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1.
Cancer Sci ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38508217

RESUMO

N6-Methyladenosine (m6A) is a important process regulating gene expression post-transcriptionally. Programmed death ligand 1 (PD-L1) is a major immune inhibitive checkpoint that facilitates immune evasion and is expressed in tumor cells. In this research we discovered that Wilms' tumor 1-associated protein (WTAP) degradation caused by ubiquitin-mediated cleavage in cancer cells (colorectal cancer, CRC) under hypoxia was inhibited by Pumilio homolog 1 (PUM1) directly bound to WTAP. WTAP enhanced PD-L1 expression in a way that was m6A-dependent. m6A "reader," Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) identified methylated PD-L1 transcripts and subsequently fixed its mRNA. Additionally, we found that T-cell proliferation and its cancer cell-killing effects were prevented by overexpression of WTAP in vitro and in vivo. Overexpression prevented T cells from proliferating and killing CRC by maintaining the expression of PD-L1. Further evidence supporting the WTAP-PD-L1 regulatory axis was found in human CRC and organoid tissues. Tumors with high WTAP levels appeared more responsive to anti-PD1 immunotherapy, when analyzing samples from patients undergoing treatment. Overall, our findings demonstrated a novel PD-L1 regulatory mechanism by WTAP-induced mRNA epigenetic regulation and the possible application of targeting WTAP as immunotherapy for tumor hypoxia.

2.
Arch. endocrinol. metab. (Online) ; 68: e220491, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1533663

RESUMO

SUMMARY Primary pigmented nodular adrenocortical disease (PPNAD) is a rare adrenocorticotropin hormone (ACTH)-independent Cushing's syndrome (CS). Pediatric patients with PPNAD typically have unusual skin lesions and slow growth with unknown causes. We present a case of a female Chinese patient with PPNAD caused by the germline PRKACA gene copy number gain of chromosome 19. The patient initially presented with kidney stones, short stature, and obesity. After further testing, it was discovered that the patient had diabetes, mild hypertension, low bone mass, a low ACTH level, and hypercortisolemia, and neither the low-dose or high-dose dexamethasone suppression test was able to inhibit hematuric cortisol, which paradoxically increased. PPNAD was pathologically diagnosed after unilateral adrenalectomy. Chromosome microarrays and whole exon sequencing analyses of the peripheral blood, as well as testing of sectioned adrenal tissue, showed a rise in the copy number of the duplication-containing PRKACA gene on chromosome 19p13.13p13.12, a de novo but not heritable gene defect that causes disease. The clinical signs and symptoms supported the diagnosis of Carney complex (CNC). One significant mechanism of CNC pathogenesis may be the rise in germline PRKACA copy number of chromosome 19. When assessing PPNAD patients for CNC, the possibility of PRKACA gene amplification should be considered. The effect of PRKACA gene amplification on the clinical manifestations of CNC needs to be confirmed by more cases.

3.
Arch Endocrinol Metab ; 68: e220491, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37988664

RESUMO

Primary pigmented nodular adrenocortical disease (PPNAD) is a rare adrenocorticotropin hormone (ACTH)-independent Cushing's syndrome (CS). Pediatric patients with PPNAD typically have unusual skin lesions and slow growth with unknown causes. We present a case of a female Chinese patient with PPNAD caused by the germline PRKACA gene copy number gain of chromosome 19. The patient initially presented with kidney stones, short stature, and obesity. After further testing, it was discovered that the patient had diabetes, mild hypertension, low bone mass, a low ACTH level, and hypercortisolemia, and neither the low-dose or high-dose dexamethasone suppression test was able to inhibit hematuric cortisol, which paradoxically increased. PPNAD was pathologically diagnosed after unilateral adrenalectomy. Chromosome microarrays and whole exon sequencing analyses of the peripheral blood, as well as testing of sectioned adrenal tissue, showed a rise in the copy number of the duplication-containing PRKACA gene on chromosome 19p13.13p13.12, a de novo but not heritable gene defect that causes disease. The clinical signs and symptoms supported the diagnosis of Carney complex (CNC). One significant mechanism of CNC pathogenesis may be the rise in germline PRKACA copy number of chromosome 19. When assessing PPNAD patients for CNC, the possibility of PRKACA gene amplification should be considered. The effect of PRKACA gene amplification on the clinical manifestations of CNC needs to be confirmed by more cases.


