Cryosurgery of lentigo maligna.

Lentigo maligna denotes flat, pigmented lesions predominantly in areas of actinic damage that have the propensity to become malignant. More than 10 years may pass before lentigo maligna evolves into an invasive neoplasma. As an invasive process, it is termed lentigo maligna melanoma (LMM), and it has the potential for both lymphatic and hematogenic metastases. Because of the size and location of the lesions, cosmetically unsatisfactory scars may result from conventional surgery. Therefore, alternative means of treatment, including cryosurgery, have been employed. We report on 12 patients suffering from lentigo maligna who had been treated successfully by cryosurgery between 1984 and 1990. The average follow-up period was 51.4 months, and the recurrence rate was 8.3 percent. Knowing that microinvasive components can be demonstrated in 15 percent of lentigo maligna lesions, we retrospectively reassessed our patients by immunohistochemical procedures with S-100 protein. Although intradermal microinvasion could be confirmed in one patient, no recurrence had been observed within 61 months of follow-up. Provided that patients are selected properly and extension of cryonecrosis is monitored, cryosurgery may prove an efficient alternative to conventional surgery in the treatment of lentigo maligna.     

Metastable ripple phase of fully hydrated dipalmitoylphosphatidylcholine as studied by small angle x-ray scattering

Fully hydrated dipalmitoylphosphatidylcholine (DPPC) undergoes liquid crystalline to metastable P_β, phase transition in cooling. A small angle x-ray scattering study has been performed for obtaining further evidence about the structure of this phase. From a high-resolution observation of x-ray diffraction profiles, a distinct multipeak pattern has become obvious. Among them the (01) reflection in the secondary ripple structure is identified clearly. There are peaks assigned straightforwardly to (10) and (20) reflections in the primary ripple structure and peaks assigned to (10) and (20) reflections in the secondary ripple structure. Therefore the multipeak pattern is due to superposition of the reflections cause by the primary and secondary ripple structures. The lattice parameters are estimated as follows: for the primary ripple structure a = 7.09 nm, b = 13.64 nm, and γ = 95°, and for the secondary ripple structure a = 8.2 nm, b = 26.6 nm, and γ = 90°. The lattice parameters thus obtained for the secondary ripple structure are not conclusive, however. The hydrocarbon chains in the primary ripple structure have been reported as being tilted against the bilayer plane and, on the other hand, the hydrocarbon chains in the secondary ripple structure are likely to be perpendicular to the bilayer plane. This fact seems to be related to a sequential mechanism of phase transitions. On heating from the L_β, phase where the hydrocarbon chains are tilted the primary ripple structure having tilted hydrocarbon chains takes place and on cooling from the L_α phase where the hydrocarbon chains are not tilted the secondary ripple structure with untilted chains tends to be stabilized. It appears that the truly metastable ripple phase is expressed by the second ripple structure although in the course of the actual cooling transition both the secondary and primary ripple structures form and coexist.     

Occurrence of Cladocera (Crustacea) in subterranean waters in Yugoslavia

Contrary to some localities in France and Spain, Cladocera occur in hypogean waters in Yugoslavia very sporadically. Beside the stygobitic species, Alona hercegovinae from caves and Alona smirnovi from interstitial waters, particularly some other Chydoridae seem to be suited for hypogean life. Chydorus sphaericus, reputed as one of the most euryoecious cladocerans, occurs also the deepest in interstitial waters as well as in caves. Other species, found in hypogean waters are Simocephalus vetulus, Ilyocryptus sordidus, Eurycercus lamellatus, Chydorus ovalis, Leydigia leydigi, Acroperus harpae and Biapertura affnis.     

Stimulation of dopamine synthesis and release by morphine and D-Ala2-D-Leu5-enkephalin in the mouse striatum in vivo

The effects of opiates on dopamine (DA) release and synthesis were assessed in the mouse striatum $\text{in vivo}$ by simultaneously measuring 3,4-dihydroxyphenylalanine (DOPA) and 3,4-dihydroxyphenylacetic acid (DOPAC) levels after inhibition of aromatic amino acid decarboxylase. This method was developed to assess stimulus-coupled changes in DA synthesis and release. Peripheral injections of morphine and intraventrcular injections of D-Ala²-Leu⁵-enkephalin elevated DOPAC levels, indicating that “opiates” stimulated DA release. Concomitantly, the rate of DA synthesis was increased. The effects were dose-dependent, saturable and antagonized by naloxone. When morphine and the enkephalin analog were given together in saturating doses, the effects of the two agents were not additive. Thus, the involvement of different receptors in the mediation of the effects of morphine and enkephalins could not be demonstrated.     

Effects of energy level and monensin on reproductive performance and lactation of beef cows

This experiment consisted of a 2 year drylot study involving 80 multiparous, suckled beef cows (40 Angus and 40 Herefords). Experimental treatments (breed, monensin and year) were arranged in 2(3) factorial to evaluate the effect of breed and monensin on reproductive performance and lactation. Cows received 85% of the NRC total digestible nutrient (TDN) requirement for the first 56 days of the 140 day trial. Cows were synchronized with Synchro-Mate B and artificially inseminated 30 days into each trial with blood samples collected for luteinizing hormone (LH) analysis from one-half of each treatment group from 24 to 36 hours after implant removal. Progesterone determinations were made on plasma samples collected at day 9 and 16 after implant removal. On day 56, milk yield estimates were obtained by the weigh-suckle-weight technique. Following these collections, energy levels were increased by allowing ad lib consumption of forage. Calves, which were removed from the cows during feeding, were given access to a 75% TDN creep ration after day 56. Milk estimates were again evaluated at 140 days. Monensin supplementation did not result in a difference in cow weight change through the restricted energy period (first 56 days) or throughout the entire 140 day period. Milk yield estimates at 56 and 140 days and calf gains throught the trial, were unaffected by monensin supplementation. Monensin resulted in no effect on conception rate or services per conception. The time of the LH peak was shifted slightly forward by monensin although not significantly. Progesterone levels were not consistently affected by monensin supplementation.     

A haemagglutination inhibition test kit for routine analysis of erythropoietin.

A commercially available haemagglutination inhibition test kit for routine analysis of erythropoietin was shown to be unable to detect elevated levels of serum Epo.