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At least 19 recordsLinked to original sources

PubMed1991

Early undifferentiated connective tissue disease. I. Early clinical manifestation in a large cohort of patients with undifferentiated connective tissue diseases compared with cohorts of well established connective tissue disease.

We identified a cohort of 410 patients with connective tissue disorders (CTD) of less than or equal to 1 year duration among the participating clinics of the Cooperative Systematic Studies of the Rheumatic Diseases Program. Fifty-seven had rheumatic arthritis (RA), 57 systemic lupus erythematosus, 37 poly/dermatomyositis, 46 scleroderma, and 213 early undifferentiated CTD, including patients with Raynaud's phenomenon, unexplained polyarthritis or at least 3 CTD manifestations such as rashes, myalgias, etc. Baseline clinical data are now being reported. The followup of these patients may prove to be valuable in understanding these diseases. To our knowledge no similar cohort of patients is available for further investigation.

Adolescent↗

PubMed1978

Anatomical mapping of retino-tectal connections in developing and metamorphosed Xenopus: evidence for changing connections.

Neural connections between the eye and optic tectum in Xenopus laevis were anatomically traced by observing the tectal location of Wallerian degeneration after discrete retinal lesion. These retinotectal connections were mapped in postmetamorphic frogs and tadpoles at stage 51, the stage at which retinal axons have grown into about the rostral one-half of the tectum. The course of the experimental degeneration was the same in frogs and tadpoles, but degeneration proceeded faster in the younger animals. In the frogs, connections were ordered, with nasal retina mapping to the caudal part of the tectum and temporal retina mapping to the rostral tectum. In the tadpoles, within the innervated area at the rostral tectum, the retino-tectal connections were generally organized as in the adults, with the temporal retina mapping to the rostral part of the innervated tectum and nasal retina mapping primarily to the caudal part. But a portion of the nasal fibers consistently mapped to the far rostral tectum as well. Electron microscopic observations showed degenerating synaptic terminals at both rostral and caudal portions of the innervated tectum after lesion of just the nasal retina. Degeneration was not seen in control animals. These results indicate that some fibers (particularly from nasal retina) may shift their terminals caudally on the tectum to match tectal growth and produce the adult pattern of connections. If there is such connection readjustment, the 'aberrant' connections from nasal retina in tadpoles may be an indication of this process.

Animals↗

PubMed1992

Influence of synaptic identity on single-Ia-afferent connectivity and EPSP amplitude in the adult cat: homonymous versus heteronymous connections.

1. This study makes use of the pattern of synaptic connections between motoneurons and Ia afferents of triceps surae muscles in the cat to test the relative importance of synaptic identity, neuronal size, and neuronal topography as determinants of Ia-afferent connectivity and excitatory postsynaptic potential (EPSP) amplitude. 2. The synaptic actions of single-Ia medial gastrocnemius (MG) afferents were measured by intracellular recording in MG and lateral gastrocnemius (LG) motoneurons. The spike-triggered averaging technique was used to measure EPSPs generated by homonymous or heteronymous Ia afferents and motoneurons, i.e., neurons supplying the same or different muscles, respectively. In agreement with earlier studies, the pooled sample showed that the number of functional connections and the size of EPSPs were both significantly greater for homonymous than for heteronymous neurons. 3. Afferent conduction velocity, motoneuron conduction velocity, rheobase current, and position of the motoneuron relative to the spinal cord afferent entry were all correlated with EPSP amplitude, but the amplitude difference between homonymous and heteronymous connections remained significant after the statistical removal analysis of covariance (ANCOVA) of the contribution of these variables. Stepwise multiple-regression analysis showed that synaptic identity explained the greatest fraction of the variance in EPSP amplitude (9%), with significant but smaller fractions accounted for by rheobase current or motoneuron conduction velocity. 4. In a separate experiment, the monosynaptic affects from both homonymous and heteronymous single-Ia afferents were examined in each of 88 MG or LG motoneurons. The single-Ia afferents used in this portion of the study were sampled from both MG and LG muscles and selected for similar conduction velocities and spinal cord entry points.(ABSTRACT TRUNCATED AT 250 WORDS)

Afferent Pathways↗

PubMed1978

Pattern separability and the effect of the number of connections in a random neural net with inhibitory connections.

