Amplitudes of visually evoked cortical responses due to full-field stimulation and to stimulation with four half-fields

In 30 healthy subjects the VECP following full-fields, upper, lower, nasal and temporal half-field stimulation was recorded. The full-field amplitudes is significantly larger than each of the half-field responses. For peak P120, the amplitudes following lower half-field stimulation is significantly larger than the amplitude due to upper, nasal and temporal half-field stimulation. The sum two half-field amplitude is significantly larger than the full-field response.

[Blocking of S2 receptors--a new treatment principle in generalized tendomyopathy (fibromyalgia)?]

In a pilot study, the effectiveness of the S2-receptor blocker ketanserin was investigated in patients receiving concurrent physiotherapy for primary fibromyalgia. This combined treatment was compared with physiotherapy alone. In the group treated with ketanserin, a significant reduction in spontaneous pain was observed, and the painfulness of "tender points" also decreased markedly. The patients experienced a significant improvement in the quality of sleep, the feeling of being rested after sleep, and psychological well-being in the evening. Significant improvement was also recorded on the Zerssen Mood Scale and the Erlanger Anxiety Scale. In the group receiving physiotherapy alone, the improvements were far less marked and usually were below the significance level. These results are now being verified in a double-blind, randomized trial.

[Time resolved laser fluorescence microscopy of hematoporphyrin derivative in vivo]

Laser-assisted fluorescence microscopy proved a powerful method for quantitative in vivo measurement of HpD fluorescence. Therefore the aim of the present work was to study the distribution of HpD in tumor vs. adjacent tumor-free tissue of 10 animals over a period of 8 days. We measured additionally the differences in HpD uptake in different tumor subcompartments. In tumor tissue HpD fluorescence showed maximum values 5-9 hours after i.v. application of the drug. The relation tumor-free tissue at that time was about 3-8. The third day of examination showed nearly identical values for both tissues. Between day 5 and day 8 we found an increase of HpD contents in tumor vs. normal tissue in 50% of the examined animals. Comparative measurements in the tumor centre and the tumor edge showed a preferential uptake of HpD in the tumor edge area. Probably the higher retention of HpD in this area is due to the oedema zone surrounding the tumor and to extravasation of HpD.

Picrotoxin- and 4-aminopyridine-induced activity in hilar neurons in the guinea pig hippocampal slice

1. Paired extra- and intracellular recording was used to study the activity of neurons in the dentate hilus and their interaction with CA3/CA4 pyramidal neurons and granule cells during picrotoxin- or 4-aminopyridine (4-AP)-induced rhythmical activity in the guinea pig hippocampal slice. 2. Picrotoxin induced synchronous repetitive population spikes in the CA3, CA4, and hilar region, but no extracellular activity in the granule cell layer. 4-AP induced rhythmically occurring positive field-potential waves in the CA3, CA4, and granular layer coincident to negative/positive field potentials in the hilus. 3. Picrotoxin-induced activity originated in the CA3 area and subsequently appeared in the CA4 and hilar region, whereas 4-AP-induced activity appeared simultaneously in all subfields. 4. Blockade of fast glutamatergic excitation by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, 10 microM) blocked the picrotoxin-induced activity but not the 4-AP-induced activity. 5. Focal application of tetrodotoxin (TTX) between area CA3 and CA4 blocked picrotoxin-induced activity in the CA4 and hilar region but decoupled 4-AP-induced activity in the CA3 area. 6. Under intracellular recording, picrotoxin induced bursts in CA3, CA4, and hilar neurons but K-dependent slow IPSPs in granule cells. 4-AP induced rhythmically occurring burst in hilar neurons synchronous to Cl- and K-dependent IPSPs in CA3, CA4, and granule cells. 7. Comparison of picrotoxin- and 4-AP-induced rhythmical burst activity reveals that many hilar neurons are excited by CA3/CA4 pyramidal neurons in addition to the well-known excitation by granule cells and perforant path fibers, and that, in turn, many hilar neurons inhibit CA3, CA4, and granule cells.

A delta pH clamp method for analysis of steady-state kinetics of photophosphorylation

An instrumental device is described which allows steady-state kinetic measurements of photophosphorylation at a desired proton gradient which can be maintained throughout the course of the experiment ('delta pH clamp'). This is achieved by electronic regulation of light intensity using the calibrated 9-aminoacridine fluorescence signal as sensor of the gradient. The instrument is suitable for determination of kinetic parameters of the proton-translocating ATPase in isolated envelope-free chloroplasts under defined conditions. At clamped delta pH, phosphorylation as a function of substrate concentration shows Michaelis-Menten kinetics. The true Michaelis constants and the dissociation constants for phosphate and ADP are reported. The Michaelis constants are not affected by the magnitude of the proton gradient in the investigated range. The significance of these results is discussed.

