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The research revealed crystallographic structure of the gingival fluid in healthy teeth and by inflammatory periodontal disease. Comparing the results with clinical data both crystallographic patterns in healthy teeth gingival fluid and markers of periodontal tissue pathology were established.

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We have assessed parameters of myocardial electrical instability in patients with postinfarction atherosclerosis before and in one year after coronary bypass surgery. Inclusion criteria were history of myocardial infarction, surgical myocardial revascularization between 1 and 2 years before; stable course of coronary heart disease during previous month; preserved ejection fraction ( more or equal 50%), stable sinus rhythm. Heterogeneity of myocardial electrophysiological properties has diminished after coronary bypass surgery due to improvement of coronary perfusion and restoration of function of ischemic myocardium. This have been associated with positive dynamics of interval QT dispersion, parameters of turbulence and variability of cardiac rhythm, reduction of the rate of registration of ventricular late potentials.

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The authors revealed dependence of reaction blood plates to photoeffect on the dose and rate of blood movement at laser radiation of donor blood in vitro. The red light decreases adhesion and aggregation of blood plates both at high and low rate of shift. Infrared laser radiation is effective only at high rate of shift leading to increase of adhesion and decrease of aggregation of blood plates. Blue laser is effective in small doses only and at low rate of sift it leads to decrease of adhesion and at high rate it provokes increase of adhesion. Blue laser do not have a significant influence on aggregation of blood plates. These results make possible to suppose ambiguity of biological response of venous and arterial blood to radiation.

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Most of the space demands in the cerebellopontine angle lie extra-axially. Important structures run within the cisterns of the cerebellopontine angle, such as the trigeminal, facial and vestibulocochlear nerves as well as the anterior inferior and posterior inferior cerebellar arteries and the veins which lead to the petrosal sinus. The most common space demands are caused by acoustic neuromas, meningeomas, vascular ectasia and aneurysms. Less common are epidermoid and other schwannomas as well as metastases, paragangliomas and arachnoidal cysts. Intra-axial tumours in the area of the cerebellopontine angle include the medulloblastoma, astrocytoma and the ependymoma, which occurs predominantly in children, in addition to the uncommon choroid plexus papilloma. Nearby, there are also space demands around the petrous bone, such as cholesterol granuloma, malignant otitis media, paraganglioma and metastases. For differential diagnosis, an understanding of the space requirements of the tumours in the cerebellopontine angle is needed in addition to knowledge of the anatomical structures.

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BACKGROUND: Among the chemokines related to CXC and CC receptor groups and released from platelets, leukocytes and endothelial cells, SDF-1, TARC and MDC have been found to be platelet agonists. Platelets do not contain SDF-1 alpha. In contrast, RANTES is constitutively present in platelet alpha-granules and released upon platelet activation. OBJECTIVES: To study a possible role of RANTES as a modulator of SDF-1 alpha effect on platelets, in relation to CXCR4 and various CC receptors. METHODS: CXCR-4 (CXCL12) receptor expression and platelet activation were evaluated by flow cytometry, platelet deposition was studied by cone and plate(let) analyzer, and platelet aggregation by turbidometric aggregometry. RESULTS: Flow cytometry studies revealed similar expression of CXCR-4, the specific receptor of SDF-1 alpha on intact, inactivated, and activated platelets. Preincubation of platelets with RANTES affected neither CXCR-4 expression, nor SDF-1 alpha binding to the platelet membrane. In the presence of fibrinogen, SDF-1 alpha activated gel-filtered platelets. RANTES did not activate platelets, but substantially (by 70%) inhibited SDF-1 alpha-induced fibrinogen binding. Similarly, RANTES abrogated the promoting effect of SDF-1 alpha on whole blood platelet adhesion to endothelial cell monolayer under venous flow conditions. In platelet-rich plasma, RANTES moderately inhibited SDF-1 alpha-induced platelet aggregation, while it did not affect aggregation induced by thrombin-receptor activation peptide, adenosine diphosphate, or phorbol 12-myristate 13-acetate. A synergistic inhibitory effect of RANTES and prostaglandin E1 used at subthreshold concentrations, on SDF-1 alpha-induced aggregation and SDF-1 alpha-induced fibrinogen binding to platelets was observed, which may suggest involvement of RANTES in a cAMP-dependent signal transduction pathway. CONCLUSIONS: RANTES non-competitively inhibits activation of platelets by SDF-1 alpha, and thus may play a regulatory role in platelet response to inflammation.

