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1.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38031362

RESUMO

Fractal patterns have been shown to change in resting- and task-state blood oxygen level-dependent signals in bipolar disorder patients. However, fractal characteristics of brain blood oxygen level-dependent signals when responding to external emotional stimuli in pediatric bipolar disorder remain unclear. Blood oxygen level-dependent signals of 20 PBD-I patients and 17 age- and sex-matched healthy controls were extracted while performing an emotional Go-Nogo task. Neural responses relevant to the task and Hurst exponent of the blood oxygen level-dependent signals were assessed. Correlations between clinical indices and Hurst exponent were estimated. Significantly increased activations were found in regions covering the frontal lobe, parietal lobe, temporal lobe, insula, and subcortical nuclei in PBD-I patients compared to healthy controls in contrast of emotional versus neutral distractors. PBD-I patients exhibited higher Hurst exponent in regions that involved in action control, such as superior frontal gyrus, inferior frontal gyrus, inferior temporal gyrus, and insula, with Hurst exponent of frontal orbital gyrus correlated with onset age. The present study exhibited overactivation, increased self-similarity and decreased complexity in cortical regions during emotional Go-Nogo task in patients relative to healthy controls, which provides evidence of an altered emotional modulation of cognitive control in pediatric bipolar disorder patients. Hurst exponent may be a fractal biomarker of neural activity in pediatric bipolar disorder.


Assuntos
Transtorno Bipolar , Humanos , Criança , Transtorno Bipolar/diagnóstico por imagem , Transtorno Bipolar/psicologia , Encéfalo/diagnóstico por imagem , Emoções/fisiologia , Lobo Frontal , Córtex Pré-Frontal , Mapeamento Encefálico , Imageamento por Ressonância Magnética
2.
Nano Lett ; 24(19): 5831-5837, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38708822

RESUMO

Single lanthanide (Ln) ion doped upconversion nanoparticles (UCNPs) exhibit great potential for biomolecule sensing and counting. Plasmonic structures can improve the emission efficiency of single UCNPs by modulating the energy transferring process. Yet, achieving robust and large-area single UCNP emission modulation remains a challenge, which obstructs investigation and application of single UCNPs. Here, we present a strategy using metal nanohole arrays (NHAs) to achieve energy-transfer modulation on single UCNPs simultaneously within large-area plasmonic structures. By coupling surface plasmon polaritons (SPPs) with higher-intermediate state (1D2 → 3F3, 1D2 → 3H4) transitions, we achieved a remarkable up to 10-fold enhancement in 800 nm emission, surpassing the conventional approach of coupling SPPs with an intermediate ground state (3H4 → 3H6). We numerically simulate the electrical field distribution and reveal that luminescent enhancement is robust and insensitive to the exact location of particles. It is anticipated that the strategy provides a platform for widely exploring applications in single-particle quantitative biosensing.

3.
Mol Biol Evol ; 40(1)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36617265

RESUMO

Recent studies have increasingly pointed to microRNAs (miRNAs) as the agent of gene regulatory network (GRN) stabilization as well as developmental canalization against constant but small environmental perturbations. To analyze mild perturbations, we construct a Dicer-1 knockdown line (dcr-1 KD) in Drosophila that modestly reduces all miRNAs by, on average, ∼20%. The defining characteristic of stabilizers is that, when their capacity is compromised, GRNs do not change their short-term behaviors. Indeed, even with such broad reductions across all miRNAs, the changes in the transcriptome are very modest during development in stable environment. By comparison, broad knockdowns of other regulatory genes (esp. transcription factors) by the same method should lead to drastic changes in the GRNs. The consequence of destabilization may thus be in long-term development as postulated by the theory of canalization. Flies with modest miRNA reductions may gradually deviate from the developmental norm, resulting in late-stage failures such as shortened longevity. In the optimal culture condition, the survival to adulthood is indeed normal in the dcr-1 KD line but, importantly, adult longevity is reduced by ∼90%. When flies are stressed by high temperature, dcr-1 KD induces lethality earlier in late pupation and, as the perturbations are shifted earlier, the affected stages are shifted correspondingly. Hence, in late stages of development with deviations piling up, GRN would be increasingly in need of stabilization. In conclusion, miRNAs appear to be a solution to weak but constant environmental perturbations.


