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1.
Environ Monit Assess ; 195(12): 1556, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38036894

RESUMO

Leather tanneries are known for chemical laden work environments and pulmonic complaints among workers. This study presents an analysis of tannery micro-environments emphasizing on size-based variation in composition of particulate matter and consequent respiratory dysfunctions. Qualitative (FTIR, SEM-EDX) and quantitative assessment (elemental composition, carbon forms) of PM10 and 2.5 has been employed. For lung function evaluation of workforce, spirometry with ATS proprieties was used. The peak concentrations of both PM10 and 2.5 have been found at PU, FU, and B&S. The LTCR for only Cr is high for both PM2.5 and PM10. HQ was high for Al, Cr, and Mn for both PM sizes. The maximum organic and secondary organic carbon in PM10 was found at FU and in PM2.5 at PU. The varied PM composition included carbohydrate (B&S, WMO), ether (S&S, P&S) and hydroxyl (B&S, S&S, P&S), proteins, polyenes, vinyl groups (S&S, P&S, FU), alcohols (PU and FU), and aldehyde present at PU. These results were armored by high organic and total carbon concentrations for the same sites. Therefore, PM are classified into biogenic (carbonaceous: microbial and animal remains) from PU and WMO, incidental (industrial, mixt physico-chemical character) from PU, FU, WMO, B&S and P&S, and geogenic (crustal mineral dust) from RHT, B&S, PU, and P&S. Furthermore, increase in metal concentrations in PM10 (Cr, Mn, Co, Ni, V, As, Be, Ba, and Cd) and PM2.5 (As, Pb) while TC, OC, and SOC in PM2.5 caused depreciation overall lung function. The exposure to biogenic and incidental PM nature are key cause of pulmonic dysfunction.


Assuntos
Poluentes Atmosféricos , Material Particulado , Humanos , Material Particulado/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Poeira/análise , Carbono/análise , Tamanho da Partícula
3.
Nat Chem Biol ; 15(7): 681-689, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31133756

RESUMO

The mechanisms by which cells adapt to proteotoxic stress are largely unknown, but are key to understanding how tumor cells, particularly in vivo, are largely resistant to proteasome inhibitors. Analysis of cancer cell lines, mouse xenografts and patient-derived tumor samples all showed an association between mitochondrial metabolism and proteasome inhibitor sensitivity. When cells were forced to use oxidative phosphorylation rather than glycolysis, they became proteasome-inhibitor resistant. This mitochondrial state, however, creates a unique vulnerability: sensitivity to the small molecule compound elesclomol. Genome-wide CRISPR-Cas9 screening showed that a single gene, encoding the mitochondrial reductase FDX1, could rescue elesclomol-induced cell death. Enzymatic function and nuclear-magnetic-resonance-based analyses further showed that FDX1 is the direct target of elesclomol, which promotes a unique form of copper-dependent cell death. These studies explain a fundamental mechanism by which cells adapt to proteotoxic stress and suggest strategies to mitigate proteasome inhibitor resistance.


Assuntos
Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Inibidores de Proteassoma/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Inibidores de Proteassoma/química , Bibliotecas de Moléculas Pequenas/química
4.
Int J Clin Pract ; 75(9): e14377, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34003539

RESUMO

AIMS: Insulin degludec/aspart (IDegAsp) and insulin glargine U300 (IGlarU300) have recently emerged as popular new-generation insulin analogues. The aim of this real-life study was to investigate the patient profiles in which IGlarU300 and IDegAsp were preferred and the insulin combinations after which each of them were mostly used and also to analyse the effect of these two insulin analogues on blood glucose regulation and hypoglycaemia. MATERIALS AND METHODS: The retrospective study included 174 patients that were switched from basal insulin, basal-bolus insulin, or premixed insulin to IGlarU300 or IDegAsp due to uncontrolled blood glucose levels or history of hypoglycaemia. Hypoglycaemia, body weight, body mass index (BMI), fasting plasma glucose (FPG) and HbA1c levels over 3-month periods were evaluated for each patient. RESULTS: There were 84 and 90 patients in the IGlarU300 and IDegAsp groups, respectively. Body weight was similar in both groups. Baseline FPG and HbA1c levels in the IGlarU300 and IDegAsp groups were 9.0%, 175.5 mg/dL and 9.4%, 193.5 mg/dL, respectively. A significant decrease was found in FPG and HbA1c levels in both groups (138.5, 7.8 vs 141.5, 8.2; P < .001 for all). Moreover, a significant weight gain was observed in both groups (P < .05 for both). The prevalence of hypoglycaemia in both groups decreased significantly and consistently between months 1 and 9 (P < .001). At month 12, although this decrease continued in the IGlarU300 group (P = .013), no significant decrease was observed in the IDegAsp group (P = .057). CONCLUSION: Both twice-daily IDegAsp ± bolus insulin and IGlarU300 basal bolus insulin therapies are effective and safe treatment modalities.


