Colour agreement between try-in paste and resin cement: effect of background on zirconia-reinforced lithium silicate

PURPOSE

To investigate colour agreement between different shades of Panavia V5 resin cement and their try-in pastes under zirconia-reinforced lithium silicate ceramics.

METHODS

Forty-four zirconia-reinforced lithium silicate ceramic specimens were prepared at 0.8 ± 0.01 mm thickness. Composite resin tooth-shaded background specimens were obtained in two shades. Resin cement specimens were fabricated at 0.1-mm thickness. Colour difference values (ΔE) between Aquagel and both the try-in paste and resin cement were calculated using the CIE-Lab system. The CIEDE2000 (ΔE00) colour formula was used to determine colour differences. The three-way ANOVA test and a multiple comparisons test were used for statistical analysis (α = 0.05).

RESULTS

A statistically significant difference was found between the ΔE00 values obtained from the cement shade colour measurements for all specimens (P < 0.05). According to the three-way ANOVA test, lower ΔE00 values were observed in the try-in paste group compared to the resin cement group. The ΔE00 values were significantly affected by the cement shade and tooth-shaded background (P < 0.05).

CONCLUSIONS

The colour agreement between the try-in pastes and the corresponding resin cement differed, and the try-in pastes could not mask the dark dental background as much as the corresponding resin cement.

Detection of Candida dubliniensis in oropharyngeal samples of Turkish HIV-positive patients

The incidence of Candida dubliniensis in immunocomprimised patients in Turkey has not yet been determined. In this study the presence of C. dubliniensis in oral rinse samples of human immunodeficiency virus (HIV)-positive patients and healthy controls were investigated. Phenotypic tests like inability of growth at 45 degrees C, colony formation on Staib agar, intracellular beta-D-glucosidase activity, carbohydrate assimilation profiles and polymerase chain reaction with species-specific primers (DUBF and DUBR) were carried out for differentiation of C. dubliniensis. Of the 35 patients, four (11.4%) had C.dubliniensis in their oral cavity. Antifungal susceptibility testing of these C. dubliniensis isolates showed fluconazole MICs ranging from <0.06 to 32 microg ml(-1) and amphotericin B from <0.06 to 0.25 microg ml(-1). One isolate was dose-dependently susceptible to fluconazole (32 microg ml(-1)). This study demonstrates C. dubliniensis in HIV-positive patients from Turkey.

Candida carriage and Candida dubliniensis in oropharyngeal samples of type-1 diabetes mellitus patients

The carriage of Candida dubliniensis in the oral cavities of type-1 diabetic patients were investigated. Of 230 patients 81 (35%) had Candida spp. in their oral cavity; C. albicans was the most frequently isolated species (58%). No C. dubliniensis was found in the study population.

Effects of supplemental L-carnitine in drinking water on performance and egg quality of laying hens exposed to a high ambient temperature

The present study was conducted to investigate effects of L-carnitine supplied with drinking water on performance and egg quality of laying hens under high environmental temperature. In the study, 47-week-old laying hens (Brown hisex) were divided into two groups (control and treatment) and fed with a standard layer diet. Treatment group was received 50 p.p.m L-carnitine with drinking water for an 8-week period. Throughout the study, 8 h hot (35-37 degrees C) and 16 h thermoneutral (20-22 degrees C) environmental temperature regime was employed daily. The results showed that L-carnitine supplementation affected some egg quality characteristics of layers under high environmental temperature. Relative albumen weight and height were increased (p < 0.05) by supplemental L-carnitine. Live weight gain, feed intake, egg mass, egg weight, yolk weight, shell weight, yolk index, egg-shape index, yolk colour score and shell thickness were not affected (p < 0.05) by L-carnitine. It is concluded that L-carnitine supplementation in laying hens could have potential to improve albumen quality under high environmental temperature.

Is there a role of angiotensin-converting enzyme gene polymorphism in the failure of arteriovenous femoral shunts for hemodialysis?

In humans, thrombosis and neointimal hyperplasia are the major factors responsible for prosthetic graft occlusion. Previous studies suggest that the renin-angiotensin system is one of the key enzymes in the vascular system and has been implicated in the pathogenesis of thrombosis and neointimal hyperplasia. We conducted a case-control study to determine the frequency of the different angiotensin-converting enzyme (ACE) genotypes among the patients who had PTFE graft implantation for hemodialysis access. Between 1997 and 1999, 30 graft implantations were performed. Twelve individuals (40%) developed thrombotic complications, 8 of the 12 patients had ACE ID polymorphism, and 2 patients had DD and 2 patients had II polymorphism. The ID polymorphism was significantly more frequent in the thrombosed arteriovenous (A-V) grafts than in nonthrombosed A-V grafts (chi2 = 7.57 and p = 0.02). Overall, the frequency of the D and I alleles was 66.6 and 33.3%, respectively. In conclusion, ID polymorphism of the ACE gene plays an important role in the pathogenesis of vascular access thrombosis in subjects undergoing hemodialysis for chronic renal failure.

