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1.
Indian J Nucl Med ; 32(1): 1-6, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28242974

RESUMO

CONTEXT: PET/CT scan service is one of the capital intensive and revenue-generating centres of a tertiary care hospital. The cost associated with the provisioning of PET services is dependent upon the unit costs of the resources consumed. AIMS: The study aims to determine the cost of providing PET/CT Scan services in a hospital. METHODS AND MATERIAL: This descriptive and observational study was conducted in the Department of Nuclear Medicine at a tertiary apex teaching hospital in New Delhi, India in the year 2014-15. Traditional costing methodology was used for calculating the unit cost of PET/CT scan service. The cost was calculated under two heads that is capital and operating cost. Annualized cost of capital assets was calculated using methodology prescribed by WHO and operating costs was taken on an actual basis. RESULTS: Average number of PET/CT scan performed in a day is 30. The annual cost of providing PET/CT scan services was calculated to be 65,311,719 Indian Rupees (INR) (US$ 1,020,496), while the unit cost of PET scan was calculated to be 9625.92 INR (US$ 150). 3/4th cost was spent on machinery and equipment (75.3%) followed by healthcare personnel (11.37%), electricity (5%), consumables and supplies (4%) engineering maintenance (3.24%), building, furniture and HVAC capital cost (0.76%), and manifold cost (0.05%). Of the total cost, 76% was capital cost while the remaining was operating cost. CONCLUSIONS: Total cost for establishing PET/CT scan facility with cyclotron and chemistry module and PET/CT scan without cyclotron and chemistry module was calculated to be INR 610,873,517 (US$9944899) and 226,745,158 (US$3542893), respectively. (US$ 1=INR 64).

2.
J Perinatol ; 36(8): 681-4, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27054840

RESUMO

OBJECTIVE: Neonatal deaths account for 44% of the world's under-5 child mortality. Over half of all neonatal deaths globally occur in preterm babies. Therefore, improving care of a preterm baby is particularly important to reduce under-5 mortality. The objective of this study was to spell out components of care of preterm/low birth weight babies at first level health facility and at first referral unit (FRU) in low resource settings. STUDY DESIGN: We have analyzed weight-wise survivals at two hospitals attached to medical colleges, J.J. Hospital, Mumbai and General Hospital, Talegaon, and at Rural Hospital, Dahanu. There were three-tier interventions: (i) warmth+ feeding and antibiotics, (ii) improved care at birth plus increased oxygen availability and (iii) use of dopamine. J.J. Hospital went through all these stages one after another; General Hospital had all three going simultaneously. The Rural Hospital had a 1+2. RESULTS: During 1978 to 1984, J.J. Hospital saved 50 to 55% very low birth weight (VLBW) babies by providing warmth, feeding and antibiotics. This percentage increased to 56 to 58%, when adequate oxygen and good care at birth was available (1984 to 1989). For babies in the moderately low birth weight category (MLBW), 1500 to 2000 g at birth, the corresponding figures were 56 to 58% and 84 to 86%. The same interventions led to statistically significant decline in MLBW and VLBW categories at General Hospital, Talegaon (2010 to 2013). The Rural Hospital, Dahanu (1987 to 1992) achieved better survival rates in VLBW (61.5%) and MLBW (92.5%) categories with identical interventions and less staff. CONCLUSION: On the basis of our results, we suggest that in resource-limited settings, the first level health facility may be able to look after short-stay babies that weigh more than 1500 g and that have no respiratory distress. The FRU may look after MLBW babies, with or without respiratory distress, and VLBW babies without respiratory distress by giving special care.


Assuntos
Recém-Nascido de Baixo Peso/crescimento & desenvolvimento , Recém-Nascido Prematuro/crescimento & desenvolvimento , Morte Perinatal/prevenção & controle , Taxa de Sobrevida/tendências , Pré-Escolar , Atenção à Saúde , Países em Desenvolvimento , Feminino , Hospitais/normas , Humanos , Índia , Lactente , Recém-Nascido , Masculino
4.
Oncogenesis ; 2: e72, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-24061575

RESUMO

Estrogen receptor (ER)-ß has been shown to possess a tumor suppressive effect, and is a potential target for cancer therapy. Using gene-expression meta-analysis of human malignant pleural mesothelioma, we identified an ESR2 (ERß coding gene) signature. High ESR2 expression was strongly associated with low succinate dehydrogenase B (SDHB) (which encodes a mitochondrial respiratory chain complex II subunit) expression. We demonstrate that SDHB loss induced ESR2 expression, and that activated ERß, by over-expression or by selective agonist stimulation, negatively affected oxidative phosphorylation compromising mitochondrial complex II and IV activity. This resulted in reduced mitochondrial ATP production, increased glycolysis dependence and impaired cell proliferation. The observed in vitro effects were phenocopied in vivo using a selective ERß agonist in a mesothelioma mouse model. On the whole, our data highlight an unforeseen interaction between ERß-mediated tumor suppression and energy metabolism that may be exploited to improve on the therapy for clinical management of malignant mesothelioma.

