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1.
World J Stem Cells ; 16(3): 245-256, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38577237

RESUMO

Mesenchymal stem cells (MSCs) are stem/progenitor cells capable of self-renewal and differentiation into osteoblasts, chondrocytes and adipocytes. The transformation of multipotent MSCs to adipocytes mainly involves two subsequent steps from MSCs to preadipocytes and further preadipocytes into adipocytes, in which the process MSCs are precisely controlled to commit to the adipogenic lineage and then mature into adipocytes. Previous studies have shown that the master transcription factors C/enhancer-binding protein alpha and peroxisome proliferation activator receptor gamma play vital roles in adipogenesis. However, the mechanism underlying the adipogenic differentiation of MSCs is not fully understood. Here, the current knowledge of adipogenic differentiation in MSCs is reviewed, focusing on signaling pathways, noncoding RNAs and epigenetic effects on DNA methylation and acetylation during MSC differentiation. Finally, the relationship between maladipogenic differentiation and diseases is briefly discussed. We hope that this review can broaden and deepen our understanding of how MSCs turn into adipocytes.

2.
Gen Hosp Psychiatry ; 89: 1-7, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38579547

RESUMO

OBJECTIVE: This study was designed to examine the association between physical activity (PA) and depression among adult prescription opioid users. METHOD: Data of adults who recently took prescription opioids were collected from NHANES 2007-2018. Participants were divided into two groups according to whether PA in each domain was ≥600 MET-min/week. According to weekly activity frequency, recreational physical activity (RPA) was divided into inactivity, insufficient activity, weekend warrior (WW), and regular activity. PHQ-9 scores ≥10 were identified as depression. RESULTS: RPA of ≥600 MET-min/week was associated with a 40% (OR: 0.60, 95%CI: 0.38-0.96, P = 0.032) reduction in the risk of depression. Restricted Cubic Spline plots found a nonlinear dose-response relationship between RPA and depression (P = 0.045), and the turning point of depression risk was around 600 MET-min/week. There was no significant difference in the risk of depression between the WW and inactivity groups (OR: 0.65, 95%CI: 0.25-1.72, P = 0.382). The regular activity group had an 45% (OR: 0.55, 95%CI: 0.31-0.99, P = 0.046)lower risk for depression than the inactivity group. CONCLUSION: Only regular RPA is associated with a reduced risk of depression, and RPA showed a nonlinear dose-response relationship. The antidepressant effect of the WW is not significant.

3.
Respir Res ; 25(1): 160, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600524

RESUMO

BACKGROUND: No effective therapies for pulmonary fibrosis (PF) exist because of the unclear molecular pathogenesis and the lack of effective therapeutic targets. Zinc finger protein 451 (ZNF451), a transcriptional regulator, plays crucial roles in the pathogenesis of several diseases. However, its expression pattern and function in PF remain unknown. This study was designed to investigate the role of ZNF451 in the pathogenesis of lung fibrosis. METHODS: GEO dataset analysis, RT‒PCR, and immunoblot assays were used to examine the expression of ZNF451 in PF; ZNF451 knockout mice and ZNF451-overexpressing lentivirus were used to determine the importance of ZNF451 in PF progression; and migration assays, immunofluorescence staining, and RNA-seq analysis were used for mechanistic studies. RESULTS: ZNF451 is downregulated and negatively associated with disease severity in PF. Compared with wild-type (WT) mice, ZNF451 knockout mice exhibited much more serious PF changes. However, ZNF451 overexpression protects mice from BLM-induced pulmonary fibrosis. Mechanistically, ZNF451 downregulation triggers fibroblast activation by increasing the expression of PDGFB and subsequently activating PI3K/Akt signaling. CONCLUSION: These findings uncover a critical role of ZNF451 in PF progression and introduce a novel regulatory mechanism of ZNF451 in fibroblast activation. Our study suggests that ZNF451 serves as a potential therapeutic target for PF and that strategies aimed at increasing ZNF451 expression may be promising therapeutic approaches for PF.