Assuntos
Diabetes Mellitus Tipo 2 , Insulina Aspart , Glicemia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemiantes , Insulina Glargina , Insulina de Ação Prolongada , Estudos Retrospectivos
5.
Indoor Air ; 30(3): 492-499, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31887240

RESUMO

Concentrations and emission rates of sixteen trace elements in emitted PM during heating soybean oil using three types of pans, including Teflon, granitium, and cast-iron, were investigated. Statistically significant decreases in Mn and Co emission rates were observed when the oil was heated in the cast-iron pan compared to Teflon and granitium pans. Among the released trace elements, Ni, Ba, Zn, and Cr had more contribution to the emission rate. The concentrations of Fe in the emitted PM1 were found to be higher when cast-iron pan (8.49 ± 3.35 µg/m3 ) was utilized compared to Teflon (8.05 ± 2.27 µg/m3 ) and granitium (7.45 ± 1.38 µg/m3 ). However, these increases were statistically insignificant. The results of our study support the hypothesis that the trace elements translocate from cooking pans into the heated oil and subsequently to the particulate phase. This translocation creates a new inhalation exposure route to trace elements in indoor environments.


Assuntos
Poluição do Ar em Ambientes Fechados , Monitoramento Ambiental , Exposição por Inalação , Material Particulado/análise , Oligoelementos
6.
Nat Commun ; 15(1): 3483, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664416

RESUMO

Chemical discovery efforts commonly target individual protein domains. Many proteins, including the EP300/CBP histone acetyltransferases (HATs), contain several targetable domains. EP300/CBP are critical gene-regulatory targets in cancer, with existing high potency inhibitors of either the catalytic HAT domain or protein-binding bromodomain (BRD). A domain-specific inhibitory approach to multidomain-containing proteins may identify exceptional-responding tumor types, thereby expanding a therapeutic index. Here, we discover that targeting EP300/CBP using the domain-specific inhibitors, A485 (HAT) or CCS1477 (BRD) have different effects in select tumor types. Group 3 medulloblastoma (G3MB) cells are especially sensitive to BRD, compared with HAT inhibition. Structurally, these effects are mediated by the difluorophenyl group in the catalytic core of CCS1477. Mechanistically, bromodomain inhibition causes rapid disruption of genetic dependency networks that are required for G3MB growth. These studies provide a domain-specific structural foundation for drug discovery efforts targeting EP300/CBP and identify a selective role for the EP300/CBP bromodomain in maintaining genetic dependency networks in G3MB.


Assuntos
Proteína p300 Associada a E1A , Redes Reguladoras de Genes , Meduloblastoma , Humanos , Meduloblastoma/genética , Meduloblastoma/tratamento farmacológico , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Proteína p300 Associada a E1A/metabolismo , Proteína p300 Associada a E1A/genética , Proteína p300 Associada a E1A/antagonistas & inibidores , Linhagem Celular Tumoral , Redes Reguladoras de Genes/efeitos dos fármacos , Animais , Domínios Proteicos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Camundongos , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , Antineoplásicos/farmacologia
7.
J Contemp Dent Pract ; 14(3): 371-4, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24171975

