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1.
Mitochondrial DNA B Resour ; 5(3): 3310-3312, 2020 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-33458148

RESUMEN

Here, we present the mitogenome of the blood feeding leech Haementeria acuecueyetzin (Hirudinida: Glossiphoniidae) based on specimens collected in Tabasco, Mexico. The circular genome is 14,985 bp in length, and consists of 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and an AT-rich control region. Phylogenetic analysis based on the 13 protein-coding genes and two rRNA genes places H. acuecueyetzin sister to H. officinalis within the family Glossiphoniidae. Mitochondrial gene order in H. acuecueyetzin is consistent with other members of Clitellata with no evidence of gene gain/loss, duplication, or rearrangement.

2.
J Parasitol ; 102(5): 553-555, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27391275

RESUMEN

Invertebrate-derived ingested DNA (iDNA) is quickly proving to be a valuable, non-invasive tool for monitoring vertebrate species of conservation concern. Using the DNA barcoding locus, we successfully identified both the blood-feeding leech Haementeria acuecueyetzin and its blood meal-the latter is shown to be derived from the Caribbean manatee, Trichechus manatus . DNA amplification was successful despite the fact that the specimen was fixed in Mezcal (a beverage distilled from agave). We report the first confirmed case of a leech feeding on a manatee, the first record of H. acuecueyetzin for the State of Chiapas and, to our knowledge, the first case of successful DNA amplification of a biological sample fixed in Mezcal other than the caterpillar "worms" more commonly found in that beverage.


Asunto(s)
Agave/parasitología , Código de Barras del ADN Taxonómico/veterinaria , Jugos de Frutas y Vegetales/parasitología , Sanguijuelas/clasificación , Trichechus/parasitología , Animales , Femenino , Fijadores , Sanguijuelas/genética , México , Filogenia , Trichechus/sangre , Indias Occidentales
3.
J Gen Psychol ; 135(1): 37-53, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18318407

RESUMEN

The authors examined pre- and postpartum open-field (OF) behavior and maternal responsiveness in mice that they bidirectionally selected for OF thigmotaxis. The authors tested 40 female mice under 3 conditions: prepartum OF, postpartum OF, and a pup retrieval test. In both OF conditions, the high OF thigmotaxis (HOFT) mice were more thigmotactic but explored and reared less than the low OF thigmotaxis (LOFT) mice, indicating that the HOFT mice were more emotional. In the postpartum condition, the HOFT mothers also defecated more and ambulated less than the LOFT mothers. The increase in grooming after parturition was more conspicuous among the LOFT mothers than among the HOFT mothers. The LOFT mothers were also more attracted to their pups in the OF, but the retrieval test did not show any substantial line differences. The results suggested that the line difference in emotionality was more pronounced during lactation than during pregnancy, although parturition exerted no effect on thigmotaxis.


Asunto(s)
Nivel de Alerta/genética , Conducta Exploratoria , Conducta Materna/psicología , Preñez/genética , Preñez/psicología , Propiocepción/genética , Selección Genética , Animales , Conducta Excretoria Animal , Emociones , Femenino , Aseo Animal , Técnicas In Vitro , Ratones , Actividad Motora/genética , Embarazo , Tiempo de Reacción/genética , Especificidad de la Especie
4.
Behav Processes ; 72(1): 23-31, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16386379

RESUMEN

We examined: (a) the response to bidirectional selection for open-field (OF) thigmotaxis in mice for 23 generations and (b) the effects of repeated exposure (during 5 days) on different OF behaviors in the selectively bred high OF thigmotaxis (HOFT) and low OF thigmotaxis (LOFT) mice. A total of 2049 mice were used in the study. Prior to the testing in the selection experiment, the mice were exposed to the OF apparatus for approximately 2 min on each of 4 consecutive days. Thus, the selection was based on the scores registered on the 5th day after the four habituation periods. The HOFT mice were more thigmotactic than the LOFT mice in almost each generation. The HOFT mice also tended to rear less than the LOFT mice, which was explained by the inverse relationship between emotionality and exploratory tendencies. The lines did not generally differ in ambulation. Sex differences were found in thigmotaxis, ambulation, and rearing. In the repeated exposure experiment, the development of nine different OF behaviors across the 5 days of testing was addressed. Both lines ambulated, explored, and reared most on the 1st, 4th, and 5th days. Grooming and radial latency decreased and thigmotaxis increased linearly across the testing days. Line differences were found in ambulation, exploration, grooming, and rearing, while sex differences were manifested in ambulation and exploration. The line difference in thigmotaxis was evident only on the 5th day. Temporal changes were partially at variance with the general assumptions. OF thigmotaxis was found to be a powerful characteristic for producing two diverging lines of mice.


