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1.
Sci Rep ; 14(1): 2683, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302503

RESUMO

TROP2 is a powerful cancer driver in colorectal cancer cells. Divergent epigenetic regulation mechanisms for the corresponding TACSTD2 gene exist such as miRNAs or DNA methylation. However, the role of TACSTD2 promoter hypermethylation in colorectal cancer has not been investigated yet. In this study, TROP2 expression strongly correlated with promoter methylation in different colorectal tumor cell lines. Treatment with 5-Azacytidine, a DNMT1 inhibitor, led to demethylation of the TACSTD2 promoter accompanied by an increase in TROP2 protein expression. TROP2 expression correlated with promoter methylation in vivo in human colon tumor tissue, thereby verifying promoter methylation as an important factor in the regulation of TROP2 expression in colorectal cancer. When performing a ChIP-Seq analysis in HCT116 and HT29 cells, we found that TACSTD2 promoter demethylation was accompanied by tri-methylation of H3K4. In silico analysis of GSE156613 data set confirmed that a higher binding of histone mark H3K4me3 around the TACSTD2 promoter was found in TACSTD2 high expressing tumors of colon cancer patients compared to the corresponding adjacent tumor tissue. Moreover, the link between TROP2 and the H3K4me3 code was even evident in tumors showing high intratumoral heterogeneity for TROP2 staining. Our data provide novel evidence for promoter demethylation and simultaneous gains of the active histone mark H3K4me3 across CpG-rich sequences, both being complementary mechanisms in the transcriptional regulation of TACSTD2 in colon cancer. The functional consequences of TROP2 loss in colorectal cancer needs to be further investigated.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Humanos , Epigênese Genética , Desmetilação do DNA , Metilação de DNA , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Colorretais/patologia , Ilhas de CpG , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo
2.
J Biol Phys ; 44(3): 419-431, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29796745

RESUMO

We measured temporal oscillations in thermodynamic variables such as temperature, heat flux, and cellular volume in suspensions of non-dividing yeast cells which exhibit temporal glycolytic oscillations. Oscillations in these variables have the same frequency as oscillations in the activity of intracellular metabolites, suggesting strong coupling between them. These results can be interpreted in light of a recently proposed theoretical formalism in which isentropic thermodynamic systems can display coupled oscillations in all extensive and intensive variables, reminiscent of adiabatic waves. This interpretation suggests that oscillations may be a consequence of the requirement of living cells for a constant low-entropy state while simultaneously performing biochemical transformations, i.e., remaining metabolically active. This hypothesis, which is in line with the view of the cellular interior as a highly structured and near equilibrium system where energy inputs can be low and sustain regular oscillatory regimes, calls into question the notion that metabolic processes are essentially dissipative.


Assuntos
Entropia , Glicólise , Modelos Biológicos , Saccharomyces cerevisiae/fisiologia , Temperatura Alta , Termodinâmica
3.
J Dairy Sci ; 101(7): 6066-6073, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29605323

RESUMO

The effects of dietary nonforage fiber sources on production responses of lactating dairy cattle have been well described, but interactions with other components of the diet have been less thoroughly explored. We investigated the effects of adding 2 commonly fed fat sources to a ration featuring high levels of nonforage fiber supplied by a corn milling by-product. Midlactation Holstein cows were blocked by parity, stratified by days in milk, and randomly assigned to 1 of 6 pens (12 cows/pen). Pens were randomly assigned to treatment sequences in a 3 × 3 Latin square design, where the treatments consisted of prilled saturated fat (SAT; Energy Booster 100, Milk Specialties Co., Dundee, IL), calcium salts of long-chain fatty acids (UNS; Megalac, Church and Dwight Co. Inc., Princeton, NJ), or no added dietary fat (control), with fat sources included to provide 1.2% added fat (dry matter basis). Treatment periods were 21 d; milk and feed samples were collected and milk yield and feed intake were recorded for the last 4 d of each period. Results were analyzed with mixed models with pen as the experimental unit, and orthogonal contrasts were employed to evaluate the overall effect of added fat and the effect of fat source. Dry matter intake and milk yield tended to increase with added fat. Protein content decreased with fat supplementation, to a greater degree for UNS than for SAT, but protein yield was not affected. Fat content, fat yield, and energy-corrected milk yield were not affected by treatment. Conversion of feed to milk tended to increase for UNS compared with SAT. Fat supplementation to diets high in nonforage fiber had effects that were similar to those reported for more traditional lactation diets, except for the dry matter intake response.


