The Biomechanical Investigation of Osseointegration Levels in Titanium Implants Simultaniously Placed with Different Bone Grafts.

BACKGROUND: Dental implant-supported prostheses have been scientifically accepted and have been a common treatment choice in the case reconstructing of partial or total tooth loss. In additon, bone grafts (alloplast, xsenograft, allograft) are frequently used in implant and sinus lift surgical procedures. AIM: The aim of this study is to investigate the bone-implant osseointegration levels of titanium implants simultaniously placed with different bone grafts. MATERIALS AND METHODS: In the study, 32 female S. Dawley rats were divided into four groups. In the control group (n = 8), turned surface implants with a 2.5 mm diameter and a 4 mm length were placed in the tibia of the rats without the use of a graft material. In the experimental groups, bone cavities were opened in the tibias of the rats and a synthetic (alloplast) graft (n = 8), human allograft (n = 8), and bovine xsenograft (n = 8) were placed simultaniously with a 2.5 mm diameter and a 4 mm length turned surface titanium implants. The cavities in the experimental groups were opened with a 4 mm diameter and a 5 mm length. After 8 weeks of recovery, all rats were sacrificed at the end of the experimental period. The implants and surrounding bone tissue were removed. The removed tissue was subjected to biomechanical analysis in order to evaluate bone-implant osseointegration and peri-implant new bone formation. The Kolmogorov-Smirnov test, Kruskal-Wallis test, and Mann-Whitney U-test were used in the study. Significance was evaluated at the P < 0.05 level. RESULTS: In the biomechanical analyses, it was determined that there was no statistically significant difference between the control group and the other three groups in which different graft materials were applied in terms of bone-implant osseointegration (P > 0.05). In other words, in the biomechanical analyses, no statistical difference was found between any of the groups. CONCLUSIONS: As a result of this study, it can be thought that different graft materials can be successfully used in peri-implant-guided bone regeneration and may be an alternative to autogenous grafts.

The Investigation of Bone-Implant Connection and New Bone Formation in Fasting and High-Fatty Diet Rats.

BACKGROUND: Hyperlipidemia caused by a high-fat diet (HFD) has many adverse effects on the cardiovascular system, including vascular problems. In addition, a HFD also has significant adverse effects on bone health. AIM: The aim of this study is to examine bone-implant osteointegration and new bone formation in peri-implant defects in fasting and high-fatty diet applied rats. MATERIALS AND METHODS: In this study, 28 female Sprague Dawley rats were used. The rats were divided into four groups, with seven rats in each group: the control group on a normal diet (Group 1) (n = 7), the fasted group (Group 2) (n = 7), the high-fatty diet (HFD) group (Group 3) (n = 7), and the fasted and HFD group (Group 4) (n = 7). Titanium implants with a diameter of 2.5 mm and a length of 4 mm were placed in the right tibia bones of the subjects, and a bone graft corresponding to 2 mm of the implant length was placed in the bone defect applied to the neck region. All rats that continued the administered diet for 12 weeks were sacrificed at the end of the experiment period. The implants and surrounding bone tissue were surgically removed and subjected to biomechanical analysis to assess bone-implant osteointegration and peri-implant new bone formation. RESULTS: It was determined that there was no statistically significant difference between the rats in the control group and the other three groups in terms of bone-implant osteointegration and peri-implant new bone formation (P > 0.05). CONCLUSION: As a result of this study, it was determined that fasting or maintaining a HFD does not adversely affect bone-implant osteointegration or peri-implant new bone formation in the tibias of rats.

Histological evaluation of tissue reaction and new bone formation of different calcium silicate-based cements in rats.