Asunto(s)
Reacción de Prevención , Conducta Exploratoria , Miedo , Habituación Psicofisiológica , Memoria a Corto Plazo , Selección Genética , Animales , Nivel de Alerta/genética , Emociones , Femenino , Habituación Psicofisiológica/genética , Masculino , Ratones , Actividad Motora/genética , Fenotipo , Tiempo de Reacción/genética , Estadística como Asunto
5.
J Psychosom Obstet Gynaecol ; 26(3): 193-204, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16295517

RESUMEN

Sixty-five women (aged 32 - 54 yrs) were assessed at 2 months before to 8 months after total abdominal hysterectomy on four separate occasions. Beck's Depression Inventory (BDI), Taylor's Manifest Anxiety Scale (TMAS), the Buss-Durkee Hostility Inventory (BDHI), Measurement of Masculinity-Femininity (MF), Likert scales and semantic differentials for psychological, somatic and sexual factors varied as assessment tools. High-dysphoric and low-dysphoric women were compared with regard to hysterectomy outcomes. Married nulliparae suffered from enhanced depression post-surgery. Pre-surgery anxiety, back pain and lack of dyspareunia contributed to post-surgery anxiety. Pre-surgery anxiety was related to life crises. Pre- and post-surgery hostility occurred in conjunction with poor sexual gratification. Post-hysterectomy health improved, but quality of sexual relationship was impaired. Partner support and knowledge counteracted hysterectomy aftermath. Post-hysterectomy symptoms constituted a continuum to pre-surgery signs of depression, anxiety or hostility.


Asunto(s)
Ansiedad/psicología , Depresión/psicología , Hostilidad , Histerectomía/psicología , Complicaciones Posoperatorias/psicología , Adulto , Coito/psicología , Femenino , Estudios de Seguimiento , Identidad de Género , Humanos , Acontecimientos que Cambian la Vida , Persona de Mediana Edad , Orgasmo , Inventario de Personalidad , Factores de Riesgo
6.
J Gen Psychol ; 132(2): 187-204, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15871300

RESUMEN

In 2 experiments, the authors examined 69 mice selectively bred for high or low levels of open-field (OF) thigmotactic behavior (high open-field thigmotaxis [HOFT] and low open-field thigmotaxis [LOFT], respectively). They found that the strains differed in defecation during the 60-min exposure to the OF. Furthermore, the strains differed with regard to their life spans: The more thigmotactic HOFT mice lived longer than the LOFT mice. The strains were not differentiated by food intake or excretion. The strain difference in thigmotaxis was not age dependent, and it persisted in the home-cage condition as well. Neither the location (center or wall) of the starting point nor the shape (circular or square) of the OF arena affected the difference in wall-seeking behavior between the two strains. The authors concluded that the difference in thigmotaxis (or emotionality) between the HOFT and LOFT mice is a stable and robust feature of these animals.


Asunto(s)
Cruzamiento , Selección Genética , Factores de Edad , Animales , Conducta Animal/fisiología , Femenino , Masculino , Ratones
7.
Scand J Psychol ; 46(1): 21-9, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15660630

RESUMEN

The main purpose of this research was to investigate whether the difference in open-field (OF) thigmotaxis between mice selectively bred for high and low levels of wall-seeking behavior originated from genetic or acquired sources. Unfostered, infostered, and crossfostered mice were compared in two experiments in which the effects of strain, sex, and fostering on ambulation, defecation, exploration, grooming, latency to move, radial latency, rearing, thigmotaxis, and urination were studied. These experiments revealed that OF thigmotaxis was unaffected by the foster condition and thus genetically determined. The selected strains of mice also diverged repeatedly with regard to exploration and rearing. The findings are in line with the previously described existence of an inverse relationship between emotionality and exploration.