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In August 1908 Karl August Bier, Professor of Surgery in Berlin, described a new method of producing analgesia of a limb which he named 'vein anesthesia'. Bier first presented his new method of intravenous regional anesthesia (IVRA) at the 37th Congress of the German Surgical Society on 22 April, 1908, only 10 years after his significant communication on spinal anesthesia (1). His method, which now bears his name, consisted of occluding the circulation in a segment of the arm with two tourniquets and then injecting a dilute local anesthetic through a venous cut-down in the isolated segment. Bier had the good fortune to use procaine, the first safe injectable local anesthetic that had been synthesized by Einhorn in 1904.

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Topical application of sodium nitroprusside on rat mesentery has a marked influence on lymph microvessels function. The drug causes a dilation of majority of lymphangions and decrease of the pacemaker activity of the vessel wall structures and valves. These changes do not lead to lymph stasis, and lymph flow velocity does not reduce. The non-selective inhibitor of NO synthase (N-nitro-L-arginine) intensifies vasomotions of lymph microvessels, modulates phasic contractile activity and increases lymph flow velocity. There is a time dependent dynamic of changes in action of N-nitro-L-arginine. During inhibition of endogenous NO synthesis the responses of lymph microvessels on sodium nitroprusside application are modified: the constriction of majority lymphangions and activation of valve work are observed.

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Stress caused by immobilization and acoustic stimulation produces considerable changes in lymph microcirculation. These changes manifested in dilation of microvessels, enhanced phasic contractile activity and its abnormal pattern, accelerated lymph flow, and recruitment of new lymphangions in drainage functions.

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Lymph flow as measured with biomicroscopic and speckle-interferometrical techniques was very unstable and its rate did not depend on lymphangion diameter in the rat mesentery. A correlation was found between amount of cells in the lymph flow and other indices of lymphangion functions. All microvessels with phasic contractions and/or working valve were revealed as having a lymph flow. The phasic activity and the valve work correlated with each other. The higher the amplitude and frequency of the phasic activity and the longer the contraction cycle, the higher was the rate of the valve work.

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Global regulatory genes in Staphylococcus aureus, including agr and sar, are known to regulate the expression of multiple virulence factors, including cell wall adhesins. In the present study, the adherence of S. aureus RN6390 (wild type), RN6911 (agr), ALC136 (sar), and ALC135 (agr sar) to immobilized fibrinogen, fibronectin, von Willebrand factor (vWF), extracellular matrix (ECM), and human endothelial cells (EC) EAhy.926 was studied. Bacteria grown to postexponential phase were subjected to light oscillation (static condition) or to shear stress at 200 s(-1) (flow condition) on tissue culture polystyrene plates coated with either protein ligands, ECM, or EC. Adherence of nonlabeled bacteria to immobilized ligands was measured by an image analysis system, while adherence of [(3)H]thymidine-labeled S. aureus to ECM and EC was measured by a beta-scintillation counter. The results showed increased adherence of agr and agr sar mutants to immobilized fibrinogen and higher potential of these mutants to induce platelet aggregation in suspension, decreased adherence of sar and agr sar mutants to immobilized fibronectin and vWF as well as to ECM and EC, increased adherence of both S. aureus wild type and sar mutant to EC treated with platelet-rich plasma (PRP) compared to platelet-poor plasma (PPP) and to EC treated with PPP compared to the control, and increased adherence of S. aureus wild type to EC coated with PRP in which platelets were activated with phorbol 12-myristate 13-acetate compared to intact PRP. This finding paralleled the increased adherence to EC of activated compared to intact platelets. It is suggested that platelet-mediated S. aureus adherence to EC depends on platelet activation and the number of adherent platelets and available receptors on the platelet membrane. In conclusion, the agr locus downregulates S. aureus adherence to fibrinogen, while the sar locus upregulates S. aureus adherence to fibronectin, vWF, ECM, and EC. The effect of both agr and sar on S. aureus adherence properties develops primarily under flow conditions, which suggests different adhesion mechanisms in static and flow conditions.

