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1.
Clin Neurophysiol ; 132(11): 2827-2839, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34592560

RESUMO

OBJECTIVE: While previous studies showed that the single nucleotide polymorphism (Val66Met) of brain-derived neurotrophic factor (BDNF) can impact neuroplasticity, the influence of BDNF genotype on cortical circuitry and relationship to neuroplasticity remain relatively unexplored in human. METHODS: Using individualised transcranial magnetic stimulation (TMS) parameters, we explored the influence of the BDNF Val66Met polymorphism on excitatory and inhibitory neural circuitry, its relation to I-wave TMS (ITMS) plasticity and effect on the excitatory/inhibitory (E/I) balance in 18 healthy individuals. RESULTS: Excitatory and inhibitory indexes of neurotransmission were reduced in Met allele carriers. An E/I balance was evident, which was influenced by BDNF with higher E/I ratios in Val/Val homozygotes. Both long-term potentiation (LTP-) and depression (LTD-) like ITMS plasticity were greater in Val/Val homozygotes. LTP- but not LTD-like effects were restored in Met allele carriers by increasing stimulus intensity to compensate for reduced excitatory transmission. CONCLUSIONS: The influence of BDNF genotype may extend beyond neuroplasticity to neurotransmission. The E/I balance was evident in human motor cortex, modulated by BDNF and measurable using TMS. Given the limited sample, these preliminary findings warrant further investigation. SIGNIFICANCE: These novel findings suggest a broader role of BDNF genotype on neurocircuitry in human motor cortex.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Potenciais Pós-Sinápticos Excitadores/fisiologia , Potenciais Pós-Sinápticos Inibidores/fisiologia , Córtex Motor/fisiologia , Plasticidade Neuronal/fisiologia , Polimorfismo de Nucleotídeo Único/genética , Adulto , Eletromiografia/métodos , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Masculino , Metionina/genética , Estimulação Magnética Transcraniana/métodos , Valina/genética
2.
South Asian J Cancer ; 10(4): 213-219, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34984198

RESUMO

Breast cancer is a public health challenge globally as well as in India. Improving outcome and cure requires appropriate biomarker testing to assign risk and plan treatment. Because it is documented that significant ethnic and geographical variations in biological and genetic features exist worldwide, such biomarkers need to be validated and approved by authorities in the region where these are intended to be used. The use of western guidelines, appropriate for the Caucasian population, can lead to inappropriate overtreatment or undertreatment in Asia and India. A virtual meeting of domain experts discussed the published literature, real-world practical experience, and results of opinion poll involving 185 oncologists treating breast cancer across 58 cities of India. They arrived at a practical consensus recommendation statement to guide community oncologists in the management of hormone positive (HR-positive) Her2-negative early breast cancer (EBC). India has a majority (about 50%) of breast cancer patients who are diagnosed in the premenopausal stage (less than 50 years of age). The only currently available predictive test for HR-positive Her2-negative EBC that has been validated in Indian patients is CanAssist Breast. If this test gives a score indicative of low risk (< 15.5), adjuvant chemotherapy will not increase the chance of metastasis-free survival and should not be given. This is applicable even during the ongoing COVID-19 pandemic.

3.
J Assist Reprod Genet ; 37(7): 1567-1577, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32594284

RESUMO

PURPOSE: The state of limited resource settings that Coronavirus (COVID-19) pandemic has created globally should be taken seriously into account especially in healthcare sector. In oncofertility, patients should receive their fertility preservation treatments urgently even in limited resource settings before initiation of anticancer therapy. Therefore, it is very crucial to learn more about oncofertility practice in limited resource settings such as in developing countries that suffer often from shortage of healthcare services provided to young patients with cancer. METHODS: As an extrapolation during the global crisis of COVID-19 pandemic, we surveyed oncofertility centers from 14 developing countries (Egypt, Tunisia, Brazil, Peru, Panama, Mexico, Colombia, Guatemala, Argentina, Chile, Nigeria, South Africa, Saudi Arabia, and India). Survey questionnaire included questions on the availability and degree of utilization of fertility preservation options in case of childhood cancer, breast cancer, and blood cancer. RESULTS: All surveyed centers responded to all questions. Responses and their calculated oncofertility scores showed different domestic standards for oncofertility practice in case of childhood cancer, breast cancer, and blood cancer in the developing countries under limited resource settings. CONCLUSIONS: Medical practice in limited resource settings has become a critical topic especially after the global crisis of COVID-19 pandemic. Understanding the resources necessary to provide oncofertility treatments is important until the current COVID-19 pandemic resolves. Lessons learned will be valuable to future potential worldwide disruptions due to infectious diseases or other global crises.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/prevenção & controle , Atenção à Saúde/normas , Preservação da Fertilidade/métodos , Neoplasias/terapia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Betacoronavirus/isolamento & purificação , COVID-19 , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Atenção à Saúde/economia , Países em Desenvolvimento , Feminino , Preservação da Fertilidade/economia , Preservação da Fertilidade/estatística & dados numéricos , Humanos , Neoplasias/virologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , SARS-CoV-2 , Inquéritos e Questionários
4.
Indian J Cancer ; 54(1): 161-163, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29199681

