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PUVA treatment of human keratinocytes suppresses the surface expression of intercellular adhesion molecule 1 (ICAM-1) and inhibits adherence of PHA-blasts in vitro.

To determine the basis of the therapeutic efficacy of Psoralens and UVA (PUVA) in inflammatory skin diseases, the effect of PUVA on the expression of cell adhesion molecules of keratinocytes was investigated in vitro. The addition of IFN-gamma and TNF-alpha to human keratinocytes in culture up-regulated the expression of ICAM-1 and HLA-DR on the cell surface. The cultured human keratinocytes were exposed to UVA light in the presence of 8-methoxypsoralen (PUVA). The ICAM-1 and HLA-DR surface molecules were stained by monoclonal antibodies, and the intensity of the resultant fluorescence was analyzed by FACS-can. PUVA treatment suppressed the expression of these cell surface molecules, with increasing UVA fluence. Moreover, PHA-blasts failed to adhere to PUVA treated keratinocytes. When keratinocytes were treated with PUVA prior to the addition of IFN-gamma and TNF-alpha, ICAM-1 and HLA-DR expression was suppressed. These results suggest that one of the therapeutic mechanisms of PUVA in inflammatory skin diseases is by inhibition of the adhesion of activated lymphocytes to keratinocytes due to suppression of cell surface molecules. It also suggests that PUVA may be useful as maintenance therapy for inflammatory skin diseases.

Adult↗

Organization of projections from the dorsomedial nucleus of the hypothalamus: a PHA-L study in the rat.

The axonal projections of the dorsomedial nucleus of the hypothalamus were investigated by using Phaseolous vulgaris-leucoagglutinin. The main conclusion of this work is that these projections are largely intrahypothalamic, with smaller components directed toward the brainstem and telencephalon. Although the intrahypothalamic pathways are very complex and intermix at various levels, we conclude that dorsomedial nucleus outputs follow three distinct ascending pathways: periventricular, coursing through the hypothalamic periventricular zone; ventral, traveling beneath the medial zone; and lateral, ascending in medial parts of the lateral hypothalamic area. Within the hypothalamus, the most densely innervated areas are the paraventricular nucleus, other dorsal regions of the periventricular zone, the preoptic suprachiasmatic nucleus, and the parastrial nucleus. Other significant terminal fields include the median preoptic, anteroventral periventricular, lateral part of the medial preoptic, and anteroventral preoptic nuclei; and the retrochiasmatic (including perisuprachiasmatic) area. Descending projections follow two pathways that also converge at various levels: a dorsal pathway in the midbrain periventricular system travels through, and primarily innervates, the periaqueductal and pontine gray, and a ventral pathway extends through ventromedial regions of the brainstem. Although sparse, fibers in the later pathway can be traced as far caudally as the nucleus of the solitary tract. The results are discussed relative to the pathways and properties of nearby hypothalamic medial zone nuclei. Dorsomedial nucleus projections are similar to certain other nuclei (e.g., anteroventral periventricular and parastrial) with predominantly intrahypothalamic projections, and different from those arising in the medial zone nuclei (medial preoptic, anterior hypothalamic, ventromedial, and mammillary.

Afferent Pathways↗

Interconnectivity between the amygdaloid complex and the amygdalostriatal transition area: a PHA-L study in rat.

The amygdala orchestrates the formation of behavioral responses to emotionally arousing stimuli. Many of these responses are initiated by the central nucleus, which converges information from other amygdaloid nuclei. Recently, we observed substantial projections from the amygdala to the amygdalostriatal transition area, which is located dorsal to the central nucleus. These projections led us to question whether the amygdalostriatal transition area has a role in the initiation of behavioral responses in emotionally arousing circumstances. To explore this anatomically, we traced the interconnections between the amygdalostriatal transition area and the amygdaloid complex using the anterograde tracer Phaseolus vulgaris-leucoagglutinin. The lateral (the medial division and the caudal portion of the dorsolateral division) and the accessory basal nuclei (the parvicellular division) provide moderate-to-heavy projections to the amygdalostriatal transition area. Projections back to the amygdala are light and are composed of thin, faintly stained varicose fibers that resemble the labeling of cholinergic terminals. The extra-amygdaloid outputs of the amygdalostriatal transition area are sparse and include moderate projections to the caudoventral globus pallidus, the ansa lenticularis, and the substantia nigra pars lateralis. These data suggest that the amygdalostriatal transition area is one of the major targets for projections originating in the lateral and accessory basal nuclei of the amygdala. Via these pathways, emotionally significant stimuli can evoke behavioral responses that are different from those initiated via projections from the amygdala to the central nucleus. One such candidate response is the orienting response (i.e., saccadic eye movements and head direction) in a pathway that includes a projection from the lateral/accessory basal nucleus of the amygdala to the amygdalostriatal transition area, and from there to the substantia nigra, pars lateralis.