Assuntos
Fibrose Pulmonar , Animais , Camundongos , Bleomicina/toxicidade , Fibroblastos/metabolismo , Pulmão/metabolismo , Camundongos Knockout , Fosfatidilinositol 3-Quinases/metabolismo , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , Transdução de Sinais
4.
Mol Plant Pathol ; 25(4): e13452, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619823

RESUMO

Phytophthora root and stem rot of soybean (Glycine max), caused by the oomycete Phytophthora sojae, is an extremely destructive disease worldwide. In this study, we identified GmEIL1, which encodes an ethylene-insensitive3 (EIN3) transcription factor. GmEIL1 was significantly induced following P. sojae infection of soybean plants. Compared to wild-type soybean plants, transgenic soybean plants overexpressing GmEIL1 showed enhanced resistance to P. sojae and GmEIL1-silenced RNA-interference lines showed more severe symptoms when infected with P. sojae. We screened for target genes of GmEIL1 and confirmed that GmEIL1 bound directly to the GmERF113 promoter and regulated GmERF113 expression. Moreover, GmEIL1 positively regulated the expression of the pathogenesis-related gene GmPR1. The GmEIL1-regulated defence response to P. sojae involved both ethylene biosynthesis and the ethylene signalling pathway. These findings suggest that the GmEIL1-GmERF113 module plays an important role in P. sojae resistance via the ethylene signalling pathway.


Assuntos
Fabaceae , Phytophthora , Fatores de Transcrição/genética , Soja/genética , Etilenos , Plantas Geneticamente Modificadas
5.
STAR Protoc ; 5(2): 103018, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38613778

RESUMO

The fatty acid-binding protein 5 (FABP5) is a key player in psoriasis development. Therefore, characterizing the expression profile of FABP5 in various cell types within both layers of psoriatic skin is important. Here, we present a protocol that describes steps for an imiquimod-induced psoriasis mouse model and preparation of epidermal and dermal single-cell suspensions. We then detail procedures to detect the FABP5 expression profile in skin keratinocytes and immune cells using intracellular flow cytometry staining. For complete details on the use and execution of this protocol, please refer to Hao et al.1.

6.
Int Med Case Rep J ; 17: 341-346, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646456

RESUMO

This study aimed to optimize bowel preparation efficacy for colonoscopy in elderly constipation patients. A 71-year-old patient with chronic constipation and a history of poor bowel preparation. To address these challenges, we implemented a personalized strategy combining of PEG administration and walking exercise. The PEG was administered according to a protocol, with intermittent exercise breaks of 10 minute. Bowel cleanliness was assessed using the Boston Bowel Preparation Scale (BBPS). Adverse reactions and tolerance were closely monitored throughout the intervention. The patient's BBPS score improved from 3 to 8 post-intervention. The exercise intervention was well-tolerated (rating I), and mild nausea was observed only after the first PEG dose. No severe adverse reactions occurred. Subsequent Follow-up revealed symptom relief. The personalized approach combining (PEG and exercise intervention) successfully improved bowel preparation quality in the elderly constipation patient undergoing colonoscopy. This approach considers age-related changes in gastrointestinal function and activity level, offering an effective strategy to improve patient tolerance and reduce adverse reactions during bowel preparation. The findings underscore the importance of tailoring interventions for elderly constipation patients to optimize the colonoscopy experience.