Assuntos
MicroRNAs , Transcriptoma , Animais , MicroRNAs/genética , Drosophila/genética , Longevidade , Fenótipo , Redes Reguladoras de Genes
4.
Radiology ; 313(1): e233354, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39404624

RESUMO

Background Coronary CT-derived fractional flow reserve (CT-FFR) has been used in patients with suspected coronary artery disease (CAD); however, whether it decreases invasive coronary angiography (ICA) use and affects prognosis remains insufficiently evidenced. Purpose To explore the effectiveness of adding CT-FFR to routine coronary CT angiography (CCTA) on short-term ICA rate and major adverse cardiovascular events (MACE) in a Chinese setting. Materials and Methods A multicenter randomized controlled trial was conducted in 17 Chinese centers, with patient inclusion from May 2021 to September 2021. Eligible individuals with 25%-99% stenosis at CCTA were randomly assigned 1:1 to a strategy of CCTA plus automated CT-FFR or CCTA alone for guiding downstream care. The primary end point was the ICA rate 90 days after enrollment. Secondary end points included 90-day and 1-year MACE rates (comprised of all-cause mortality, nonfatal myocardial infarction, and urgent revascularization) and 1-year cardiac events (comprised of cardiac death, nonfatal myocardial infarction, and urgent revascularization). The Cox proportional hazards model with center effect adjustment was used for survival comparisons. Results A total of 5297 participants (mean age, 63.5 years ± 10.8 [SD]; 3178 male) were included. During the 90-day follow-up, ICA was performed in 263 of 2633 participants (10.0%) in the CCTA plus CT-FFR group and 327 of 2640 participants (12.4%) in the CCTA-alone group (absolute rate difference: -2.40%; 95% CI: -4.10, -0.70; P = .006). The MACE rates at 90 days (0.5% [12 of 2633 participants] vs 0.8% [21 of 2640 participants]; P = .12) and 1 year (2.9% [74 of 2546 participants] vs 2.8% [72 of 2531 participants]; P = .90) were similar for both groups. At 1-year follow-up, fewer cardiac events were observed in the CCTA plus CT-FFR group compared with the CCTA-alone group (0.5% vs 1.1%; adjusted hazard ratio: 0.52; 95% CI: 0.27, 0.99; P = .047). Conclusion CT-FFR added to CCTA led to a lower 90-day ICA rate and similar 1-year MACE rate in a Chinese real-world setting. Further follow-up is warranted to demonstrate the long-term prognostic value of this management approach. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Pundziute-do Prado in this issue.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico , Humanos , Masculino , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Feminino , Pessoa de Meia-Idade , Angiografia por Tomografia Computadorizada/métodos , China , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Idoso , População do Leste Asiático
5.
Clin Genet ; 106(1): 27-36, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38342987

RESUMO

Oligoasthenoteratozoospermia (OAT) is a common type of male infertility; however, its genetic causes remain largely unknown. Some of the genetic determinants of OAT are gene defects affecting spermatogenesis. BCORL1 (BCL6 corepressor like 1) is a transcriptional corepressor that exhibits the OAT phenotype in a knockout mouse model. A hemizygous missense variant of BCORL1 (c.2615T > G:p.Val872Gly) was reported in an infertile male patient with non-obstructive azoospermia (NOA). Nevertheless, the correlation between BCORL1 variants and OAT in humans remains unknown. In this study, we used whole-exome sequencing to identify a novel hemizygous nonsense variant of BCORL1 (c.1564G > T:p.Glu522*) in a male patient with OAT from a Han Chinese family. Functional analysis showed that the variant produced a truncated protein with altered cellular localization and a dysfunctional interaction with SKP1 (S-phase kinase-associated protein 1). Further population screening identified four BCORL1 missense variants in subjects with both OAT (1 of 325, 0.31%) and NOA (4 of 355, 1.13%), but no pathogenic BCORL1 variants among 362 fertile subjects. In conclusion, our findings indicate that BCORL1 is a potential candidate gene in the pathogenesis of OAT and NOA, expanded its disease spectrum and suggested that BCORL1 may play a role in spermatogenesis by interacting with SKP1.


Assuntos
Sequenciamento do Exoma , Infertilidade Masculina , Proteínas Repressoras , Masculino , Humanos , Proteínas Repressoras/genética , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Oligospermia/genética , Oligospermia/patologia , Adulto , Linhagem , Azoospermia/genética , Azoospermia/patologia , Mutação com Perda de Função/genética , Predisposição Genética para Doença , Proteína-Arginina N-Metiltransferases/genética , Mutação de Sentido Incorreto/genética , Espermatogênese/genética
6.
Hum Reprod ; 39(4): 849-855, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38420683

