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1.
Bioengineering (Basel) ; 11(2)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38391650

RESUMO

Transforaminal lumbar interbody fusion (TLIF) is a commonly used technique for treating lumbar degenerative diseases. In this study, we developed a fully computer-supported pipeline to predict both the cage height and the degree of lumbar lordosis subtraction from the pelvic incidence (PI-LL) after TLIF surgery, utilizing preoperative X-ray images. The automated pipeline comprised two primary stages. First, the pretrained BiLuNet deep learning model was employed to extract essential features from X-ray images. Subsequently, five machine learning algorithms were trained using a five-fold cross-validation technique on a dataset of 311 patients to identify the optimal models to predict interbody cage height and postoperative PI-LL. LASSO regression and support vector regression demonstrated superior performance in predicting interbody cage height and postoperative PI-LL, respectively. For cage height prediction, the root mean square error (RMSE) was calculated as 1.01, and the model achieved the highest accuracy at a height of 12 mm, with exact prediction achieved in 54.43% (43/79) of cases. In most of the remaining cases, the prediction error of the model was within 1 mm. Additionally, the model demonstrated satisfactory performance in predicting PI-LL, with an RMSE of 5.19 and an accuracy of 0.81 for PI-LL stratification. In conclusion, our results indicate that machine learning models can reliably predict interbody cage height and postoperative PI-LL.

2.
J Neurosci ; 44(4)2024 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-38124193

RESUMO

K+-Cl- cotransporter-2 (KCC2) critically controls neuronal chloride homeostasis and maintains normal synaptic inhibition by GABA and glycine. Nerve injury diminishes synaptic inhibition in the spinal cord via KCC2 impairment. However, how KCC2 regulates nociceptive input to spinal excitatory and inhibitory neurons remains elusive. Here, we show that basal GABA reversal potentials were significantly more depolarized in vesicular GABA transporter (VGAT)-expressing inhibitory neurons than those in vesicular glutamate transporter-2 (VGluT2)-expressing excitatory neurons in spinal cords of male and female mice. Strikingly, inhibiting KCC2 with VU0463271 increased currents elicited by puff NMDA and the NMDAR-mediated frequency of mEPSCs in VGluT2, but not in VGAT, dorsal horn neurons. Notably, VU0463271 had no effect on EPSCs monosynaptically evoked from the dorsal root in VGluT2 neurons. Furthermore, VU0463271 augmented α2δ-1-NMDAR interactions and their protein levels in spinal cord synaptosomes. In Cacna2d1 KO mice, VU0463271 had no effect on puff NMDA currents or the mEPSC frequency in dorsal horn neurons. Disrupting α2δ-1-NMDAR interactions with α2δ-1 C-terminus mimicking peptide diminished VU0463271-induced potentiation in the mEPSC frequency and puff NMDA currents in VGluT2 neurons. Additionally, intrathecal injection of VU0463271 reduced mechanical and thermal thresholds in wild-type mice, but not in Cacna2d1 KO mice. VU0463271-induced pain hypersensitivity in mice was abrogated by co-treatment with the NMDAR antagonist, pregabalin (an α2δ-1 inhibitory ligand), or α2δ-1 C-terminus mimicking peptide. Our findings suggest that KCC2 controls presynaptic and postsynaptic NMDAR activity specifically in excitatory dorsal horn neurons. KCC2 impairment preferentially potentiates nociceptive transmission between spinal excitatory interneurons via α2δ-1-bound NMDARs.Significance statementImpaired function of potassium-chloride cotransporter-2 (KCC2), a key regulator of neuronal inhibition, in the spinal cord plays a major role in neuropathic pain. This study unveils that KCC2 controls spinal nociceptive synaptic strength via NMDA receptors in a cell type- and synapse type-specific manner. KCC2 inhibition preferentially augments presynaptic and postsynaptic NMDA receptor activity in spinal excitatory interneurons via α2δ-1 (previously known as a calcium channel subunit). Importantly, spinal KCC2 impairment triggers pain hypersensitivity through α2δ-1-coupled NMDA receptors. These findings pinpoint the cell and molecular substrates for the reciprocal relationship between spinal synaptic inhibition and excitation in chronic neuropathic pain. Targeting both KCC2 and α2δ-1­NMDA receptor complexes could be an effective strategy in managing neuropathic pain conditions.


