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1.
J Anim Sci ; 96(3): 964-974, 2018 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-29401268

RESUMEN

Dairy slurry is used commonly as an animal-sourced fertilizer in agronomic production. However, residual effects of slurry application on intake and digestibility of alfalfa (Medicago sativa L.) silage from subsequent harvests are not well known. The objective of this study was to determine if moisture concentration of alfalfa silage and timing of dairy slurry application relative to subsequent harvest affected intake and digestibility by sheep. Katahdin crossbred ewes (n = 18; 48 ± 5.3 kg) in mid-gestation were stratified by BW and allocated randomly in each of two periods to one of six treatments arranged in a two × three factorial arrangement. Treatments consisted of recommended (RM; 46.8%) or low (LM; 39.7%) moisture at baling after either no slurry application (NS), slurry application to stubble immediately after removal of the previous cutting (S0), or slurry application 14 d after removal of the previous cutting (S14). Silages were chopped through a commercial straw chopper, packed into plastic trash cans, and then offered to ewes within 4 d of chopping. Period 1 of the intake and digestion study consisted of a 14-d adaptation followed by a 7-d fecal collection period. Period 2 followed period 1 after a 4-d rest and consisted of an 11-d adaptation followed by 7 d of fecal collection. Ewes were housed individually in 1.4 × 4.3-m pens equipped with rubber mat flooring. Feces were swept from the floor twice daily, weighed, and dried at 50 °C. Ewes had ad libitum access to water and were offered chopped silage for a minimum of 10% refusal (DM). Blood samples were collected immediately prior to feeding, and 4 and 8 h after feeding on the day prior to the end of each period. Organic matter intake (g/kg BW) and OM digestibility tended (P < 0.10) to be, and digestible OM intake (g/kg BW) was reduced by slurry application. Lymphocytes (% of total white blood cells) were greater (P < 0.05) from LM vs. RM and from NS vs. S0 and S14. Red blood cell concentrations were greater (P < 0.05) from S14 vs. S0 and from S0 and S14 vs. NS. Serum urea N concentrations did not differ (P > 0.17) across treatments. Therefore, moisture concentration of alfalfa silage within the range used in this study may not affect voluntary intake or digestibility, but slurry application may have an effect on digestible OM intake. Also, moisture concentration of alfalfa silage and time of dairy slurry application may affect specific blood hemograms.


Asunto(s)
Fertilizantes/análisis , Medicago sativa , Ovinos/fisiología , Ensilaje/análisis , Animales , Nitrógeno de la Urea Sanguínea , Dieta/veterinaria , Digestión , Heces , Femenino , Fermentación , Fertilizantes/efectos adversos , Estiércol , Distribución Aleatoria
2.
J Phys Chem Lett ; 9(4): 717-723, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-29365257

RESUMEN

The behavior of composite nanostructures depends on both size and elemental composition. Accordingly, concurrent control of size, shape, and composition of nanoparticles is key to tuning their functionality. In typical core-shell nanoparticles, the high degree of symmetry during shell formation results in fully encapsulated cores with severed access to the surroundings. We commingle light parameters (wavelength, intensity, and pulse duration) with the physical properties of nanoparticles (size, shape, and composition) to form hitherto unrealized core-vest composite nanostructures (CVNs). Unlike typical core-shells, the plasmonic core of the resulting CVNs selectively maintains physical access to its surrounding. Tunable variations in local temperature profiles ≳50 °C are plasmonically induced over starburst-shaped nanoparticles as small as 50-100 nm. These temperature variations result in CVNs where the shell coverage mirrors the temperature variations. The precision thus offered individually tailors access pathways of the core and the shell.