Asunto(s)
Cruzamiento , Conducta Espacial , Crianza de Animales Domésticos , Animales , Animales Recién Nacidos , Conducta Animal , Defecación , Femenino , Masculino , Ratones , Distribución Aleatoria , Conducta Social , Aislamiento Social , Micción
8.
Cardiovasc Res ; 52(1): 136-42, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11557242

RESUMEN

OBJECTIVE: The effect of invasive treatment of renal artery stenosis on the use of antihypertensive medication, blood pressure, and morphology and function of resistance arteries was investigated in 14 renovascular hypertensive patients before and after treatment compared to normotensive controls. METHODS: Use of antihypertensive medication was calculated as defined daily doses (DDD). Resistance arteries were taken from gluteal subcutaneous biopsies and analyzed in a myograph. RESULTS: Prior to invasive treatment, blood pressure of the patients was elevated compared to normotensive controls. Six months after technically successful invasive treatment, patients were still hypertensive compared to time-matched controls. The use of antihypertensive medication was reduced from 4.4+/-0.7 DDD before invasive treatment to 3.0+/-0.6 DDD 6 months after treatment. Vascular structure of resistance arteries, expressed as media/lumen ratio (media thickness to diameter), was greater in patients before invasive treatment (10.7+/-1.0%) compared to normotensive controls (7.9+/-0.8%). Media/lumen ratio of resistance arteries was reduced to that of the controls 6 months after invasive treatment despite the remaining hypertension. The functional studies showed no difference in response to acetylcholine, adenosine, noradrenaline or angiotensin II between patients and controls before or after treatment. CONCLUSIONS: This study shows that hypertension and increased media/lumen ratio of resistance arteries prevail in renovascular hypertensive patients despite antihypertensive medication and that invasive treatment is of benefit as regards use of antihypertensive medication. The study provides the novel information that the remaining hypertension is not due to uncorrected media/lumen ratio of the resistance arteries.


Asunto(s)
Angioplastia de Balón , Hipertensión Renovascular/terapia , Arteria Renal/cirugía , Acetilcolina/farmacología , Adenosina/farmacología , Angiotensina II/farmacología , Antihipertensivos/uso terapéutico , Arterias , Estudios de Casos y Controles , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Hipertensión Renovascular/diagnóstico , Hipertensión Renovascular/tratamiento farmacológico , Técnicas In Vitro , Masculino , Persona de Mediana Edad , Músculo Liso Vascular/efectos de los fármacos , Norepinefrina/farmacología , Renina/sangre , Resultado del Tratamiento , Resistencia Vascular/efectos de los fármacos
9.
Percept Mot Skills ; 84(3 Pt 1): 911-4, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9172202

RESUMEN

Sex differences in strategies of coping with novel situations were studied in three strains of mice with regard to metabolism and open-field and maze activity as well as learning-induced adjustment. The 140 mice were selectively bred for high (Turku Aggressive [TA]) and low (Turku Nonaggressive [TNA]) levels of aggressiveness and originated from a Swiss albino stock normally distributed [N] for aggressiveness. The results indicated that TNA sex differences are more similar to those of the control N mice as compared to those of TA mice. In maze learning, however, the sex differences of TA mice are more in agreement with those of the N strain. Recordings of metabolism and open-field as well as maze activity were correlates of both gender and strain. Sex differences in learning-induced open-field coping behavior were unrelated to strain.