RESUMO

INTRODUCTION: Lung cancer is most common cause of cancer death in the world. Most of the patient are diagnosed in the late stages and receive only palliative treatment. The main objective of the palliative chemotherapy is to improve survival as well as the quality of life (QOL). QOL is the most neglected dimension of cancer care in developing countries like India. Palliative chemotherapeutic agent which has minimum toxicity and prolongs the survival of metastatic cancer patients is the need of the day. MATERIALS AND METHODS: In this study, 43 metastatic adenocarcinoma of lung patients of South Indian origin were enrolled. Twenty patients out of this 43 were epidermal growth factor receptor (EGFR) mutation positive and were started on tyrosine kinase inhibitor (TKI). Rest 23 patients were EGFR mutation negative and were started on various platinum-based doublet chemotherapy. QOL was measured using Cancer Institute QOL Questionnaire version 2 at the beginning of therapy and at the end of 3 months. RESULTS: Our study showed that metastatic lung cancer patients had average QOL at presentation. The QOL in patients on TKI improved compared to those on platinum doublet chemotherapy during the second assessment, but this improvement was statistically not significant. CONCLUSION: In this study, the metastatic lung cancer patients had an average QOL during initial presentation. Patients on TKI had a trend toward better QOL after 3 months of treatment compared to platinum doublet chemotherapy.


Assuntos
Carboplatina/efeitos adversos , Receptores ErbB/genética , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica , Intervalo Livre de Doença , Feminino , Humanos , Índia/epidemiologia , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Metástase Neoplásica , Estadiamento de Neoplasias , Inibidores de Proteínas Quinases/efeitos adversos , Proteínas Tirosina Quinases/antagonistas & inibidores , Qualidade de Vida
5.
J Mech Behav Biomed Mater ; 63: 352-360, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27450037

RESUMO

Copper is a well proven antimicrobial material which can be used in the form of a coating on the touch surfaces. Those coating can offer a good service as touch surface for very long time if only they possess good mechanical properties like scratch resistance and microhardness. In the present work the above mentioned mechanical properties were determined on the electrodeposited copper thin film; deposited on double zincated aluminium. During deposition, current density was varied from 2Adm(-2) to 10Adm(-2), to produce crystallite size in the range of 33.5nm to 66nm. The crystallite size was calculated from the X-ray peak broadening (Scherrer׳s formula) which were later confirmed by TEM micrographs. The scratch hardness and microhardness of the coating were measured and correlated with the crystallite size in the copper coating. Both characteristic values were found to increase with the reduction in crystallite size. Reduced crystallite size (Hall-Petch effect) and preferred growth of copper films along (111) plane play a significant role on the increase in the hardness of the coating. Further, TEM analysis reveals the presence of nano-twins in the film deposited at higher current density, which contributed to a large extent to the sharp increase of coating hardness compared to the mechanism of Hall-Petch effect. The antimicrobial ability of the coated sample has been evaluated against Escherichia coli bacteria and which is compared with that of commercially available bulk copper using the colony count method. 94% of E. coli cells were died after six hours of exposure to the copper coated surface. The morphology of the copper treated cells was studied using SEM.