Assuntos
Bovinos , Dieta/veterinária , Gorduras na Dieta/administração & dosagem , Fibras na Dieta/administração & dosagem , Lactação/efeitos dos fármacos , Ração Animal , Animais , Feminino , Lactação/fisiologia , Leite , Rúmen , Zea mays
4.
J Exp Clin Cancer Res ; 36(1): 165, 2017 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-29169400

RESUMO

BACKGROUND: Human placental development resembles tumorigenesis, due to the invasive and fusogenic potential of trophoblasts. However, these features are tightly controlled in trophoblasts. Disturbance of this spatial and temporal regulation is thought to contribute to the rare formation of choriocarcinomas. Promoter hypermethylation and loss of the tumor suppressor Retinoic acid receptor responder 1 (RARRES1) were shown to contribute to cancer progression. Our study investigated the epigenetic and transcriptional regulation of RARRES1 in healthy human placenta in comparison to choriocarcinoma cell lines and cases. METHODS: Three choriocarcinoma cell lines (Jeg-3, JAR and BeWo) were treated with three different retinoic acid derivates (Am580, Tazarotene and all-trans retinoic acid) and 5-aza-2'-deoxycytidine. We analyzed RARRES1 promoter methylation by pyrosequencing and performed realtime-PCR quantification to determine RARRES1 expression in placental tissue and trophoblastic cell lines. Additionally, RARRES1 was stained in healthy placentas and in biopsies of choriocarcinoma cases (n = 10) as well as the first trimester trophoblast cell line Swan71 by immunofluorescence and immunohistochemistry. RESULTS: In the choriocarcinoma cell lines, RARRES1 expression could not be induced by sole retinoic acid treatment. Stimulation with 5-aza-2'-deoxycytidine significantly induced RARRES1 expression, which then could be further increased with Am580, Tazarotene and all-trans retinoic acid. In comparison to healthy placenta, choriocarcinoma cell lines showed a hypermethylation of the RARRES1 promoter, which correlated with a reduced RARRES1 expression. In concordance, RARRES1 protein expression was lost in choriocarcinoma tissue. Additionally, in the trophoblastic cell line Swan71, we found a significant induction of RARRES1 expression with increased cell density, during mitosis and in syncytial knots. CONCLUSIONS: Our findings showed that RARRES1 expression is absent in choriocarcinoma due to promoter methylation. Based on our analysis, we hypothesize that RARRES1 might exert tumor suppressive functions in multiple cellular processes (e.g. cell cycle regulation, adhesion, invasion and apoptosis).


Assuntos
Coriocarcinoma/genética , Metilação de DNA , Regulação para Baixo , Proteínas de Membrana/genética , Neoplasias Uterinas/genética , Linhagem Celular Tumoral , Coriocarcinoma/metabolismo , Progressão da Doença , Epigênese Genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas de Membrana/metabolismo , Gravidez , Regiões Promotoras Genéticas , Análise de Sequência de DNA , Neoplasias Uterinas/metabolismo
5.
J Anim Sci ; 95(8): 3639-3653, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28805922

