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1.
Colorectal Dis ; 10(5): 498-502, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17949445

RESUMO

BACKGROUND: The role of palliative surgical resection in patients presenting with locally advanced or metastatic colorectal cancer (CRC) is unclear. Resection is often limited to symptomatic management of bleeding, obstruction, perforation or for relief of pain, in patients with an adequate performance status and an expected life span of over several weeks. An exploratory analysis to evaluate the influence of a palliative surgical resection on survival outcome in patients with advanced CRC is reported. METHOD: A retrospective review of medical records of all patients diagnosed with advanced CRC at our institution between the years 1998 and 2003 was undertaken. Tumour registry data were reviewed to identify age, gender, modalities of therapy [i.e. surgery (S), chemotherapy (C), radiation] and overall survival. IRB approval was obtained for this study. RESULTS: One hundred and eighty-five patients were identified. Median age was 67 years (range 30-99). M:F ratio was 1:1. Sixty-two per cent of patients (115/185) underwent a palliative surgical intervention. Median survival of patients who underwent S and those that did not undergo S was 22 and 3 months respectively (P < 0.0001). Forty-eight per cent of patients (79/184) underwent systemic C. Median survival of patients who received C + S, and patients who received C alone was 30 and 15 months respectively (P < 0.0004). Fifty-one per cent of patients who underwent S, received C; 30% of patients who did not undergo S, received C. Chemotherapy data were available on 46 of 79 patients. Patients treated with S + C, and C without S, received a median of 9 and 6 months of therapy respectively. The median number of regimens used were similar in both. CONCLUSION: These exploratory data suggest a positive influence of a palliative resection performed during the disease course of patients with advanced CRC. The increased frequency of utilization and the more prolonged duration of C in the surgically treated patients may in part contribute to this improved survival. This may also be reflective of performance status at the time of diagnosis. Future trials enrolling patients with advanced CRC should prospectively stratify for surgical intervention to further clarify the influence of this modality on the outcome of systemic therapy in this disease.


Assuntos
Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/tratamento farmacológico , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Cuidados Paliativos , Estudos Retrospectivos , Taxa de Sobrevida
2.
J Assoc Physicians India ; 55: 587-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18019802

RESUMO

Rosai Dorfman disease (RDD) or sinus histiocytosis with massive lymphadenopathy (SHML) is a rare disorder that typically manifests as lymphadenopathy and systemic symptoms. The authors report a 45 year old lady who presented with nasal mass and generalised lymphadenopathy. Histopathological examination demonstrated lymphophagocytosis (emperipolesis) consistent with a diagnosis of RDD. The clinical and histologic aspects of the disease are discussed as a rare cause of generalised lymphadenopathy.


Assuntos
Histiocitose Sinusal/patologia , Doenças Linfáticas/patologia , Feminino , Histiocitose Sinusal/diagnóstico , Histiocitose Sinusal/imunologia , Humanos , Doenças Linfáticas/diagnóstico , Pessoa de Meia-Idade
4.
Am J Hematol ; 66(2): 151-2, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11421298

RESUMO

Intravenous gammaglobulins are used for the treatment of various auto-immune hematological disorders. Renal failure is a relatively rare, but an increasingly recognized side effect of gammaglobulin therapy. Although the renal failure is usually reversible, renal replacement therapy is required occasionally. A high index of suspicion, early recognition and appropriate intervention can prevent this complication. We herewith describe two patients with an immune hematological disorder, who developed acute renal failure after treatment with intravenous gammaglobulins. A brief review of the possible risk factors, pathophysiology and management of this complication is provided.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Imunoglobulinas Intravenosas/efeitos adversos , Injúria Renal Aguda/etiologia , Idoso , Idoso de 80 Anos ou mais , Anemia Hemolítica Autoimune/complicações , Anemia Hemolítica Autoimune/tratamento farmacológico , Feminino , Humanos , Masculino , Púrpura Trombocitopênica Idiopática/complicações , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Fatores de Risco , gama-Globulinas/administração & dosagem , gama-Globulinas/efeitos adversos
5.
Biochemistry ; 39(32): 9679-86, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10933784