Assuntos
Anti-Infecciosos/análise , Materiais Revestidos Biocompatíveis/análise , Cobre/química , Galvanoplastia , Escherichia coli/efeitos dos fármacos , Dureza
6.
Artigo em Inglês | MEDLINE | ID: mdl-27003743

RESUMO

The intestinal mucosal barrier contributes to homeostasis by limiting systemic dissemination of microbes and toxins while allowing nutrients to pass through to the systemic circulation. In a recent issue of Science, Spadoni et al. demonstrated a novel mechanism to enable this selectivity: the existence of a gut-vascular barrier (GVB) as indicated by a series of studies on the interaction between murine and human intestine with Salmonella typhimurium species . They showed that (i) enteroglial cells and pericytes in contact with endothelial cells (ECs) form the GVB (ii) Salmonella typhimurium can penetrate it by a mechanism dependent on the pathogenicity island (Spi) 2-encoded type III secretion system and on decreased ß-catenin dependent signaling in gut endothelial cells. Understanding the GVB may provide new insights into the regulation of the gut-liver axis.


Assuntos
Permeabilidade Capilar/imunologia , Intestinos/imunologia , Intestinos/microbiologia , Microbiota/imunologia , Infecções por Salmonella/imunologia , Salmonella typhimurium/imunologia , Animais , Humanos
7.
J Nat Sci Biol Med ; 6(1): 239-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25810673

RESUMO

We report the case of a 29-year-old male who presented with vague right upper quadrant pain, 8 years following a pancreaticoduodenectomy for a symptomatic pancreatic islet cell tumor. Subsequent imaging revealed multiple lesions in the right lobe of the liver. A diagnosis of metastatic disease could not be out ruled and hence a formal resection was performed. A formal retrospective review of case notes, preoperative imaging, operative notes, subsequent histology as well as a review of the current literature using the Medline, CINAHL, and EMBASE databases was performed. Histologic analysis showed these lesions to be hepatocellular adenomas. We highlight in this case the importance of preoperative imaging and workup, discuss hepatocellular adenomas in males and hypothesize as to the underlying pathophysiology in this particular case based on the available evidence.

8.
Ann Oncol ; 26(6): 1170-1174, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25701453

RESUMO

BACKGROUND: Combination chemotherapy ABVD (doxorubicin, bleomycin, vinblastine and dacarabazine) cures ∼70% of patients with advanced Hodgkin's lymphoma (aHL, stages IIB, III and IV) while more toxic escalated BEACOPP (EB, combination of bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine and prednisolone) increases cure rates to 85%. Patients with a positive interim positron emission tomography-computerized tomography (PET-CT) scan after two cycles (PET-2) of ABVD have very poor outcomes with continued ABVD. Intensifying therapy with EB in PET-2-positive patients ('response-adapted therapy') may improve cure rates, whereas the negative patients can continue ABVD alone. PATIENTS AND METHODS: Eligible patients with newly diagnosed aHL received two cycles of ABVD and underwent PET-2 (scored with semi-quantitative 5-point visual criteria, 'Deauville score'). PET-2-negative patients continued four additional cycles of ABVD, whereas PET-2-positive patients received four cycles of EB. A phase II sample size of 50 was estimated keeping the lower and higher proportion of rejection of the event-free survival (EFS) as 70% and 85%, respectively. RESULTS: Fifty patients [median age 28 (12-60) years; male : female: 39 : 11; stages: IIB-3 (6%), III-29 (58%) and IV-18 (36%); International Prognostic Score (IPS): 0-3: 34 (68%); 4-7: 16 (32%)] were enrolled; 49 underwent PET-2. Eight (16%) were PET-2-positive, whereas 41 (84%) were negative. Forty-seven were evaluable for EFS and all 50 for overall survival (OS). The 2-year EFS was 76% (95% CI: 68-83) and OS was 88% (95% CI: 82-94). PET-2 was strongly prognostic-2-year EFS, negative versus positive: 82% versus 50%; P = 0.013. CONCLUSION: PET-2 response-adapted strategy could not achieve EFS of 85% in aHL. However, escalated therapy improved outcomes in PET-2-positive patients compared with historical data. TRIAL REGISTRATION: CTRI/2012/06/002741 (http://www.ctri.nic.in) and NCT01304849 (http://www.clinicaltrials.gov).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Doença de Hodgkin/tratamento farmacológico , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bleomicina/administração & dosagem , Bleomicina/efeitos adversos , Criança , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Dacarbazina/administração & dosagem , Dacarbazina/efeitos adversos , Progressão da Doença , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Doença de Hodgkin/diagnóstico por imagem , Humanos , Índia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Procarbazina/administração & dosagem , Procarbazina/efeitos adversos , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Vimblastina/administração & dosagem , Vimblastina/efeitos adversos , Vincristina/administração & dosagem , Vincristina/efeitos adversos , Adulto Jovem
9.
Indian J Cancer ; 52(3): 266-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26905105