Amygdala↗

Quantitation of immunoglobulin-bearing lymphocytes and the lymphocyte response to PHA in experimental pyelonephritis.

In these experiments the effect of experimental pyelonephritis on the distri-ution of B lymphocytes in the peripheral blood and lymphoid sites in the rat has been determined and the functional capacity of T cells during the course of infection has been investigated. The studies have shown that renal infection affects the distribution of lymphocytes and has a marked effect on the functional capacity of splenic T lymphocytes early in infection. Most of the lymphocytes forming the round cell infiltrate in the kidney have been identified as thymus-derived lymphocytes on their surface labelling characteristics. Evidence is presented to demonstrate the inability of T lymphocytes to function normally in the environment of the kdiney. It is suggested that ablation of cell-mediated immunity may be a factor contributing to the persistence of renal infection.

Animals↗

Cell cycle distribution defect in PHA-stimulated T lymphocytes of sickle cell disease patients.

T lymphocytes from normal human controls and sickle cell disease (SCD) patients were isolated from peripheral blood and cultured for 72 hours following addition of phytohemagglutinin. The ratio for the fraction of cells in DNA synthesis (S phase) over the fraction in G2 phase (S/G2) was significantly higher in SCD patients in comparison to the controls (mean +/- SD) (4.01 +/- 0.78 vs. 2.78 +/- 0.76, P less than 0.02). Following in vivo zinc supplementation to two subjects, the S/G2 ratio was normalized. We conclude that the distribution of T lymphocytes in cell cycle is altered in SCD patients and that this effect may be zinc-dependent.

Adolescent↗

Failure of PHA-stimulated i(12p) lymphocytes to divide in Pallister-Killian syndrome.

The diagnosis of Pallister-Killian syndrome (PKS) is confirmed by tissue-specific mosaicism of i(12p). The isochromosome is found in skin fibroblasts and bone marrow, but rarely in peripheral lymphocytes. The nature of the isochromosome loss was evaluated using 2 techniques: micronucleus formation for anaphase lag and in situ DNA hybridization for mosaicism in interphase cells. Cells from serial cultured fibroblasts, peripheral blood lymphocytes, and bone marrow from 4 PKS patients were used for the above analysis. Micronucleus formation was similar for PKS and normal diploid cultures, ruling out loss of i(12p) by anaphase lag as the major mechanism of in vitro mosaicism. In situ hybridization using an alpha satellite DNA probe for chromosome 12 was used to examine the presence of the i(12p) in interphase fibroblasts from 1 patient and lymphocytes from 2 patients (age 8 weeks and 1 day). The i(12p) was present in a significantly higher proportion of interphase nuclei in peripheral lymphocytes than in metaphase, suggesting the initial loss of the isochromosome is exaggerated in metaphase by selective division in vitro. In situ hybridization of peripheral lymphocyte interphase cells with chromosome 12 specific probes may be a useful supplemental procedure for the diagnosis of PKS, at least in the newborn infant.

Cell Division↗

PPD-, PWM-, and PHA-induced interferon in stable multiple sclerosis: association with HLA-Dw2 antigen and clinical variables.

Interferon production after stimulation of lymphocytes with purified protein derivative, pokeweed mitogen, and phytohemagglutinin was studied in 39 patients with stable multiple sclerosis (MS) and 39 age- and sex-matched controls. Stable MS patients produced less interferon, and the number of subjects producing undetectable amounts of interferon was higher in the MS group (11/39) than in the control group (2/39). A tendency toward an association between low interferon production and HLA-Dw2 antigen was found in MS patients. There was no clear-cut correlation between interferon production and the duration of disease or disability of the patients. Although there was no systematic correlation of age with interferon production, patients older than 55 years tended to be very poor interferon producers.

Female↗

Projections from the amygdalo-piriform transition area to the amygdaloid complex: a PHA-l study in rat.

