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1.
Blood Adv ; 8(7): 1667-1682, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38286463

RESUMO

ABSTRACT: Congenital neutropenia (CN) is a genetic disorder characterized by persistent or intermittent low peripheral neutrophil counts, thus increasing susceptibility to bacterial and fungal infections. Various forms of CN, caused by distinct genetic mutations, exhibit differential responses to granulocyte colony-stimulating factor (G-CSF) therapy, with the underlying mechanisms not fully understood. This study presents an in-depth comparative analysis of clinical and immunological features in 5 CN patient groups (severe congenital neutropenia [SCN]1, SCN3, cyclic neutropenia [CyN], warts, hypogammaglobulinaemia, infections and myelokathexis [WHIM], and Shwachman-Bodian-Diamond Syndrome [SBDS]) associated with mutations in ELANE, HAX1, CXCR4, and SBDS genes. Our analysis led to the identification of 11 novel mutations in ELANE and 1 each in HAX1, CXCR4, and G6PC3 genes. Investigating bone marrow (BM) granulopoiesis and blood absolute neutrophil count after G-CSF treatment, we found that SCN1 and SCN3 presented with severe early-stage disruption between the promyelocyte and myelocyte, leading to a poor response to G-CSF. In contrast, CyN, affected at the late polymorphonuclear stage of neutrophil development, showed a strong G-CSF response. WHIM, displaying normal neutrophil development, responded robustly to G-CSF, whereas SBDS, with moderate disruption from the early myeloblast stage, exhibited a moderate response. Notably, SCN1 uniquely impeded neutrophil development, whereas SCN3, CyN, WHIM, and SBDS also affected eosinophils and basophils. In addition, SCN1, SCN3, and CyN presented with elevated serum immunoglobulins, increased BM plasma cells, and higher A Proliferation-Inducing Ligand levels. Our study reveals a strong correlation between the stage and severity of granulocyte development disruption and the efficacy of G-CSF therapy.


Assuntos
Síndrome Congênita de Insuficiência da Medula Óssea , Eosinófilos , Fator Estimulador de Colônias de Granulócitos , Neutropenia/congênito , Humanos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Mutação , Proteínas Adaptadoras de Transdução de Sinal
2.
Biol Trace Elem Res ; 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38103107

RESUMO

Peony seed is an excellent oil crop, and peony seed oil is rich in unsaturated fatty acids needed by the human body. In this study, inductively coupled plasma mass spectrometry (ICP-MS), fingerprint, and chemometrics, the correlation between the content of inorganic elements in oil peony seeds, their origins, and varieties were investigated. Meanwhile, estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI), and carcinogenic risks (CR) were combined to evaluate the comprehensive health risks of heavy metals in peony seed oil. The results showed that the difference in the content of inorganic elements could identify the varieties of oil peony seeds. Sr, K, Ca, V, Al, Fe, Cu, Ba, As, Ga, Co, and Rb were the characteristic inorganic elements that played a role in identification. In addition, The THQs and HIs (< 1) for non-carcinogenic elements indicated no risk. The CRs indicated that the carcinogenic harm was negligible. The study concluded that three varieties of peony seed oil would not pose any health hazard. It provided an effective comprehensive method for the identification of oil peony seeds and predicted the potential health risks of edible peony seed oil, providing a reference for the development and consumption of peony seed oil food.

3.
J Agric Food Chem ; 71(33): 12609-12617, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37566884

RESUMO

Dry/reimmersed storage is often used in the transportation of live scallops. In this study, tandem mass tag (TMT)-labeled protein omics were used to quantitatively analyze the protein changes in scallops during dry/reimmersed stress. The results showed that during dry storage, scallops maintained cellular redox homeostasis through the upregulation of SCO1-like protein and thioredoxin domain-containing protein and reduced organic acids from the ATP synthetic process by the downregulation of NADH dehydrogenase, thereby reducing the damage caused during dry storage. During reimmersed storage, mitochondrial proteins underwent very sensitive changes. By upregulating aerobic respiration-related proteins (including proteins involved in glucose phosphate metabolism, glyceraldehyde 3-phosphate metabolism, etc.), the ATP synthesis ability was improved. However, the damage to the mitochondrial structure by dry storage could not be completely recovered, even by reimmersion. This included some apoptosis-related proteins that were obviously upregulated. In summary, compared with ATP-related indexes, mitochondria can respond more sensitively to dry storage stress.


