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1.
Integr Org Biol ; 6(1): obae005, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38558855

RESUMEN

Animal phyla are distinguished by their body plans, the ways in which their bodies are organized. A distinction is made, for example, among phyla with bodies of many segments (metameric; e.g., annelids, arthropods, and chordates), others with completely unsegmented bodies (americ; e.g., flatworms and mollusks), and a few phyla with bodies of 2 or 3 regions (oligomeric; e.g., echinoderms and hemichordates). The conventional view of echinoderms as oligomeric coelomates adequately considers early development, but it fails to recognize the metameric body plan that develops in the juvenile rudiment and progresses during indeterminate adult growth. As in the 3 phyla traditionally viewed to be metameric (annelids, arthropods, and chordates), metamery, or metamerism, in echinoderms occurs by (1) subterminal budding of (2) serially repeated components of (3) mesodermal origin. A major difference in most echinoderms is that metamery is expressed along multiple body axes, usually 5. The view of a metameric echinoderm might invite new discussions of metazoan body plans and new approaches to the study of morphogenesis, particularly in comparative treatments with annelids, arthropods, and chordates.

2.
Integr Org Biol ; 5(1): obad013, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37151601

RESUMEN

Branching of arms and presence of pedicellariae are characters among ophiuroids found only in the order Euryalida (snakestars and basketstars). Family Asteronychidae has neither character; family Euryalidae has 2 small clades with branched arms; and family Gorgonocephalidae has all species with pedicellariae and 3 or 4 clades with branched arms. Despite the rare occurrence of these characters in the Ophiuroidea, they might be key adaptations within the Euryalida that have led to relatively high diversification. Sister-group comparison of the distribution of these 2 characters among taxa indicates that neither character alone explains diversity patterns within the order. In particular, branching restricted to the tips of arms seems not strongly adaptive, probably for the lack of integration of basal forks with the disc. On the other hand, 2 clades of gorgonocephalids with basal branching exceed their snakestar sister groups in numbers of species, indicating an advantage of branching within the family. Unfortunately, the analysis cannot benefit from statistics, for at least 5 independent comparisons are required for a one-tailed sign test. Because branching and pedicellariae are probably not independent variables, future sister-group comparisons should be done only within the Gorgonocephalidae once clade structure is better clarified with increased taxon sampling (10 currently missing genera) and resolution of intra-generic inconsistencies in the most recent cladograms available. Branching might confer upon gorgonocephalid basketstars a more efficient use of pedicellariae for upstream capture of zooplankton over their snakestar relatives as well as over the Euryalidae, which retain ancestral downstream capture by mucus-laden podia.


GermanDie Verzweigung der Arme und das Vorhandensein von Pedicellarien sind Merkmale unter Ophiuroiden, die nur in der Ordnung Euryalida (Schlangensterne mit unverzweigten Armen und Korbsterne mit verzweigten Armen) vorkommen. Die Familie Asteronychidae hat kein Merkmal; die Familie Euryalidae hat zwei kleine Kladen mit verzweigten Armen; und die Familie Gorgonocephalidae hat alle Arten mit Pedicellarien und drei oder vier Kladen mit verzweigten Armen. Trotz des seltenen Vorkommens dieser Merkmale in den Ophiuroidea könnten sie Schlüsselanpassungen innerhalb der Euryalida sein, die zu einer relativ hohen Diversifizierung geführt haben. Eine Schwestergruppenanalyse der Verteilung dieser beiden Merkmale unter den Taxa zeigt, dass keines der Merkmale allein die Diversitätsmuster innerhalb der Ordnung erklärt. Insbesondere die auf die Armspitzen beschränkte Verzweigung scheint nicht stark adaptiv zu sein, wahrscheinlich wegen fehlender Integration von Basalgabeln in die Scheibe. Andererseits übertreffen zwei Kladen von Gorgonocephaliden mit basaler Verzweigung ihre Schlangenstern-Schwestergruppen in der Anzahl der Arten, was auf einen Vorteil der Verzweigung innerhalb der Familie hinweist. Leider kann die Analyse nicht von Statistiken profitieren, da für einen einseitigen Vorzeichentest mindestens fünf unabhängige Vergleiche erforderlich sind. Da Verzweigung und Pedicellariae wahrscheinlich keine unabhängigen Variablen sind, sollten zukünftige Schwestergruppenvergleiche nur innerhalb der Gorgonocephalidae durchgeführt werden, sobald die Klade-Struktur durch vermehrte Taxon-Stichproben (10 derzeit fehlende Gattungen) und durch Auflösung von Inkonsistenzen innerhalb der Gattungen in den neuesten verfügbaren Kladogrammen besser aufgeklärt ist. Die Verzweigung könnte gorgonocephaliden Korbsternen eine effizientere Nutzung von Pedicellarien für den stromaufwärts gelegenen Fang von Zooplankton gegenüber ihren Schlangenstern-Verwandten sowie gegenüber den Euryalidae verleihen, die den stromabwärts gelegenen Fang durch schleimbeladene Füsschen der Vorfahren beibehalten.

