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D Pavlovic

Publications and source records attributed to D Pavlovic.

At least 19 recordsLinked to original sources
PubMed2006

Effects of glucocorticoids on polyamine metabolism in liver and spleen of guinea pig during sensitization.

Glucocorticoids are potent anti-inflammatory and immunosuppressive agents. As endogenous inhibitors of cytokine synthesis, glucocorticoids suppress immune activation and uncontrolled overproduction of cytokines, preventing tissue injury. Also, polyamine spermine is endogenous inhibitor of cytokine production (inhibiting IL-1, IL-6 and TNF synthesis). The idea of our work was to examine dexamethasone effects on the metabolism of polyamines, spermine, spermidine and putrescine and polyamine oxidase activity in liver and spleen during sensitization of guinea pigs. Sensitization was done by application of bovine serum albumin with addition of complete Freund's adjuvant. Our results indicate that polyamine amounts and polyamine oxidase activity increase during immunogenesis in liver and spleen. Dexamethasone application to sensitized and unsensitized guinea pigs causes depletion of polyamines in liver and spleen. Dexamethasone decreases polyamine oxidase activity in liver and spleen of sensitized guinea pigs, increasing at the same time PAO activity in tissues of unsensitized animals.

Animals↗
PubMed2006

[Transient ischemic attack due to Lambl's excrescence. Report of a case and review of the literature].

We describe a 42-year-old man presenting in the emergency department with transient ischemic attack without cardiovascular risk factors. Systemic disease and hypercoagulability substract was discarded. Only transesophageal echocardiography could confirm the presence of a Lambl's excrescence in the aortic valve (valvular strand). We review clinical management and new therapeutic options in stroke prevention used in this unusual source of cardiac embolism.

Aortic Valve↗
PubMed2006

Metronidazole improves intestinal microcirculation in septic rats independently of bacterial burden.

To explore the effects of metronidazole (Me) on intestinal microcirculation in septic rats, intravital microscopy (IVM) following 16 hours of colon ascendens stent peritonitis (CASP model) was used. Four groups of animals were studied: control group (sham operation) and CASP group, each with and without Me treatment (10 mg/kg i.v.). In order to investigate the substance-specific effects of Me independently of the antibacterial effects within a pathologically altered microcirculation, a second experimental series with lipopolysaccharide challenge (LPS model) was carried out. The LPS model consisted of the four groups (control animals and LPS animals (15 mg/kg i.v. LPS from E. coli) with and without Me). IVM in the LPS experiments was performed following a two hour observation period. Me treated CASP or LPS animals, as compared with untreated, demonstrated significant improvement of functional capillary density (FCD) of the intestinal wall. The increase in the number of leukocytes firmly adhered to the endothelium (leukocyte sticking) in the untreated CASP or LPS animals within the V1 venules of the intestinal submucosal layer, was significantly reduced in the Me treated animals. In conclusion, Me exerts beneficial anti-bacterial and anti-inflammatory effects within the septic microcirculation.

Animals↗
PubMed2005

Auricular acupuncture for pain relief after total hip arthroplasty - a randomized controlled study.

Auricular acupuncture (AA) is known to be effective in treatment of various pain conditions, but still there have been no randomized controlled studies of AA for treatment of acute postoperative pain. Therefore we tested whether AA of specific points is superior to sham acupuncture for complementary analgesia after total hip arthroplasty in a patient-anesthesiologist-evaluator-analyst blinded study. The patients were randomly allocated to receive true AA (lung, shenmen, thalamus and hip points) or sham procedure (4 non-acupuncture points on the auricular helix). Permanent press AA needles were retained in situ 3 days after surgery. Postoperative pain was treated with intravenous piritramide (opioid receptor agonist with analgesic potency of 0.7 compared with morphine) using a patient-controlled analgesia (PCA) pump. The time to the first analgesic request, the amount of postoperative piritramide via PCA and pain intensity on a 100-mm visual analogue scale (VAS-100) were used to evaluate postoperative analgesia. Intraoperative anesthetic requirement, incidence of analgesia-related side effects, inflammation parameters and success of patients' blinding were also recorded. Fifty-four patients (29 AA and 25 controls) completed the study. Piritramide requirement during 36 h after surgery in AA group was lower than in control: 37+/-18 vs. 54+/-21 mg; mean+/-SD; P=0.004. Pain intensity on VAS-100 and incidence of analgesia-related side effects were similar in both groups. The differences between the groups as regard patients' opinions concerning success of blinding were not significant. Findings from our study demonstrate that AA could be used to reduce postoperative analgesic requirement.

Acupuncture Analgesia↗
PubMed2005

Successful treatment of extranodal Hodgkin's lymphoma in a patient with longstanding hairy cell leukemia.

