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1.
Virol J ; 21(1): 216, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39272111

RESUMO

BACKGROUND: Enterovirus A71 (EV-A71), as a neurotropic virus, mainly affects infants and young children under the age of 5. EV-A71 infection causes hand-foot-mouth disease and herpetic angina, and even life-threatening neurological complications. However, the molecular mechanism by which EV-A71 induces nervous system damage remains elusive. The viral protease 3C plays an important role during EV-A71 infection and is also a key intersection of virus-host interactions. Previously, we used yeast two-hybrid to screen out the host protein Double-stranded RNA-binding protein Staufen homolog 2 (Stau2), an important member involved in neuronal mRNA transport, potentially interacts with 3C. METHODS: We used coimmunoprecipitation (Co-IP) and immunofluorescence assay (IFA) to confirm that EV-A71 3C interacts with Stau2. By constructing the mutant of Stau2, we found the specific site where the 3C protease cleaves Stau2. Detection of VP1 protein using Western blotting characterized EV-A71 viral replication, and overexpression or knockdown of Stau2 exhibited effects on EV-A71 replication. The effect of different cleavage products on EV-A71 replication was demonstrated by constructing Stau2 truncates. RESULTS: In this study, we found that EV-A71 3C interacts with Stau2. Stau2 is cleaved by 3C at the Q507-G508 site. Overexpression of Stau2 promotes EV-A71 VP1 protein expression, whereas depletion of Stau2 by small interfering RNA inhibits EV-A71 replication. Stau2 is essential for EV-A71 replication, and the product of Stau2 cleavage by 3C, 508-570 aa, has activity that promotes EV-A71 replication. In addition, we found that mouse Stau2 is also cleaved by EV-A71 3C at the same site. CONCLUSIONS: Our research provides an example for EV-A71-host interaction, enriching key targets of host factors that contribute to viral replication.


Assuntos
Proteases Virais 3C , Enterovirus Humano A , Proteínas de Ligação a RNA , Proteínas Virais , Replicação Viral , Humanos , Enterovirus Humano A/fisiologia , Enterovirus Humano A/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteases Virais 3C/metabolismo , Proteínas Virais/metabolismo , Proteínas Virais/genética , Cisteína Endopeptidases/metabolismo , Cisteína Endopeptidases/genética , Interações Hospedeiro-Patógeno , Imunoprecipitação , Infecções por Enterovirus/virologia , Infecções por Enterovirus/metabolismo , Células HEK293 , Ligação Proteica , Proteínas do Tecido Nervoso
2.
Physiol Plant ; 176(4): e14444, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39005134

RESUMO

Bamboo, renowned as the fastest-growing plant globally, matures within an astonishingly short period of 40-50 days from shoots, reaching heights of 10-20 meters. Moreover, it can be harvested for various uses within 3-5 years. Bamboo exhibits exceptional mechanical properties, characterized by high hardness and flexibility, largely attributed to its lignin content. Phenylalanine ammonia-lyase (PAL) catalyzes the crucial initial step in lignin biosynthesis, but its precise role in bamboo lignification processes remains elusive. Thus, elucidating the functions of PAL genes in bamboo lignification processes is imperative for understanding its rapid growth and mechanical strength. Here, we systematically identified and classified PAL genes in Moso bamboo, ensuring nomenclature consistency across prior studies. Subsequently, we evaluated PAL gene expression profiles using publicly available transcriptome data. The downregulation of PePALs expression in Moso bamboo through in planta gene editing resulted in a decrease in PAL activity and a subsequent reduction in lignin content. In contrast, overexpression of PePAL led to enhanced PAL activity and an increase in lignin content. These findings highlight the critical role of PAL in the lignin biosynthesis process of Moso bamboo, which will help to unravel the mechanism underpinning bamboo's rapid growth and mechanical strength, with a specific emphasis on elucidating the functions of PAL genes.


Assuntos
Regulação da Expressão Gênica de Plantas , Lignina , Fenilalanina Amônia-Liase , Fenilalanina Amônia-Liase/genética , Fenilalanina Amônia-Liase/metabolismo , Lignina/biossíntese , Lignina/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sasa/genética , Sasa/metabolismo , Sasa/enzimologia
3.
Environ Sci Technol ; 58(14): 6258-6273, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38450439

RESUMO

Contamination of small-sized plastics is recognized as a factor of global change. Nanoplastics (NPs) can readily enter organisms and pose significant ecological risks. Arbuscular mycorrhizal (AM) fungi are the most ubiquitous and impactful plant symbiotic fungi, regulating essential ecological functions. Here, we first found that an AM fungus, Rhizophagus irregularis, increased lettuce shoot biomass by 25-100% when exposed to positively and negatively charged NPs vs control, although it did not increase that grown without NPs. The stress alleviation was attributed to the upregulation of gene expressions involving phytohormone signaling, cell wall metabolism, and oxidant scavenging. Using a root organ-fungus axenic growth system treated with fluorescence-labeled NPs, we subsequently revealed that the hyphae captured NPs and further delivered them to roots. NPs were observed at the hyphal cell walls, membranes, and spore walls. NPs mediated by the hyphae were localized at the root epidermis, cortex, and stele. Hyphal exudates aggregated positively charged NPs, thereby reducing their uptake due to NP aggregate formation (up to 5000 nm). This work demonstrates the critical roles of AM fungus in regulating NP behaviors and provides a potential strategy for NP risk mitigation in terrestrial ecosystems. Consequent NP-induced ecological impacts due to the affected AM fungi require further attention.