RESUMO

Synaptotagmin II (Syt II) is a key protein in the calcium-dependent exocytosis of synaptic vesicles. It contains two domains homologous to the C2 regulatory region of protein kinase C. The C2A domain acts as a calcium sensor, while the C2B domain has high affinity for inositol polyphosphates (InsP(n)()s) and phosphoinositide polyphosphates (PtdInsP(n)()s). We describe the use of a surface plasmon resonance biosensor in determining the binding kinetics of the C2B domain with InsP(n)() and PtdInsP(n) ligands. Biosensor surfaces were prepared with covalently attached Ins(1,4,5)P(3), Ins(1,3,4,5)P(4), and InsP(6) ligands. The interactions of bacterially expressed His(6)-tagged C2B and (C2A+C2B) domains of Syt II were examined in the presence and absence of competing InsP(n)s and PtdInsP(n)s. Both His(6)-C2B and His(6)-(C2A+C2B) exhibited the highest affinity for the Ins(1,3,4,5)P(4)-modified surface with a K(D) value of 6 nM. The His(6)-(C2A+C2B) had a 10-fold lower association rate constant for the InsP(6)-linked surface (k(a) = 4.6 x 10(3) M(-1) s(-1)) than for the Ins(1,3,4,5)P(4)-modified surface (k(a) = 6.8 x 10(4) M(-1) s(-1)). Two water-soluble phosphoinositides, dioctanoyl-PtdIns(3,4,5)P(3) and dioctanoyl-PtdIns(4,5)P(2), were superior to the soluble InsP(n)s in displacing binding to the Ins(1,3,4,5)P(4)-modified surface. The binding of His(6)-C2B and His(6)-(C2A+C2B) to InsP(n) surfaces did not show significant calcium dependence. These data support a model in which the binding of the C2B domain of Syt II to PtdInsP(n)s is important for the docking and/or fusion of the secretory vesicles to the synaptic plasma membrane.


Assuntos
Fosfatos de Inositol/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Fosfatidilinositóis/metabolismo , Ligação Competitiva , Técnicas Biossensoriais , Cálcio/farmacologia , Inositol 1,4,5-Trifosfato/metabolismo , Cinética , Ligantes , Modelos Teóricos , Ácido Fítico/metabolismo , Estrutura Terciária de Proteína , Sinaptotagmina II
6.
Am J Med Sci ; 319(3): 131-7, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10746822

RESUMO

BACKGROUND: Cardiovascular disease rates are improving in the United States, but not for certain subgroups, especially some African Americans. The objective of the study is to assess current levels and trends in cardiovascular disease mortality in Mississippi. METHODS: Mortality statistics from the U.S. vital statistics system for the period 1979-95 were used. Comparison of age-adjusted mortality rates in Mississippi with the other states for the year 1995 and with the nation as a whole over the period of 1979-95 was performed. RESULTS: Mississippians had the highest age-adjusted cardiovascular disease morality rates in the nation in 1995. Overall, the cardiovascular rates in Mississippi were 37% higher than for the U.S. African American men and women from Mississippi had especially high cardiovascular mortality rates, approximately 50% and 70% higher than their white counterparts, respectively. The higher burden of cardiovascular disease in African Americans from Mississippi was especially marked in the younger age groups. Since about 1984-85, cardiovascular mortality rates in Mississippi have been increasing for African Americans, whereas nationally they have been decreasing. In contrast, cardiovascular mortality rates for whites in Mississippi have been declining, but at a much slower rate than seen nationally. The wide divergence in trends for African American and white men and women over that period in Mississippi has lead to an estimated 19,400 excess cardiovascular deaths. Virtually identical trends were found for heart disease. CONCLUSIONS: Cardiovascular diseases are a major public health problem in Mississippi that is especially severe in African American residents, and the problem is growing worse each year. It is important to identify the determinants of and solutions for this enormous public health problem in Mississippi.