Purine analogs, particularly pentostatin and cladribine, are highly effective in hairy cell leukemia (HCL). Both of these drugs induce responses in approximately 80-95% of patients. However, it is not yet determined if treatment with these drugs can induce second malignancies. Hodgkin's lymphoma is very rare as a second malignancy and there are only 3 reported cases concerning the association of this lymphoma with HCL. We describe a patient with longstanding HCL in complete remission after cladribine, in whom extranodal Hodgkin's lymphoma appeared 8 years after the diagnosis of HCL. Magnetic resonance imaging revealed diffuse intra-osseal neoplastic infiltration of the corpora of the whole spinal column and extra-osseal propagation from the fifth thoracic vertebra into the spinal canal with spinal cord compression. Histological and immunohistochemical analysis of the extradural tumor, which was completely excised, disclosed nodular sclerosis Hodgkin's lymphoma with typical Reed-Sternberg cells that were positive for CD30, CD15, bcl-6, Ki67, p53, EBV LPM-1 and IgG, and negative for CD45, CD20, DBA44, kappa, lambda light chains and IgM. In addition, immunohistochemical analysis of the bone marrow in 1999 showed infiltration with positivity for IgM and negative for kappa light chains and IgG. These findings (expression of different immunoglobulins and light chains on the cells) suggest an independent origin of these 2 B-cell neoplasms. After neurosurgery the patient received 6 courses of the MP-ABVD protocol and achieved a complete remission, which has lasted 16 months thus far.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2005

Inefficiency of storm water inlets as a source of urban floods.

The paper attempts to explain sources of surplus storm water runoff in urban areas, particularly in relation with functioning of inlets. Inlet capacity (quantity of captured water) and inlet efficiency (portion of the approaching flow rate) have been defined and their relationship with relevant parameters (approaching flow, longitudinal and lateral street slopes) was established through laboratory measurements. Effects of clogging of inlets on inlet capacity were also investigated in laboratory conditions. As a consequence of decreased inlet efficiency, there is a portion of approaching flow that is not captured by the inlet (pass-over flow). If the pass-over flow is considered along a street having numerous inlets, it is easy to estimate the quantity of flow that would accumulate on the pavement. Inlet inefficiency can be significant when overestimation of inlet capacity results in increased distance between consecutive inlets, and when clogging of grates or inadequate placing of inlets causes significant decrease in inlet capacity.

Cities↗
PubMed2004

Hypopituitarism as a consequence of traumatic brain injury (TBI) and its possible relation with cognitive disabilities and mental distress.

Recent studies have demonstrated that hypopituitarism, in particular GH deficiency, is common among survivors of traumatic brain injury (TBI) tested several months or yr following head trauma. We present the results of endocrine, neurological, neuropsychological and psychiatric evaluation in a group of 67 patients who suffered TBI at least one yr ago. Our study shows that decreased endocrine function is either restricted to one or more anterior pituitary hormones and is present in 34% of patients with any pituitary hormone deficit, while multiple pituitary hormone deficiencies are found in 10% of patients. GH/IGF-I axis was evaluated by GHRH+GHRP-6 test and IGF-I measurement. Severe GHD is the most frequent deficiency present in 15% of TBI patients. Gonadotrophin deficiency was present in 9% of patients with TBI, while thyrotroph and corticotroph function seemed more refractory to impairment. Patients with moderate-to-severe trauma are not necessarily more likely to have hypopituitarism than those with mild injury. Neuropsychological testing revealed a significant positive correlation of peak GH levels after GHRH+GHJRP-6 test with verbal learning and verbal short term memory (RAVLT total score p = 0.06, immediate free recall p = 0.02 and delayed free recall p = 0.04). Verbal and visual memory was significantly lower in elderly patients and in males. Visoconstructional abilities (RCF copy) were significantly lower in the elderly (p < 0.01) and undereducated (p = 0.02). Visual memory (free recall of complex figure after 30 min) significantly correlated with lower IGF-I levels (p = 0.01). Gonadotrophins and testosterone correlated significantly with visoconstructional abilities. Simple and complex conceptual tracking (TMT A and B) was significantly more impaired in older TBI patients (p < 0.01) and with longer time from trauma (TMT B only, p = 0.03). The psychiatric evaluation by using two different scales showed depression, phobic anxiety and psychoticism to be more prominent in the TBI group. Paranoid ideation and somatization negatively correlated with the peak GH responses to GHRH+GHRP-6 test (p = 0.04 and p = 0.03, respectively). Depression scale showed that nearly half of patients suffered from mild to moderate depression. The benefits of hormone replacement therapy on cognitive functioning and mental distress in TBI patients are eagerly awaited.

Adult↗
PubMed2004

[PercuTwist dilational tracheostomy. Prospective evaluation of 54 consecutive patients].