Assuntos
Micorrizas , Micorrizas/metabolismo , Microplásticos , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Hifas , Ecossistema , Expressão Gênica
4.
J Periodontal Res ; 59(2): 299-310, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38014515

RESUMO

BACKGROUND: Numerous studies have proposed that periodontitis is a potential risk factor for Alzheimer's disease. However, the association between periodontitis and brain normal cognition in aged and elderly individuals (NCs) is unclear. Such a link could provide clues to Alzheimer's disease development and strategies for early prevention. OBJECTIVE: To explore the associations between periodontal condition and metrics of both brain structure and function among NCs with the help of multimodal magnetic resonance imaging (MRI). METHODS: High-resolution T1-weighted structural data, resting-state functional-MRI data, and measures of periodontal condition were collected from 40 NCs. Cortical volume, thickness, and area as well as regional homogeneity were calculated with the aid of DPABISurf software. Correlation analyses were then conducted between each imaging metric and periodontal index. RESULTS: Consistent negative correlations were observed between severity of periodontitis (mild, moderate, severe) and cortical volume, area, and thickness, not only in brain regions that took charge of primary function but also in brain regions associated with advanced cognition behavior. Among participants with mild attachment loss (AL) and a shallow periodontal pocket depth (PPD), periodontal index was positively correlated with most measures of brain structure and function, while among participants with severe AL and deep PPD, periodontal index was negatively correlated with measures of brain structure and function (all p < .005 for each hemisphere). CONCLUSIONS: Our results demonstrate that periodontitis is associated with widespread changes in brain structure and function among middle-aged and elderly adults without signs of cognitive decline, which might be a potential risk factor for brain damage.


Assuntos
Doença de Alzheimer , Doenças Periodontais , Periodontite , Idoso , Adulto , Pessoa de Meia-Idade , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Periodontite/complicações , Periodontite/diagnóstico por imagem , Periodontite/patologia , Cognição , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Doenças Periodontais/patologia
5.
J Nanobiotechnology ; 22(1): 359, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907216

RESUMO

Periodontitis is a chronic inflammation caused by a bacterial infection and is intimately associated with an overactive immune response. Biomaterials are being utilized more frequently in periodontal therapy due to their designability and unique drug delivery system. However, local and systemic immune response reactions driven by the implantation of biomaterials could result in inflammation, tissue damage, and fibrosis, which could end up with the failure of the implantation. Therefore, immunological adjustment of biomaterials through precise design can reduce the host reaction while eliminating the periodontal tissue's long-term chronic inflammation response. It is important to note that macrophages are an active immune system component that can participate in the progression of periodontal disease through intricate polarization mechanisms. And modulating macrophage polarization by designing biomaterials has emerged as a new periodontal therapy technique. In this review, we discuss the role of macrophages in periodontitis and typical strategies for polarizing macrophages with biomaterials. Subsequently, we discuss the challenges and potential opportunities of using biomaterials to manipulate periodontal macrophages to facilitate periodontal regeneration.


Assuntos
Materiais Biocompatíveis , Imunoterapia , Macrófagos , Periodontite , Humanos , Periodontite/tratamento farmacológico , Periodontite/terapia , Materiais Biocompatíveis/química , Macrófagos/imunologia , Macrófagos/efeitos dos fármacos , Animais , Imunoterapia/métodos , Sistemas de Liberação de Medicamentos/métodos
6.
J Nanobiotechnology ; 22(1): 466, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095867