3.
J Clin Invest ; 98(4): 930-6, 1996 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-8770864

RESUMEN

The hexosamine biosynthetic pathway has been hypothesized to be involved in mediating some of the toxic effects of hyperglycemia. Glutamine:fructose-6-phosphate amidotransferase (GFA), the first and rate limiting enzyme of the hexosamine biosynthetic pathway, was overexpressed in skeletal muscle and adipose tissue of transgenic mice. A 2.4-fold increase of GFA activity in muscle of the transgenic mice led to weight-dependent hyperinsulinemia in random-fed mice. The hyperinsulinemic-euglycemic clamp technique confirmed that transgenic mice develop insulin resistance, with a glucose disposal rate of 68.5 +/- 3.5 compared with 129.4 +/- 9.4 mg/kg per min (P < 0.001) for littermate controls. The decrease in the glucose disposal rate of the transgenic mice is accompanied by decreased protein but not mRNA levels of the insulin-stimulated glucose transporter (GLUT4). These data support the hypothesis that excessive flux through the hexosamine biosynthesis pathway mediates adverse regulatory and metabolic effects of hyperglycemia, specifically insulin resistance of glucose disposal. These mice can serve as a model system to study the mechanism for the regulation of glucose homeostasis by hexosamines.


Asunto(s)
Glutamina-Fructosa-6-Fosfato Transaminasa (Isomerizadora)/fisiología , Hexosaminas/metabolismo , Resistencia a la Insulina , Ratones Transgénicos , Proteínas Musculares , Tejido Adiposo/metabolismo , Animales , Femenino , Expresión Génica , Glucosa/metabolismo , Transportador de Glucosa de Tipo 4 , Hemoglobina Glucada/metabolismo , Hemoglobinas/metabolismo , Masculino , Ratones , Proteínas de Transporte de Monosacáridos/genética , Músculos/metabolismo , ARN Mensajero/genética , Transgenes/genética
4.
J Thorac Cardiovasc Surg ; 69(6): 922-6, 1975 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1134117

RESUMEN

Fibrinolysis in cyanotic and acyanotic children has been studied before and after open intracardiac operations. Preoperatively, shorter lysis times were found in the cyanotic group. Lysis times in individual patients varied at different times before operation. Precise documentation of the timing of fibrinolysis determinations is necessary. The lysis times appear to be affected by variables such as fasting, stress, and anesthesia in addition to perfusion. Postoperatively there was no excessive fibrinolysis in either the cyanotic or acyanotic group, the groups showing no differences. No significant alterations in plasma fibrinogen were present before or after perfusion with the pediatric Bentley Temptrol system.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/efectos adversos , Cianosis/sangre , Fibrinógeno , Fibrinólisis , Oxigenadores/efectos adversos , Anestesia/efectos adversos , Niño , Cardiopatías Congénitas/sangre , Cardiopatías Congénitas/cirugía , Humanos , Fenómenos Fisiológicos de la Nutrición , Complicaciones Posoperatorias/etiología , Estrés Psicológico , Factores de Tiempo
5.
Science ; 168(3931): 606-7, 1970 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-17806785
6.
Br J Radiol ; 50(595): 508-12, 1977 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-68793