Assuntos
Receptores de N-Metil-D-Aspartato , Simportadores , Animais , Feminino , Masculino , Camundongos , Ácido gama-Aminobutírico/metabolismo , N-Metilaspartato/farmacologia , Peptídeos/farmacologia , Células do Corno Posterior/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Medula Espinal/metabolismo , Simportadores/genética , Simportadores/metabolismo , Sinapses/metabolismo
3.
Materials (Basel) ; 15(3)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35160723

RESUMO

The present work extends the examination of selective laser melting (SLM)-fabricated 15-5 PH steel with the 8%-transient-austenite-phase towards fully-reversed strain-controlled low-cycle fatigue (LCF) test. The cyclic-deformation response and microstructural evolution were investigated via in-situ neutron-diffraction measurements. The transient-austenite-phase rapidly transformed into the martensite phase in the initial cyclic-hardening stage, followed by an almost complete martensitic transformation in the cyclic-softening and steady stage. The compressive stress was much greater than the tensile stress at the same strain amplitude. The enhanced martensitic transformation associated with lower dislocation densities under compression predominantly governed such a striking tension-compression asymmetry in the SLM-built 15-5 PH.

4.
Am Nat ; 199(2): E28-E42, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35077272

RESUMO

AbstractCetaceans (whales, dolphins, and porpoises) have undergone a radical transformation from the typical terrestrial mammalian body plan to a streamlined body, while exhibiting dramatic interspecific size differences. However, the molecular mechanisms underlying the diversification of cetacean body size are largely unknown. Here, by using genomic and phenotypic data for 22 cetaceans, we performed phylogenetic genome-body size analysis and explored the genetic basis of the high diversity of body size in cetaceans. A functional enrichment analysis showed that body size-related genes in cetaceans are enriched in pathways associated with immunity, cell growth, and metabolism, suggesting that they contributed to body size diversification. Genes showing correlated evolution with body size were mainly involved in immune surveillance, tumor suppression function, and development of hypertumors. The role of these genes in tumor control resolves Peto's paradox (i.e., the lack of a correspondence between an expansion in body size and, thereby, cell number and an increased cancer incidence). Our results provide novel insights into the evolution of substantial body size variation in cetaceans.


Assuntos
Genoma , Neoplasias , Animais , Tamanho Corporal/genética , Evolução Molecular , Genômica , Mamíferos/genética , Neoplasias/genética , Filogenia
5.
Sci Rep ; 11(1): 9610, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953260

RESUMO

We demonstrated the design of pre-additive manufacturing microalloying elements in tuning the microstructure of iron (Fe)-based alloys for their tunable mechanical properties. We tailored the microalloying stoichiometry of the feedstock to control the grain sizes of the metallic alloy systems. Two specific microalloying stoichiometries were reported, namely biodegradable iron powder with 99.5% purity (BDFe) and that with 98.5% (BDFe-Mo). Compared with the BDFe, the BDFe-Mo powder was found to have lower coefficient of thermal expansion (CTE) value and better oxidation resistance during consecutive heating and cooling cycles. The selective laser melting (SLM)-built BDFe-Mo exhibited high ultimate tensile strength (UTS) of 1200 MPa and fair elongation of 13.5%, while the SLM-built BDFe alloy revealed a much lower UTS of 495 MPa and a relatively better elongation of 17.5%, indicating the strength enhancement compared with the other biodegradable systems. Such an enhanced mechanical behavior in the BDFe-Mo was assigned to the dominant mechanism of ferrite grain refinement coupled with precipitate strengthening. Our findings suggest the tunability of outstanding strength-ductility combination by tailoring the pre-additive manufacturing microalloying elements with their proper concentrations.