Assuntos
Pectinidae , Proteômica , Animais , Pectinidae/metabolismo , Trifosfato de Adenosina/metabolismo , Mitocôndrias/metabolismo
4.
BMJ Open ; 12(10): e064216, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36223961

RESUMO

INTRODUCTION: Rituximab (RTX) effectively prevents relapses in patients with complicated steroid-sensitive nephrotic syndrome (SSNS). The 1-year relapse-free survival rate is approximately 30% in children after the first episode of SSNS treated with standardised corticosteroids. Whether the benefits of RTX extend to the first relapse are unknown. The efficacy and safety of RTX in the first episode of paediatric idiopathic nephrotic syndrome (RTXFIRPedINS) trial (NCT04783675) will assess its effect on the risk of subsequent relapse. METHODS AND ANALYSIS: RTXFIRPedINS is an open-label, single-arm, multicentre trial targeting patients aged 1-18 years with a first episode of SSNS. All patients will receive standardised corticosteroid treatment for 12 weeks. A sample size of 44 patients provides 80% power to detect a 20% increase in the 1-year relapse-free rate, assuming a dropout rate of 10%. After obtaining informed consent and screening, eligible patients will be treated with a single intravenous infusion of 375 mg/m2 RTX within 1 week after achieving remission. Trimethoprim-sulfamethoxazole will be administered for 3 months after RTX administration to prevent Pneumocystis carinii infection. The follow-up period will be 1 year. The primary outcome is the 1-year relapse-free survival rate after RTX infusion. The secondary study outcomes are the number of days from the infusion of RTX to the occurrence of the first relapse, 6-month relapse-free survival rate, the B cell recovery time and treatment-related adverse events. Immunological factors will be studied as predictors of response. ETHICS AND DISSEMINATION: This trial was approved by the Ethics Committee of the Children's Hospital of Fudan University and seven local ethics committees. We will publish our study results in peer-reviewed journals and present them at international scientific meetings. TRIAL REGISTRATION NUMBER: NCT04783675.


Assuntos
Síndrome Nefrótica , Rituximab , Criança , Humanos , Fatores Imunológicos/efeitos adversos , Estudos Multicêntricos como Assunto , Recidiva Local de Neoplasia/tratamento farmacológico , Síndrome Nefrótica/tratamento farmacológico , Recidiva , Rituximab/efeitos adversos , Esteroides/uso terapêutico , Resultado do Tratamento , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
5.
Proc Natl Acad Sci U S A ; 119(36): e2205629119, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36037365

RESUMO

Elimination of autoreactive developing B cells is an important mechanism to prevent autoantibody production. However, how B cell receptor (BCR) signaling triggers apoptosis of immature B cells remains poorly understood. We show that BCR stimulation up-regulates the expression of the lysosomal-associated transmembrane protein 5 (LAPTM5), which in turn triggers apoptosis of immature B cells through two pathways. LAPTM5 causes BCR internalization, resulting in decreased phosphorylation of SYK and ERK. In addition, LAPTM5 targets the E3 ubiquitin ligase WWP2 for lysosomal degradation, resulting in the accumulation of its substrate PTEN. Elevated PTEN levels suppress AKT phosphorylation, leading to increased FOXO1 expression and up-regulation of the cell cycle inhibitor p27Kip1 and the proapoptotic molecule BIM. In vivo, LAPTM5 is involved in the elimination of autoreactive B cells and its deficiency exacerbates autoantibody production. Our results reveal a previously unidentified mechanism that contributes to immature B cell apoptosis and B cell tolerance.


Assuntos
Apoptose , Tolerância Imunológica , Proteínas de Membrana , Células Precursoras de Linfócitos B , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Proteína Forkhead Box O1/metabolismo , Humanos , Lisossomos/metabolismo , Proteínas de Membrana/genética , PTEN Fosfo-Hidrolase/metabolismo , Células Precursoras de Linfócitos B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
6.
JCI Insight ; 6(19)2021 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-34622798

RESUMO

Hypomorphic RAG1 or RAG2 mutations cause primary immunodeficiencies and can lead to autoimmunity, but the underlying mechanisms are elusive. We report here a patient carrying a c.116+2T>G homozygous splice site mutation in the first intron of RAG1, which led to aberrant splicing and greatly reduced RAG1 protein expression. B cell development was blocked at both the pro-B to pre-B transition and the pre-B to immature B cell differentiation step. The patient B cells had reduced B cell receptor repertoire diversity and decreased complementarity determining region 3 lengths. Despite B cell lymphopenia, the patient had abundant plasma cells in the BM and produced large quantities of IgM and IgG Abs, including autoantibodies. The proportion of naive B cells was reduced while the frequency of IgD-CD27- double-negative (DN) B cells, which quickly differentiated into Ab-secreting plasma cells upon stimulation, was greatly increased. Immune phenotype analysis of 52 patients with primary immunodeficiency revealed a strong association of the increased proportion of DN B and memory B cells with decreased number and proportion of naive B cells. These results suggest that the lymphopenic environment triggered naive B cell differentiation into DN B and memory B cells, leading to increased Ab production.