3.
J Anim Sci ; 94(12): 4985-4992, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28046149

RESUMEN

Bermudagrass ( L.) is a familiar forage in the equine industry and teff () is gaining popularity as well. However, it is unclear if the application of poultry litter as a fertilizer affects palatability of these forages in horses. Therefore, the objective of this study was to determine if forage species and timing of litter application as a fertilizer has an effect on preference by horses. Hay treatments were arranged in a 2 × 3 factorial treatment arrangement consisting of teff and bermudagrass harvested after no poultry litter application (NL), poultry litter applied to stubble immediately after removal of the previous cutting (L0), or poultry litter applied 14 d after the previous cutting (L14). Mature, stock-type geldings ( = 5; 480 ± 52.9 kg) were used in this study arranged as a balanced incomplete block design. Horses were offered different combinations of 4 of the 6 total forages daily for 3 d in each of 3 evaluation periods that immediately followed a 10-d adaptation period. Each forage was offered at half of the total daily DMI as measured during the last 5 d of the 10-d adaptation period to encourage selection among the 4 forages. Each hay offered was randomly allocated to a corner and suspended in hay nets over muck buckets in the corners of each stall. Horses were individually housed in 3.6- by 3.6-m indoor stalls with sand bedding and access to 3.6- by 7.6-m outdoor runs. Along with hay, horses were offered oats twice daily at 0.125% of BW at each feeding. Dry matter intake was greater ( < 0.01) for bermudagrass than for teff and for NL and L0 treatments compared with L14 treatments. Horses spent more ( < 0.01) time consuming bermudagrass compared with teff. However, there were no differences ( ≥ 0.25) in time spent consuming hay across litter treatments. Therefore, horses may prefer bermudagrass to teff and later application of poultry litter may affect voluntary intake by horses. However, all forages were mature, which may have impacted total intake and preference.


Asunto(s)
Alimentación Animal/análisis , Cynodon/química , Caballos/fisiología , Animales , Dieta/veterinaria , Eragrostis , Fertilizantes , Masculino , Estiércol , Aves de Corral , Factores de Tiempo
4.
Org Lett ; 4(20): 3403-6, 2002 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-12323029

RESUMEN

A series of per-6-substituted cyclodextrin derivatives was synthesized as synthetic host molecules for rocuronium, a steroidal muscle relaxant. By forming host-guest complexes with rocuronium, these cyclodextrin derivatives reverse the muscle relaxation induced by rocuronium in vitro and in vivo. The isothermal microcalorimetry data are consistent with the biological data supporting the encapsulation mechanism of action. Binary and biphasic complexes are reported with NMR experiments clearly showing free and bound rocuronium. [structure: see text]


Asunto(s)
Androstanoles/química , Ciclodextrinas/química , Ciclodextrinas/síntesis química , Fármacos Neuromusculares/química , gamma-Ciclodextrinas , Androstanoles/antagonistas & inhibidores , Androstanoles/síntesis química , Androstanoles/farmacología , Animales , Ciclodextrinas/farmacología , Cobayas , Espectroscopía de Resonancia Magnética , Conformación Molecular , Estructura Molecular , Fármacos Neuromusculares/antagonistas & inhibidores , Fármacos Neuromusculares/síntesis química , Fármacos Neuromusculares/farmacología , Rocuronio
5.
J Comp Pathol ; 125(1): 64-70, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11437518

RESUMEN

Bovine brain tissue samples from 625 UK cattle, clinically suspected as bovine spongiform encephalopathy (BSE) cases, were used in a blind analysis to assess a rapid Western immunoblotting technique (Prionics Check; Prionics AG, Zurich), which detects bovine disease-specific protease-resistant prion protein (PrP(Sc)). By means of statutory histopathological examination, 599 of the 625 cattle were confirmed as BSE cases by the demonstration of spongiform encephalopathy, the remaining 26 being classified as negative. Duplicate samples from the same animals were also examined by electron microscopy for the presence of abnormal brain fibrils (scrapie-associated fibrils; SAFs). The Prionics technique showed a high sensitivity, particularly when compared with the fibril detection test; the detection rates were 99.3% and 92.0% respectively, with histopathology being used as the "gold standard". The false negative results by the Prionics test were possibly related to the sampling procedure. Analysis of 50 BSE-positive samples revealed similar glycoprofiles, the majority of PrP(Sc)isoforms being di-glycosylated protein. The Prionics test also detected PrP(Sc)in the four brain samples from the 26 histopathologically negative animals, apparently reducing the specificity of the test to 84.6%; however, confirmatory positive results in these samples were obtained by demonstrating SAF or by immunohistochemical examination, or both. It was concluded that the Prionics test detected PrP(Sc)in a small percentage (0.64%) of clinically suspected BSE cases showing no spongiform change. Since January 2000, the Prionics Western blot test has been introduced as one of the statutory tests for the diagnosis of clinically suspected BSE and scrapie cases in the UK.