6.
J Alloys Compd ; 857: 157555, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33071463

RESUMO

In-situ thermal cycling neutron diffraction experiments were employed to unravel the effect of thermal history on the evolution of phase stability and internal stresses during the additive manufacturing (AM) process. While the fully-reversible martensite-austenite phase transformation was observed in the earlier thermal cycles where heating temperatures were higher than Af, the subsequent damped thermal cycles exhibited irreversible phase transformation forming reverted austenite. With increasing number of thermal cycles, the thermal stability of the retained austenite increased, which decreased the coefficient of thermal expansion. However, martensite revealed higher compressive residual stresses and lower dislocation density, indicating inhomogeneous distributions of the residual stresses and microstructures on the inside and on the surface of the AM component. The compressive residual stresses that acted on the martensite resulted preferentially from transformation strain and additionally from thermal misfit strain, and the decrease in the dislocation density might have been due to the strong recovery effect near the Ac1 temperature.

7.
Clin Radiol ; 75(10): 797.e9-797.e19, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32703542

RESUMO

AIM: To evaluate contrast medium delivery protocols for the optimal enhancement profile of the aorta with both a reduced dose of radiation and contrast medium, called double-low computed tomography (CT) angiography (DLCTA). MATERIALS AND METHODS: DLCTA was performed with 70 kVp and 200 mg iodine/kg in 205 patients following four protocols, namely slow rate (n=52), short duration (n=52), low concentration (n=50), and combined method (n=51), in comparison with a conventional group (120 kVp, 400 mg iodine/kg, n=51). The quantitative measurement of aortic attenuation, homogeneity, and subjective scores were evaluated. RESULTS: Overall, in the four DLCTA groups, the radiation dose was reduced by 62%, and the iodine dose was reduced by 50%. Among the four DLCTA groups, the signal to noise ratio (SNR) and contrast to noise ratio (CNR) of the thoracic aorta were similar, but a significant difference was noted in the abdominal aorta. The short-duration group had the highest peak enhancement, least homogeneity, and worst subjective scores. Good contrast enhancement and good homogeneity were significantly more frequent in the slow-rate (86.6% and 90.4%, respectively) and low-concentration groups (78% and 96.0%, respectively). Subjective scores exhibited a trend of higher scores in the low-concentration group and lower scores in the slow-rate group (p=0.071). CONCLUSION: DLCTA with 70 kVp and 200 mg iodine/kg is feasible for whole-aortic CT angiography. The low-concentration protocol is recommended owing to its most consistent optimal aortic enhancement profile. Alternatively, the slow-rate protocol can be considered for patients with limited venous access.


Assuntos
Doenças da Aorta/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste/administração & dosagem , Iohexol/administração & dosagem , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador , Razão Sinal-Ruído
8.
Pediatr Surg Int ; 35(8): 829-834, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31201486

RESUMO

Although most children with Hirschsprung disease ultimately achieve functional and comfortable stooling, some will experience a variety of problems after pull-through surgery. The most common problems include soiling, obstructive symptoms, enterocolitis, and failure to thrive. The purpose of this guideline is to present a rational approach to the management of postoperative soiling in children with Hirschsprung disease. The American Pediatric Surgical Association Hirschsprung Disease Interest Group engaged in a literature review and group discussions. Expert consensus was then used to summarize the current state of knowledge regarding causes, methods of diagnosis, and treatment approaches to children with soiling symptoms following pull-through for Hirschsprung disease. Causes of soiling after pull-through are broadly categorized as abnormalities in sensation, abnormalities in sphincter control, and "pseudo-incontinence." A stepwise algorithm for the diagnosis and management of soiling after a pull-through for Hirschsprung disease is presented; it is our hope that this rational approach will facilitate treatment and optimize outcomes.


Assuntos
Algoritmos , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Incontinência Fecal/cirurgia , Doença de Hirschsprung/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Guias de Prática Clínica como Assunto , Criança , Incontinência Fecal/etiologia , Doença de Hirschsprung/complicações , Humanos , Período Pós-Operatório , Resultado do Tratamento
9.
Materials (Basel) ; 12(6)2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30934617

RESUMO

In this study, we demonstrate the fabrication of Y-doped bioactive glass (BG), which is proposed as a potential material for selective internal radiotherapy applications. Owing to its superior bioactivity and biodegradability, it overcomes the problem of yttrium aluminosilicate spheres that remain in the host body for a long duration after treatment. The preparation of Y-doped BG powders were carried out using a spray pyrolysis method. By using two different yttrium sources, we examine the change of the local distribution of yttrium concentration. In addition, characterizations of phase information, particle morphologies, surface areas, and bioactivity were also performed. The results show that both Y-doped BG powders are bioactive and the local Y distribution can be controlled.