Assuntos
Doenças do Córtex Suprarrenal , Síndrome de Cushing , Humanos , Criança , Feminino , Doenças do Córtex Suprarrenal/genética , Doenças do Córtex Suprarrenal/diagnóstico , Doenças do Córtex Suprarrenal/patologia , Síndrome de Cushing/genética , Adrenalectomia/efeitos adversos , Hidrocortisona , Hormônio Adrenocorticotrópico , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico
4.
Front Psychiatry ; 14: 1230807, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37867768

RESUMO

Difficulties in emotion regulation (DER) and emotion reactivity (ER) are important causes and consequences of psychiatric disorders such as depression and anxiety, and previous research suggests that there are many interactions between them. Understanding the structure of their relationship, and which components may play a key role, will help provide insight into emotion disorders in adolescents and provide guidance for clinical interventions. In this study, we collected data from 483 adolescents and used network analysis methods to explore the relationship between DER and ER, specifically looking for core nodes. The results showed that "limited access to emotion regulation strategies" was the most central node in the network. Furthermore, by adding nodes for depression and anxiety to this network, we found that anxiety had the strongest relationship with ER, while depression had a stronger relationship with DER. Thus, our findings suggest that for anxiety disorders, the strong association with ER highlights a potentially promising area for intervention development, whereas for depression, the association with DER points to the possibility of clarifying emotions and exploring coping strategies, acknowledging the complex interplay between depressive and anxious symptoms.

5.
Neuro Endocrinol Lett ; 44(7): 427-431, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37874555

RESUMO

INTRODUCTION: Acute thyrotoxic myopathy (ATM) is a rare and potentially lethal complication of thyrotoxicosis. The typical clinical symptoms of ATM are characterized by bulbar paralysis. Reports of the successful treatment of ATM are sporadic due to its low incidence. However, no English literature has reported Chinese patients with ATM and neck pain. Here, we report for the first time a Chinese patient with ATM and neck pain who recovered through large doses of systemic glucocorticoids and one intrathyroidal steroid injection. CASE REPORT: A 23-year-old woman visited our hospital with a two-year history of progressive weakness of her bulbar muscles, hoarseness, cough when swallowing, dysphagia, and a one-month history of recurrent painful swelling of the thyroid gland. She was diagnosed with ATM, chronic thyrotoxic myopathy (CTM), and Graves' ophthalmopathy (GO) due to Graves' disease (GD). After she was treated with a combination of low-dose glucocorticoids, antithyroid drugs (ATDs), propranolol, and ultrasound-guided percutaneous intrathyroidal injection of glucocorticoids, her bulbar paralysis, proximal myopathy, and neck pain simultaneously improved without recurrence during follow-up. To our knowledge, this is the first case report of a patient with ATM, CTM, GD, GO and neck pain treated by administering a combination of low-dose glucocorticoids, one intrathyroidal steroid injection and antithyroid agents. CONCLUSIONS: Clinicians should consider ATM and intervene with aggressive glucocorticoid therapy, and this is the key to reversing the progression of ATM when a patient has bulbar paralysis and thyrotoxic symptoms. Our case report references the clinical diagnosis and treatment of such cases.


Assuntos
Paralisia Bulbar Progressiva , Doença de Graves , Oftalmopatia de Graves , Doenças Musculares , Tireotoxicose , Humanos , Feminino , Adulto Jovem , Adulto , Paralisia Bulbar Progressiva/complicações , Paralisia Bulbar Progressiva/tratamento farmacológico , Cervicalgia/etiologia , Cervicalgia/complicações , Tireotoxicose/complicações , Tireotoxicose/tratamento farmacológico , Tireotoxicose/diagnóstico , Doença de Graves/complicações , Doença de Graves/tratamento farmacológico , Antitireóideos/uso terapêutico , Glucocorticoides/uso terapêutico , Doenças Musculares/complicações , Doenças Musculares/tratamento farmacológico , Esteroides/uso terapêutico
6.
J Gastrointest Oncol ; 14(1): 233-244, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36915463

