RESUMO
We present a measurement of R_{K^{*}}, the branching fraction ratio B(BâK^{*}µ^{+}µ^{-})/B(BâK^{*}e^{+}e^{-}), for both charged and neutral B mesons. The ratio for the charged case R_{K^{*+}} is the first measurement ever performed. In addition, we report absolute branching fractions for the individual modes in bins of the squared dilepton invariant mass q^{2}. The analysis is based on a data sample of 711 fb^{-1}, containing 772×10^{6} BB[over ¯] events, recorded at the Ï(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The obtained results are consistent with standard model expectations.
RESUMO
The dark photon A^{'} and the dark Higgs boson h^{'} are hypothetical constituents featured in a number of recently proposed dark sector models. Assuming prompt decays of both dark particles, we search for their production in the so-called Higgstrahlung channel e^{+}e^{-}âA^{'}h^{'}, with h^{'}âA^{'}A^{'}. We investigate ten exclusive final states with A^{'}âe^{+}e^{-}, µ^{+}µ^{-}, or π^{+}π^{-} in the mass ranges 0.1 GeV/c^{2}
RESUMO
Using a sample of 771.6×10(6) ÏÏ(4S) decays collected by the Belle experiment at the KEKB e(+)e(-) collider, we observe, for the first time, the transition Ï(4S)âηh(b)(1P) with the branching fraction B[Ï(4S)âηh(b)(1P)]=(2.18±0.11±0.18)×10(-3) and we measure the h(b)(1P) mass M(h(b)(1P))=(9899.3±0.4±1.0) MeV/c(2), corresponding to the hyperfine (HF) splitting ΔM(HF)(1P)=(0.6±0.4±1.0) MeV/c(2). Using the transition h(b)(1P)âγη(b)(1S), we measure the η(b)(1S) mass M(η(b)(1S))=(9400.7±1.7±1.6) MeV/c(2), corresponding to ΔM(HF)(1S)=(59.6±1.7±1.6) MeV/c(2), the η(b)(1S) width Γ(η(b)(1S))=(8(-5)(+6)±5) MeV/c(2) and the branching fraction B[h(b)(1P)âγη(b)(1S)]=(56±8±4)%.
RESUMO
We report the clinical, ultrastructural, immunophenotypic and virological features of nine cases of a rare type of mature T cell disorder formerly designated Sezary cell leukaemia. All patients presented with lymphocytosis ranging from 12.7 to 133 x 10(9)/l, bone marrow infiltration, splenomegaly and lymphadenopathy. Skin involvement was absent at presentation but developed as a terminal event in two patients, one of whom showed a pattern of dermal infiltration different from that characteristic of Sezary syndrome. Cells from eight cases bore a mature T cell phenotype and electronmicroscopy revealed lymphocytes with cerebriform nuclei resembling Sezary cells. All cases except one were HTLV-I negative. Patients were treated with various chemotherapy regimens but with poor outcome, the median survival being 13 months. Laboratory and clinical data suggest great similarity between Sezary cell leukaemia and T prolymphocytic leukaemia (T-PLL), namely coexpression of CD4 and CD8 (3/9 cases), identical chromosomal abnormalities in the three cases studied (isochromosome 8q plus inversion 14 or t(X;14)(q28;q11)) and a remarkable sensitivity to CAMPATH-1H (complete remission of 21 months' duration in one patient), suggesting that this entity could be considered a variant form of T-PLL. The alternative diagnosis of adult T cell leukaemia/lymphoma could not be excluded in one patient in whom positive HTLV-I serology was documented.