10.
Fa Yi Xue Za Zhi ; 33(3): 284-288, 2017 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-29230996

RESUMO

Due to the negative autopsy and without cardiac structural abnormalities, unexpected sudden cardiac death (USCD) is always a tough issue for forensic pathological expertise. USCD may be associated with parts of fatal arrhythmic diseases. These arrhythmic diseases may be caused by disorders of cardiac ion channels or channel-related proteins. Caveolin can combine with multiple myocardial ion channel proteins through its scaffolding regions and plays an important role in maintaining the depolarization and repolarization of cardiac action potential. When the structure and function of caveolin are affected by gene mutations or abnormal protein expression, the functions of the regulated ion channels are correspondingly impaired, which leads to the occurrence of multiple channelopathies, arrhythmia or even sudden cardiac death. It is important to study the effects of caveolin on the functions of ion channels for exploring the mechanisms of malignant arrhythmia and sudden cardiac death.


Assuntos
Arritmias Cardíacas/fisiopatologia , Caveolinas/metabolismo , Canalopatias/genética , Canais Iônicos/metabolismo , Arritmias Cardíacas/genética , Arritmias Cardíacas/metabolismo , Autopsia , Canalopatias/complicações , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/patologia , Patologia Legal , Humanos , Canais Iônicos/genética , Mutação , Miocárdio
11.
Cell Death Dis ; 7: e2161, 2016 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-27031958

RESUMO

Methamphetamine (METH) abuse has been a serious global public health problem for decades. Previous studies have shown that METH causes detrimental effects on the nervous and cardiovascular systems. METH-induced cardiovascular toxicity has been, in part, attributed to its destructive effect on vascular endothelial cells. However, the underlying mechanism of METH-caused endothelium disruption has not been investigated systematically. In this study, we identified a novel pathway involved in endothelial cell apoptosis induced by METH. We demonstrated that exposure to METH caused mitochondrial apoptosis in human umbilical vein endothelial cells and rat cardiac microvascular endothelial cells in vitro as well as in rat cardiac endothelial cells in vivo. We found that METH mediated endothelial cell apoptosis through Nupr1-Chop/P53-PUMA/Beclin1 signaling pathway. Specifically, METH exposure increased the expression of Nupr1, Chop, P53 and PUMA. Elevated p53 expression raised up PUMA expression, which initiated mitochondrial apoptosis by downregulating antiapoptotic Bcl-2, followed by upregulation of proapoptotic Bax, resulting in translocation of cytochrome c (cyto c), an apoptogenic factor, from the mitochondria to cytoplasm and activation of caspase-dependent pathways. Interestingly, increased Beclin1, upregulated by Chop, formed a ternary complex with Bcl-2, thereby decreasing the dissociative Bcl-2. As a result, the ratio of dissociative Bcl-2 to Bax was also significantly decreased, which led to translocation of cyto c and initiated more drastic apoptosis. These findings were supported by data showing METH-induced apoptosis was significantly inhibited by silencing Nupr1, Chop or P53, or by PUMA or Beclin1 knockdown. Based on the present data, a novel mechanistic model of METH-induced endothelial cell toxicity is proposed. Collectively, these results highlight that the Nupr1-Chop/P53-PUMA/Beclin1 pathway is essential for mitochondrion-related METH-induced endothelial cell apoptosis and may be a potential therapeutic target for METH-caused cardiovascular toxicity. Future studies using knockout animal models are warranted to substantiate the present findings.


Assuntos
Apoptose/efeitos dos fármacos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Metanfetamina/toxicidade , Mitocôndrias/metabolismo , Proteínas de Neoplasias/metabolismo , Fator de Transcrição CHOP/metabolismo , Animais , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/antagonistas & inibidores , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteína Beclina-1/antagonistas & inibidores , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Linhagem Celular , Estimulantes do Sistema Nervoso Central/toxicidade , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição CHOP/antagonistas & inibidores , Fator de Transcrição CHOP/genética , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo
12.
Parasite Immunol ; 37(9): 470-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26178310

