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1.
Eur J Pharmacol ; 958: 176010, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37634841

RESUMO

In decompensated cirrhosis, the severity of portal hypertension (PHT) is associated with increased hepatic endothelial nitric oxide synthase (eNOS) trafficking inducer (Nostrin), but the mechanism remains unclear. AIM: To investigate: (1) Whether in cirrhosis-PHT models, ± superimposed inflammation to mimic acute-on-chronic liver failure (ACLF) modulates hepatic nitric oxide synthase trafficking inducer (NOSTRIN) expression, nitric oxide (NO) synthesis, and/or endothelial dysfunction (ED); and (2) Whether the "angiotensin II type 1 receptor blocker" candesartan cilexetil (CC) affects this pathway. CD-1 mice received intraperitoneal carbon tetrachloride injections (CCl4 15% v/v in corn oil, 0.5 mL/kg) twice weekly for 12 wk to induce cirrhosis. After 12 wk, mice were randomized to receive 2-wk oral administration of CC (8 mg/kg) ± LPS. At sacrifice, plasma (biochemical indicators, cytokines, and angiotensin II) and liver tissues (histopathology, Sirius-red stains, and molecular studies) were analysed. Moreover, Nostrin gene knockdown was tested in human umbilical vein endothelial cells (HUVECs). When compared to naïve animals, CCl4-treated animals showed markedly elevated hepatic Nostrin expression (P < 0.0001), while hepatic peNOS expression (measure of eNOS activity) was significantly reduced (P < 0.05). LPS challenge further increased Nostrin and reduced peNOS expression (P < 0.05 for both) in cirrhotic animals. Portal pressure and subsequent hepatic vascular resistance were also increased in all cirrhotic animals following LPS challenge. In CCl4 ± LPS-treated animals, CC treatment significantly reduced Nostrin (P < 0.05) and increased hepatic cGMP (P < 0.01). NOSIP, caveolin-1, NFκB, and iNOS protein expression were significantly increased in CCl4-treated animals (P < 0.05 for all). CC treatment non-significantly lowered NOSIP and caveolin-1 expression while iNOS and NFκB expression was significantly reduced in CCl4 + LPS-treated animals (P < 0.05 for both). Furthermore, Nostrin knockdown significantly improved peNOS expression and associated NO synthesis and reduced inflammation in HUVECs. This study is the first to indicate a potential mechanistic role for the Nostrin-eNOS-NO pathway in cirrhosis and ACLF development. Moreover, this pathway provides a potential therapeutic target given the ameliorative response to Candesartan treatment.


Assuntos
Insuficiência Hepática Crônica Agudizada , Hipertensão Portal , Animais , Humanos , Camundongos , Insuficiência Hepática Crônica Agudizada/complicações , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Caveolina 1/metabolismo , Proteínas de Ligação a DNA/metabolismo , Células Endoteliais/metabolismo , Hipertensão Portal/complicações , Hipertensão Portal/tratamento farmacológico , Inflamação/complicações , Lipopolissacarídeos , Cirrose Hepática/complicações , Cirrose Hepática/tratamento farmacológico , NF-kappa B/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Pressão na Veia Porta
2.
Infect Prev Pract ; 5(2): 100279, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37006320

RESUMO

Background: We assess the efficacy of orientation programmes for doctors of proper donning, doffing techniques for personal protective equipment (PPE) and safe practices inside the COVID-19 hospital in reducing the COVID-19 infection rate among doctors. Methods: A total of 767 resident doctors and 197 faculty visits on weekly rotation were recorded over a six month period. Doctors were guided through orientation sessions before their entry into the COVID-19 hospital from 1 August 2020. The infection rate among doctors was used to study the efficacy of the programme. McNemars Chi-square test was used to compare the infection rate in the two groups before and after orientation sessions were commenced. Discussion: A statistically significant reduction in SARS-CoV-2 infection was seen among resident doctors after orientation programmes and infrastructure modification (3% vs 7.4%, P=0.03). Twenty-eight of 32 (87.5%) doctors who tested positive developed asymptomatic to mild infection. The infection rate was 3.65% and 2.1% among residents and faculty respectively. There was no mortality recorded. Conclusion: Orientation programme for healthcare workers for PPE donning and doffing protocols with practical demonstration and trial of PPE usage can significantly reduce COVID-19 infection. Such sessions should be mandatory for all workers on deputation in designated area for Infectious Diseases and in pandemic situations.