BACKGROUND: Percutaneous dilational tracheostomy (PDT) is considered to be an accepted method in intensive care patients. In 2002 Frova and Quintel described a method of dilation that employed controlled rotation of the PercuTwist dilational device. The goal of the present study was to evaluate the new technique employed by an experienced team. PATIENTS AND METHODS: Prospective, observational clinical study in 54 intensive care patients who required PDT. All tracheostomies were accompanied by bronchoscopic control. Vital parameters and perioperative complications were registered. RESULTS: In all 54 consecutive PercuTwist tracheostomies no severe complications were noted. Accidental tracheal ring fracture was noted in 7 patients while bleeding that needed surgical care occurred in 1 patient. CONCLUSION: The PercuTwist tracheostomy is a safe procedure for intensive care patients. More prospective studies that would compare the PercuTwist tracheostomy with the other PDT methods are necessary.

APACHE↗
PubMed2004

Biofeedback as a supportive method in weaning long-term ventilated critically ill patients.

Weaning a patient from mechanical ventilation is occasionally a difficult process complicated by the patient's emotional state. Anxiety, agitation, depression and other emotional disturbances can start a vicious circle between fear of losing breath and dyspnea that impairs the process of withdrawing ventilatory support. A biocybernetic loop model is suggested that integrates psychological variables (e.g., capacity of self-control, self-confidence, sense of self-efficacy) as important factors for a successful weaning. The paradigm of biofeedback is regarded as a suited approach to strengthen these psychological factors. It means the externalization of physiological functions especially of those from the autonomous nervous system so that a patient becomes aware of them. In the case of the ventilated patient, it is assumed that the transformation of the respiratory activities into perceptible (acoustic and visual) signals supports the patient's self-controlling behaviour during the weaning process. He gets positive reinforcement for his efforts to influence his breathing intentionally and, by continuous and immediate information, he regains self-confidence to control his somatic functions effectively. The application of biofeedback is mainly described in single case studies. They all report a decrease in the respiratory rate and an increase in the tidal volume. The need for a controlled study is suggested that would answer the question of whether biofeedback is an appropriate psychological tool to facilitate the weaning process in mechanically ventilated patients.

Biofeedback, Psychology↗
PubMed2002

Antioxidants modulate adenosine metabolism in rat mesangial cells cultured under high glucose conditions.

Glomerular mesangial cells play a major role in glomerular hemodynamics, considered also as antigen-presenting cells participating in immune response. Mesangial dysfunction and proliferation are typical lesions of diabetic glomerulopathy. Adenosine, a local hormone, produced by mesangial cells is a metabolic regulator of renal blood flow, capable of decreasing glomerular filtration rate (GFR), exerting immunosuppressive, antiproliferative and anti-inflammatory properties. Since it was well established that antioxidants confer protection against increased oxidative stress that occurs in diabetes, the effect of captopril, reduced glutathione and melatonin on adenosine metabolism was investigated. Glomerular mesangial cells obtained from collagenase treated glomeruli, isolated from renal cortex of Sprague-Dowley rats, were grown under high glucose conditions (30 mmol/L) as a model of diabetic microenvironment. The activity of adenosine metabolizing enzymes: 5'-nucleotidease (5'-NU) responsible for its production and adenosine deaminase (ADA) responsible for its degradation were investigated. Hyperglycemic conditions led to decreased adenosine production via 5'-NU and decreased removal via ADA. Captopril, given in therapeutic concentration induced enzyme activities in normoglycemic conditions and restored hyperglycemia-induced decrease. In order to investigate if the presence of SH groups may be responsible for this improvement, the cells were exposed to reduced glutathione, and it exerted almost equal effect, given in physiological and higher concentrations. Melatonin increased 5'-NU activity only in physiological glucose conditions. Presented results confirm potential renoprotective effect of SH-group containing antioxidant supplementation during diabetes in restoring adenosine metabolism.

Adenosine↗
PubMed2001

Dual role of interferon-gamma signalling pathway in sensitivity of pancreatic beta cells to immune destruction.

