Impairment of the postural venoarteriolar response in young type 1 diabetic patients. A study by laser doppler flowmetry.

The skin blood flow and venoarteriolar response (VAR) in the feet of the young type 1 diabetic patients were studied with laser Doppler flowmetery. The findings were correlated with diabetic microangiopathy in 24 young patients without neuropathy--14 with diabetic microangiopathy, 10 without--and 10 healthy controls. In type 1 diabetic patients and skin blood flow, after lowering of the leg, was significantly higher in the microangiopathic patients than in the healthy controls, 5.

Expression of fibrinolytic genes in atherosclerotic abdominal aortic aneurysm wall. A possible mechanism for aneurysm expansion.

Expansion of atherosclerotic abdominal aortic aneurysm (AAA) has been attributed to remodeling of the extracellular matrix by active proteolysis. We used in situ hybridization to analyze the expression of fibrinolytic genes in aneurysm wall from eight AAA patients. All specimens exhibited specific areas of inflammatory infiltrates with macrophage-like cells expressing urokinase-type plasminogen activator (u-PA) and tissue-type PA (t-PA) mRNA.

Modulation of the fibrinolytic system by major peripheral ischemia.

Purpose: A rat model was developed to investigate the effects of acute peripheral ischemia on the components of the fibrinolytic system.

Methods: Laparotomy was performed and ischemia was introduced by total aortic clamping at a subrenal position. Control animals underwent sham laparotomy alone.

Hippocampal plasticity following epileptiform bursting produced by GABAA antagonists.

The effects of epileptiform bursts on hippocampal excitability were examined in the CA3 region of guinea-pig hippocampal slices. Partial blockade of gamma-aminobutyric acidA (GABAA)-mediated inhibition by 500 IU/ml penicillin produced low frequency (2-4 Hz) "pro-convulsant" field potential oscillations. Normal spontaneous activity recovered less than 30 min after the penicillin was rinsed out providing bursting was prevented.

The role of excitatory amino acids in the generation of spontaneous hippocampal oscillations.

We examined the role of N-methyl-D-aspartate (NMDA) and non-NMDA glutamate receptors in generating spontaneous CA3 field potential oscillations in the hippocampal slice. Non-NMDA EPSPs are responsible for a portion of the spontaneous activity recorded in standard perfusion medium. NMDA receptors are not activated when inhibition is intact, however, recurrent excitation via NMDA receptors accounts for an increasing proportion of the low frequency (2-4 Hz) rhythms produced as inhibition is progressively blocked by low concentrations of the GABAA antagonist, penicillin.

Intra-arterial thrombolytic therapy: a combined approach with angioplasty and/or minor surgery.

Low-dose intra-arterial treatment was performed in 124 patients who underwent a total of 142 procedures. The series included 87 occluded arteries and 55 occluded grafts. In only 29 instances (21%) was thrombolysis alone sufficient.

Type 1 plasminogen activator inhibitor gene expression following partial hepatectomy.

A murine model of partial hepatectomy (PH) was employed to investigate type 1 plasminogen activator inhibitor (PAI-1) gene expression in regenerating liver. Mice were anesthetized, and a portion of the left lobe of the liver was ligated and resected distal to the ligature, and at various times thereafter, total liver RNA was prepared and analyzed by Northern blotting. PH caused a transient increase in PAI-1 messenger (m)RNA that was apparent within 1 to 2 hours after surgery, was maximal at 8 hours (ninefold increase over sham-operated controls), and then slowly declined.

Percutaneous transluminal aortic angioplasty: early and late results.

Percutaneous transluminal angioplasty of the infrarenal abdominal aorta (13 patients) and its bifurcation (15 patients) was performed in 28 patients with a total of 32 dilatation procedures. The group consisted of 16 female and 12 male patients and initial successful dilatation was achieved in all. Recurrence within 1 month requiring bypass surgery occurred in 1 patient.

Tissue factor localization in non-human primate cerebral tissue.

Tissue factor (TF), the principal procoagulant of human brain, resides in specific regions of the non-human primate central nervous system. Immunohistochemical studies employing murine anti-human TF monoclonal antibodies (MoAbs) detected TF antigen in the cortex, basal ganglia, cerebellum, and cervical spinal cord in three normal baboon subjects. Although significantly less prominent than human cortical gray matter, a distinct partition of TF in gray matter > white matter was noted.

Low concentrations of penicillin partially suppress CA3 hippocampal IPSPs in vitro.

Low concentrations of penicillin (50-300 IU/ml) produce a pro-convulsant state in CA3 hippocampus characterized by low amplitude, low frequency (2-3 Hz) spontaneous field potential oscillations. Evoked field potentials were used to demonstrate that this distinct, coordinated behavior of the hippocampal neuronal network which is intermediate between normal activity and fully synchronized epileptiform bursting is the result of partial blockade of GABAA-mediated IPSPs. A new method for estimating the degree of IPSP block relative to convulsant doses of penicillin (2,000 IU/ml) indicates that the half-maximal effect occurs at 300 IU/ml.

Increased type 1 plasminogen activator inhibitor gene expression in atherosclerotic human arteries.