Assuntos
Leucemia Prolinfocítica/diagnóstico , Leucemia de Células T/diagnóstico , Síndrome de Sézary/diagnóstico , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Leucemia Prolinfocítica/imunologia , Leucemia Prolinfocítica/patologia , Leucemia de Células T/imunologia , Leucemia de Células T/patologia , Masculino , Pessoa de Meia-Idade , Síndrome de Sézary/patologiaRESUMO
Poorly differentiated synovial sarcoma is a variant of synovial sarcoma in which the tumor cells lack the bland spindle cell appearance of the usual type monophasic synovial sarcoma. Although poorly differentiated synovial sarcoma has been recognized as an entity for many years, no series addressing the clinicopathologic features of this variant have appeared. We describe the histologic, immunohistologic, and molecular findings of a series of 20 poorly differentiated synovial sarcomas. Three types of poorly differentiated synovial sarcoma can be recognized: a large cell epithelioid variant, a small cell variant, and a high-grade spindle cell variant. Epithelial membrane antigen reactivity was seen in 95% of cases, and reactivity for cytokeratin was seen in 42%. The S100 antigen was expressed in 63% of cases. Electron microscopic findings in poorly differentiated synovial sarcoma parallel those found in usual type synovial sarcoma. In 10 cases, material was available for molecular studies; 9 of 10 cases showed the presence of t(X;18) or the associated fusion gene product. These data indicate that poorly differentiated synovial sarcoma is a lesion that shares immunologic, ultrastructural, and molecular characteristics with the usual synovial sarcoma. Follow-up data were available in 16 patients with a mean follow-up of 39 months. Eight patients died with a mean survival time of 33 months. Poorly differentiated synovial sarcoma is a variant of synovial sarcoma that may be associated with a poor prognosis.
Assuntos
Sarcoma Sinovial/genética , Sarcoma Sinovial/patologia , Neoplasias de Tecidos Moles/genética , Neoplasias de Tecidos Moles/patologia , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/análise , Criança , Cromossomos Humanos Par 18/genética , Sondas de DNA/química , DNA de Neoplasias/análise , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoma Sinovial/química , Neoplasias de Tecidos Moles/química , Translocação Genética , Cromossomo X/genéticaRESUMO
Pancreastatin is a peptide isolated from porcine pancreas which has insulin-suppressive actions in vitro and sequence homology with chromogranin A. Using radioimmunoassay and immunocytochemistry we investigated whether pancreastatin has a more widespread distribution and a possible endocrine role in the pig. Pancreastatin immunoreactivity was found in plasma, adrenal gland, pancreas, anterior pituitary and throughout the gastrointestinal tract. The immunoreactivity was colocalized with chromogranin immunoreactivity in endocrine cells and ultrastructurally (in the pancreas) to storage granules. Characterization of pancreastatin-like immunoreactivity, using gel permeation and high performance liquid chromatography, separated 3 different pancreastatin-like immunoreactive forms: one molecular form, indistinguishable from synthetic pancreastatin 1-49, was predominant in pancreas and thyroid and released into the circulation postprandially. However, a high dose (greater than 1 nmol/l) infusion of pancreastatin 33-49 (the biologically active moiety in vitro) into conscious pigs had no effect on either basal or glucose-stimulated insulin secretion.
Assuntos
Hormônios Pancreáticos/análise , Suínos/metabolismo , Glândulas Suprarrenais/análise , Animais , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Cromogranina A , Duodeno/análise , Feminino , Imuno-Histoquímica , Masculino , Especificidade de Órgãos , Pâncreas/análise , Hormônios Pancreáticos/sangue , Radioimunoensaio , Glândula Tireoide/análiseRESUMO
We describe an unusual case of Sezary syndrome which transformed into a large T-cell non Hodgkin's lymphoma (immunoblastic) in a black man of Caribbean descent with negative HTLV-I serology and no evidence of HTLV-I infection by DNA analysis using sensitive techniques. The disease presented as a small-cell Sezary syndrome and transformed in an inguinal lymph node one year from diagnosis. Immunological markers in the small and large cells showed a mature T-cell phenotype CD4+, CD8- with expression of T-cell activation markers and a high proliferative rate. Ultrastructural analysis confirmed small Sezary cells with serpentine nucleus in the peripheral blood and immunoblasts in the lymph node. Cytogenetics demonstrated complex clonal chromosome abnormalities with involvement of 7q35, the locus for the beta chain of the T-cell receptor (TCR). Southern-blot analysis showed the same rearrangement of the TCR beta, gamma, delta chain genes in lymph node and peripheral blood cells. Antibodies to HTLV-I were not detected in the serum by ELISA and particle agglutination (PA) nor HTLV-I specific sequences were demonstrated by nested polymerase chain reaction with primers to the envelope proteins, LTR and tax/rex of HTLV-I in both tissues, blood and lymph node. The disease had an aggressive course and was refractory to therapy; the patient died of progressive disease 28 months from presentation. Two unusual features characterised this patient's illness: immunoblastic transformation of a Sezary syndrome in a patient of Afro-Caribbean origin without evidence of HTLV-I DNA sequences and negative HTLV-I serology and the atypical lymph node histology resembling ATLL.