5.
J Biol Regul Homeost Agents ; 27(1): 143-54, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23489694

RESUMO

Glioblastoma multiforme (GBM) is among the most devastating human tumors being rapidly fatal despite aggressive surgery, radiation and chemotherapies. It is characterized by extensive dissemination of tumor cells within the brain that hinders complete surgical resection. GBM tumor initiating-cells (TICs) are a rare subpopulation of cells responsible for tumor development, growth, invasiveness and recurrence after chemotherapy. TICs from human GBM can be selected in vitro using the same conditions permissive for the growth of normal neural cells, of which share some features including marker expression, self-renewal capacity, long-term proliferation, and ability to differentiate into neuronal and glial cells. EGFR overexpression and its constitutive activation is one of the most important signaling alteration identified in GBM, and its pharmacological targeting represents an attractive therapeutic goal. We previously demonstrated that human GBM TICs have different sensitivity to the EGFR kinase inhibitors erlotinib and gefitinib, depending on the differential modulation of downstream signaling cascades. In this work we investigated the mechanisms of resistance to erlotinib in two human GBM TIC cultures, analyzing EGF and bFGF individual contribution to proliferation, clonogenicity, and migration. We demonstrated the presence of a small cell subpopulation whose proliferation is supported by EGF and a larger one mainly dependent on bFGF. Thus, insensitivity to EGFR kinase inhibitors as far as TIC proliferation results from a predominant FGFR activation that hides the inhibitory effects induced on EGFR signaling. Conversely, EGF and bFGF induced cell migration with similar efficacy. In addition, unlike neural stem/progenitors cells, the removal of chondroitin sulphate proteoglycans from cell surface was unable to discern EGF- and bFGF-dependent subpopulations in GBM TICs.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/antagonistas & inibidores , Fator 2 de Crescimento de Fibroblastos/farmacologia , Glioblastoma/patologia , Células-Tronco Neoplásicas/patologia , Inibidores de Proteínas Quinases/farmacologia , Idoso , Contagem de Células , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sulfatos de Condroitina/metabolismo , Células Clonais , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/metabolismo , Glioblastoma/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/patologia , Fatores de Tempo , Ensaio Tumoral de Célula-Tronco
6.
Transplant Proc ; 44(9): 2542-4, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23146448

RESUMO

This observational cohort compared 70 consecutive liver transplantations (OLT) with no intra-abdominal drain and 70 control subjects C with an intra-abdominal drain who were operated immediately prior to them. We sought to assess the impact of abdominal drainage on the diagnosis and prevention of early postoperative complications of hemoperitoneum, reinterventions, biliary leaks or percutaneous drainage. We assessed variables related to the recipient (age, indication, pretransplant ascites, body mass index, Model for End-stage Liver Disease score, and rejection episodes, to the donor (age, steatosis and, ischemia time) as well as intra- and postoperative factors (surgery time, blood product use, and coagulopathy). The endpoint was defined as the need for a reintervention, postoperative paracentesis, appearance/drainage of collections, as well as lengths of hospital and intensive care unit (ICU) stays. Postoperative ICU and in-hospital stay were similar between the groups (3.6 versus 3.7 days and 12 versus 14 days respectively). Six patients in the drainage group were reoperated due to hemoperitoneum, whereas it was one in the cohort without drainage. Three patients presented a biliary fistula, two in the group without drainage, and one in the drainage group. One patient in the drainage group required percutaneous drainage of an intra-abdominal collection. The need for postoperative paracentesis was greater among the group without drainage (30% versus 6%; P < .008) and among those with a preoperative ascites > 1000 mL (38%). Patients with drainage displayed a greater incidence of perihepatic hematomas upon ultrasound (50% versus 22%, P < .008) and required more postoperative blood products, especially plasma (P < .01). In conclusion, OLT without intra- abdominal drainage is safe and does not increase morbidity. It seems likely that drainage may be responsible for intra-abdominal hematomas and greater consumption of blood products.