RESUMO

Individuals with 46,XX/XY chimerism can display a wide range of characteristics, varying from hermaphroditism to complete male or female, and can display sex chromosome chimerism in multiple tissues, including the gonads. The gonadal tissues of females contain both granulosa and germ cells. However, the specific sex chromosome composition of the granulosa and germ cells in 46,XX/XY chimeric female is currently unknown. Here, we reported a 30-year-old woman with secondary infertility who displayed a 46,XX/46,XY chimerism in the peripheral blood. FISH testing revealed varying degrees of XX/XY chimerism in multiple tissues of the female patient. Subsequently, the patient underwent preimplantation genetic testing (PGT) treatment, and 26 oocytes were retrieved. From the twenty-four biopsied mature oocytes, a total of 23 first polar bodies (PBs) and 10 second PBs were obtained. These PBs and two immature metaphase I (MI) oocytes only displayed X chromosome signals with no presence of the Y, suggesting that all oocytes in this chimeric female were of XX germ cell origin. On the other hand, granulosa cells obtained from individual follicles exhibited varied proportions of XX/XY cell types, and six follicles possessed 100% XX or XY granulosa cells. A total of 24 oocytes were successfully fertilized, and 12 developed into blastocysts, where 5 being XY and 5 were XX. Two blastocysts were transferred with one originating from an oocyte aspirated from a follicle containing 100% XY granulosa cells. This resulted in a twin pregnancy. Subsequent prenatal diagnosis confirmed normal male and female karyotypes. Ultimately, healthy boy-girl twins were delivered at full term. In summary, this 46,XX/XY chimerism with XX germ cells presented complete female, suggesting that germ cells may exert a significant influence on the sexual determination of an individual, which provide valuable insights into the intricate processes associated with sexual development and reproduction.


Assuntos
Quimerismo , Células Germinativas , Disgenesia Gonadal 46 XY , Adulto , Feminino , Humanos , Masculino , Gravidez , Gônadas , Oócitos , Cromossomo X
7.
Cell Commun Signal ; 22(1): 177, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38475811

RESUMO

BACKGROUND: The incidence of multiple myeloma (MM), a type of blood cancer affecting monoclonal plasma cells, is rising. Although new drugs and therapies have improved patient outcomes, MM remains incurable. Recent studies have highlighted the crucial role of the chemokine network in MM's pathological mechanism. Gaining a better understanding of this network and creating an overview of chemokines in MM could aid in identifying potential biomarkers and developing new therapeutic strategies and targets. PURPOSE: To summarize the complicated role of chemokines in MM, discuss their potential as biomarkers, and introduce several treatments based on chemokines. METHODS: Pubmed, Web of Science, ICTRP, and Clinical Trials were searched for articles and research related to chemokines. Publications published within the last 5 years are selected. RESULTS: Malignant cells can utilize chemokines, including CCL2, CCL3, CCL5, CXCL7, CXCL8, CXCL12, and CXCL13 to evade apoptosis triggered by immune cells or medication, escape from bone marrow and escalate bone lesions. Other chemokines, including CXCL4, CCL19, and CXCL10, may aid in recruiting immune cells, increasing their cytotoxicity against cancer cells, and inducing apoptosis of malignant cells. CONCLUSION: Utilizing anti-tumor chemokines or blocking pro-tumor chemokines may provide new therapeutic strategies for managing MM. Inspired by developed CXCR4 antagonists, including plerixafor, ulocuplumab, and motixafortide, more small molecular antagonists or antibodies for pro-tumor chemokine ligands and their receptors can be developed and used in clinical practice. Along with inhibiting pro-tumor chemokines, studies suggest combining chemokines with chimeric antigen receptor (CAR)-T therapy is promising and efficient.


Assuntos
Compostos Heterocíclicos , Mieloma Múltiplo , Humanos , Mobilização de Células-Tronco Hematopoéticas , Quimiocinas , Transdução de Sinais , Biomarcadores
8.
Mol Pharm ; 21(3): 1149-1159, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38288708

RESUMO

The development of biomolecule delivery systems is essential for the treatment of various diseases such as cancer, immunological diseases, and metabolic disorders. For the first time, we found that SARS-CoV-2-encoded nonstructural protein 2 (NSP2) can be secreted from the cells, where it is synthesized. Brefeldin A and H89, inhibitors of ER/Golgi secretion pathways, did not inhibit NSP2 secretion. NSP2 is likely secreted via an unconventional secretory pathway. Moreover, both secreted and purified NSP2 proteins were able to traverse the plasma membrane barrier and enter both immortalized human umbilical vein endothelial cells and tumor cell lines. After entry, the NSP2 protein was localized in only the cytoplasm. Cytochalasin D, a potent inhibitor of actin polymerization, inhibited the entry of NSP2. NSP2 can carry other molecules into cells. Burkholderia lethal factor 1, a monomeric toxin from the intracellular pathogen Burkholderia pseudomallei, has demonstrated antitumor activity by targeting host eukaryotic initiation translation factor 4A. An NSP2-BLF1 fusion protein was translocated across the cellular membranes of Huh7 cells and mediated cell killing. By using different approaches, including protein purification, chemical inhibition, and cell imaging, we confirm that NSP2 is able to deliver heterologous proteins into cells. NSP2 can act as a potential delivery vehicle for proteins.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo , Células Endoteliais/metabolismo , Linhagem Celular Tumoral
9.
Eur Radiol ; 34(1): 402-410, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37552255

