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1.
Indian J Exp Biol ; 53(4): 216-21, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26011982

RESUMO

In this study, we investigated few dietary cucurbits for anticancer activity by monitoring cytotoxic (MTT and LDH assays), apoptotic (caspase-3 and annexin-V assays), and also their anti-inflammatory effects by IL-8 cytokine assay. Aqua-alcoholic (50:50) whole extracts of cucurbits [Lagenaria siceraria (Ls), Luffa cylindrica (Lc) and Cucurbita pepo (Cp)] were evaluated in colon cancer cells (HT-29 and HCT-15) and were compared with isolated biomolecule, cucurbitacin-B (Cbit-B). MTT and LDH assays revealed that the cucurbit extracts and Cbit-B, in a concentration dependent manner, decreased the viability of HT-29 and HCT-15 cells substantially. The viability of lymphocytes was, however, only marginally decreased, yielding a potential advantage over the tumor cells. Caspase-3 assay revealed maximum apoptosis with Ls while annexin V assay demonstrated maximum efficacy of Lc in this context. These cucurbits have also shown decreased secretion of IL-8, thereby revealing their anti-inflammatory capability. The results have demonstrated the therapeutic potential of dietary cucurbits in inhibiting cancer and inflammatory cytokine.


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Cucurbita , Dieta , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos
2.
Br J Cancer ; 104(4): 629-34, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21285984

RESUMO

BACKGROUND: The molecular chaperone heat shock protein-90 (Hsp90) is a promising cancer drug target, but current Hsp90-based therapy has so far shown limited activity in the clinic. METHODS: We tested the efficacy of a novel mitochondrial-targeted, small-molecule Hsp90 inhibitor, Gamitrinib (GA mitochondrial matrix inhibitor), in the Transgenic Adenocarcinoma of the Mouse Prostate (TRAMP) model. The TRAMP mice receiving 3-week or 5-week systemic treatment with Gamitrinib were evaluated for localised or metastatic prostate cancer, prostatic intraepithelial neoplasia (PIN) or localised inflammation using magnetic resonance imaging, histology and immunohistochemistry. Treatment safety was assessed histologically in organs collected at the end of treatment. The effect of Gamitrinib on mitochondrial dysfunction was studied in RM1 cells isolated from TRAMP tumours. RESULTS: Systemic administration of Gamitrinib to TRAMP mice inhibited the formation of localised prostate tumours of neuroendocrine or adenocarcinoma origin, as well as metastatic prostate cancer to abdominal lymph nodes and liver. The Gamitrinib treatment had no effect on PIN or prostatic inflammation, and caused no significant animal weight loss or organ toxicity. Mechanistically, Gamitrinib triggered acute mitochondrial dysfunction in RM1 cells, with loss of organelle inner membrane potential and release of cytochrome-c in the cytosol. CONCLUSIONS: The Gamitrinib has pre-clinical activity and favourable tolerability in a genetic model of localised and metastatic prostate cancer in immunocompetent mice. Selective targeting of mitochondrial Hsp90 could provide novel molecular therapy for patients with advanced prostate cancer.


Assuntos
Adenocarcinoma/prevenção & controle , Antineoplásicos/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Guanidinas/uso terapêutico , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Lactamas Macrocíclicas/uso terapêutico , Neoplasias da Próstata/prevenção & controle , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Antineoplásicos/farmacologia , Células Cultivadas , Modelos Animais de Doenças , Progressão da Doença , Avaliação Pré-Clínica de Medicamentos , Feminino , Predisposição Genética para Doença , Guanidinas/farmacologia , Proteínas de Choque Térmico HSP90/metabolismo , Lactamas Macrocíclicas/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Terapia de Alvo Molecular/métodos , Metástase Neoplásica , Neoplasia Prostática Intraepitelial/genética , Neoplasia Prostática Intraepitelial/patologia , Neoplasia Prostática Intraepitelial/prevenção & controle , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia
3.
Andrologia ; 43(1): 75-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21219388

RESUMO

In this case report we present a family with infertile, azoospermic but otherwise apparently healthy males with history of recurrent spontaneous abortions (RSA) in females. Karyotype of the infertile man revealed a reciprocal balanced translocation t(8; 13) with breakpoints at 8q22 and 13p11.2. The reported reciprocal balanced translocation is associated with azoospermia. The same translocation is probably the cause of RSA in females of the family.