3.
Mar Pollut Bull ; 188: 114611, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36731375

RESUMO

In the Gulf of Mannar, Noctiluca scintillans blooms have been observed three times in September 2019, September and October 2020, and October 2021. It was determined and measured how the bloom period affects ichthyo-diversity. Noctiluca cell density varied slightly from year to year, ranging from1.8433 × 103 cells/L to 1.3824 x 106cells/L. In surface and sea bottom waters, high ammonia levels and low dissolved oxygen levels were noted. During the bloom period a significant increase in chlorophyll concentration was found. The amount of chlorophyll in GOM was extremely high, according to remote sensing photos made using MODIS-Aqua 4 km data. Acute hypoxia caused the death of wild fish near coral reefs and also in fish reared in sea cages. The decay of the bloom resulted in significant ammonia production, a dramatic drop in the amount of dissolved oxygen in the water, and ultimately stress, shock, and mass mortality of fishes.


Assuntos
Diatomáceas , Dinoflagellida , Animais , Proliferação Nociva de Algas , Fitoplâncton , Amônia , Monitoramento Ambiental/métodos , Estações do Ano , Clorofila , Peixes , Índia , Oxigênio
4.
Biomed Mater ; 18(1)2022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-36270604

RESUMO

The incidence of highly aggressive pancreatic cancer is increasing across the globe and is projected to increase to 18.6% by 2050. The mortality rate for this form of cancer is very high and the 5 y relative survival rate is only about 9%-10%. The 3D pancreatic cancer microenvironment exerts a major influence on the poor survival rate. A key factor is the prevention of the penetration of the chemotherapeutic drugs in the three-dimensional (3D) microenvironment leading to the development of chemoresistance which is a major contributor to the survival rates. Hence,in vitrostudies using 3D cultures represent a better approach to understand the effect of therapeutic formulations on the cancer cells when compared to conventional 2D cultures. In the present study, we have explored three different conditions for the development of a 3D pancreatic tumour spheroid model from MiaPaCa-2 and PanC1 cells cultured for 10 days using Matrigel matrix. This optimized spheroid model was employed to evaluate a multi-functional nanotheranostic system fabricated using chitosan nanoparticles co-encapsulated with the chemotherapeutic agent gemcitabine and gold-capped iron oxide nanoparticles for multimodal imaging. The effect of the single and multiple-dose regimens of the theranostic system on the viability of 3D spheroids formed from the two pancreatic cancer cell lines was studied. It was observed that the 3D tumour spheroids cultured for 10 days exhibited resistance towards free gemcitabine drug, unlike the 2D culture. The administration of the multifunctional nanotheranostic system on alternate days effectively reduced the cancer cell viability after five doses to about 20% when compared with other groups. The repeated doses of the nanotheranostic system were found to be more effective than the single dose. Cell line-based differences in internalization of the carrier was also reflected in their response to the nanocarrier with PanC1 showing better sensitivity to the treatment.In vivostudies revealed that the combination of gemcitabine and magnetic field induced hypothermia produced superior regression in cancer when compared with the chemotherapeutic agent alone by a combination of activating the pro-apoptotic pathway and heat-induced necrosis. Our results reveal that this multi-functional system holds promise to overcome the current challenges to treat pancreatic cancers.