In vitro Candidacidal effect of polymorphonuclear neutrophils of Behçet's patients with or without ocular involvement

In this study our objective was to evaluate the in vitro candidacidal effect of polymorphonuclear neutrophils of Behçet's patients with or without ocular involvement (inactive phase). Fifteen patients with ocular involvement and 15 patients without ocular involvement were studied. Candidacidal assay was performed to assess the in vitro killing of Candida species by the polymorphonuclear neutrophils of both the study and control groups. In brief, peripheral venous polymorphonuclear neutrophils of healthy volunteers and patients with Behçet's disease were obtained by density gradient centrifugation. These cells were incubated with Candida spp. (Candida albicans, Candida tropicalis, Candida glabrata) for 3 h. Samples were seeded onto yeast extract peptone dextrose agar, incubated at 25 degrees C in a 5% humidified incubator for another 48 h, and formed colonies were counted. There was no significant difference between the candidacidal activity of polymorphonuclear neutrophils of healthy volunteers and of Behçet's patients with or without ocular involvement. Although various immunological abnormalities are reported in Behçet's disease, in vitro killing of Candida spp., which is one of the parameters for the phagocytic function of polymorphonuclear neutrophils, was not affected.

Vacuolating cytotoxic activity of 40 Helicobacter pylori strains isolated from Turkish patients

In this study we examined the in vitro vacuolating cytotoxic activity of Helicobacter pylori, which is a gram-negative microaerophilic curved bacterium and a causative agent of gastritis, peptic ulcer and gastric ulcer. A vacuolating cytotoxin assay was performed to assess the vacuolating activity of 40 strains (20 gastritis, 11 gastric ulcer, and 9 duodenal ulcer), which were obtained from patients undergoing upper gastrointestinal endoscopy. The Vero cell line was used in the cytotoxic assay. Of the 40 isolates, 24 (12 gastritis, 6 gastric ulcer, 6 duodenal ulcer) were cytotoxic for the Vero cell line at 1:4 and 1:8 dilutions. Thus, vacuolating cytotoxin of H. pylori affects the Vero cell line, but it seems there is no correlation between the positivity of the strains and the risk of any particular H. pylori disease.

Obstructive jaundice promotes bacterial translocation in humans

BACKGROUND/AIMS

Significant bacterial translocation was demonstrated following experimental biliary obstruction, however very little is known about the importance and the prevalence of gut-origin sepsis in obstructive jaundice patients. Therefore, the aim of this study was to investigate the concept of gut-origin sepsis in obstructive jaundiced patients and its clinical importance.

METHODOLOGY

Twenty-one patients requiring laparotomy for obstructive jaundice (group I) and thirty patients operated on electively mainly for chronic cholecystitis (group II) were studied. Peritoneal swab, mesenteric lymph node, portal venous blood, liver wedge biopsy and bile were sampled for culture immediately after opening the peritoneum. Additionally, peripheral blood samples were taken pre- and post-operatively from all patients. Post-operatively, patients were monitored for infectious complications.

RESULTS

The mean serum bilirubin concentration, gamma glutamyl transferase and alkaline phosphatase levels in jaundiced patients before therapeutic intervention were significantly higher than in control patients. Five patients demonstrated bacterial translocation in group I (24%), whereas only one did so in group II (3.5%, p < 0.05). Septic complications were detected in three patients, but only in two with bacterial translocation in group I. There was one patient with bacterial translocation who had septic complication in group II.

CONCLUSIONS

The present study demonstrated that obstructive jaundice significantly promotes bacterial translocation in humans, however, its clinical importance has yet to be defined.

Does pneumoperitoneum cause bacterial translocation?

Although extensive research has been carried out on the respiratory and renal effects of intra-abdominal pressure increase, there is limited research with regard to its effects on bacterial translocation. The objective of this study was to discuss whether the high intra-abdominal pressure due to carbon dioxide (CO2) insufflation during laparoscopy leads to bacterial translocation. Eighteen male dogs, 7 of which constituted the control group, were used in the study. Two study groups, in which the intra-abdominal pressure was raised to 15 mm Hg and kept at that level for 30 and 120 minutes, respectively, were set. Blood gases and blood pressure values were observed throughout the experiments. Samples of peritoneal smear, portal vein blood, mesenteric lymph node, liver, spleen, and cecum were examined to detect bacterial translocation. Histopathological examinations of all samples were also carried out. No translocation was detected in the samples of peritoneal smear, portal blood, mesenteric lymph node, liver, or spleen, but in the samples of cecum, bacterial colonization for the second group (p<0.05) and for the third group (p<0.05) was significantly higher compared with the control group. There was a considerable difference between the second and third groups (p<0.05). The changes in the mesenteric lymph nodes were interpreted to be a result of bacterial drainage. Histopathological examination disclosed active changes in the mesenteric lymph nodes in all groups, but there was considerable sinus histiocytosis only in the third group. We conclude that the intraabdominal pressure of 15 mm Hg created by carbon dioxide insufflation does not lead to bacterial translocation but causes intraluminal bacterial colonization in the cecum after 30 minutes and after 2 hours.