7.
J Nanobiotechnology ; 22(1): 202, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658952

RESUMO

Multi-modal combination therapy is regarded as a promising approach to cancer treatment. Combining chemotherapy and phototherapy is an essential multi-modal combination therapy endeavor. Ivermectin (IVM) is a potent antiparasitic agent identified as having potential antitumor properties. However, the fact that it induces protective autophagy while killing tumor cells poses a challenge to its further application. IR780 iodide (IR780) is a near-infrared (NIR) dye with outstanding photothermal therapy (PTT) and photodynamic therapy (PDT) effects. However, the hydrophobicity, instability, and low tumor uptake of IR780 limit its clinical applications. Here, we have structurally modified IR780 with hydroxychloroquine, an autophagy inhibitor, to synthesize a novel compound H780. H780 and IVM can form H780-IVM nanoparticles (H-I NPs) via self-assembly. Using hyaluronic acid (HA) to modify the H-I NPs, a novel nano-delivery system HA/H780-IVM nanoparticles (HA/H-I NPs) was synthesized for chemotherapy-phototherapy of colorectal cancer (CRC). Under NIR laser irradiation, HA/H-I NPs effectively overcame the limitations of IR780 and IVM and exhibited potent cytotoxicity. In vitro and in vivo experiment results showed that HA/H-I NPs exhibited excellent anti-CRC effects. Therefore, our study provides a novel strategy for CRC treatment that could enhance chemo-phototherapy by modulating autophagy.


Assuntos
Autofagia , Neoplasias Colorretais , Reposicionamento de Medicamentos , Ivermectina , Nanopartículas , Autofagia/efeitos dos fármacos , Animais , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/terapia , Humanos , Camundongos , Nanopartículas/química , Ivermectina/farmacologia , Ivermectina/química , Linhagem Celular Tumoral , Indóis/química , Indóis/farmacologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Fotoquimioterapia/métodos , Antineoplásicos/farmacologia , Antineoplásicos/química , Fototerapia/métodos , Ácido Hialurônico/química , Hidroxicloroquina/farmacologia , Hidroxicloroquina/química , Terapia Fototérmica/métodos
8.
Medicine (Baltimore) ; 103(15): e37838, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608046

RESUMO

BACKGROUND: The effects of vitamin C supplementation on patients with septic shock remain controversial. We aimed to evaluate the effects of different vitamin C dosages on norepinephrine (NE) synthesis in adult patients with septic shock. METHODS: A total of 58 patients with septic shock admitted to our intensive care unit (ICU) between July 2021 and December 2022 were included. Patients were randomly divided into 3 groups: high-dose vitamin C (150 mg/kg/d, group A), low-dose vitamin C (50 mg/kg/d, group B), and placebo (group C). NE synthesis-related indicators (dopamine-ß-hydroxylase [DßH], tyrosine hydroxylase [TH], tetrahydrobiopterin [BH4], and dopamine [DA]), plasma NE, and vitamin C levels were measured every 24 hours and analyzed. All-cause mortality within 28 days and other clinical outcomes (including Acute Physiology and Chronic Health Evaluation [APACHE], Sequential Organ Failure Assessment [SOFA], and Multiple-Organ Dysfunction Syndrome [MODS] scores) were compared. RESULTS: Changes in TH, BH4, and DßH levels at 96 hours in groups A and B were greater than those in group C. These differences became more pronounced over the course of the intravenous vitamin C administration. Significant differences between groups A and C were detected at 96-hours TH, 72-hours BH4, 96-hours BH4, 96-hours DA, and DßH levels every 24 hours. The 96-hours TH, 96-hours BH4, and 48-hours DßH in group B were significantly higher than those in group C. The NE levels every 24 hours in groups A and B were higher than those in group C, group A and group C had a statistically significant difference. The 96-hours exogenous NE dosage in groups A and B was significantly lower than that in group C. No significant reductions in APACHE, SOFA, or MODS scores were observed in the vitamin C group, including the duration of ICU stay and mechanical ventilation. The 28-days mortality was lower in groups A and B than in group C (0%, 10%, and 16.67%, P = .187), but the difference was not significant. CONCLUSION: For patients with septic shock, treatment with vitamin C significantly increased TH, BH4, and DßH levels and reduced the exogenous NE dosage, but did not significantly improve clinical outcomes.