RESUMO

AIM: The aim of this study was to evaluate the minimum bactericidal concentrations (MBC) of root-end filling materials ProRoot MTA, MTA Angelus and IRM. MATERIALS AND METHODS: Macrodilution broth method was used. Microorganisms used were: Staphylococcus aureus (ATCC 29213), Enterococcus faecalis (ATCC 29212) and Streptococcus mutans. Serial two-fold dilutions of root-end filling samples were prepared in macrodilution tubes with concentrations ranging from 1/2 to 1/512. The samples dilutions were incubated for 24 hours. After incubation, 0.1 ml of diluted culture was inoculated onto the surface of supplemented sheep blood agar (Merck, Germany) and all plates were incubated at 37°C in aerobic condition for 24 hours. The MBC was defined as the lowest concentration of root-end filling samples where no growth was recorded. RESULTS: MBC of both mineral trioxide aggregate (MTA) products against S. aureus were recorded as 15.62 mg/ml and for IRM 31.25 mg/ml MBC for both MTA groups against E. faecalis were recorded as 31.25 mg/ml and for IRM 62.5 mg/ml. MBC of all root-end filling samples against S. mutans were recorded as 62.5 mg/ml. CONCLUSION: All tested root-end filling materials showed acceptable MBC against S. aureus and E. faecalis. CLINICAL SIGNIFICANCE: All tested materials can be used safely for filling of a root-end cavity.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Materiais Restauradores do Canal Radicular/farmacologia , Aerobiose , Compostos de Alumínio/farmacologia , Antibacterianos/administração & dosagem , Carga Bacteriana/efeitos dos fármacos , Técnicas Bacteriológicas , Bismuto/farmacologia , Compostos de Cálcio/farmacologia , Cimentos Dentários/farmacologia , Combinação de Medicamentos , Enterococcus faecalis/efeitos dos fármacos , Humanos , Teste de Materiais , Metilmetacrilatos/farmacologia , Testes de Sensibilidade Microbiana , Óxidos/farmacologia , Silicatos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Temperatura , Fatores de Tempo , Cimento de Óxido de Zinco e Eugenol/farmacologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-36919686

RESUMO

Chronic hepatitis B infection caused by Hepatitis B virus (HBV), influences over two billion people worldwide despite having an effective vaccine. With a total prevalence of 4.57%, there are 3.3 million estimated HBV carriers in Türkiye. Methylene-tetrahydrofolate reductase (MTHFR) arrange folate metabolism through nucleic acid synthesis and DNA methylation. C677T (rs1801133, p.Ala222Val) and A1298C (rs1801131, p.Glu429Ala) polymorphisms of MTHFR gene have effect of reducing the activity of enzyme. We purposed to investigate the correlation between C677T and A1298C polymorphisms of MTHFR gene with HBV infection in a Turkish population. One hundred eighteen HBV-infected participants and ninety healthy controls were incorporated in this research. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay was applied to discover the genotypes of MTHFR polymorphisms. We demonstrated that T allele and CT + TT genotype frequencies of C677T polymorphism were significantly increased in HBV-infected participants than healthy controls [p = 0.015, OR (95% Cl) = 1.7 (1.11-2.79) and p = 0.020, OR (95% Cl) = 1.9 (1.10-3.42), respectively). No significant associations were noted concerning the A1298C polymorphism (p > 0.05). CC-AA composite genotype was observed to be significantly elevated in healthy controls than HBV-infected participants (32.2% vs. 13.6%, p = 0.001). In addition, the frequency of T-C haplotype was found to be considerably higher in the patient group than control group (15.8% vs 11.8%, p = 0.018). In conclusion, we found that T allele of C677T polymorphism poses a risk factor for HBV infection. We also discovered a protective impact of the CC-AA composite genotype against HBV infection and a risk effect of the T-A haplotype for HBV-infection.


Assuntos
Vírus da Hepatite B , Hepatite B , Humanos , Predisposição Genética para Doença , Genótipo , Fatores de Risco , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Estudos de Casos e Controles , Tetra-Hidrofolatos/genética , Polimorfismo de Nucleotídeo Único , Frequência do Gene
9.
Curr Med Res Opin ; : 1-11, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37830875