It has been claimed that pattern separation in cerebellar cortex plays an important role in controlling movements and balance for vertebrates. A number of the neural models for cerebellar cortex have been proposed and their pattern separability has been analyzed. These results, however, only explain a part of pattern separability in random neural nets. The present paper is intended to study an extended theory of pattern separability in a new model with inhibitory connections. In addition to this, the effect of the number of connections on pattern separability is cleared up. It is also shown that the signal from the inhibitory connections has crucial importance for pattern separability.

Action Potentials↗

PubMed1991

Discordant atrioventricular connection and concordant ventriculoarterial connection in situs inversus: isolated ventricular noninversion.

A case of discordant atrioventricular (AV) connection and concordant ventriculoarterial (VA) connection (with aortomitral fibrous continuity and tricuspid pulmonary discontinuity) in situs inversus (I, D, I) is reported because of its rarity. This segmental combination with abnormally related great arteries in the absence of anomalies of venous connections and/or splenic anomalies is extremely rare.

Female↗

PubMed1978

[Nuclei of the mammillary bodies and their fiber connections in cattle (Bos taurus var. domesticus). 2. Fiber connections of the mammillary bodies in cattle].

1. In the present information the course of fibre pathways which are connected with the mammillary body of the cattle is described in 14 series of brains (6 frontal, 4 sagittal, 4 horizontal series, stained by the combined cell-fibre-method after KLUVER and BARRERA and by the method for myelined fibres after HEIDENHAIN). 2. The mammillary body of cattle is connected with four main fibre systems. These are the fornix and the mamillary peduncle as well as the mamillo-thalamic and the mamillo-tegmental tracts. 3. The fornix system first of all represents a rich myelined fibre connection between the hippocampus and the mamillary body. But also fornix fibres entering the poor-myelined regions of the hypothalamus and the mesencephalon have been demonstrated. 4. The mamillary peduncle ascending from the mesencephalon can be traced to the lateral mamillary nucleus. 5. The mamillo-thalamic tract of cattle has its origin in the mamillary body with the mamillotegmental tract associated to a common principal mamillary tract and passes to the complex of the anterior nucleus of the thalamus, while the mamillo-tegmental tract branching off from it curves into the mesencephalon.

Animals↗

PubMed1978

Connective tissue activation. XIII. Stimulation of sulfated glycosaminoglycan synthesis in human connective tissue cells by peptide mediators from lymphocytes and platelets.

CTAP-I from lymphocytes and CTAP-III from platelets markedly stimulated 35SO4= incorporation into chondroitin 4/6 sulfate and dermatan sulfate synthesized by human synovial, dermal, and cartilage connective tissue cells in vitro. These agonists promoted synthesis of the GAG carbon chain as well as sulfate incorporation. Both RNA and protein synthesis were required for these mediators to be effective in stimulating synthesis of connective tissue matrix components. A major part of the capacity of normal serum to stimulate sulfate incorporation into GAG's may reside in CTAP-III.

Blood Platelets↗

PubMed1992

[Connective tissue polypeptides in serum: new parameters of connective tissue synthesis and degradation in liver fibrosis].

With the invention of drugs that effectively and specifically inhibit excessive collagen synthesis in the liver, a growing interest in serum assays that assess fibrogenesis, i.e. the de novo formation and fibrolysis, i.e. the removal of connective tissue in the liver, may be anticipated. Several serum assays for connective tissue polypeptides fulfil the criteria of sensitivity and specificity for chronic liver diseases. The aminoterminal procollagen type III peptide (PIIINP) correlates with hepatic fibrogenesis, whereas the propeptides of basement membrane collagen (PIVNP and PIVCP) and the basement membrane glycoprotein laminin reflect the enhanced turnover of basement membranes of the sinusoids as well as of proliferating bile ducts and blood vessels in active fibrosis. Circulating collagen type VI results from degradation of interstitial microfilaments and undulin appears to be released upon remodeling of the hepatic architecture. Combined measurement of selected parameters may allow a non-invasive assessment of the balance between fibrogenesis and fibrolysis on a day-to-day basis, especially in the light of potential antifibrotic therapy.

