the most frequent complications. Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates. Adverse outcomes can be noted in more than 10% of PM cases. SP strains are high sensitivity to vancomycin, linezolid, meropenem, levofloxacin, moxifloxacin, rifampicin, and chloramphenicol.


Asunto(s)
Empiema , Hidrocefalia , Meningitis Neumocócica , Efusión Subdural , Lactante , Femenino , Masculino , Humanos , Niño , Recién Nacido , Adolescente , Meningitis Neumocócica/tratamiento farmacológico , Meningitis Neumocócica/epidemiología , Meropenem , Vancomicina , Levofloxacino , Linezolid , Moxifloxacino , Estudios Retrospectivos , Rifampin , Streptococcus pneumoniae , Cloranfenicol
18.
Apoptosis ; 28(3-4): 458-470, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36520320

RESUMEN

The normal colorectal mucosa undergoes precancerous lesions that can develop over time into colorectal cancer (CRC). In the stage of precancerous lesions, DNA replication stress may lead to genome instability. We have performed whole-exome sequencing on genomic DNA obtained from three cases of CRC tissues and identified a novel frameshift mutation of DNA damage inducible 1 homolog 2 gene (DDI2, c. 854 del T). To date, there is no direct evidence that DDI2 is involved in the carcinogenesis of CRC. In this study, we demonstrated that DDI2 is upregulated in the early stage of CRC based on clinical samples and public databases. We also found that 5FU, a standard chemotherapeutic agent for CRC treatment, increased DDI2 mRNA levels in a dose-dependent manner. Depression of DDI2 inhibited CRC cell proliferation, migration and invasion both in vitro and in vivo. Transcriptome sequencing revealed that DDI2 was involved in the mitogen-activated protein kinase (MAPK) pathway. Furthermore, DDI2 resists a MAPK kinase (MEK) inhibitor (trametinib) and a PolyADP-ribose polymerase 1 (PARP1) inhibitor (talazoparib) induced apoptosis in CRC cells. Thus, our results indicate that DDI2 may play a vital role in the carcinogenesis of CRC and could serve as a promising therapeutic target for CRC.


Asunto(s)
Antineoplásicos , Neoplasias Colorrectales , Humanos , Antineoplásicos/farmacología , Apoptosis , Carcinogénesis/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Regulación Neoplásica de la Expresión Génica
19.
Small ; 19(31): e2302504, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37282771

RESUMEN

Phosphorescent materials as block elements to build artwork incorporating the time and emission, enable them with spectacular lighting effects. In this work, enhanced phosphorescence of carbon nanodots (CNDs) is demonstrated via double confinement strategy, which silica and epoxy resin are used as the first and the second order confinement layer. The multi-confined CNDs show an enhanced phosphorescence quantum yield up to 16.4%, with enduring emission lifetime up to 1.44 s. Delicately, the plasticity of the epoxy resin enables them easily to be designed for 3D artworks with long emission lifetimes in different shapes. The efficient and eco-friendly phosphorescent CNDs may arouse intense interest both in the academic community and markets.

20.
J Transl Med ; 21(1): 697, 2023 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-37803341

RESUMEN

BACKGROUND: Periodontitis is considered as a risk factor for cardiovascular diseases and atherosclerosis. However, the relationship between periodontitis and stroke is rarely studied. Therefore, we aimed to explore the relationship between periodontitis and stroke. METHODS: Statistical analysis was performed using the complex sampling design. We analyzed data on 6,460 participants, representing 92,856,028 American citizens aged 30 years or older, who had valid data on periodontitis and stroke from the National Health and Nutrition Examination Survey 2009-2014. We used clinical attachment level and probing pocket depth precisely to determine periodontitis and it is the first time to use such a precise method for exploring the relationship between periodontitis and stroke. RESULTS: 39.9% of participants had periodontitis and 2.1% of participants had a record of stroke diagnosis. Stroke was associated with severity levels of periodontitis (p for trend = 0.018). The odds ratio for stroke was significantly elevated in the severe periodontitis and moderate periodontitis participants compared to participants without periodontitis (OR for severe periodontitis: 2.55, 95% CI 1.25-5.21; OR for moderate periodontitis: 1.71, 95% CI 1.17-2.50). After adjusting for race/ethnicity and sex, the association remained significant (p for trend = 0.009). After further adjusting for BMI, hypercholesterolemia, diabetes, alcohol consumption and physical activity, the association still existed (p for trend = 0.027). The association was significant consistently after further adjusting for age (p for trend = 0.033). CONCLUSIONS: In this nationally representative study, we found an association between periodontitis and stroke. The risk of stroke in participants with severe periodontitis and moderate periodontitis was 2.55 times and 1.71times as high as those without periodontitis. Dental health management may be of benefit to stroke prevention.


Asunto(s)
Diabetes Mellitus , Periodontitis , Accidente Cerebrovascular , Humanos , Encuestas Nutricionales , Periodontitis/complicaciones , Periodontitis/epidemiología , Factores de Riesgo , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/epidemiología
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