Assuntos
Aborto Espontâneo/genética , Infertilidade Masculina/genética , Translocação Genética/genética , Aborto Espontâneo/epidemiologia , Aberrações Cromossômicas , Cromossomos Humanos Par 13/genética , Cromossomos Humanos Par 8/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Recidiva
4.
Pharm Dev Technol ; 16(1): 57-64, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20028210

RESUMO

The objective of the study was to develop a mathematical model for predicting the disintegration time of fast disintegrating tablets (FDTs) by estimating the powder characteristics of powder blend prior to compression. A combination of chitosan-alginate complex and glycine in the ratio of 50:50 was used for preparing FDTs. The developed mathematical model allowed water sorption time (WST), effective pore radius (R(eff.p)) and swelling Index (SI) of powder mixture as well as tablet crushing strength to be successfully correlated with disintegration time (DT) of FDTs. The predicted model showed that disintegration time of FDTs to be directly correlated with powder characteristics and inversely correlated with tablet crushing strength. Furthermore, a correlation of 0.97 was obtained when DT of FDTs was compared with SI/(WST * R(eff.p)). This correlation was not affected by inclusion of water soluble (ondansetron hydrochloride or metaclopramide hydrochloride) or water insoluble (domperidone) drugs in the powder blend or FDTs. These observations indicated the versatility of the mathematical model in predicting the disintegration time of FDTs by evaluating the selected characteristics of the powder blends without actually preparing the FDTs.


Assuntos
Modelos Químicos , Pós/química , Comprimidos/química , Adsorção , Química Farmacêutica , Quitosana/química , Força Compressiva , Domperidona/administração & dosagem , Domperidona/química , Estabilidade de Medicamentos , Excipientes/química , Glicina/química , Metoclopramida/administração & dosagem , Metoclopramida/química , Ondansetron/administração & dosagem , Ondansetron/química , Solubilidade , Fatores de Tempo , Água
5.
Indian J Otolaryngol Head Neck Surg ; 71(Suppl 1): 679-683, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31742041

RESUMO

Teachers are heavy voice users, and they suffer from voice problems more frequently than other occupational voice users. Various studies have demonstrated that teachers speak longer than other professionals and that school teachers in particular, are at risk for voice problems such as vocal fatigue and vocal nodules. The present study is undertaken to study the prevalence of voice disorders in the teachers in different schools at any time and accesses the relationship of different working conditions like class room size, background noise, number of hours taught every day and role of chalk allergy in development of these voice disorders. The study was carried out on 133 school teachers with self reporting of voice problems through detailed questionnaire. A significant number of teachers, more so females had voice problems attributed to various factors. Voice amplification and reduction of background noise along with measures to control allergy are suggested.

6.
Indian J Otolaryngol Head Neck Surg ; 71(Suppl 2): 1320-1326, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31750172

RESUMO

Tympanoplasty which is the repair of the tympanic membrane using temporalis fascia, has been done worldwide and has stood the test of time. However in cases of reperforation or large/subtotal perforations, we are often left in need of some sturdy material for grafting. To compare the graft uptake and hearing improvement in patients undergoing type I tympanoplasty using temporalis fascia alone and temporalis fascia along with conchal cartilage. The current research is a prospective study of 60 patients with chronic suppurative otitis media (Tubo tympanic type), undergoing type I tympanoplasty, using temporalis fascia alone and temporalis fascia along with conchal cartilage. The graft uptake and hearing improvement was much better using temporalis fascia along with conchal cartilage graft as compared to cartilage alone. The use of temporalis fascia along with conchal cartilage graft is beneficial for patients with chronic suppurative otitis media (tubotympanic type) undergoing type I tympanoplasty than using temporalis fascia alone.