RESUMO

BACKGROUND: Osteoarthritis (OA) is a degenerative joint disease characterized by the progressive degeneration of articular cartilage, leading to pain, stiffness, and loss of joint function. The pathogenesis of OA involves multiple factors, including increased intracellular reactive oxygen species (ROS), enhanced chondrocyte apoptosis, and disturbances in cartilage matrix metabolism. These processes contribute to the breakdown of the extracellular matrix (ECM) and the loss of cartilage integrity, ultimately resulting in joint damage and dysfunction. RNA interference (RNAi) therapy has emerged as a promising approach for the treatment of various diseases, including hATTR and acute hepatic porphyria. By harnessing the natural cellular machinery for gene silencing, RNAi allows for the specific inhibition of target genes involved in disease pathogenesis. In the context of OA, targeting key molecules such as matrix metalloproteinase-13 (MMP13), which plays a critical role in cartilage degradation, holds great therapeutic potential. RESULTS: In this study, we developed an innovative therapeutic approach for OA using a combination of liposome-encapsulated siMMP13 and NG-Monomethyl-L-arginine Acetate (L-NMMA) to form an injectable hydrogel. The hydrogel served as a delivery vehicle for the siMMP13, allowing for sustained release and targeted delivery to the affected joint. Experiments conducted on destabilization of the medial meniscus (DMM) model mice demonstrated the therapeutic efficacy of this composite hydrogel. Treatment with the hydrogel significantly inhibited the degradation of cartilage matrix, as evidenced by histological analysis showing preserved cartilage structure and reduced loss of proteoglycans. Moreover, the hydrogel effectively suppressed intracellular ROS accumulation in chondrocytes, indicating its anti-oxidative properties. Furthermore, it attenuated chondrocyte apoptosis, as demonstrated by decreased levels of apoptotic markers. CONCLUSION: In summary, the injectable hydrogel containing siMMP13, endowed with anti-ROS and anti-apoptotic properties, may represent an effective therapeutic strategy for osteoarthritis in the future.


Assuntos
Apoptose , Condrócitos , Hidrogéis , Metaloproteinase 13 da Matriz , Osteoartrite , Espécies Reativas de Oxigênio , Animais , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Osteoartrite/patologia , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Hidrogéis/química , Metaloproteinase 13 da Matriz/metabolismo , Camundongos , Condrócitos/metabolismo , Condrócitos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Masculino , Cartilagem Articular/metabolismo , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/patologia , Lipossomos/química , Humanos
7.
J Nanobiotechnology ; 22(1): 678, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-39501279

RESUMO

BACKGROUND: The production of ß-lactamases is the most prevalent resistance mechanism for ß-lactam antibiotics in Gram-negative bacteria. Presently, over 4900 ß-lactamases have been discovered, and they are categorized into hundreds of families. In each enzyme family, amino acid substitutions result in subtle changes to enzyme hydrolysis profiles; in contrast, certain conserved sequences retained by all of the family members can serve as important markers for enzyme family identification. RESULTS: The SHV family was chosen as the study object. First, a unique 10-mer peptide was identified as SHV family's epitope by an approach of protein fingerprint analysis. Then, an SHV-specific magnetic epitope-imprinted gel polymer (MEI-GP) was prepared by an epitope surface imprinting technique, and its sorption behavior and recognition mechanism for template epitope and SHV were both elaborated. Finally, the MEI-GP was successfully applied to selectively extract SHV from bacteria, and the extracted SHV was submitted to MALDI-TOF MS for specific determination. By following this strategy, other ß-lactamase families can also be specifically detected. According to the molecular weight displayed in mass spectra, the kind of ß-lactamase and its associated hydrolysis profile on ß-lactams can be easily identified. Based on this, an initial drug option scheme can be quickly formulated for antimicrobial therapy. From protein extraction to medication guidance reporting, the mean time to detection (MTTD) was less than 2 h, which is much faster than conventional phenotype-based methods (at least 16-20 h) and gene-based techniques (usually about 8 h). CONCLUSIONS: This enzyme-specific detection strategy combined the specificity of epitope imprinting with the sensitivity of mass spectrometry, enabling ß-lactamase to be selectively extracted from bacteria and clearly presented in mass spectra. Compared with other drug resistance detection methods, this technique has good specificity, high sensitivity (≤ 15 mg of bacteria), a short MTTD (less than 2 h), and simple operation, and therefore has a broad application prospect in clinical medicine.


Assuntos
Epitopos , Microesferas , beta-Lactamases , beta-Lactamases/química , beta-Lactamases/metabolismo , Epitopos/química , Farmacorresistência Bacteriana , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Impressão Molecular/métodos , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias , Polímeros/química
8.
J Nanobiotechnology ; 22(1): 368, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918787

RESUMO

Active artificial bone substitutes are crucial in bone repair and reconstruction. Calcium phosphate bone cement (CPC) is known for its biocompatibility, degradability, and ability to fill various shaped bone defects. However, its low osteoinductive capacity limits bone regeneration applications. Effectively integrating osteoinductive magnesium ions with CPC remains a challenge. Herein, we developed magnesium malate-modified CPC (MCPC). Incorporating 5% magnesium malate significantly enhances the compressive strength of CPC to (6.18 ± 0.49) MPa, reduces setting time and improves disintegration resistance. In vitro, MCPC steadily releases magnesium ions, promoting the proliferation of MC3T3-E1 cells without causing significant apoptosis, proving its biocompatibility. Molecularly, magnesium malate prompts macrophages to release prostaglandin E2 (PGE2) and synergistically stimulates dorsal root ganglion (DRG) neurons to synthesize and release calcitonin gene-related peptide (CGRP). The CGRP released by DRG neurons enhances the expression of the key osteogenic transcription factor Runt-related transcription factor-2 (RUNX2) in MC3T3-E1 cells, promoting osteogenesis. In vivo experiments using minipig vertebral bone defect model showed MCPC significantly increases the bone volume fraction, bone density, new bone formation, and proportion of mature bone in the defect area compared to CPC. Additionally, MCPC group exhibited significantly higher levels of osteogenesis and angiogenesis markers compared to CPC group, with no inflammation or necrosis observed in the hearts, livers, or kidneys, indicating its good biocompatibility. In conclusion, MCPC participates in the repair of bone defects in the complex post-fracture microenvironment through interactions among macrophages, DRG neurons, and osteoblasts. This demonstrates its significant potential for clinical application in bone defect repair.