RESUMO

Background: Colorectal cancer (CRC) is the third most common cancer and the fourth most common cause of cancer-related death worldwide. Advanced stage CRC, during the recent past, had a dismal prognosis and only a few available treatments. Pumilio homologous protein 1 (PUM1) is reportedly aberrant in human malignancies, including CRC. However, the role of PUM1 in the regulation of tumor-initiating cells (T-ICs) remains unknown. Methods: The levels of messenger RNAs (mRNAs) were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunoblot analyses. Statistical analyses were performed to determine the associations between the levels of PUM1 and tumor features and patient outcomes. Whether PUM1 is a downstream target of miR-218-5p was verified by bioinformatics target gene prediction and qRT-PCR. Results: Herein, it was found that T-ICs, chemoresistance, and recurrent CRC samples all manifest increased PUM1 expression. Functional investigations have shown that PUM1 increased the self-renewal, tumorigenicity, malignant proliferation, and chemoresistance of colorectal cells. PUM1 activates the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) signaling pathway biochemically. Furthermore, it was discovered that miR-218-5p specifically targets T-ICs' PUM1 3'-untranslated region (3'-UTR). More importantly, the PUM1/PI3K/AKT axis regulates CRC cells' responses to treatment with cetuximab, and PUM1 overexpression increased cetuximab resistance. More evidence points to the possibility that low PUM1 may predict cetuximab benefits in CRC patients after analysis of the patient cohort, patient-derived tumor organoids, and patient-derived xenografts (PDXs). Conclusions: Taken together, the result of this work points to the critical function of the miR-218-5p/PUM1/PI3K/AKT regulatory circuit in regulating T-ICs characteristics and thus suggests possible therapeutic targets for CRC.

7.
Eur J Nutr ; 62(2): 771-782, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36261730

RESUMO

PURPOSE: Fruit intake is beneficial to several chronic diseases, but controversial in diabetes. We aimed to investigate prospectively the associations of whole fresh fruit intake with risk of incident type 2 diabetes (T2D) in subjects with different glucose regulation capacities. METHODS: The present study included 79,922 non-diabetic participants aged ≥ 40 years from an ongoing nationwide prospective cohort in China. Baseline fruit intake information was collected by a validated food frequency questionnaire. Plasma HbA1c, fasting and 2 h post-loading glucose levels were measured at both baseline and follow-up examinations. Cox proportional hazards models were used to calculate hazard ratio (HR) and 95% confidence intervals (CI) for incident diabetes among participants with normal glucose tolerance (NGT) and prediabetes, after adjusted for multiple confounders. Restricted cubic spline analysis was applied for dose-response relation. RESULTS: During a median 3.8-year follow-up, 5886 (7.36%) participants developed diabetes. Overall, we identified a linear and dose-dependent inverse association between dietary whole fresh fruit intake and risk of incident T2D. Each 100 g/d higher fruit intake was associated with 2.8% lower risk of diabetes (HR 0.972, 95%CI [0.949-0.996], P = 0.0217), majorly benefiting NGT subjects with 15.2% lower risk (HR 0.848, 95%CI [0.766-0.940], P = 0.0017), while not significant in prediabetes (HR 0.981, 95%CI 0.957-4.005, P = 0.1268). Similarly, the inverse association was present in normoglycemia individuals with a 48.6% lower risk of diabetes when consuming fruits > 7 times/week comparing to those < 1 time/week (HR 0.514, 95% CI [0.368-0.948]), but not in prediabetes (HR 0.883, 95% CI [0.762-1.023]). CONCLUSION: These findings suggest that higher frequency and amount of fresh fruit intake may protect against incident T2D, especially in NGT, but not in prediabetes, highlighting the dietary recommendation of higher fresh fruit consumption to prevent T2D in normoglycemia population.


Assuntos
Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Humanos , Diabetes Mellitus Tipo 2/epidemiologia , Frutas , Estudos Prospectivos , Incidência , Glucose , Fatores de Risco
8.
Sci Total Environ ; 822: 153524, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35101506

RESUMO

Cyanobacterial blooms have been a global environmental problem for decades. Bioconversion by black soldier fly larvae (BSFL) has been widely reported to be a clean and efficient method to remove organic pollutants. In this study, BSFL bioconversion was used to treat cyanobacterial blooms. Antioxidants (a mixture of l-ascorbic acid [180 mg/kg fresh feed] and α-tocopherol [360 mg/kg fresh feed]) were added to compare bioconversion performance against a non-supplemented group. With increasing proportions of cyanobacteria (0%-25% dry mass), the bioconversion efficiency of the antioxidant group improved significantly compared to the control group, and the survival rate of larvae rose from 96.50-45.50% to 98.00-55.83% with antioxidant addition. The toxic effects of exogenous anti-nutrients could be reduced by the antioxidants through inactivation of trypsin inhibitor and enhancement of the microcystin-LR degradation rate. Overall, the BSFL bioremediation capacity was improved with addition of exogenous antioxidants, verifying both the effects and mechanism of antioxidant addition in promoting the bioconversion of cyanobacteria by BSFL and providing a basis for future application and study.