RESUMEN

Fifty two cases of squamous cell carcinoma were studied using indium-111 labelled Bleomycin. The overall accuracy of localization by static imaging alone was 80%. Detection of lung and gynaecological tumours was most consistent, while oesophageal tumours were the most commonly missed. Imaging within a few hours of administration of the radiopharmaceutical was found to be as effective as imaging at the recommended time of at least 24 hours. Inflammatory lesions giving false positive scans could be differentiated from tumour tissue by the technique of dynamic imaging. Maximum activity occurred in tumour tissue on average ten minutes after the peak for normal tissue. This difference was used to improve the detection of known tumours to 90%.


Asunto(s)
Bleomicina , Carcinoma de Células Escamosas/diagnóstico , Cintigrafía , Adulto , Anciano , Bleomicina/metabolismo , Carcinoma de Células Escamosas/metabolismo , Femenino , Humanos , Indio , Masculino , Persona de Mediana Edad , Radioisótopos , Factores de Tiempo
7.
J Am Mosq Control Assoc ; 14(2): 214-5, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9673926

RESUMEN

Fourteen species of mosquito were collected from Utila, Bay Islands, Honduras, during May 1996 and March 1997. Twelve species represent new records for the Bay Islands, and one species is a new record for Honduras.


Asunto(s)
Culicidae , Aedes , Animales , Anopheles , Culex , Honduras
8.
Acta Virol ; 37(6): 523-8, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8010191

RESUMEN

The sequence of 380 nucleotides upstream of the start codon of the open reading frame (ORF) of the coat protein of the carlavirus Helenium virus (HelVS) was determined from cloned cDNA. This portion of the viral RNA contained one complete ORF encoding a protein of 7 K which had homology with similar sized proteins from other members of the carla- and potexvirus groups. Sequence data was also obtained beyond the start codon of the 7 K ORF into what was presumed to be the 12 K protein gene of the previously identified triple gene block of carla- and potexviruses. Significant sequence similarity of 46.3% and 41.6% was evident at the amino acid level with the equivalent regions of the 12 K proteins of potato virus S, Andean strain (PVSA) and potato virus M (PVM), respectively, with 25.4% similarity detected with the equivalent region of potato virus X (PVX).


Asunto(s)
Cápside/genética , Carlavirus/genética , Genes Virales/genética , Secuencia de Aminoácidos , Secuencia de Bases , Cápside/química , ADN Complementario , Regulación Viral de la Expresión Génica/genética , Proteínas de la Membrana , Datos de Secuencia Molecular , Sistemas de Lectura Abierta/genética , ARN Viral/análisis , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Transcripción Genética , Proteínas Virales
9.
Psychol Rep ; 73(3 Pt 2): 1164-6, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8115568

RESUMEN

The relationship between sex-typing (androgynous vs traditional) and differences in fantasies of 19 men and 37 women was investigated. They completed May's test as a measure of fantasy pattern and the Bem Sex-role Inventory to ascertain sex-type. Analysis indicated that, while fantasy patterns were related to gender as expected from May's work, they were not related to sex-typing.


Asunto(s)
Fantasía , Identidad de Género , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Inventario de Personalidad , Psicometría , Estereotipo
13.
Clin Radiol ; 33(1): 101-8, 1982 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6175465

RESUMEN

Long-term results are described in a group of 119 patients treated by a combination of methotrexate, vinca alkaloids and bleomycin and observed over a period of seven years. Details are given of the chemotherapy used, together with modifications designed to reduce its toxicity. There was an overall objective response in 48% of the patients and this was site dependent with cancer of the head and neck faring best (68%). Overall survival was 8% at two years and was better in patients showing an objective response and also in those whose performance status was improved by treatment. Previous radiotherapy did not appear to affect response adversely. Further studies are proposed with the addition of a cycle specific agent to a modification of the schedule used.


