Specific disengagement of cell-bound anti-LAM-1 (anti-L-selectin) antibodies by aurintricarboxylic acid

Brief treatment of human peripheral blood lymphocytes with the potential anti-HIV compound aurintricarboxylic acid (ATA) prompts the selective release of already bound L-selectin-specific anti-Leu8 and anti-LAM1-1 antibodies from the cells. Two other anti-LAM1 antibodies, anti-LAM1-3 and anti-LAM1-5 stay antigen-bound at the same time. Interestingly, the ATA-sensitive anti-Leu8 strongly competes with the ATA-resistant anti-LAM1-3 for binding. Photobleaching fluorescence resonance energy transfer (pFRET) measurements on flow-sorted cells suggests that these two antibodies compete for the same epitope, while anti-LAM1-5-FITC and anti-Leu8-PE bind to distinct sites, although they also compete for binding. Combining the data on competition, pFRET and ATA effect, we suggest that the ATA sensitive anti-Leu8 and resistant anti-LAM1-3 bind to overlapping but non-identical epitopes. This remarkably specific effect may be exploited for designing anti-inflammatory drugs that modulate leukocyte adhesion.

Binding of the AMPA receptor antagonist [3H]GYKI 53405 to Xenopus brain membranes

GYKI 52466 and related 2,3-benzodiazepines are highly selective antagonists of AMPA-evoked responses in rat CNS. However, these compounds do not compete with [3H]AMPA binding and their site of action remains unclear. Here we show that [3H]GYKI 53405 binds specifically to Xenopus brain membranes with KD and Bmax values of 4.5 microM and 35 pmol mg-1 protein respectively. Binding is increased in the presence of Mg2+ and is unaffected by AMPA or kainate. This is the first report of the binding of a GYKI 52466-related radioligand to any tissue and these results provide an initial step towards the characterization of novel recognition sites which are of considerable therapeutic potential.

[Relation of the histological picture of biopsy material and prognosis in cases of squamous cell carcinoma of the oral cavity]

Biopsy specimens from 42 oral cancer cases were graded by a histological scoring system which was initiated by Bryne et al. This system was based on both the features of the tumor cells and the relationship between tumor cells and connective tissue. The results suggested significant correlation between the histological score values and the survival, the occurrence of recidive tumors and metastatic tumors.

Mutations in the protein phosphatase 1 gene at 87B can differentially affect suppression of position-effect variegation and mitosis in Drosophila melanogaster

The suppressor of position effect variegation (PEV) locus Su-var(3)6 maps to 87B5-10. The breakpoints of deficiencies that define this interval have been placed on a 250-kb molecular map of the region. The locus is allelic to the ck19 complementation group previously shown to encode a type 1 serine-threonine protein phosphatase (PP1) catalytic subunit. When introduced into flies by P element-mediated transformation, a 5.8-kb genomic fragment carrying this gene overcomes the suppressor phenotype of Su-var(3)6(01) and recessive lethality of all mutations of the locus. Four of the mutant alleles at the locus show a broad correlation between high levels of suppression of PEV, a high frequency of aberrant mitosis and low PP1 activity in larval extracts. However, some alleles with low PP1 activity show weak suppression of PEV with a high frequency of abnormal mitosis, whereas others show strong suppression of PEV with normal mitosis. The basis for these discussed.

[Correlation between tumor regression and survival time after chemotherapy in cancer of the oral cavity]

The examinations were performed on thirty patients with biopsy-confirmed squamous cell carcinoma of the oral cavity in clinical stage T2-3No-2M0. The aim of the present study was to perform a histological evaluation of the effect of preoperative intra-arterial treatment of surgically removed tumours and to analyse the correlations with the survival of the patients. The tumour regression (R) was evaluated quantitatively on a scale ranging between 1 and 4 points. The evaluation yielded a value of R1 in 8/30 cases (residual tumour was not found histologically). A tumour of microscopic size (R2) was found in 5/30 cases. Partial regression (R3) was established in 12/30 cases, and a slight response (R4) in 5/30 patients. The histologic picture was evaluated qualitatively on the basis of three arbitrarily chosen parameters. Examinations were made on the morphological picture of the residual cancer (C), the inflammatory reaction of the stroma (S) and the demarcation tendency of the tumour (D) and the sum of these values (A). The higher this point score, the poorer the tumour in question responds. Tumours with a score of A3-5 proved to have a very favourable prognosis in contrast with those with a score of A8-9. For the borderline scores of A6-7 the subsequent fate of the patient was decided by the extent of the original tumour and by the occurrence or not metastases. It is noteworthy that, with a comparatively small number of patients, a significant correlation was demonstrated between the survival and the total qualitative point count (A), the S value and the D value.