Assuntos
Antineoplásicos , Neoplasias Pancreáticas , Humanos , Nanomedicina Teranóstica , Esferoides Celulares/patologia , Linhagem Celular Tumoral , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Antineoplásicos/farmacologia , Microambiente Tumoral , Neoplasias Pancreáticas
5.
Curr Psychol ; : 1-8, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35153459

RESUMO

The COVID 19 pandemic has challenged the humankind's livelihood, physical health, mental health, employment, and economy. Lockdowns, quarantines, online teaching, and learning have become new normal. Negativities have been spread across the globe and society by the pandemic. The negative effects caused a confused mindset, fear, anxiety, stress, and other psychological complications amongst the people especially among the Health Care Workers (HCWs), children, elderly people, and Frontline Workers (FLWs). This research work examines the levels of Occupational Stress (OS), and psychological well-being (PWB) of HCWs and police personnel during the pandemic and the relationship between OS and PWB. Further, the study analyzed the role of Positive Psychological Capital (PPC) as a mediator and Emotional Quotient (EQ) as a moderator in the relationship between OS and PWB. Positive Psychological Capital (PPC) characteristics of the respondents such as having faith in one's ability, and performance, willingness to succeed or attain the goals framed, ability to bounce back from the hard times, and their optimism about the future have helped them to tackle the stress caused by the pandemic and to maintain a better state of psychological wellbeing in the fight against the pandemic.

6.
Biomed Mater ; 16(5)2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-34298521

RESUMO

Pancreatic cancer is a highly invasive disease with low survival rates. The high death rates associated with pancreatic cancer are due to multiple factors including late stage diagnosis, multi-drug resistance, invasive nature and restricted access of the therapeutic moiety to the cancer cells due to the stroma. Smart multifunctional nanocarriers that deliver the therapeutic agent in to the cancer tissue as well as enable imaging of the tissue represent an emerging paradigm in cancer therapy. Accurate and reliable detection of cancerous lesions in pancreas is essential for designing appropriate therapeutic strategy to annihilate the highly aggressive pancreatic cancer. A combination of imaging modalities can enhance the reliability of cancer detection. In this context, we report here a hybrid iron oxide-gold nanoparticle with dual contrast enhancing ability for both magnetic resonance imaging (MRI) and micro-computed tomography (micro-CT) that is co-encapsulated with the nucleotide analogue gemcitabine in a chitosan matrix. The theranostic system displayed enhanced cytotoxicity against PanC-1 pancreatic cancer cells when compared to normal cells over 48 h due to differences in cell internalization. The iron oxide-gold hybrid enabled visualization of the theranostic nanoparticle by MRI as well as micro-CT. Further, the magnetocaloric effect of the iron oxide enabled faster release of the chemotherapeutic agent as well as augmented the cytotoxicity by inducing hyperthermia. This system holds promise for further exploration as an integrated diagnostic and therapeutic platform for pancreatic cancer.


Assuntos
Meios de Contraste , Nanopartículas de Magnetita/química , Neoplasias Pancreáticas/metabolismo , Nanomedicina Teranóstica/métodos , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Meios de Contraste/química , Meios de Contraste/farmacocinética , Desoxicitidina/análogos & derivados , Desoxicitidina/química , Desoxicitidina/farmacologia , Ouro/química , Humanos , Imageamento por Ressonância Magnética , Pâncreas/metabolismo , Gencitabina
7.
Indian J Orthop ; 55(Suppl 1): 176-181, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34113426