Biopsy↗

PubMed1978

Free serum ribonucleoprotein in mixed connective tissue disease and other connective tissue diseases.

Free ribonucleoprotein (RNP) was found by means of a hemagglutination inhibition assay in 21 sera from 11 of 25 patients with mixed connective tissue disease (MCTD) who had 299 sera studied. Free RNP tended to appear when anti-RNP antibody titers fell or when prednisone was initiated or increased. Five of 72 SLE patients (211 sera) had free RNP in at least one serum. Three of them had anti-RNP antibodies in other sera. Free serum RNP was found in one of 20 patients with scleroderma and in two of seven patients with connective tissue disease "overlap" syndromes without anti-RNP.

Antibodies, Antinuclear↗

PubMed1991

Ventricular function during supine bicycle exercise in univentricular connection with absent right atrioventricular connection.

Fourteen patients with univentricular connection, absent right connection (tricuspid valve atresia) and normally related great arteries underwent rest and supine bicycle exercise equilibrium radionuclide blood pool studies. Ejection fraction, heart rate, systemic blood pressure and oxygen saturation (ear oximetry) were measured. There were 6 male and 8 female patients. Mean age +/- standard error of the mean was 14.5 +/- 1.1 years (range 6.3 to 21.1). Eight patients (group 1) had systemic to pulmonary shunts placed as palliation 8.2 +/- 2.2 years before study and 6 patients (group II) had caval to pulmonary shunts placed 11.8 +/- 1.6 years previously. Ejection fraction at rest was 54 +/- 2% and an abnormal response to exercise (failure of ejection fraction to increase greater than or equal to 5% from rest to peak exercise) was found in 9 of 14 patients. When analyzed separately, ejection fraction at rest in group I was higher than in group II; however, this difference disappeared at peak exercise. There was a significant negative correlation between ejection fraction at peak exercise and the interval since palliative surgery, although it was not apparent at rest. These data suggest that ventricular function is compromised during exercise and that abnormal performance is influenced by long-standing volume overload. Importantly, this abnormal state is concealed at rest and the choice of palliative shunting procedure appears to have little effect on normalizing pump performance.

Adolescent↗

PubMed1975

Some connections of the entorhinal (area 28) and perirhinal (area 35) cortices of the rhesus monkey. III. Efferent connections.

In this investigation the efferent projections of the entorhinal and prorhinal cortices relative to their sites of termination in the hippocampus and fascia dentata were investigated in the rhesus monkey using experimental silver impregnation methods. Contrary to the often cited observations of Lorente de No, all entorhinal areas, including the laterally lying prorhinal cortex, were found to give rise to the perforant pathway, and furthermore, each cytoarchitectonically defined subarea was found to contribute a unique component. These perforant pathway components terminate in distinct regions of the dendritic zones of the fascia dentata granule cell and the hippocampal pyramidal cell. A previously undescribed projection to the prosubiculum and hippocampus has been found to originate from the prorhinal cortex which forms the medial wall of the rhinal sulcus along the lateral-most portion of the entorhinal cortex in the rhesus monkey. These results, in conjunction with our previous observations regarding differential afferents to the entorhinal cortex, indicate that specific afferent and efferent connections characterize each cytoarchitectonically definable subareas of this periallocortical region. Additionally, they indicate that the perforant pathway might be conceptualized as the final link in a multisynaptic series of connections instrumental in providing the hippocampus with potential modality specific and multimodal input.

Animals↗

PubMed1991

Arrhythmias after the Fontan procedure. Comparison of total cavopulmonary connection and atriopulmonary connection.