7.
Oncogene ; 26(19): 2678-84, 2007 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-17072337

RESUMO

Survivin is a dual regulator of cell proliferation and cell viability overexpressed in most human tumors. Although strategies to lower survivin levels have been pursued for rational cancer therapy, the molecular circuitries controlling survivin expression in tumors have not been completely elucidated. Here, we show that stimulation with insulin-like growth factor-1 (IGF-1) results in increased survivin expression in prostate cancer cells. This response is independent of de novo gene transcription, changes in mRNA expression or modifications of survivin protein stability. Instead, IGF-1 induced persistence and translation of a pool of survivin mRNA, in a reaction abolished by the mTOR (mammalian target of rapamycin) inhibitor, rapamycin. Forced expression of the mTOR target p70S6K1 reproduced the increase in survivin expression in prostate cancer cells, whereas acute ablation of endogenous p70S6K1 by small interfering RNA downregulated survivin levels. Rapamycin, alone or in combination with suboptimal concentrations of taxol reduced survivin protein levels, and decreased viability of prostate cancer cells. Therefore, IGF-1/mTOR signaling elevates survivin in prostate cancer cells via rapid changes in mRNA translation. Antagonists of this pathway may be beneficial to lower an antiapoptotic threshold maintained by survivin in prostate cancer.


Assuntos
Regulação Neoplásica da Expressão Gênica , Fator de Crescimento Insulin-Like I/farmacologia , Proteínas Associadas aos Microtúbulos/genética , Proteínas de Neoplasias/genética , Neoplasias da Próstata/metabolismo , Proteínas Quinases/metabolismo , Transdução de Sinais , Animais , Apoptose , Ciclo Celular , Proliferação de Células , Regulação para Baixo , Células HeLa , Humanos , Proteínas Inibidoras de Apoptose , Masculino , Camundongos , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/antagonistas & inibidores , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Regiões Promotoras Genéticas , Neoplasias da Próstata/genética , Proteínas Quinases/genética , Estabilidade de RNA , RNA Interferente Pequeno/farmacologia , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/fisiologia , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Sirolimo , Survivina , Serina-Treonina Quinases TOR , Transcrição Gênica , Células Tumorais Cultivadas/efeitos dos fármacos
8.
BJOG ; 115(5): 633-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18333945

RESUMO

OBJECTIVES: Inflammation plays a major role in pathogenesis of cervical cancer. We planned to study whether polymorphisms in inflammation-related genes, IL-1RN (VNTR) and IL-1beta (-511C/T), are associated with risk of cervical cancer. DESIGN: Case-control study. SETTING: Uttar Pradesh state in India. SAMPLE: One hundred and fifty, histopathologically confirmed cases with cervical cancer and 162 age-, ethnicity-matched, cervical cytology negative, healthy controls were recruited to this study. METHODS: Genotyping of IL-1RN (VNTR) and IL-1beta (-511C/T) polymorphisms was performed using polymerase chain reaction (PCR)/PCR-restriction fragment length polymorphism. Power of study was 80% with type 1 error of 0.05. Haplotypes frequencies were obtained by computer package 'Arlequin'. MAIN OUTCOME MEASURES: Haplotype IL-1RN*2/IL-1beta*T is associated with higher risk and of cervical cancer. RESULTS: IL-1RN genotypes 1/2 and 2/2 were associated with significantly elevated risk of cervical cancer (OR = 3.3; P= 4.9 x 10(-6) and OR = 2.9, P= 0.02). Similarly, TT genotype of IL-1betapolymorphism was significantly higher in cases compared with controls (57.7 versus 38.3%; OR = 2.8; P = 0.012). 2/2 genotype of IL-1RN (OR = 4.8, P = 0.0006) and TT genotype of IL-1beta(OR = 5.2; P = 0.02) were associated with the higher stages (III) of cervical cancer. Haplotypes 1T (IL-1RN*1/IL-1beta*T) and 2T (IL-1RN*2/IL-1beta*T) were also significantly associated with higher susceptibility to cervical cancer and its progression. Logistic regression analysis suggests IL-1RN allele 2 and IL-1beta-511T were independently associated with increased risk for cervical cancer. CONCLUSION: IL-1RN*2 and IL-1beta -511*T in various combinations of genotypes and haplotypes are associated with higher susceptibility for cervical cancer.