Assuntos
Cianobactérias , Dípteros , Animais , Antioxidantes , Larva , Nutrientes
9.
J Trace Elem Med Biol ; 70: 126918, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34954562

RESUMO

OBJECTIVE: To survey the status of iodine nutrition and the prevalence of thyroid diseases in Guangxi, China, and to explore the risk factors for positive thyroid antibody. METHODS: We used the multistage stratified cluster random sampling method to select a total of 2488 subjects from an urban and a rural location. All the subjects completed a questionnaire survey, blood and urine samples were also collected, and B-mode thyroid ultrasound was used to determine thyroid function and detect thyroid antibodies. RESULTS: 1) The median level of urinary iodine was 148.53 µg/L in school-age children in Guangxi, China. 2) The prevalence rates for thyroid diseases were as follows: hyperthyroidism, 0.89 %; subclinical hyperthyroidism, 1.05 %; hypothyroidism, 0.69 %; and subclinical hypothyroidism, 8.87 %. The rates of thyroid antibody positivity were as follows: thyroid peroxidase antibody (TPOAb), 13.60 %; thyroglobulin antibody (TGAb), 13.60 %; thyroid antibodies, 18.2 %; and thyroid nodules, 16.94 %. 3) The rate of TPOAb positivity was significantly higher in women aged 18-29, 30-39, 40-49, or 60-69 years than in men in the same age groups (P < 0.05), and the TGAb positivity rate was significantly higher in women than in men of the same age group (P < 0.05). 4) The rate of thyroid antibody positivity was significantly higher in individuals with iodine deficiency than in individuals with adequate iodine (21.6 % vs 18.4 %) or excess iodine (21.6 % vs 15.5 %) (both P < 0.05). 5) The female sex and a family history of thyroid diseases were the major risk factors for thyroid antibody positivity (odds ratio [OR] 3.010, P <0.05; OR 2.486, P <0.05). CONCLUSION: The overall level of iodine is adequate in Guangxi, China; this level should be maintained to prevent the thyroid diseases related with iodine deficiency or excess of iodine. Female sex and a family history of thyroid diseases are independent risk factors for thyroid antibody positivity.


Assuntos
Hipotireoidismo , Iodo , Doenças da Glândula Tireoide , Adolescente , Adulto , Idoso , Criança , China/epidemiologia , Feminino , Humanos , Hipotireoidismo/induzido quimicamente , Hipotireoidismo/epidemiologia , Iodeto Peroxidase , Iodo/urina , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Doenças da Glândula Tireoide/epidemiologia , Tireotropina , Adulto Jovem
10.
J Environ Manage ; 282: 111951, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33461088

RESUMO

Algal organic matter (AOM) and natural organic matter (NOM) from a typical eutrophic lake were comprehensively investigated in terms of their physico-chemical property, components and disinfection byproduct formation potentials (DBPFPs). The relationships between specific chemical properties of AOM and NOM with their corresponding DBPFPs were further evaluated during chlorination. Results indicated that AOM had lower specific UV absorbance (SUVA) but richer organic nitrogen contents than NOM. Fluorescence excitation emission matrix spectroscopy further demonstrated that AOM were chiefly composed of aromatic protein-like and soluble microbial byproduct-like matters, while NOM were mainly contributed from humic acid-like and soluble microbial byproduct-like substances. Although the molecular weight (MW) distribution of AOM and NOM showed no significant difference, size-exclusion chromatography with organic carbon as well as organic nitrogen detection (LC-OCD-OND) revealed that AOM were concentrated with the fraction of building blocks and NOM had higher concentrations of biopolymers and humics (HS). Moreover, AOM displayed higher DBPFPs than NOM, especially for nitrogenous DBPFP (N-DBPFP). MW < 1 kDa fractions both in AOM and NOM contributed the largest proportion to the formation of carbonaceous disinfection byproducts (C-DBPs). In addition, Pearson correlation analysis showed that bulk parameter SUVA was significantly relevant to the formation potentials of trihalomethane both in AOM and NOM, but was ineffective for carbonaceous DBPFP (C-DBPFP) prediction. Dissolved organic nitrogen contents in biopolymer and HS characterized by LC-OCD-OND had strong correlations with N-DBPFPs from AOM and NOM, indicating that LC-OCD-OND quantitative analysis could improve the prediction accuracy of the DBP formation than bulk parameters during NOM and AOM chlorination.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Desinfecção , Halogenação , Nitrogênio/análise , Trialometanos/análise , Poluentes Químicos da Água/análise
11.
Chemosphere ; 201: 189-196, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29524819