RESUMO

Activation of macrophages is a key step in the initiation of immune responses, but the transcriptional mechanisms governing macrophage activation during infection are not fully understood. It was recently shown that the AP-1 family transcription factor JUNB positively regulates macrophage activation in response to Toll-like receptor agonists that promote classical or M1 polarization, as well as to the cytokine interleukin-4 (IL-4), which elicits an alternatively activated or M2 phenotype. However, a role for JUNB in macrophage activation has never been demonstrated in vivo. Here, to dissect the role of JUNB in macrophage activation in a physiological setting, mice lacking JUNB specifically in myeloid cells were tested in two infection models: experimental cerebral malaria, which elicits a pathological type 1 immune response, and helminth infection, in which type 2 responses are protective. Myeloid-restricted deletion of Junb reduced type 1 immune activation, which was associated with reduced cerebral pathology and improved survival during infection with Plasmodium berghei. Myeloid JUNB deficiency also compromised type 2 activation during infection with the hookworm Nippostrongylus brasiliensis, leading to diminished cytokine production and eosinophil recruitment and increased parasite burden. These results demonstrate that JUNB in myeloid cells shapes host responses and outcomes during type 1 and type 2 infections.


Assuntos
Malária/imunologia , Plasmodium berghei/fisiologia , Infecções por Strongylida/imunologia , Fatores de Transcrição/metabolismo , Animais , Citocinas/imunologia , Eosinófilos/imunologia , Ativação de Macrófagos , Macrófagos/imunologia , Malária Cerebral/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Nippostrongylus/imunologia , Células de Purkinje/fisiologia , Fator de Transcrição AP-1/metabolismo , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética
13.
Nutr Diabetes ; 5: e154, 2015 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-25915743

RESUMO

BACKGROUND: Alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD) are highly prevalent liver diseases that may coexist and contribute significantly to liver disease-related mortality. Obesity is a common underlying risk factor for both disorders. There has been little research investigating the combined effects of high fat diet (HFD) and alcohol. Current mouse models of alcohol- or fat-rich diet alone do not lead to severe liver injury. There is a need to develop animal models recapitulating human settings of drinking and diet to study the mechanisms of liver injury progression. METHODS: C57BL6 male mice were fed either chow or HFD ad libitum for 12 weeks. A sub-set of mice from each group were also given alcohol (2 g kg(-)(1) body weight) twice a week via intra-gastric lavage. Animals were monitored progressively for weight gain and blood and livers were harvested at termination. The extent of liver injury was examined by histopathology as well as by liver and serum biochemistry. The expression of lipid metabolism, inflammation and fibrogenesis-related molecules was examined by quantitative reverse transcription PCR (Q-PCR) and immunofluorescence staining. RESULTS: HFD significantly increased total body weight, triglyceride and cholesterol, whereas alcohol increased liver weight. Alcohol+HFD in combination produced maximum hepatic steatosis, increased micro- and macro-vesicular lipid droplets, increased de novo lipogenesis (steroid response-element binding protein 1 (SREBP-1) and stearoyl-CoA desaturase-1 (SCD-1)) and proliferation peroxisome activated receptor alpha (PPARα), and decreased fatty acid ß-oxidation (Acyl-CoA oxidase 1 (ACOX1)). Alcohol+HFD treatment also increased the inflammation (CD45+, CD68+, F4/80+ cells; tumour necrosis factor-alpha (TNF-α), F4/80 mRNAs) and fibrogenesis (vimentin+ activated stellate cells, collagen 1 (Col1) production, transforming growth factor-beta (TGF-ß) and Col-1 mRNAs) in mice livers. CONCLUSIONS: We report a novel mouse model with more severe liver injury than either alcohol or HFD alone recapitulating the human setting of intermittent alcohol drinking and HFD.