Assuntos
Antineoplásicos , Choque Séptico , Adulto , Humanos , Norepinefrina , Choque Séptico/tratamento farmacológico , Dopamina , Estudos Prospectivos , Vitaminas/uso terapêutico , Ácido Ascórbico/uso terapêutico
10.
J Adv Res ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38494073

RESUMO

Non-alcoholic steatohepatitis (NASH), an emerging global healthcare problem, has become the leading cause of liver transplantation in recent decades. No effective therapies in the clinic have been proven due to the incomplete understanding of the pathogenesis of NASH, and further studies are expected to continue to delve into the mechanisms of NASH. Extracellular vesicles (EVs), which are small lipid membrane vesicles carrying proteins, microRNAs and other molecules, have been identified to play a vital role in cell-to-cell communication and are involved in the development and progression of various diseases. In recent years, there has been increasing interest in the role of EVs in NASH. Many studies have revealed that EVs mediate important pathological processes in NASH, and the role of EVs in NASH is distinct and variable depending on their origin cells and target cells. This review outlines the emerging mechanisms of EVs in the development of NASH and the preclinical evidence related to stem cell-derived EVs as a potential therapeutic strategy for NASH. Moreover, possible strategies involving EVs as clinical diagnostic, staging and prognostic biomarkers for NASH are summarized.

11.
Front Pharmacol ; 15: 1364135, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510648

RESUMO

The rapid evolution of gene editing technology has markedly improved the outlook for treating genetic diseases. Base editing, recognized as an exceptionally precise genetic modification tool, is emerging as a focus in the realm of genetic disease therapy. We provide a comprehensive overview of the fundamental principles and delivery methods of cytosine base editors (CBE), adenine base editors (ABE), and RNA base editors, with a particular focus on their applications and recent research advances in the treatment of genetic diseases. We have also explored the potential challenges faced by base editing technology in treatment, including aspects such as targeting specificity, safety, and efficacy, and have enumerated a series of possible solutions to propel the clinical translation of base editing technology. In conclusion, this article not only underscores the present state of base editing technology but also envisions its tremendous potential in the future, providing a novel perspective on the treatment of genetic diseases. It underscores the vast potential of base editing technology in the realm of genetic medicine, providing support for the progression of gene medicine and the development of innovative approaches to genetic disease therapy.

12.
Cell Tissue Res ; 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38492000

RESUMO

Dentin is a permeable and complex tubular composite formed by the mineralization of predentin that mineralization and repair are of considerable clinical interest during dentin homeostasis. The role of Vdr, a receptor of vitamin D, in dentin homeostasis remains unexplored. The aim of the present study was to assess the impact of Vdr on predentin mineralization and dental repair. Vdr-knockout (Vdr-/-) mice models were constructed; histology and immunohistochemistry analyses were conducted for both WT and Vdr-/- mice. The finding revealed a thicker predentin in Vdr-/- mice, characterized by higher expression of biglycan and decorin. A dental injury model was employed to observe tertiary dentin formation in Vdr-/- mice with dental injuries. Results showed that tertiary dentin was harder to form in Vdr-/- mice with dental injury. Over time, heightened pulp invasion was observed at the injury site in Vdr-/- mice. Expression of biglycan and decorin was reduced in the predentin at the injury site in the Vdr-/- mice by immunohistochemistry. Taken together, our results imply that Vdr plays a regulatory role in predentin mineralization and tertiary dentin formation during dentin homeostasis.