Assuntos
Doenças Cardiovasculares/mortalidade , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mississippi/epidemiologia , Mortalidade/tendências , Distribuição por Sexo , População Branca/estatística & dados numéricos
7.
J Leukoc Biol ; 66(6): 930-6, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10614774

RESUMO

Clinical reports indicate that acute ethanol intoxication in chronic ethanol abusers is associated with neutropenia. We hypothesize that ethanol accelerates the apoptosis of neutrophils thus decreasing the peripheral blood count of neutrophils. We studied the effect of ethanol on neutrophil apoptosis in vivo as well as in vitro. Human neutrophils harvested from healthy subjects after an alcohol drinking binge showed enhanced apoptosis (before, 0.5+/-0.25 vs. after, 26.1+/-2.6% apoptotic neutrophils/field). Peritoneal neutrophils isolated from ethanol-treated rats also showed increased (P < 0.0001) apoptosis when compared with neutrophils isolated from control rats (control, 0.8+/-0.2% vs. ethanol, 11.8+/-0.7% apoptotic neutrophils/field). In in vitro studies, ethanol in concentrations of 50 mM and higher accelerated the apoptosis of human and rat neutrophils. This effect of ethanol on human neutrophils was time dependent. DNA isolated from ethanol-treated human neutrophils displayed integer multiples of 180 base pairs (ladder pattern), further confirming the effect of ethanol on neutrophil apoptosis. N(G)-monomethyl-L-arginine monoacetate and N(G)-nitro-L-arginine methyl ester, inhibitors of nitric oxide (NO) synthase, attenuated the ethanol-induced neutrophil apoptosis. Sodium nitroprusside, a NO donor, also promoted neutrophil apoptosis. Moreover, ethanol enhanced neutrophil expression of inducible NO synthase. In addition, ethanol stimulated neutrophil NO generation. These results suggest that ethanol accelerates neutrophil apoptosis. This effect of ethanol on neutrophil apoptosis seems to be mediated through the generation of NO.


Assuntos
Apoptose/efeitos dos fármacos , Etanol/toxicidade , Neutrófilos/efeitos dos fármacos , Óxido Nítrico/fisiologia , Animais , Apoptose/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Humanos , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/enzimologia , Macrófagos Peritoneais/metabolismo , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Neutrófilos/citologia , Neutrófilos/enzimologia , Neutrófilos/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase/sangue , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Cavidade Peritoneal/citologia , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie , ômega-N-Metilarginina/farmacologia
8.
Protist ; 149(2): 135-46, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-23196163

RESUMO

Knowledge of secondary structure, formed by the gene spacer regions of the primary transcript of nuclear rDNA cistrons, is lacking for most phyla of eukaryotes. We have sequenced the first internal transcribed spacer region (ITS-1) of multiple representatives of the Volvocales, and from comparisons of these, derived a secondary structure common to the entire group. The secondary structure model is supported by numerous compensating base pair changes located within the paired regions of the stem-loops. Within the morphological species, such as those of Astrephomene and Gonium, the three basal nucleotide pairs of helices are highly conserved in primary sequence, and the single stranded region rich in CCAA is identical in sequence, even when isolates come from all continents of the earth. In other Volvocacean species known to include many pairs of mating types, this same level of conservation is found to correlate with the mating subgroups of the species. Thus a comparable degree of sequence similarity appears to characterize all isolates of a "biological" species; this is valid for taxonomic species only where the biological and taxonomic species levels coincide. In addition, the ITS-1 contains information useful for population analyses, and spacer secondary structure may have additional phylogenetic utility at the level of class or subclass when that information becomes available for other protistan groups.