RESUMO

BACKGROUND: In recent times due to the advancement of haemodialysis techniques, there is increase in the life span of the patients with end-stage renal disease, which tends to increase the risk of complications of bacteraemia due to skin penetration for blood access and leading to propensity for more skeletal and spinal complications. Hence, early diagnosis of spine infection and early initiation of appropriate therapy are important in ensuring successful treatment and preventing further morbidity. MATERIALS AND METHODS: The study included 22 males and 12 females who were known case of end-stage renal disease undergoing haemodialysis therapy and diagnosed with spondylodiscitis based on the clinical and radiological signs. The included patients required surgical stabilization based on the instability, neurological status, and epidural abscess, and non-responsive to medical line of treatment. To measure the degree of pain, Visual Analog Scale was used and British Medical Research Council grading system was used for motor evaluation. Radiography was undertaken one immediately and later at 1, 3, 9, and 12 months and at yearly interval thereafter. Fusion assessment was done by features of consolidation of graft and absence of loosening of implants in both anteroposterior and lateral views will be an indirect evidence of fusion in short-term follow-up. RESULT: Average age of the patients was 62 years (range 40-75 years). Twenty-two patients were male (64.7%) and twelve (35.3%) were female. Sixteen patients had diabetes mellitus and fifteen patients had chronic glomerulonephritis with various underlying causes. All patients presented with back pain with a duration range from 3 to 8 weeks. 13 patients gave a history of on/off fever which was mild grade and 3 patients with high-grade fever. Eighteen patients presented with neurological deficits. The most common organism isolated was Methicillin-Resistant Staphylococcus Aureus (MRSA). At the final follow-up, radiographs revealed a good interbody fusion in 30 of the 34 cases, with 3 cases showed delayed fusion. The mean hemoglobin (Hb) level was 8.8 g/dl and elevated total leucocyte level with mean of 14,425; mean C-reactive protein (CRP) level was 55.6 mg/dl and erythrocyte sedimentation rate (ESR) was 47.5. All patients showed improvement in back pain. Preoperatively, the VAS had a mean of 8.5; post-operatively on day 2, the mean VAS was 3.2, and on 1 month follow-up mean VAS was 2.4. CONCLUSION: In end-stage renal disease patients presenting with back pain, the diagnosis and treatment of spondylodiscitis becomes difficult. Where fever may not be a presenting feature even in cases with severe destructive osteomyelitis, and at times presenting as latent infection. Hence, spinal infection should be suspected as a possible cause of back pain in patients presenting with ESRD, even if they are presenting without fever and MRI study should be performed for the early diagnosis. Surgical intervention with debridement and posterior instrumentation should be considered as a modality of treatment in all cases of spondylodiscitis, with improved clinical outcome in terms of functionality, disability, and rehabilitation and acceptable complication rates in the perioperative period which can be adjusted to the individual cases.

9.
Indian J Ophthalmol ; 68(9): 1975-1976, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32823446

RESUMO

We report a case of a young male from Udupi, Karnataka, presenting with features of bilateral non-granulomatous anterior uveitis with mild vitritis. There was a history of fever and myalgia a month before ocular features, which was partially treated. He also gave a history of being actively involved in the flood relief work in the district, before the onset of fever. This prompted an evaluation of leptospirosis, which came positive. The possibility of leptospira uveitis needs to be considered, especially in cases of non-granulomatous uveitis after floods in areas endemic for leptospirosis, which may otherwise be wrongly labeled idiopathic.


Assuntos
Infecções Oculares Bacterianas , Leptospira , Leptospirose , Uveíte , Infecções Oculares Bacterianas/diagnóstico , Infecções Oculares Bacterianas/tratamento farmacológico , Humanos , Índia , Leptospirose/complicações , Leptospirose/diagnóstico , Leptospirose/tratamento farmacológico , Masculino , Uveíte/diagnóstico , Uveíte/tratamento farmacológico
10.
Data Brief ; 27: 104683, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31720335

RESUMO

The present data study deals with the experimental analysis of performance, emission and combustion characteristics of CI engine fuelled with corn oil methyl ester biodiesel blend as alternative fuel. A two-step trans esterification process is used to produce the biodiesel. Furthermore, a characteristics study was carried out on the extracted corn oil methyl ester biodiesel blends over conventional fuel. Three different fuel blends namely B10, B20 and B30 were chosen and the performance, emission and combustion characteristics of these are compared to that of conventional diesel fuel. Eddy current dynamometer is used load the engine from no load to maximum load condition. Using AVL DiGAS 444 N gas analyser and AVL 346 smoke meter the emissions and smoke opacity of the fuel blends and diesel were measured respectively. The experimental performance, emission and combustion data's were presented.