Assuntos
Cimentos Ósseos , Peptídeo Relacionado com Gene de Calcitonina , Fosfatos de Cálcio , Osteogênese , Porco Miniatura , Animais , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Cimentos Ósseos/farmacologia , Cimentos Ósseos/química , Camundongos , Suínos , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Osteogênese/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Coluna Vertebral/cirurgia , Gânglios Espinais/metabolismo , Gânglios Espinais/efeitos dos fármacos , Linhagem Celular , Magnésio/farmacologia , Magnésio/química
9.
Med Sci Monit ; 30: e944916, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39233395

RESUMO

BACKGROUND This study aimed to compare the hemodynamic changes and the occurrence of oropharyngeal complications among patients undergoing tracheal intubation with an ordinary laryngoscope, video laryngoscope, and rigid video laryngoscope under general anesthesia. MATERIAL AND METHODS Patients undergoing elective tracheal intubation under general anesthesia were prospectively enrolled as study subjects. Hemodynamic indicators such as diastolic blood pressure (DBP), systolic blood pressure (SBP), mean arterial pressure (MAP), and heart rate (HR), as well as the incidences of oropharyngeal complications, including dental injury, oral mucosal injury, hoarseness, sore throat, and dysphagia, were observed in the patients of 3 groups (group A: ordinary laryngoscope, group B: video laryngoscope, group C: rigid video laryngoscope). Observations were made after anesthesia induction (T0), immediately after tracheal intubation (T1), and at 5 min after intubation (T2). RESULTS The HR at T1 in group A was significantly higher than in groups B and C (P<0.05). However, the difference in the number of tracheal intubations was statistically significant among the 3 groups (P<0.05); group C exhibited the highest first-time success rate of tracheal intubation (95%), whereas group A had the highest failure rate (5%). Significant differences were also noted in the incidences of oral mucosal injury and sore throat among the groups (P<0.05), with the highest incidence in group A and the lowest in group C. CONCLUSIONS Compared with the ordinary laryngoscope, tracheal intubation using a video or rigid video laryngoscope results in milder hemodynamic impacts and fewer intubation-related complications. The rigid video laryngoscope may be safer and more effective.


Assuntos
Anestesia Geral , Frequência Cardíaca , Hemodinâmica , Intubação Intratraqueal , Laringoscópios , Laringoscopia , Humanos , Intubação Intratraqueal/efeitos adversos , Intubação Intratraqueal/métodos , Laringoscópios/efeitos adversos , Anestesia Geral/efeitos adversos , Anestesia Geral/métodos , Masculino , Feminino , Hemodinâmica/fisiologia , Pessoa de Meia-Idade , Adulto , Frequência Cardíaca/fisiologia , Laringoscopia/métodos , Laringoscopia/efeitos adversos , Orofaringe , Pressão Sanguínea/fisiologia , Estudos Prospectivos , Gravação em Vídeo/métodos , Idoso , Faringite/etiologia , Faringite/fisiopatologia
10.
BMC Public Health ; 24(1): 1235, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704531

RESUMO

BACKGROUND: Periodontitis represents the foremost oral condition in young men, strongly correlated with socioeconomic elements and oral health behaviors. This research aimed to assess the prevalence of periodontitis and associated associations with socio-demographics and oral health practices for subsequent Hazard Ratio (HR) estimation. METHODS: A total of 46,476 young men were recruited to the study between August 2022 and October 2023. A questionnaire on socio-demographic factors and oral health-related behaviors related to periodontitis was completed. The standard procedure was used for oral examination. Logistic regression and hazard ratios were used to estimate the influencing factors, whereas the nomogram was used to predict the risk of periodontitis in young men. RESULTS: A total of 46,476 young men were surveyed and completed the questionnaire. The overall prevalence of periodontitis among young men was 1.74%. Out of these, 1.7% had mild periodontitis and 0.6% had moderate periodontitis. Age and dental calculus were important factors in the periodontal health of young men. This nomogram, which includes 7 easily obtainable clinical characteristics routinely collected during periodontitis risk assessment, provides clinicians with a user-friendly tool to assess the risk of periodontal disease in young men. CONCLUSIONS: Regular dental prophylaxis is crucial for young men to maintain their gingival health and prevent the onset of periodontitis. Dental calculus plays a prominent role in this matter, as it serves as a significant contributing factor.