Asunto(s)
Bleomicina/administración & dosificación , Carcinoma de Células Escamosas/tratamiento farmacológico , Metotrexato/administración & dosificación , Alcaloides de la Vinca/administración & dosificación , Adulto , Anciano , Bleomicina/efectos adversos , Carcinoma de Células Escamosas/mortalidad , Quimioterapia Combinada , Femenino , Humanos , Metotrexato/efectos adversos , Persona de Mediana Edad , Factores de Tiempo , Alcaloides de la Vinca/efectos adversos
14.
Virology ; 253(1): 115-24, 1999 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-9887324

RESUMEN

Mutational analysis has been used to investigate cis-acting sequences in the 3'- and 5'-untranslated regions of red clover necrotic mosaic virus RNA2 required for replication in the presence of wild-type RNA1. Deletion of a sequence near the 3' end of RNA2, which is potentially capable of forming a stable stem-loop structure, abolished the ability of RNA2 to replicate in Nicotiana clevelandii protoplasts, as judged by the failure to detect production of either the positive or negative RNA strand. A base-paired structure in the stem was shown to be essential for replication, but a mutant RNA2 in which every base of the stem had been altered was able to replicate in N. clevelandii protoplasts, to produce lesions on leaves of Vigna unguiculata plants, and to infect N. clevelandii plants systemically. However, changing three bases in the loop of the potential stem-loop structure abolished the replication of RNA2. Upstream sequences in the 3'-untranslated region of RNA2 were also shown to be important for RNA2 replication. Deletions in the 5'-untranslated region of RNA2 showed that sequences across the whole of this region were needed for production of the positive strand but not for production of the negative strand. Some of the cis-acting sequences required for replication of RNA2 have almost identical counterparts in RNA1, but others appear to be unique to RNA2.


Asunto(s)
Virus del Mosaico/genética , Análisis de Secuencia de ARN , Secuencia de Bases , Northern Blotting , Western Blotting , Datos de Secuencia Molecular , Virus del Mosaico/fisiología , Mutación , Conformación de Ácido Nucleico , Enfermedades de las Plantas/virología , Plantas Tóxicas , Reacción en Cadena de la Polimerasa , Mapeo Restrictivo , Nicotiana/virología , Tombusviridae/genética , Tombusviridae/fisiología , Proteínas Virales/genética , Replicación Viral
15.
Br J Haematol ; 35(3): 437-40, 1977 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-870006

RESUMEN

A mica adsorption technique was used to prepare fibrinogen and early fibrin polymers for examination in the transmission electron microscope. Globular particles 10 +/- 3 nm in diameter were observed and a model for the process of aggregation of these globules into fibrous units is proposed. A comparison is made between the results obtained by the mica adsorption technique and those obtained by conventional preparation techniques involving fixation and staining.


Asunto(s)
Fibrina , Fibrinógeno , Microscopía Electrónica/métodos , Humanos , Conformación Proteica
16.
Am J Gastroenterol ; 71(5): 481-4, 1979 May.
Artículo en Inglés | MEDLINE | ID: mdl-453141

RESUMEN

Acute cholecystitis is a rare complication of systemic brucellosis. This report details the occurrence of acute noncalculous cholecystitis in which Brucella suis was cultured from both the blood and the gallbladder. A discussion of the various diagnostic tests and the recommended therapy for brucellosis is included.


Asunto(s)
Brucelosis/complicaciones , Colecistitis/etiología , Enfermedad Aguda , Adulto , Brucella/aislamiento & purificación , Brucelosis/tratamiento farmacológico , Brucelosis/microbiología , Colecistitis/microbiología , Vesícula Biliar/microbiología , Humanos , Masculino , Tetraciclina/uso terapéutico
17.
Arch Virol ; 144(7): 1451-61, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10481751

RESUMEN

When present as a transcript leader the 5' untranslated sequence from the potato virus S genomic RNA molecule enhances translation of a downstream open reading frame both in vitro and in vivo. Translational enhancement was 30-fold in rabbit reticulocyte lysate and 15 fold in wheat germ above translation from a transcript with a synthetic leader. Transient expression experiments using tobacco protoplasts and particle bombardment of leaf tissue resulted in enhancement of fourteen and five-fold, respectively, above translation with a synthetic leader. In stably transformed plants the PVS 5'UTR enhanced translation yield ca. 5-fold compared with a synthetic 5'UTR.