11.
Natl Med J India ; 32(4): 207-212, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32769240

RESUMO

Background: Medication errors have an adverse impact on the healthcare system by increasing patient morbidity and mortality. They are preventable, and educational or technology-based interventions are needed to reduce their prevalence and improve medication safety. We aimed to study the impact of a sensitization programme and a blame-free reporting tool for doctors and nurses on the prevalence and reporting of medication errors in the intensive care units (ICUs) of a tertiary care teaching hospital. Methods: This prospective interventional study was conducted in the ICUs of cardiology, medicine, paediatrics and neonatology. Baseline medication errors were detected by prescription order review and direct observation of administration of medication for 30 days. A sensitization programme was conducted for doctors and nurses in these ICUs, the results were discussed, and a blame-free medication error reporting tool was introduced. Medication charts were modified to remove the transcription process in the cardiology and paediatrics ICUs. The follow-up study was conducted for 30 days in each ICU to monitor the impact of the sensitization programme. Results: The prevalence of medication errors was found to be 334.1/1000 patient observation days. Prescription errors were the most common types of errors at 129.1/1000 patient observation days. The interventions significantly reduced the error rate in all four ICUs. The overall number of prescriptions with errors was reduced from 9.1% (177/1944) to 3.5% (48/1373) and no medication error was reported using the tool. Conclusion: The sensitization programme on medication errors for doctors and nurses may be effective in improving medication safety. The impact was more pronounced in prescription errors. Reporting of medication errors did not improve in this study despite the introduction of a blame-free reporting tool.


Assuntos
Prescrições de Medicamentos/estatística & dados numéricos , Unidades de Terapia Intensiva/estatística & dados numéricos , Erros de Medicação/prevenção & controle , Erros de Medicação/estatística & dados numéricos , Atitude do Pessoal de Saúde , Educação Médica Continuada , Pessoal de Saúde/educação , Hospitais de Ensino , Humanos , Índia , Prevalência , Estudos Prospectivos , Atenção Terciária à Saúde
12.
Indian J Occup Environ Med ; 21(2): 84-88, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29540969

RESUMO

BACKGROUND: Prevalence of cardiovascular diseases are reported to be high in police force, which constitute a special occupational group. "Partners in Prevention" was a special surveillance activity carried out among the personnel of the Department of Police, Government of Puducherry by JIPMER, Puducherry. The present study reports the prevalence of metabolic syndrome and other cardiovascular risk factors in this group. MATERIALS AND METHODS: The design was cross-sectional analytical study covering 1618 policemen during 2013-15. A pre-tested questionnaire was used for collecting data. Anthropometric and biochemical measurements were carried out using standard techniques. Metabolic syndrome was diagnosed using the International Diabetes Federation (IDF) consensus worldwide definition. Statistical analysis was performed using the IBM- SPSS 21 software. RESULTS: The mean (SD) age of the participants was 45.7 (10.1) years. Majority (90%) of the participants were males and were in the age group of 30-59 years. Metabolic syndrome was observed in two-fifth (42%) of the study population. We found the prevalence as: hypertension (45.2%), abnormal HDL levels (62.3%), diabetes (34.7.1%), and high body mass index of >=25 kg/m2 (60.5%). CONCLUSION: Our study identified that police personnel were having high CVDs and risk factors. It calls for an urgent need to initiate screening and secondary prevention programmes.

13.
J Food Sci Technol ; 51(11): 3199-207, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26396312

RESUMO

Shrimp waste is an important source of astaxanthin, which occur as a complex with proteins, and protein isolates as well as carotenoids are known to possess antioxidant activity. Investigations were carried out to optimize hydrolysis of shrimp waste using a bacterial protease to obtain antioxidant activity rich protein isolate. The effect of three process variables namely enzyme concentration to waste, incubation temperature and time on carotenoid recovery, protein content, trichloro acetic acid (TCA) soluble peptide content and DiPhenyl Picryl Hydrazylchloride (DPPH) scavenging activity was evaluated using a fractionally factorial design. A high correlation coefficient (>0.90) between the observed and the predicted values indicated the appropriateness of the design employed. Maximum carotenoid recovery was obtained by hydrolysing the shrimp waste with 0.3 % enzyme for 4 h. DPPH radical scavenging activity of carotenoprotein isolate was markedly affected by enzyme concentration, temperature and time of hydrolysis. The study indicated that in order to obtain the carotenoprotein from shrimp waste with higher carotenoid content hydrolysing with an enzyme concentration of 0.2-0.4 %, at lower temperature of 25-30° upto 4 h is ideal. However, in order to obtain the protein isolate with increased antioxidant activity hydrolysing at higher temperature of 50 °C, with higher enzyme concentration of 0.5 % for shorter duration is more ideal.