14.
Oncogene ; 34(10): 1263-9, 2015 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-24662822

RESUMO

The antineoplastic drug hydroxyurea (HU), when used at subtoxic doses, induces prolonged replication stress and centrosome amplification. This causes genomic instability and increases the malignancy of the recurring tumor. The mechanism of centrosome amplification induced by prolonged replication stress, however, is still unclear. Here, we examined the involvement of ataxia telangiectasia, mutated (ATM), ataxia telangiectasia, mutated and Rad3-related (ATR) and DNA-dependent protein kinase (DNA-PK) and found that HU-induced centrosome amplification was inhibited by the depletion of DNA-PKcs, but not ATM and ATR. Inactivation of ATM/ATR in U2OS cells instead caused aneuploidy and cell death. We found DNA-PKcs depletion also abrogated ATM phosphorylation, indicating that ATM activation during prolonged replication stress depends on DNA-PK. Depletion of DNA-PK abrogated checkpoint kinase (Chk)2 activation and partially reduced Chk1 activation. Chk2 depletion blocked HU-induced centrosome amplification, indicating a function of Chk2 in centrosome amplification. We further found that Chk2 was phosphorylated at Thr68 on the mother centriole at late G2 and mitosis when unstressed and on all amplified centrioles induced by HU. In summary, we have elucidated that DNA-PK/Chk2 signaling induces centrosome amplification upon long-term HU treatment, therefore increasing our insight into tumor recurrence after initial chemotherapy.


Assuntos
Centrossomo/metabolismo , Quinase do Ponto de Checagem 2/metabolismo , Replicação do DNA , Proteína Quinase Ativada por DNA/metabolismo , Animais , Linhagem Celular , Quinase do Ponto de Checagem 2/genética , Replicação do DNA/efeitos dos fármacos , Proteína Quinase Ativada por DNA/genética , Ativação Enzimática , Deleção de Genes , Humanos , Hidroxiureia/farmacologia , Camundongos , Transporte Proteico , Estresse Fisiológico
15.
BMC Complement Altern Med ; 14: 68, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24555771

RESUMO

BACKGROUND: Zyflamend, a mixture containing extracts of ten herbs, has shown promise in a variety of preclinical cancer models, including prostate cancer. The current experiments were designed to investigate the effects of Zyflamend on the expression of class I and II histone deacetylases, a family of enzymes known to be over expressed in a variety of cancers. METHODS: CWR22Rv1 cells, a castrate-resistant prostate cancer cell line, were treated with Zyflamend and the expression of class I and II histone deacetylases, along with their downstream target the tumor suppressor gene p21, was investigated. Involvement of p21 was confirmed with siRNA knockdown and over expression experiments. RESULTS: Zyflamend down-regulated the expression of all class I and II histone deacetylases where Chinese goldthread and baikal skullcap (two of its components) appear to be primarily responsible for these results. In addition, Zyflamend up regulated the histone acetyl transferase complex CBP/p300, potentially contributing to the increase in histone 3 acetylation. Expression of the tumor suppressor gene p21, a known downstream target of histone deacetylases and CBP/p300, was increased by Zyflamend treatment and the effect on p21 was, in part, mediated through Erk1/2. Knockdown of p21 with siRNA technology attenuated Zyflamend-induced growth inhibition. Over expression of p21 inhibited cell growth and concomitant treatment with Zyflamend enhanced this effect. CONCLUSIONS: Our results suggest that the extracts of this polyherbal combination increase histone 3 acetylation, inhibit the expression of class I and class II histone deacetylases, increase the activation of CBP/p300 and inhibit cell proliferation, in part, by up regulating p21 expression.


Assuntos
Coptis , Histona Desacetilases/metabolismo , Fitoterapia , Extratos Vegetais/farmacologia , Neoplasias da Próstata/metabolismo , Scutellaria , Proteínas Supressoras de Tumor/metabolismo , Acetilação , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo , Histonas/metabolismo , Humanos , Masculino , Extratos Vegetais/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , RNA Interferente Pequeno/metabolismo , Ativação Transcricional , Proteínas Supressoras de Tumor/efeitos dos fármacos , Regulação para Cima , Fatores de Transcrição de p300-CBP/metabolismo
16.
Asian Pac J Cancer Prev ; 14(2): 987-91, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23621273