Arrhythmia was compared between 40 consecutive patients (pts) undergoing atriopulmonary connection (APC) and 40 undergoing total cavopulmonary connection (TCPC), between 1986 and 1990. Patients were not randomized, and those undergoing APC predominantly had tricuspid atresia (57.5% versus 15%) compared with pts undergoing TCPC who had more varied and complex cardiac defects. Before surgery there was no significant arrhythmia in either group. Hospital mortality was 15/40 and 6/40 for APC and TCPC, respectively (p less than 0.05). Early after APC nine pts developed atrial flutter (AFL) and eight died, while after TCPC only two developed AFL, and neither died (p less than 0.01). Fatal junctional ectopic tachycardia occurred in one pt in each group. During follow-up (38 +/- 8.5 months after APC versus 20 +/- 10 months after TCPC), new arrhythmia was uncommon (two AFL after APC with one death versus two AFL and one supraventricular tachycardia after TCPC with no deaths). Ambulatory ECG during follow-up showed arrhythmia in two APC and six TCPC pts (p = NS). The incidence of early arrhythmia and mortality associated with early arrhythmia appears to be less after TCPC compared with APC.

Arrhythmias, Cardiac↗

PubMed1991

[Herpes zoster in connective tissue diseases: II. Rheumatoid arthritis and mixed connective tissue disease in comparison with systemic lupus erythematosus].

We investigated the incidence of herpes zoster (HZ) and the immunological state to HZ in patients with rheumatoid arthritis (RA) and mixed connective tissue disease (MCTD) in comparison with systemic lupus erythematosus (SLE). HZ occurred in 6 (25%) out of 24 patients with RA and 4 (22%) out of 18 patients with MCTD. One patient had had HZ before the diagnosis of RA. On the other hand, all 4 patients with MCTD had had HZ before the diagnosis of MCTD. The patients with RA and MCTD showed normal or higher antibody titers to varicella zoster virus (VZV) than normal subjects as assayed by both complement fixation technique and neutralization test. However, the antibody levels were not very high compared to those in patients with SLE. On the other hand, only 7 (50%) of 14 patients with RA and 4 (40%) of 10 patients with MCTD showed positive skin reactions to VZV antigen, whereas all 15 normal subjects had positive reactions. Thus, cellular immunity to VZV was thought to be impaired in these diseases. In the patients who were receiving less than 10 mg/day of prednisolone, 7 (64%) of 11 had positive skin reactions in RA patients and 3 (60%) out of 5 patients with MCTD, whereas none (0%) out of 3 patients with RA and 1 (20%) out of 5 patients with MCTD who were receiving 10 mg/day or more prednisolone showed positive skin reactions. These results suggest that the high incidence of HZ in patients with RA and MCTD is probably due to an impaired cellular immunity as in the case of SLE.

Adult↗

PubMed1992

Connective tissue activation. XXXV. Detection of connective tissue activating peptide-III isoforms in synovium from osteoarthritis and rheumatoid arthritis patients: patterns of interaction with other synovial cytokines in cell culture.

OBJECTIVE: To determine whether extracts of unincubated osteoarthritis (OA) and rheumatoid arthritis (RA) synovial tissue contain connective tissue activating peptide-III (CTAP-III) isoforms and prostaglandin E2 (PGE2), and whether such extracts have growth-promoting activity, and to determine whether binary combinations of CTAP-III with other cytokines reported to be present in synovial tissue lead to synergistic, additive, or inhibitory effects on growth. METHODS: Acid-ethanol extracts of human synovium were examined for growth-promoting activity by measuring formation of 14C-glycosaminoglycan (14C-GAG) and 3H-DNA in synovial cell cultures; PGE2 was measured by enzyme immunoassay, and CTAP-III isoforms were identified by Western blotting of extracted proteins separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Growth-promoting activity of CTAP-III and other cytokines was tested in synovial cultures treated with the agonists singly and in binary combination, by measuring changes in synthesis of 14C-GAG and 3H-DNA. RESULTS: Platelet-derived CTAP-III and a cleavage isoform with the electrophoretic mobility of CTAP-III-des 1-15/neutrophil-activating peptide-2 (NAP-2) and PGE2 were found in biologically active extracts of synovial samples from patients with RA and OA. Five growth factors (recombinant epidermal growth factor [rEGF], recombinant interleukin-1 beta [rIL-1 beta], basic fibroblast growth factor [bFGF], PGE1, and PGE2) in binary combination with CTAP-III showed synergism in stimulating GAG synthesis; two (recombinant platelet-derived growth factor type BB [rPDGE-BB] and recombinant transforming growth factor beta [rTGF beta]) had an additive effect. In combination with CTAP-III, rEGF and rPDGF-BB had a synergistic effect in promoting DNA synthesis, rTGF beta and rbFGF had an additive effect, and rIL-1 beta, PGE1, and PGE2 were antagonistic. CONCLUSIONS: The results suggest that, in addition to endogenous factors, CTAP-III and other platelet-derived cytokines may play roles in regulating synovial cell metabolism in RA and OA, and that combinations of growth factors may be more significant than single agents in amplification or suppression of important cell functions.