Assuntos
Proteína Antagonista do Receptor de Interleucina 1/genética , Interleucina-1/genética , Interleucina-1beta/genética , Polimorfismo Genético/genética , Neoplasias do Colo do Útero/genética , Estudos de Casos e Controles , DNA/genética , Feminino , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Pessoa de Meia-Idade , Fatores de Risco
9.
Neurogastroenterol Motil ; 30(9): e13371, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29781137

RESUMO

BACKGROUND: Primary chronic intestinal pseudo-obstruction (CIPO) is a rare, potentially life-threatening disorder characterized by severely impaired gastrointestinal motility. The objective of this study was to examine the contribution of ACTG2, LMOD1, MYH11, and MYLK mutations in an Australasian cohort of patients with a diagnosis of primary CIPO associated with visceral myopathy. METHODS: Pediatric and adult patients with primary CIPO and suspected visceral myopathy were recruited from across Australia and New Zealand. Sanger sequencing of the genes encoding enteric gamma-actin (ACTG2) and smooth muscle leiomodin (LMOD1) was performed on DNA from patients, and their relatives, where available. MYH11 and MYLK were screened by next-generation sequencing. KEY RESULTS: We identified heterozygous missense variants in ACTG2 in 7 of 17 families (~41%) diagnosed with CIPO and its associated conditions. We also identified a previously unpublished missense mutation (c.443C>T, p.Arg148Leu) in one family. One case presented with megacystis-microcolon-intestinal hypoperistalsis syndrome in utero with subsequent termination of pregnancy at 28 weeks' gestation. All of the substitutions identified occurred at arginine residues. No likely pathogenic variants in LMOD1, MYH11, or MYLK were identified within our cohort. CONCLUSIONS AND INFERENCES: ACTG2 mutations represent a significant underlying cause of primary CIPO with visceral myopathy and associated phenotypes in Australasian patients. Thus, ACTG2 sequencing should be considered in cases presenting with hypoperistalsis phenotypes with suspected visceral myopathy. It is likely that variants in other genes encoding enteric smooth muscle contractile proteins will contribute further to the genetic heterogeneity of hypoperistalsis phenotypes.


Assuntos
Actinas/genética , Predisposição Genética para Doença/genética , Pseudo-Obstrução Intestinal/genética , Adolescente , Adulto , Australásia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Adulto Jovem
10.
J Med Food ; 9(2): 154-60, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16822199

RESUMO

Rhodiola imbricata, an Indian medicinal plant, was investigated for protection against whole-body lethal gamma irradiation (10 Gy)-induced mortality in Swiss albino strain "A" mice. The maximum tolerance dose values for aqueous (RD-I) and aqua-alcoholic (RD-II) extracts were 1,100 and 1,300 mg/kg of body weight, respectively. Pre-irradiation administration of RD-I produced >90% survival, while RD-II produced >83% survival beyond the 30-day observation period. The optimal radioprotective dose for RD-I as well as RD-II was 350 mg/kg of body weight; the aqua-alcoholic extract, however, had an advantage over the aqueous extract at lower as well as at higher doses. The optimal time interval between administration of extract and irradiation was 30 minutes for both RD-I and RD-II. The number of colony-forming units per spleen in irradiated mice was 1.91 +/- 0.15, while in mice given RD-I or RD-II, 30 minutes before irradiation (10 Gy), it increased to 17.3 +/- 0.67 and 15.6 +/- 0.61, respectively. These findings have important implications in the development of a suitable radioprotector of herbal origin.