Asunto(s)
Agresión/psicología , Ratones Endogámicos/genética , Selección Genética , Adaptación Psicológica , Animales , Nivel de Alerta/genética , Conducta Animal , Femenino , Masculino , Ratones , Caracteres Sexuales
10.
J Immunol ; 157(1): 213-20, 1996 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-8683118

RESUMEN

Cytotoxic T lymphocytes recognize antigenic peptides presented by MHC class I molecules. The peptides are generated in the cytosol by proteasomes, and probably also other proteases, and are then translocated into the endoplasmic reticulum (ER) lumen. The transporters associated with Ag processing (TAP) are key molecules for transporting peptides from the cytosol to the lumen of the ER. Using semipermeabilized cells, TAP-dependent peptide translocation was demonstrated, and the selectivity of peptide translocation was based on the carboxyl-terminal amino acid of peptides. We have examined peptide binding proteins in the ER membrane and the selection of peptides for binding to TAP by using a panel of peptides of different sequences and carboxyl-termini as well as peptides containing D amino acids. Peptides bound to TAP molecules in the absence of ATP. The presence of ATP induced binding of peptides to two additional membrane proteins (58 and 43 kDa). The selection of peptides by TAP molecules was based on peptide sequence and the carboxyl-terminal amino acid. Peptides containing D amino acid did not bind to TAP molecules. Rat cim-a and -b selected peptides differently, and selection was not only dependent on the carboxyl-terminal residue of the peptide, but included an influence of the peptide sequence. The different off-rates after peptide binding to TAP, indicated a dual binding step of peptide to TAP. ATP regulated the off-rate of peptides at a high affinity binding step. Our results demonstrate that the binding of peptides to TAP molecules is specific and most likely involves a multiple step pathway.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/inmunología , Transportadoras de Casetes de Unión a ATP/metabolismo , Presentación de Antígeno , Oligopéptidos/inmunología , Oligopéptidos/metabolismo , Transportadoras de Casetes de Unión a ATP/efectos de los fármacos , Adenosina Trifosfato/farmacología , Alelos , Secuencia de Aminoácidos , Animales , Presentación de Antígeno/efectos de los fármacos , Azidas/química , Unión Competitiva/inmunología , Reactivos de Enlaces Cruzados , Humanos , Membranas Intracelulares/química , Complejo Mayor de Histocompatibilidad/efectos de los fármacos , Complejo Mayor de Histocompatibilidad/inmunología , Microsomas Hepáticos/química , Datos de Secuencia Molecular , Oligopéptidos/química , Unión Proteica/inmunología , Conformación Proteica , Ratas , Ratas Endogámicas Lew , Ratas Endogámicas SHR , Succinimidas/química
11.
Int Immunol ; 8(4): 467-78, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8671633

RESUMEN

We have studied the degradation of a set of long peptides (9-30 amino acids) from the nucleoprotein of influenza A. In common for all these peptides is the core sequence NH2-Ser-Arg-Tyr-Trp-Ala-Ile-Arg-Thr-Arg-COOH, NP383-391, known as an antigenic peptide specific for the HLA-B27 class I antigen. We show that this peptide is generated by enriched cytosolic proteasomes of two sizes, 20S and 12S. The 12S proteasome is the precursor, the preproteasome, to the 20S mature proteasome as shown by pulse-chase experiment and is most likely responsible for the proteolytic activity in the 12S region. Cleavage at the N-terminus is distinct and restricted to residue 383, independent of the N-terminal extension of the peptide. The C-terminus is generated via cleavage at three sites. Intermediate and final peptide products were identified by mass spectrometry. Finally, we show that the NP383-391 peptide generated by proteasomes in vitro is functional inasmuch as it possesses the ability to stimulate assembly of in vitro translated HLA-B27 antigens.


Asunto(s)
Antígeno HLA-B27/química , Antígeno HLA-B27/fisiología , Virus de la Influenza A/química , Virus de la Influenza A/inmunología , Linfocitos/química , Microsomas/inmunología , Microsomas/metabolismo , Nucleoproteínas/biosíntesis , Nucleoproteínas/inmunología , Nucleoproteínas/fisiología , Secuencia de Aminoácidos , Western Blotting , Células Cultivadas , Clonación Molecular , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Datos de Secuencia Molecular , Proteínas Virales/biosíntesis , Proteínas Virales/inmunología , Proteínas Virales/fisiología
12.
Eur J Pharmacol ; 274(1-3): 109-15, 1995 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-7768262