Assuntos
Linfoma de Células T/microbiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/microbiologia , Síndrome de Sézary/patologia , Sequência de Bases , Aberrações Cromossômicas/patologia , Bandeamento Cromossômico , Transtornos Cromossômicos , Primers do DNA/química , DNA Viral/análise , Rearranjo Gênico do Linfócito T , Genes myc , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Imunofenotipagem , Jamaica/etnologia , Linfoma de Células T/patologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologiaRESUMO
Preference trials were conducted with mature ponies. In Trial 1, oats were compared with oats plus sucrose. Four of six pony geldings selected oats plus sucrose, but one pony demonstrated a dislike for sucrose and one selected from the bucket on the right side regardless of content. Oats, maize, barley, rye and wheat were compared in Trial 2 using six mature pony mares. Oats were the preferred grain, with maize and barley ranking second and third respectively. Wheat and rye were the least preferred. Even though the ponies demonstrated preference, the total intake at a given meal was not greatly depressed when only the less palatable grains were fed. In Trial 3, pony mares selected a diet containing 20 per cent dried distillers' grain and 80 per cent of a basal mixed diet of maize, oats, wheat bran, soybean meal, limestone and molasses over 100 per cent basal mixed diet, but selected the basal diet over diets containing 20 per cent blood meal, beet pulp or meat and bone meal and 80 per cent basal diet. They did not differentiate against diets containing 20 per cent alfalfa meal or 10 or 5 per cent meat and bone meal when the diets were compared to the basal mixed diet.
Assuntos
Ração Animal , Preferências Alimentares , Cavalos/fisiologia , Animais , Comportamento Alimentar/fisiologia , Feminino , MasculinoRESUMO
The effects of continuous wave ultrasound on three different classes of biosystems have been investigated at a frequency of 1.5 MHz. The criteria for cavitation are given, and these are applied to experimentally observed growth retardation of plant roots, cell death and DNA degradation in bacteria and pyknosis of human lymphocytes. An attempt is being made to find common physical mechanisms for all these biological responses, and cavitation processes in particular are examined here. A description is given of the techniques used to monitor the presence of cavitation, and indirect evidence, drawn from pulsed field and elevated pressure experiments, is presented to show that other-non-linear processes are also operative.
Assuntos
Ultrassom , Acústica , Biologia , Membrana Celular/ultraestrutura , DNA Bacteriano , Escherichia coli/citologia , Estudos de Avaliação como Assunto , Humanos , Linfócitos/citologia , Oscilometria , Desenvolvimento VegetalRESUMO
Whilst a large body of plot and field-scale research exists on the sources, behaviour and mitigation of diffuse water pollution from agriculture, putting this evidence into a practical, context at large spatial scales to inform policy remains challenging. Understanding the behaviour of pollutants (nutrients, sediment, microbes and pesticides) and the effectiveness of mitigation strategies over whole catchments and long timeframes requires new, interdisciplinary approaches to organise and undertake research. This paper provides an introduction to the demonstration test catchments (DTC) programme, which was established in 2009 to gather empirical evidence on the cost-effectiveness of combinations of diffuse pollution mitigation measures at catchment scales. DTC firstly provides a physical platform of instrumented study catchments in which approaches for the mitigation of diffuse agricultural water pollution can be experimentally tested and iteratively improved. Secondly, it has established national and local knowledge exchange networks between researchers and stakeholders through which research has been co-designed. These have provided a vehicle to disseminate emerging findings to inform policy and land management practice. The role of DTC is that of an outdoor laboratory to develop knowledge and approaches that can be applied in less well studied locations. The research platform approach developed through DTC has brought together disparate research groups from different disciplines and institutions through nationally coordinated activities. It offers a model that can be adopted to organise research on other complex, interdisciplinary problems to inform policy and operational decision-making.