Waldenström's macroglobulinaemia presenting with cold urticaria and cold purpura

A case of Waldenström's macroglobulinaemia presenting with non-specific dermatological symptoms (cold urticaria and cold purpura) is described in a 37-year-old female patient. Progressive telangiectasia and spider naevi were also observed. Involvement of the skin may be explained by the presence of macroglobulins with cryoprotein-like qualities. This facilitated an early diagnosis.

Femtosecond gain characteristics of the discharge-pumped ArF excimer amplifier

The gain characteristics of a discharge-pumped ArF excimer amplifier are measured with ~700-fs-long pulses. The small-signal gain and saturation energy are found to be 0.17 cm(-1) and 3.65 +/- 0.15 mJ/cm(2), respectively. The maximum output energy density extracted from the deeply saturated amplifier is as much as 10 mJ/cm(2). The demonstrated femtosecond gain characteristics of ArF indicate that, by utilizing sufficiently high seed pulse energies, the ArF excimer laser is expected to show a performance similar to a femtosecond high-brightness KrF excimer laser system.

Plume emission, shock wave and surface wave formation during excimer laser ablation of the cornea

Excimer lasers are now used for corneal surgery; however, the physical processes occurring during photoablation of the cornea are incompletely understood. High speed laser-based photographic arrangement was constructed. The temporal resolution was better than 1 ns. The setup could work as a Schlieren arrangement, which is sensitive to the refractive index change caused by the shock wave propagating in the air above the eye. With minor changes the setup was converted into a shadowgraph, which could detect the ablation plume and the waves propagating on the surface of the eye. Due to the impact of the excimer laser pulse onto the surface of the cornea, a shock wave was generated in the air. The shadowgraph clearly showed the ejection of the ablated cornea. The ejection velocity of the plume was found to be over 600 m/s. It was shown for the first time that the recoil forces of the plume are generating a wave on the surface of the eye. The laser-based high speed photographic arrangement is a powerful arrangement in the study of physical effects occurring during photoablation of the cornea.

[Closure of cleft palate in adult patients, using a forearm flap with microvascular radial artery II]

A clinical report on the utilization of the so called "Chinese Flap" first published in 1981 is presented by the authors. The basic principle of this method is the following: After closing the soft palate in three layers, a mucoperiosteal flap has been prepared from the palatal mucosa and rotated into the nasal cavity so to close nasally the defect in one layer. Than a pediculated fasciocutaneous flap containing both the radial artery and the two comitantes veins prepared from the forearm was sutured to the defect. The a radialis and the v. comitantes running forward and downward between the two layers of the soft palate passing the mandibular ramus and descending through a tunnel leading to the submandibular region were joined to the facial artery and veins and an anastomosis was established. The clinical experience with the "Chinese Flap" procedure showed good results. This method has been used in 12 cases so far and only one out of the 12 failed due to blood vessel developmental abnormalities.

[Favorable in vitro effect of pentoxifylline on damaged lymphocyte migration in arteriosclerosis obliterans and systemic lupus erythematosus]

Decreased blood cell--e.g. lymphocyte--motility is seen in a number of vascular and autoimmune diseases. Pentoxifylline (Pf) shows a well-known therapeutic effect in several vascular alterations by causing the redistribution of blood cell cytoskeleton and increased microcirculation. As most literary data on Pf concern red blood cells and granulocytes authors here investigated the effect of Pf on previously decreased lymphocyte migration and chemotaxis. Results of in vitro studies suggest that Pf enhances impaired lymphocyte motility in obliterative arteriosclerosis and systemic lupus erythematosus and thus may also be introduced in the treatment of polysystemic autoimmune diseases.

[Lasers in otologic surgery]

The author makes known the possible advantages of the laser-application in the ear surgery. He informs about the main tissue effects of the surgical lasers used in practice. On the bases of the bibliography and his own experiences the author offers a survey of the indications of laser-oto-surgery.

Mechanical properties of bone after grafting with coralline hydroxyapatite: an experimental study

Based on animal experiments, mechanical properties of rabbit radii after grafting artificial gaps with a coralline hydroxyapatite (CH) material are discussed. Healing velocity of complete and partial gaps after the same kind of grafting is also analyzed. Based on the results obtained from 48 gaps of 24 animals it is stated that fused grafts in both types of gaps showed bending strength of the radii similar to that of normal bone. The incidence of nonunions and infections are also discussed. It is concluded that CH is suitable in the treatment of incomplete bone defects.