RESUMEN

The time course of action of amlodipine was compared to that of felodipine in rat mesenteric resistance arteries and aorta. Both amlodipine and felodipine caused a concentration-dependent relaxation of K(+)-depolarized resistance arteries: with amlodipine 3 x 10(-8) M and felodipine 10(-9) M, complete relaxation was reached after 40 min and 10 min, respectively. Furthermore, in resistance arteries, the time course of action of both drugs was shortest in vessels with the smallest diameter. In aorta, both drugs caused a marked relaxation of K(+)-induced tone, without reaching a maximal effect within 2 h. Recovery of K(+)-induced tone after both drugs was complete in resistance arteries, but not aorta, within 2 h. In resistance arteries exposed to K+ depolarization or noradrenaline, both drugs displayed the characteristics of 1,4-dihydropyridine Ca2+ channel antagonists. The results show that amlodipine was slower to have an effect than felodipine, but that both drugs acted fastest in the smallest arteries.


Asunto(s)
Amlodipino/farmacología , Aorta/efectos de los fármacos , Felodipino/farmacología , Arterias Mesentéricas/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Amlodipino/administración & dosificación , Análisis de Varianza , Animales , Aorta/metabolismo , Calcio/metabolismo , Bloqueadores de los Canales de Calcio/administración & dosificación , Bloqueadores de los Canales de Calcio/farmacología , Felodipino/administración & dosificación , Modelos Lineales , Masculino , Arterias Mesentéricas/metabolismo , Relajación Muscular/efectos de los fármacos , Potasio/farmacología , Ratas , Ratas Wistar , Programas Informáticos , Factores de Tiempo , Resistencia Vascular/efectos de los fármacos
13.
Exp Aging Res ; 19(3): 259-75, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8223826

RESUMEN

The effects of age and situation-specific experience on maze learning and learning-sensitive open-field parameters (OFP) in Swiss albino male mice were studied. We tested the mice longitudinally by means of repeated measures and in cross-section by taking independent samples between the ages of 1-16 months. Mice with situation-specific experience improved their performance up to the age of 11 months. For mice lacking prior experience there was a trend toward impaired performance with regard to error scores and running times with increasing age. The ages of 1, 8, and 10 months were most favorable for the occurrence of quantitative maze learning-sensitive OFP changes, and the ages of 1, 3, 4, 8, 9, 10, 12, and 13 months were most favorable for the appearance of qualitative changes. The effect of situation-specific experience was interpreted as indicative of decreased emotionality but increased reactivity to novel stimuli or enhanced territorial behavior at the age of 16 months.


Asunto(s)
Envejecimiento/psicología , Aprendizaje/fisiología , Envejecimiento/fisiología , Animales , Defecación , Emociones , Masculino , Ratones , Actividad Motora , Tacto , Micción
14.
Semin Immunol ; 5(2): 105-16, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8504215

RESUMEN

The MHC class I heavy chain and beta 2-microglobulin are cell surface proteins, and are synthesized on membrane bound ribosomes. They are co-translationally inserted into the endoplasmic reticulum (ER) membrane and assemble with antigenic peptides in the lumen of this compartment. These peptides are believed to be generated in the cytosol, and must be protected from degradation prior to translocation across the ER membrane. Putative peptide transporters (TAP1 and 2) belonging to the ABC transporter family of proteins, have been suggested to function in this process, and have been shown to be essential for MHC class I antigen assembly. The finding that peptides were translocated across the ER membrane in microsomes prepared from cells lacking the TAP genes has challenged this view. In this review we discuss the different events leading to correct assembly of MHC class I antigens. We suggest the TAP molecules to be part of a complex, which function to select peptides, protect them from degradation, and facilitate their translocation by targeting them to the ER membrane.