10.
Biochemistry ; 36(13): 3941-9, 1997 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9092824

RESUMO

Nucleolar phosphoprotein B23 is a putative ribosome assembly factor with a relatively high affinity for peptides containing sequences of nuclear localization signals (NLSs) of the SV40 T-antigen type [Szebeni, A., Herrera, J. E., & Olson, O. J. (1995) Biochemistry 34, 8037-8042]. The effects of protein B23 on nuclear import were determined by an in vitro assay [Dean, D. A., & Kasamatsu, H. (1994) J. Biol. Chem. 269, 4910-4916] using NLS peptide-conjugated bovine serum albumin (NLS-BSA) or the HIV-1 Rev protein as substrates for import into isolated rat liver nuclei. The import was ATP-dependent and inhibited by wheat germ agglutinin or by an antibody against p97, a component of the nuclear import system. The rate of import of either substrate was increased if protein B23 was added to the incubation medium. Similar enhancements of import were seen with both isoforms (B23.1 and B23.2). The stimulatory effect on Rev protein import was saturable with maximum stimulation (2-3-fold) at a molar ratio of protein B23:Rev of approximately 1:1. Phosphorylation of protein B23.1 by casein kinase II produced an additional doubling of the import rate. This effect was not seen if protein B23.1 was phosphorylated with a cdc2 type protein kinase. Mutant forms of protein B23.1 in which the nuclear localization signal was either deleted or altered did not stimulate import of the substrates. These results suggest that protein B23 plays a role as an accessory factor in the nuclear import of the NLS-containing proteins and that phosphorylation at sites in the highly acidic segments of the protein enhances the stimulatory effect.


Assuntos
Núcleo Celular/metabolismo , Produtos do Gene rev/metabolismo , HIV-1 , Proteínas Nucleares/metabolismo , Albumina Sérica/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Anticorpos Monoclonais/imunologia , Antígenos Transformantes de Poliomavirus/metabolismo , Caseína Quinase II , Reagentes de Ligações Cruzadas/metabolismo , Fluoresceínas , Corantes Fluorescentes/metabolismo , Fígado/metabolismo , Microscopia de Fluorescência , Mutação , Sinais de Localização Nuclear , Proteínas Nucleares/química , Proteínas Nucleares/genética , Proteínas Nucleares/imunologia , Proteínas Nucleares/farmacologia , Nucleofosmina , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Aglutininas do Germe de Trigo/farmacologia , Produtos do Gene rev do Vírus da Imunodeficiência Humana
11.
J Biol Chem ; 272(7): 4237-44, 1997 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-9020139

RESUMO

Synaptotagmin (Syt) II, a synaptic vesicle protein containing two copies of highly conserved protein kinase C homology regions known as the C2A and C2B domains, acts as a Ca2+ sensor and provides both phospholipid and inositol polyphosphate (IPn) recognition domains important in endo- and exocytosis. Four photoaffinity analogues of IP3, IP4, and IP6 containing a P-1- or P-2-linked 4-benzoyldihydrocinnamidyl (BZDC) photophore were used to label glutathione S-transferase (GST) fusion constructs of the Syt II-C2A and C2B domains. The P-2-linked [3H]BZDC-IP6 showed efficient, IP6-displaceable labeling of the GST-Syt II-C2B. The rank order of photocovalent modification paralleled the order of competitive displacement: IP6 (P-2-linked) > IP4 > IP3. The P-1-linked [3H]BZDC-IP6 failed to label the C2B domains. The GST-Syt III-C2B domain, which lacks IP6 binding affinity, also failed to undergo labeling by P-2-linked [3H]BZDC-IP6. When mixtures of the 32-amino acid basic peptide corresponding to the essential IPn binding region of the Syt II-C2B domain and GST-Syt II-C2B were labeled by a stoichiometric amount of P-2-linked [3H]BZDC-IP6, the two polypeptides showed equivalent affinity for the photolabel. Although the CD spectrum of this 32-mer at two pH values showed a random coil, the photoaffinity analogue of IP6 appeared to induce a binding-compatible structure in the short peptide.


