Efferent Pattern of Fictive Locomotion in the Cat Forelimb: with Special Reference to Radial Motor Nuclei.

In immobilized decerebrate cats fictive locomotion was evoked by midbrain stimulation to analyse the efferent pattern to elbow and to distal forelimb muscles innervated by the deep radial nerve. The locomotor activity was assessed by recording nerve discharges and motoneuronal membrane potential changes. The elbow flexor and extensor motoneurons showed a reciprocal activity; the membranes were correspondingly depolarized and hyperpolarized. In the motor nuclei to the wrist and digit extensors the active phases changed systematically according to the radio-ulnar order of the muscles: the extensor carpi radialis (ECR) was flexor-coupled, the ulnaris (ECU) extensor-coupled, the digitorum communis (EDC), the lateralis (EDL) and the indicis proprius (EIP) displayed intermediate patterns. Intracellular recordings from these motoneurons revealed in all motor nuclei, except ECR, a double depolarization. The first occurred early and the second later in the flexor phase; a hyperpolarization was interposed. The second depolarization mainly determined the active phase. According to the radio-ulnar order of the muscles the onset and termination of the second depolarization were delayed. This was presumably due to the interposed hyperpolarization, which progressively increased in amplitude. The ECR exhibited a single depolarization, into which the double depolarization apparently merged. The other radial motor nuclei, supinator (Sup) and Abductor pollicis longus (APL) displayed complex patterns. Sup showed tonic discharges, flexor-type discharges or discharges extending both into the flexor and extensor phase, APL showed discharges similar to either EIP or Sup. Membrane potential changes were small in APL and Sup. Thus, the central locomotor network generates differentiated efferent activities in the distal forelimb muscles, the radio-ulnar order of the muscles being important for the generated pattern.

Family history of hypertension and cardiovascular reactivity to mental stress--effects of stimulus intensity and environment.

Normotensives with hypertensive parents have been reported to exhibit enhanced cardiovascular reactions to mental stress. We have examined the question of why this result was not confirmed in all studies. In addition we have investigated whether appropriate tests can be performed under clinical rather than laboratory conditions. Healthy male subjects were examined. In experiment I, under laboratory conditions, a standard stress test was intensified (n = 30). In experiment II the same test was used in a simplified version which did not require special equipment (n = 19). Blood pressure, heart rate and stroke volume (by impedance cardiography) were measured. In contrast to the results with the standard test, subjects with at least one hypertensive parent exhibited enhanced responses of systolic and diastolic blood pressure and heart rate. We conclude that cardiovascular hyper-reactivity in subjects with hypertensive parents is only apparent using sufficiently intense stimuli. Although less pronounced, these differences can also be observed under clinical conditions.

[Duplex ultrasound of the liver and portal vein system]. / Die Duplexsonographie der Leber und des Pfortadersystems.

Duplex ultrasound allows direct access to portal venous and hepatic vein hemodynamics. This method has been accepted as a reliable procedure to detect portal and splenic venous thrombosis, Budd-Chiari's syndrome, portosystemic collateralisation and changes in the portal venous blood flow direction with a high rate of sensitivity. Besides these qualitative findings Doppler flowmetry allows quantitative measurement of portal venous blood flow velocities. The estimation of portal hypertension and the prediction of the risk of variceal bleeding by quantitative Doppler flowmetry is of increasing clinical importance. In monitoring the efficiency of medicational prophylaxis against gastrointestinal bleeding is also helpful. Duplex ultrasound can be used to evaluate the function of portocaval shunts including the intrahepatic stent shunt as well as to detect vascular complications after liver transplantation. Furthermore the method is gaining importance in the diagnosis and monitoring of therapy of acute liver transplant rejection. In case of liver tumors duplex ultrasound is of value for tumor staging and provides information about the dignity on the basis of perfusion patterns.

[Spondylogenic psoas abscess: long-term follow-up after percutaneous drainage]. / Spondylogener Psoasabszess: Langzeitverlauf nach perkutaner Drainage.

Iliopsoas abscesses originating from bacterial lumbar spondylodiscitis were successfully treated by CT-guided percutaneous abscess drainage, antibiotics, and immobilization in two patients. Vertebral fusion of the affected segments was observed in both patients in the follow-up period (1 and 6 years, respectively). Percutaneous abscess drainage can replace surgery for iliopsoas abscesses following vertebral osteomyelitis.

[Duplex sonographic studies on the pathogenesis of splenic hemodynamics in liver cirrhosis]. / Duplexsonographische Untersuchungen zur Pathogenese der lienalen Hämodynamik bei Leberzirrhose.

AIM OF STUDY: The haemodynamic role of the spleen in portal hypertension remains unclear. Duplex sonography was undertaken prospectively to discover the relationship of splenomegaly and splenic vein flow to type and severity of liver cirrhosis and portal vein flow, as well as to the degree of oesophageal varices. PATIENTS AND METHODS: 89 patients (54 men, 35 women; mean age 52 [26-81] years), diagnosed in the second half of 1993 as having liver cirrhosis were consecutively included in the study. In 40 patients the cirrhosis was in stage A (according to Child-Pugh classification), in 31 in stage B and in 18 in stage C. RESULTS: Portal vein flow fell significantly with increasing degree of cirrhosis (stage A: 8.29 cm/s; stage B 7.03 cm/s; stage C 5.26 cm/s; P < 0.05). Splenic vein flow differed significantly only between stages B and C (stage A: 9.22 cm/s; stage B: 9.46 cm/s; stage C: 7.87 cm/s; B vs C, P < 0.05). There was no correlation between portal vein flow, splenic vein flow, degree of splenomegaly and extent of oesophageal varices. CONCLUSION: The results may be explained by the presence of collateral circulations and by the differing pathophysiological part played by the spleen in liver cirrhosis of different aetiologies.