Asunto(s)
Antígenos de Histocompatibilidad Clase I/metabolismo , Animales , Transporte Biológico , Citosol/metabolismo , Retículo Endoplásmico/metabolismo , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Membranas Intracelulares/metabolismo , Biosíntesis de Proteínas
15.
Scand J Psychol ; 33(4): 378-84, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1287829

RESUMEN

Both male (n = 244) and female (n = 223) Swiss albino mice displayed a U-shaped pattern of thigmotaxis (wall-seeking) in a circular open-field (OF) before and after a daily maze-running. A significant increase of mice's tendency to occupy the inner partitions of the OF after the maze trial on the last three out of five days of training was observed. When factor analyzed, the variables indicating the wall-seeking behaviour of both sexes were divided into two factors interpreted as "spontaneous" in conjunction with the first three to four maze trials and as "learning-related thigmotactic behaviour" during the subsequent trials in the course of the learning process.


Asunto(s)
Nivel de Alerta , Aprendizaje Discriminativo , Conducta Exploratoria , Orientación , Medio Social , Animales , Miedo , Femenino , Masculino , Ratones , Actividad Motora , Solución de Problemas , Propiocepción , Factores Sexuales
16.
Scand J Psychol ; 33(2): 97-107, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1641611

RESUMEN

Maze training was shown to affect qualitative aspects of the learning-sensitive open-field (OF) ambulation in male Swiss albino mice. The changes in thigmotactic (wall-seeking) behaviour were most pronounced when significant signs of learning occurred, usually on the third day of training. Also daily changes in thigmotaxis from before to after training were found. Mice not subjected to maze training exhibited a different thigmotactic pattern of behaviour. The present series of experiments indicated that separate starting-points (centre or wall) influenced the thigmotactic behaviour as opposed to the shape of the OF (circular or square).


Asunto(s)
Nivel de Alerta , Aprendizaje Discriminativo , Recuerdo Mental , Actividad Motora , Orientación , Animales , Conducta Exploratoria , Miedo , Masculino , Ratones
17.
Percept Mot Skills ; 73(3 Pt 1): 811-24, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1792129

RESUMEN

Significant differences were observed in thigmotaxis, ambulation, and latency to move (time to start ambulating) between highly aggressive (TA) and low aggressive (TNA) male mice. The former displayed more thigmotaxis, ambulated more, and had a shorter latency to move than the TNA animals. Also they voided a greater number of urinary spots and defecated less than TNA. Further they were superior to the TNA mice in maze-learning capacity. The tendency to enter inner partitions of the field as well as total ambulation increased after learning by TA mice. The training toward nonaggressiveness of TA mice suppressed aggressive responses, thigmotaxis, and the number of urinary spots but enhanced defecation. All measures returned to their initial levels after one month of rest. The attacking behaviour of TA animals increased both thigmotaxis and ambulation.


Asunto(s)
Agresión/psicología , Aprendizaje Discriminativo , Conducta Exploratoria , Recuerdo Mental , Actividad Motora , Orientación , Animales , Masculino , Ratones , Ratones Endogámicos , Tiempo de Reacción , Medio Social
18.
J Cell Biol ; 115(4): 959-70, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1955465

RESUMEN

We have translated major histocompatibility complex (MHC) class I heavy chains and human beta 2-microglobulin in vitro in the presence of microsomal membranes and a peptide from the nucleoprotein of influenza A. This peptide stimulates assembly of HLA-B27 heavy chain and beta 2-microglobulin about fivefold. By modifying this peptide to contain biotin at its amino terminus, we could precipitate HLA-B27 heavy chains with immobilized streptavidin, thereby directly demonstrating class I heavy chain-peptide association under close to physiological conditions. The biotin-modified peptide stimulates assembly to the same extent as the unmodified peptide. Both peptides bind to the same site on the HLA-B27 molecule. Immediately after synthesis of the HLA-B27 heavy chain has been completed, it assembles with beta 2-microglobulin and peptide. These interactions occur in the lumen of the microsomes (endoplasmic reticulum), demonstrating that the peptide must cross the microsomal membrane in order to promote assembly. The transfer of peptide across the microsomal membrane is a rapid process, as peptide binding to heavy chain-beta 2-microglobulin complexes is observed in less than 1 min after addition of peptide. By using microsomes deficient of beta 2-microglobulin (from Daudi cells), we find a strict requirement of beta 2-microglobulin for detection of peptide interaction with the MHC class I heavy chain. Furthermore, we show that heavy chain interaction with beta 2-microglobulin is likely to precede peptide binding. Biotin-modified peptides are likely to become a valuable tool in studying MHC antigen interaction and assembly.