Assuntos
Drenagem , Transplante de Fígado/métodos , Abdome , Adulto , Idoso , Fístula Biliar/etiologia , Fístula Biliar/terapia , Transfusão de Componentes Sanguíneos , Estudos de Casos e Controles , Feminino , Hematoma/etiologia , Hematoma/terapia , Hemoperitônio/etiologia , Hemoperitônio/terapia , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Modelos Lineares , Transplante de Fígado/efeitos adversos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Paracentese , Reoperação , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
7.
Cancer Gene Ther ; 16(10): 786-93, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19363465

RESUMO

In human Burkitt's Lymphoma (BL) BRG cells, a t(8;14) translocation, placing c-myc near the Emu enhancer of the H chain locus, causes tumor expansion. Earlier, we showed that a peptide nucleic acid complementary to the Emu sequence (PNAEmu), specifically inhibited the expression of translocated c-myc and impaired the growth of BRG cells-induced subcutaneous tumors in mice suffering from severe combined immunodeficiency (SCID). In this study, the therapeutic potential of PNAEmu was evaluated in a systemic mouse model. BRG-BL cells transfected with the luciferase gene were inoculated intravenously into SCID mice resulting in a preferential expansion, similar to the one of human adult patients, in the abdominal cavity, central nervous system and bone marrow. The mice were chronically injected intraperitoneally either with PNAEmu or with control PNA. The treatment was stopped when the control animals developed severe neurological symptoms. As detected both by inspection at necropsy and imaging, overall tumor growth in PNAEmu-treated mice decreased by >80%. Histological and immunohistochemical studies showed, only in PNAEmu-treated mice, a substantially reduced BL cell growth at the major sites of invasion and vast areas of necrosis in the lymphomatous tissues, with concomitant c-myc expression downregulation. Altogether, the data support the therapeutic potential of PNAEmu in human adult BL.


Assuntos
Linfoma de Burkitt/tratamento farmacológico , Ácidos Nucleicos Peptídicos/farmacologia , Animais , Linfoma de Burkitt/genética , Linfoma de Burkitt/metabolismo , Linhagem Celular Tumoral , Transformação Celular Viral , Feminino , Humanos , Luciferases de Vaga-Lume/biossíntese , Luciferases de Vaga-Lume/genética , Medições Luminescentes , Camundongos , Camundongos SCID , Proteínas Proto-Oncogênicas c-myc/biossíntese , Proteínas Proto-Oncogênicas c-myc/genética , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Med Genet ; 46(5): 345-51, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19196735

RESUMO

BACKGROUND: Hereditary spastic paraplegia (HSP) with thin corpus callosum (HSP-TCC) is a frequent subtype of complicated HSP clinically characterised by slowly progressive spastic paraparesis with cognitive impairment and thin corpus callosum (TCC). SPG11, the gene associated with the major locus involved, encodes spatacsin, a protein of unknown function. METHODS: Different types of mutations were identified in patients with the complex form of HSP (cHSP) including TCC. We screened a series of 45 index patients with different types of cHSP with (n = 10) and without (n = 35) TCC. RESULTS: Ten mutations, of which five are novel, were detected in seven patients. Of importance, three out of seven mutated patients present with cHSP without TCC. Among the novel mutations identified, we characterised a large intragenic rearrangement deleting 2.6 kb of the SPG11 gene. The rearrangement is due to non-allelic homologous recombination between Alu sequences flanking the breakpoints. CONCLUSIONS: These findings expand the mutation spectrum of SPG11 and suggest that SPG11 mutations may occur more frequently in familial than sporadic forms of cHSP without TCC. This helps to define further clinical and molecular criteria for a correct diagnosis of the SPG11 related form of cHSP. In addition, the intragenic deletion detected here, and the mechanism involved, both provide clues to address the issue of SPG11 missing mutant alleles previously reported.