BACKGROUND: The purpose of this study was to evaluate the local reactions and new bone formation of rat subcutaneous and bone tissue to different calcium silicate cements. METHODS: In this study, 80 rats were divided into five groups as control, BIOfactor MTA (BIO), NeoMTA Plus (NEO), MTA Repair Hp (REP), Biodentine (DENT) and then into two subgroups according to sacrification times (7, 30 days; n = 8). Polyethylene tubes filled with appropriate materials (test groups); empty tubes (control group) were implanted into the dorsum of each rat subcutaneously. For intraosseous implantation, materials were placed in the cavities created in tibia of rats. Subcutaneous tissue and tibia samples were stained with haematoxylin-eosin and subjected to histopathological analysis. A score (0-3) was used to grade inflammatory reaction and new bone formation. Data were analysed by Kruskal-Wallis and Mann-Whitney U tests (P < 0.05). RESULTS: Inflammatory reaction observed in subcutaneous and intraosseous tissues for 7 days decreased significantly in all groups over time (P < 0.05). It was determined that there was significant increase in new bone formation in REP, BIO, DENT groups over time (P < 0.05). CONCLUSION: Four contemporary bioceramic materials induced local inflammation and tissues changes shortly after subcutaneous implantation, which were reduced over time. In intraosseous implantation, all materials induced new bone formation over time. REGISTRATION NUMBER: ADJ-03-23-0134. © 2023 Australian Dental Association.

Does high fat diet effect the bone-implant connection?

OBJECTIVE: Obesity induced by a high fat diet is associated with chronic up-regulation of inflammatory cytokines which stimulate osteoclast activity and bone resorption. However, the role of high-fat diet on bone-implant connectivity has not been studied in detail. In this study, we investigated whether a high-fat diet (HFD) affects bone implant connection (BIC) in periimplant bone. METHODS: Twenty female Sprague Dawley rats were divided in two groups: 1) Control rats were fed with normal chow and titanium implants were integrated into tibial bones at the end of 3rd month and no treatment was applied 2) HFD group; rats were fed a high-fat diet (42 % of calories as fat), then the titanium implants were integrated into tibial bones at the end 3rd month. Following surgical integration of the implants, the rats were fed with control and HFD diets for 3 months. After the 6 months experimental period all rats were sacrificed and the implants and surrounded bone tissues were collected and the BIC was assessed histomorphometrically after the non-decalcifiing histological methods. Bone implant connection was detected with the ratio of the implant surface directly connected with the peri-implant bone tissues to the total implant surface length. RESULTS: Histologic analysis showed that HFD was not impaired BIC (p>0.05). CONCLUSION: In conclusion, within the limitation of this research, HFD did not effect the BIC rat tibias (Tab. 2, Fig. 2, Ref. 26). Text in PDF www.elis.sk.

An assessment of periodontal health in patients with schizophrenia and taking antipsychotic medication.

BACKGROUND AND OBJECTIVE: Severe periodontal disease is prevalent among patients with schizophrenia and is caused by the side effect of their medication, poor dental hygiene and smoking. The objective of this study was to evaluate whether the rate of periodontal disease could be modulated by changing the salivary flow rate (SFR) because of the use of antipsychotic medications in patients with schizophrenia. METHODS: Group A (n=33) included patients who used medications that may cause xerostomia, or dry mouth and Group B (n=20) included patients who used medications that may cause sialorrhea, an excessive secretion of saliva. The participants' periodontal status was assessed using the plaque index (PI), assessing bleeding on probing (BoP), probing pocket depth (PPD) and clinical attachment levels (CAL). RESULTS: The mean of PI and BoP was significantly higher in Group A than in Group B (P<0.001), but the PPD, CAL and decayed, missing and filled teeth (DMFT) scores were not significantly different in the two groups according to the statistical results (P>0.05). CONCLUSIONS: The researcher concluded that there is a high risk of periodontal disease among patients with schizophrenia, and there is an even higher risk of periodontal disease induced by medication that increased SFR. Preventive dental protocol should be increased during the dental health care of this disadvantaged patient group.

Effects of estrogen replacement therapy on vascular endothelial growth factor expression in choroidal and retinal vasculature.