RESUMO

OBJECTIVES: To evaluate the prognostic value of radiomics features based on late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) images in patients with cardiac amyloidosis (CA). METHODS: This retrospective study included 120 CA patients undergoing CMR at three institutions. Radiomics features were extracted from global and three different segments (base, mid-ventricular, and apex) of left ventricular (LV) on short-axis LGE images. Primary endpoint was all-cause mortality. The predictive performance of the radiomics features and semi-quantitative and quantitative LGE parameters were compared by ROC. The AUC was used to observe whether Rad-score had an incremental value for clinical stage. The Kaplan-Meier curve was used to further stratify the risk of CA patients. RESULTS: During a median follow-up of 12.9 months, 30% (40/120) patients died. There was no significant difference in the predictive performance of the radiomics model in different LV sections in the validation set (AUCs of the global, basal, middle, and apical radiomics model were 0.75, 0.77, 0.76, and 0.77, respectively; all p > 0.05). The predictive performance of the Rad-score of the base-LV was better than that of the LGE total enhancement mass (AUC:0.77 vs. 0.54, p < 0.001) and LGE extent (AUC: 0.77 vs. 0.53, p = 0.004). Rad-score combined with Mayo stage had better predictive performance than Mayo stage alone (AUC: 0.86 vs. 0.81, p = 0.03). Rad-score (≥ 0.66) contributed to the risk stratification of all-cause mortality in CA. CONCLUSIONS: Compared to quantitative LGE parameters, radiomics can better predict all-cause mortality in CA, while the combination of radiomics and Mayo stage could provide higher predictive accuracy. CLINICAL RELEVANCE STATEMENT: Radiomics analysis provides incremental value and improved risk stratification for all-cause mortality in patients with cardiac amyloidosis. KEY POINTS: • Radiomics in LV-base was superior to LGE semi-quantitative and quantitative parameters for predicting all-cause mortality in CA. • Rad-score combined with Mayo stage had better predictive performance than Mayo stage alone or radiomics alone. • Rad-score ≥ 0.66 was associated with a significantly increased risk of all-cause mortality in CA patients.


Assuntos
Amiloidose , Gadolínio , Humanos , Gadolínio/farmacologia , Meios de Contraste/farmacologia , Estudos Retrospectivos , Radiômica , Amiloidose/diagnóstico por imagem , Prognóstico , Valor Preditivo dos Testes , Imagem Cinética por Ressonância Magnética/métodos , Função Ventricular Esquerda
10.
Dig Dis ; 42(3): 221-229, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38342087

RESUMO

INTRODUCTION: The objective of our study was to develop a nomogram to predict overall survival (OS) and cancer-specific survival (CSS) in patients with gastric signet ring cell carcinoma (GSRCC). METHODS: A total of 3,408 GSRCC patients between 1975 and 2017 were screened from the Surveillance, Epidemiology, and End Results (SEER) database and randomly divided into training and validation cohorts. Univariate and multivariate Cox analyses were conducted to identify independent prognostic factors for the construction of a nomogram. The performance of the model was then assessed by the concordance index (C-index), calibration plot, and area under the receiver operating characteristic curve (AUC). Then, the novel nomogram was further assessed by 64 GSRCC patients from our hospital as the external cohort. RESULTS: We identified age, tumor lymph node metastasis (TNM) staging system, surgery, and chemotherapy as significant independent elements of prognosis. On this basis, a nomogram was constructed, with a C-index of OS in the training and validation cohorts of 0.763 (95% CI: 0.751-0.774) and 0.766 (95% CI: 0.748-0.784) and a C-index of CSS of 0.765 (95% CI: 0.753-0.777) and 0.773 (95% CI: 0.755-0.791), respectively. The AUCs of the nomogram for predicting 2- and 5-year OS were 0.848 and 0.885, respectively, and those for predicting CSS were 0.854 and 0.899, respectively, demonstrating the excellent predictive value of the constructed nomogram compared to the traditional AJCC staging system. Similar results were also observed in both the internal and external validation sets. CONCLUSION: The nomogram provided an accurate tool to predict OS and CSS in patients with GSRCC, which can assist clinicians in making predictions about individual patient survival.