Assuntos
Protetores contra Radiação/administração & dosagem , Rhodiola/química , Irradiação Corporal Total/efeitos adversos , Animais , Etanol , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos da radiação , Masculino , Dose Máxima Tolerável , Camundongos , Baço/citologia , Baço/efeitos da radiação , Células-Tronco , Fatores de Tempo , Água
11.
Oncogene ; 35(9): 1111-21, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-25982283

RESUMO

IMP3 (insulin-like growth factor-2 mRNA binding protein 3) is an oncofetal protein whose expression is prognostic for poor outcome in several cancers. Although IMP3 is expressed preferentially in triple-negative breast cancer (TNBC), its function is poorly understood. We observed that IMP3 expression is significantly higher in tumor initiating than in non-tumor initiating breast cancer cells and we demonstrate that IMP3 contributes to self-renewal and tumor initiation, properties associated with cancer stem cells (CSCs). The mechanism by which IMP3 contributes to this phenotype involves its ability to induce the stem cell factor SOX2. IMP3 does not interact with SOX2 mRNA significantly or regulate SOX2 expression directly. We discovered that IMP3 binds avidly to SNAI2 (SLUG) mRNA and regulates its expression by binding to the 5' UTR. This finding is significant because SLUG has been implicated in breast CSCs and TNBC. Moreover, we show that SOX2 is a transcriptional target of SLUG. These data establish a novel mechanism of breast tumor initiation involving IMP3 and they provide a rationale for its association with aggressive disease and poor outcome.


Assuntos
Biomarcadores Tumorais/biossíntese , Proteínas de Ligação a RNA/biossíntese , Fatores de Transcrição/biossíntese , Neoplasias de Mama Triplo Negativas/genética , Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Células-Tronco Neoplásicas , Prognóstico , RNA Mensageiro/biossíntese , Proteínas de Ligação a RNA/genética , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética , Neoplasias de Mama Triplo Negativas/patologia
12.
J Pharm Pharmacol ; 57(8): 1065-72, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16102264

RESUMO

Alcoholic extract of Hippophae rhamnoides, RH-3, reported to render >80% survival against lethal whole body Co-60-gamma irradiation (10 Gy) in mice, was investigated for its immunostimulatory effects. In comparison with un-irradiated control, whole body irradiation did not reduce peritoneal macrophage counts at 24 h post-irradiation. RH-3 treatment (30 mg kg(-1) body weight) alone or 30 min before whole-body irradiation enhanced viable counts of macrophages significantly (P< or =0.05) compared with both un-irradiated control and irradiated groups. Whole-body irradiation reduced the number of viable splenocytes significantly (P<0.05) compared with un-irradiated control at 24 h post-irradiation. RH-3 treatment alone or before whole-body irradiation appreciably countered radiation-induced decrease in splenocyte count. 3H-thymidine uptake method revealed that whole-body irradiation reduced splenocyte proliferation significantly (159 +/- 45 counts min(-1)/10(6) cells; P< or =0.05) in comparison with control (607 +/- 142 counts min(-1)) at 24 h after irradiation but RH3 treatment before irradiation reduced the steep decrease and maintained it as 444+/-153 counts min(-1). After whole-body irradiation, the ratio of spleen weight/mouse weight decreased to 1.5 +/- 04 compared with 2.9 +/- 0.32 in un-irradiated control at 24 h post-irradiation. Similarly, total protein content in splenocytes also decreased to 48 +/- 6 microg/10(6) cells in comparison with 368 +/- 16 microg/10(6) cells of un-irradiated control. RH-3 treatment before irradiation countered radiation-induced decrease in both spleen weight/mouse weight ratio (4.0 +/- 0.35) and total protein content (360 +/- 13 mug/10(6) splenocytes). In the supernatant of peritoneal macrophage cultures exposed to 2 Gy Co-60-gamma radiation ex-vivo, the total nitrite content was enhanced significantly (P<0.05) to 5.72 +/- 0.09 microM in comparison with un-irradiated control (1.64 +/- 0.09 microM). RH-3 treatment (30 microg mL(-1)) before irradiation reduced total nitrite significantly (0.93 +/- 0.3; P< or =0.05) in comparison with irradiated control group. At 24 h after whole body irradiation, the CD4+/CD8+ ratio reduced to 1.5 in comparison with un-irradiated control (1.9) but RH-3 treatment before irradiation restored the ratio to 2.1. These findings explicitly reveal the immunostimulatory activity of RH-3, which may play an important role in the manifestation of its radioprotective efficacy.