Assuntos
Periodontite , Humanos , Masculino , Periodontite/epidemiologia , Estudos Transversais , China/epidemiologia , Adulto Jovem , Prevalência , Adulto , Fatores de Risco , Inquéritos e Questionários , Adolescente , Nomogramas , Saúde Bucal/estatística & dados numéricos , Fatores Socioeconômicos
11.
BMC Public Health ; 24(1): 2995, 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39472841

RESUMO

BACKGROUND: Dental filling is a prevalent method for treating dental defects. This study aimed to investigate the knowledge, attitude, and practice (KAP) toward dental defects and dental fillings among dental patients in Jinan, Shandong Province, China. METHODS: This cross-sectional study was conducted at the main campus and several branch campuses of Jinan Stomatological Hospital, and community locations within Jinan city between October 2023, and January 2024. Spearman correlation analysis and mediation analysis were used to assess the associations and interrelationships between KAP scores. RESULTS: In this study, 2529 dental patients participated, with 69.1% being females. Of these, 1711 had no dental defects, 551 had defects and fillings, and 267 had defects without fillings. Their median knowledge, attitude, and practice (Questions 1-6) scores were 8.00 [5.00, 12.00] (possible range: 0-18), 27.00 [26.00, 29.00] (possible range: 10-50), and 19.00 [15.00, 24.00] (possible range: 9-45), respectively. Mediation analysis revealed that in patients without dental defects, knowledge had a direct effect on attitude (ß = -0.983, 95% CI: -0.999, -0.966, P < 0.001). Additionally, attitude had a direct effect on practice (ß = -0.797, 95% CI: -1.490, -0.103, P = 0.024), while knowledge had an indirect effect on practice through attitude (ß = 0.783, 95% CI: 0.096, 1.470, P = 0.026). In patients with dental defects who had undergone dental fillings, significant direct effects were observed between knowledge and attitude (ß = -0.736, 95% CI: -0.821, -0.650, P < 0.001), knowledge and practice (ß = 0.396, 95% CI: 0.214, 0.577, P < 0.001), and attitude and practice (ß = -0.499, 95% CI: -0.683, -0.315, P < 0.001). Moreover, knowledge had an indirect effect on practice (ß = 0.367, 95 CI: 0.221, 0.513, P < 0.001). In patients with dental defects but without any fillings, direct effects were found between knowledge and attitude (ß = -0.929, 95% CI: -1.028, -0.829, P < 0.001). CONCLUSIONS: Dental patients had inadequate knowledge, attitude, and practices concerning dental defects and fillings. It is recommended that clinical interventions should focus on enhancing patient education and promoting positive engagement in dental care practices.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Humanos , China/epidemiologia , Feminino , Masculino , Estudos Transversais , Adulto , Pessoa de Meia-Idade , Restauração Dentária Permanente/estatística & dados numéricos , Adulto Jovem , Inquéritos e Questionários , Adolescente , Idoso
12.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33558418

RESUMO

The expansion of anatomically modern humans (AMHs) from Africa around 65,000 to 45,000 y ago (ca. 65 to 45 ka) led to the establishment of present-day non-African populations. Some paleoanthropologists have argued that fossil discoveries from Huanglong, Zhiren, Luna, and Fuyan caves in southern China indicate one or more prior dispersals, perhaps as early as ca. 120 ka. We investigated the age of the human remains from three of these localities and two additional early AMH sites (Yangjiapo and Sanyou caves, Hubei) by combining ancient DNA (aDNA) analysis with a multimethod geological dating strategy. Although U-Th dating of capping flowstones suggested they lie within the range ca. 168 to 70 ka, analyses of aDNA and direct AMS 14C dating on human teeth from Fuyan and Yangjiapo caves showed they derive from the Holocene. OSL dating of sediments and AMS 14C analysis of mammal teeth and charcoal also demonstrated major discrepancies from the flowstone ages; the difference between them being an order of magnitude or more at most of these localities. Our work highlights the surprisingly complex depositional history recorded at these subtropical caves which involved one or more episodes of erosion and redeposition or intrusion as recently as the late Holocene. In light of our findings, the first appearance datum for AMHs in southern China should probably lie within the timeframe set by molecular data of ca. 50 to 45 ka.