14.
Indian J Psychol Med ; 34(1): 34-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22661805

RESUMO

BACKGROUND: To study the clinical profile and co-morbidity in Indian children with attention-deficit/hyperactivity disorder (ADHD). MATERIALS AND METHODS: A prospective analytical study of 2 years duration at the Child Guidance Clinic of a pediatric tertiary care hospital in a south Indian city using Diagnostic and statistical manual of Mental Disorders-1V based questionnaires. RESULTS: Of the 251 referrals, 51 (20.3%) children met the inclusion criteria for the diagnosis of ADHD. M:F ratio was 6.3:1. The mean age was 5.7 years. A majority of the children belonged to middle and lower socio-economic class and were first-born children. Most children were brought up in nuclear families. History of delayed speech and language development was commonly seen in these children. Combined type of ADHD was the most common type. At least one co-morbid diagnosis was seen in 86.3% of children, and learning disability was the most common co-morbid diagnosis. The mean IQ was 90 (SD±12). CONCLUSION: Early markers of cognitive dysfunction like delayed speech, language and social and adaptive development may be a pointer towards the diagnosis of ADHD in children. Knowledge about their sociodemographic profile and other co-morbid conditions that are associated with ADHD is necessary to fully understand the magnitude of the problem and to plan effective therapy for them.

15.
Cancer Lett ; 281(2): 220-31, 2009 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-19321257

RESUMO

Bone morphogenetic proteins (BMP), a member of the TGF-beta superfamily, have broad activities in regulating various kinds of cellular behaviors. Previously, we have demonstrated that BMP-4 is up-regulated in human colonic adenocarcinoma and promotes the invasive phenotypes of human colorectal cancer HCT116 cells. Smad4 is a central mediator in BMP signaling pathway and it is frequently mutated in metastatic colorectal cancers. To address whether Smad4 was required for enhancing metastatic potentials by BMP-4 in colorectal cancer, we generated BMP-4 overexpressing clones from Smad4-deficient SW480 cells. The growth rate of BMP-4 overexpressing cells was slightly higher than that of empty-vector controls. Overexpression of BMP-4 resulted in an increased expression of vimentin, a marker of epithelial-mesenchymal transition, and caused the changes of cell morphology, spreading and formation of focal adhesions. BMP-4 overexpressing cells increased cell adhesion on fibronectin and collagen, and augmented cell migration and invasion potentials in comparison to empty-vector controls. The induction of cell migration by BMP-4 overexpression was inhibited by BMP-4 siRNA. To further identify the target genes of the elevated BMP-4 signaling in SW480 cells, an oligonucleotide microarray was performed. Among 46,000 genes, 91 genes (65 up-regulated and 26 down-regulated) with 2-fold difference have been identified between BMP-4 overexpressing and empty-vector cells. This study demonstrates that Smad4 is dispensable for enhanced invasiveness of human colorectal cancer cells due to BMP-4 overexpression.


Assuntos
Proteína Morfogenética Óssea 4/biossíntese , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Invasividade Neoplásica/genética , Proteína Smad4/deficiência , Western Blotting , Proteína Morfogenética Óssea 4/genética , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Neoplasias Colorretais/genética , Imunofluorescência , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Interferente Pequeno , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vimentina/biossíntese
16.
Int J Clin Exp Med ; 1(2): 117-29, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19079666

RESUMO

Radiofrequency ablation (RFA) is gaining popularity for treating colorectal liver metastases by inducing image guided tumor hyperthermia. In order to reduce tumor recurrence, adjuvant therapies have been administered post-RFA. We hypothesized that tumor cells escaping RFA cytotoxicity by being in the sublethal zones of tumor might develop differential behavior toward cytotoxic drugs. Here, we used cultured human colorectal cancer cells to evaluate the interaction between heat treatment and chemotherapeutic agents. Human colon cancer cell lines HT29 and HCT116 were subjected to temperatures of 42 degrees to 50 degrees C for 15 min, in combination with 5-fluorouracil, oxaliplatin, or irinotecan at different sequences. Cytotoxicity was determined by MTT assay. The cell cycle progression was analyzed by flow cytometry with propidium iodide staining. The expression of several genes associated with drug sensitivity was quantitated by real-time RT-PCR before and after heat treatment. Either heat treatment at 45 degrees C by simultaneous or pre-treatment with three different chemotherapeutic agents didn't affect the cytotoxicity of the combined treatment to HT29 and HCT116 cells, except for irinotecan treatment in HCT116 cells. However, when pre-exposure to 45 degrees C, HCT116 cells, but not HT29 cells, developed resistance to these three drugs. In an analysis of cell cycle profile after the drug followed heat treatment, a longer delay in cell cycle progression in HCT116 cells was observed in comparison to HT29 cells. Furthermore, HCT116 and HT29 cells exhibited different expression profiles of several drug-related genes in response to heat treatment at 45 degrees C. An observation of a differential response to the drug and heat treatment sequences between two human colon cancer cell lines suggests that tumor heterogeneity and selection of chemotherapeutic agents need to be under consideration in the clinical setting.