RESUMO

Four experiments evaluated the use of a complete starter feed (RAMP; Cargill Corn Milling, Blair, NE) for grain adaptation. In Exp. 1, 229 yearling steers (397 ± 28.4 kg BW) were used to compare a traditional adaptation program (CON) with adapting cattle with RAMP in either a 1- (RAMP-1RS) or 2- (RAMP-2RS) ration system. From d 23 to slaughter, cattle were fed a common finishing diet. In Exp. 2, 390 yearling steers (341 ± 14 kg BW) were used to compare accelerated grain adaptation programs with RAMP with 2 control treatments where RAMP was blended with a finishing diet containing either 25 (CON25) or 47.5% (CON47) Sweet Bran (Cargill Corn Milling) in 4 steps fed over 24 d to adapt cattle. Rapid adaptation treatments involved feeding RAMP for 10 d followed by a blend of RAMP and a 47% Sweet Bran finishing diet to transition cattle with 3 blends fed for 1 d each (3-1d), 2 blends fed for 2 d each (2-2d), or 1 blend fed for 4 d (1-4d). From d 29 to slaughter, all cattle were fed a common finishing diet. In Exp. 3, 300 steer calves (292 ± 21 kg BW) were used to compare the CON47 and 1-4d adaptation programs with directly transitioning cattle from RAMP, which involved feeding RAMP for 10 d and then switching directly to F1 on d 11 (1-STEP). From d 29 until slaughter, F2 was fed to all cattle. In Exp. 4, 7 ruminally fistulated steers (482 ± 49 kg BW) were used in a 35-d trial to compare the CON47 and 1-STEP adaptation programs. Ruminal pH and intake data from the first 6 d of F1and first 6 d of F2 were used to compare adaptation systems. Adaptation with RAMP-1RS and RAMP-2RS increased ( < 0.01) G:F compared with cattle adapted using CON in Exp. 1. Feeding RAMP-1RS increased ADG ( = 0.03) compared with CON. Intakes were similar ( = 0.39) among treatments. Daily gain, DMI, G:F, and carcass traits were similar ( > 0.11) among treatments in Exp. 2. Daily gain, DMI, and G:F were not different ( > 0.20) among treatments on d 39 or over the entire feeding period in Exp. 3. When F1 or F2 was being fed, DMI was similar ( ≥ 0.40) for CON47 and 1-STEP in Exp. 4. When F1 or F2 was being fed, 1-STEP cattle had lower average ruminal pH ( ≤ 0.03) and greater time below a pH of 5.3 ( ≤ 0.03). Using RAMP for grain adaptation improved performance compared with traditional adaptation. Rapid adaptation with RAMP decreased pH, but no performance differences were observed between long and rapid RAMP adaptation programs. Therefore, cattle started on RAMP do not require extensive adaptation before feeding a finishing diet with Sweet Bran.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Dieta/veterinária , Adaptação Fisiológica , Criação de Animais Domésticos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Digestão , Grão Comestível , Masculino , Zea mays
6.
J Anim Sci ; 94(3): 1149-58, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27065276

RESUMO

Two trials evaluated adapting cattle to a finishing diet using wet corn gluten feed compared with traditional methods using forage. A 33-d grain adaptation metabolism trial (Exp. 1) compared decreasing wet corn gluten feed (Sweet Bran; Corn Milling unit, Cargill Corn Milling, Blair, NE) while increasing corn inclusion (SB) and a traditional grain adaptation system decreasing alfalfa hay while increasing corn with no Sweet Bran inclusion (CON). Ruminal pH, intake characteristics, and 24-h in situ digestibility were evaluated using 8 ruminally fistulated steers (291 kg BW [SD 19]). Steers (4/treatment) were adapted to finishing diets across 4 periods consisting of 5, 7, 7, and 7 d and then fed a finishing diet for 7 d. No period × adaptation diet interactions were observed ( ≥ 0.12). Average ruminal pH decreased ( < 0.01) whereas time and area below a pH of 5.6 increased ( ≤ 0.02) for the SB adaptation system compared with the CON adaptation system. Cattle adapted using SB had greater DMI than cattle adapted using CON ( < 0.01). As steers were adapted to finishing diets, DMI increased ( = 0.01), average ruminal pH decreased ( = 0.05), and time and area below a pH of 5.6 increased ( ≤ 0.04) for both treatments. Ruminal pH for CON steers decreased from 6.59 to 6.12 across periods as corn replaced alfalfa hay whereas ruminal pH decreased from 6.00 to 5.79 for SB steers. Steers adapted using SB had greater ( ≤ 0.05) in situ digestion of adaptation diets than steers adapted using CON for adaptation periods 3, 4, and 5. The SB diets were more digestible than the CON diets when incubated in either CON- or SB-fed steers for adaptation periods 1 and 2 ( < 0.01). Experiment 2 used 240 finishing steers (273 kg BW [SD 14]) to determine performance impacts of using Sweet Bran instead of forage to adapt cattle to finishing diets. Steers were fed either decreasing Sweet Bran inclusion while increasing corn (SB) or decreasing alfalfa hay inclusion while increasing corn (CON). Treatments were applied only during grain adaptation (26 d) and all steers were finished on a common diet containing 35% Sweet Bran for an additional 147 d. Steers adapted using SB had greater ( ≤ 0.01) final BW, ADG, G:F, and HCW compared with steers adapted using CON, even though treatments differed only the first 26 d. Grain adaptation treatment had no effect ( ≥ 0.13) on carcass quality. These results indicate that Sweet Bran can be used to adapt cattle to finishing diets instead of forage and improves ADG and G:F while decreasing the forage needs of feedlots.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Dieta/veterinária , Grão Comestível , Zea mays/química , Aclimatação , Criação de Animais Domésticos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Digestão
7.
Br J Cancer ; 110(12): 2985-95, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24853183