RESUMO

INTRODUCTION: Tyrosine kinase inhibitors have revolutionized the treatment of metastatic lung cancer in patients with epidermal growth factor receptor (EGFR) mutations. Amplified refractory mutation system (ARMS)-reverse transcription-polymerase chain reaction (RT-PCR), the current standard for detecting EGFR mutation status is time-consuming and highly expensive. Consequently any surrogate test which are cheaper, faster and as accurate as the PCR method will help in early diagnosis and management of patients with lung cancer, especially in resource-limited settings. MATERIALS AND METHODS: Eighty-five patients, all of South Indian origin, with adenocarcinoma of lung, registered between October 2009 and January 2013, were evaluated for EGFR mutation status by using scorpion probe based ARMS RT-PCR method. Immunohistochemical (IHC) was performed using the phosphorylated AKT (P-AKT) and thyroid transcription factor-1 (TTF-1) on above patient's sample, and the results were compared with EGFR mutation tests. RESULTS: EGFR mutation was positive in 34 of 85 patients (40%). P-AKT and TTF-1 were positive in 50 (58.8%) and 68 (80%) patients respectively. Both P-AKT and TTF-1 had statistically significant correlation with EGFR mutation status. Positive and negative predictive value of P-AKT in diagnosing EGFR mutation was 58% and 85.5% and that for TTF-1 was 48.5% and 94.1%, respectively. The problem of low positive predictive value can partly be overcome by testing P-AKT and TTF-1 simultaneously. CONCLUSION: P-AKT and TTF-1 using IHC had statistically significant correlation with EGFR mutation with high negative predictive value. In the case of urgency of starting treatment, EGFR mutation testing may be avoided in those patients who are negative for these IHC markers and can be started on chemotherapy.


Assuntos
Adenocarcinoma/genética , Biomarcadores , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Proteínas Nucleares/genética , Proteína Oncogênica v-akt/genética , Fatores de Transcrição/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Adulto , Idoso , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Fosforilação , Reação em Cadeia da Polimerase , Prognóstico , Fator Nuclear 1 de Tireoide
10.
Int J Surg ; 12(8): 864-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25026310

RESUMO

BACKGROUND: Involvement of the inferior vena cava (IVC) by neoplasm has traditionally been considered a contra-indication to curative surgery because of high surgical risks and poor long-term prognosis. Advances in surgical and anaesthetic techniques however have made this feasible. The aim of this study is to evaluate the outcome of combined IVC and visceral resection in a single institution. METHODS: A retrospective review of a prospectively maintained database was performed. Pre-operative clinicopathological data, operative details and post-operative outcomes including overall and disease-free survival were analysed. Clinicopathological data of patients over a seven-year period undergoing combined IVC and visceral resection was reviewed, including overall and disease-free survival. RESULTS: Between 2006 and 2012, 14 patients underwent IVC resection was accompanied by major hepatectomy (8), nephrectomy (6) and multivisceral resection (3). Post resection, the IVC was reconstructed primarily (3); with PTFE tube graft (9) or using a Gore-tex patch graft (2). All patients underwent a R0 resection. There were two postoperative deaths within 30 days. 6 patients had postoperative complications. There was 1 early and one late (after 6 months) IVC thrombosis. With a median follow up of 20 months (range 5-84 months), two patients died of tumour recurrence and ten are alive with (n = 5) or without (n = 5) disease. CONCLUSION: Combined IVC and visceral resection can be safely performed in selected patients. Surgery provides the possibility of negative margins, acceptable perioperative morbidity/mortality and prolonged survival. These factors combined with lack of alternative treatments justify this approach. However, specialist teams should perform the surgery preferably in centres with expertise in liver transplantation.


Assuntos
Neoplasias Abdominais/cirurgia , Hepatectomia/estatística & dados numéricos , Nefrectomia/estatística & dados numéricos , Veia Cava Inferior/cirurgia , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Complicações Pós-Operatórias , Estudos Retrospectivos
11.
Indian J Psychiatry ; 51(3): 191-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19881046