17.
Cancer Lett ; 256(2): 207-17, 2007 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-17640799

RESUMO

Cancer thermotherapy and radiofrequency ablation (RFA) have been adopted as modalities for treating various kinds of cancer. We have previously demonstrated that bone morphogenetic protein-4 (BMP-4) is up-regulated in colonic adenocarcinoma. Here, we investigated whether an increase of BMP-4 expression changes cellular response to heat treatment in human colon cancer HCT116 cells. BMP-4 overexpressing HCT116 cells generated by stable transfection showed a significantly increased survival rate and a decreased apoptotic rate in comparison to empty vector controls after heat treatment at 45 degrees C for 20min. The expression levels and pattern of HSP90, HSP70, and HSP27 after heat treatment were similar between these two cell lines. There was no difference in expression levels of Bcl-2 and Bax in these two cell lines and their expression remained unchanged after heat treatment. Both activities of the extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) were stimulated by heat in these cells. Comparatively, BMP-4 overexpressing cells had an intense and prolonged ERK activation, while a less intense and short JNK activation. Correspondingly, treatment of BMP-4 overexpressing cells with noggin, a BMP-4 antagonist, resulted in a reduction of heat-activated ERK but an increase of heat-activated JNK and significantly increased heat-induced apoptotic rate. These results indicate that BMP-4 can protect colon cancer cells from heat-induced apoptosis through enhancing the activation of ERK as well as inhibiting the activation of JNK.


Assuntos
Adenocarcinoma/terapia , Apoptose , Proteínas Morfogenéticas Ósseas/metabolismo , Neoplasias do Colo/terapia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Hipertermia Induzida , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Transdução de Sinais , Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Apoptose/efeitos dos fármacos , Proteína Morfogenética Óssea 4 , Proteínas Morfogenéticas Ósseas/genética , Proteínas de Transporte/metabolismo , Sobrevivência Celular , Neoplasias do Colo/enzimologia , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Flavonoides/farmacologia , Células HCT116 , Proteínas de Choque Térmico HSP27 , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Choque Térmico/metabolismo , Humanos , Chaperonas Moleculares , Proteínas de Neoplasias/metabolismo , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção , Regulação para Cima , Proteína X Associada a bcl-2/metabolismo
18.
Exp Cell Res ; 313(5): 1033-44, 2007 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-17275810

RESUMO

Bone morphogenetic protein (BMP), a member of the TGF-beta superfamily, is involved in development, morphogenesis, cell proliferation and apoptosis. Dysregulation of BMP signaling has been suggested in tumorigenesis. In an analysis of human colon normal mucosa and tumors at different stages by immunohistochemistry, we observed that the intensity of BMP-4 staining in late-adenocarcinomas was stronger than that in normal mucosa and adenomas, while there was no difference in the staining of its receptors (BMPR-IA and BMPR-II) at all stages. The up-regulation of BMP-4 was further validated in another panel of tumor tissues by real-time RT-PCR, showing that BMP-4 mRNA levels in primary colonic carcinomas with liver metastasis were significantly higher than that in the matched normal mucosa. In order to understand the functional relevance of BMP-4 expression in colon cancer progression, BMP-4-overexpressing cell clones were generated from HCT116 cells. Overexpression of BMP-4 did not affect the HCT116 cell growth. The cells overexpressing BMP-4 became resistant to serum-starvation-induced apoptosis and exhibited enhanced migration and invasion characteristics. Overexpression of BMP-4 changed cell morphology to invasive spindle phenotype and induced the expression and activity of urokinase plasminogen activator (uPA). These results indicate that BMP-4 confers invasive phenotype during progression of colon cancer.