RESUMO

BACKGROUND: Oesophageal adenocarcinoma or Barrett's adenocarcinoma (EAC) is increasing in incidence and stratification of prognosis might improve disease management. Multi-colour fluorescence in situ hybridisation (FISH) investigating ERBB2, MYC, CDKN2A and ZNF217 has recently shown promising results for the diagnosis of dysplasia and cancer using cytological samples. METHODS: To identify markers of prognosis we targeted four selected gene loci using multi-colour FISH applied to a tissue microarray containing 130 EAC samples. Prognostic predictors (P1, P2, P3) based on genomic copy numbers of the four loci were statistically assessed to stratify patients according to overall survival in combination with clinical data. RESULTS: The best stratification into favourable and unfavourable prognoses was shown by P1, percentage of cells with less than two ZNF217 signals; P2, percentage of cells with fewer ERBB2- than ZNF217 signals; and P3, overall ratio of ERBB2-/ZNF217 signals. Median survival times for P1 were 32 vs 73 months, 28 vs 73 months for P2; and 27 vs 65 months for P3. Regarding each tumour grade P2 subdivided patients into distinct prognostic groups independently within each grade, with different median survival times of at least 35 months. CONCLUSIONS: Cell signal number of the ERBB2 and ZNF217 loci showed independence from tumour stage and differentiation grade. The prognostic value of multi-colour FISH-assays is applicable to EAC and is superior to single markers.


Assuntos
Adenocarcinoma/patologia , Esôfago de Barrett/patologia , Biomarcadores Tumorais/genética , Neoplasias Esofágicas/patologia , Hibridização in Situ Fluorescente/métodos , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Esôfago de Barrett/mortalidade , Inibidor p16 de Quinase Dependente de Ciclina/genética , DNA de Neoplasias/genética , Neoplasias Esofágicas/mortalidade , Feminino , Dosagem de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Proteínas Proto-Oncogênicas c-myc/genética , Receptor ErbB-2/genética , Transativadores/genética
9.
Br J Cancer ; 109(11): 2833-41, 2013 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-24196789

RESUMO

BACKGROUND: The detection of V600E BRAF mutations has fundamental clinical consequences as the treatment option with BRAF inhibitors such as vemurafenib or dabrafenib yields response rates of ~48%. Heterogeneity with respect to BRAF mutation in different metastases has been described in single cases. As this has important implications for the determination of BRAF status and treatment of patients, it is essential to acquire more data. METHODS: A total of 300 tumour samples from 187 melanoma patients were analysed for BRAF mutations by pyrosequencing. Equivocal results were confirmed by capillary sequencing. Clinical data with respect to melanoma type, tumour site and survival were summarised for 53 patients with multiple analysed tumour samples (2-13 per patient). RESULTS: BRAF mutations were found in 84 patients (44.9%) and 144 tumour samples (48%) with BRAF mutations in 45.5% of primary tumours and 51.3% of metastases, respectively. In 10 out of 53 patients (18.9%) where multiple samples were analysed results were discordant with respect to mutation findings with wild-type and mutated tumours in the same patient. Mutations did not appear more frequently over the course of disease nor was its occurrence associated with a specific localisation of metastases. CONCLUSION: As heterogeneity with respect to BRAF mutation status is detected in melanoma patients, subsequent testing of initially wild-type patients can yield different results and thus make BRAF inhibitor therapy accessible. The role of heterogeneity in testing and for clinical response to therapy with a BRAF inhibitor needs to be further investigated.