PURPOSE: To investigate the effects of estrogen replacement therapy (ERT) on vascular endothelial growth factor (VEGF) expression in choroidal and retinal vasculature in experimental rat model. METHODS: Forty female Wistar rats were randomized in 4 groups in the study. Subcutaneous ERT (17beta-estradiol, 10 microg/kg/day) was administered for three months to first group without ovariectomy and to second group with ovariectomy. Rats in third group had only ovariectomy and fourth group had sham operation. At the end of the third month, all rats were sacrificed in estrous cycles determined by vaginal smear test and their right eyes were enucleated. Enucleated eyes were analyzed by immunohistochemical method for expression of VEGF. RESULTS: Only ovariectomy (group 3) in rats did not change VEGF expression than the sham operated (group 4) rats. However, there was more VEGF expression in groups receiving ERT than the group 3 and 4, but increased VEGF expression was statistically significant in group 1 in comparison to group 3, and 4 in both, choroidal and retinal vasculature. CONCLUSION: It was shown that ERT increases VEGF expression in choroidal and retinal vasculature, in particular in non-ovariectomized rats. Our findings suggest that ERT may be a risk factor for choroidal and retinal angiogenesis. Further studies are needed to evaluate the risks or benefits of exogenous estrogen supplementation for the choroidal and retinal angiogenesis in women (Fig. 2, Ref. 25).

Effects of sildenafil on blue-on-yellow and white-on-white Humphrey perimetry in 3 months regular use.

PURPOSE: To assess the effects of sildenafil on blue-on-yellow (B/Y) and white-on-white (W/W) Humphrey perimetry in a group of men with erectile dysfunction in 3 months regular use. METHODS: In this prospective study, 14 patients with erectile dysfunction received 50 mg doses of sildenafil (Viagra, Pfizer) two times per week regularly for 3 months. Patients underwent best-corrected visual acuity (BCVA), colour vision, anterior segment and fundus examination, and B/Y and W/W Humphrey perimetry in each eye before and after sildenafil treatment. Changes in mean deviations (MD) were compared separately for both eyes. RESULTS: No significant changes from baseline were observed in BCVA and colour vision after sildenafil treatment. The anterior segment and fundus examinations revealed no abnormalities. There was no change on B/Y and W/W Humphrey visual field. MD values of B/Y and W/W Humphrey perimetry remained nonsignificant for both eyes after 3 months regular use of sildenafil (P=0.133, and 0.092, respectively, for right, and P=0.221 and 0.925, respectively, for left eyes). CONCLUSION: Oral sildenafil used regularly for 3 months produced no effect on B/Y and W/W Humphrey perimetry.

Effect of sildenafil on ocular hemodynamics in 3 months regular use.

The aim of this study was to evaluate the effect of sildenafil on ocular hemodynamics in a group of men with erectile dysfunction in 3 months regular use. A total of 15 patients with erectile dysfunction were included in this prospective study. All patients received 50 mg doses of sildenafil (Viagra, Pfizer) two times per week regularly for 3 months. The following examinations were performed on both eyes before and after sildenafil treatment: best-corrected visual acuity (BCVA), intraocular pressure (IOP), color vision, anterior segment, and fundus examination. Using color Doppler imaging, we measured hemodynamic variables in the ophthalmic artery (OA), central retinal artery (CRA), and short posterior ciliary artery (SPCA). No significant changes in BCVA, color vision and IOP were found after sildenafil treatment. The anterior segment and fundus examinations showed no abnormalities. All Doppler parameters of OA, CRA, and SPCA remained nonsignificant for both eyes after sildenafil treatment. Oral sildenafil in 3 months regular use seems to have no effect on ocular hemodynamics.

The plasma levels of prostanoids and plasminogen activator inhibitor-1 in primary and secondary thrombocytosis.