RESUMO

Oxcarbazepine (OXC), as a potent antiepileptic drug, is widely used in recent years, but its residue is potentially harmful to the environment. Although ozonation is a high-efficient technology for chemical oxidation during water treatment, it cannot completely mineralize organic matters, but partially transforms them into some unidentified by-products. In order to provide more insight into OXC ozonation process, the influencing factor, transformation mechanism and potential toxicity were comprehensively investigated in this study. The results showed that the optimal ozonation temperature was 20 °C with a pseudo-first-order reaction rate constant of 0.161 min-1. The increase of pH significantly enhanced OXC degradation, while the presence of bicarbonate caused a remarkable negative effect, manifesting that hydroxyl radical (OH) oxidation should play an important role in OXC ozonation. Moreover, transformation mechanism was further elucidated based on the identification of ten OXC-related by-products using UPLC-Q-TOF-MSn, which mainly consisted of electrophilic substitution, N-heterocyclic ring cleavage and re-arrangement, hydroxylation, carbonylation, demethoxylation and deamidation, etc. The toxicity evaluation, using US Environmental Protection Agency Toxicity Estimation Software Tool (US-EPA TEST), suggested that most identified by-products were probably more toxic than OXC itself. Besides, further experiments, by measuring inhibitory effect of ozonated mixture on Vibrio fischeri bioluminescence, demonstrated that by-products with higher toxicity tended to be accumulated under a short reaction time. Taken together, the present investigation provided valuable information for further understanding OXC ozonation process, and suggested that special attention should be paid to the control and elimination of toxic transformation by-products in future studies.


Assuntos
Aliivibrio fischeri/crescimento & desenvolvimento , Carbamazepina/análogos & derivados , Ozônio/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Purificação da Água/métodos , Aliivibrio fischeri/efeitos dos fármacos , Anticonvulsivantes/química , Anticonvulsivantes/toxicidade , Carbamazepina/química , Carbamazepina/toxicidade , Oxcarbazepina , Oxirredução
12.
Huan Jing Ke Xue ; 38(7): 2883-2892, 2017 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964629

RESUMO

Disinfection byproduct(DBP) precursors during the wastewater regeneration processes were separated into hydrophilic fraction(HPI), hydrophobic fraction(HPO) and transphilic fraction(TPI) with macroporous resin. DBP precursors in these water samples were characterized with fluorescence excitation emission matrix, Fourier transformation infrared and nuclear magnetic resonance, and were further tested for their DBP formation potential(DBPFP) after chlorination. The results indicated that main DBP precursors in sewage were humic acid and aliphatic hydrocarbons, and were mainly dominated by HPI. Primary treatment(sedimentation) could effectively remove hydrophobic humic acid through the mutual exclusion between HPO and water. The removal of humic acid would lead to the obvious reduction of carbonaceous disinfection byproduct formation potential(C-DBPFP). In addition, nitrogenous disinfection byproduct formation potential(N-DBPFP) was found to be increased due to the increase of DON/DOC value. Although secondary treatment(biotreatment) was effective in removing humic acid and aliphatic hydrocarbons, it could produce a large amount of soluble microbial products(SMP), which led to the enhancement of HPO percentage. And the accumulation of SMP resulted in the significant increase of C-DBPFP and N-DBPFP. Humic acid and hydrophobic SMP could be removed by the advanced treatment(cloth filtration), leading to the reduction of HPO percentage and the increase of HPI percentage. The decrease of humic acid and hydrophobic SMP would cause the reduction of C-DBPFP and N-DBPFP in the advanced treatment.

13.
Huan Jing Ke Xue ; 38(10): 4340-4347, 2017 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965220

RESUMO

The model of high solid anaerobic digestion was used by improving the degree of homogeneity of the reaction system and biogas slurry reflux to gradually increase the material load. The vinegar residue-efficient anaerobic digestion system was successfully constructed without pretreatment.The optimum anaerobic digestibility was observed when the material loading of the reaction system reached 6.15 g·(L·d)-1, when the amount of biogas produced per unit of dry material was 396 mL·g-1, and the amount of methane produced per unit of dry material was 211 mL·g-1. The degradation rate of hemicellulose reached 63.66%, which was the main reason for the improvement of anaerobic digestion performance. The degradation rates of cellulose and lignin were 21.46% and 24.43%, respectively. The lower degradation efficiency was mainly due to the complicated degradation of the benzene ring structure in lignin and hindered hydrolysis of cellulose, which had a shielding effect on cellulose degradation.