RESUMO

AIM: To study anti-tumor effects of exosomes from class II transactivator (CIITA) gene transfected CT26 cells. METHODS: In this study, we established an MHC class II molecule-expressing murine colon cancer cell line (CT26-CIITA) by transduction of the CIITA gene. Immune effects in vitro and tumor protective results in vivo were tested and monitored. RESULTS: Exosomes from CT26-CIITA cells were found to contain a high level of MHC class II protein. When loaded on dendritic cells (DCs), exosomes from CT26-CIITA cells significantly increased expression of MHC class II molecules, CD86 and CD80, as compared to exosomes from CT26 cells. In vitro assays using co-culture of immunized splenocytes and exosome-loaded DCs demonstrated that CIITA- Exo enhanced splenocyte proliferation and IFN-γ production of CD4+T cells, while inhibiting IL-10 secretion. In addition, compared to exosomes from CT26 cells, CT26-CIITA-derived exosomes induced higher TNF-α and IL-12 mRNA levels. A mouse tumour preventive model showed that CT26-CIITA derived exosomes significantly inhibited tumour growth in a dose-dependent manner and significantly prolonged the survival time of tumour- bearing mice. CONCLUSION: Our findings indicate that CT26-CIITA-released exosomes are more efficient to induce anti-tumour immune responses, suggesting a potential role of MHC class II-containing tumour exosomes as cancer vaccine candidates.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Neoplasias do Colo/imunologia , Exossomos/imunologia , Proteínas Nucleares/genética , Transativadores/genética , Animais , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Vacinas Anticâncer , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Colo/metabolismo , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Exossomos/metabolismo , Interferon gama/sangue , Interferon gama/metabolismo , Interleucina-10/sangue , Interleucina-10/metabolismo , Interleucina-12/sangue , Interleucina-12/genética , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro/biossíntese , Baço/citologia , Baço/metabolismo , Transfecção , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/genética
17.
Br J Radiol ; 85(1019): 1499-506, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23091290

RESUMO

OBJECTIVE: We compared and evaluated the differences between two models for treating bilateral breast cancer (BBC): (i) dose-volume-based intensity-modulated radiation treatment (DV plan), and (ii) dose-volume-based intensity-modulated radiotherapy with generalised equivalent uniform dose-based optimisation (DV-gEUD plan). METHODS: The quality and performance of the DV plan and DV-gEUD plan using the Pinnacle(3) system (Philips, Fitchburg, WI) were evaluated and compared in 10 patients with stage T2-T4 BBC. The plans were delivered on a Varian 21EX linear accelerator (Varian Medical Systems, Milpitas, CA) equipped with a Millennium 120 leaf multileaf collimator (Varian Medical Systems). The parameters analysed included the conformity index, homogeneity index, tumour control probability of the planning target volume (PTV), the volumes V(20 Gy) and V(30 Gy) of the organs at risk (OAR, including the heart and lungs), mean dose and the normal tissue complication probability. RESULTS: Both plans met the requirements for the coverage of PTV with similar conformity and homogeneity indices. However, the DV-gEUD plan had the advantage of dose sparing for OAR: the mean doses of the heart and lungs, lung V(20) (Gy), and heart V(30) (Gy) in the DV-gEUD plan were lower than those in the DV plan (p<0.05). CONCLUSIONS: A better result can be obtained by starting with a DV-generated plan and then improving it by adding gEUD-based improvements to reduce the number of iterations and to improve the optimum dose distribution. Advances to knowledge The DV-gEUD plan provided superior dosimetric results for treating BBC in terms of PTV coverage and OAR sparing than the DV plan, without sacrificing the homogeneity of dose distribution in the PTV.


Assuntos
Neoplasias da Mama/radioterapia , Dosagem Radioterapêutica/normas , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Radioterapia Conformacional/normas
18.
Nutr Cancer ; 64(5): 749-60, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22663543

RESUMO

Prostate cancer (PrC) is the second deadliest cancer of males in the United States Hormone deprivation therapy (HDT), a common therapy for advanced forms of the disease, results in tumor regression; unfortunately, tumors inevitably become castrate-resistant. Diet is not an appropriate primary therapy for refractory forms of the disease; however, diet may be effective as an adjuvant to HDT, potentially extending the latency period and delaying relapse and/or inhibiting refractory growth. Zyflamend® is a combination of extracts from multiple herbs, each with reported anticancer properties. Zyflamend can inhibit growth of various PrC cell lines, but no studies have investigated its potential use in vivo using a model of castrate-resistant PrC. In this study, oral doses of Zyflamend at human equivalent doses inhibited androgen-dependent and castrate-resistant tumor growth in a mouse model that mimics advanced stages of the disease, and reduced the expression of a number of biomarkers linked to PrC progression including pAKT, prostate specific antigen, histone deacetylases, and androgen receptor. In summary, this is the first article to report that Zyflamend, when provided at human equivalent doses, can potentiate the effects of hormone deprivation on tumor regression and growth inhibition of androgen-dependent and castrate-resistant PrC tumors in vivo.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Suplementos Nutricionais , Extratos Vegetais/uso terapêutico , Neoplasias da Próstata/dietoterapia , Animais , Castração , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Humanos , Masculino , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Distribuição Aleatória , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Testosterona/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Cell Death Dis ; 3: e251, 2012 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-22237208

