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Biomedical subjects

L Brandt

Publications and source records attributed to L Brandt.

At least 217 records · Page 12Linked to original sources
PubMed1985

State-dependent learning in hyperactive children receiving methylphenidate.

State-dependent learning refers to a failure of learning mastered under one drug condition to be remembered when tested under another drug condition. Previous studies of state-dependent learning in hyperactive children receiving stimulants have yielded conflicting results. The authors systematically evaluated learning and transfer of learning in children who were or were not receiving methylphenidate and included several design features intended to optimize the likelihood of demonstrating state-dependent learning. They found no evidence of state-dependent learning. These results diminish concern regarding state-dependent effects in hyperactive children who are positive drug responders and who are clinically administered methylphenidate to control their hyperactivity.

Attention Deficit Disorder with Hyperactivity↗
PubMed1985

Early operation and overall outcome in aneurysmal subarachnoid hemorrhage.

Over a 3-year period, 251 individuals in a population of 1.46 million were known to have suffered an aneurysmal subarachnoid hemorrhage (SAH). Forty-three individuals (17%) were either found dead or were dead on arrival at a hospital or forensic department. Forty-nine patients (20%) were at no stage in their clinical course considered to be surgical candidates. Six patients (2% of the total series) were initially in good condition, but subsequently deteriorated during the acute phase and were not treated surgically. Nineteen poor-risk patients (8% of the total series) underwent emergency surgery because of a life-threatening intracerebral hematoma; 105 patients (42% of the total series or 69% of the surgically treated patients) were operated on at the acute stage, and 29 patients (11% of the total series or 19% of the surgically treated patients) underwent late surgery. Of the total series, 107 patients (42%) recovered without neurological deficits; the overall morbidity rate was 19%, and the mortality rate was 39%. Of 99 Grade I to III patients who were operated on at the acute stage, 76% recovered without neurological deficits, and 4% died. It is concluded that the overall outcome in aneurysmal SAH remains poor, mainly because of the large group of patients who are permanently devastated by their initial bleed.

Adult↗
PubMed1985

Cognitive impairment and adjustment in patients without neurological deficits after aneurysmal SAH and early operation.

The mortality rate has recently been reduced to only a small percentage of patients selected for early aneurysm surgery. Despite recovery without neurological deficits, however, a diffuse encephalopathy may remain, with emotional and psychological sequelae that will interfere with rehabilitation and social reintegration. The present study evaluates quality of life, degree of cognitive dysfunction, and adjustment of patients with a satisfactory neurological recovery after aneurysm operation in the acute stage following a major subarachnoid hemorrhage (SAH). Of 118 patients with a good neurological recovery, 40 patients were randomly sampled for a cross-sectional study and subjected to a questionnaire relating to their symptoms, a clinical interview, and a comprehensive neuropsychological investigation. The time interval between SAH and assessment varied between 14 months and 7 years, averaging 3 1/2 years. By means of standardized psychometric testing of intellectual capacity, memory functions, visuo-spatial abilities, perceptual speed and accuracy, and concept formation, degrees of cognitive impairment ranging from slight to severe dysfunction were identified. The results suggest that these disturbances may be permanent. The degree of impairment appeared to correlate with the patients' age. Interview data revealed substantial post-hemorrhagic maladjustment with respect to vitality, social management, self-assertion, emotional control, temperament, mood, and cognitive abilities. These findings were considerably at variance with the symptoms reported. It is stressed that, in the absence of gross neurological deficits, vital information on post-hemorrhage adjustment and impairment may easily be overlooked due to psychological defensive measures. It remains an open question whether post-SAH encephalopathy is enhanced by surgery performed in the acute stage.

Activities of Daily Living↗
PubMed1984

Aneurysmal subarachnoid hemorrhage--historical background from a Scandinavian horizon.

The historical background of aneurysmal subarachnoid hemorrhage is depicted with emphasis in the Scandinavian contribution to improvements in the treatment. It is concluded that an aneurysmal subarachnoid hemorrhage with all certainty was the cause of death of the prospective King of Sweden, Charles August, in the year 1810. Despite advances in management and surgical treatment of this devastating disease the outcome in this important patient--which led to a new royal dynasty in Sweden--would certainly have turned out as fatal today as became the case 174 years ago.

England↗
PubMed1984

Characterization of the prostanoid receptors and of the contractile effects of prostaglandin F2 alpha in human pial arteries.