13.
Medicine (Baltimore) ; 103(12): e37509, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38518033

RESUMO

Xining is located at the eastern edge of the Qinghai-Tibet Plateau, with an average altitude of >7000 feet (>2000 m). Nalbuphine is a kappa-opioid receptor agonist that can provide analgesia with fewer side effects than other opioid analgesics. This study aimed to evaluate pain control, side effects, and neonatal outcomes from combining nalbuphine with sufentanil and ropivacaine in 600 women during epidural anesthesia while giving birth at a high altitude in Xining, China. A total of 600 parturients receiving epidural labor analgesia were randomly divided into 2 groups, each group 300 parturients. The nalbuphine group received nalbuphine, sufentanil, and ropivacain, the control group only received sufentanil and ropivacain. The analgesic effect was evaluated through the Visual Analogue Scale scores. Neonatal outcomes were mainly evaluated through the Apgar Scores. Compared to the control group, the nalbuphine group showed lower Visual Analogue Scale scores at all time points after analgesia (P < .05). In comparison with the control group, parturients in the nalbuphine group showed lower incidence rates of fever at delivery, 24-hour postpartum bleeding, and pruritus (P < .05). However, between the 2 groups, there were no statistically significant differences in the remaining maternal and infant outcomes and neonatal outcomes (P > .05). Moreover, no adverse effects on neonatal outcomes were observed. The findings from this study support findings from previous studies that nalbuphine provided safe epidural analgesia without significant side effects for the mother and infant, and showed both safety and efficacy when used during labor at high altitude.


Assuntos
Analgesia Epidural , Analgesia Obstétrica , Nalbufina , Feminino , Humanos , Recém-Nascido , Gravidez , Altitude , Analgesia Epidural/efeitos adversos , Analgesia Obstétrica/efeitos adversos , Analgésicos/efeitos adversos , Analgésicos Opioides/efeitos adversos , Anestésicos Locais , Nalbufina/efeitos adversos , Dor/etiologia , Sufentanil/uso terapêutico
14.
Int J Biol Macromol ; 264(Pt 2): 130692, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460646

RESUMO

In this study, a multi-functional packaging film was fabricated, utilizing the natural polysaccharide chitosan (CS) as the base material, integrating natural blueberry anthocyanin (AN) as pH-responsive indicator, and reinforced with cellulose nanocrystals (CNCs). The implications of addition levels of CNCs on the characteristics of the films were systematically investigated, resulting in that CS-AN-CNCs 9 % film exhibited optimal performance. Specifically, the film showed a substantial enhancement in maximum tensile strength from 15 MPa to 35 MPa; On the other hand, the swelling degree properties, the oxygen permeability and water vapor permeability decreased from 159.2 % to 92.0 %, from 51.7 g/(m2d) to 12.2 g/(m2d), from 31.6 × 10-12 g/(m·s·Pa) to 1.6 × 10-12 g/(m·s·Pa), respectively. Moreover, the CS-AN-CNCs 9 % film exhibited antioxidant, antibacterial, coupled with a color metrically responsive to pH variations, displaying great potential in indicating the shrimp freshness and delaying spoilage. Another notable advantage of the-prepared packaging material lies in its completely biodegradability, therefore meeting the requirement of environmental protection. Therefore, the prepared CS-AN-CNCs film as an intelligent packaging solution with potential applications in food preservation and freshness monitoring applications.


Assuntos
Quitosana , Nanopartículas , Animais , Antocianinas , Celulose , Embalagem de Medicamentos , Crustáceos , Embalagem de Alimentos , Concentração de Íons de Hidrogênio
15.
Int J Cancer ; 154(12): 2031-2042, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38500385

RESUMO

Tumor-associated myeloid cells (TAMCs) play a crucial role in orchestrating the dynamics of the tumor immune microenvironment. This heterogeneous population encompasses myeloid-derived suppressor cells, tumor-associated macrophages and dendritic cells, all of which contribute to the establishment of an immunosuppressive milieu that fosters tumor progression. Tumor-derived exosomes (TEXs), small extracellular vesicles secreted by tumor cells, have emerged as central mediators in intercellular communication within the tumor microenvironment. In this comprehensive review, we explore the intricate mechanisms through which TEXs modulate immune-suppressive effects on TAMCs and their profound implications in cancer progression. We delve into the multifaceted ways in which TEXs influence TAMC functions, subsequently affecting tumor immune evasion. Furthermore, we elucidate various therapeutic strategies aimed at targeting TEX-mediated immune suppression, with the ultimate goal of bolstering antitumor immunity.