Assuntos
Adenocarcinoma/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Movimento Celular , Neoplasias do Colo/metabolismo , Mucosa Intestinal/metabolismo , Neoplasias Hepáticas/secundário , Adenocarcinoma/patologia , Apoptose , Proteína Morfogenética Óssea 4 , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Neoplasias do Colo/patologia , Sistemas Computacionais , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/metabolismo , Reação em Cadeia da Polimerase , Análise Serial de Proteínas , RNA Mensageiro/metabolismo , Transfecção , Regulação para Cima , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
19.
Ann Burns Fire Disasters ; 19(3): 123-9, 2006 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-21991036

RESUMO

Low molecular weight heparin (LMWH) appears to be a promising solution for reducing inflammatory post-burn episodes and results in improved healing. The clinical examination presented here includes patients with burn wounds ranging from 20 to 35% total body surface area (TBSA) who were categorized into two groups, of which one received subcutaneous LMWH treatment (10,000 units/day) and the other acted as control. The process of healing was assessed through regular examination of clinical features such as regression of erythema and oedema, eschar formation, and rate of re-epithelialization. Various studies have demonstrated an increase in levels of serum IL-6 indicating the severity of the morbid condition. In the present investigation, LMWH-treated patients exhibited a faster decline in levels of serum IL-6 (within 12 days) than control. Infiltration of inflammatory cells at the local wound site was assessed through a histological analysis of tissue samples taken on various days during the healing process. The LMWH-treated groups exhibited an organized healing pattern with better remodelling in a shorter duration (28 days), while control patients took more than 28 days for complete healing. A slight correlation was observed with TBSA to the inflammatory process, which subsided in patients treated with LMWH, favourably modulating the events involved in the inflammatory process of burn wound healing.

20.
Ann Surg Oncol ; 12(9): 743-52, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16078010

RESUMO

BACKGROUND: Cryotherapy is a method of in situ destruction of tumors by freeze/thaw mechanisms. Cancer cells located in the peripheral zone of the tumor undergoing cryotherapy can die by apoptosis. We hypothesized that p21WAF1 is involved in the mediation of cryotherapy-induced apoptosis. METHODS: HT29 cells grown on a plate were subjected to -10 degrees C and returned to 37 degrees C for various periods of time. Cells were analyzed by flow cytometry, Western blot, and reverse transcriptase-polymerase chain reaction for determining cell-cycle distribution, p21WAF1 protein expression, and messenger RNA levels, respectively. The p21WAF1 expression in nude mouse tumor xenografts after cryotherapy was examined by immunofluorescence staining. A series of the p21WAF1 promoter cloned into a luciferase reporter vector were transfected into HT29 cells for identifying the response element to cryoinjury. Antisense oligodeoxynucleotide (ODN) was applied to examine the effect of p21WAF1 expression on cryotherapy-induced apoptosis. RESULTS: Both protein and messenger RNA of p21WAF1 were induced by cryoinjury in cultured cells and tumor xenografts. Deletion analysis of the p21WAF1 promoter revealed that a region from -121 to -95 base pairs was responsible for the activation and that this activation was p53 independent. HT29 cells arrested at the G1 phase after cryoinjury. The cryotherapy-induced apoptotic rate in HT29 cells was increased in the presence of antisense p21WAF1 ODN in comparison to the random ODN. CONCLUSIONS: Induction of p21WAF1 increases tumor cell survival and may result in recurrences at treated sites after cryotherapy. Combining antisense ODN targeted against p21WAF1 and cryotherapy may improve clinical outcomes in the treatment of colorectal cancer.


Assuntos
Apoptose/efeitos dos fármacos , Crioterapia , Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Terapia Genética/métodos , Oligodesoxirribonucleotídeos Antissenso/uso terapêutico , Apoptose/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células HT29 , Humanos
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