AIMS/HYPOTHESIS: Disruption of the interferon-gamma (IFN-gamma) signalling pathway at the level of interferon regulatory factor-1 (IRF-1) protects islets against cytokine-induced nitric oxide production and cell death in vitro. The aim of this study was to investigate the effects of a global disruption of IFN-gamma signalling, or a selective disruption of IRF-1, on beta-cell sensitivity to in vivo immune destruction. METHODS: In a first set of experiments, IFN-gamma receptor knockout mice (IFN-gammaR-/-) and interferon regulatory factor-1 knockout mice (IRF-1-/-) were rendered diabetic by injections of 50 mg streptozotocin i. p. on 5 consecutive days (MLDSTZ). RESULTS: Whereas no difference in sensitivity to MLDSTZ-induced diabetes could be observed between IFN-gammaR-/- mice and their 129/Sv/Ev controls (50% vs 55%, NS), there was an increased incidence of diabetes in IRF-1-/- mice (100% vs 67% in C57B1/6 mice, p < 0.05). A similar increased sensitivity to immune destruction of IRF-1-/- islets was observed when these islets were used as allografts. Islet graft survival rate of IFN-gammaR-/- and 129/Sv/Ev islets, when transplanted in alloxan-diabetic BALB/c recipients, was comparable (12.0 +/- 1.9 days vs 12.9 +/- 2.3 days, NS). Allograft rejection, however, of IRF-1-/- islets by BALB/c recipients occurred more rapidly than following transplantation to their C57B1/6 controls (9.1 +/- 2.0 days vs 13.1 +/- 1.5 days, p < 0.003). CONCLUSIONS/INTERPRETATION: These data indicate that IFN-gamma signal transduction at the beta-cell level is not essential for immune beta-cell destruction in vivo. Moreover, disruption of the IRF-1 gene in pancreatic islets increases susceptibility to beta-cell killing, suggesting that IRF-1 might be necessary for the expression of putative beta-cell "defence and/or repair" genes.

Animals↗
PubMed2001

Oxidative modification of rat liver 5'-nucleotidase: the mechanisms for protection and re-activation.

The effect of oxidative stress catalysed by transition metals appears to have a critical relevance for the structure and function not only of membrane lipids but also of integral membrane proteins in a complex lipid-protein assembling, and membrane-dependent function. The integral membrane enzyme 5'-nucleotidase is susceptible to Fe((2+))-ion catalysed oxidative modification, and the extent of enzyme inhibition is in inverse relationship (r = -0.820) with lipid peroxidation (MDA) level. This work is also a comparative study about possible effectiveness of different Fe-ion chelators (deferoxamine, Na-citrate, Na-salicylate, ammonium oxalate and EDTA), antioxidants (GSH, GSH/GSH-Px system, Cu, Zn-SOD and mannitol) and metal cations (Mg(2+) and Mn(2+)) to protect or restore Fe(2+)-ion induced 5'-nucleotidase inhibition and to suppress Fe(2+)-ion enhanced lipid peroxidation. Among the examined chelators it was only deferoxamine and Na-citrate that exerted a fully protective and reactivating ability; among the antioxidants it was only GSH; among the metal cations it was only Mn(2+). The ability to protect or restore 5'-nucleotidase activity and to diminish chain-induced lipid peroxidation is explicable in terms of: metal-binding ability, capacity of taking iron away from a biological molecule, or ability of transferring the damage to itself. After a short incubation period, the iron associated with enzyme or lipid hydroperoxides could be in a labile coordinative linkage, still able to interact with possible ligands or metal cations.

5'-Nucleotidase↗
PubMed2001

Distinction between interleukin-1-induced necrosis and apoptosis of islet cells.

Interleukin (IL)-1beta is known to cause beta-cell death in isolated rat islets. This effect has been attributed to induction of nitric oxide (NO) synthase in beta-cells and subsequent generation of toxic NO levels; it was not observed, however, in dispersed rat beta-cells. The present study demonstrates that IL-1beta induces NO-dependent necrosis in rat beta-cells cultured for 3 days at high cell density or in cell aggregates but not as single cells. Its cytotoxic condition is not explained by higher NO production rates but might result from higher intercellular NO concentrations in statically cultured cell preparations with cell-to-cell contacts; nitrite levels in collected culture medium are not a reliable index for these intercellular concentrations. Absence of IL-1-induced necrosis in rat alpha-cells or in human beta-cells is attributed to the cytokine's failure to generate NO in these preparations, not to their reduced sensitivity to NO: the NO donor GEA 3162 (15 min, 50-100 micromol/l) exerts a comparable necrotic effect in rat and human alpha- or beta-cells. In preparations in which IL-1beta does not cause beta-cell necrosis, its combination with gamma-interferon (IFN-gamma) results in NO-independent apoptosis, starting after 3 days and increasing with the duration of exposure. Because IFN-gamma alone was apoptotic for rat alpha-cells, it is proposed that IL-1beta can make beta-cells susceptible to this effect, conceivably through altering their phenotype. It is concluded that IL-1beta can cause NO-dependent necrosis or NO-independent apoptosis of islet cells, depending on the species and on the environmental conditions. The experiments in isolated human beta-cell preparations suggest that these cells may preferentially undergo apoptosis when exposed to IL-1beta plus IFN-gamma unless neighboring non-beta-cells produce toxic NO levels.

Animals↗