RESUMO

Galectin-1 is a lectin recognized by galactoside-containing glycoproteins, and is involved in cancer progression and metastasis. The role of galectin-1 in radiosensitivity has not previously been investigated. Therefore, this study tests whether galectin-1 is involved in the radiosensitivity mediated by the H-Ras signaling pathway using cervical carcinoma cell lines. A knockdown of galectin-1 expression in HeLa cells decreased clonogenic survival following irradiation. The clonogenic survival increased in both HeLa and C33A cells with galectin-1 overexpression. The overexpression or knockdown of galectin-1 did not alter radiosensitivity, whereas H-Ras was silenced in both cell lines. Whereas K-Ras was knocked down, galectin-1 restored the radiosensitivity in HeLa cells and C33A cells. The knockdown of galectin-1 increased the high-dose radiation-induced cell death of HeLa cells transfected by constitutively active H-Ras. The knockdown of galectin-1 inhibited the radiation-induced phosphorylation of Raf-1 and ERK in HeLa cells. Overexpression of galectin-1 enhanced the phosphorylation of Raf-1 and ERK in C33A cells following irradiation. Galectin-1 decreased the DNA damage detected using comet assay and γ-H2AX in both cells following irradiation. These findings suggest that galectin-1 mediates radioresistance through the H-Ras-dependent pathway involved in DNA damage repair.


Assuntos
Reparo do DNA/efeitos da radiação , Raios gama , Tolerância a Radiação/genética , Ensaio Cometa , DNA/genética , Galectina 1/genética , Galectina 1/metabolismo , Expressão Gênica , Técnicas de Silenciamento de Genes , Inativação Gênica , Genes Reporter , Células HeLa , Histonas/genética , Histonas/metabolismo , Humanos , Fosforilação , Proteínas Proto-Oncogênicas c-raf/genética , Proteínas Proto-Oncogênicas c-raf/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais/efeitos da radiação , Transfecção , Proteínas ras/genética , Proteínas ras/metabolismo
20.
Oncogene ; 31(9): 1176-80, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21785465

RESUMO

A genome-wide screen for genetic alterations in radiation-induced thymic lymphomas generated from p53+/- and p53-/- mice showed frequent loss of heterozygosity (LOH) on chromosome 6. Fine mapping of these LOH regions revealed three non-overlapping regions, one of which was refined to a 0.2 Mb interval that contained only the gene encoding homeobox-interacting protein kinase 2 (Hipk2). More than 30% of radiation-induced tumors from both p53+/- and p53-/- mice showed heterozygous loss of one Hipk2 allele. Mice carrying a single inactive allele of Hipk2 in the germline were susceptible to induction of tumors by γ-radiation, but most tumors retained and expressed the wild-type allele, suggesting that Hipk2 is a haploinsufficient tumor suppressor gene for mouse lymphoma development. Heterozygous loss of both Hipk2 and p53 confers strong sensitization to radiation-induced lymphoma. We conclude that Hipk2 is a haploinsufficient lymphoma suppressor gene.


Assuntos
Proteínas de Transporte/metabolismo , Raios gama/efeitos adversos , Linfoma/metabolismo , Neoplasias Induzidas por Radiação/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Neoplasias do Timo/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Proteínas de Transporte/genética , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/efeitos da radiação , Cromossomos de Mamíferos , Regulação Neoplásica da Expressão Gênica , Perda de Heterozigosidade , Linfoma/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias Induzidas por Radiação/genética , Ligação Proteica , Proteínas Serina-Treonina Quinases/genética , Neoplasias do Timo/genética , Proteína Supressora de Tumor p53/genética
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