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Lumbar epiduro-arachnoiditis is an infectious disease of the three mengial layers. It is often caused by surgical interventions on the spine. In this survey etiologic factors, clinical symptoms and radiological findings are compared. The radiologic classification of Delamater is described by three clinical cases. The diagnostic value of different procedures such as myelography, postmyelographic computed tomography and MR imaging is evaluated.

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The VersaMed 201 is a lightweight, computer-controlled, electrically driven ventilator, designed for transport, home-ventilation and field use. We have evaluated the device in human beings with healthy and pathological lungs. In the first part of the study, the VersaMed was substituted for a standard operating room ventilator for 15-30 min during elective surgery in 20 subjects. In the second stage of the study, 20 patients with lung pathology who were being ventilated in the critical care department were transferred to the VersaMed for a 30-min period. In all the patients studied, arterial blood gases, haemodynamic parameters and other respiratory variables were maintained at similar values seen with the standard ventilators used. We conclude that the VersaMed 201 is suitable for use in human beings with healthy and pathological lungs as a reliable, portable ventilator.

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The effect of He-Ne laser irradiation on platelet adhesion, activation and aggregation was investigated. Citrated whole blood was irradiated in vitro by He-Ne laser (632.8 nm, 7 mW) and then subjected to shear stress (1300 s-1) on subendothelial extracellular matrix (ECM)-coated plates. Laser irradiation was followed by a decrease in platelet adhesion and aggregation on ECM under flow conditions in a time exposure-dependent manner (by 30-40%). The inhibiting effect of laser light on platelets was detectable up to 1 h after the termination of irradiation. Laser irradiation of either platelet-rich plasma, gel-filtered platelets, platelet-poor plasma, or packed blood cells followed by whole blood reconstitution revealed a marked decrease in platelet deposition on ECM only in the cases of platelet-rich plasma or gel filtered platelets. In conventional aggregometry, laser-treated platelet-rich plasma demonstrated a diminished platelet response to both thrombin receptor-activating peptide (TRAP), converting a two-wave aggregation curve to reversible, and to the protein kinase C activator PMA (by 45%). In flow cytometry analysis, irradiated platelets presented lower fibrinogen binding and P-selectin expression in response to TRAP. Laser irradiation had no additional inhibitory effect on dibutyryl cGMP- and dibutyryl cAMP-pretreated platelets. A 50% increase in cGMP level was observed in laser-treated gel filtered platelets, both in the presence and in absence of the phosphodiesterase inhibitor, isobuthylmethylxanthine. The results suggest that guanylate cyclase is one of the primary mediators of the laser effect on platelet function.

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The effect of dimethyl sulfoxide (dimexid, DMSO) on the lymph microvessels of the rat mesentery was studied by vital biomicroscopy. It was found that 30% DMSO increases the tonus of intact lymph microvessels and stimulates their phase contractions. Action of the agent for more than 15 min leads to the development of lymphostasis. DMSO has a pronounced corrective effect on disorders of lymph microcirculation caused by the staphylococcal toxin. It removes the main lymphopathogenic effects of the poison and normalizes the drainage function of the lymphangions. The correcting effect of DMSO on lymph circulation is attended with attenuation of the fatal effect of the toxin.

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