Assuntos
Exossomos , Células Supressoras Mieloides , Neoplasias , Humanos , Exossomos/patologia , Neoplasias/patologia , Terapia de Imunossupressão , Células Mieloides , Microambiente Tumoral
16.
Mol Cancer ; 23(1): 54, 2024 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486218

RESUMO

BACKGROUND: Phosphoinositide 3-kinases (PI3Ks) are critical regulators of diverse cellular functions and have emerged as promising targets in cancer therapy. Despite significant progress, existing PI3K inhibitors encounter various challenges such as suboptimal bioavailability, potential off-target effects, restricted therapeutic indices, and cancer-acquired resistance. Hence, novel inhibitors that overcome some of these challenges are needed. Here, we describe the characterization of KTC1101, a novel pan-PI3K inhibitor that simultaneously targets tumor cell proliferation and the tumor microenvironment. Our studies demonstrate that KTC1101 significantly increases the anti-PD-1 efficacy in multiple pre-clinical mouse models. METHODS: KTC1101 was synthesized and characterized employing chemical synthesis, molecular modeling, Nuclear Magnetic Resonance (NMR), and mass spectrometry. Its target specificity was confirmed through the kinase assay, JFCR39 COMPARE analysis, and RNA-Seq analysis. Metabolic stability was verified via liver microsome and plasma assays, pharmacokinetics determined by LC-MS/MS, and safety profile established through acute toxicity assays to determine the LD50. The antiproliferative effects of KTC1101 were evaluated in a panel of cancer cell lines and further validated in diverse BALB/c nude mouse xenograft, NSG mouse xenograft and syngeneic mouse models. The KTC1101 treatment effect on the immune response was assessed through comprehensive RNA-Seq, flow cytometry, and immunohistochemistry, with molecular pathways investigated via Western blot, ELISA, and qRT-PCR. RESULTS: KTC1101 demonstrated strong inhibition of cancer cell growth in vitro and significantly impeded tumor progression in vivo. It effectively modulated the Tumor Microenvironment (TME), characterized by increased infiltration of CD8+ T cells and innate immune cells. An intermittent dosing regimen of KTC1101 enhanced these effects. Notably, KTC1101 synergized with anti-PD-1 therapy, significantly boosting antitumor immunity and extending survival in preclinical models. CONCLUSION: KTC1101's dual mechanism of action-directly inhibiting tumor cell growth and dynamically enhancing the immune response- represents a significant advancement in cancer treatment strategies. These findings support incorporating KTC1101 into future oncologic regimens to improve the efficacy of immunotherapy combinations.


Assuntos
Linfócitos T CD8-Positivos , Fosfatidilinositol 3-Quinases , Humanos , Animais , Camundongos , Cromatografia Líquida , Espectrometria de Massas em Tandem , Imunoterapia
17.
J Am Chem Soc ; 146(12): 8335-8342, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38487863

RESUMO

The inherent inertness and striking physicochemical similarities of krypton and xenon pose significant challenges to their separation. Reported herein is the efficient xenon capture and xenon/krypton adsorptive separation by transition metal-free zeolites under ambient conditions. The polarized environment of zeolite, denoted as local polarity, can be tuned by changing the topology, framework composition, and counter-cations, which in turn correlates with the guest-host interaction and separation performance. Chabazite zeolite with a framework Si/Al ratio of 2.5 and Ca2+ as the counter-cations, namely, Ca-CHA-2.5, is developed as a state-of-the-art zeolite adsorbent, showing remarkable performance, i.e., high dynamic xenon uptake, high xenon/krypton separation selectivity, and good recyclability, in the adsorptive separation of the xenon/krypton mixture. Grand Canonical Monte Carlo simulation reveals that extraframework Ca2+ cations act as the primary binding sites for xenon and can stabilize xenon molecules together with the chabazite framework, whereas krypton molecules are stabilized by weak guest-host interaction with the zeolite framework.