Assuntos
Carcinoma de Células em Anel de Sinete , Nomogramas , Programa de SEER , Neoplasias Gástricas , Humanos , Carcinoma de Células em Anel de Sinete/mortalidade , Carcinoma de Células em Anel de Sinete/patologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Prognóstico , Idoso , Adulto , Estadiamento de Neoplasias , Curva ROC , Modelos de Riscos Proporcionais
11.
Neuroradiology ; 66(3): 409-416, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38191867

RESUMO

PURPOSE: Endovascular reconstruction has emerged as a viable alternative for carotid artery dissections (CADs) that are unresponsive to antithrombotic therapy. However, high cervical and long-segment CADs pose challenges during endovascular treatment due to their distal location and tortuous anatomy. We presented our experiences using endovascular reconstruction with the Leo plus stent for this type of CAD. METHODS: We conducted a retrospective review of patients with high cervical and long-segment CADs treated using the Leo plus stent. We analyzed patient demographics, clinical presentations, procedural features, complications, and follow-up outcomes. RESULTS: A total of 17 patients (mean age, 48.1 years) with 17 CADs were identified. Seven of these dissections were accompanied by pseudoaneurysm. The mean length of the dissection was 5.7 cm, and the mean degree of stenosis was 92.3%. A single Leo plus stent was deployed in 15 patients, while another Wallstent carotid stent was used in 2 cases. All stents were successfully positioned in their intended sites. The average degree of residual stenosis was 22.2%. There were no perioperative complications. With a median follow-up duration of 29 months, no ischemic stroke events occurred. All but one Leo plus stent remained patent during follow-up, and all 7 pseudoaneurysms had disappeared at the last radiological assessment. CONCLUSION: Our experience in treating high cervical and long-segment CADs with the Leo plus stent demonstrates that this approach is practical, safe, and effective, as evidenced by long-term observations. The Leo Plus stent appears to be a suitable option for managing this type of CAD.


Assuntos
Dissecção Aórtica , Dissecação da Artéria Carótida Interna , Procedimentos Endovasculares , Humanos , Pessoa de Meia-Idade , Dissecação da Artéria Carótida Interna/diagnóstico por imagem , Dissecação da Artéria Carótida Interna/cirurgia , Constrição Patológica/complicações , Resultado do Tratamento , Stents , Estudos Retrospectivos , Artérias Carótidas
12.
J Med Genet ; 60(2): 144-153, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35387802

RESUMO

BACKGROUND: The genetic causes for most male infertility due to severe oligoasthenoteratozoospermia (OAT) remain unclear. OBJECTIVE: To identify the genetic cause of male infertility characterised by OAT. METHODS: Variant screening was performed by whole-exome sequencing from 325 infertile patients with OAT and 392 fertile individuals. In silico and in vitro analyses were performed to evaluate the impacts of candidate disease-causing variants. A knockout mouse model was generated to confirm the candidate disease-causing gene, and intracytoplasmic sperm injection (ICSI) was used to evaluate the efficiency of clinical treatment. RESULTS: We identified biallelic CFAP61 variants (NM_015585.4: c.1654C>T (p.R552C) and c.2911G>A (p.D971N), c.144-2A>G and c.1666G>A (p.G556R)) in two (0.62%) of the 325 OAT-affected men. In silico bioinformatics analysis predicted that all four variants were deleterious, and in vitro functional analysis confirmed the deleterious effects of the mutants. Notably, H&E staining and electron microscopy analyses of the spermatozoa revealed multiple morphological abnormalities of sperm flagella, the absence of central pair microtubules and mitochondrial sheath malformation in sperm flagella from man with CFAP61 variants. Further immunofluorescence assays revealed markedly reduced CFAP61 staining in the sperm flagella. In addition, Cfap61-deficient mice showed the OAT phenotype, suggesting that loss of function of CFAP61 was the cause of OAT. Two individuals accepted ICSI therapy using their own ejaculated sperm, and one of them succeeded in fathering a healthy baby. CONCLUSIONS: Our findings indicate that CFAP61 is essential for spermatogenesis and that biallelic CFAP61 variants lead to male infertility in humans and mice with OAT.


Assuntos
Anormalidades Múltiplas , Astenozoospermia , Infertilidade Masculina , Oligospermia , Humanos , Masculino , Animais , Camundongos , Infertilidade Masculina/genética , Oligospermia/genética , Astenozoospermia/genética , Sêmen , Espermatozoides , Anormalidades Múltiplas/genética
13.
Proc Natl Acad Sci U S A ; 118(30)2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34301892