Assuntos
Fosfatos de Inositol/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Marcadores de Afinidade , Sequência de Aminoácidos , Animais , Benzofenonas/química , Ligação Competitiva , Fosfatos de Inositol/química , Cinética , Camundongos , Dados de Sequência Molecular , Peptídeos/metabolismo , Fotólise , Ligação Proteica , Sinaptotagmina II , Trítio
12.
Diabetes Care ; 19(7): 771-4, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8799638

RESUMO

OBJECTIVE: A study was conducted to determine the influence of sample temperature on manual reflectance photometers, automatic reflectance photometers, and electrochemical glucometers. RESEARCH DESIGN AND METHODS: Aqueous and blood-based control solutions were tested at temperatures ranging from 25 to 44 degrees C. With the Accu-Chek 3, One Touch, and Satellite G glucometers, multiple glucose determinations were performed on each sample. RESULTS: The results indicate that the manual reflectance photometry glucometer is prominently influenced by variation in sample temperature. The effect of sample temperature is greatest at high glucose levels. CONCLUSIONS: Caution may be required in the interpretation of manual reflectance photometry glucometer measurements in febrile or hypothermic diabetic patients.


Assuntos
Glicemia/análise , Eletroquímica/métodos , Fotometria/métodos , Temperatura , Humanos , Fitas Reagentes , Reprodutibilidade dos Testes
13.
Indian J Exp Biol ; 34(5): 444-67, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-9063078

RESUMO

Alcoholics extracts of 266 botanically identified plant materials from 222 plant species have been tested for various biological activities including chemotherapeutic and pharmacological screenings. Biological activities have been observed in 89 extracts. Follow-up studies have been carried out in some plants with confirmed activity. The active principles and results of these studies are reported.


Assuntos
Plantas Medicinais/química , Animais , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos , Feminino , Índia , Masculino , Extratos Vegetais/farmacologia , Gravidez
14.
J Ethnopharmacol ; 51(1-3): 161-5, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9213611

RESUMO

Forests are the chief resource for the collection and exploration of biological materials. The past few decades have witnessed a large scale deforestation in India due to substantial pressures generated by population growth, leading to demand for more land for agriculture, urbanization and industrial activities, in addition to increased demand for fuel wood and timber. This has resulted in the loss of soil cover, habitat destruction, environmental degradation and ecological imbalance. This scenario has created a progressive awareness for the conservation and restoration of habitats and, thus, the declaration of many forest areas into protected zones, such as national parks, biosphere reserves, etc., including the protection of some marine areas, by both the National and State Governments. Normally, permission for biological collecting is not granted in these protected areas. In India, forests are a State subject and grant for collection permission is vested with the State Forest Departments. In the absence of any rules, regulations and guidelines, either from National or State Governments, forest authorities impose their terms and conditions, which are arbitrary and even contradictory at times, in the process of granting collecting permits. A set of new rules to be applied throughout the country is needed.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Ecossistema , Expedições/legislação & jurisprudência , Licenciamento/legislação & jurisprudência , Farmacognosia/legislação & jurisprudência , Manejo de Espécimes , Comércio/legislação & jurisprudência , Países em Desenvolvimento , Ecologia , Economia , Agricultura Florestal/legislação & jurisprudência , Órgãos Governamentais , Índia , Política Pública
15.
Kidney Int ; 48(5): 1508-16, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8544408