Asunto(s)
Western Blotting/veterinaria , Química Encefálica , Encefalopatía Espongiforme Bovina/diagnóstico , Proteína PrP 27-30/análisis , Animales , Western Blotting/métodos , Bovinos , Encefalopatía Espongiforme Bovina/epidemiología , Encefalopatía Espongiforme Bovina/virología , Inmunohistoquímica/veterinaria , Microscopía Electrónica/veterinaria , Proteína PrP 27-30/ultraestructura , Sensibilidad y Especificidad , Método Simple Ciego , Reino Unido/epidemiología
6.
J Med Chem ; 43(25): 4822-33, 2000 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-11123992

RESUMEN

Herein we describe the synthesis of novel di- and tripeptide derivatives with two quaternary nitrogen groups attached and the biological testing of these compounds for neuromuscular blocking (NMB) activity in vitro and in vivo. The short peptide scaffold was selected because it offers potential for desired distance between the two pharmacophoric quaternary nitrogen groups, short duration of action, straightforward synthesis, and compatibility with an injectable formulation. From a small series of compounds 20c,e are identified as effective non-depolarizing NMB agents in vitro and in vivo in anesthetized cats and Rhesus monkeys with potencies similar to those of the clinical reference compounds rocuronium (4) and suxamethonium (2) (monkey ED(90) = 0.68, 0.23, 0.16, 5.04 micromol/kg, respectively). These new peptide derivatives 20c,e have similar potency and onset time but longer duration and slower recovery than the clinically used reference compounds. The structure-activity relationships described for this chemical series lead to the conclusion that the di- or tripeptide fragment can be regarded as an alternative template to the steroid or aliphatic ester of previously reported NMBs and within this tripeptide-derived series clog P correlates well with in vitro NMB activity.


Asunto(s)
Aminas/síntesis química , Dipéptidos/síntesis química , Fármacos Neuromusculares no Despolarizantes/síntesis química , Oligopéptidos/síntesis química , Compuestos Onio/síntesis química , Aminas/química , Aminas/farmacología , Animales , Gatos , Pollos , Dipéptidos/química , Dipéptidos/farmacología , Electrofisiología , Femenino , Técnicas In Vitro , Macaca mulatta , Masculino , Contracción Muscular , Unión Neuromuscular/efectos de los fármacos , Unión Neuromuscular/fisiología , Fármacos Neuromusculares no Despolarizantes/química , Fármacos Neuromusculares no Despolarizantes/farmacología , Oligopéptidos/química , Oligopéptidos/farmacología , Compuestos Onio/química , Compuestos Onio/farmacología , Relación Estructura-Actividad
7.
J Med Chem ; 43(22): 4118-25, 2000 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-11063608

RESUMEN

Various cyclic ether and other 3 alpha-hydroxyandrostane derivatives bearing a conformationally constrained hydrogen-bonding moiety were prepared. Their anesthetic potency and their binding affinity for GABA(A) receptors, measured by intravenous administration to mice and inhibition of [(35)S]TBPS binding to rat whole brain membranes, were compared with that of known anesthetic 3 alpha-hydroxypregnan-20-ones. Synthetic steroids with similar in vitro and in vivo activities to the endogenous 3 alpha-hydroxypregnan-20-ones all had an ether oxygen on the beta-face of the steroid D-ring. These results suggest that for optimal GABA(A) receptor modulation, the hydrogen bond-accepting substituent should be near perpendicular to the plane of the D-ring on the beta-face of the steroid.