Weekly oxaliplatin, high-dose infusional 5-fluorouracil and folinic acid as palliative third-line therapy of advanced colorectal carcinoma.

The efficacy of oxaliplatin combined with high-dose 5-fluorouracil (5-FU) and folinic acid (FA) as an outpatient salvage treatment for patients with metastasized colorectal cancer was retrospectively analyzed in one center. Tumor progression had occurred for the majority of patients during two regimens (n = 11) otherwise during one (n = 1) regimen of prior 5-FU-based chemotherapy, which had been applied in a standardized sequential fashion. As third-line therapy oxaliplatin was infused intravenously over 2 h at a dose of 60 mg/m2 prior to a 2-h infusion of FA (500 mg/m2). 5-FU (2,600 mg/m2) was subsequently given over 24 h. A favorable response was observed in 9/12 (75%) of the heavily pretreated patients, including partial remissions in 3/12, minor responses in 2/12 and stable disease in 4/12 patients. The median progression free time was 23 weeks (interquartile range i. r. 0-28) for all patients, the median survival time from start of third-line therapy 55 weeks (i. r. 40-86). The median survival time from the beginning of first-line palliative chemotherapy was 34 months (i. r. 25-45 months). The highest toxicity was WHO grade III and was observed in six patients: Nausea (2), diarrhea (3), vomiting (2) and peripheral neuropathy (1). The quality of life was not adversely affected by the oxaliplatin/5-FU/FA-regimen as assessed by the EORTC QLQ-C30 questionnaire. Thus, the results show the efficiency and low toxicity of oxaliplatin/high-dose 5-FU/FA as palliative third-line therapy of patients with metastasized colorectal cancer and emphasize that sequential palliative chemotherapy may lead to extended survival of these patients.

Mixed cryoglobulinemia type II in chronic hepatitis B associated with HBe-minus HBV mutant: cellular immune reactions and response to interferon treatment.

The case of a young female patient with chronic active hepatitis B, vasculitic purpura, edema, and circulating immune complexes due to mixed cryoglobulinemia is described. Serum transaminases were elevated. Serological assays showed hepatitis B surface antigen (HBsAg), antibody to hepatitis B e antigen (anti-HBe), and antibody to hepatitis B core antigen (anti-HBc) antibodies but no antibody to hepatitis C virus (anti-HCV) or antibody to hepatitis delta virus (anti-HDV) antibodies. Using hepatitis B virus-polymerase chain reaction (HBV-PCR) and direct sequencing a precore/core (preC/C) mutant unable to synthesize HBeAg was detected in serum. HBV antigens were demonstrated in the circulating immune complexes. Following 1 month of treatment with interferon-alpha 2b3 miu three times weekly, alanine aminotransferases returned to normal levels while cryoglobulins and immune complexes disappeared from serum. In addition, 2 months after the onset of treatment serum HBV-DNA was no longer detectable by PCR. Prior to treatment the analysis of cellular immune reactions of peripheral blood mononuclear cells showed a major proliferative response to HBcAg, preS1Ag and HBxAg and a minor response to HBeAg and HBsAg. One month after conclusion of treatment a decline in T-cell reactivity against all HBV antigens was observed. During clinical response to the therapy, however, a strong proliferative response of T cells to HBcAg and HBeAg was demonstrated. In conclusion, immune complex disease may complicate chronic hepatitis B in patients expressing HBe-minus HBV mutants. Treatment with interferon-alpha was found to be effective in mixed cryoglobulinemia even in the presence of HBe-minus HBV mutants.(ABSTRACT TRUNCATED AT 250 WORDS)

Posttransfusional, LKM-1-autoantibody-positive hepatitis C virus infection, cryoglobulinemia, and aplastic anemia.

Aplastic anemia is occasionally caused by viral hepatitis, hepatitis C virus being the most important factor. Pathogenetically, decreased bone marrow function, abnormalities of the bone marrow microenvironment, and immune-mediated suppression of hematopoiesis are important. Hepatitis C virus infection is associated with a variety of extrahepatic manifestations including autoimmune features like cryoglobulinemia, Sjögren's syndrome, and autoimmune hepatitis. Here we report the case of a 42-year-old man with aplastic anemia due to posttransfusional hepatitis C virus infection associated with cryoglobulinemia and LKM-1 autoantibodies. Following a triple immunosuppressive therapy, there was a complete reconstitution of the bone marrow. Serum HCV-RNA as well as plus- and minus-stranded HCV-RNA in peripheral blood mononuclear cells (PBMC) were detected before immunosuppressive therapy. After therapy, serum HCV-RNA persisted. Furthermore, PBMC now were positive for plus-stranded RNA only. However, in bone marrow-derived precursor cells we failed to demonstrate HCV molecules after therapy. This would argue for reconstituted PBMC from newly generated uninfected precursor cells. It remains unclear as to whether the autoimmune character of the disease or the hepatitis C virus infection itself have contributed to the pathogenesis of the aplastic anemia.