Assuntos
Monitoramento Ambiental/métodos , Modelos Teóricos , Poluição da Água/estatística & dados numéricos , Agricultura , Técnicas de Apoio para a Decisão , Inglaterra , Política Ambiental , País de Gales , Poluição da Água/análiseAssuntos
Intestinos/efeitos dos fármacos , Consumo de Oxigênio/efeitos da radiação , Efeitos da Radiação , Radiossensibilizantes/farmacologia , Animais , Feminino , Hipóxia , Intestinos/efeitos da radiação , Camundongos , Camundongos Endogâmicos , Consumo de Oxigênio/efeitos dos fármacos , Radiossensibilizantes/administração & dosagem , Fatores de TempoRESUMO
The effects of X-rays and neutrons on human lymphocytes in vitro has been tested. Radiation sensitivity of untransformed lymphocytes was assessed by the appearance of pyknotic cells, and the response of cells after stimulation by phyto-haemagglutinin was tested (a) morphologically and (b) by changes in DNA synthesis, using a labelled thymidine analogue. The data obtained for interphase cells suggest that lymphocytes are a mixed cell population with an insensitive component forming about 20 per cent of the population. The percentage of normal cells observed after both X-ray and neutron irradiation lie on the same dose--effect curve giving an r.b.e. of one. A biphasic response is seen after PHA stimulation with both tests of damage indicating at least two sub-populations of lymphocytes and these give r.b.e. values in the range 1.95 to 2.45. Providing the in vivo response is similar to that in vitro the r.b.e. for damage to circulating lymphocytes will be small and the reduction in white cell count will not therefore be a major factor limiting dose in neutron therapy.
Assuntos
Nêutrons Rápidos , Ativação Linfocitária/efeitos da radiação , Linfócitos/efeitos da radiação , Nêutrons , Sobrevivência Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Humanos , Técnicas In Vitro , Masculino , Raios XRESUMO
Human lymphocyte cultures are exposed to 1.5 MHz continuous wave ultrasound, and it is demonstrated that cell death, as monitored by pyknosis, follows immediately on sonication at intensities within the usual therapeutic range (less than 1.7 W/cm2,spatial average). The number of cells affected is determined by the ultrasound intensity only, but the rate at which they proceed through their pyknosis cycle is modified by both the intensity and the duration of exposure. There is a clear indication of an intensity threshold for the effect approximately 1.1 W/cm2. Pulsed 1.5 MHz ultrasound (70 mus, 1 :1 pulses, 1.7 W/cm2 space-time average) results in a 15-20 hour delay in the measurable response to sonication. It is shown that the intracellular presence of a lysosomal-enzyme inhibitor strongly modifies the course of the ultrasound action. Evidence is presented to suggest that the basic interaction mechanism is via a cavitation process, but there are some difficulties with this interpretation, which are also discussed.
Assuntos
Linfócitos/patologia , Sonicação/efeitos adversos , Ultrassom/efeitos adversos , Núcleo Celular , Sobrevivência Celular , Células Cultivadas , Cortisona/farmacologia , Humanos , Linfócitos/ultraestrutura , Lisossomos/enzimologia , Masculino , Terapia por Ultrassom/efeitos adversosRESUMO
Ossifying fibromyxoid tumor of soft parts (OFMT) is a recently named soft tissue tumor of uncertain nature. A case is described that presented in a 13-year-old boy as a discrete mass in the muscles of the lower abdominal wall. Light microscopy showed, in addition to the typical features of this entity, microcysts formed by accumulations of the myxoid stroma. Bone formation was lacking. Tumor cells were strongly immunoreactive for vimentin and glial fibrillary acidic protein and weakly so for S-100 protein. A few cells stained for desmin and alpha-smooth muscle actin. Ultrastructurally, there were abundant, patternless cytoplasmic intermediate filaments; short, poorly interdigitating processes; and discontinuous segments of thick external lamina. In addition, several cells contained typical ribosome-lamella complexes in small groups. Ribosome-lamella complexes occur in neoplastic hematopoietic cells but are uncommon in solid tumors, particularly those affecting the soft tissues. These findings extend the range of appearances described for OFMT, which is added to the list of tumors in which ribosome-lamella complexes have been demonstrated. The balance of evidence suggests that OFMT may represent a peripheral nerve sheath tumor of low-grade malignancy, although the picture is incomplete.