Assuntos
Agenesia do Corpo Caloso , Mutação Puntual , Proteínas/genética , Deleção de Sequência , Paraplegia Espástica Hereditária/genética , Sequência de Aminoácidos , Sequência de Bases , Análise Mutacional de DNA/métodos , DNA Intergênico/genética , Saúde da Família , Feminino , Frequência do Gene , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Homologia de Sequência de Aminoácidos , Paraplegia Espástica Hereditária/patologia
10.
Gene Ther ; 9(14): 915-21, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12085239

RESUMO

Intravenous infusion of bone marrow stromal cells (BMSCs) has been proposed as a means to support hematopoiesis in bone marrow transplantation or as a vehicle for gene therapy. However, it seems that this route of injection leads to engraftment of a small proportion of BMSCs, possibly because they are unable to cross the endothelial barrier. We have transplanted human BMSCs, ex vivo expanded and transduced with a retrovirus encoding the human erythropoietin gene, either intravenously or subcutaneously with or without a tridimensional scaffold in non-conditioned NOD/SCID mice. Efficiency of engraftment was evaluated monitoring the hematocrit levels. Systemic infusion never significantly increased hematocrit levels, whereas subcutaneous transplantation of the same number of cells induced an important increase of the hematocrit (approximately 70%) for at least 2 months. A substantial increase in the length of the response was observed when cells were subcutaneously transplanted in a tridimensional scaffold. To determine whether the transient effect was due to cell loss or to reduction in expression, the cells implanted into a tridimensional scaffold were recovered, expanded in vitro, and re-implanted in a new group of mice. Again the hematocrit levels rose 2 weeks after transplantation ( approximately 70%). These results demonstrate that ex vivo expanded human BMSCs are not quantitatively transplantable by systemic infusion in non-conditioned recipients, whereas the local implantation into a tridimensional scaffold allows long-term engraftment and efficient expression of a foreign gene.


Assuntos
Transplante de Medula Óssea/métodos , Eritropoetina/genética , Terapia Genética/métodos , Células Estromais/transplante , Transdução Genética/métodos , Adipócitos , Animais , Osso e Ossos/citologia , Diferenciação Celular , Condrócitos , Feminino , Vetores Genéticos/administração & dosagem , Infusões Intravenosas , Injeções Subcutâneas , Camundongos , Camundongos SCID , Retroviridae/genética , Células Estromais/citologia , Células Estromais/metabolismo , Transplante Homólogo
11.
Mech Dev ; 109(2): 323-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11731244

RESUMO

Emx2 is a vertebrate homeobox gene involved in the control of the central nervous system development. In the formation of cerebral cortex, Emx2 expression is restricted mainly to the germinal ventricular zone fading away in the first postmitotic neurons. This expression pattern, the severe impairment of cortex organization and the size in mutant mice suggest a role of Emx2 in the control of proliferation and migration of neural precursor cells. The observed persistence of Emx2 expression in adult neurogenic areas in vivo is here confirmed at later stages. We also find that Emx2 is expressed at high levels in adult neural stem cells (ANSCs) in vitro and is down modulated upon differentiation. Overexpression of Emx2 gene in ANSCs has an anti-proliferative effect but it does not influence a particular differentiation pathway. Our results suggest that Emx2 may act promoting an asymmetric mode of cell division thereby increasing the size of a transit amplifying population.


Assuntos
Sistema Nervoso Central/citologia , Proteínas de Homeodomínio/biossíntese , Neurônios/citologia , Animais , Encéfalo/metabolismo , Bromodesoxiuridina/metabolismo , Diferenciação Celular , Divisão Celular , Separação Celular , Células Cultivadas , Clonagem Molecular , Citometria de Fluxo , Vetores Genéticos , Hipocampo/metabolismo , Imuno-Histoquímica , Camundongos , Microscopia de Fluorescência , Retroviridae/genética , Timidina/metabolismo , Fatores de Tempo , Fatores de Transcrição
12.
Eur J Immunol ; 31(3): 743-51, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11241278

RESUMO

Internucleosomal DNA fragmentation following the activation of endonucleases is the common end point of apoptosis. DNase I, a Ca(2+) / Mg(2+)-dependent endonuclease ubiquitously expressed in mammalian tissues, is believed to play a role in this process. To analyze the in vivo function of this enzyme in human cells, we have generated a cell line with targeted disruption of the DNase I gene, as well as several stable cell lines which overexpress the DNase I gene. Inactivation of the human DNase I gene was obtained in the Jurkat T cell clone JA3, characterized by high susceptibility to apoptotic cell death induced by pharmacological stimuli. JA3 cells, after disruption of the DNase I gene, became resistant to apoptotic stimuli. DNase I was overexpressed in the human cell lines JA3, K562 (erythroleukemia), M 14 (melanoma) and CEM (T cell lymphoma). Remarkably, stable overexpression of DNase I gene resulted in accelerated apoptosis in JA3 cells and induced apoptosis in K562, CEM and M14 cell lines, which are otherwise resistant to internucleosomal DNA degradation following pharmacological stimuli. Our study provides the first in vivo evidence that DNase I mediates internucleosomal DNA degradation in human cells undergoing drug-induced apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , DNA/metabolismo , Desoxirribonuclease I/fisiologia , Nucleossomos/metabolismo , Núcleo Celular/ultraestrutura , Sobrevivência Celular/efeitos dos fármacos , Cicloeximida/farmacologia , Fragmentação do DNA/efeitos dos fármacos , Dactinomicina/farmacologia , Desoxirribonuclease I/genética , Etoposídeo/farmacologia , Marcação de Genes , Humanos , Células Jurkat , Cinética , Paclitaxel/farmacologia , Transfecção , Células Tumorais Cultivadas , Receptor fas/metabolismo
13.
Wound Repair Regen ; 9(6): 460-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11896988

