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Biomedical subjects

H Brand

Publications and source records attributed to H Brand.

At least 55 records · Page 3Linked to original sources

Interleukin 1 beta mediates stress-induced immunosuppression via corticotropin-releasing factor.

Intracerebroventricular (icv) infusion of human interleukin 1 beta (IL-1) into intact and adrenalectomized rats impairs immune function. Using antibody to IL-1 as well as an inhibitor of IL-1 action, we sought to determine if endogenous IL-1 in the central nervous system has a physiological role in mediating the immunosuppressive effects of stress. Compared with freely moving controls, rats given intermittent electric shock to the tail for 40 min exhibited a fall in T lymphocyte proliferation and natural killer (NK) cell cytotoxicity of 33% and 38%, respectively; however, when pretreated with icv human IL-1 monoclonal antibody, which significantly crossreacts with rat IL-1, the decrement was attenuated to 14.6% and 15%, respectively. When rats were pretreated with icv alpha-MSH, which blocks many IL-1 effects, shock-induced suppression of 42% in both T lymphocyte proliferation and NK cytotoxicity were blunted to 33% and 31%, respectively. Similar results were found in adrenalectomized rats. These findings suggest that endogenous IL-1 is a physiologically relevant mediator of the immune response to stress. As IL-1 has been reported to release CRF, which we have shown always plays a significant role in stress-induced immunomodulation, we then assessed the relationship of IL-1 and CRF in immunosuppression. Infusion of icv IL-1 caused a decrease of 35% in T lymphocyte proliferation and 34% in NK activity, but pretreatment with CRF antibody icv attenuated IL-1 suppression of T lymphocyte proliferation and NK activity to 10% and 8%, respectively. Comparable results were observed in adrenalectomized rats. These findings suggest that CRF antibody is able to block the immunosuppressive effects of IL-1. To further examine the interaction of CRF in mediating stress-induced immunosuppression, we found that animals pretreated with icv CRF antibody, shocked and then given icv IL-1, had a decrement in T lymphocyte proliferation and NK cytotoxicity of 24% and 21%, respectively, demonstrating that the immunosuppressive effect of icv IL-1 is blocked when central CRF has been neutralized by prior administration of icv CRF antibody. In contrast, animals pretreated with icv IL-1 antibody, shocked and then given icv CRF, had decrements of 38% and 40%, respectively, showing that icv CRF does act even when central IL-1 has been neutralized by prior administration of icv IL-1 antibody. Thus, we conclude there is a sequential relationship between two of the known mediators of stress-induced immunosuppression, with release of central IL-1 followed by that of CRF.

Animals↗

Corticotropin-releasing factor modulates the immune response to stress in the rat.

We examined the role of CRF, a key mediator of the endocrine response to stress, in modulating immunosuppression during the subacute stress of intermittent electrical shock over 1 h. Administration of shock to intact rats resulted in a 74% decrement in T-lymphocyte proliferation and a 59% decrease in natural killer cytotoxicity. Similar suppression of these two parameters of immune function in response to shock was noted in adrenalectomized rats as well. The immunosuppressive effects of this shock were significantly and comparably blunted when both intact and adrenalectomized animals were pretreated 1) iv with either a highly potent polyclonal CRF antibody or a specific CRF antagonist or 2) intracerebroventricularly with either a high affinity monoclonal antibody to CRF or a specific CRF antagonist. An immunomodulatory role for CRF is further supported by the findings that administration of exogenous CRF, either iv (10 micrograms/animal) or intracerebroventricularly (1 microgram/animal), resulted in significant decrements in lymphocyte proliferation and natural killer cytotoxicity, similar to those seen with the stress paradigm. Our observations indicate that CRF plays a significant role in modulating the immune response to subacute stress, largely by adrenal-independent mechanisms.

Adrenalectomy↗

[A test for the detection of speech and language disorders in the acute phase after stroke. Development and clinical application].

No standardized assessment of aphasic symptoms for stroke patients in the acute phase has as yet been published in the German language. Current test batteries such as the AAT are too time-consuming and cannot be performed on severely impaired patients. A short test for the examination of aphasic and dysarthric symptoms has been developed which contains 7 subtests in three main areas: spontaneous speech, comprehension and planning of movements, speech and language abilities. Since abilities in acute cases may only be functionally impaired and often only detectable after stimulation, standardized stimulation is applied in most of the subtests. In this way it is possible to test acute stroke patients for aphasic and dysarthric symptoms. The course of recovery in a typical case is described.

Aged↗

[The value of the transbrachial approach for arterial visualization using a 4-F catheter].