Assuntos
Arqueologia , Cavernas/química , DNA Antigo/análise , Fósseis , Sedimentos Geológicos/análise , Migração Humana/história , Datação Radiométrica/métodos , China , História Antiga , Humanos
13.
Altern Ther Health Med ; 30(1): 167-171, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37773669

RESUMO

Background: Rett syndrome (RTT) is now widely recognized as a profound neurological disorder that predominantly affects females and is closely associated with mutations in the methylated CpG binding protein 2 (MECP2) gene located on the X chromosome. The Characteristic symptoms of RTT include the loss of acquired language and motor skills, repetitive hand movements, irregular breathing, and seizures. Additionally, RTT patients may experience sporadic episodes of gastrointestinal problems, hypoplasia, early-onset osteoporosis, bruxism, and screaming episodes. It is worth noting that males exhibit a unique and variable phenotype, though rare in RTT cases, often accompanied by severe manifestations. Case Presentation: In this report, we present the case of a young male child with a de novo c.806delG hemizygous mutation, leading to an atypical presentation of RTT that remarkably mirrors the clinical features of Bartter syndrome, a genetic metabolic disorder. The clinical manifestations in this case included the loss of previously acquired language and motor skills, repetitive hand movements, breathing irregularities, seizures, sporadic episodes of gastrointestinal distress, hypoplasia, early-onset osteoporosis, bruxism, and episodes of screaming. This distinctive presentation underscores the complex diagnostic landscape of RTT, particularly in males, and highlights the need for vigilant clinical evaluation. Conclusions: This case report sheds light on an unusual and atypical presentation of RTT in a young male child with a de novo c.806delG hemizygous mutation. The resemblance of clinical features to Bartter syndrome underscores the diagnostic challenges posed by RTT and highlights the importance of comprehensive clinical assessment and genetic testing, especially in cases deviating from the typical RTT phenotype. Our findings contribute valuable insights into the early diagnosis and management of atypical RTT presentations.


Assuntos
Alcalose , Síndrome de Bartter , Bruxismo , Osteoporose , Síndrome de Rett , Criança , Feminino , Humanos , Masculino , Síndrome de Rett/complicações , Síndrome de Rett/diagnóstico , Síndrome de Rett/genética , Proteína 2 de Ligação a Metil-CpG/genética , Hipóxia , Convulsões
14.
J Environ Manage ; 366: 121807, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39025011

RESUMO

The removal of various pollutants from water is necessary due to the increasing requirements for the removal of various pollutants from wastewater and the quality of drinking water. Polymer microspheres are regarded as exemplary adsorbent materials due to their high adsorption efficiency, excellent adsorption performance, and ease of handling. Herein, the advantages and disadvantages of different preparation methods, modifications, applications and the current research status of polymer microspheres are summarized at large. Furthermore, the enhanced performance of modified composite microspheres is emphasized, including adsorption efficiency, thermal stability, and significant improvements in physical and chemical properties. Subsequently, the current applications and potential of polymeric microspheres for wastewater treatment, including the removal of inorganic and organic pollutants, heavy metal ions, and other contaminants are summarized. Finally, future research directions for polymer microspheres are proposed, outlining the challenges and solutions associated with the application of polymer microspheres in wastewater treatment.


Assuntos
Microesferas , Polímeros , Águas Residuárias , Poluentes Químicos da Água , Purificação da Água , Polímeros/química , Águas Residuárias/química , Purificação da Água/métodos , Adsorção , Poluentes Químicos da Água/química , Metais Pesados/química , Eliminação de Resíduos Líquidos/métodos
15.
Immunology ; 169(3): 292-308, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36726218

RESUMO

The reported enterovirus A 71 (EVA71) vaccines and immunoglobin G (IgG) antibodies have no cross-antiviral efficacy against other enterovirus A (EV-A) which caused hand, foot and mouth disease (HFMD). Here we constructed an IgM antibody (20-IgM) based on our previous discovery to address the resistance encountered by IgG-based immunotherapy. Although binding to the same conserved neutralizing epitope within the GH loop of EV-As VP1, the antiviral breath and potency of 20-IgM are still higher than its parental 20-IgG1. The 20-IgM blocks the interaction between the EV-As and its receptors, scavenger receptor class B, member 2 (SCARB2) and Kringle-containing transmembrane protein 1(KREMEN1) of the host cell. The 20-IgM also neutralizes the EV-As at the post-attachment stages, including postattachment neutralization, uncoating and RNA release inhibition after internalization. Mechanistically, the dual blockage effect of 20-IgM is dependent on both a conserved site targeting and high affinity binding. Meanwhile, 20-IgM provides cross-antiviral efficacy in EV-As orally infected neonatal ICR mice. Collectively, 20-IgM and its property exhibit excellent antiviral activity with a dual-blockage inhibitory effect at both the pre- and post-attachment stages. The finding enhances our understanding of IgM-mediated immunity and highlights the potential of IgM subtype antibodies against enterovirus infections.