RESUMO

Adult stem cells are self-renewing, pluripotent, and able to repopulate the tissue in which they reside. Cells endowed with these properties have been isolated from several tissues and an increasing number of reports provide evidence of their ability, following transplantation, to engraft host tissues other than those of their origin. In this setting, interest in the well-documented capacity of bone marrow stromal cells to undergo multilineage differentiation is growing. Neural and cardiomyogenic lineages have recently been proposed as additional differentiative pathways of these cells. However, culture conditions and inductive molecules can alter the behavior of bone marrow stromal cells and the microenvironment is critical for proper in vivo delivery. The maintenance of their stem properties and the possibility of reprogramming their commitment is a field of primary interest given the potential use of these cells in regenerative medicine. We discuss here how the microenvironmental cues, and the growth factors that physiologically govern commitment and subsequent differentiation, influence the properties of bone marrow stromal cells and modulate their engraftment into host tissues.


Assuntos
Células da Medula Óssea/fisiologia , Mesoderma/fisiologia , Células-Tronco/fisiologia , Transplante de Medula Óssea , Diferenciação Celular , Humanos , Regeneração/fisiologia , Células Estromais/fisiologia , Cicatrização/fisiologia
15.
Indian J Pediatr ; 67(7): 483-5, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10957831

RESUMO

A cross-sectional study of preschool children from 450 families from a residential colony of 'D' class hospital employees was undertaken to study food security & associated variables. Food security was established from (a) 24 hours recall method with 1 day weighment and (b) monthly food purchase inventory for cereals and pulses. Relationship between food secure status and variables of interest was studied from Chi-square value and odds ratio. Only 42.6% households and 54% preschool children from these households were calorically secure. Insecurity was the highest in 48-59 months age group. Per capital income, increasing birth order, family size, household size, less years of schooling of the mother, less than 4 meals per day and pulse insufficiency at home were associated with food insecurity. Per capita income ensures food availability at home. Family size and household size probably ensure distribution. Mother's education, frequent feeds more than four, ensure that it reaches the preschool children.


Assuntos
Ingestão de Energia , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Fatores Socioeconômicos
17.
Exp Hematol ; 28(5): 569-74, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10812247

RESUMO

OBJECTIVE: +HOX genes are expressed in the hematopoietic system and increasing data point to their involvement in the control of proliferation and/or differentiation. Genes belonging to the C cluster are preferentially expressed in developing and differentiated lymphoid lineages. However, recent studies demonstrated, by RT-PCR, that the HOXC4 gene is also actively transcribed in the most undifferentiated hematopoietic cells (CD34(+)38(low)) and in more mature myeloid and erythroid progenitors. We evaluated the expression of HOXC4 protein on human CD34(+) cells and the in vitro effect of its overexpression on proliferation and differentiation. MATERIALS AND METHODS: We assessed the expression of HOXC4 on human CD34(+) cells using a polyclonal antibody raised against the C-terminal portion of the protein expressed using the baculovirus system. Overexpression of HOXC4 in human CD34(+) cells was obtained by retroviral gene transfer; its effect on clonogenic (CFU-GM, BFU-E, and CFU-GEMM) and early progenitors (LTC-IC) was evaluated. RESULTS: The HOXC4 protein is indeed expressed in human CD34(+) cells, and its overexpression in human CD34(+) cells increases the proliferation potential of clonogenic and early progenitors. CFU-GM showed a median threefold expansion (range: 1.1-19.4; p < 0.002) compared with control transduced with the vector alone. The increment of BFU-E was higher (median ninefold, range 2.5-35; p < 0. 0009) and erythroid colonies presented a larger size with normal morphology. An even more marked effect was observed on LTC-IC (median 13, onefold; range 4.1-102.1, p < 0.0001). CONCLUSION: We demonstrate that HOXC4 is expressed in CD34(+) cells and that its overexpression induces an in vitro expansion of committed as well as very early hematopoietic progenitors. The most striking effect was obtained on LTC-IC with an expansion of 13.1-fold. The enforced expression of HOXC4 induced a significant increase (p < 0.009) in the number of erythroid colonies compared with CFU-GM, although without perturbing, at least in vitro, the maturation program of the cells. On the other hand, the effect of the gene overexpression did not induce any skewing in the colony types derived from the myeloid lineage.