Photodynamic therapy in head and neck surgery

The results of a clinical study of photodynamic therapy (PDT) on early stage cancer in head and neck surgery are presented in this report. 30 patients with T1 malignancies of the face and oropharynx have been treated primarily with PDT. After the longest follow up of 14 months two patients revealed recurrence of the disease or residual tumor, two patients have been retreated because of residual dysplastic cells in the control biopsy, and all other patients stay histologically proven free of disease. Hence, PDT appears to be a promising cancer treatment for different histological tumors that penetrate the host tissue definitely less than a laser beam of 630 nm, which is the appropriate wavelength for PDT. Deeper-penetrating malignomas may be accessable for PDT using insertable filters when applying interstitial laser light.

[Rheumatic manifestations in HIV infection]

The two main rheumatic manifestations of infection by human immunodeficiency virus (HIV) are arthropathies and autoimmune diseases. The pathogenesis of the rheumatic manifestations is currently undefined. Among the different mechanisms implicated, the severe immunosuppression and immunodysregulation, as well as recurrent infections are possible. A direct infection by HIV is another mechanism. The course of some rheumatic diseases may be altered by HIV-infection. Remission of rheumatoid arthritis during the course of HIV-infection is anecdotally reported in the literature, whereas patients with Reiter's syndrome seem to have a severe clinical course.

Absence of genotoxic activity of penbutolol in bacterial and mammalian cell screening systems

The genotoxic potential of the beta-adrenergic blocker penbutolol was assessed using the Ames and HGPRT tests, unscheduled DNA synthesis (UDS) and alkaline elution assays. In the Ames test, penbutolol was tested for cytotoxicity and genotoxic activity in concentration ranges of 0.8-500 micrograms/plate and 0.1-125 micrograms/ml in the HGPRT, UDS and alkaline elution assays. In the Ames test penbutolol showed significant toxicity above 500 micrograms/plate. In the mammalian cells (V79) used for the HGPRT test and A459 cells used for alkaline elution and UDS assays, penbutolol was cytotoxic at concentrations above 30 micrograms/ml. In another series of experiments, male Wistar rats were treated i.p. with penbutolol (1, 10 and 100 mg/kg) and after 2 h liver nuclei were isolated and formation of single DNA-strand breaks was measured. The results of the present study demonstrate the absence of genotoxic activity of penbutolol in the 5 strains of Salmonella typhimurium (TA98, TA100, TA1535, TA1537 and TA1538) and in the strain of Escherichia coli WP2 uvrA in the presence or absence of metabolic activation. In V79 cells, penbutolol showed no mutagenic effects at the HGPRT locus in the presence or absence of metabolic activation. Additionally, no significant incorporation of [3H]thymidine into the DNA in the UDS test or formation of DNA-strand breaks in the alkaline elution assay was detected in the non-toxic concentration range of penbutolol with or without metabolic activation. Furthermore, penbutolol did not cause DNA damage in liver nuclei isolated from penbutolol-treated rats.

[Site and incidence of multiple cancers in patients with squamous cell carcinomas of the upper aerodigestive tract]

The etiology of multiple primary cancers has not been clearly elucidated, although some pathogenic factors are known. The studies reported here include 796 patients who, between January 1970 and March 1989, presented with a carcinoma of the upper aerodigestive system. The charts of 687 patients were analyzed retrospectively; 109 patients were studied prospectively by systematic pretherapeutic panendoscopy. Multiple primary cancers were found in 76 cases (9.5%), 33 patients had synchronous cancers, and 43 had metachronous cancers. In the prospective study, the incidence of multiple cancers was higher (13.7%) than in the retrospective group (8.8%). Synchronous primaries were more frequent in the prospective study (8.2%) than in the retrospective analysis (3.4%). Second primaries were mostly found in the esophagus, the hypopharynx, the buccal cavity, and the lung. The authors also examined whether the anatomic location of the second primary cancer can be related to the site of the first. The five-year survival rate among patients with synchronous cancers (18%) was lower than among patients with metachronous cancers (41%). The prognosis for synchronous cancers deteriorates if the planned treatment has to be modified following the discovery of a second primary. Systematic pretherapeutic panendoscopy should be used to help detect early asymptomatic second primaries which might be missed during clinical examination.