RESUMO

BACKGROUND: Hamilton depression rating scale (Ham-D) is the most widely used clinician rating scale for depression. There has been no Indian study that has examined the inter-rater reliability (IRR) of video-recorded interviews of the 21-item Ham-D. AIM: To study the IRR of scoring video-recorded interviews for 21-item Ham-D. MATERIALS AND METHODS: Eighteen subjects with major depressive disorder involved in a larger study were interviewed using the semi-structured clinical interview of the 21-item Ham-D by a primary rater after informed consent. These interviews were video-recorded and portions edited to ensure rater blinding. Subsequently, the video-recorded interviews were rated by a "blind" rater. Both rated the different sub-domains of Ham-D according to Rhoades and Overall (1983). IRR was evaluated using intra-class correlation coefficient. RESULTS: Excellent IRR was observed (0.9891) between the two raters. This was true for each of the primary factors and super-factors. CONCLUSION: Video recorded 21-item Ham-D has excellentIRR. Video-recorded interviews of Ham-D can be reliably used to blind raters in research.

12.
Indian J Surg ; 70(1): 40-1, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23133016

RESUMO

Lipomas are one of the most common benign mesenchymal tumors in the body. Usually asymptomatic, they rarely warrant treatment unless they attain enormous size causing cosmetic deformity or pressure effects. Head and neck region is an uncommon site, retropharyngeal space being one of the rarest. Lipomas in this region can produce pressure symptoms demanding surgical excision.This is a case report of retropharyngeal lipoma, extending from skull base to the clavicle. Though tumor was present for 20 yrs it exhibited rapid growth over a period of 2-3 yrs causing respiratory obstruction, dysphagia & dysphonia. Clinically the entire laryngopharynx, trachea and carotid sheath were pushed anteriorly. On imaging, it showed classical features of a lipomatous mass. Patient underwent complete excision which presented a surgical challenge to surgeon and the anaesthetist from intubation to extubation.

13.
Natl Med J India ; 20(1): 13-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17557516

RESUMO

BACKGROUND: Parathyroid adenoma is the most common cause of primary hyperparathyroidism. Conventional surgical management includes bilateral neck exploration with removal of the adenoma(s) and biopsy of one of the other glands with visualization of all glands. It is associated with a risk of permanent hypoparathyroidism. Radioguided excision of parathyroid adenoma is a widely accepted technique which provides accurate localization and complete excision of the lesion with low morbidity. We report our experience with this technique. METHODS: We performed radioguided excision of parathyroid adenomas in 15 patients. All of them had preoperative localization of the adenoma using a dual tracer, dual phase 99mTc-Sestamibi scan. A dose of 8-10 mCi of 99mTc-Sestamibi was injected intravenously 2 hours before surgery. Under local anaesthesia, surgical excision of the lesion was done after localizing it using a hand-held gamma probe. Complete excision was confirmed by frozen. section of the excised lesion and an intraoperative quick parathormone assay. RESULTS: The 99mTc-Sestamibi scan revealed an increased uptake by the adenoma in all patients and complete excision was possible in all the patients. Frozen section confirmed the diagnosis and the quick parathormone assay (within 15 minutes) revealed a drop in parathormone levels to < 50% after excision in all of them. Three patients developed hypocalcaemia postoperatively and were treated with intravenous calcium supplementation. At a follow up of 2-29 months, all the patients were normocalcaemic. The renal functions improved in 2 of 6 patients who had renal failure. CONCLUSION: Minimally invasive radioguided excision of parathyroid adenomas is a simple, safe and effective technique associated with a low morbidity and can be done as a day-care procedure.


Assuntos
Hiperparatireoidismo Primário/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos , Neoplasias das Paratireoides/cirurgia , Adulto , Feminino , Humanos , Hiperparatireoidismo Primário/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Neoplasias das Paratireoides/diagnóstico por imagem , Estudos Prospectivos , Cintilografia , Fatores de Risco , Tecnécio Tc 99m Sestamibi
14.
Cell Prolif ; 40(1): 125-41, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17227300