Assuntos
Fibroma/ultraestrutura , Ribossomos/ultraestrutura , Neoplasias de Tecidos Moles/ultraestrutura , Células Estromais/ultraestrutura , Adolescente , Fibroma/diagnóstico , Fibroma/patologia , Humanos , Imuno-Histoquímica , Masculino , Microscopia EletrônicaRESUMO
We find that at pH 6.1 diethyl pyrocarbonate inhibits estrogen binding to its receptor protein in rat uterus. Hydroxylamine partially reverses this inhibition and estrogen partially protects its receptor protein from this inhibition. We suggest that the estrogen receptor protein in rat uterus contains a nucleophilic site that either overlaps or is near the estrogen binding site. Based on the pH of inhibition reaction, the receptor concentration in the experiment, and the partial reversal of the inhibition by hydroxylamine, we suggest that this site contains a histidine residue or possibly an unusually reactive tyrosine residue that is important for estrogen binding.
Assuntos
Dietil Pirocarbonato/farmacologia , Estrogênios/metabolismo , Formiatos/farmacologia , Receptores de Estrogênio/efeitos dos fármacos , Útero/metabolismo , Animais , Sítios de Ligação , Citosol/metabolismo , Feminino , Histidina , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Ratos , Ratos Endogâmicos , Receptores de Estrogênio/metabolismoRESUMO
The relationship between radiosensitivity and the partial pressure of oxygen (PO2) in the inspired gas has been established for radiation pneumonitis as a measure of lung damage following irradiation of the mouse thorax. The radiosensitivity at low PO2 (0-1 per cent) fitted the linear transformation of the Alper, Howard-Flanders relationship giving a K value for lung tissue of 1.35 per cent oxygen with an oxygen enhancement ratio, m, of 2.13. The radiosensitivity at higher PO2 (5-21 per cent) did not fit the Alper, Howard-Flanders relationship probably because the PO2 of the inspired gas was greater than the PO2 in the alveolus. At the low PO2 levels in the inspired gas, back diffusion of oxygen from blood into the alveolus may lead to errors in the estimated value of K. If the low value of m is due to this 'contaminating' oxygen from blood then by taking a higher value for m, the amount of contaminating oxygen can be calculated (0.23 per cent) and a 'true' value for K(1.1 per cent) determined. Other uncertainties in this estimate of K due to the radiolytic consumption of oxygen and possible inadequacies in equilibration are discussed. Allowing for the uncertainties, it is concluded that the K value for lung damage lies towards the upper end of the range of K values measured for cells in vitro.
Assuntos
Pulmão/efeitos da radiação , Oxigênio/fisiologia , Animais , Feminino , Camundongos , Pressão Parcial , Pneumonia/etiologia , RespiraçãoRESUMO
Sezary cell leukaemia (SCL) is a mature T-cell leukaemia with characteristic cerebriform nuclei, whereas Sezary syndrome (SS) involves a mature T-cell lymphoma with a similar nuclear morphology. We have examined these diseases by cytogenetics chromosome painting and fluorescence in situ hybridization (FISH). Both diseases had complex cytogenetic abnormalities. All three cases of SCL investigated had inv(14)(q11:q32) and two had iso(8q). No case of SS had these abnormalities but, instead, iso(17q) or 17p+ was present in the three cases of SS investigated and FISH indicated loss of heterozygosity due to deletion of a region at 17p 13 that included the tumour suppressor gene P53, implicating it in this malignancy. One case of SCL had iso(17q). The abnormalities of chromosomes 8 and 14 in SCL are commonly observed in T-prolymphocytic leukaemia (T-PLL) and suggest that SCL may be a variant of T-PLL rather than of SS.