Asunto(s)
Antígeno HLA-B27/biosíntesis , Microsomas/metabolismo , Nucleoproteínas/metabolismo , Microglobulina beta-2/biosíntesis , Secuencia de Aminoácidos , Transporte Biológico , Biotina , Sistema Libre de Células , Técnicas de Cultivo , Retículo Endoplásmico/metabolismo , Antígenos de Histocompatibilidad Clase I/biosíntesis , Humanos , Membranas Intracelulares/metabolismo , Cinética , Datos de Secuencia Molecular , Péptidos/metabolismo , Biosíntesis de Proteínas
19.
Cell ; 67(2): 265-74, 1991 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-1913823

RESUMEN

We have translated the HLA-B27 heavy chain in vitro and studied its assembly with beta 2-microglobulin and peptide in microsomes from human cells. The assembly process requires ATP. However, the translocation of peptide across the endoplasmic reticulum (ER) membrane does not require ATP, and binding of biotinylated peptide to BiP, an ER luminal protein, occurs after ATP depletion. Proteinase K treatment of the microsomes does not block peptide translocation. Thus, ATP is required in the lumen of the ER for efficient assembly to occur. Microsomes prepared from Raji and T1 cells show similar levels of assembly, whereas assembly in T2 microsomes is 10-fold lower. This difference remains after peptide stimulation of assembly. The inefficient assembly in T2 microsomes is not due to impaired peptide translocation across the ER membrane, as no difference was found compared with microsomes from T1 cells. Instead, the defect seems to reside in the lumen of the ER.


Asunto(s)
Adenosina Trifosfato/metabolismo , Retículo Endoplásmico/metabolismo , Antígeno HLA-B27/metabolismo , Procesamiento Proteico-Postraduccional/fisiología , Microglobulina beta-2/metabolismo , Transporte Biológico Activo/fisiología , Biotina/metabolismo , Línea Celular , Sistema Libre de Células , Electroforesis en Gel de Poliacrilamida , Endopeptidasa K , Humanos , Virus de la Influenza A/metabolismo , Sustancias Macromoleculares , Microsomas/metabolismo , Nucleoproteínas/metabolismo , Biosíntesis de Proteínas/fisiología , Serina Endopeptidasas/metabolismo
20.
Psychol Rep ; 68(3 Pt 2): 1139-50, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1924614

RESUMEN

During the 11-yr. period of 1976 to 1986 leukemia or lymphoma treatment at the Children's Hospital, University of Helsinki was electively discontinued for the children in 90 different families. Of the 53 (59%) patients (mean age 6.4 yr. at diagnosis and 12.8 yr. at completion of questionnaires) who agreed to participate in the present study, 48 had acute lymphoblastic leukemia and five nonHodgkin lymphoma. Patients' and parents' impressions of the patients' psychological reactions during patients' prior chemotherapy were evaluated on parental and self-ratings. Also, knowledge of and presumed causes of the malignancy were studied. Patients' reactions of aggression, depression, eating disorders, hypersensitivity, phobic anxiety, death anxiety, and night terror were examined using factor analysis. Aggression, in the form of irritation and anger, was displayed more often by girls than by boys. Patients of families suffering from stress were prone to exhibit aggression in the form of mood changes, irritation, and anger. Patients with disease-related knowledge, as opposed to those less well informed, were less depressed. Discrepancies between parents' and patients' thoughts about the origin of the malignancy were noted.


Asunto(s)
Adaptación Psicológica , Agresión/psicología , Leucemia/psicología , Linfoma/psicología , Rol del Enfermo , Adolescente , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Niño , Femenino , Humanos , Leucemia/tratamiento farmacológico , Linfoma/tratamiento farmacológico , Masculino , Padres/psicología , Pacientes Desistentes del Tratamiento/psicología
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