RESUMO

OBJECTIVES: The aim of the current study was to investigate whether nicotine treatment would induce the proliferation of isolated rat primary pancreatic acinar cells in culture by activating mitogen-activated protein kinase (MAPK) signalling and exocrine secretion. MATERIALS AND METHODS: A nicotine dose- and time-response curve was initially developed to determine the optimal dose and time used for all subsequent studies. Proliferation studies were conducted by cell counting and confirmed further by bromodeoxyuridine (BrdU) incorporation and flow cytometry assays. MAPK signalling studies were conducted by Western blot analysis. Localization of ERK1/2 signals, with or without nicotine and the MAPK inhibitor, was visualized by immunofluorescence. RESULTS: Nicotine treatment caused dose-dependent activation of extracellular signal-regulated kinases (ERK1/2), the maxima occurring at 100 micro m and at 3 min after treatment; the response was suppressed by the ERK1/2 inhibitor. Maximal nicotine-induced cell proliferation occurred at 24 h, and UO126-treatment significantly reduced this response. Exposure of cells to 100 microm nicotine for 6 min significantly enhanced both baseline and cholecystokinin-stimulated cell function, and these effects were not affected by treatment with the inhibitor of ERK1/2 but were suppressed by mecamylamine, a nicotinic receptor antagonist. CONCLUSIONS: Our results suggest that nicotine treatment induced cell proliferation of isolated pancreatic acinar cells and that this is coupled with the activation of MAPK signalling with no effect on its function. Hence, in primary cells, the mechanism of induction and regulation of these two processes, cell proliferation and cell function, by nicotine treatment are independent of each other.


Assuntos
Amilases/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Nicotina/farmacologia , Pâncreas/efeitos dos fármacos , Transdução de Sinais , Animais , Proliferação de Células , Células Cultivadas , Relação Dose-Resposta a Droga , Ativação Enzimática , Citometria de Fluxo , Masculino , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Pâncreas/citologia , Pâncreas/metabolismo , Fosforilação , Ratos , Ratos Sprague-Dawley
15.
Indian J Pediatr ; 73(8): 735-7, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16936371

RESUMO

Though surgical resection is the main stay of treatment for childhood hepatoblastoma (HB), many are unsuitable for radical surgery at diagnosis due to extensive intrahepatic and/or extra hepatic disease. We report experience in five patients of HB from a single institution (2001-2005) with preoperative Neoadjuvant chemotherapy (NACT) followed by surgery. Three patients received cisplatin, doxorubicin; and two cisplatin / vincristine /5-fluorouracil. All showed more than 50% reduction in tumor size confirmed by CT scan. Hepatic resection R0 was performed in all. There was no chemotherapy related toxicity nor post surgical morbidity or mortality. All are disease free at median follow up of 4 years. NACT produces adequate down staging of the HB with acceptable toxicity. Though cisplatin with doxorubicin produced good results, new protocol with cisplatin, vincristine and 5FU is promising without cardiotoxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hepatoblastoma/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Terapia Neoadjuvante , Pré-Escolar , Hepatectomia , Hepatoblastoma/cirurgia , Humanos , Lactente , Neoplasias Hepáticas/cirurgia , Masculino
17.
Hybridoma ; 19(5): 355-61, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11128024

RESUMO

Erythroid cell stimulating factor (ESF) is present in mouse serum and has been reported to function in concert with erythropoietin (EPO) in the formation of erythroid cells in in vitro culture systems. We report here the generation and characterization of a monoclonal antibody (MAb) directed against ESF, with potent anti-ESF-neutralizing activity. A hybridoma-producing MAb to ESF was selected following enzyme-linked immunosorbent assay (ELISA)-based screening of 270 colonies obtained from a fusion of immunized mouse splenocytes with NS1 myeloma cells. Western blot analyses of mouse serum using this antibody specifically detected a single protein (approximate molecular weight of 60 kDa and 120 kDa, under reducing and nonreducing conditions, respectively) corresponding to ESF, with no reactivity to EPO. Furthermore, this MAb demonstrated reactivity to a protein similar in molecular mass, across species, showing reactivity in sera obtained from human, horse, goat, guinea pig, rabbit, and rat. Immuno-chemical characterization demonstrated this antibody to be of IgG3 isotype, bearing kappa light chains. Injection of this monoclonal anti-ESF antibody to exhypoxic polycythemic mice at 6 and 24 h after EPO injection significantly reduced 59Fe incorporation into red blood cells, demonstrating its ability to neutralize in vivo erythropoiesis in our mouse model system. Thus, this novel erythroid cell-specific MAb will be an invaluable tool for further delineating the physiological role of ESF in in vivo erythropoiesis.