Differential antagonism by 1,3-dipropylxanthine-8-cyclopentylxanthine and 9-chloro-2-(2-furanyl)-5,6-dihydro-1,2,4-triazolo(1,5-c)quinazolin-5-im ine of the effects of adenosine derivatives in the presence of isoprenaline on contractile response and cyclic AMP content in cardiomyocytes. Evidence for the coexistence of A1- and A2-adenosine receptors on cardiomyocytes

The antagonism by the A1-adenosine receptor antagonist 1,3-dipropyl-8-cyclopentylxanthine (DPCPX) and the A2-adenosine receptor antagonist [9-chloro-2-(2-furanyl)-5,6-dihydro-1,2,4-triazolo (1,5-c)quinazolin-5-imine] (CGS 15943A) of the effects of the A1-adenosine receptor agonist (-)-N6-phenylisopropyladenosine (R-PIA) and the A2-adenosine receptor agonist 5'-N-ethyl-carboxamideadenosine (NECA) in the presence of isoprenaline on contractile response and cyclic AMP (cAMP) content in cardiomyocytes from guinea pig cardiac ventricles were studied. In electrically driven (1 Hz) guinea pig ventricular cardiomyocytes R-PIA concentration-dependently (0.0001-100 microM) reduced the stimulatory effects of isoprenaline (0.01 microM) on contractile response and on cAMP content. The A1-adenosine receptor antagonist DPCPX (0.3 microM) antagonized the effects of R-PIA on contractile reponse and on cAMP content, whereas the A2-adenosine receptor antagonist CGS 15943A (0.01 microM) was ineffective. NECA (0.0001-100 microM) reduced the effects of isoprenaline (0.01 microM) on contractile response to about the same extent as R-PIA. However, NECA did not change cAMP content. DPCPX (0.3 microM) antagonized the effects of NECA on contractile response and evoked a cAMP-increasing effect of NECA, which was 38% of the isoprenaline value at most. In contrast, CGS 15943A did not affect the reduction of contractile response induced by NECA, whereas CGS 15943A revealed a cAMP-decreasing effect of NECA (0.1-10 microM). This study provides functional evidence that both, cAMP-decreasing A1- and cAMP-increasing A2-adenosine receptors are present on ventricular cardiomyocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

[Procedures and results with preoperative individual AO reconstruction plates]

As a rule continuous bony defects of the mandible after tumour resection are temporarily bridged with the AO reconstruction plate. To precontour the plate, CT-scans of the mandible at a scale of 1:1 6 mm above and parallel to the inferior margin are needed. Corresponding layers further cranial show the anatomy of the chin. Using a lateral cephalograph, the mandibular angle and the length of the plate in the ascending ramus are measured. Using the CT-scans, the lateral cephalograph, a prebent template and a corresponding model of the mandible, the plate is bent into shape. Of the nineteen preshaped reconstruction plates implanted, eleven did not need any intraoperative adjustment. The other eight plates needed only slight modifications of contour. Preoperative bending of the reconstruction plate reduces the time taken for the operation, protects the material and the plate is precisely shaped.

High-performance liquid chromatographic determination of the H+/K+ ATPase inhibitor (BY 1023/SK&F 96,022) and its sulphone metabolite in serum or plasma by direct injection and fully automated pre-column sample clean-up

A fully automated high-performance liquid chromatographic method is described for the determination of the new H+/K+ ATPase inhibitor BY 1023/SK&F 96,022 and its major metabolite occurring in dog serum. The method uses direct sample injection of up to 200 microliters and a pre-column switching technique. In order to optimize the recovery, pre-column conditions were varied systematically with respect to the pH of the pre-column eluent, its buffering capacity and content of acetonitrile. Optimization resulted in near 100% recovery for both compounds, thus allowing the use of external standardization. The linearity range, precision and detection limits were determined and the method shown to be applicable to both serum and plasma. The method was applied to define the pharmacokinetics in dogs and humans.

[Precipitating factors for shunt insufficiency in post-hemorrhagic hydrocephalus in the premature infant]

Between January 1984 and March 1989 twenty-seven low birth weight infants (mean birth weight 1351 gm, mean gestational age 30 weeks) required shunts after development of a posthaemorrhagic hydrocephalus. Revision of the shunt occurred in 78% of the patients with a range of 1 to 11 revisions. Obstruction of the ventricular catheter was the main cause of mechanical complications that occurred in 75%. Preterm infants weighing less than 1000 gm revealed an enormous infection rate of 71%. Initial shunt placement in the first 8 weeks of life was more likely to need shunt revision (94%) than that placed at older age (44%). There was no difference between the type of shunt and percentage of shunt revision, but the Heyer-Schulte system in comparison with the Codman Uni shunt was more likely to have mechanical complications. Infants with Grade IV haemorrhage required the same percentage of revisions as those with Grade III haemorrhage. There was no association between preoperative therapy and the need for shunt revision. A great amount of erythrocytes and very low glucose levels in the preoperative CSF were more likely to predict shunt revision than predicted by the CSF protein.