RESUMO

We have previously shown that heparin given subcutaneously on a daily basis lowers blood pressure in hypertensive rat models, and that this blood pressure lowering effect is endothelium-dependent. The present study describes the effects of heparin on endothelial cell (EC) apical surface structures and cytoskeletal elements, namely, actin and vimentin as well as EC proliferative activity. The EC line (CRL 1998) was cultured, treated with different concentrations of heparin (0, 50, 100, 500 U/ml) for 4, 24 or 48 hours, and fixed for scanning electron microscopy (SEM), and immunofluorescence microscopy (IFM) studies. Enzyme-linked immunosorbent assays (ELISA) and flow cytometric analysis were performed on EC monolayers treated with different concentrations of heparin for quantitative detection of actin and vimentin. By SEM study the cell surface showed generalized smoothing as a result of blunting of surface microvilli with increasing time of exposure and dosage of heparin. By IFM study, the detectable actin signal within ECs became progressively reduced in both its cellular distribution and the apparent number of cells that remained reactive. By 48 hr/500 U heparin, the actin signal was almost undetectable. Vimentin showed a moderate reduction in the cellular distribution of labeling. Quantitatively, actin was significantly reduced after the 24 hour treatment with a higher dose of heparin (500 U/ml), from a baseline optical density (OD) of 1.12 +/- 0.060 to 0.866 +/- 0.008 (P < 0.0027). After 48 hours of treatment at both 100 U/ml and 500 U/ml heparin, actin was significantly reduced from a baseline OD of 1.347 +/- 0.063 to 1.090 +/- 0.039 (P < 0.0039) and 0.844 +/- 0.074 (P < 0.008), respectively. However, vimentin was significantly reduced only after 48 hours of treatment with a high dose of heparin (500 U/ml), from baseline OD 1.82 +/- 0.052 to 1.41 +/- 0.004 (P < 0.002). The flow cytometric findings were virtually identical to the ELISA data for actin and vimentin. These qualitative and quantitative changes in actin and vimentin are consistent with apparent smoothing and relaxation of the EC's apical surface. Labeling with the cell cycle marker MIB-1 (monoclonal antibody Ki-67), showed a progressive reduction in the observed intensity in heparin treated cells with substantially fewer cells being positive. After a 48 hour treatment with heparin (500 U/ml), most ECs displayed only dim labeling of the nucleolus. This finding is consistent with an antiproliferative effect. Overall, these findings are additive to our previous observations, and demonstrate that heparin causes EC cytoskeletal reorganization which is a potential mechanism for vascular relaxation.


Assuntos
Citoesqueleto/efeitos dos fármacos , Citoesqueleto/ultraestrutura , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/ultraestrutura , Heparina/farmacologia , Vasodilatação/fisiologia , Citoesqueleto/fisiologia , Endotélio Vascular/fisiologia , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Imunofluorescência , Microscopia Eletrônica de Varredura
16.
Blood ; 86(3): 1139-47, 1995 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-7542497

RESUMO

Leukemia may be viewed as a clonal expansion of blast cells; however, the role of primitive cells and/or stem cells in disease etiology and progression is unclear. We investigated stem cell involvement in leukemia using fluorescence in situ hybridization (FISH), immunofluorescence labeling of hematopoietic subpopulations, and flow cytometric analysis/sorting to discriminate and quantify cytogenetically aberrant stem cells in 12 acute myeloid leukemia (AML) and three myelodysplastic (MDS) specimens. Flow cytometric analysis and sorting were used to discriminate and collect a primitive subpopulation enriched in stem cells expressing CD34+ and lacking CD33 and CD38 (CD34+lin-). A subpopulation containing progenitors and differentiating myeloid cells expressed CD34, CD33, and CD38 (CD34+lin+). Nine specimens contained less than 10% CD34+ cells and, thus, were considered to be CD34- leukemias. Mature lymphoid, myeloid, and erythroid subpopulations were sorted on the basis of antigen-linked immunofluorescence. Cytogenetically aberrant cells in sorted subpopulations were identified using FISH with enumerator probes selected on the basis of diagnosis karyotype. Cytogenetically aberrant CD34+lin- cells were present at frequencies between 9% and 99% in all specimens. CD34+lin- cytogenetically aberrant cells comprised between 0.05% and 11.9% of the marrow/blood specimens. Cytogenetically aberrant CD34+lin+ cells constituted 0.01% tp 56% of the marrow/blood population. These data demonstrate that aberrant cells are present in primitive CD34+ stem cell compartments, even in CD34- leukemias. Stem cell involvement was confirmed further by sorting lymphoid and erythroid subpopulations from eight specimens in which the predominant leukemic population lacked lymphoid/erythroid differentiation markers. In these specimens, as well as in multiple lineages, suggests involvement of a cell(s) with multilineage capabilities. The ability of aberrant CD34+lin- stem cells to contribute to clonal and compartment expansion within immunofluorescently defined subpopulations was evaluated to explore the functional phenotype of aberrant CD34+lin- cells. Analysis of compartment size and aberrant cell frequency suggests that frequency of cytogenetically aberrant stem cells is uncoupled from compartment size. These data suggest that cytogenetically aberrant cells in the primitive compartment show varying abilities to expand primitive compartments. Cytogenetically aberrant CD34+lin- cells precede the blast subpopulation in hierarchical maturation and may in some cases by considered preleukemic, requiring maturation or additional mutations before transformation (eg, compartmental expansion) occurs.