Assuntos
Enterovirus Humano A , Doença de Mão, Pé e Boca , Animais , Camundongos , Anticorpos Neutralizantes , Enterovirus Humano A/química , Enterovirus Humano A/genética , Camundongos Endogâmicos ICR , Imunoglobulina G , Imunoglobulina M
16.
J Am Chem Soc ; 145(44): 24108-24115, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37788442

RESUMO

Protocells have garnered considerable attention from cell biologists, materials scientists, and synthetic biologists. Phase-separating coacervate microdroplets have emerged as a promising cytomimetic model because they can internalize and concentrate components from dilute surrounding environments. However, the membrane-free nature of such coacervates leads to coalescence into a bulk phase, a phenomenon that is not representative of the cells they are designed to mimic. Herein, we develop a membranized peptide coacervate (PC) with oppositely charged oligopeptides as the molecularly crowded cytosol and a metal-phenolic network (MPN) coating as the membrane. The hybrid protocell efficiently internalizes various bioactive macromolecules (e.g., bovine serum albumin and immunoglobulin G) (>90%) while also resisting radicals due to the semipermeable cytoprotective membrane. Notably, the resultant PC@MPNs are capable of anabolic cascade reactions and remain in discrete protocellular populations without coalescence. Finally, we demonstrate that the MPN protocell membrane can be postfunctionalized with various functional molecules (e.g., folic acid and fluorescence dye) to more closely resemble actual cells with complex membranes, such as recognition molecules, which allows for drug delivery. This membrane-bound cytosolic protocell structure paves the way for innovative synthetic cells with structural and functional complexity.


Assuntos
Células Artificiais , Células Artificiais/química , Peptídeos , Soroalbumina Bovina/química , Substâncias Macromoleculares
17.
J Am Chem Soc ; 145(28): 15331-15342, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37392396

RESUMO

Variation in the molecular architecture significantly affects the electronic and supramolecular structure of biomolecular assemblies, leading to dramatically altered piezoelectric response. However, relationship between molecular building block chemistry, crystal packing and quantitative electromechanical response is still not fully understood. Herein, we systematically explored the possibility to amplify the piezoelectricity of amino acid-based assemblies by supramolecular engineering. We show that a simple change of side-chain in acetylated amino acids leads to increased polarization of the supramolecular arrangements, resulting in significant enhancement of their piezoelectric response. Moreover, compared to most of the natural amino acid assemblies, chemical modification of acetylation increased the maximum piezoelectric tensors. The predicted maximal piezoelectric strain tensor and voltage constant of acetylated tryptophan (L-AcW) assemblies reach 47 pm V-1 and 1719 mV m/N, respectively, comparable to commonly used inorganic materials such as bismuth triborate crystals. We further fabricated an L-AcW crystal-based piezoelectric power nanogenerator that produces a high and stable open-circuit voltage of over 1.4 V under mechanical pressure. For the first time, the illumination of a light-emitting diode (LED) is demonstrated by the power output of an amino acid-based piezoelectric nanogenerator. This work presents the supramolecular engineering toward the systematic modulation of piezoelectric response in amino acid-based assemblies, facilitating the development of high-performance functional biomaterials from simple, readily available, and easily tailored building blocks.


Assuntos
Aminoácidos , Triptofano , Acetilação , Materiais Biocompatíveis , Bismuto
18.
BMC Biotechnol ; 23(1): 51, 2023 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-38049781

RESUMO

BACKGROUND: Goat rumen microbial communities are perceived as one of the most potential biochemical reservoirs of multi-functional enzymes, which are applicable to enhance wide array of bioprocesses such as the hydrolysis of cellulose and hemi-cellulose into fermentable sugar for biofuel and other value-added biochemical production. Even though, the limited understanding of rumen microbial genetic diversity and the absence of effective screening culture methods have impeded the full utilization of these potential enzymes. In this study, we applied culture independent metagenomics sequencing approach to isolate, and identify microbial communities in goat rumen, meanwhile, clone and functionally characterize novel cellulase and xylanase genes in goat rumen bacterial communities. RESULTS: Bacterial DNA samples were extracted from goat rumen fluid. Three genomic libraries were sequenced using Illumina HiSeq 2000 for paired-end 100-bp (PE100) and Illumina HiSeq 2500 for paired-end 125-bp (PE125). A total of 435gb raw reads were generated. Taxonomic analysis using Graphlan revealed that Fibrobacter, Prevotella, and Ruminococcus are the most abundant genera of bacteria in goat rumen. SPAdes assembly and prodigal annotation were performed. The contigs were also annotated using the DOE-JGI pipeline. In total, 117,502 CAZymes, comprising endoglucanases, exoglucanases, beta-glucosidases, xylosidases, and xylanases, were detected in all three samples. Two genes with predicted cellulolytic/xylanolytic activities were cloned and expressed in E. coli BL21(DE3). The endoglucanases and xylanase enzymatic activities of the recombinant proteins were confirmed using substrate plate assay and dinitrosalicylic acid (DNS) analysis. The 3D structures of endoglucanase A and endo-1,4-beta xylanase was predicted using the Swiss Model. Based on the 3D structure analysis, the two enzymes isolated from goat's rumen metagenome are unique with only 56-59% similarities to those homologous proteins in protein data bank (PDB) meanwhile, the structures of the enzymes also displayed greater stability, and higher catalytic activity. CONCLUSIONS: In summary, this study provided the database resources of bacterial metagenomes from goat's rumen fluid, including gene sequences with annotated functions and methods for gene isolation and over-expression of cellulolytic enzymes; and a wealth of genes in the metabolic pathways affecting food and nutrition of ruminant animals.