Assuntos
Ácido Acético , Reatores Biológicos , Celulose/metabolismo , Lignina/metabolismo , Eliminação de Resíduos Líquidos , Anaerobiose , Biocombustíveis , Metano
14.
Mol Microbiol ; 101(2): 250-64, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27061942

RESUMO

Polarisome is a protein complex that plays an important role in polarized growth in fungi by assembling actin cables towards the site of cell growth. For proper morphogenesis, the polarisome must localize to the right place at the right time. However, the mechanisms that control polarisome localization remain poorly understood. In this study, using the polymorphic fungus Candida albicans as a model, we have discovered that the cyclin-dependent kinase (CDK) Cdc28 phosphorylates the polarisome scaffold protein Spa2 to govern polarisome localization during both yeast and hyphal growth. In a yeast cell cycle, Cdc28-Clb2 phosphorylates Spa2 and controls the timing of polarisome translocation from the bud tip to the bud neck. And during hyphal development, Cdc28-Clb2 and the hyphal-specific Cdc28-Hgc1 cooperate to enhance Spa2 phosphorylation to maintain the polarisome at the hyphal tip. Blocking the CDK phosphorylation causes premature tip-to-neck translocation of Spa2 during yeast growth and inappropriate septal localization of Spa2 in hyphae and abnormal hyphal morphology under certain inducing conditions. Together, our results generate new insights into the mechanisms by which fungi regulate polarisome localization in the control of polarized growth.


Assuntos
Proteína Quinase CDC28 de Saccharomyces cerevisiae/metabolismo , Polaridade Celular/fisiologia , Proteínas do Citoesqueleto/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Ciclo Celular/genética , Polaridade Celular/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica/genética , Hifas/crescimento & desenvolvimento , Hifas/metabolismo , Fosforilação , Saccharomyces cerevisiae/metabolismo
15.
Development ; 143(1): 35-44, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26586222

RESUMO

The mechanism for the basal targeting of the Miranda (Mira) complex during the asymmetric division of Drosophila neuroblasts (NBs) is yet to be fully understood. We have identified conserved Phosphotyrosyl phosphatase activator (PTPA) as a novel mediator for the basal localization of the Mira complex in larval brain NBs. In mutant Ptpa NBs, Mira remains cytoplasmic during early mitosis and its basal localization is delayed until anaphase. Detailed analyses indicate that PTPA acts independent of and before aPKC to localize Mira. Mechanistically, our data show that the phosphorylation status of the T591 residue determines the subcellular localization of Mira and that PTPA facilitates the dephosphorylation of T591. Furthermore, PTPA associates with the Protein phosphatase 4 complex to mediate localization of Mira. On the basis of these results, a two-step process for the basal localization of Mira during NB division is revealed: cortical association of Mira mediated by the PTPA-PP4 complex is followed by apical aPKC-mediated basal restriction.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/embriologia , Células-Tronco Neurais/metabolismo , Neurogênese/fisiologia , Proteína Quinase C/metabolismo , Animais , Divisão Celular Assimétrica/fisiologia , Linhagem Celular , Fosfoproteínas Fosfatases/metabolismo , Fosforilação
16.
Ann Endocrinol (Paris) ; 76(5): 620-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26514948

RESUMO

OBJECTIVES: Aberrant circulating adipokines are considered to be related to the pathological mechanism of polycystic ovary syndrome (PCOS). This study aims to evaluate the relationship between plasma omentin-1 levels, metabolic and hormonal parameters in the setting of non-obese Chinese women with PCOS. MATERIAL AND METHODS: This was a case-controlled, cross-sectional study of 153 non-obese (BMI<25kg/m(2)) PCOS and 114 age-matched healthy non-obese control individuals. Levels of plasma omentin-1, fasting blood glucose, insulin and sexual hormones and ovary volume were analyzed in all subjects. RESULTS: Plasma omentin-1 levels of non-obese PCOS individuals were significantly lower than in healthy non-obese controls. Body Mass Index (BMI), homeostasis model of assessment for insulin resistance index (HOMA-IR), levels of testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), LH/FSH ratio and ovary volume (OV) were significantly higher in subjects with PCOS than controls. In the HOMA-IR stratified subgroups, PCOS individuals with insulin resistance had lower omentin-1 than those without insulin resistance after BMI adjustment. Omentin-1 was negatively correlated with BMI, HOMA-IR and fasting insulin. Multiple linear regressions revealed that BMI contributed to omentin-1 levels. Ovary volume was negatively correlated to HOMA-IR but had no correlation with omentin-1. CONCLUSIONS: Plasma omentin-1 concentrations were decreased in the non-obese PCOS group. Insulin resistance could further decrease plasma omentin-1 in non-obese individuals with PCOS independent of BMI status.