Assuntos
Autoanticorpos/imunologia , Doenças Autoimunes/genética , Linfócitos B/imunologia , Granuloma/genética , Proteínas de Homeodomínio/genética , Síndromes de Imunodeficiência/genética , Linfopoese/genética , Receptores de Antígenos de Linfócitos B/imunologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/terapia , Criança , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Evolução Fatal , Granuloma/imunologia , Granuloma/terapia , Proteínas de Homeodomínio/metabolismo , Homozigoto , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Síndromes de Imunodeficiência/imunologia , Síndromes de Imunodeficiência/terapia , Memória Imunológica/imunologia , Linfopenia/genética , Linfopenia/imunologia , Linfopoese/imunologia , Masculino , Plasmócitos/imunologia , Sítios de Splice de RNA/genética , Recombinação V(D)J/genética
7.
Ann Palliat Med ; 10(6): 6669-6677, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34154339

RESUMO

BACKGROUND: Drug treatment is the main form of management for patient with gastroesophageal reflux disease (GERD). However, long-term medication can increase the psychological burden of patients. Furthermore, in some patients, standardized drug treatments do not effectively control their condition. Traditional anti-reflux surgery has a low degree of acceptance due to its trauma and many associated complications. In contrast, endoscopic minimally invasive surgery is preferable. This study explored the effects of endoscopic treatment of cardia diseases on GERD. METHODS: A retrospective analysis was conducted on 106 patients with cardia disease (including cardia polyp, precancerous lesion, and early cardia cancer) and reflux esophagitis (RE). Patients underwent endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD), and the rates of complete resection, postoperative complications, and postoperative reflux were assessed. RESULTS: Among the 106 lesions, 104 lesions were completely resected, and 2 early cancers were cured. No delayed hemorrhage was detected in any of the cases. The GERD-HRQL (gastroesophageal reflux disease-health related quality of life) and GERD-Q (gastroesophageal reflux disease-questionnaires) scores decreased significantly at 3 and 6 months post-operation (P<0.001). Furthermore, the RE grade was significantly different before and after the operation (P<0.001). The basic cure rate at 3 and 6 months after the operation was 83.96% and 84.91%, respectively, and the significant remission rate was 10.38% and 8.49%, respectively. CONCLUSIONS: Endoscopic treatment of cardia conditions is advantageous due to low levels of trauma, higher complete resection rates, and fewer complications. Moreover, the fibrous scar generated after endoscopic treatment forms an anti-reflux barrier, which can alleviate or even cure RE to a certain extent. This may represent a promising method for the clinical treatment of GERD.


Assuntos
Cárdia , Refluxo Gastroesofágico , Cárdia/cirurgia , Endoscopia , Humanos , Qualidade de Vida , Estudos Retrospectivos
8.
Exp Anim ; 70(1): 45-53, 2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32921697

RESUMO

This study was to verify the effects of chitosan oligosaccharides (COS) on intestinal integrity, oxidative status, and inflammatory response in a heat-stressed rat model. A total of 24 male Sprague Dawley rats were randomly divided into 3 treatment: CON, the control group; HS, the heat stress group; HSC, the heat stress group with 200 mg/kg COS. Rats in the HS and HSC group exposed to a cyclical heat stress for 7 consecutive days. The CON and HS group provided basal diet, and the HSC group provided the same diet with 200 mg/kg COS. Compared with the HS group, rats in the HSC group had lower serum diamine oxidase and D-lactate acid level, higher villus height of jejunum and ileum, lower malondialdehyde (MDA) content in duodenum, jejunum, and ileum mucosa, higher glutathione peroxidase (GSH-Px), catalase (CAT) and total antioxidant capacity (T-AOC) activity in duodenum mucosa, higher T-AOC activity in jejunum mucosa, and higher glutathione (GSH) level in ileum mucosa. Compared with the HS group, rats in the HSC group had higher interleukin-10 (IL-10) level, but lower tumor necrosis factor-α (TNF-α) level in duodenum, jejunum, and ileum mucosa. These results indicated that COS may alleviate intestinal damage under heat stress condition, probably by modulating intestinal inflammatory response and oxidative status.