Arthritis, Rheumatoid↗

PubMed1976

Molecular connectivity V: connectivity series concept applied to density.

The concept of the expanded series of the connectivity index, chi, is introduced and applied to a consideration of the density of three classes of molecules. Correlations are found using two terms in the expanded series. A preliminary reflection on the extended series terms is made. It is noted that the regression equation constant in the three studies is close to the phase volume, 0.7402, and the possible significance of this fact is discussed.

Alcohols↗

PubMed1991

The efferent connections of the lateral septal nucleus in the guinea pig: intrinsic connectivity of the septum and projections to other telencephalic areas.

The distribution of efferent fibers originating in the lateral septal nucleus was investigated in guinea pigs by means of anterograde tracing with Phaseolus vulgaris-leucoagglutinin (PHA-L). Special emphasis was placed on the intraseptal fiber systems. The fibers originating from the different subnuclei of the lateral septal nucleus formed massive horizontal connections in the rostrocaudal axis. Projections to the contralateral, congruent subnuclei were also detected. In the medial septum/diagonal band of Broca complex the largest number of PHA-L-stained fibers was found after application of the tracer into the dorsal subnucleus of the lateral septal nucleus; the density of the efferent fibers decreased progressively after injection into the intermediate or ventral subnuclei. In all cases the diagonal band contained a much higher number of efferent fibers from the lateral septal nucleus than from the medial septal nucleus. In the medial septal nucleus, terminal labeling was generally sparse. Other telencephalic areas (organum vasculosum of the lamina terminalis, nucleus accumbens, bed nucleus of the stria terminalis, amygdala, hippocampal complex, and other cortical areas) contained varying numbers of labeled projections. In double-labeling experiments, a close spatial relationship between PHA-L-stained fibers and vasoactive intestinal polypeptide-immunoreactive perikarya was observed in several of these target areas.

Animals↗

PubMed1977

Retrograde axonal transport of 125I-tetanus toxin as a tool for tracing fiber connections in the central nervous system; connections of the rostral part of the rat neostriatum.

After previous studies had shown that 125I-tetanus toxin is taken up with high efficiency by all (adrenergic, sensory and motor)peripheral nerve terminals and that it is transported retrogradely by intraaxonal transport to the corresponding cell bodies, the present experiments were designed to investigate whether 125I-tetanus toxin could be used as a tool for retrograde tracing of fiber connections in the central nervous system and how the results obtained compared with other available retrograde tracing methods. Three to 12 h after injection of 125I-tetanus toxin into the rostral part of the nucleus caudatus of the rat, heavily labeled nerve cells were found in the substantia nigra zona compacta, in Forel field H2 and parts of the zona incerta, and in specific thalamic intralaminar nuclei (nucleus medialis pars lateralis and nucleus parafascicularis). Moderately labeled neurons were observed in the nucleus ventralis thalami and its dorsomedial part, in the nucleus raphe dorsalis and in the frontal, cingular and occipital cortex. Besides the labeling by retrograde transport, orthograde transport of radioactivity occurred in a striatonigral system. The high sensitivity and reliability of this method, even after injection of very small amounts of protein in a very small volume, represent important advantages over most of the commonly used tracing methods.

Animals↗

PubMed1976

Molecular connectivity. 6. Examination of the parabolic relationship between molecular connectivity and biological activity.

The topologically derived, nonempirical molecular connectivity index, chi, for several classes of compounds is shown to be parabolically related to the biological activities of these compounds. Similar nonlinear relationships were previously shown between the octanol-water partition coefficients, expressed as log P, of the compounds and their biological activities. These and previous studies indicate that many physiochemical properties presently used in structure-activity studies may be intermediaries between the nonempirical molecular structure encoded in chi and measured biological activities.

Amines↗