Assuntos
Aberrações Cromossômicas/patologia , Leucemia Mieloide/patologia , Síndromes Mielodisplásicas/patologia , Células-Tronco Neoplásicas/patologia , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Doença Aguda , Adulto , Idoso , Antígenos CD/análise , Antígenos CD34 , Antígenos de Diferenciação/análise , Antígenos de Diferenciação Mielomonocítica/análise , Transtornos Cromossômicos , Feminino , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Masculino , Glicoproteínas de Membrana , Pessoa de Meia-Idade , N-Glicosil Hidrolases/análise , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico
17.
Plant Cell ; 5(11): 1661-1668, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12271050

RESUMO

Relative quantities of DNA in individual nuclei of stem and leaf epidermal cells of Arabidopsis were measured microspectrofluorometrically using epidermal peels. The relative ploidy level in each nucleus was assessed by comparison to root tip mitotic nuclei. A clear pattern of regular endopolyploidy is evident in epidermal cells. Guard cell nuclei contain levels of DNA comparable to dividing root cells, the 2C level (i.e., one unreplicated copy of the nuclear DNA). Leaf trichome nuclei had elevated ploidy levels of 4C, 8C, 16C, 32C, and 64C, and their cytology suggested that the polyploidy represents a form of polyteny. The nuclei of epidermal pavement cells were 2C, 4C, and 8C in stem epidermis, and 2C, 4C, 8C, and 16C in leaf epidermis. Morphometry of epidermal pavement cells revealed a direct proportionality between nuclear DNA level and cell size. A consideration of the development process suggests that the cells of highest ploidy level are developmentally oldest; consequently, the developmental pattern of epidermal tissues can be read from the ploidy pattern of the cells. This observation is relevant to theories of stomate spacing and offers opportunities for genetic analysis of the endopolyploidy/polyteny phenomenon.

18.
Indian J Exp Biol ; 30(6): 512-7, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1506034

RESUMO

Alcoholic extracts of 50 botanically identified species of marine flora have been screened for a wide range of biological activities. Of these, 2 extracts exhibited anti-amoebic and antiviral activity each, 3 of them had anti-implantation activity; 9 had hypoglycaemic activity while hypotensive activity was associated with 11 extracts; 14 extracts were found to be diuretic and 1 of them had anti-inflammatory activity. Further, 10 of these extracts exhibited 2 types of activities while a combination of 3 and 4 types of activities was observed in one extract each. Follow-up studies have been carried out in some plants with confirmed activity. The active principles and results of these studies are reported.


Assuntos
Extratos Vegetais/farmacologia , Índia , Oceanos e Mares
20.
Anc Sci Life ; 12(1-2): 248-50, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22556595

RESUMO

The present paper coins a new term Ethno-Oceanobiology, a new sub-discipline of ethnobiology and deals with the uses of some marine plants by tribals of Andaman and Nicobar Islands.

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