Assuntos
Quitosana/farmacologia , Resposta ao Choque Térmico/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Oligossacarídeos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Administração Oral , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Quitosana/administração & dosagem , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Inflamação , Interleucina-10/metabolismo , Mucosa Intestinal/patologia , Masculino , Malondialdeído/metabolismo , Modelos Animais , Oligossacarídeos/administração & dosagem , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
9.
Poult Sci ; 99(12): 6745-6752, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33248590

RESUMO

The purpose of this study was to evaluate the effects of chitosan oligosaccharides (COS) on intestinal permeability, morphology, antioxidant status, and inflammatory response in heat-stressed broilers. A total of 108 thirty-five-day-old Chinese yellow-feather broilers (body weight 470.31 ± 13.15 g) were randomly allocated to 3 dietary treatments as follows: CON group, basal diet and raised under normal temperature (24°C); HS group, basal diet and raised under cycle heat stress (34°C from 10:00-18:00 and 24°C for the rest time); HSC group, basal diet with 200 mg/kg COS supplementation and raised under cycle heat stress. Each treatment had 6 replication pens and 6 broilers per pen. Compared with the CON group, heat stress decreased (P < 0.05) the relative weight of duodenum and jejunum; the relative length and villus height (VH) of duodenum, jejunum, and ileum; the ileum VH to crypt depth ratio; duodenum mucosal catalase (CAT) activity; and jejunum mucosal glutathione peroxidase (GSH-Px) and CAT activity, whereas it increased (P < 0.05) serum diamine oxidase (DAO) activity and D-lactate acid (D-LA) content, duodenum and jejunum mucosal malondialdehyde (MDA) and interleukin-1ß (IL-1ß) content, and ileum mucosal tumor necrosis factor-α content. Compared to the HS group, dietary COS supplementation increased (P < 0.05) the relative length of duodenum, jejunum, and ileum; the VH of jejunum and ileum; and duodenum and jejunum mucosal GSH-Px activity, whereas it decreased (P < 0.05) serum DAO activity and D-LA concentration and duodenum and jejunum mucosal MDA and IL-1ß content. These results suggested that dietary COS supplementation had beneficial effects on intestinal morphology by increasing jejunum and ileum VH; permeability by decreasing serum DAO activity and D-LA content; antioxidant capacity by decreasing duodenum and jejunum mucosal MDA content and by increasing duodenum and jejunum GSH-Px activity; and inflammatory response by decreasing duodenum and jejunum mucosal IL-1ß content.


Assuntos
Galinhas , Quitosana , Suplementos Nutricionais , Estresse Oxidativo , Ração Animal/análise , Animais , Quitosana/farmacologia , Dieta/veterinária , Carboidratos da Dieta/farmacologia , Plumas , Resposta ao Choque Térmico , Oligossacarídeos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Distribuição Aleatória
10.
Hum Reprod ; 31(12): 2723-2729, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27664218

RESUMO

STUDY QUESTION: Does autologous transplantation of menstrual blood-derived stromal cells (menSCs) regenerate endometrium to support pregnancy in patients with severe Asherman's syndrome (AS)? SUMMARY ANSWER: Autologous menSCs transplantation significantly increases endometrial thickness (ET) for women with severe AS. WHAT IS KNOWN ALREADY: AS is a major cause of secondary infertility in women. Cell transplantation has been tried in a few clinical cases with encouraging results. STUDY DESIGN, SIZE, DURATION: In this experimental, non-controlled and prospective 3-year clinical study involving seven patients with AS, autologous menSCs were isolated and cultured from menstrual blood of each patient within ~2 weeks and then transplanted back into their uterus. Endometrial growth and pregnancy were assessed after cell therapy. PARTICIPANTS/MATERIALS, SETTING, METHOD: Infertile women, aged 20-40 years, diagnosed with severe AS (Grade III-V) by hysteroscopy and with menstrual fluid were recruited at the Shengjing Hospital affiliated to China Medical University. Autologous menSCs transplantation was conducted followed by HRT. Endometrial thickness was monitored with frozen embryo transfer (FET) as needed. MAIN RESULTS AND THE ROLE OF CHANCE: We successfully cultured menSCs from seven patients and transferred the autologous cells back to their uterus. Our results showed that the ET was significantly (P = 0.0002) increased to 7 mm in five women, which ensured embryo implantation. Four patients underwent FET and two of them conceived successfully. One patient had spontaneous pregnancy after second menSCs transplantation. LIMITATIONS, REASONS FOR CAUTION: Limited sample size, lack of rigorous controls or knowledge of underlying mechanism. WIDER IMPLICATIONS OF THE FINDINGS: Autologous menSCs transplantation is a potential option for treating women with severe AS. STUDY FUNDING/COMPETING INTERESTS: This study was supported by Liaoning Provincial Science and Technology Program. The sponsor and authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER: Registered in the Chinese Clinical Trial Registry (ChiCTR-ONB-15007464).