RESUMO

OBJECTIVE: The use of herbal products/dietary supplements (HP/DS) in endocrinal chronic diseases is growing. However, no studies have evaluated their use in patients who present to endocrinology and metabolic diseases clinics. This descriptive study aims to investigate the rate of HP/DS use and the factors affecting this in patients who presented to Karadeniz Technical University (KTU) Farabi Hospital Endocrinology and Metabolic Diseases Clinic, Türkiye between 01.11.2021 and 01.05.2022. METHODS: Five hundred six questionnaires with acceptable data quality were included this investigation. The data were analyzed on SPSS version 23.0 software. The factors with the greatest effect on the use of HP/DS were determined using binary logistic regression analysis. RESULTS: Analysis showed that 49.4% of the participants used HP/DS. The main factors affecting the use of herbal products were age, diagnosis of the disease, and treatment compliance problems. The most frequently used products were lemon, cinnamon, black cumin, ginger, turmeric, and dill. The participants main sources of information about HP/DS were friends/relatives, the internet/social media, and television, respectively. 74.8% of the participants using HP/DS did not inform their physcisian/pharmacist about such use, although 81.8% of these nevertheless wished to receive information from these occupational groups. CONCLUSION: Herbal product monitoring in patients should be performed in collaboration with pharmacists, herbal product use should be investigated, and counseling services should be made available in order to maintain and promote public health.

10.
Dent Med Probl ; 60(3): 421-426, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37750735

RESUMO

BACKGROUND: The extrusion of apical debris is related to various factors, and may be affected by variations in technique or instrumentation system. Although the extrusion cannot be completely prevented, it is crucial to minimize the amount of extruded material. OBJECTIVES: The present study aimed to compare apical debris extrusion by the novel TruNatomy (TRN), OneCurve (OC) and ProTaper Next (PTN) instruments in curved root canals. MATERIAL AND METHODS: A total of 60 multi-rooted human mandibular molar teeth with moderate and severe curvature were selected and randomly divided into 3 groups. The root canals were prepared with the OC, TRN and PTN files. For collecting the debris extruded through the apical foramen, Eppendorf tubes were used. After the vaporizing period, the tubes were re-weighed, and the amount of the extruded debris was calculated by subtracting the initial weight from the final weight. Statistical analysis was performed with the Shapiro-Wilk and Kruskal-Wallis tests. The statistical significance level was set at p < 0.05. RESULTS: The least amount of debris was extruded with TRN and the greatest with PTN, but the difference between the groups was not significant (p = 0.257). CONCLUSIONS: All instrumentation systems were associated with debris extrusion. The tested file systems presented similar results in terms of apical debris extrusion in curved canals. The novel TRN system demonstrated promising results, comparable to OC and PTN.


Assuntos
Preparo de Canal Radicular , Ápice Dentário , Humanos , Ápice Dentário/cirurgia , Dente Molar/cirurgia
11.
Artigo em Inglês | MEDLINE | ID: mdl-36484570

RESUMO

Subacute thyroiditis (SAT) is an inflammatory thyroid disease with a frequency is 5% among all thyroid diseases. miRNAs are endogenous, non-coding RNAs ranging in length from 19 to 25 nucleotides. They play an important role in the posttranscriptional regulation of gene expression. In this study, we aimed to investigate whether the expression levels of two circulating miRNAs, MIR22 and MIR16-1, can be used as a parameter in the diagnosis and follow-up of SAT disease. Fifty patients diagnosed with SAT and 41 healthy controls were included in this study. Expression levels of miRNAs were determined by real time-PCR method. Expression data of miRNAs were calculated by fold change (2-ΔΔCt) method. The statistical significance of miRNA expression was evaluated by t-test. The expression levels of MIR22-3p and MIR16-1-3p were not found to be statistically different between SAT patients and controls and also between the patients in different stages (hyperthyroid, euthyroid, and hypothyroid) of the disease. According to correlation analyses, we observed a positive strong correlation between erythrocyte sedimentation rate (ESR) and the expression levels of MIR22-3p and MIR16-1-3p (r = 0.960, p = 0.000 and r = 0.865, p = 0.006, respectively), and a positive strong correlation between fT4 and the expression levels of MIR22-3p in SAT patients in euthyroid stage (r = 0.712, p = 0.047). In this study, we showed that the expression levels of MIR22-3p and MIR16-1-3p have correlation with clinical characteristics of SAT disease. Our results suggest that MIR22 and MIR16-1 may be effective in the pathogenesis of SAT.