The contractile and relaxant effects of various prostanoids were studied on isolated human pial arteries. Contractions were elicited with the following order of potency: U46619 approximately equal to U44069 greater than PGB2 greater than PGF2 alpha greater than PGE2 approximately equal to PGD2 approximately equal to PGF1 alpha greater than or equal to TXB2, indicating that prostanoid-induced contractions probably are mediated by a thromboxane-sensitive receptor. Relaxation of PGF2 alpha-contracted arteries was induced with the order of potency: PGE2 greater than PGE1 greater than PGD2 approximately equal to PGD1. Vessels contrated by K+ were relaxed only by PGE1. Since PGI2 was previously found to be more potent than all the prostanoids tested in the present study, relaxant responses are probably mediated via a PGI2-sensitive receptor. The role of free extracellular and cellularly bound calcium for the contractile effects of PGF2 alpha and K+ were estimated by incubating the arteries for various times in calcium-free medium containing 10(-5) M EGTA. Incubation for 5-10 min abolished K+-induced contractions, whereas after 40 min of incubation PGF2 alpha still induced contractions that reached 70% of control. The PGF2 alpha-induced contraction was biphasic in 8 out of 10 preparations. The second phase could be eliminated by increasing the EGTA-concentration to 10(-4) M, as well as by nifedipine pretreatment. In calcium-free, high K+ medium calcium-induced contractions were elicited at lower concentrations in the presence of PGF2 alpha. The results suggest that PGF2 alpha-induced contractions in human pial arteries are relatively independent of free extracellular calcium. PGF2 alpha may promote trans-membrane influx of calcium, as well as release calcium from seemingly superficially located cellular stores.

Calcium↗
PubMed1984

Early aneurysm operation and outcome in two remote Scandinavian populations.

The Kuopio University Clinic is the neurosurgical referral center for a population of 930,000 inhabitants in central Finland while the Lund University Clinic is the neurosurgical referral center for a population of 1.46 million inhabitants in southern Sweden. The incidence of aneurysmal subarachnoid hemorrhage (SAH) is approximately 19/100,000/year in central Finland and approximately five/100,000/year in southern Sweden. During the calendar year 1982, 69 patients with a ruptured supratentorial aneurysm were admitted in Lund, and 71 such patients were admitted in Kuopio. Thirty-nine patients in neurological Grades I to III (according to Hunt and Hess) underwent early aneurysm operation in Lund, and 46 such patients were operated on within a week after SAH in Kuopio. In the combined series of 85 Grade I to III patients with aneurysm operation within a week after rupture, 78% made a good recovery; the morbidity rate was 14%, and the mortality rate was 8%.

Adult↗
PubMed1984

Outcome in 60 consecutive patients treated with early aneurysm operation and intravenous nimodipine.

Sixty consecutive patients with a ruptured supratentorial aneurysm underwent operation during the acute stage, 56 of them within 72 hours after the first bleed, one on the 4th day, and three on the 5th day. Six patients were classified preoperatively in Hunt and Hess neurological Grade I, 39 in Grade II, 11 in Grade III, and four in Grade IV or V. Nine patients had severe intracerebral hematomas, and one patient had a subdural hematoma. After the aneurysm was clipped, nimodipine was applied to the exposed arterial segments in a 2.5 X 10(-5)M solution for 10 minutes. Subsequently, all patients received a continuous intravenous nimodipine infusion (2 mg/hr) for 7 to 12 days, followed by oral treatment (270 mg/day). Forty-six patients (77%) made a good neurological recovery; the morbidity rate was 22%, and mortality rate 1.5%. Of the 45 patients in good condition (Grades I to II) preoperatively, 38 (84%) made a good neurological recovery. Two patients (3% of the total series) developed a typical picture of cerebral ischemic dysfunction of delayed onset with subsequent fixed neurological deficits. The results favor the opinion that early operative intervention is beneficial in patients in good condition rather than delaying surgery, and indicate that nimodipine provides an additional anti-ischemic effect. The appearance and severity of late angiographic vasospasm did not seem to be affected by nimodipine.

Adult↗
PubMed1983

Immunoglobulin-A producing probably primary lymphoma of the breast.