An elevated platelet count is a common finding in both hospitalized and ambulatory patients. Thrombosis and bleeding complications are more frequently observed in patients with clonal thrombocytosis than secondary thrombocytosis. The aim of this study was to investigate the behaviors of plasminogen activator inhibitor type 1 (PAI-1), the inhibitor of fibrinolysis; and thromboxane A2 and 6-keto-PGF1 alpha, the products of endoperoxides, in 16 patients affected with clonal thrombocytemia as compared with 16 patients with reactive thrombocytosis and 15 normal controls. In the clonal thrombocytemia group, plasma levels of PAI-1 antigen and activity were significantly higher than both reactive thrombocytosis and control group. Plasma levels of 6-keto-PGF1alpha were significantly higher in the clonal thrombocytemia group than the other two groups and also higher in the reactive thrombocytosis group than the control group, which was also significant. This study confirms that arachidonate metabolism is frequently deranged in patients with thrombocytosis and hypofibrinolysis due to increased PAI-1 plasma levels as shown in the clonal thrombocytosis group. This may explain the thrombotic tendency in myeloproliferative disorders.

Plasma basic fibroblast growth factor and bone marrow fibrosis in clonal myeloproliferative disorders.

Basic fibroblast growth factor (bFGF) is an important growth factor involved in clonal hematopoietic expansion, neoangiogenesis, and bone marrow fibrosis, all of which are important pathobiologic features of clonal chronic myeloproliferative disorders (CMPD) and myelodysplastic syndromes (MDS). The aim of this study was to assess circulating bFGF concentrations in patients with CMPD and MDS with respect to the presence of bone marrow fibrosis in histopathologic examination. The study group comprised 18 patients with CMPD (six female, 12 male; median age 50 years), seven patients with MDS (one female, six male; median age 66 years) and 10 healthy adults as controls (four female, six male; median age 29 years). CMPD group included six chronic myelogenous leukemia (CML), seven essential thrombocythemia (ET), three polycythemia vera (PV), two agnogenic myeloid metaplasia (AMM). All seven MDS patients were the FAB subtype of refractory anemia (RA). Bone marrow biopsy sections stained with hematoxylin and eosin (H & E) and for reticulin were examined for the presence of fibrosis. The median plasma bFGF level was 18.2 pg/ml (interquartile range, IQR: 15.2-26.7) in patients with CMPD, 18.0 pg/ml (IQR: 15.8-26.4) in patients with MDS, 13.6 pg/ml (IQR: 9.9-20.0) in the control group. The bFGF levels were significantly higher in patients with CMPD in comparison with the healthy control group (P = 0.031). Circulating bFGF tended to be significantly lower in relation to the development of marrow fibrosis (P = 0.028). The complicated interactions of bFGF and fibrosis in the context of CMPD may be either 'cause' or 'effect'. The bFGF might represent an important link between angiogenesis, fibrosis, and clonal neoplastic hematopoiesis during the development of CMPD.

The predictability of factor V Leiden (FV:Q(506)) gene mutation via clotting-based diagnosis of activated protein C resistance.

After the discovery of activated protein C resistance (APCR) due to factor V Leiden mutation and the causal relationship of the phenomenon with clinical thromboembolism, a wide variety of functional clotting-based assays were developed for testing of APCR in relation to the specific DNA-based analysis of FV:Q(506) Leiden. The aim of this study is to assess a clotting-based APCR assay using procoagulant crotalidae snake venom with respect to the sensitivity, specificity, and predictability for the presence of the factor V Leiden mutation. APCR testing and factor V DNA analyses have been performed concurrently on 319 patient specimens. APCR values of the patients with homozygous factor V Leiden mutation (70.4+/-13.5 s) were significantly lower (p<0.001) in comparison to the subjects with the heterozygous mutation (87.6+/-13.4 s). The assay is highly sensitive (98.7%) and specific (91.9%) for the screening of factor V Leiden mutation. The sensitivity and specificity of the APCR testing reached to 100% below the cut-off value of 120 s among the patients with homozygous factor V Leiden mutation. Therefore, this method could help the desired effective optimal screening strategy for the laboratory search of hereditary thrombophilia focusing on the diagnosis of APCR due to FV:Q(506).