The amygdalo-piriform transition area is a poorly defined region in the temporal lobe that is heavily connected with the olfactory system. As part of an ongoing project aimed at understanding the neuronal pathways that provide sensory information to the amygdala, we investigated the cytoarchitectonic and chemoarchitectonic features of the amygdalo-piriform transition area and its connections to the amygdaloid complex in 13 rats by using the anterograde tracer, Phaseolus vulgaris-leucoagglutinin. Our analysis indicates that the amygdalo-piriform transition area has medial (rostral and caudal portions) and lateral parts. The rostromedial part projects heavily to the intermediate and lateral divisions of the central nucleus, whereas the caudomedial part projects mainly to the medial division. The lateral part of the amygdalo-piriform transition area projects heavily to the capsular and lateral divisions of the central nucleus. Electron microscopic analysis revealed that the projection to the lateral division of the central nucleus forms asymmetric contacts with the spines and shafts of postsynaptic neurons and, therefore, is assumed to be excitatory. The amygdalo-piriform transition area also projects moderately to other amygdaloid nuclei, including the parvicellular division of the basal nucleus, the anterior cortical nucleus, and the nucleus of the lateral olfactory tract. The lateral and medial parts of the amygdalo-piriform transition area also project to the distal temporal CA1 and distal temporal subiculum, respectively. Unlike the adjacent entorhinal cortex, the amygdalo-piriform transition area does not project to the dentate gyrus. These data suggest that the amygdalo-piriform transition area is a region that influences both emotional and memory processing in parallel by means of pathways to the amygdala and the hippocampus, respectively.

Amygdala↗

Projections from the amygdaloid complex to the piriform cortex: A PHA-L study in the rat.

Projections from the amygdala to the piriform cortex are proposed to provide a pathway via which the emotional system can modulate the processing of olfactory information as well as mediate the spread of seizure activity in epilepsy. To understand the details of the distribution and topography of these projections, we injected the anterograde tracer Phaseolus vulgaris-leucoagglutinin into different nuclear divisions of the amygdaloid complex in 101 rats and analyzed the distribution and density of projections in immunohistochemically processed preparations. The heaviest projections from the amygdala to the piriform cortex originated in the medial division of the lateral nucleus, the periamygdaloid and sulcal subfields of the periamygdaloid cortex, and the posterior cortical nucleus. The heaviest terminal labeling was observed in layers Ib and III of the medial aspect of the posterior piriform cortex. Lighter projections to the posterior piriform cortex originated in the dorsolateral division of the lateral nucleus, the magnocellular and parvicellular divisions of the basal and accessory basal nuclei, and the anterior cortical nucleus. The projections to the anterior piriform cortex were light and originated in the dorsolateral and medial divisions of the lateral nucleus, the magnocellular division of the basal and accessory basal nuclei, the anterior and posterior cortical nuclei, and the periamygdaloid subfield of the periamygdaloid cortex. The results indicate that only selective amygdaloid nuclei or their subdivisions project to the piriform cortex. In addition, substantial projections from several amygdaloid nuclei converge in the medial aspect of the posterior piriform cortex. Via these projections, the amygdaloid complex can modulate the processing of olfactory information in the piriform cortex. In pathologic conditions such as epilepsy, these connections might provide pathways for the spread of seizure activity from the amygdala to extra-amygdaloid regions.

Amygdala↗

Amygdalonigral pathway: an anterograde study in the rat with Phaseolus vulgaris leucoagglutinin (PHA-L).

The projection from the central nucleus of the amygdala to the substantia nigra was labeled by injections of the anterograde tracer Phaseolus vulgaris leucoagglutinin into different subregions of the nucleus. A sparse projection of labeled bouton-like swellings was observed in the rostral, medial substantia nigra pars compacta and ventral tegmental area from all subregions of the central nucleus of the amygdala that were injected. A dense projection of labeled axons and bouton-like swellings was observed in the lateral part of the substantia nigra pars compacta and pars lateralis when the injection site included the dorsal and rostral central nucleus. Heavy labeling was also seen in the lateral retrorubral field in these cases. In no instances were labeled terminals observed in the substantia nigra pars reticulata. The same pattern of labeling in the lateral substantia nigra and retrorubral field was seen after injections rostral to the central nucleus or dorsal and medial to it in the sublenticular region. The results suggest that the amygdalonigral pathway contributes to the innervation of extensive areas of the substantia nigra pars compacta. The major component of the pathway, however, projects only to a subregion of the substantia nigra. The origin of this pathway is confined to a discrete region of the dorsal central nucleus of the amygdala but extends rostrally into an area that is part of the "extended amygdala."

Amygdala↗

Cerebellar nucleo-olivary projections in the rat: an anterograde tracing study with Phaseolus vulgaris-leucoagglutinin (PHA-L).