RESUMO

Cytidine triphosphate synthase (CTPS), which comprises an ammonia ligase domain and a glutamine amidotransferase domain, catalyzes the final step of de novo CTP biosynthesis. The activity of CTPS is regulated by the binding of four nucleotides and glutamine. While glutamine serves as an ammonia donor for the ATP-dependent conversion of UTP to CTP, the fourth nucleotide GTP acts as an allosteric activator. Models have been proposed to explain the mechanisms of action at the active site of the ammonia ligase domain and the conformational changes derived by GTP binding. However, actual GTP/ATP/UTP binding modes and relevant conformational changes have not been revealed fully. Here, we report the discovery of binding modes of four nucleotides and a glutamine analog 6-diazo-5-oxo-L-norleucine in Drosophila CTPS by cryo-electron microscopy with near-atomic resolution. Interactions between GTP and surrounding residues indicate that GTP acts to coordinate reactions at both domains by directly blocking ammonia leakage and stabilizing the ammonia tunnel. Additionally, we observe the ATP-dependent UTP phosphorylation intermediate and determine interacting residues at the ammonia ligase. A noncanonical CTP binding at the ATP binding site suggests another layer of feedback inhibition. Our findings not only delineate the structure of CTPS in the presence of all substrates but also complete our understanding of the underlying mechanisms of the allosteric regulation and CTP synthesis.


Assuntos
Trifosfato de Adenosina/metabolismo , Amônia/metabolismo , Carbono-Nitrogênio Ligases/química , Carbono-Nitrogênio Ligases/metabolismo , Drosophila melanogaster/enzimologia , Glutamina/metabolismo , Uridina Trifosfato/metabolismo , Regulação Alostérica , Animais , Sítios de Ligação , Catálise , Microscopia Crioeletrônica , Hidrólise , Cinética , Ligantes , Conformação Proteica
14.
Molecules ; 29(18)2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39339476

RESUMO

Poly(N-isopropylacrylamide) (PNIPAM) offers a promising platform for non-invasive and gentle cell detachment. However, conventional PNIPAM-based substrates often suffer from limitations including limited stability and reduced reusability, which hinder their widespread adoption in biomedical applications. In this study, PNIPAM copolymer films were formed on the surfaces of glass slides or silicon wafers using a two-step film-forming method involving coating and grafting. Subsequently, a comprehensive analysis of the films' surface wettability, topography, and thickness was conducted using a variety of techniques, including contact angle analysis, atomic force microscopy (AFM), and ellipsometric measurements. Bone marrow mesenchymal stem cells (BMMSCs) were then seeded onto PNIPAM copolymer films prepared from different copolymer solution concentrations, ranging from 0.2 to 10 mg·mL-1, to select the optimal culture substrate that allowed for good cell growth at 37 °C and effective cell detachment through temperature reduction. Furthermore, the stability and reusability of the optimal copolymer films were assessed. Finally, AFM and X-ray photoelectron spectroscopy (XPS) were employed to examine the surface morphology and elemental composition of the copolymer films after two rounds of BMMSC adhesion and detachment. The findings revealed that the surface properties and overall characteristics of PNIPAM copolymer films varied significantly with the solution concentration. Based on the selection criteria, the copolymer films derived from 1 mg·mL-1 solution were identified as the optimal culture substrates for BMMSCs. After two rounds of cellular adhesion and detachment, some proteins remained on the film surfaces, acting as a foundation for subsequent cellular re-adhesion and growth, thereby implicitly corroborating the practicability and reusability of the copolymer films. This study not only introduces a stable and efficient platform for stem cell culture and harvesting but also represents a significant advance in the fabrication of smart materials tailored for biomedical applications.


Assuntos
Resinas Acrílicas , Adesão Celular , Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Resinas Acrílicas/química , Adesão Celular/efeitos dos fármacos , Técnicas de Cultura de Células/métodos , Propriedades de Superfície , Proliferação de Células/efeitos dos fármacos , Temperatura , Animais , Microscopia de Força Atômica , Células Cultivadas , Células da Medula Óssea/citologia
15.
Arch Orthop Trauma Surg ; 144(5): 1889-1900, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38436716

RESUMO

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: There is some controversy about the effects of calcitonin (CT) on lumbar spinal stenosis (LSS). This systematic review and meta-analysis is to assess the strength of the evidence supporting the use of CT in the treatment of patients with LSS. MATERIAL AND METHOD: We performed an electronic search depicting randomized controlled trials (RCTs) through 4 databases from the date of database creation to January 2023. 3 different researchers conducted independent literature screening, data extractions, and quality assessments. The outcome measures included visual analogue scale (VAS), walking distance, and oswestry disability index (ODI). Meta-analysis and trial sequence analysis (TSA) were carried out using RevMan 5.4, Stata 16.0, and TSA 0.9. GRADE 3.6 was used to evaluate the evidence quality. RESULTS: We accepted 9 studies with 496 participants. The meta-analysis revealed that CT offered no significant improvement in VAS, walking distance, or ODI in patients with LSS. CONCLUSION: There is no evidence that CT has a benefit in patients with LSS, either alone or in combination with other treatments, or depending on the route of administration, according to the systematic review and meta-analysis of relevant RCTs.