Protein C inhibitor and serum amyloid A in immune thrombocytopaenic purpura.

In immune thrombocytopaenic purpura (ITP), phagocytic cells prematurely destroy platelets opsonized by anti-platelet auto-antibodies, while residual platelets rescued from these autoimmune attacks are hyperfunctioning. The exact pathobiological basis of this phenomenon is unknown. Protein C inhibitor (PCI), a platelet alpha-granule pro-coagulant molecule, is released on activation of platelets. Serum amyloid A (SAA; an acute phase protein), however, inhibits platelet aggregation and modulates platelet adhesion. We aimed to assess circulating soluble plasma PCI and SAA concentrations in 17 patients with newly diagnosed ITP and ten healthy volunteers. Plasma PCI concentrations tended to be higher in ITP patients, despite absolute thrombocytopaenia, than in normal controls. SAA levels were significantly higher in ITP patients compared with the control group. We conclude that secretion of the alpha-granule PCI content of platelets could result from platelet activation, and that PCI may be the link between platelet microparticles and haemostatically active ITP platelets. Increased concentrations of SAA and PCI may interfere with the disordered and compensatory pro-coagulant mechanisms of ITP.

Gonadotropin treatment increases homocysteine levels in idiopathic hypogonadotropic hypogonadism: an indirect effect mediated by changes in body composition.

The main objective of the present study was to examine the alterations in plasma total homocysteine (tHcy) concentrations during a testosterone-deficient state and after gonadotropin treatment for 6 Months in patients with idiopathic hypogonadotropic hypogonadism (IHH). Thirty-five newly diagnosed male patients with IHH (mean age 21.34+/-1.53 years) and 29 age- and body mass index-matched healthy males (mean age 21.52+/-1.77 years) were recruited into the study. Pretreatment levels of free testosterone (1.51+/-0.66 pg/ml), estradiol (21.37+/- 4.37 pg/ml), FSH (0.91+/-0.24 IU/l) and LH (1.25+/- 0.53 IU/l) were lower than controls (25.17+/-3.06 pg/ml, 31.00+/-4.96 pg/ml, 3.14+/-1.62 IU/l and 4.83+/-1.65 IU/l respectively) (P<0.001). They increased significantly after treatment (18.18+/-1.59 pg/ml, 27.97+/- 4.25 pg/ml, 2.41+/-0.27 IU/l and 2.79+/-0.19 IU/l respectively) (P<0.001). Patients with IHH had lower tHcy levels than controls (10.14+/-1.34 and 12.58+/- 2.29 micro mol/l respectively) (P<0.001). Plasma tHcy concentrations increased significantly (12.63+/-1.44 micromol/l) after 6 months of treatment (P<0.001). As compared with the controls, pretreatment levels of serum creatinine (63.54+/-13.01 vs 82.84+/-16.69 micromol/l), hemoglobin (12.98+/-0.56 vs 13.83+/-0.71 g/dl) and hematocrit (39.29+/-2.01 vs 41.38+/-1.95%) were significantly lower (P<0.001), and they increased significantly following treatment (80.24+/-11.93 micromol/l, 13.75+/-0.49 g/dl and 41.26+/-1.78% respectively) (P<0.001). The pretreatment folic acid and vitamin B(12) levels were significantly higher in patients when compared with controls (14.87+/-5.68 vs 12.52+/-4.98 nmol/l, P=0.034 and 289.75+/-92.34 vs 237.59+/-108.17 pmol/l, P=0.002 respectively). They decreased significantly after treatment (11.29+/-3.31 nmol/l and 228.51+/-54.33 pmol/l respectively) (P<0.001). The univariate and multivariate regression analysis results showed that only changes in creatinine, creatinine clearance, vitamin B12 and folic acid were independently associated with changes in tHcy levels in patients with IHH. In conclusion, the increase in plasma tHcy concentrations following gonadotropin treatment seems to be largely independent of changes in androgen levels.