Aggressive bowel preparation does not enhance bacterial translocation, provided the mucosal barrier is not disrupted: a prospective, randomized study

PURPOSE

Prospective, randomized studies have shown that bowel preparation may adversely affect infectious complications following colonic resections. However, very little is known about the effects of bacterial translocation on these infectious complications. The aim of this prospective, randomized study was to assess the effects of bowel preparation on bacterial translocation.

METHODS

A total of 82 consecutive patients undergoing elective abdominal operations were randomly assigned to four groups: control (I; n = 20), mechanical (II; n = 21), mechanical plus oral metronidazole (III; n = 20), and polyethylene glycol preparation (IV; n = 21). Patients with intra-abdominal infection, those receiving preoperative antibiotics for any reason, and those having lower gastrointestinal tract disease were excluded from the study. Peritoneal swab, ileocecal and pericolic mesenteric lymph nodes, liver wedge biopsy, portal venous blood, and peripheral blood samples were taken for culture. Patients were followed up for postoperative infectious complications. Groups were matched according to age, gender, body surface area, and Acute Physiology and Chronic Health Evaluation II scores.

RESULTS

Bacterial translocation was identified by a positive culture in one patient in Group I, two in Group II, one in Group III, and three in Group IV, respectively. Differences in number of positive cultures among the groups were not statistically significant. Nine patients had major infectious complications. Only two had bacterial translocation, and the same micro-organisms grew in both patients, in one at the wound site and in the other at the cyst abscess.

CONCLUSION

This study demonstrated that mechanical bowel preparation does not enhance the spontaneous occurrence of bacterial translocation in patients without any clinical signs of lower gastrointestinal tract disease.

The effects of vagotomy on bacterial translocation: an experimental study

The effects of truncal vagotomy and proximal gastric vagotomy on bacterial translocation in rats were investigated in this experiment. The rats were divided into three groups. Only esophageal and gastric manipulations were performed in the control group (Group I). The anterior and posterior vagi were found and 0.5- to 1-cm pieces were taken out in the truncal vagotomy + pyloric dilatation group. In addition, pyloric dilatation was performed using a Fogarty catheter (Group II). The branches of the vagi, which lead to the rumen and corpus, were first tied with 5/O silk and then resected in the proximal gastric vagotomy group (Group III). All animals were sacrificed on the 7th day. Qualitative and quantitative tissue cultures of cecum, liver, spleen, mesenteric lymph node, and blood from vena cava were taken and a tissue sample from the ileum was obtained for histopathological examination with light microscopy. At the end of microbiologic study, the bacterial concentration on the cecal wall was 10.68 x 10(8) in the truncal vagotomy group, while it was 0.53 x 10(8) in the proximal gastric vagotomy group. Bacterial translocation was observed more in vagotomy groups than in control groups on the mesenteric lymph node, liver, and spleen. Bacterial translocation was greater in the truncal vagotomy group than in the proximal gastric vagotomy group (P < 0.05). Bacterial translocation was observed mostly in the liver, spleen, and mesenteric lymph node in the proximal gastric vagotomy group. No microorganisms could be cultured on systemic blood cultures. Cultures were positive only for one rat in the proximal gastric vagotomy group and for two rats in the truncal vagotomy group. At the end of histopathologic examination, when histopathologic parameters given for each rat were calculated, they were 5.44 +/- 2.12 in the truncal vagotomy group and 4.77 +/- 2.12 the in proximal gastric vagotomy group. The difference between these two groups was statistically significant (P < 0.05). Thus, there was damage to the intestinal wall in vagotomy groups, and it was greater in the truncal vagotomy group than in the proximal gastric vagotomy group. It was observed that bacterial translocation occurs after vagotomy, that this translocation occurs more after truncal vagotomy than after proximal gastric vagotomy, and that the translocation that occurred after vagotomies was not effective enough to create bacteremia.

[Microorganisms isolated from chronic suppurative otitis media and their antimicrobial sensitivities]

In this study mycologic and bacteriologic cultures were made in 100 patients who had chronic suppurative otitis media. We observed 58.8% pure, 35.3% mixed growth (more than one bacteria or bacteria and fungus) in the cultures. In pure cultures, we found mostly Proteus sp., S. aureus and Pseudomonas sp. respectively. In 134 bacteriologic cultures most frequently isolated bacteria was S. aureus (36.6%). In Sabouraud agar, we found mostly Aspergillus sp. and Candida sp. (28.6%). In antimicrobial sensitivity test, gram negatives were found to be sensitive mostly to ofloxacin (73.5%), pseudomonas was found to be sensitive mostly to tobramycin (70%). In the staphylococci the antimicrobic which had the highest sensitivity rate was gentamicin (75.5%), but at the same time we observed 24.5% resistance to this antimicrobic agent. Following this respectively, ofloxacin 71.4% sensitivity 4.1% resistance, cefuroxime 69.4% sensitivity 10.2% resistance rate were detected.