Assuntos
MicroRNAs , Tireoidite Subaguda , Humanos , Tireoidite Subaguda/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Regulação da Expressão Gênica
12.
Aust Endod J ; 49 Suppl 1: 381-389, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36971332

RESUMO

To compare the penetration of Ah Plus and MTA Fillapex after irrigation activation with sonic, passive ultrasonic, SWEEPS and XP-Endo Finisher using confocal microscopy. Instrumented root canals of 160 mandibular premolar teeth were allocated randomly to four groups (n = 40/group) and eight subgroups according to the activation techniques and canal sealers (n = 20/subgroup). After the obturation, three sections at 1-2, 5-6 and 9-10 mm levels from the apex were examined. Penetration area and maximum penetration depth values were represented as mean and standard deviation, and results below 0.05 were considered statistically significant. For penetration area and maximum penetration depth, the statistical difference was found in terms of material, device and region (Maximum penetration depth: p = 0.006, p < 0.001, p < 0.001; Penetration area: p = 0.004, p < 0.001, p < 0.001). SWEEPS was found to be relatively higher than other groups. Sealers presented similar results when evaluated independently of the region. The use of SWEEPS for irrigation activation is promising in terms of tubule penetration.


Assuntos
Materiais Restauradores do Canal Radicular , Cavidade Pulpar , Projetos de Pesquisa , Dente Pré-Molar , Microscopia Confocal , Resinas Epóxi
13.
Rev Assoc Med Bras (1992) ; 69(7): e20230174, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37466599

RESUMO

OBJECTIVE: The objective of this study was to examine the effects of orlistat use on metabolic control and weight loss in diabetic and nondiabetic patients. METHODS: A total of 119 patients with body mass index≥40 kg/m2 and receiving orlistat therapy, who applied to the Endocrinology polyclinic between January 2016 and October 2019, were included. The patients' weight changes and biochemical values (i.e., fasting glucose, HbA1c, ALT, creatinine, and lipid parameters) were evaluated at the drug beginning and the last polyclinic control. The patients were divided into groups, whether they had diabetes or used metformin, and compared. RESULTS: The mean age of the 119 patients in the study was 45.3±11.5 years. A total of 94.1% of the patients were females and 5.9% were males. A total of 38.7% of the patients had diabetes and 29.4% had prediabetes. When the patients were compared to whether they had diabetes or used metformin, there was a statistically significant difference between the groups according to weight loss. The mean weight change of patients without diabetes and receiving metformin and orlistat was statistically significantly higher than that of patients with diabetes and receiving metformin and orlistat. DISCUSSION: It was determined that the weight loss effect of orlistat in obesity was seen in all groups, but this effect decreased in the diabetic group.


Assuntos
Fármacos Antiobesidade , Diabetes Mellitus Tipo 2 , Metformina , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Orlistate/uso terapêutico , Metformina/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Fármacos Antiobesidade/uso terapêutico , Lactonas/uso terapêutico , Redução de Peso
14.
Endocrine ; 82(1): 152-160, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37450216

RESUMO

PURPOSE: Acromegaly is closely related to increased oxidative stress and endothelial dysfunction (ED). This study aimed to evaluate, for the first time in the literature, signal peptide-CUB-EGF domain-containing protein 1 (SCUBE-1) and endothelial nitric oxide synthase e(NOS) levels in the setting of acromegaly. METHOD: A total of 56 acromegaly patients and a control group composed of 30 healthy volunteers were included in this study. In the postoperative follow-up, patients were grouped as active or in-remission according to their GH and IGF-1 levels in oral glucose stimulation test (OGST). After detailed physical examination of acromegaly patients and the control subjects, 8-hour fasting blood samples were collected to evaluate biochemical parameters including lipid profile, anterior pituitary hormones, and SCUBE-1 and e(NOS) levels. RESULTS: Inactive and active acromegaly was noted in 78.6% and 21.4% of patients, respectively. The median (min-max) SCUBE-1 levels were significantly higher in the inactive acromegaly and active acromegaly groups than in the control group (1.6(0.4-2.4) and 1.8(1.1-2.5) vs. 0.4(0.2-1.0) ng/mL, respectively, p < 0.001 for each). The median (min-max) e(NOS) levels were significantly higher in the inactive acromegaly and active acromegaly groups than in the control group (132.7 (26.8-602.9) and 137.3 (69.7-488.7) vs. 83.9 (16.4-218.7) pg/mL, p = 0.018 and p = 0.048, respectively). We have also detected positive correlations of e(NOS) with leukocyte (r = 0.307, p = 0.021) and neutrophil counts (r = 0.309, p = 0.021). CONCLUSION: Our study revealed for the first time in literature that SCUBE-1 levels, being a novel marker for ED, were significantly higher in acromegaly patients than in control subjects. When supported with clinical studies, SCUBE-1can be used as an early indicator of endothelial damage in acromegaly patients.