Rational use of the PFA-100 device for screening of platelet function disorders and von Willebrand disease.

Two hundred and five patients referred for evaluation of platelet functions and 126 healthy controls were tested with the PFA-100 instrument. A cut-off value of 150 s for collagen/epinephrine (CEPI) closure time (CT) produced most acceptable sensitivity (90%), specificity (85.2%), and positive (82.6%) and negative (91.6%) predictivity values for screening of platelet function disorders and von Willebrand disease (vWD). All patients with vWD and Glanzmann thrombasthenia could be detected by PFA-100. Both CEPI and collagen/adenosine diphosphate (CADP) CTs were elevated in all of these cases. Sensitivity of the device was 81.6% for patients with platelet secretion defects. CADP CT was normal in 63.9% of the patients in this subgroup. Specificity (47%) and positive predictivity (57%) of the instrument were diminished in patients with low hemoglobin concentrations. Depending on the results, an algorithm was developed for screening of platelet function disorders and vWD with PFA-100.

Two common genetic thrombotic risk factors: factor V Leiden and prothrombin G20210A in adult Turkish patients with thrombosis.

The prevalence of genetic risk factors for thrombosis varies greatly in different parts of the world, both in patients with thrombosis and in the general population. Factor V Leiden (FVL) and prothrombin G20210A (PT G20210A) mutations are the most common genetic defects leading to thrombosis. We have previously reported that those two thrombotic risk alleles are frequently found in Turkish children with thrombosis. The aim of the present study was to investigate the frequency of FVL and PT G20210A and their clinical manifestations in adult Turkish patients with thrombosis. Between January 1997 and February 2000, 146 patients with documented thrombosis were investigated in our center for the presence of the FVL and PT G20210A mutations. Forty-five of 146 patients with thrombosis (30.8%) were detected to have FVL mutation. Among those cases with the FVL mutation, seven (4.8%) had homozygote and 38 (26%) had heterozygote mutation. The PT G20210A mutation was detected in 10 of the 146 patients with thrombosis (6.8%). Another six cases (4.1%) had both FVL and PT G20210A mutations. The overall frequency of these two common risk alleles in our adult population with thrombosis was 41.6%. Our findings reveal that FVL and PT G20210A mutations are significant genetic risk factors contributing to the pathophysiology of thrombosis in the Turkish population.

Cytokines, endothelium, and adhesive molecules in pathologic thrombopoiesis.

Clonal thrombocytosis (CT) associated with myeloproliferative disorders (MPD) is believed to be secondary to autonomous unregulated platelet production. Secondary or reactive thrombocytosis (RT) can be observed in a number of clinical circumstances and may be related to persistent production of some thrombopoietic factors acting on megakaryocytes (MK). The goal of this study is to assess the serum concentrations of these cytokines in control subjects and patients with MPD associated with thrombocythemia, RT, and autoimmune thrombocytopenic purpura (ATP). Eleven patients with MPD, five with chronic myeloid leukemia (CML), three with polycythemia vera (PCV), two with essential thrombocythemia (ET), one with myelofibrosis, 15 with RT, eight with ATP, and 12 healthy volunteers were enrolled in the study. Serum interleukin (IL)-1beta, IL-6, tumor necrosis factor-alpha (TNF), fibronectin, intracellular adhesion molecule-1 (ICAM-1), and thrombomodulin (TM) were measured in these groups. Interleukin- 1beta, IL-6, and TNF levels were high in patients with RT and ATP, suggesting that these cytokines act on early uncommitted progenitors, promoting commitment along the MK lineage and leading to thrombocytosis or compensation for thrombocytopenia. TM was significantly increased in patients with MPD compared to all other groups, probably indicating the presence of subclinical endothelial damage. Fibronectin levels were high in MPD and RT patients. This finding can be secondary to high platelet turnover in these patients. We found that ICAM-1 levels were high in patients with clonal thrombocytosis. ICAM-1 can be one of the factors initiating the events ultimately leading to clonal thrombocytosis. Thrombocythemia associated with MPD is an autonomous phenomenon not regulated by cytokines.