Asunto(s)
Androstanoles/síntesis química , Anestésicos/síntesis química , Moduladores del GABA/síntesis química , Receptores de GABA-A/efectos de los fármacos , Androstanoles/química , Androstanoles/farmacología , Anestésicos/química , Anestésicos/farmacología , Animales , Encéfalo/metabolismo , Moduladores del GABA/química , Moduladores del GABA/farmacología , Enlace de Hidrógeno , Técnicas In Vitro , Inyecciones Intravenosas , Ratones , Modelos Moleculares , Ensayo de Unión Radioligante , Ratas , Receptores de GABA-A/metabolismo , Relación Estructura-Actividad
8.
J Cancer Educ ; 15(4): 228-31, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11199241

RESUMEN

BACKGROUND: The purpose of the study was to analyze the effectiveness of a one-hour educational intervention to increase knowledge about and improve attitudes towards breast self-examination (BSE) and early cancer detection among adolescent girls. METHODS: The sample used in this quasi-experimental study was selected from schools participating in an education program provided by a regional health education center. The instrument and scales used in the study were developed and pilot-tested for reliability and validity in the area schools prior to the start of the study. The sample consisted of 137 adolescent girls who provided consent forms and participated in the intervention. The comparison group, which consisted of students attending the same schools, was scheduled to receive the intervention at a later date. RESULTS AND CONCLUSIONS: Findings suggest that a one-hour lesson can improve knowledge and attitudes of adolescent girls with respect to BSE and early cancer detection. Suggestions for further research are discussed.


Asunto(s)
Neoplasias de la Mama/prevención & control , Autoexamen de Mamas , Educación en Salud , Conocimientos, Actitudes y Práctica en Salud , Adolescente , Niño , Femenino , Humanos , Indiana , Análisis Multivariante , Servicios de Salud Escolar
9.
J Biol Chem ; 274(14): 9871-80, 1999 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-10092679

RESUMEN

The amino acid sequence LLVRGRTLVV, which is probably located in a strand-turn-strand structure, has been identified as a protein destruction signal in the rapidly degraded encephalomyocarditis virus 3C protease. Mutations within this sequence reduced the susceptibility of the 3C protease toward ubiquitination and degradation in rabbit reticulocyte lysate. This signal is transferable, since poliovirus 3C protease, which is a poor ubiquitin-mediated proteolytic system substrate, was found to be ubiquitinated and degraded when the signal sequence was either generated at an internal location in the protein or fused to the N terminus. An evaluation of the behavior of 3C protease proteins containing mutations in the signal region indicates that considerable variability in the primary structure is tolerated, although the conservation of certain features appears to be required for signal function. Two E3 ubiquitin-protein ligases that recognize the encephalomyocarditis virus 3C protease as a substrate were also partially purified. One of these was identified as the previously described E3alpha, and this was shown to require the destruction signal sequence to catalyze efficiently the ubiquitination of the 3C protease. The other is a Ubc5-dependent E3 that appears to recognize a different, unidentified feature of the 3C protease.


Asunto(s)
Cisteína Endopeptidasas/química , Virus de la Encefalomiocarditis/enzimología , Proteínas Virales , Proteasas Virales 3C , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Cisteína Endopeptidasas/genética , Cisteína Endopeptidasas/metabolismo , Ligasas/genética , Ligasas/metabolismo , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Conejos , Proteínas Recombinantes de Fusión/metabolismo , Relación Estructura-Actividad , Ubiquitina-Proteína Ligasas
10.
J Community Health ; 23(5): 359-70, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9793833