Assuntos
Heterogeneidade Genética , Melanoma/genética , Mutação de Sentido Incorreto , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Substituição de Aminoácidos , Análise Mutacional de DNA/métodos , Feminino , Frequência do Gene , Humanos , Masculino , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Análise de Sobrevida
10.
Br J Cancer ; 108(10): 2164-71, 2013 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-23579220

RESUMO

BACKGROUND: The detection of V600E BRAF mutation in melanoma is fundamental since here BRAF inhibitors represent an effective treatment. Non-V600E BRAF mutations that may also respond are not detected by certain screening methods. Thus, knowledge about detection of these mutations is needed. METHODS: A total of 276 tumour samples from 174 melanoma patients were investigated for BRAF mutations by pyrosequencing. Rare mutations were confirmed by capillary sequencing and compared with findings from COBAS test and immunohistochemistry using a novel BRAF antibody. Melanoma type, localisation, and survival were summarised. RESULTS: BRAF mutations were found in 43% of patients (124 tumours in 75 patients). Among those, 14 patients (18.7%) exhibited rare mutations. The V600EK601del and V600DK601del mutations have never been described before in melanoma. Furthermore, V600K, V600E2, and V600D, V600G, V600R, and L597S mutations were detected. Mutations were not detected by COBAS test in 7 out of these 14 patients and immunohistochemistry only reliably detected patients with the V600E2 and V600EK601del mutation. CONCLUSION: Accurate diagnosis of rare BRAF mutations is crucial. We show that pyrosequencing is accurate, highly sensitive, reliable, and time saving to detect rare BRAF mutations. Missing these rare variant mutations would exclude a subset of patients from available effective BRAF-targeting therapy.


Assuntos
Testes Genéticos , Melanoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Análise Mutacional de DNA/métodos , Feminino , Frequência do Gene , Células HCT116 , Células HT29 , Humanos , Masculino , Melanoma/diagnóstico , Melanoma/tratamento farmacológico , Melanoma/epidemiologia , Pessoa de Meia-Idade , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/epidemiologia
12.
Br J Cancer ; 107(4): 675-83, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22814582

RESUMO

BACKGROUND: Colon cancer predisposition is associated with mutations in BRCA1. BRCA1 protein stability depends on binding to BARD1. In different cancers, expression of differentially spliced BARD1 isoforms is correlated with poor prognosis and decreased patient survival. We therefore suspected a role of BARD1 isoforms in colon cancer. METHODS: We performed immunohistochemistry in 168 colorectal cancers, using four antibodies directed against differentially expressed regions of BARD1. We determined structure and relative expression of BARD1 mRNA isoforms in 40 tumour and paired normal peri-tumour tissues. BARD1 expression was correlated with clinical outcome. RESULTS: BARD1 isoforms were expressed in 98% of cases and not correlated with BRCA1. BARD1 mRNA isoforms were upregulated in all tumours as compared with paired normal peri-tumour tissues. Non-correlated expression and localisation of different epitopes suggested insignificant expression of full-length (FL) BARD1. Expression of N- and C-terminal epitopes correlated with increased survival, but expression of epitopes mapping to the middle of BARD1 correlated with decreased survival. Middle epitopes are present in oncogenic BARD1 isoforms, which have pro-proliferative functions. Correlated upregulation of only N- and C-terminal epitopes reflects the expression of isoforms BARD1δ and BARD1φ. CONCLUSION: Our results suggest that BARD1 isoforms, but not FL BARD1, are expressed in colon cancer and affect its progression and clinical outcome.


Assuntos
Neoplasias do Colo/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína BRCA1/metabolismo , Neoplasias do Colo/mortalidade , Neoplasias do Colo/patologia , Neoplasias Colorretais/metabolismo , Metilação de DNA , Progressão da Doença , Mapeamento de Epitopos , Estrogênios/farmacologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Resultado do Tratamento , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Regulação para Cima
13.
Clin Exp Metastasis ; 29(8): 889-900, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22552371