In order to evaluate the reciprocity of olivo-cerebellar and cerebello-olivary connections, a detailed description of the cerebellar nucleo-olivary projection in the rat is presented using small, iontophoretic injections of the anterograde tracer Phaseolus vulgaris-leucoagglutinin. Sparse projections were found to arise from the rostral part of the medial cerebellar nucleus toward the lateral part of the caudal medial accessory olive. Its medial parts receive a projection from the dorsolateral protuberance of the medial cerebellar nucleus. Caudal and lateral regions of the medial cerebellar nucleus project to the "beta" group and dorsomedial cell column. Heavy olivary projections to circumscribed parts of the inferior olive were found after injections in the remaining cerebellar nuclei. The medial part of the posterior interposed nucleus connects to caudolateral areas of the rostral half of the medial accessory olive, whereas lateral areas project to more rostromedial parts. The most ventromedial part of the lateral cerebellar nucleus projects to the ventrolateral outgrowth. Adjacent medial, ventral, and caudal regions connect to the ventral leaf of the principal olive. The cerebellar origin of the projection to its dorsal leaf is located in lateral, dorsal, and rostral parts of the lateral cerebellar nucleus. The dorsolateral hump projects to the dorsomedial group of the rat inferior olive. Rostromedial projections to the dorsal accessory olive originate from the lateral part of the anterior interposed nucleus, whereas its medial parts project to more lateral and caudal regions of this olivary subnucleus. The dorsal fold of the dorsal accessory olive does not receive a projection from the cerebellar nuclei but from the lateral vestibular nucleus. No cerebellar projections were found to the dorsal cap. Relatively strong ipsilateral projections, which were the mirror images of the contralateral projections, were observed in the dorsomedial group, rostral medial accessory olive, and ventral leaf of the principal olive. When both the inferior olive and the cerebellar nuclei are considered as folded but continuous sheets of grey matter, the complete nucleo-olivary projection can be described as a simple transformation.

Animals↗

Projections from the posteroventral cochlear nucleus to the superior olivary complex in guinea pig: light and EM observations with the PHA-L method.

The efferent neural projections from posteroventral cochlear nucleus to the superior olivary complex in guinea pig were examined with the Phaseolus vulgaris-leucoagglutinin anterograde tract-tracing method. Light microscopic analysis demonstrated that the posteroventral cochlear nucleus of guinea pig bilaterally projects to the superior para-olivary nucleus and the rostral, medioventral, and lateroventral peri-olivary regions. Ipsilaterally, the posteroventral cochlear nucleus projects to the lateral superior olive, the caudal peri-olivary region, and areas immediately surrounding the capsule of the lateral superior olive. Contralaterally, the posteroventral cochlear nucleus projects to the medial nucleus of the trapezoid body. All of these projection axons travel in the trapezoid body and their terminals make, primarily, en passant endings upon their targets. Exclusively within the contralateral medial nucleus of the trapezoid body, some neurons terminate also in calyceal endings. The assumption that immunolabeled structures observed with light microscopy made actual synaptic contact in their respective target areas was confirmed with electron microscopy. With postembedding immunocytochemical procedures applied to thin sections, the electron microscope revealed labeled synaptic vesicles and pre- and postsynaptic membrane specializations. The projection pattern from posteroventral cochlear nucleus was found to be topographically organized in three distinct regions. The more dorsally located neurons of the posteroventral cochlear nucleus terminated dorsomedially in the ipsilateral lateral superior olive, ventromedially in the contralateral superior para-olivary nucleus, and medially in the contralateral medioventral peri-olivary region. The more ventrally located neurons of the posteroventral cochlear nucleus terminated dorsolaterally in the ipsilateral lateral superior olive, dorsolaterally in the contralateral superior para-olivary nucleus, and laterally in the contralateral medioventral peri-olivary region.

Animals↗

Analysis of the PHA granule-associated proteins GA20 and GA11 in Methylobacterium extorquens and Methylobacterium rhodesianum.

Electrophoretic analysis of the proteins bound to poly(3-hydroxybutyric acid), PHB-, granules in Methylobacterium extorquens, M. rhodesianum as well as the PHB-leaky mutants Mu 1 and Mu 11, which were isolated from the latter, resulted in two dominant low-molecular weight proteins, which were referred to as GA11 and GA20. After purification of these proteins antibodies against the GA11 and GA20 protein of M. extorquens were obtained. Both proteins bound to the surface of PHB granules as revealed by immunoelectron microscopy of whole cells of M. extorquens and M. rhodesianum. With cells of the PHB-leaky mutants Mu 1 and Mu 11 no specific labeling was observed. The N-terminal amino acid sequences of the GA11 and the GA20 protein were determined. We found significant homologies between the sequences of the investigated strains. The use of oligonucleotide probes based on the N-terminal sequences of the GA20 protein from M. rhodesianum to identify the corresponding structural genes in various genomic libraries failed.

Acetyl-CoA C-Acyltransferase↗