RESUMEN

A random sample of Pharmacists in Indiana was selected and surveyed regarding their thoughts and comments on the sale of tobacco and alcoholic products by pharmacies. A total of 212 pharmacists provided written responses to an open-ended question. The replies were then synthesized into major themes. The majority of comments categorized revealed strong opposition to pharmacies selling tobacco and alcohol products. The most frequently occurring message regarding the sale of these products by pharmacies was that it goes against the pharmacist's role as a professional health care provider and may harm their image. For some pharmacists, this issue posed a moral dilemma between caring for patient safety and the economic incentives provided by the sale of tobacco and alcohol. Based on these findings, a follow-up phone survey was conducted to solicit suggestions from pharmacists on how to advocate against the sale of tobacco and alcohol by pharmacies. The majority of pharmacists strongly recommended that they need to do more among themselves and within their store environment, rather than have regulations imposed on pharmacies when it comes to limiting the sale of these products.


Asunto(s)
Bebidas Alcohólicas , Actitud del Personal de Salud , Comercialización de los Servicios de Salud , Nicotiana , Farmacias , Farmacéuticos/psicología , Plantas Tóxicas , Adulto , Anciano , Femenino , Promoción de la Salud , Humanos , Indiana , Perfil Laboral , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
11.
Hypertension ; 32(2): 331-7, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9719063

RESUMEN

Superoxide radical (O2-) is ubiquitously critical to the bioactivity of endothelial nitric oxide. In angiotensin-dependent hypertension, vascular O2- levels rise and impede endothelium/nitric oxide-dependent vascular relaxation. We have reported that the major O2- source in the rabbit aorta is adventitial fibroblast phagocyte-like NADPH oxidase and shown that angiotensin (Ang) II treatment of adventitial fibroblasts causes a concentration-dependent increase in particulate NADPH-dependent O2-. From cultured rabbit aortic adventitial fibroblasts treated or not treated with Ang II, we prepared particulate fractions and measured lucigenin-enhanced chemiluminescence. Because [Sar1,Thr8]-Ang II, a generalized antagonist of Ang II and plausible inhibitor of the conversion of Ang II, reversed Ang II (10 nmol/L)-induced NADH- and NADPH-dependent O2- to basal levels, we tested the effect of the inhibitor of aminopeptidase N, amastatin (10 micromol/L), and found no effect on Ang II-stimulated O2-. Ang(1-7), Ang III, and Ang IV also were not effective in stimulating O2- levels at concentrations similar to those of Ang II. Kinetic analysis showed a rise in NADPH oxidase O2- production in response to Ang II, which peaks at 3 hours and returns to basal levels by 16 hours. p67phox, a cytosolic factor, appears to be affected at both the level of transcription and protein synthesis because actinomycin and cycloheximide individually inhibited the observed effect. A partial sequence of p67phox was recovered by reverse transcriptase from mRNA harvested from cultured rabbit aortic adventitial fibroblasts. Furthermore, the p67phox mRNA transcript in aortic fibroblasts is induced by Ang II before the peak of NADPH oxidase by Northern analysis and ribonuclease protection assays. These data suggest that Ang II stimulates NAD(P)H oxidase O2- generation in fibroblasts of aortic adventitia via transcriptional activation of p67phox. These data also provide preliminary evidence for the regulation of factors of the NADPH oxidase and potentially provide a novel means by which to abrogate the development of O2(-)-dependent hypertension.


Asunto(s)
Angiotensina II/farmacología , Aorta/metabolismo , NADPH Oxidasas/biosíntesis , Fosfoproteínas/biosíntesis , Vasoconstrictores/farmacología , Secuencia de Aminoácidos , Animales , Células Cultivadas , Fibroblastos/metabolismo , Datos de Secuencia Molecular , ARN Mensajero/biosíntesis , Conejos
12.
J Comp Pathol ; 118(1): 41-9, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9500237

RESUMEN

Detergent- and proteinase K-treated extracts of grey matter were prepared from four regions of the brains of 106 sheep with scrapie, diagnosed clinically and by the demonstration of spongiform encephalopathy. The extracts were examined by electron microscopy for the presence of scrapie-associated fibrils and by Western immunoblotting for the disease-specific abnormal prion protein (PrPSc). As a diagnostic method, Western immunoblotting proved to be more sensitive than electron microscopy, the detection rates in the 106 sheep being 97 and 91% respectively (medulla), 99 and 76% (cerebellum), 95 and 88% (frontal cerebral cortex) and 93 and 61% (occipital cerebral cortex). Neither fibrils nor PrPSc could be detected in comparable brain extracts from 25 control sheep which had shown no clinical or histopathological evidence of scrapie.