RESUMO

We investigated the methylation status of mismatch repair gene hMLH1 in 80 primary human endometrial carcinomas (ECs) and in 30 metastatic lesions. It was correlated to the expression of hMLH1 protein, microsatellite instability (MSI) of ECs and to the well-known clinico-pathological variables of cancer. The hMLH1 promoter methylation was detected in 24 out of 64 (37.5 %) primary ECs but only in one out of 18 (5.6 %) metastatic lesions investigated. Promoter hMLH1 hypermethylation was found more often in early stage ECs and was associated with a decrease of hMLH1 protein expression immunohistochemically. An inverse relationship between hMLH1 expression and clinical stage of the disease was found (p = 0.048). Interestingly, there was a significant correlation between MSI and hMLH1 protein expression level (p = 0.042). MSI phenotype was found more often in EC metastases compared to the primary tumors (66.7 % vs 29.3 %; p = 0.039). However, neither hMLH1 promoter hypermethylation nor MSI was independent predictive factors for patient's outcome. Using an in vitro model we showed that hMLH1 methylation is reversible. These data showed that hMLH1 methylation with a consequent protein decrease occurred early during EC tumorigenesis and may cause a MSI phenotype, which occurs relatively late. MSI may be an important mechanism supporting further the tumor progression. These findings may have importance for the specific chemosensitization of the primary tumors/metastases and can improve our understanding of endometrial carcinogenesis in humans.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Metilação de DNA , Enzimas Reparadoras do DNA/metabolismo , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Instabilidade de Microssatélites , Metástase Neoplásica/genética , Proteínas Nucleares/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Azacitidina/farmacologia , Linhagem Celular Tumoral , Metilação de DNA/efeitos dos fármacos , Reparo do DNA , Enzimas Reparadoras do DNA/genética , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/mortalidade , Feminino , Humanos , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Gradação de Tumores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/genética , Fenótipo , Prognóstico , Regiões Promotoras Genéticas
14.
Bull Soc Pathol Exot ; 105(3): 157-61, 2012 Aug.
Artigo em Francês | MEDLINE | ID: mdl-22359185

RESUMO

An open, pragmatic, phase IV clinical trial was undertaken to measure tolerance and assess the effectiveness of Antivipmyn® Africa, antivenom composed of lyophilized F(ab')(2) fragments of immunoglobulin G in field conditions. The study was conducted at the Institut Pasteur of Guinea (IPG) from August 2009 to February 2010. Two hundred twenty-eight victims of snakebites presented at the processing center of the IPG during this period, including one hundred fifty (65.8%) envenomations, mostly young men. One hundred twenty-four of them (82.7%) suffered from viper envenomations and 26 (17.3%) from elapid ones. All patients were treated by intravenous Antivipmyn® Africa, averaging 1.4 (± 1.0) vials, more in patients with neurotoxic envenomation than others (P < 10(-5)). Four patients (2.7%), showing cobralike envenomation, died shortly after their arrival at the IPG despite the administration of the antivenom. Ten patients showed mild side effects (rash or pruritus), out of which 5 (3.3%) were probably due to treatment. This study confirms the efficacy and safety of Antivipmyn® Africa.


Assuntos
Antivenenos/uso terapêutico , Fragmentos Fab das Imunoglobulinas/uso terapêutico , Mordeduras de Serpentes/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antivenenos/efeitos adversos , Criança , Pré-Escolar , Diagnóstico Tardio/estatística & dados numéricos , Feminino , Guiné/epidemiologia , Humanos , Fragmentos Fab das Imunoglobulinas/efeitos adversos , Lactente , Masculino , Pessoa de Meia-Idade , Mordeduras de Serpentes/diagnóstico , Mordeduras de Serpentes/epidemiologia , Venenos de Serpentes/imunologia , Resultado do Tratamento , Adulto Jovem
15.
J Neurooncol ; 107(3): 503-16, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22270849