Assuntos
Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/fisiologia , Macrófagos Peritoneais/efeitos dos fármacos , Extratos Vegetais/farmacologia , Protetores contra Radiação/farmacologia , Baço/efeitos dos fármacos , Animais , Antígenos CD4/análise , Antígenos CD8/análise , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Raios gama , Hippophae , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Nitritos/metabolismo , Extratos Vegetais/administração & dosagem , Proteínas/metabolismo , Protetores contra Radiação/administração & dosagem , Baço/citologia , Baço/metabolismo , Baço/efeitos da radiação , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/efeitos da radiação
13.
Cell Prolif ; 35(3): 131-42, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12027949

RESUMO

Focal adhesion kinase (FAK) was heavily phosphorylated as a function of differentiation of C2C12 mouse skeletal muscle cells. Insulin caused increases in FAK phosphorylation before stabilization in proliferated cells, while in differentiated cells there was a consistent transient inhibition of FAK phosphorylation before stimulation. The expression level of FAK was unaltered. Specific inhibition of insulin receptor tyrosine kinase activity abolished the insulin-mediated dephosphorylation of FAK. The data strongly indicate that FAK tyrosine phosphorylation, necessary for skeletal muscle differentiation, is modulated by insulin. Thus, for the first time, we report the differential regulation of FAK tyrosine phosphorylation by insulin during skeletal muscle differentiation.


Assuntos
Insulina/farmacologia , Músculo Esquelético/enzimologia , Fosfotirosina/metabolismo , Proteínas Tirosina Quinases/metabolismo , Animais , Diferenciação Celular , Linhagem Celular , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Cinética , Camundongos , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Fosforilação
14.
Cancer Lett ; 43(1-2): 21-7, 1988 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-3203326

RESUMO

The comparative radiosensitizing effects of camphor and metronidazole on murine transplantable mammary adenocarcinoma are reported. Male C3H/Jax mice bearing transplanted mammary tumours were treated with camphor (0.5 microM/body wt) or metronidazole (0.5 microM/g body wt) 45 min before subjecting to local X-irradiation at the dose levels of 30, 80, 100 or 120 Gy. Sequential in situ measurement of the tumour volumes during the follow-up period of 45 days revealed that the maximum enhancement ratios of tumour growth delay for camphor and metronidazole were 4.8 and 2.5, respectively. This suggests that camphor can be a potential radiosensitizing agent in cancer radiotherapy.


Assuntos
Adenocarcinoma/patologia , Cânfora/farmacologia , Neoplasias Mamárias Experimentais/patologia , Radiossensibilizantes , Animais , Masculino , Metronidazol/farmacologia , Camundongos , Camundongos Endogâmicos C3H , Transplante de Neoplasias
15.
Nucl Med Biol ; 27(4): 419-26, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10938479

RESUMO

A quick and reproducible method for radiolabeling of Photosan-3(R), a photosensitizer used worldwide for photodynamic therapy (PDT) of cancer, with radioisotope of technetium ((99m)Tc) was developed. The radiotracer was evaluated for radiochemical purity, stability, and tissue distribution in a murine tumor model. The (99m)Tc-Photosan-3, which was prepared by using (99m)Tc-pertechnetate in place of reduced (99m)Tc, demonstrated better labeling efficiency (>90%) and reproducibility. The procedure also minimized radiation exposure to the radiochemist because handling time was considerably reduced. Due to the commercial availability of Photosan-3, the risk of batch-to-batch variation in the in situ synthesis of hematoporphyrin derivative, which is a complex mixture of at least five compounds, was also significantly reduced. The biodistribution studies and tumor scintigraphy confirmed that (99m)Tc-labeled Photosan-3 was preferentially taken up by the neoplastic tissue similar to the parent compound. In addition to its applications in tumor imaging, (99m)Tc-Photosan-3 could also be used for estimating tumor uptake of Photosan-3 as may be required for individualization of clinical protocols of PDT.