Assuntos
Citocinas/sangue , Resistência à Insulina/fisiologia , Lectinas/sangue , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/fisiopatologia , Adolescente , Adulto , Glicemia/análise , Índice de Massa Corporal , Peso Corporal , Estudos de Casos e Controles , China , Estudos Transversais , Jejum , Feminino , Hormônio Foliculoestimulante/sangue , Proteínas Ligadas por GPI/sangue , Humanos , Insulina/sangue , Hormônio Luteinizante/sangue , Obesidade , Ovário/patologia , Síndrome do Ovário Policístico/patologia , Testosterona/sangue , Adulto Jovem
17.
Chemosphere ; 119: 326-333, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25038548

RESUMO

Oxidation kinetics and degradation pathways of phenazone (an analgesic and antipyretic drug) upon reaction with O3 were investigated. Kinetic studies on degradation of phenazone were carried out under different operating conditions such as temperature, pH, anions and H2O2 addition. Results showed that the degradation followed the pseudo-first-order kinetic model. The reaction rate constant (kobs) of phenazone reached the maximum at 20 °C (9.653×10(-3) s(-1)). The presence of NO3(-) could enhance the degradation rate, while the addition of HCO3(-), SO4(2)(-), Cl(-) and the rise of pH showed negative effects on the ozonation of phenazone. H2O2 addition increased the phenazone degradation efficiency by 45.9% with the optimal concentration of 0.135 mM. Reaction by-products were evaluated by UPLC-Q-TOF-MS, which allowed the identification of a total of 10 by-products. The transformation pathways of phenazone ozonation consisted mainly of electrophilic addition and substitution, pyrazole ring opening, hydroxylation, dephenylization and coupling. The toxicity of these intermediate products showed that they are expected not to be more toxic than phenazone, with the exception of P7 (aniline) and P10 (1,5-dimethyl-4-((1-methyl-2-phenylhydrazinyl)methoxy)-2-phenyl-1H-pyrazol-3(2H)-one).


Assuntos
Anti-Inflamatórios não Esteroides/química , Antipirina/química , Oxidantes/química , Ozônio/química , Poluentes Químicos da Água/química , Água Potável , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Cinética , Nitratos/química , Oxirredução , Soluções , Temperatura , Purificação da Água
18.
J Clin Lipidol ; 8(6): 618-629, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25499945

RESUMO

BACKGROUND: The relation between the ABCB1 and CYP7A1 genes and serum lipid levels and lipid-lowering efficacy of statin treatment is inconsistent. OBJECTIVE: The purpose of this meta-analysis was to explore the associations between the ABCB1 and CYP7A1 genes and serum lipid levels and lipid-lowering efficacy of statin treatment. METHODS: MEDLINE, EMBASE, and the Cochrane Library databases were searched systematically for studies of associations between relevant single nucleotide polymorphisms C3435 T (ABCB1), G2677 A/T (ABCB1), and A-204C (CYP7A1) and serum lipid levels or statin treatment. Associations were assessed in pooled data by calculating mean difference with 95% confidence intervals. RESULTS: Seventeen studies with 4890 patients were included in this meta-analysis. The "AA" group at A-204C (CYP7A1) had lower serum total cholesterol (TC) levels than "AC + CC" group. The "AA" group at A-204C (CYP7A1) had greater reduction in low-density lipoprotein cholesterol (LDL-C) with statin treatment than "AC + CC" group. The "GG" group at G2677 A/T (ABCB1) had less reduction in TC and LDL-C with statin treatment than "non-GG" group. CONCLUSIONS: The A-204C (CYP7A1) polymorphism was associated with the level of TC and the lipid-lowering efficacy of statin treatment in the level of LDL-C. The G2677 A/T (ABCB1) polymorphism was associated with the lipid-lowering efficacy of statin treatment in the levels of LDL-C and TC.


Assuntos
Colesterol 7-alfa-Hidroxilase/genética , LDL-Colesterol/sangue , Dislipidemias/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipolipemiantes/uso terapêutico , Triglicerídeos/sangue , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , LDL-Colesterol/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único , Resultado do Tratamento , Triglicerídeos/genética
19.
Eukaryot Cell ; 13(12): 1548-56, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25326521