To assess the safety of nonselective intraarterial digital subtraction angiography (DSA) performed from a transbrachial approach with 4-French-catheters, the complications occurring in 158 examinations were studied. Two patients developed local thrombosis and in four patients there were temporary pulse deficits. Three brachial artery catheterisations were unsuccessful due to transient arterial spasm. Our data support the conclusion that nonselective transbrachial DSA is a safe and accurate method, easily employed in an outpatient population.

Adult↗

Discrepancies between gastric mucosal and urinary pepsinogen A patterns and in vitro synthesis and secretion of human pepsinogen.

The relationship between electrophoretic pepsinogen A (PGA) patterns from urine and gastric mucosa was studied in healthy volunteers and in patients with various gastric disorders. Discrepancies between urinary and gastric PGA patterns were found in 63.3% of the individuals. In 9% of the subjects with these discrepancies, the phenotype class in urine was different from that in gastric mucosa. The differences were found in all diagnostic groups. The highest frequency of differences was found in patients with gastric ulcer. The differences were not related to the serum PGA level. More than 80% of the differences were caused by a lower relative intensity of pepsinogen A fraction 5 (Pg5) in urine than in gastric mucosa. The possible origin of differences in PGA isozymogen patterns was studied by organ culture of gastric biopsies. In vitro synthesis and secretion of pepsinogens were studied by electrophoresis and autoradiography. The synthesis rate of PGA in biopsies of 1-2 mm diameter was 40-100 ng/hr. Posttranslational modification of PGA isozymogens was demonstrated. Pg2 and part of Pg4 probably are secondary products of Pg3 and Pg5, respectively. In some individuals the secretion rate of Pg3 was low compared to the other isozymogens. The conversion of Pg3 into Pg2 and the differential secretion of the isozymogens may explain some of the discrepancies between gastric and urinary PGA patterns.

Autoradiography↗

[Neural therapy in tinnitus].

After the examination by ENT-specialists in 96 cases of tinnitus a conventional medical therapy with vasodilators and vitamin A has been tried. This therapy showed unsatisfactory results. Then neural therapy as defined by segmental therapy with a preparation containing lidocaine (Xyloneural) has been applied. The results have been so encouraging, that this method can be advised as basical therapy in tinnitus.

Acupuncture Therapy↗

Levels of circulating and urinary oestrogens during pregnancy in the marmoset monkey (Callithrix jacchus).

The levels of immunoreactive oestrone, oestradiol-17 beta and oestriol in plasma and urine were measured during early, mid- and late pregnancy in the marmoset monkey. In plasma, unconjugated oestrone remained less than 2% of total (conjugated plus unconjugated) oestrone throughout gestation, whereas unconjugated oestradiol-17 beta increased from 3% of the total value in early and mid-pregnancy to 35% in late pregnancy. The reversal in the unconjugated oestrone: oestradiol-17 beta concentration ratio from early (12:1) to late (0 . 15:1) pregnancy occurred despite the continuing predominance of oestrone in terms of total hormone. Total oestriol was measurable but in relatively low concentrations. Oestradiol conjugate was the predominant urinary oestrogen metabolite measured at each stage of pregnancy. The pattern of urinary oestrone and oestradiol-17 beta reflected plasma levels of total hormone, rather than unconjugated hormone, showing no further increase after mid-pregnancy. In contrast, oestriol increased throughout pregnancy and to a proportionately greater extent than oestrone or oestradiol-17 beta, but at lower absolute levels. High-pressure liquid chromatography of urine extract indicated the presence of considerable amounts of oestrogen immunoreactivity not accounted for by oestrone, oestradiol-17 beta and oestriol and with a retention time similar to that of 16 alpha-hydroxyoestrone. Gas chromatography and mass spectroscopy provided further evidence to suggest that 16 alpha-hydroxyoestrone is an abundant urinary oestrogen metabolite during pregnancy in the marmoset monkey.

Animals↗

[Clinical importance of vesico-renal reflux after transurethral resection of bladder tumors].

After any resection of tumors near the ostium you have to expect the vesicoureteral reflux as a complication. If the upper urinary tract is primarily normal, this reflux is of no clinical importance (if of course it is diagnosed and controlled). The resection of the ostium, to be radical, can be done without any doubt. The upper urinary tract is rarely hurted. Concerning out patients it is impossible to see how often the tumor spread in the upper urinary tract by the reflux. However, one must consider it, as one of our cases shows.

Follow-Up Studies↗

Prostaglandin E2 potentiation of platelet aggregation induced by LASS endoperoxide: absent in storage pool disease, normal after aspirin ingestion.