Assuntos
Calcitonina , Vértebras Lombares , Estenose Espinal , Humanos , Conservadores da Densidade Óssea/uso terapêutico , Calcitonina/uso terapêutico , Avaliação da Deficiência , Vértebras Lombares/diagnóstico por imagem , Medição da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto , Estenose Espinal/tratamento farmacológico
16.
J Am Chem Soc ; 145(4): 2544-2552, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36661080

RESUMO

Fashioning microporous covalent organic frameworks (COFs) into single crystals with ordered macropores allows for an effective reduction of the mass transfer resistance and the maximum preservation of their intrinsic properties but remains unexplored. Here, we report the first synthesis of three-dimensional (3D) ordered macroporous single crystals of the imine-linked 3D microporous COFs (COF-300 and COF-303) via a template-assisted modulated strategy. In this strategy, COFs crystallized within the sacrificial colloidal crystal template, assembled from monodisperse polystyrene microspheres, and underwent an aniline-modulated amorphous-to-crystalline transformation to form large single crystals with 3D interconnected macropores. The effects of the introduced macroporous structure on the sorption performances of COF-300 single crystals were further probed by iodine. Our results indicate that iodine adsorption occurred in micropores of COF-300 but not in the introduced macropores. Accordingly, the iodine adsorption capacity of COF single crystals was governed by their micropore accessibility. The relatively long diffusion path in the non-macroporous COF-300 single crystals resulted in a limited micropore accessibility (48.4%) and thus a low capacity in iodine adsorption (1.48 g·g-1). The introduction of 3D ordered macropores can greatly shorten the microporous diffusion path in COF-300 single crystals and thus render all their micropores fully accessible in iodine adsorption with a capacity (3.15 g·g-1) that coincides well with the theoretical one.

17.
J Am Chem Soc ; 145(47): 25570-25578, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37967022

RESUMO

Effective control over the crystallization of metal-organic framework (MOF) films is of great importance not only for the performance study and optimization in related applications but also for the fundamental understanding of the involved reticular chemistry. Featuring many technological advantages, electrochemical synthesis has been extensively reported for many MOF materials but is still challenged by the production of dense oriented films with a large-range tuning of thickness. Here, we report a ligand-oxidation-based anodic strategy capable of synthesizing oriented films of two-dimensional (2D) and three-dimensional (3D) conductive M-catecholate MOFs (2D Cu3(HHTP)2, 2D Zn3(HHTP)2, 2D Co3(HHTP)2, 3D YbHHTP, and 2D Cu2TBA) with tunable thicknesses up to tens of micrometers on commonly used electrodes. This anodic strategy relies on the oxidation of redox-active catechol ligands and follows a stepwise electrochemical-chemical reaction mechanism to achieve effective control over crystallizing M-catecholate MOFs into films oriented in the [001] direction. Benefiting from the electrically conductive nature, Cu3(HHTP)2 films could be thickened at a steady rate (17.4 nm·min-1) from ∼90 nm to 10.7 µm via a growth mechanism differing from those adopted in previous electrochemical synthesis of dense MOF films with limited thickness due to the self-inhibition effect. This anodic synthesis could be further combined with a templating strategy to fabricate not only films with well-defined 2D features in sizes from micrometers to millimeters but also high aspect ratio mesostructures, such as nanorods, of Cu3(HHTP)2.

18.
Mol Biol Evol ; 39(7)2022 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-35687719

RESUMO

Due to extensive pleiotropy, trans-acting elements are often thought to be evolutionarily constrained. While the impact of trans-acting elements on gene expression evolution has been extensively studied, relatively little is understood about the contribution of a single trans regulator to interspecific expression and phenotypic divergence. Here, we disentangle the effects of genomic context and miR-983, an adaptively evolving young microRNA, on expression divergence between Drosophila melanogaster and D. simulans. We show miR-983 effects promote interspecific expression divergence in testis despite its antagonism with the often-predominant context effects. Single-cyst RNA-seq reveals that distinct sets of genes gain and lose miR-983 influence under disruptive or diversifying selection at different stages of spermatogenesis, potentially helping minimize antagonistic pleiotropy. At the round spermatid stage, the effects of miR-983 are weak and distributed, coincident with the transcriptome undergoing drastic expression changes. Knocking out miR-983 causes reduced sperm length with increased within-individual variation in D. melanogaster but not in D. simulans, and the D. melanogaster knockout also exhibits compromised sperm defense ability. Our results provide empirical evidence for the resolution of antagonistic pleiotropy and also have broad implications for the function and evolution of new trans regulators.