Decreased fibrinolytic capacity has been suggested to accelerate the process of arterial atherogenesis by facilitating thrombosis and fibrin deposition within developing atherosclerotic lesions. Type 1 plasminogen activator inhibitor (PAI-1) is the primary inhibitor of tissue-type plasminogen activator and has been found to be increased in a number of clinical conditions generally defined as prothrombotic. To investigate the potential role of this inhibitor in atherosclerosis, we examined the expression of PAI-1 mRNA in segments of 11 severely diseased and 5 relatively normal human arteries obtained from 16 different patients undergoing reconstructive surgery for aortic occlusive or aneurysmal disease.

Autoimmune mechanisms in thromboangiitis obliterans (Buerger's disease): the role of tobacco antigen and the major histocompatibility complex.

This study is a continuation of our previous work that showed that patients with thromboangiitis obliterans (TAO; Buerger's disease) demonstrate a cell-mediated immune response to human artery type-specific collagens. To investigate the role of cigarette smoking in patients with TAO, cellular and humoral sensitivity was tested to a tobacco glycoprotein (TGP) antigen in 13 patients with Buerger's disease, 16 healthy smokers, and 12 nonsmoking healthy young male subjects. In this study, patients with Buerger's disease and healthy smokers had the same rate of cellular response to TGP, whereas nonsmokers did not respond.

Comparative drug effects and abuse liability of lorazepam, buspirone, and secobarbital in nondependent subjects.

The pharmacologic effects of lorazepam (2 mg), buspirone (20 mg, 10 mg), secobarbital (100 mg), and placebo were compared in 15 male, experienced, intermittent nontherapeutic drug users. All drugs produced a "drug effect," however, buspirone 20 mg was significantly less liked than were lorazepam, secobarbital, or buspirone 10 mg (p less than .05) but not placebo.

Evoked CA3 field potentials corresponding to both EPSPs and IPSPs in hippocampal slice.

Biphasic field potentials were recorded in the CA3 distal dendritic region in response to both antidromic (fornix) and orthodromic (mossy fiber) stimulation in guinea pig hippocampal slices in vitro. The positive component (P1) corresponded to intracellularly recorded excitatory postsynaptic potentials. The negative component (N1) appears to be due to GABAA-mediated inhibitory postsynaptic potentials (IPSPs) since it corresponded to the fast IPSP recorded intracellularly, was blocked by bicuculline and penicillin and augmented by barbiturates.

Accumulation of cocaine in maternal and fetal hair; the dose response curve.

Cocaine and its major metabolites are incorporated into hair during the growth of the shaft and stay there for the whole life of the hair. Cocaine crosses the placenta and its metabolites for example Benzoylecgonine (BZ), have been found in neonatal urine, meconium and hair. In order to utilize hair measurements of cocaine as a biological marker of systemic exposure, we conducted both animal and human investigations on the dose response characteristics of this phenomenon.

Pulse volume recording disturbances in paraplegic patients.

Spinal cord injuries may modify vascular reactivity in the denervated region. This study presents an original observation of altered vascular response in paraplegic patients. A group of 30 consecutive paraplegic otherwise normal individuals underwent a thorough vascular examination.

Biochemical analysis of a human humoral fibroblast inhibitory factor associated with impaired vascular prosthetic graft incorporation.

A specific inhibitory factor was isolated from human serum of a patient who manifested impaired prosthetic graft tissue incorporation. The latter reaction was hypothesized to be related to inhibiting fibroblast proliferation by a specific humoral factor. The crude inhibitory serum was tested against a pool of normal human sera with different cell types in culture.

Changes in plasmatic tissue-type plasminogen activator and plasminogen activator inhibitor activity during acute arterial occlusion associated with severe ischemia.

Severe lower limb ischemia in patients with acute arterial occlusion was associated with a significant increase in systemic fibrinolytic activity. Plasmatic level of t-PA activity was twice the normal value at the peak of ischemia. This level declined gradually within no less than 40 hours after reperfusion procedure or limb amputation had reverted the ischemic state.

Methanol poisoning: bilateral putaminal and cerebellar cortical lesions on CT and MR.

Bilateral putaminal necrosis is often recognized radiologically in severe methanol toxicity. We present a unique case of methanol toxicity in which putaminal and previously unreported bilateral cerebellar cortical lesions were demonstrable on CT and MR.

Plasminogen activator inhibitors.

Plasminogen activator inhibitors (PAIs) regulate plasminogen activation in normal and pathologic processes. Plasminogen activator inhibitor 1 (PAI-1) is the major physiologic inhibitor of both tissue-type and urokinase-type plasminogen activators. It is a highly regulated single-chain glycoprotein, whose overexpression in vivo impairs the fibrinolytic balance and correlates with thrombotic disorders.

[Surgery for thoraco-abdominal aortic aneurysm].

12 patients underwent resection of a thoraco-abdominal aortic aneurysm. There were 10 men and 2 women, ranging in age from 54-78 years (mean 65). Aortic arteriosclerosis was the primary etiology in 11, and Behcet's disease in the other 1.

Actions of ketamine, phencyclidine and MK-801 on NMDA receptor currents in cultured mouse hippocampal neurones.

1. Stable N-methyl-D-aspartic acid (NMDA) receptor-mediated currents in cultured mouse hippocampal neurons were evoked by 20 ms pressure pulse applications of L-aspartate, repeatedly applied at 30 or 40 s intervals, to the cell body region of the neurone. We have characterized the voltage- and use-dependent blockade of the currents by three dissociative anaesthetics: ketamine, phencyclidine (PCP) and MK-801 in mouse hippocampal neurones grown in dissociated tissue culture.