Patients with storage pool disease and normal subjects who ingest aspirin show diminished collagen-induced platelet aggregation and an absent second wave of aggregation with ADP or adrenaline. These 'second-phase' aggregation responses are thought to be mediated by cyclic endoperoxide ('labile aggregation stimulating substance', LASS) that is derived from arachidonic acid and is the precursor of prostaglandin E2 (PGE2) and PGE2alpha. Furthermore, although PGE2 does not directly aggregate platelets, it markedly potentiates LASS-induced aggregation. The platelets of six patients with storage pool disease were capable of converting arachidonic acid to LASS, but the potentiation of LASS-induced aggregation by PGE2 was markedly diminished. In contrast, PGE2-potentiation of LASS aggregation was not reduced after aspirin ingestion. The effects of aspirin can be attributed entirely to its ability to block the enzymatic conversion of arachidonic acid to LASS and PGE2. These findings explain why a mutual correction of the aggregation defects is often seen when aspirin-treated platelets are mixed with storage pool-deficient platelets. This is because 'aspirin platelets' aggregate to the mixture of LASS and PGE2 produced by the storage pool-deficient platelets, which are themselves unresponsive. The findings in storage pool disease support previous conclusions that prostaglandin sensitization of platelets to the pro-aggregatory effects of LASS is an important factor in irreversible aggregation, and could be clinically important.

Adenosine Diphosphate↗

Studies of platelet 5-hydroxytryptamine (serotonin) in storage pool disease and albinism.

Platelets in patients with storage pool disease are markedly deficient in a nonmetabolic (storage) pool of ADP that is important in platelet aggregation. They are also deficient in ATP, although to a lesser degree. In seven patients with this disorder, including one with albinism, platelet 5-hydroxytryptamine (5-HT) levels were reduced in proportion to the reduction in ATP (r = 0.94). Their platelets show diminished capacity to absorb [(14)C]5-HT, and the type of defect was similar to that produced in normal platelets by reserpine, a drug known to inhibit the uptake of 5-HT by the platelet dense granules. Storage pool-deficient platelets also converted more [(3)H]5-HT to [(3)H]5-hydroxyindoleacetic acid than did normal platelets, and the platelets in one of two patients studied contained increased amounts of 5-HT metabolites. The above findings, together with those reported previously, support the conclusion that the capacity of the dense granules (which may be either diminished or functionally abnormal) for storing 5-HT is decreased in storage pool disease; as a result, the 5-HT that enters the platelet may be more exposed to monoamine oxidases present on mitochondrial membranes. This diminished storage capacity (for 5-HT) may also explain why preincubating platelet-rich plasma with 5-HT for 45 min without stirring inhibits subsequent platelet aggregation by 5-HT to a greater degree in patients with storage pool disease than in normal subjects. The latter finding is also consistent with the theory that the aggregation of platelets by 5-HT is mediated by the same receptors on the plasma membrane that are involved in its uptake. The diminished release of platelet-bound [(14)C]5-HT by collagen that we found in these patients, as well as findings in previous studies, suggests that the release reaction may also be abnormal in storage pool disease.

Adenosine Diphosphate↗

Defective ristocetin-induced platelet aggregation in von Willebrand's disease and its correction by factor VIII.

The antibiotic ristocetin, in concentrations of 1.0-1.5 mg/ml, aggregated normal platelets in citrated platelet-rich plasma by a mechanism in which the release reaction played only a minor role. Platelet aggregation by ristocetin in a concentration of 1.2 mg/ml was absent or markedly decreased in 10 patients with von Willebrand's disease. Lesser degrees of abnormality were obtained with a concentration of 1.5 mg/ml. The magnitude of the defect in ristocetin-induced platelet aggregation correlated well with the degree of abnormality of the bleeding time and the levels of antihemophilic factor (AHF, VIII(AHF)) procoagulant activity. In all patients, the defect in ristocetin-induced platelet aggregation was corrected in vitro by normal plasma. Correction was also obtained with a fraction of normal cryoprecipitate that eluted in the void volume with VIII(AHF) after chromatography on a gel that excludes molecules larger than 5 x 10(6). A similar fraction, devoid of VIII(AHF) activity, obtained from patients with von Willebrand's disease had no corrective effect, but fractions obtained from patients with hemophilia were just as effective as those obtained from normal subjects. The correction activity of plasma and partially purified factor VIII was inhibited by a rabbit antibody to human factor VIII but not by a human antibody against VIII(AHF) procoagulant activity. The studies provide further evidence that patients with von Willebrand's disease are deficient in a plasma factor that is necessary for normal platelet function. The activity of this factor appears to be associated with factor VIII but is unrelated to VIII(AHF) procoagulant activity.

Adenosine↗