Assuntos
Drosophila , MicroRNAs , Animais , Drosophila/genética , Drosophila melanogaster/genética , Masculino , MicroRNAs/genética , Sêmen , Especificidade da Espécie , Espermatogênese/genética
19.
Plant Biotechnol J ; 21(10): 1978-1989, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37341033

RESUMO

The number of pollen grains is a critical determinant of reproductive success in seed plants and varies among species and individuals. However, in contrast with many mutant-screening studies relevant to anther and pollen development, the natural genetic basis for variations in pollen number remains largely unexplored. To address this issue, we carried out a genome-wide association study in maize, ultimately revealing that a large presence/absence variation in the promoter region of ZmRPN1 alters its expression level and thereby contributes to pollen number variation. Molecular analyses showed that ZmRPN1 interacts with ZmMSP1, which is known as a germline cell number regulator, and facilitates ZmMSP1 localization to the plasma membrane. Importantly, ZmRPN1 dysfunction resulted in a substantial increase in pollen number, consequently boosting seed production by increasing female-male planting ratio. Together, our findings uncover a key gene controlling pollen number, and therefore, modulation of ZmRPN1 expression could be efficiently used to develop elite pollinators for modern hybrid maize breeding.


Assuntos
Estudo de Associação Genômica Ampla , Zea mays , Zea mays/metabolismo , Melhoramento Vegetal , Pólen/genética , Sementes/genética
20.
Hum Reprod ; 38(7): 1390-1398, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37140151

RESUMO

STUDY QUESTION: What is the effect of defects in the manchette protein IQ motif-containing N (IQCN) on sperm flagellar assembly? SUMMARY ANSWER: Deficiency in IQCN causes sperm flagellar assembly defects and male infertility. WHAT IS KNOWN ALREADY: The manchette is a transient structure that is involved in the shaping of the human spermatid nucleus and protein transport within flagella. Our group recently reported that the manchette protein IQCN is essential for fertilization. Variants in IQCN lead to total fertilization failure and defective acrosome structure phenotypes. However, the function of IQCN in sperm flagellar assembly is still unknown. STUDY DESIGN, SIZE, DURATION: Fifty men with infertility were recruited from a university-affiliated center from January 2014 to October 2022. PARTICIPANTS/MATERIALS, SETTING, METHODS: Genomic DNA was extracted from the peripheral blood samples of all 50 individuals for whole-exome sequencing. The ultrastructure of the spermatozoa was assessed by transmission electron microscopy. Computer-assisted sperm analysis (CASA) was used to test the parameters of curvilinear velocity (VCL), straight-line velocity (VSL), and average path velocity (VAP). An Iqcn knockout (Iqcn-/-) mouse model was generated by CRISPR-Cas9 technology to evaluate sperm motility and the ultrastructure of the flagellum. Hyperactivation and sperm fertilizing ability were assessed in a mouse model. Immunoprecipitation followed by liquid chromatography-mass spectrometry was used to detect IQCN-binding proteins. Immunofluorescence was used to validate the localization of IQCN-binding proteins. MAIN RESULTS AND THE ROLE OF CHANCE: Biallelic variants in IQCN (c.3913A>T and c.3040A>G; c.2453_2454del) were identified in our cohort of infertile men. The sperm from the affected individuals showed an irregular '9 + 2' structure of the flagellum, which resulted in abnormal CASA parameters. Similar phenotypes were observed in Iqcn-/- male mice. VSL, VCL, and VAP in the sperm of Iqcn-/- male mice were significantly lower than those in Iqcn+/+ male mice. Partial peripheral doublet microtubules (DMTs) and outer dense fibers (ODFs) were absent, or a chaotic arrangement of DMTs was observed in the principal piece and end piece of the sperm flagellum. Hyperactivation and IVF ability were impaired in Iqcn-/- male mice. In addition, we investigated the causes of motility defects and identified IQCN-binding proteins including CDC42 and the intraflagellar transport protein families that regulate flagellar assembly during spermiogenesis. LIMITATIONS, REASONS FOR CAUTION: More cases are needed to demonstrate the relation between IQCN variants and phenotypes. WIDER IMPLICATIONS OF THE FINDINGS: Our findings expand the genetic and phenotypic spectrum of IQCN variants in causing male infertility, providing a genetic marker for sperm motility deficiency and male infertility. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Natural Science Foundation of China (81974230 and 82202053), the Changsha Municipal Natural Science Foundation (kq2202072), the Hunan Provincial Natural Science Foundation (2022JJ40658), and the Scientific Research Foundation of Reproductive and Genetic Hospital of CITIC-Xiangya (YNXM-202114 and YNXM-202201). No conflicts of interest were declared. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Infertilidade Masculina , Espermatozoides , Animais , Humanos , Masculino , Camundongos , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Sêmen/metabolismo , Motilidade dos Espermatozoides/genética , Cauda do Espermatozoide/metabolismo , Espermatozoides/metabolismo , Espermatozoides/patologia
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