Assuntos
Acromegalia , Humanos , Fator de Crescimento Epidérmico , Glucose , Fator de Crescimento Insulin-Like I/metabolismo
15.
Aust Endod J ; 48(2): 258-265, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34259369

RESUMO

This study aimed to evaluate dentinal tubule penetration of the root canal filling material using various techniques such as cold lateral compaction, new generation thermoplastic core carrier and continuous-wave obturation. The root canals of premolar teeth were instrumented, and the teeth were allocated randomly to three groups (n = 15/group). After the obturation with three different techniques, three sections of 2-mm thickness at 2, 5 and 8-mm from the apex were examined under a confocal laser scanning microscope. The data were analysed of variance with a significance level of P < 0.05. There was no significant difference between techniques when parameters were evaluated in total (penetration depth P = 0.418, penetration area P = 0.701). The mean value of the cold lateral compaction group for maximum penetration depth was obtained higher than continuous wave (P = 0.004), whilst there was no significant difference between the thermoplastic core carrier and the other groups.


Assuntos
Guta-Percha , Materiais Restauradores do Canal Radicular , Cavidade Pulpar , Resinas Epóxi , Microscopia Confocal , Obturação do Canal Radicular/métodos , Preparo de Canal Radicular/métodos , Seringas
16.
Science ; 375(6586): 1254-1261, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35298263

RESUMO

Copper is an essential cofactor for all organisms, and yet it becomes toxic if concentrations exceed a threshold maintained by evolutionarily conserved homeostatic mechanisms. How excess copper induces cell death, however, is unknown. Here, we show in human cells that copper-dependent, regulated cell death is distinct from known death mechanisms and is dependent on mitochondrial respiration. We show that copper-dependent death occurs by means of direct binding of copper to lipoylated components of the tricarboxylic acid (TCA) cycle. This results in lipoylated protein aggregation and subsequent iron-sulfur cluster protein loss, which leads to proteotoxic stress and ultimately cell death. These findings may explain the need for ancient copper homeostatic mechanisms.


Assuntos
Ciclo do Ácido Cítrico , Cobre/metabolismo , Cobre/toxicidade , Morte Celular Regulada , Animais , Respiração Celular , Di-Hidrolipoil-Lisina-Resíduo Acetiltransferase/metabolismo , Degeneração Hepatolenticular/metabolismo , Homeostase , Humanos , Hidrazinas/toxicidade , Ionóforos/toxicidade , Proteínas Ferro-Enxofre/metabolismo , Lipoilação , Redes e Vias Metabólicas , Camundongos , Mitocôndrias/metabolismo
17.
J Med Chem ; 65(21): 14843-14863, 2022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-36270630

RESUMO

The ligand-activated nuclear receptor peroxisome-proliferator-activated receptor-γ (PPARG or PPARγ) represents a potential target for a new generation of cancer therapeutics, especially in muscle-invasive luminal bladder cancer where PPARγ is a critical lineage driver. Here we disclose the discovery of a series of chloro-nitro-arene covalent inverse-agonists of PPARγ that exploit a benzoxazole core to improve interactions with corepressors NCOR1 and NCOR2. In vitro treatment of sensitive cell lines with these compounds results in the robust regulation of PPARγ target genes and antiproliferative effects. Despite their imperfect physicochemical properties, the compounds showed modest pharmacodynamic target regulation in vivo. Improvements to the in vitro potency and efficacy of BAY-4931 and BAY-0069 compared to those of previously described PPARγ inverse-agonists show that these compounds are novel tools for probing the in vitro biology of PPARγ inverse-agonism.