Asunto(s)
Regiones no Traducidas 5'/metabolismo , Carlavirus/genética , Elementos de Facilitación Genéticos , Biosíntesis de Proteínas , ARN Viral/metabolismo , Solanum tuberosum/virología , Regiones no Traducidas 5'/química , Animales , Secuencia de Bases , Datos de Secuencia Molecular , ARN Viral/química , Conejos
18.
J Chromatogr ; 338(2): 335-45, 1985 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-2581984

RESUMEN

Comprehensive pharmacokinetic studies could realise a greater potential for the antitumour agent triethylenethiophosphoramide (ThioTEPA), and these would be aided by the development of a selective and sensitive assay. After extraction of ThioTEPA and its metabolite, triethylenephosphoramide (TEPA), from plasma using Sep-Pak C18 cartridges, the compounds were separated by capillary chromatography, detected using a nitrogen detector and quantified by reference to an internal standard, hexaethylphosphoramide. The limits of sensitivity were 1-5 ng/ml. Analytical recoveries were 74 and 95%, for TEPA and ThioTEPA, respectively, in the therapeutic range. At similar concentrations, extents of protein binding, determined by ultrafiltration, were not significant. Preliminary investigations of the elimination of ThioTEPA show that drug loss occurs more quickly in mice than in humans and in both species the metabolite is extensively recycled.


Asunto(s)
Azirinas/sangre , Tiotepa/sangre , Trietilenofosforamida/sangre , Animales , Cromatografía de Gases , Femenino , Semivida , Humanos , Cinética , Ratones , Nandrolona/análogos & derivados , Nandrolona/farmacología , Unión Proteica , Especificidad de la Especie , Ultrafiltración , gammaglobulinas/metabolismo
19.
Br J Surg ; 64(2): 134-8, 1977 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-407964

RESUMEN

The outcome in 254 patients with all stages of breast cancer treated by combination chemotherapy is presented. All the patients were treated 10 or more years ago. The 10-year survival rate for Stages I and II combined is 60 per cent, in Stage III 19 per cent and in Stage IV 3 per cent. The combined rate in Stages I and II differed markedly according to hormonal status. In premenopausal patients the rate was 84 per cent compared with 42 per cent in postmenopausal patients.


Asunto(s)
Andrógenos/uso terapéutico , Neoplasias de la Mama/mortalidad , Tiotepa/uso terapéutico , Adulto , Anciano , Andrógenos/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Quimioterapia Combinada , Femenino , Humanos , Mastectomía , Persona de Mediana Edad , Tiotepa/administración & dosificación , Factores de Tiempo
20.
Clin Radiol ; 30(2): 139-47, 1979 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-86404

RESUMEN

Estracyt, a conjugate of an alkylating agent with an oestrogenic sterol, was given in a dose of 420 mg daily to a group of 44 postmenopausal patients with very advanced breast carcinoma. Thirty-eight of these were in relapse following chemotherapy and 32 had evidence of distant metastases. Seventeen patients had an objective response and marked or complete alleviation of symptoms, four others had a useful symptomatic response but no beneficial effect was observed in the remainder. Three who had shown no response to previous oestrogen therapy also failed to respond to Estracyt as did all nine patients with hepatic metastases. Oestrogen receptor status and age within the postmenopausal group seemed to have no bearing on the result. Side-effects were minimal with nausea in 18 patients but in only two did this necessitate withdrawal of the drug. Bone marrow depression did not occur. Changes in acute-phase reactant proteins suggested that part of the Estracyt was de-esterified in the liver liberating oestrone but the low incidence of vaginal haemorrhage and the recalcification of bony metastases suggested that on the whole Estracyt behaves as an anti-oestrogen as well as an antimitotic.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Anciano , Neoplasias de la Mama/análisis , Estramustina/uso terapéutico , Femenino , Humanos , Menopausia , Persona de Mediana Edad , Náusea/inducido químicamente , Metástasis de la Neoplasia , Cuidados Paliativos , Receptores de Estrógenos/análisis , Factores de Tiempo
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