Cardiac and great vessel thrombosis in Behçet's disease.

Behçet's disease (BD) is a chronic relapsing systemic vasculitis in which orogenital ulceration is a prominent feature. The disease affects many systems and causes hypercoagulability. We present a 27-year-old male patient who exhibited widespread great vessel thrombosis including right atrial and ventricular thrombi in the setting of right-sided infectious endocarditis and orogenital aphthous ulcerations and erythema nodosum due to BD. We reviewed the enigmatic prothrombotic state of BD, and discuss our prior experiences in this field.

Evaluation of side effects of sildenafil in group of young healthy volunteers.

We evaluated the safety and side effects of sildenafil in a group of sexually active volunteers younger than 40 years under conditions without sexual stimulation. Single oral dose of 50 mg dildenafil (n = 20) or placebo (n = 20) was randomly administered to 40 sexually active volunteers with the mean age of 26.80 +/- 5.29 in sildenafil group and 25.70 +/- 4.95 in placebo group. All the subjects were informed about the study, but not about the medicine. The following tests were performed immediately before and 90 minutes after the administration of the medicine: resting heart rate, blood pressure, electrocardiogram, visual acuity, color vision. The subjects were also asked to describe any discomfort or difference. Mann Whitney U test was used for statistical analyses. The only statistically significant difference was between heart rates before and after the administration of the sildenafil (p = 0.02). Color vision, visual acuity tests yielded no differences. The decrease in blood pressure was not significant. The most common side effects were flushing (75% and 0%), headache (50% and 5%), dyspepsia (15% and 5%), unintentional incomplete sexual arousal (15% and 0%) and palpitation (15% and 10%) in groups of sildenafil and placebo, respectively. The only serious side effect requiring medical treatment was arthralgia on the knee in one subject. Although these side effects can be acceptable, the likelihood of these side effects needs to be made clear to potential users of this medication.

Effect of sildenafil on ocular haemodynamics.

PURPOSE: To study the effect of sildenafil, which is an effective agent for the treatment of erectile dysfunction, on ocular haemodynamics. METHODS: In this prospective study we examined the effect of a single oral dose of 50 mg sildenafil (Viagra) in a group of healthy young male volunteers, by using colour Doppler ultrasound imaging to measure haemodynamic variables in the central retinal artery (CRA), short temporal posterior ciliary artery (STPCA) and ophthalmic artery (OA). The following examinations were performed on both eyes immediately before and 1 h after a single oral dose of 50 mg sildenafil: visual acuity, intraocular pressure (IOP), colour vision, anterior segment, fundus appearance, resting heart rate, blood pressure and colour Doppler measurements. RESULTS: After sildenafil administration, peak systolic velocity, mean velocity and end-diastolic velocity significantly increased in the OA of both eyes. All Dopper indices remained non-significant for the CRA and STPCA of both eyes. Sildenafil did not cause any significant change in IOP, colour vision, visual acuity, systolic blood pressure or diastolic blood pressure. However, heart rate measurements increased significantly after sildenafil administration compared with baseline (p = 0.003). CONCLUSION: The increased flow velocity in the ophthalmic artery seems to be due to a vasodilator effect of sildenafil.

Mature ovarian teratoma as a possible cause of fever and clinical exacerbation in Behçet's disease: a case report.

Abstract Behçet's disease (BD) is a chronic relapsing systemic vasculitis of unknown etiology. BD is very rarely associated with neoplastic diseases. We report the case of a 39-year-old woman who had been treated for BD for 3 years. She presented with relapsing oral and genital lesions and persistent high-grade fever which had lasted for 1 month. The possible cause of the exacerbation of BD and fever in this patient was a mature ovarian teratoma. To our knowledge this is the first report of a patient with BD associated with a ovarian teratoma.