Assuntos
PPAR gama , PPAR gama/metabolismo , Ligantes
18.
Science ; 377(6604): eabm5551, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35862544

RESUMO

To accelerate the translation of cancer nanomedicine, we used an integrated genomic approach to improve our understanding of the cellular processes that govern nanoparticle trafficking. We developed a massively parallel screen that leverages barcoded, pooled cancer cell lines annotated with multiomic data to investigate cell association patterns across a nanoparticle library spanning a range of formulations with clinical potential. We identified both materials properties and cell-intrinsic features that mediate nanoparticle-cell association. Using machine learning algorithms, we constructed genomic nanoparticle trafficking networks and identified nanoparticle-specific biomarkers. We validated one such biomarker: gene expression of SLC46A3, which inversely predicts lipid-based nanoparticle uptake in vitro and in vivo. Our work establishes the power of integrated screens for nanoparticle delivery and enables the identification and utilization of biomarkers to rationally design nanoformulations.


Assuntos
Antineoplásicos , Biomarcadores Farmacológicos , Proteínas de Transporte de Cobre , Composição de Medicamentos , Sistemas de Liberação de Fármacos por Nanopartículas , Nanopartículas , Neoplasias , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Proteínas de Transporte de Cobre/genética , Expressão Gênica , Genômica , Humanos , Lipossomos , Camundongos , Nanomedicina , Nanopartículas/administração & dosagem , Nanopartículas/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo
19.
Lasers Med Sci ; 26(4): 427-31, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20473775

RESUMO

The aim of this study is to compare the sealing efficacy of the retrograde cavity preparations prepared and filled with different equipment and materials. In the study, low speed burs, ultrasonic or Er, Cr:YSGG laser devices were used for cavity preparations and ProRoot MTA and MTA-Angelus as filling materials. Seventy-eight single-rooted teeth were instrumented, root filled, and grouped. Root-end cavities were prepared and filled by using the following: Group 1: Low-speed carbide bur + ProRoot MTA; Group 2: Low-speed bur + MTA-Angelus; Group 3: Ultrasonic retrotips + ProRoot MTA; Group 4: Ultrasonic retrotips + MTA-Angelus; Group 5: Er, Cr:YSGG laser tips + ProRoot MTA; Group 6: Er, Cr:YSGG laser tips + MTA-Angelus. Microleakage was measured using a fluid filtration technique. Differences in the fluid movement among groups were analyzed with a two-way analysis of variance (ANOVA) and LSD test. The results showed a significant difference between the groups prepared with laser and carbide bur (p < 0.05). No difference was found between root-end filling materials (p > 0.05). According to the results of the study, the cavities prepared with Er, Cr:YSGG laser demonstrated significantly lower microleakage in all the filling materials considered.


Assuntos
Coroas , Cárie Dentária/terapia , Infiltração Dentária/prevenção & controle , Lasers de Estado Sólido/uso terapêutico , Materiais Restauradores do Canal Radicular/química , Dente/química , Análise de Variância , Odontologia , Humanos , Técnicas In Vitro , Ápice Dentário
20.
IEEE Trans Pattern Anal Mach Intell ; 43(2): 663-678, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-31380747

RESUMO

SafePredict is a novel meta-algorithm that works with any base prediction algorithm for online data to guarantee an arbitrarily chosen correctness rate, 1-ϵ, by allowing refusals. Allowing refusals means that the meta-algorithm may refuse to emit a prediction produced by the base algorithm so that the error rate on non-refused predictions does not exceed ϵ. The SafePredict error bound does not rely on any assumptions on the data distribution or the base predictor. When the base predictor happens not to exceed the target error rate ϵ, SafePredict refuses only a finite number of times. When the error rate of the base predictor changes through time SafePredict makes use of a weight-shifting heuristic that adapts to these changes without knowing when the changes occur yet still maintains the correctness guarantee. Empirical results show that (i) SafePredict compares favorably with state-of-the-art confidence-based refusal mechanisms which fail to offer robust error guarantees; and (ii) combining SafePredict with such refusal mechanisms can in many cases further reduce the number of refusals. Our software is included in the supplementary material, which can be found on the Computer Society Digital Library at http://doi.ieeecomputersociety.org/10.1109/TPAMI.2019.2932415.

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