[Tissue pO2 measurement in taut back musculature (m. erector spinae)]

Measurements with polarographic needle probes in fibromyalgic muscles (mm. erectores spinae) revealed an elevated mean tissue-pO2. The total mean tissue-pO2 in the patient group was significantly higher than that in the control group. Greater pathological tension in fibromyalgic muscles increases the mean tissue-pO2. The distribution of local tissue-pO2 values was normal; there was no evidence of small hypoxic areas in the muscle. The elevated tissue-pO2 in fibromyalgic muscles could either be explained by an increase in local blood flow or by disturbance of oxygen-utilization of the muscle cells. The mean tissue-pO2 in patients treated with NSAD was lower than in patients without this treatment. Myogelosises (i.e., circumscript tautness in muscles, that, contrary to fibromyalgic muscles, do not relax under general anesthesia) showed low tissue-pO2 values and even hypoxia in the core. In myogelosises, pain could be hypoxic in nature. However, in fibromyalgic muscles no evidence for hypoxia or hypoxia-related pain could be found.

Inhibitory role of dentate hilus neurons in guinea pig hippocampal slice

1. Current and voltage-clamp recording of CA3/CA4 pyramidal neurons, hilar neurons, and granule cells or pairs of these neurons were used to study the generation of Cl-dependent and K-dependent inhibitory postsynaptic potentials (IPSPs) in the guinea pig hippocampal slice preparation. 2. A sequence of an early Cl-dependent and a late K-dependent IPSP was evoked in CA3 neurons by electrical stimulation from the stratum moleculare of the dentate gyrus, the hilus, and the stratum oriens/alveus. Blockade of glutamatergic excitation by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, 10 microM) and D(-)-2-amino-5-phosphonovaleric acid (APV, 30 microM) abolished IPSPs evoked from the stratum moleculare of the dentate gyrus, but IPSPs could still be evoked from the hilus and the stratum oriens/alveus. 3. Repetitive giant IPSPs, which consisted of Cl-dependent and K-dependent components, were evoked by bath application of 4-aminopyridine (4-AP, 10-50 microM) in CA3 neurons and in granule cells. Giant IPSPs were blocked by bath-applied tetrodotoxin (TTX). In addition, 4-AP hyperpolarized CA3 neurons in a Cl-dependent and picrotoxin-sensitive way. 4. Focal application of TTX to the dentate gyrus or the hilus considerably reduced the amplitude of giant IPSPs evoked by 4-AP in CA3 neurons. In hilar neurons, 4-AP evoked repetitive bursts, eventually, but not necessarily intermingled with giant IPSPs. Bursts were observed in hilar neurons in presence as well as absence of CNQX and APV. 5. In paired recordings, bursts in hilar neurons induced by 4-AP occurred simultaneously to giant IPSPs in granule cells and CA3 neurons, and giant IPSPs in granule cells occurred simultaneously to giant IPSPs in CA3 neurons. Blockade of glutamatergic excitation by CNQX and APV did not abolish this synchrony. 6. 4-AP-evoked Cl- and K-dependent IPSPs were, unlike electrically evoked IPSPs, not strictly coupled: some 20% of large IPSPs and up to 90% of small IPSPs were either Cl or K dependent. In granule cells K-dependent components either preceded or followed Cl-dependent components. 7. K-dependent IPSPs only could be evoked in CA3 neurons by focal application of 4-AP (1 mM) to the hilus, the stratum lacunosum moleculare or the stratum pyramidale. Wash out of Ca for 15-20 min blocked the Cl-dependent but not the K-dependent component of giant IPSPs evoked by bath-applied 4-AP.(ABSTRACT TRUNCATED AT 400 WORDS)

Cerebral aneurysms: assessment of 377 cases (1956-1982)

A review of 177 patients with cerebral aneurysms is made, out of whom 106 with ruptured aneurysms were examined, whose operational timing and prognostic chances were well documented (group B, 1979-1982) and in part updated to 1984. Furthermore, relevant data of a previous series of 200 cases of cerebral aneurysm, treated between 1956-1978 were used (group A). The patients were graded according to Hunt and Hess, assessing the risks involved. The percentages of recurrent bleeding were in group A 36.5% and 28% in group B. The incidence of vasospasm (as seen in angiography) was in group B 39.6% (42/106 patients). The highest rate of vasospasm in the spasm group division B was found to occur in the second and third week after subarachnoid haemorrhage and amounted to 64.7% and 62.5%. A pre-operatively present vasospasm had no negative effects on the mortality rate, but influenced the outcome for the survivors effectively. The total mortality in group A was 22.5% and in group B 11.7%. Timing of the operation among patients in Hunt and Hess-grades I and II needs to discussion. The surgical position of patients in grade V is also certain. What remains to be discussed and needs attention is grade III and patients in grade IVa. Here the time of operative intervention must be planned individually depending on the course of the neurological status.