Assuntos
Endométrio/citologia , Ginatresia/terapia , Infertilidade Feminina/terapia , Menstruação/sangue , Células Estromais/transplante , Adulto , Endométrio/diagnóstico por imagem , Feminino , Humanos , Infertilidade Feminina/diagnóstico por imagem , Estudos Prospectivos , Transplante Autólogo , Resultado do Tratamento , Ultrassonografia
11.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 33(3): 365-9, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23713252

RESUMO

OBJECTIVE: To study the effects of Bushen Zhuyun Decoction (BZD) on the reproductive capacity of mice. METHODS: Totally 60 female Kunming mice were randomly divided into the experimental group and the control group. BZD was perfused by gastric tube to mice in the experimental group, twice daily. Meanwhile, mice in the control group were administered with normal saline by gastrogavage. Mice were sacrificed on the 10th day and the 20th day of medication respectively, 15 mice each time in each group. The serum levels of estradiol and progesterone were detected by radioimmunoassay. The morphological changes of uterus and ovary were observed using HE staining. The expressions of leukaemia inhibitory factor (LIF), epidermal growth factor (EGF), and calcitionin (CT) were determined using immunohistochemical assay. RESULTS: Compared with the control group at the same time point, the weights of uterus and ovary increased, the serum levels of estradiol and progestogen increased, the expressions of LIF, CT, and EGF increased in the experimental group on the 10th day and the 20th day of medication (P <0.05, P <0.01). Better results were shown on the 20th day of medication (P <0.05). Histological results showed increased ovarian follicle numbers, increased endometrial gland numbers, endometrial hyperplasia (stratiform arranged), and increased stromal cells in the experimental group, especially on the 20th day of medication. CONCLUSION: BZD could improve the reproductive capacity by advancing the development of generative organs, promoting the secretion of estradiol and progestogen and the follicular growth, and increasing the receptivity of endometrium.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Endométrio/metabolismo , Ovário/efeitos dos fármacos , Útero/efeitos dos fármacos , Animais , Estradiol/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos , Tamanho do Órgão , Progesterona/metabolismo
12.
Differentiation ; 86(4-5): 141-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24485751

RESUMO

Human embryonic germ cells (hEGCs) are a valuable and underutilized source of pluripotent stem cells. Unlike embryonic stem cells, which have been extensively studied, little is known about the factors that regulate hEGC derivation and maintenance. This study demonstrates for the first time a central role for selective activation of PDGFR signaling in the derivation and maintenance of pluripotency in hEGCs. In the study, hEGCs were found to express PDGF receptor α at high levels compared to human embryonic stem cells (hESCs). PDGF significantly improved formation of alkaline phosphatase (AP) positive hEGC colonies. We subsequently determined that PDGF activates the phosphatidylinositol-3-kinase (PI3K) pathway as phosphorylation of AKT was up-regulated in response to PDGF. Furthermore, inhibition of PI3K signaling using small molecular inhibitor LY294002 led to significantly decreased AP positive hEGC colony formation whereas inhibition of MAPK pathway using U0126 had a negligible effect. We established a primary mechanism for PDGF mediated derivation and maintenance of hEGCs by demonstrating that OCT4 was upregulated and PTEN was suppressed in a dose dependent manner in response to PDGF.


Assuntos
Células-Tronco Embrionárias/citologia , Células Germinativas/citologia , Fosfatidilinositol 3-Quinases/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Fosfatase Alcalina/metabolismo , Células Germinativas/metabolismo , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Células-Tronco Pluripotentes/citologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Transdução de Sinais
13.
Yi Chuan ; 30(3): 263-8, 2008 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-18331991

RESUMO

Mitochondria are essential organelles that generate cellular energy in cells. Mutations of mitochondrial DNA (mtDNA) have been identified in various types of cancer, suggesting a complex relationship between mtDNA and cancer. This review focuses on the possible correlation between the mtDNA mutation and cancer. Additionally, possible causes for mtDNA mutations and applications for detecting mtDNA mutations in cancer are discussed.


Assuntos
DNA Mitocondrial/genética , Neoplasias/genética , Humanos , Mutação
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