Asunto(s)
Western Blotting/veterinaria , Proteína PrP 27-30/análisis , Scrapie/patología , Animales , Cerebelo/química , Cerebelo/ultraestructura , Microscopía Electrónica , Proteína PrP 27-30/ultraestructura , Enfermedades por Prión/metabolismo , Enfermedades por Prión/patología , Enfermedades por Prión/veterinaria , Scrapie/diagnóstico , Scrapie/metabolismo , Ovinos
13.
Proc Natl Acad Sci U S A ; 94(26): 14483-8, 1997 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-9405639

RESUMEN

Superoxide anion (O2-) plays a key role in the endogenous suppression of endothelium-derived nitric oxide (NO) bioactivity and has been implicated in the development of hypertension. In previous studies, we found that O2- is produced predominantly in the adventitia of isolated rabbit aorta and acts as a barrier to NO. In the present studies, we characterize the enzyme responsible for O2- production in the adventitia and show that this enzyme is a constitutively active NADPH oxidase with similar composition as the phagocyte NADPH oxidase. Constitutive O2--generating activity was localized to aortic adventitial fibroblasts and was enhanced by the potent vasoconstrictor angiotensin II. Immunohistochemistry of aortic sections demonstrated the presence of p22(phox), gp91(phox), p47(phox), and p67(phox) localized exclusively in rabbit aortic adventitia, coincident with the site of staining for O2- production. Furthermore, immunodepletion of p67(phox) from adventitial fibroblast particulates resulted in the loss of NADPH oxidase activity, which could be restored by the addition of recombinant p67(phox). Further study into the regulation of this adventitial source of O2- is important in elucidating the mechanisms regulating the bioactivity of NO and may contribute to our understanding of the pathogenesis of hypertension.


Asunto(s)
Angiotensina II/farmacología , Aorta/metabolismo , Proteínas de Transporte de Membrana , NADPH Oxidasas/metabolismo , Fagocitos/metabolismo , Vasoconstrictores/farmacología , Animales , Aorta/citología , Células Cultivadas , Inmunohistoquímica , NADPH Deshidrogenasa/metabolismo , Fosfoproteínas/metabolismo , Conejos
14.
Am Ann Deaf ; 140(5): 410-4, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8585511

RESUMEN

The purpose of the present study was to determine the extent to which comprehensive (K-12) school health education was required. Permission to modify survey questions from the American School Health Association and the National School Board Association was obtained. As part of a larger study, ten items of the questionnaire were used to identify the status of health education in residential schools for the deaf. The questionnaire was mailed to institutions listed in a Reference Issue of the American Annals of the Deaf. Twenty-five institutions responded and results were tabulated using descriptive statistics. Twenty-two (88%) of the responding schools indicated a comprehensive health instruction program was in place, with 60% of respondents had specified time requirement for health instruction. The majority of responding institutions reported that teachers responsible for teaching the health curriculum to the deaf were not required to be certified in health education. Health education certification for educators of the deaf would assist in upgrading the quality of health education in residential schools for the deaf.