Assuntos
Neoplasias Experimentais/diagnóstico por imagem , Fármacos Fotossensibilizantes , Compostos Radiofarmacêuticos , Tecnécio , Animais , Arbovírus , Estabilidade de Medicamentos , Hematoporfirinas , Marcação por Isótopo , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacocinética , Ligação Proteica , Coelhos , Cintilografia , Distribuição Tecidual
16.
Nucl Med Biol ; 27(6): 587-92, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11056374

RESUMO

A quick and reproducible method for radiolabeling of Photosan-3(R), a photosensitizer used worldwide for photodynamic therapy (PDT) of cancer, with radioisotope of technetium ((99m)Tc) was developed. The radiotracer was evaluated for radiochemical purity, stability, and finally tissue distribution in a murine tumor model. The (99m)Tc-Photosan-3 prepared by using (99m)Tc-pertechnetate in place of reduced (99m)Tc demonstrated better labeling efficiency (>90%) and reproducibility. The procedure also minimized the radiation exposure to the radiochemist as handling time was considerably reduced. Due to the commercial availability of Photosan-3, the risk of batch-to-batch variation in the in situ synthesis of hematoporphyrin derivative, which is a complex mixture of at least five compounds, was also significantly reduced. The biodistribution studies and tumor scintigraphy confirmed that (99m)Tc-labeled Photosan-3 was preferentially taken up by the neoplastic tissue in a manner similar to the parent compound. In addition to applications in tumor imaging, (99m)Tc-Photosan-3 could also be used for estimating tumor uptake of Photosan-3 as may be required for individualization of clinical protocols of PDT.


Assuntos
Carcinoma de Ehrlich/diagnóstico por imagem , Hematoporfirinas , Fármacos Fotossensibilizantes , Compostos Radiofarmacêuticos , Tecnécio/química , Animais , Carcinoma de Ehrlich/metabolismo , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Estabilidade de Medicamentos , Hematoporfirinas/química , Hematoporfirinas/farmacocinética , Taxa de Depuração Metabólica , Camundongos , Transplante de Neoplasias , Especificidade de Órgãos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacocinética , Coelhos , Cintilografia , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Pertecnetato Tc 99m de Sódio/química , Tecnécio/análise , Compostos de Estanho/química , Distribuição Tecidual
17.
Physiol Behav ; 73(1-2): 19-23, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11399290

RESUMO

Radiations are known to cause behavioural perturbations like conditioned taste aversion (CTA), performance decrement, learning, etc., even at very low doses. The manifestation of radiation-induced behavioural degradation has not been understood well and requires further studies. Therefore, the effects of low-dose whole-body 60Co gamma-irradiation in male rats were studied in terms of body weight and CTA learning. For CTA, the consumption of saccharin solution was considered as a parameter. To protect against the adverse effects of radiation, Centella asiatica (aqueous extract) was tested and compared with ondansetron, a standard antiemetic drug. A dose of 2 Gy incurred significant body weight loss [t(9)=9.00, P<.05] and induced CTA in rats [t(26)=9.344, P<.01]. Administration of C. asiatica (100 mg/kg bw ip, 2 Gy, -1 h) rendered significant radioprotection against radiation-induced body weight loss and CTA that became evident on the second postirradiation day [t(7)=0.917, P>>.05; t(7)=4.016, P>.05]. Ondansetron (1 mg/kg bw) elicited higher degree of protection against CTA [t(7)=3.641, P>.05] than C. asiatica [t(7)=7.196, P>.05] on the first postirradiation day, but on the second postirradiation day, both were equally effective [t(7)=3.38, P>.05; t(7)=4.01, P>.05]. In case of C. asiatica-treated animals, however, there was a consistently declining CTA from the second to the fifth postirradiation day whereas in ondansetron-treated animals it was inconsistent. Present investigation suggests that C. asiatica could be useful in preventing radiation-induced behavioural changes during clinical radiotherapy.


