Hydrogen storage properties of MgH2-diatomite composites obtained by high-energy ball milling.

To investigate the effects of specific porous microstructure of diatomite on the hydrogen storage properties of MgH(2), a two-step preparation was carried out. The first step was decrepitation of MgH(2) particle size during 10 h of milling. The second step was additional 1 h of milling with diatomite. The microstructure and phase composition of materials was characterized by X-ray diffraction, whereas the powder morphology and degree of additive dispersion were analyzed by scanning electron microscopy. The hydrogen desorption behaviour of nanocomposites was investigated by differential scanning calorimetry. The results show that addition of porous diatomite structure leads to decrease in desorption temperature, since there was no other effect that can have an influence on kinetics, such as formation of the metastable gamma-phase, reduction of oxides to the native metal and/or homogeneous dispersion of the catalyst. This indicates that the microstructure of added material plays the main role in the enhancement of desorption properties of composites.

[Chronic venous insufficiency and compression therapy]. / Hronicna venska insuficijencija i kompresivna terapija.

INTRODUCTION: Disorders of venous circulation are among most frequent diseases in the human population. During recent years there has been increased interest in physiopathology of chronic venous insufficiency (CVI), due to development of more accurate diagnostic methods and new therapeutic techniques. Considering patophysiology of CVI and its consequences the crucial points are stasis and reflux of blood flow, with increase of intravascular pressure. CLASSIFICATION AND THERAPY OF CVI: Empirical experience and theoretical models suggest that progression of the disease can be stopped or reverted by correction of stasis. Today, this is the main direction in all therapeutic approaches. Compression therapy represents the most successful conservative technique. In this article we are presenting basic principles of the compression therapy of CVI. Evidence for the physiologic effect of compression therapy are decrease of edema, softening of lipodermatosclerosis, acceleration of venous flow, decrease in venous volume, blood shift into central compartments, reduction of venous refluxes, influence on arterial flow and improvement of microcirculation and lymph drainage. There are several types of compression devices: elastic stockings, elastic bandages, inelastic bandages, intermittent pneumatic compression devices. Other advantages of compression therapy are decrease of hospital treatment and better quality of life for patients with CVI.

[Characteristics of the Koebner phenomenon in patients with psoriasis vulgaris]. / Neke karakteristike Koebnerovog fenomena u obolelih od vulgarne psorijaze.

INTRODUCTION: Koebner phenomenon in psoriasis presents development of psoriatic lesions, after injury of uninvolved skin, which are identical in morphology with the previous trauma. The aim of this study was to establish the correlation of Koebner phenomenon with sex and age distribution, clinical variants of psoriasis vulgaris, age of onset and incidence in psoriasis among relatives of affected patients. MATERIAL AND METHODS: Sixty patients, with severe clinical picture, participated in this study: 38 patients in acute flare of a chronic form; 10 with acute exanthematic form; 8 with a chronic stable form; 3 with psoriatic changes on palms and soles and one patient with psoriatic erythroderma. According to the presence of Koebner phenomenon they were divided in two groups, one with positive and the other with negative Koebner phenomenon which presented the control group at the same time. RESULTS AND DISCUSSION: The Koebner reaction is often thought to be more frequent in actively spreading, severe psoriasis. Although this may be true, it has to be established by prospective studies. According to our investigation, Koebner phenomenon did not depend on clinical picture of psoriasis vulgaris. This reaction also appears to be a marker for a subgroup of patients with a tendency to early onset, but that was not confirmed by our study. In available literature we did not find any data about relations of Koebner phenomenon to sex and age or familiar incidence of psoriasis vulgaris. Our results demonstrated no connection of Koebner phenomenon with sex and age structure. At the same time its presence did not depend on familiar incidence of psoriasis vulgaris. CONCLUSIONS: There is no relationship between Koebner phenomenon and sex and age distribution. It does not depend on clinical picture and also does not predict the age of onset and familiar incidence of psoriasis vulgaris.

[The Koebner phenomenon, a prognostic sign of PUVA therapy effectiveness in patients with psoriasis vulgaris--yes or no?]. / Koebnerov fenomen, prognosticki znak efikasnosti PUVA terapije u bolesnika sa vulgarnom psorijazom--da ili ne?

INTRODUCTION: Former investigations of Koebner phenomenon had demonstrated its higher incidence in patients with severe generalized and/or unstable forms of psoriasis which expressed increased resistance to various treatment modalities. The aim of this study was to establish the correlation between the presence of Koebner phenomenon and the PUVA therapy effects, total number of PUVA treatments, total dose of UVA radiation and the duration of remission after PUVA therapy discontinuation. MATERIAL AND METHODS: Sixty patients with severe clinical picture of psoriasis vulgaris, treated with PUVA therapy, were included in this research. According to the presence of Koebner phenomenon they were divided into two groups, 20 patients with positive and 40 patients with negative Koebner reaction, who were the control group at the same time. RESULTS AND DISCUSSION: 95% of patients treated with PUVA, were cleared of psoriatic changes in the Koebner positive, as well as in the Koebner negative group. There were also no differences between the Koebner positive and Koebner negative group in the mean number of PUVA treatments, mean total dose and the last dose of UVA radiation, which led up to the clinical remission of psoriasis. Our results of investigation have demonstrated increased relapse of psoriasis, during the first 6 months after cessation of PUVA therapy, in the Koebner positive group, with a high statistical significance (p < 0.001), comparing with Koebner negative group in the same period. Furthermore, the tendency of relapse of Koebner positive and Koebner negative psoriatic patients was higher in Koebner positive group even in the first 3 months after PUVA therapy. CONCLUSIONS: PUVA therapy effects, total number of PUVA treatments, total dose of UVA radiation didn't depend on presence of Koebner phenomenon. However, Koebner phenomenon was a mark of high relapsing tendency of psoriasis in the first 6 months after PUVA therapy cessation.