Asunto(s)
Curriculum , Sordera , Educación en Salud , Instituciones Residenciales , Instituciones Académicas , Humanos
17.
Plant Cell ; 3(9): 935-951, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12324623

RESUMEN

A plant embryo consists of an embryonic axis, which eventually grows into the adult body, and one or two nutritive structures, the cotyledons. In the grasses embryo morphogenesis can be divided into three periods: during the first the embryo is regionalized into an embryo proper and suspensor, during the second the embryonic axis is established, and during the third vegetative structures are elaborated. Maize, with its well-characterized embryo-genesis, powerful genetics, and transposon tagging stocks, offers an attractive system for mutational analysis of these events. We have isolated 51 embryo-specific (emb) mutations from active Robertson's Mutator maize stocks. These are single-gene recessive lethals that represent at least 45 independent mutation events. Each of the 25 mutations was located to a chromosome arm using a B-A translocation set that uncovers approximately 40% of the genome; the same test failed to locate 20 others. The embryo phenotype of 27 mutations was characterized by examining mature mutant embryos in fresh dissection: the various emb mutations differ in phenotype and each is consistent in its expression. All 27 mutations result in retarded embryos that are morphologically abnormal. Nine mutants are blocked during the first period; 10 mutants are blocked during the second period; and eight mutants are blocked during the third period. Based on both the genetic and developmental data, it is likely that there are many loci that can mutate to give the emb phenotype and that these genes are crucial to the morphogenesis of the embryo.

19.
Genetics ; 120(1): 279-90, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17246478

RESUMEN

We have examined the effects on embryonic and gametophytic development of two nonallelic defective-kernel mutants of maize. Earlier studies indicated that both mutants are abnormal in embryonic morphogenesis as well as in the formation of their endosperm. Mutant rgh*-1210 embryos depart from the normal embryogenic pathway at the proembryo and transition stage, by developing meristematic lobes and losing bilateral symmetry. They continue growth as irregular cell masses that enlarge and become necrotic. Somatic embryos arising in rgh*-1210 callus cultures display the rgh*-1210 mutant phenotype. Mutant fl*-1253B embryos are variably blocked from the coleoptilar stage through stage 2. Following formation of the shoot apex in the mutant embryos the leaf primordia and tissues surrounding the embryonic axis continue growth and cell division, while the scutellum ceases development and becomes hypertrophied. Mutant fl*-1253B embryos are unable to germinate, either in mutant kernels or as immature embryos in culture, and the mutant scutellar tissue does not produce regenerable callus. Expression of the fl*-1253B locus during male gametophytic development is revealed by a marked reduction in pollen transmission as a result of mutant expression during the interval between meiosis and the initiation of pollen tube growth. In both mutants, there is considerable proliferation of the aleurone cells of the endosperm. Mutant expression of rgh*-1210 in the female gametophyte is revealed by the abnormal antipodal cells of the embryo sac. These results show that these two gene loci play unique and crucial roles in normal morphogenesis of the embryo. In addition, it is evident that both mutants are pleiotropic in affecting the development of the endosperm and gametophyte as well as the embryo. These pleiotropisms suggest some commonality in the gene regulation of development in these three tissues.

20.
J Antimicrob Chemother ; 21(2): 183-6, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3360681

RESUMEN

The effects of several quinolone compounds on mitogen-stimulation of normal human mononuclear leucocytes were studied. In these experiments, mononuclear leucocytes were obtained from heparinized whole blood of healthy young adult donors by Ficoll-hypaque sedimentation. The cells were cultured in the presence of both mitogen and various concentrations of the quinolone compounds. Control cultures (without the addition of the quinolones) were examined concurrently. Our data suggests that the quinolones tested, with the exception of rosoxacin (acrosoxacin) at a concentration of 2.5 mg/l, neither impair nor stimulate activation of lymphocytes by the mitogen phytohaemagglutinin (PHA) when used at the concentrations obtained during therapy.


Asunto(s)
4-Quinolonas , Fluoroquinolonas , Activación de Linfocitos/efectos de los fármacos , Quinolinas/efectos adversos , Quinolonas , Adulto , Antiinfecciosos/efectos adversos , Ciprofloxacina/efectos adversos , Ciprofloxacina/análogos & derivados , Humanos , Técnicas In Vitro , Norfloxacino/efectos adversos , Fitohemaglutininas/farmacología
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