Assuntos
Aprendizagem da Esquiva/efeitos da radiação , Condicionamento Clássico/efeitos da radiação , Protetores contra Radiação/farmacologia , Paladar/efeitos da radiação , Triterpenos/farmacologia , Animais , Radioisótopos de Cobalto , Relação Dose-Resposta à Radiação , Masculino , Ondansetron/farmacologia , Teleterapia por Radioisótopo , Ratos , Ratos Wistar , Redução de Peso/efeitos da radiação , Irradiação Corporal Total
18.
Biomed Pharmacother ; 58(2): 129-35, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14992795

RESUMO

The aqueous extract of RP-1, which rendered significant protection to whole body irradiated mice, was found to be tumoricidal. The mode of cytotoxic action of RP-1 attributing to its antitumor action was investigated in U 87 cells with special reference to mitochondrial contribution. RP-1 doses above 0.5 microg/ml reduced colonogenic survival (maximum reduction of 62% at 10 microg/ml) and increased the free radical generation, G2/M fraction and apoptotic frequency. Prolonged exposure to RP-1 rendered significant increase in mitochondrial mass. It also reduced mitochondrial membrane potential in a dose and time dependent manner that was restored by verapamil, a Ca+2 channel blocker. Mitochondrial anti-apoptotic proteins Bcl-2 and Hsp-70 levels were also reduced by RP-1 treatment in a dose and time dependent manner. The ability of RP-1 to disrupt mitochondrial structure and function could be responsible for its cytotoxic action.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Podophyllum , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Radicais Livres/metabolismo , Proteínas de Choque Térmico HSP70/biossíntese , Humanos , Potenciais da Membrana , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Rizoma
19.
Mutat Res ; 224(2): 157-60, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2677707

RESUMO

The frequency of sister-chromatid exchanges (SCE) in mouse bone marrow exposed to gamma-irradiation was used to assess the radiomodifying effect of camphor. Hoechst 33258 plus Giemsa was used for SCE analysis. The radiation-induced SCE frequency was significantly low after a single dose of camphor (0.5 microM/g b.w.) administered 30, 45 or 60 min before irradiation; the effect was enhanced with increasing time intervals.


Assuntos
Medula Óssea/efeitos dos fármacos , Cânfora/toxicidade , Radiossensibilizantes/toxicidade , Troca de Cromátide Irmã/efeitos dos fármacos , Animais , Medula Óssea/efeitos da radiação , Camundongos , Camundongos Endogâmicos A , Troca de Cromátide Irmã/efeitos da radiação , Irradiação Corporal Total
20.
J Radiat Res ; 42(3): 285-94, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11840645

RESUMO

We have studied the effects of 2-deoxy-D-Glucose (2-DG) on the recovery of potentially lethal damage (PLDR), repair of chromosomal DNA, cyclobutane pyrimidine dimers (CPDs), reverse mutation and gene-conversion in UVC (254 nm) irradiated yeast. As studied by pulsed-field gel electrophoresis, post-irradiation chromosomal DNA repair kinetics in a phosphate buffer (PB) with 10 mM glucose (G) was biphasic, where the first phase exhibited a decrease and the second phase showed an increase in the band intensities. A post-irradiation treatment in PB + G (10 mM) with 2-DG (10, 20, 50 mM) reduced the decrease in the DNA band intensities in the first phase of DNA repair. As compared to a post-irradiation (125 J/m2) treatment in PB + G (10 mM), a treatment in PB + G (10 mM) + 2-DG (10 mM) showed a decreased PLDR, but increased revertants and gene-convertants.


Assuntos
Reparo do DNA/efeitos dos fármacos , Desoxiglucose/farmacologia , Mutagênese/efeitos dos fármacos , Raios Ultravioleta , Cromossomos/efeitos da radiação , Saccharomyces cerevisiae
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