[Epidemiologic characteristics of viral dermatoses--results of a retrospective study]. / Neke epidemioloske odlike virusnih dermatoza--rezultati retrospektivnog ispitivanja.

INTRODUCTION: A great number of skin diseases are caused by viruses (1, 2, 3). Virus infections can cause skin diseases due to three mechanisms: direct inoculation, systemic infection and local spreading of the internal focus. The aim of this study was to determine the characteristics of virus-associated dermatoses (VD). MATERIAL AND METHODS: Ambulant patients of policlinical department of the Clinic of Infectious and Dermatovenereological Diseases Novi Sad were included in this study. Epidemiologic characteristics were analyzed by retrospective studying of medical documentation. RESULTS: During a five-year-period (1991-1995), 1,461 cases of VD were registered or 7.09% of the total number of patients examinated in this period (N = 20.596). Majority of the observed patients were males (N = 788-53.25%) and female patients were less frequent (N = 683-46.75%, table 1). Table 2 shows the age distribution of our patients. Most of the patients were in the 20-29 year age group (N = 443 or 30.32%). The mean age of patients was X = 36.14 years (SD = 19.02). Table 3 shows the occupational structure of our patients. The most frequent was the group of employed (N = 773 or 50.17%). Table 4 shows the structure of the patients according to pathogenic agents. The most frequent was the group of warts and condylomata (N = 900 or 61.60%). It is apparent that the number of VD is increasing. DISCUSSION: According to collected data, patients with VD make up a great group being treated at dermatological clinics. Our findings (7.09%) are compatible to the standard results. A relative high mean age of our patients is determinated by the fact that the children are managed at the Institute of Health Care of Mother and Child Novi Sad (the warts are most frequent in this population) or in other dermatological ambulants. There is no evidence that actual socio-political events affect the spreading of VD. Most patients belong to the urban population making up dominant groups (employed, scholars, pensioners). CONCLUSION: The number of patients with VD is increasing. Although from year to year the number of diseased increases or decreases, generally speaking there is an increasing trend of VD.

[Modern psychosomatic aspects of dermatology]. / Savremeni psihosomatski aspekti u dermatologiji.

Concerning their origin most diseases are multifactorial and that goes for skin diseases too. Emphasizing just one must not exclude further research and other aspects of etiopathogenetic mechanisms. It has been known for along time that psychological factors have a certain influence on the start, aggravation and maintenance on skin changes and that cosmetic defects of this kind disturb the psychological peace of the sick person and his capacity of establishing satisfactory social relations. Psychosomatic approach in dermatology cannot be reduced to investigation of specific etiology in the field of psyche without physical or social spheres. It unites all of them and in that way the old question what cause and what the consequence is has no importance, because there is no time or distance limit among them. They act simultaneously, holistically.

[Phagocytic activity of polymorphonuclear cells in patients with psoriasis vulgaris from the aspect of PUVA therapy]. / Fagocitna aktivnost polimorfonukleara u bolesnika s vulgarnom psorijazom s aspekta primenjene PUVA terapije.

The authors present results of examining phagocytotic activity of polymorphonuclear (PMN) granulocytes in patients with psoriasis vulgaris from the aspect of applied PUVA-therapy. 100 patients with psoriasis vulgaris were examined and divided into three groups, 20 patients with acute exanthematous form of the disease, 16 patients with chronic stationary form of the disease, and 64 patients with acute phase of the chronic form of the disease. 50 healthy persons made up the control group. Phagocytotic activity of neutrophils was examined by opsonization test, a modified method by Brandt. Phagocytotic index was expressed as a number of ingested particles of yeast germs in 100 PMN. Polymorphonuclears of patients were examined in the autologous and control serum of healthy people. Values of immunoglobulin IgM and IgG as well as values of complement C3 were examined in all patients using the method of laser nephelometry (Behring). All mentioned parameters were determined prior to and after PUVA therapy which was conducted by apparatus: PUVA 4000 and 6001. Results of examination show that the phagocytotic activity of PMN in patients with psoriasis vulgaris is normal and that it does not depend on how skin disorders are spread, on the strength of infiltration, exudation, the length of duration and course of the disease, as well as on applied PUVA-therapy. Reduced phagocytotic activity of PMN was determined only in individual cases, that is in 5 patients not depending on the applied therapy. In one patient hypoimmunoglobulinemia IgM as a probable cause of disturbed phagocytosis was established while in the remaining 4 patients causes of reduced phagocytosis remained unknown.