18.
Bioconjug Chem ; 35(4): 465-471, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38499390

RESUMO

A versatile chemo-enzymatic tool to site-specifically modify native (nonengineered) antibodies is using transglutaminase (TGase, E.C. 2.3.2.13). With various amines as cosubstrates, this enzyme converts the unsubstituted side chain amide of glutamine (Gln or Q) in peptides and proteins into substituted amides (i.e., conjugates). A pleasant surprise is that only a single conserved glutamine (Gln295) in the Fc region of IgG is modified by microbial TGase (mTGase, EC 2.3.2.13), thereby providing a highly specific and generally applicable conjugation method. However, prior to the transamidation (access to the glutamine residue by mTGase), the steric hindrance from the nearby conserved N-glycan (Asn297 in IgG1) must be reduced. In previous approaches, amidase (PNGase F, EC 3.5.1.52) was used to completely remove the N-glycan. However, PNGase F also converts a net neutral asparagine (Asn297) to a negatively charged aspartic acid (Asp297). This charge alteration may markedly change the structure, function, and immunogenicity of an IgG antibody. In contrast, in our new method presented herein, the N-glycan is trimmed by an endoglycosidase (EndoS2, EC 3.2.1.96), hence retaining both the core N-acetylglucosamine (GlcNAc) moiety and the neutral asparaginyl amide. The trimmed glycan also reduces or abolishes Fc receptor-mediated functions, which results in better imaging agents by decreasing nonspecific binding to other cells (e.g., immune cells). Moreover, the remaining core glycan allows further derivatization such as glycan remodeling and dual conjugation. Practical and robust, our method generates conjugates in near quantitative yields, and both enzymes are commercially available.


Assuntos
Glutamina , Glicosídeo Hidrolases , Glutamina/química , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase , Transglutaminases/metabolismo , Imunoglobulina G/química , Polissacarídeos/química , Amidas
19.
Mar Life Sci Technol ; 6(1): 1-14, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38433969

RESUMO

The electric catfish (Malapterurus electricus), belonging to the family Malapteruridae, order Siluriformes (Actinopterygii: Ostariophysi), is one of the six branches that has independently evolved electrical organs. We assembled a 796.75 Mb M. electricus genome and anchored 88.72% sequences into 28 chromosomes. Gene family analysis revealed 295 expanded gene families that were enriched on functions related to glutamate receptors. Convergent evolutionary analyses of electric organs among different lineage of electric fishes further revealed that the coding gene of rho guanine nucleotide exchange factor 4-like (arhgef4), which is associated with G-protein coupled receptor (GPCR) signaling pathway, underwent adaptive parallel evolution. Gene identification suggests visual degradation in catfishes, and an important role for taste in environmental adaptation. Our findings fill in the genomic data for a branch of electric fish and provide a relevant genetic basis for the adaptive evolution of Siluriformes. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-023-00197-8.

20.
J Opt Soc Am A Opt Image Sci Vis ; 41(2): 241-251, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437336

RESUMO

A recently proposed method is upgraded to convert two amplitude phase modulation systems (APMSs) to pure phase elements (PPEs), for generating the stable propagation Bessel beam and the axial multifoci beam, respectively. Phase functions of the PPEs are presented analytically. Numerical simulations by the complete Rayleigh-Sommerfeld method demonstrate that the converted PPE has implemented the same optical functionalities as the corresponding APMS, in either the longitudinal or the transverse direction. Compared with the traditional APMS, the converted PPE possesses many advantages such as fabrication process simplification, system complexity reduction, production cost conservation, alignment error avoidance, and experimental precision enhancement. These inherent advantages position the PPE as an ideal choice and driving force behind further advancements in optical system technology.

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