Assuntos
Células-Tronco Hematopoéticas/citologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Antígenos CD34/análise , Diferenciação Celular , Divisão Celular , Linhagem Celular , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Vetores Genéticos , Células-Tronco Hematopoéticas/fisiologia , Humanos , Proteínas Recombinantes/biossíntese , Retroviridae , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
18.
FASEB J ; 14(5): 680-90, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10744625

RESUMO

Cyclic ADP-ribose (cADPR) is a universal second messenger that regulates many calcium-related cellular events by releasing calcium from intracellular stores. Since these events include enhanced cell proliferation and since the bone marrow harbors both ectoenzymes that generate cADPR from NAD(+) (CD38 and BST-1), we investigated the effects of extracellular cADPR on human hemopoietic progenitors (HP). Exposure of HP to 100 microM cADPR for 24 h induced a significant increase in colony output (P<0.01) and colony size (P<0.003). A horizontal expansion of HP, as demonstrated by a markedly increased replating efficiency in semisolid medium (up to 700 times compared to controls), was also observed, indicating that cADPR priming can affect cell growth for multiple generations over several weeks after exposure. Influx of extracellular cADPR into the cells was demonstrated, and a causal relationship between the functional effects and the increase of intracellular free calcium concentration induced by cADPR on HP was established through the use of specific antagonists. Similar effects on HP were produced by nanomolar concentrations of the nonhydrolyzable cADPR analog 3-deaza-cADPR. These data demonstrate that extracellular cADPR behaves as a cytokine enhancing the proliferation of human HP, a finding that may have biomedical applications for the ex vivo expansion of hemopoietic cells.


Assuntos
Adenosina Difosfato Ribose/análogos & derivados , Cálcio/metabolismo , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Adenosina Difosfato Ribose/antagonistas & inibidores , Adenosina Difosfato Ribose/metabolismo , Adenosina Difosfato Ribose/farmacologia , Antígenos CD34/metabolismo , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , ADP-Ribose Cíclica , Citarabina/farmacologia , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , Humanos , Líquido Intracelular/metabolismo , Sistemas do Segundo Mensageiro
19.
Trop Doct ; 29(4): 242-3, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10578643

RESUMO

Oxygen saturations were compared, 10 min before and 10, 20 and 30 min after orogastric and nasogastric feeds, in 10 stable newborns. The mean saturations were significantly lower with mere passage of nasogastric tube and continued to be so during feeds. There was no difficulty in securing the orogastric tube and no baby aspirated milk.


Assuntos
Nutrição Enteral/métodos , Recém-Nascido Prematuro , Intubação Gastrointestinal/métodos , Humanos , Recém-Nascido , Oxigênio/sangue
20.
Development ; 125(18): 3681-7, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9716533

RESUMO

In the developing Drosophila eye, individual cell fates are specified when general signaling mechanisms are interpreted in the context of cell-specific transcription factors. Lozenge, a Runt/AML1/CBFA1-like transcription factor, determines the fates of a number of neuronal and non-neuronal cells by regulating the expression of multiple fate-determining transcription factors. The Lozenge protein is expressed in the nuclei of the cells that it patterns and also in their undifferentiated precursors. An enhancer element located within the second intron of the lozenge gene is responsible for its eye-specific expression. Lozenge is not itself a cell-specific transcription factor, rather it prepatterns the eye disc by positioning cell-specific factors in their appropriate locations.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Proteínas de Drosophila , Drosophila/crescimento & desenvolvimento , Olho/crescimento & desenvolvimento , Células-Tronco/metabolismo , Fatores de Transcrição/fisiologia , Animais , Padronização Corporal/genética , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica no Desenvolvimento , Íntrons , Transdução de Sinais/fisiologia , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética
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