RESUMO

Glioblastomas are known to be highly chemoresistant, but HDAC inhibitors (HDACi) have been shown to be of therapeutic relevance for this aggressive tumor type. We treated U87 glioblastoma cells with trichostatin A (TSA) to define potential epigenetic targets for HDACi-mediated antitumor effects. Using a cDNA array analysis covering 96 cell cycle genes, cyclin-dependent kinase inhibitor p21(WAF1) was identified as the major player in TSA-induced cell cycle arrest. TSA slightly inhibited proliferation and viability of U87 cells, cumulating in a G1/S cell cycle arrest. This effect was accompanied by a significant up-regulation of p53 and its transcriptional target p21(WAF1) and by down-regulation of key G1/S regulators, such as cdk4, cdk6, and cyclin D1. Nevertheless, TSA did not induce apoptosis in U87 cells. As expected, TSA promoted the accumulation of total acetylated histones H3 and H4 and a decrease in endogenous HDAC activity. Characterizing the chromatin modulation around the p21(WAF1) promoter after TSA treatment using chromatin immunoprecipitation, we found (1) a release of HDAC1, (2) an increase of acetylated H4 binding, and (3) enhanced recruitment of p53. p53-depleted U87 cells showed an abrogation of the G1/S arrest and re-entered the cell cycle. Immunofluorescence staining revealed that TSA induced the nuclear translocation of p21(WAF1) verifying a cell cycle arrest. On the other hand, a significant portion of p21(WAF1) was present in the cytoplasmic compartment causing apoptosis resistance. Furthermore, TSA-treated p53-mutant cell line U138 failed to show an induction in p21(WAF1), showed a deficient G2/M checkpoint, and underwent mitotic catastrophe. We suggest that HDAC inhibition in combination with other clinically used drugs may be considered an effective strategy to overcome chemoresistance in glioblastoma cells.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glioblastoma/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Citometria de Fluxo , Imunofluorescência , Perfilação da Expressão Gênica , Glioblastoma/genética , Humanos , Immunoblotting , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Supressora de Tumor p53/genética
16.
Bull Soc Pathol Exot ; 105(3): 194-8, 2012 Aug.
Artigo em Francês | MEDLINE | ID: mdl-22006245

RESUMO

The authors present a summary of the proceedings and the recommendations of the Fourth International Conference on Envenomations by Snakebites and Scorpion Stings in Africa, held from 25 to 29 April 2011 in Dakar. After a two-day workshop for Senegalese health personnel on the most relevant aspects of the management of envenomations, about 270 participants met to share their experiences in the field. Nearly a hundred oral and poster presentations were made on the epidemiology of snakebites and scorpion stings in Africa, the composition and action of venoms and the manufacture and use of antivenoms. The last day was devoted to an institutional debate involving experts, representatives of national health authorities and concerned professionals (physicians, pharmacists, nurses and traditional healers) as well as members of the pharmaceutical industry to discuss and elaborate a set of recommendations. It was agreed that it is necessary to improve knowledge of the epidemiological situation by case reporting. Quality control of antivenoms and procedures for their registration at the level of national health authorities should aim at improving the distribution of safe and effective antivenoms in peripheral health centers for the better assessment of victims. It was also recommended that adequate training should be provided for health personnel in all aspects of medical management of envenomations. Equitable distribution of funding and the establishment of a network of African experts were also discussed in the conference.


Assuntos
Congressos como Assunto , Picadas de Escorpião , Escorpiões , Mordeduras de Serpentes , África/epidemiologia , Animais , Antivenenos/uso terapêutico , Mordeduras e Picadas/epidemiologia , Mordeduras e Picadas/terapia , Humanos , Cooperação Internacional , Guias de Prática Clínica como Assunto , Picadas de Escorpião/epidemiologia , Picadas de Escorpião/terapia , Venenos de Escorpião/imunologia , Escorpiões/anatomia & histologia , Escorpiões/imunologia , Senegal/epidemiologia , Mordeduras de Serpentes/epidemiologia , Mordeduras de Serpentes/terapia , Venenos de Serpentes/imunologia , Serpentes/anatomia & histologia , Serpentes/imunologia
18.
J Anim Sci ; 88(3): 1061-72, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19966168