RESUMO

The cyclic AMP (cAMP)-protein kinase A (PKA) signaling activates virulence expression during hyphal development in the fungal human pathogen Candida albicans. The hyphal growth is characterized by Golgi polarization toward the hyphal tips, which is thought to enhance directional vesicle transport. However, how the hypha-induction signal regulates Golgi polarization is unknown. Gyp1, a Golgi-associated protein and the first GTPase-activating protein (GAP) in the Rab GAP cascade, critically regulates membrane trafficking from the endoplasmic reticulum to the plasma membrane. Here, we report a novel pathway by which the cAMP-PKA signaling triggers Golgi polarization during hyphal growth. We demonstrate that Gyp1 plays a crucial role in actin-dependent Golgi polarization. Hyphal induction activates PKA, which in turn phosphorylates Gyp1. Phosphomimetic mutation of four PKA sites identified by mass spectrometry (Gyp1(4E)) caused strong Gyp1 polarization to hyphal tips, whereas nonphosphorylatable mutations (Gyp1(4A)) abolished it. Gyp1(4E) exhibited enhanced association with the actin motor Myo2, while Gyp1(4A) showed the opposite effect, providing a possible mechanism for Golgi polarization. A GAP-dead Gyp1 (Gyp1(R292K)) showed strong polarization similar to that seen with Gyp1(4E), indicating a role for the GAP activity. Mutating the PKA sites on Gyp1 also impaired the recruitment of a late Golgi marker, Sec7. Furthermore, proper PKA phosphorylation and GAP activity of Gyp1 are required for virulence in mice. We propose that the cAMP-PKA signaling directly targets Gyp1 to promote Golgi polarization in the yeast-to-hypha transition, an event crucial for C. albicans infection.


Assuntos
Candida albicans/enzimologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Complexo de Golgi/enzimologia , Animais , Candida albicans/patogenicidade , Candidíase/enzimologia , Candidíase/microbiologia , Hifas/enzimologia , Hifas/patogenicidade , Rim/microbiologia , Rim/patologia , Camundongos , Fosforilação , Processamento de Proteína Pós-Traducional , Transporte Proteico , Transdução de Sinais , Virulência
20.
mBio ; 5(1): e00915-13, 2014 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-24496790

RESUMO

UNLABELLED: Nap1 has long been identified as a potential septin regulator in yeasts. However, its function and regulation remain poorly defined. Here, we report functional characterization of Nap1 in the human-pathogenic fungus Candida albicans. We find that deletion of NAP1 causes constitutive filamentous growth and changes of septin dynamics. We present evidence that Nap1's cellular localization and function are regulated by phosphorylation. Phos-tag gel electrophoresis revealed that Nap1 phosphorylation is cell cycle dependent, exhibiting the lowest level around the time of bud emergence. Mass spectrometry identified 10 phosphoserine and phosphothreonine residues in a cluster near the N terminus, and mutation of these residues affected Nap1's localization to the septin ring and cellular function. Nap1 phosphorylation involves two septin ring-associated kinases, Cla4 and Gin4, and its dephosphorylation occurs at the septin ring in a manner dependent on the phosphatases PP2A and Cdc14. Furthermore, the nap1Δ/Δ mutant and alleles carrying mutations of the phosphorylation sites exhibited greatly reduced virulence in a mouse model of systemic candidiasis. Together, our findings not only provide new mechanistic insights into Nap1's function and regulation but also suggest the potential to target Nap1 in future therapeutic design. IMPORTANCE: Septins are conserved filament-forming GTPases involved in a wide range of cellular events, such as cytokinesis, exocytosis, and morphogenesis. In Candida albicans, the most prevalent human fungal pathogen, septin functions are indispensable for its virulence. However, the molecular mechanisms by which septin structures are regulated are poorly understood. In this study, we deleted NAP1, a gene encoding a putative septin regulator, in C. albicans and found that cells lacking NAP1 showed abnormalities in morphology, invasive growth, and septin ring dynamics. We identified a conserved N-terminal phosphorylation cluster on Nap1 and demonstrated that phosphorylation at these sites regulates Nap1 localization and function. Importantly, deletion of NAP1 or mutation in the N-terminal phosphorylation cluster strongly reduced the virulence of C. albicans in a mouse model of systemic infection. Thus, this study not only provides mechanistic insights into septin regulation but also suggests Nap1 as a potential antifungal target.


Assuntos
Candida albicans/genética , Candida albicans/metabolismo , Regulação Fúngica da Expressão Gênica , Substâncias Macromoleculares/metabolismo , Proteína 1 de Modelagem do Nucleossomo/metabolismo , Septinas/metabolismo , Animais , Candida albicans/citologia , Candida albicans/crescimento & desenvolvimento , Candidíase/microbiologia , Candidíase/patologia , Ciclo Celular , Modelos Animais de Doenças , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Deleção de Genes , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos BALB C , Mutagênese Sítio-Dirigida , Proteína 1 de Modelagem do Nucleossomo/química , Proteína 1 de Modelagem do Nucleossomo/genética , Fosforilação , Processamento de Proteína Pós-Traducional , Virulência
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