Role of endogenous corticotropin-releasing factor in mediation of neuroendocrine and behavioral responses to cholecystokinin octapeptide sulfate ester in rats

The possible involvement of endogenous corticotropin-releasing factor (CRF) in the anxiogenic and pituitary-adrenal-axis-activating effects of cholecystokinin octapeptide sulfate ester (CCK 8) was investigated in rats. Intracerebroventricularly (i.c.v.) administered CCK 8 induced an anxiogenic response in an elevated plus-maze test, and enhanced the plasma corticosterone level. Pretreatment with different dilutions (1:10, 1:20 and 1:100, i.c.v.) of CRF antiserum and different doses of a CRF receptor antagonist, alpha-helical CRF (ahCRF, 0.001-1.0 microgram, i.c.v.) prevented the anxiogenic response to CCK 8 in a dose-dependent manner. None of the doses of CRF antiserum or ahCRF alone produced any alteration in either the elevated plus-maze paradigm or corticosterone level in saline-treated control rats. The results strongly suggest that the anxiogenic and hypothalamo-pituitary-adrenal-activating effects of CCK 8 are mediated via CRF.

Spectrally compensated sum-frequency mixing scheme for generation of broadband radiation at 193 nm

A dispersively compensated scheme for sum-frequency mixing of broadband ultrashort laser pulses is reported. An increase of the bandwidth of the sum-frequency mixing process by 12 times compared with the noncompensated bandwidth of the given crystal has been demonstrated. Mixing radiation at 266 and 707 nm in a 1-mm-thick beta-barium metaborate crystal by using the compensated scheme results in an output bandwidth of 0.6 nm at 193 nm, which corresponds to a minimum output pulse duration of 90 fs.

Opposite actions of oxytocin and vasopressin in the development of cocaine-induced behavioral sensitization in mice

Subchronic administration of cocaine induces behavioral sensitization (increasing hypermotility) to a challenge dose of the drug administered 72 h after the cessation of treatment. The effects of repeated administration of the neurohypophyseal hormones oxytocin (OXT) and arginine8-vasopressin (AVP) on the development of behavioral sensitization induced by subchronic treatment with cocaine were investigated in mice. Repeated treatment of OXT and AVP did not modify the locomotor stimulatory effect of the challenge dose of cocaine in cocaine-naive control animals. OXT in a dose of 0.5 microgram (sc) augmented the cocaine-induced behavioral sensitization. In contrast, AVP (0.005-0.5 microgram/mouse, sc) dose dependently attenuated the development of sensitization to the hypermotility-inducing effect of cocaine. The results suggest that the behavioral sensitization induced by cocaine can be modulated in opposite directions by neurohypophyseal hormones.

Oxytocin blocks the development of heroin-enkephalin cross-tolerance in mice

The development of cross-tolerance to an analgesic effect has been observed between a mu-receptor agonist, heroin, and a delta-receptor agonist, Met2-Pro5-enkephalinamide. Repeated treatments with heroin twice a day for 4 days resulted in a decreased nociceptive effect to enkephalin on day 5. The enkephalin dose-response line was shifted to the right, considered a sign of the development of cross-tolerance. Peripheral treatment with oxytocin blocked the development of heroin-enkephalin cross-tolerance. A similar effect was observed after intracerebroventricular administration of oxytocin, supporting our assumption that oxytocin blocks the development of heroin-enkephalin cross-tolerance via CNS mechanisms.

Effects of atrial natriuretic peptide on acute and chronic effects of morphine

Atrial natriuretic peptide (ANP) is known to participate in different vegetative functions. The aim of the present study was to investigate the influence of ANP on nociception itself, pain sensitivity to morphine, and the development of acute and chronic tolerance to morphine. Morphine withdrawal signs were also evaluated by injecting naloxone. In adult, male NMRI mice, ANP administered SC or ICV did not affect pain sensitivity itself in a heat-radiant tail-flick test. Peptide treatment, however, depressed the acute nociceptive effect of a single dose of morphine (4 mg/kg, SC) after both SC (20-200 ng/animal) and ICV (5, 10, 20, or 200 ng/animal) ANP administration. ANP given SC and ICV attenuated the development of acute morphine tolerance. Acute morphine tolerance was assessed by giving a bolus injection of morphine (60 mg/kg) 24 h before the pain sensitivity to a challenge dose of morphine (4 mg/kg) was measured. ICV treatment with ANP also blocked the development of chronic morphine tolerance, but did not affect the appearance of naloxone-precipitated withdrawal syndromes. ANP seems to act differently on the development of tolerance to and dependence upon morphine.