Assuntos
Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Fatores Estimuladores de Colônias/imunologia , Células Precursoras Eritroides/fisiologia , Eritropoese , Animais , Anticorpos Monoclonais/administração & dosagem , Especificidade de Anticorpos , Fatores Estimuladores de Colônias/administração & dosagem , Ensaio de Imunoadsorção Enzimática , Eritropoetina/imunologia , Humanos , Hibridomas , Imunização , Camundongos , Testes de Neutralização , Policitemia/imunologia , Coelhos , Ratos
18.
J Gerontol A Biol Sci Med Sci ; 53(3): M169-75, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9597047

RESUMO

BACKGROUND: As assessed by flow cytometry, the increase in hydrogen peroxide in individual neutrophils from old volunteers was significantly greater than in neutrophils from young volunteers. To explain the discrepancy in previous reports that showed reduced superoxide generation with age and our finding, we measured the kinetics of antioxidative enzymes. METHODS: Neutrophils were obtained from young (ages 21-34) and old (ages over 65) volunteers. The increase in hydrogen peroxide following stimulation with formyl peptide in individual neutrophils was assessed by flow cytometry by using dihydrorhodamine 123. The enzyme kinetics was determined from the best fit curve using Michaelis-Menten equations. RESULTS: Aging was associated with a significant reduction in the Vmax for glutathione peroxidase. The decreased activity was not due to selenium deficiency as the serum and neutrophil concentrations were identical with age. Following activation, a significant increase in the Km was noted in neutrophils from young but not from old volunteers. CONCLUSIONS: These results account for the increased intracellular accumulation of hydrogen peroxide as a function of age in stimulated neutrophils. These results provide evidence in humans of an age-related impairment in antioxidative defense mechanisms that support the free radical theory of aging.


Assuntos
Envelhecimento/sangue , Glutationa Peroxidase/sangue , Peróxido de Hidrogênio/sangue , Ativação de Neutrófilo/fisiologia , Neutrófilos/fisiologia , Adulto , Idoso , Feminino , Citometria de Fluxo , Humanos , Cinética , Masculino , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Selênio/sangue , Superóxido Dismutase/sangue
19.
Br J Haematol ; 95(4): 596-604, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8982032

RESUMO

Previous studies have shown that the haemopoietically active murine long-term bone marrow culture (LTBMC) is a useful model for studying drug-induced suppression and recovery of myelopoiesis. We studied the effects on stromal morphology and stromal progenitors, assessed as colony forming unit-fibroblasts (CFU-F), of the addition of either the antimetabolite methotrexate (MTX) or the betalactam ceftazidime (CEF) to LTBMC. The examination of 500 micrograms/ml CEF-treated cultures revealed a stroma that appeared empty, with modest reduction in total stromal counts, and significant decreases in fat-containing and endothelial cells. In contrast, treatment with 1 microM MTX for 1 week initially caused minimal morphologic stromal changes, thereafter total stromal cell count as well as fibroblastoid, endothelial, fat containing and macrophage cells significantly increased. Haemopoiesis and the stroma recovered. Both CEF and MTX reversibly suppressed stromal progenitor cells in LTBMC. When added directly to CFU-F cultures, the concentrations resulting in a 50% colony growth inhibition were 214 micrograms/ml for CEF and 375 nM for MTX. These results suggest that CEF, but not MTX, has direct toxic effects on the stroma of established LTBMC. Stromal cell increase following MTX treatment probably indicates a stromal response that may contribute to haemopoietic cell recovery.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Células da Medula Óssea , Ceftazidima/farmacologia , Células-Tronco Hematopoéticas/citologia , Metotrexato/farmacologia , Animais , Transplante de Medula Óssea , Contagem de Células , Divisão Celular , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Fibroblastos/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL
20.
Am J Hematol ; 52(3): 178-83, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8756083

RESUMO

Injection of bacterial endotoxin or granulocyte/macrophage colony-stimulating factor (GM-CSF) into exhypoxic polycythemic mice simultaneously with erythropoietin (EPO) suppressed erythroid cell formation, as monitored by 59Fe incorporation into circulating red blood cells. This effect was dose-dependent and time-dependent. GM-CSF did not inhibit erythroid cell formation directly, as the antibody to the GM-CSF did not neutralize the effect of endotoxin, the inducer of GM-CSF. The suppression of both agents could be partially corrected by prior injection of a monoclonal antibody to tumor necrosis factor alpha (anti-TNF alpha). These results indicate that the suppression of EPO-induced erythroid cell formation by endotoxin and GM-CSF was due in part to the production of TNF alpha.


Assuntos
Endotoxinas/farmacologia , Eritropoese/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Eritrócitos/metabolismo , Eritropoetina/farmacologia , Feminino , Injeções Intravenosas , Ferro/metabolismo , Camundongos , Camundongos Endogâmicos , Proteínas Recombinantes
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