RESUMO

Three experiments were conducted to evaluate the use of combinations of wet corn gluten feed (WCGF) and wet distillers grain plus solubles (WDGS) in dry-rolled and high-moisture corn-based finishing diets for beef cattle. In Exp. 1, 250 steers (BW = 343 +/- 13.5 kg) were fed 5 treatments consisting of a corn-based, control diet with 0% coproducts, and diets including 30% WCGF, 30% WDGS, 15% WCGF plus 15% WDGS, or 30% WCGF plus 30% WDGS. No associative effects resulted from feeding 15% WCGF plus 15% WDGS; DMI, ADG, and G:F were intermediate between steers fed WCGF or WDGS at 30% of diet DM. Feeding coproducts in combinations at 30 and 60% of diet DM increased ADG, G:F, and final BW (P < 0.05) compared with the corn-based diet. In Exp. 2, 280 yearling steers (BW = 370 +/- 0.45 kg) were used to evaluate feeding 0, 25, 50, or 75% coproducts as a combination of 50% WCGF:50% WDGS (DM basis). Additional diets were fed containing decreased alfalfa hay at 5, 2.5, and 0% (DM basis) as coproduct blend inclusions increased at 25, 50, and 75% (DM basis), respectively. No interactions were observed between alfalfa hay and coproduct blend levels, and no effects on ADG or G:F (P > 0.21) were observed due to alfalfa hay. Intake, ADG, and G:F responded quadratically (P < 0.05) across coproduct levels, with the greatest ADG and G:F at 25 and 50% blend, and similar ADG and G:F for the 0 and 75% blend levels. In Exp. 3, 504 steers (BW = 376 +/- 16 kg) were fed to evaluate 0, 10, 15, 20, 25, and 30% (DM basis) WDGS in diets containing 30% WCGF (DM basis) as well as a control diet with no coproducts. The inclusion of 30% WCGF in the diets increased DMI, ADG, and G:F (P < 0.05) when compared with control. Response to inclusion level of WDGS tended to be quadratic for DMI (P = 0.12), quadratic for ADG (P = 0.05), and no effect for G:F (P = 0.96). Greatest ADG was achieved with 15 to 20% WDGS inclusion in diets containing 30% WCGF. The use of combinations of WCGF and WDGS in finishing diets resulted in similar or improved steer performance compared with corn, suggesting replacement of corn with coproduct combinations up to 75% diet DM is possible if a roughage source is fed.


Assuntos
Ração Animal , Bovinos/fisiologia , Dieta/veterinária , Animais , Peso Corporal/fisiologia , Bovinos/metabolismo , Grão Comestível , Glutens , Masculino , Valor Nutritivo , Zea mays
19.
Pathologe ; 31(2): 115-22, 2010 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-19949796

RESUMO

The discovery of activating oncogenic C-KIT and PDGFRA mutations in gastrointestinal stromal tumors (GIST) represented the key for the development of innovative targeted molecular therapy using the tyrosine kinase inhibitors (TKI) Imatinib (Glivec(R)), Sunitinib and other substances. This makes a precise histopathological diagnosis a major prerequisite, supplemented by appropriate risk stratification for the assessment of the expected biological behavior of individual tumors. Current knowledge demonstrates that the presence of kinase mutations in C-KIT and PDGFRA and their localization within the gene sequence as well as the mutation type are of great importance for planning appropriate treatment (drug selection and dose recommendation), but also for the assessment of prognosis and explanation of secondary resistance to TKI after initial response. This article gives an overview on current developments in the histopathological and molecular diagnostics of GIST and the role of kinase mutation analysis for optimizing patient treatment.


Assuntos
Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos , Tumores do Estroma Gastrointestinal/patologia , Indóis/uso terapêutico , Piperazinas/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Benzamidas , Análise Mutacional de DNA , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/genética , Trato Gastrointestinal/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Mesilato de Imatinib , Prognóstico , Proteínas Proto-Oncogênicas c-kit/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Análise de Sequência de DNA , Sunitinibe
20.
Phys Rev Lett ; 102(25): 250404, 2009 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-19659060

RESUMO

We analyze the relationship between tripartite entanglement and genuine tripartite nonlocality for three-qubit pure states in the Greenberger-Horne-Zeilinger class. We consider a family of states known as the generalized Greenberger-Horne-Zeilinger states and derive an analytical expression relating the three-tangle, which quantifies tripartite entanglement, to the Svetlichny inequality, which is a Bell-type inequality that is violated only when all three qubits are nonlocally correlated. We show that states with three-tangle less than 1/2 do not violate the Svetlichny inequality. On the other hand, a set of states known as the maximal slice states does violate the Svetlichny inequality, and exactly analogous to the two-qubit case, the amount of violation is directly related to the degree of tripartite entanglement. We discuss further interesting properties of the generalized Greenberger-Horne-Zeilinger and maximal slice states.

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