Assuntos
Celulase , Celulases , Animais , Celulase/metabolismo , Metagenoma , Cabras/genética , Cabras/metabolismo , Cabras/microbiologia , Rúmen/metabolismo , Rúmen/microbiologia , Escherichia coli/genética , Bactérias , Celulases/genética , Celulose
19.
Arch Virol ; 168(8): 217, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37524962

RESUMO

Coxsackievirus A10 (CV-A10) is recognized as one of the most important pathogens associated with hand, foot, and mouth disease (HFMD) in young children under 5 years of age worldwide, and it can lead to fatal neurological complications. However, available commercial vaccines fail to protect against CV-A10. Therefore, there is an urgent need to study new protein targets of CV-A10 and develop novel vaccine-based therapeutic strategies. Advances in proteomics in recent years have enabled a comprehensive understanding of host pathogen interactions. Here, to study CV-A10-host interactions, a global quantitative proteomic analysis was conducted to investigate the molecular characteristics of host cell proteins and identify key host proteins involved in CV-A10 infection. Using tandem mass tagging (TMT)-based mass spectrometry, a total of 6615 host proteins were quantified, with 293 proteins being differentially regulated. To ensure the validity and reliability of the proteomics data, three randomly selected proteins were verified by Western blot analysis, and the results were consistent with the TMT results. Further functional analysis showed that the upregulated and downregulated proteins were associated with diverse biological activities and signaling pathways, such as metabolic processes, biosynthetic processes, the AMPK signaling pathway, the neurotrophin signaling pathway, the MAPK signaling pathway, and the GABAergic synaptic signaling. Moreover, subsequent bioinformatics analysis demonstrated that these differentially expressed proteins contained distinct domains, were localized in different subcellular components, and generated a complex network. Finally, high-mobility group box 1 (HMGB1) might be a key host factor involved in CV-A10 replication. In summary, our findings provide comprehensive insights into the proteomic profile during CV-A10 infection, deepen our understanding of the relationship between CV-A10 and host cells, and establish a proteomic signature for this viral infection. Moreover, the observed effect of HMGB1 on CV-A10 replication suggests that it might be a potential therapeutic target treatment of CV-A10 infection.


Assuntos
Proteína HMGB1 , Doença de Mão, Pé e Boca , Criança , Humanos , Pré-Escolar , Proteína HMGB1/genética , Proteômica , Reprodutibilidade dos Testes , Proteínas , Replicação Viral
20.
Environ Sci Technol ; 57(48): 19341-19351, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37934861

RESUMO

Polystyrene nanoplastics (PS-NPs) are emerging environmental contaminants that are ubiquitously detected in various environments and have toxic effects on various organisms. Nevertheless, the transgenerational reproductive toxicity and underlying mechanisms of PS-NPs remain largely unknown, especially for photoaged PS-NPs under ultraviolet irradiation. In this study, only the parental generation (P0) was exposed to virgin and aged PS-NPs at environmentally relevant concentrations (0.1-100 µg/L), and subsequent generations (F1-F4) were cultured under normal conditions. Ultraviolet irradiation induced the generation of environmentally persistent free radicals and reactive oxygen species, which altered the physical and chemical characteristics of PS-NPs. The results of toxicity testing suggested that exposure to aged PS-NPs caused a more severe decrease in brood size, egg ejection rate, number of fertilized eggs, and hatchability than did the virgin PS-NPs in the P0, F1, and F2 generations. Additionally, a single maternal exposure to aged PS-NPs resulted in transgenerational effects on fertility in the F1 and F2 generations. Increased levels of H3K4 and H3K9 methylation were observed in the F1 and F2 generations, which were concomitant with the transgenerational downregulation of the expression of associated genes, such as spr-5, set-17, and met-2. On the basis of correlation analyses, the levels of histone methylation and the expression of these genes were significantly correlated to transgenerational reproductive effects. Further research showed that transgenerational effects on fertility were not observed in spr-5(by134), met-2(n4256), and set-17(n5017) mutants. Overall, maternal exposure to aged PS-NPs induced transgenerational reproductive effects via H3K4 and H3K9 methylation, and the spr-5, met-2, and set-17 genes were involved in the regulation of transgenerational toxicity. This study provides new insights into the potential risks of photoaging PS-NPs in the environment.


Assuntos
Caenorhabditis elegans , Histonas , Animais , Feminino , Caenorhabditis elegans/genética , Histonas/genética , Histonas/farmacologia , Metilação , Poliestirenos/toxicidade , Microplásticos
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