A breast tumour from a 65-year old woman was found to be a primary non-Hodgkin lymphoma, a very rare primary malignancy in this location. The lymphoma was of a diffuse histiocytic type according to the classification of Rappaport, or polymorphic immunocytoma according to the Kiel classification. Immunohistochemistry, not previously reported for breast lymphomas, revealed the production of IgA. In the serum this appeared as an IgA M-component which was greatly reduced after tumour removal. Immunological properties of primary breast lymphomas are reviewed, we suggest further extended studies with the immunohistochemical use of marker substances for the evaluation of prognosis.

Aged↗
PubMed1983

Variations between individuals in cerebrovascular responsiveness.

1. Despite extensive research no explanation has been put forward to account for the fact that cerebral arterial spasm complicates the course of disease of many but not all patients suffering from rupture of an intracranial aneurysm. Although vasoactive material in hemorrhagic cerebrospinal fluid (CSF) most probably is of major importance in the pathophysiology of delayed cerebral vasospasm, recent studies have failed to demonstrate a correlation between CSF vasoconstrictor activity and the development of delayed cerebral vasospasm. 2. In the present study the reactivity of isolated human pial arteries to various vasoactive agents [prostaglandin F2 alpha, noradrenaline, serotonin, human plasma and CSF from patients with aneurysmal subarachnoid hemorrhage (SAH)] was investigated. 3. There was a very marked variability in the spectrum of responses between arteries from different individuals with regard to the contractile responses to plasma, hemorrhagic CSF and amines. On the other hand, the contractions produced by prostaglandin F2 alpha and potassium were consistent. 4. The markedly individual profile in terms of reactivity toward vasoactive substances emphasizes the importance of a human cerebral vessel wall factor and may explain the capricious occurrence of cerebral vasospasm after aneurysmal SAH.

Adult↗
PubMed1983

Prostaglandin metabolism and prostacyclin in cerebral vasospasm.

1. Contractions of isolated human pial arteries, induced either by exposition to hemorrhagic cerebrospinal fluid (CSF) from patients with subarachnoid hemorrhage and cerebral vasospasm or by exposition to noradrenaline, were markedly augmented after preincubation of the vessel segments with the cyclooxygenase inhibitor indomethacin, while serotonin-induced contractions were unaffected. 2. Prostacyclin relaxed human pial arteries contracted by either PGF2 alpha, noradrenaline, serotonin or hemorrhagic CSF. The same though less marked effects were obtained with 6-keto-PGE1. 3. The results support the contention that an intact vascular prostacyclin synthesis is important for the maintenance of a normal cerebrovascular tone, and that disturbances of the prostaglandin metabolism may be a prerequisite for the development of arterial spasm after aneurysmal subarachnoid hemorrhage. Tentatively. 4. a prostacyclin deficiency may be involved in the pathogenesis of delayed cerebral vasospasm after subarachnoid hemorrhage.

Alprostadil↗
PubMed1983

Responses of isolated feline and human cerebral arteries to prostacyclin and some of its metabolites.

The effects of prostacyclin (PGI2) were studied in isolated cat basilar and middle cerebral arteries and in human pial arteries. In feline vessels with low resting tension, PGI2 had a contractile effect that reached a maximum of 132% (basilar artery) and 23% (middle cerebral artery) of the potassium-induced (127 mM) contraction. In potassium-contracted feline vessels, PGI2 caused a further contraction. When these vessels were contracted by PGF2 alpha, PGI2 induced relaxation, which was most marked in the middle cerebral artery. PGI2 consistently relaxed the middle cerebral artery contracted by the prostaglandin endoperoxide analogue U-44069, whereas the basilar artery was almost unaffected. In human pial arteries with low resting tension, PGI2 had no effects in concentrations below 10(-6) M, whereas higher concentrations induced contractions. In potassium-contracted (35 or 127 mM) preparations, PGI2 in concentrations below 10(-6) M produced relaxation; in higher concentrations further contraction was induced. Human pial arteries contracted by PGF2 alpha, U-44069, noradrenaline, or 5-hydroxytryptamine consistently relaxed in response to PGI2 (less than 10(-6) M). The PGI2 metabolite 6-keto-PGE1 had effects similar to those of PGI2, but proved to be less potent on human pial vessels. 6-Keto-PGF1 alpha was ineffective, whereas 6,15-diketo-PGF1 alpha had minor relaxant effects. The results suggest that consideration must be given to regional as well as species differences concerning the cerebrovascular effects of PGI2.

6-Ketoprostaglandin F1 alpha↗