Kayhan Çağlar

The seroprevalence of Helicobacter pylori and nitric oxide in acne rosacea

Background Acne rosacea is a dermatosis with unknown etiology. Some studies have reported a high prevalence of Helicobacter pylori infection in acne rosacea. Other studies have reported a decrease in the severity of the lesions of acne rosacea after eradication of H. pylori. H. pylori is a Gram‐negative bacterium which colonizes the gastric mucosa and increases the synthesis of oxygen radicals, such as superoxide and proinflammatory cytokines. These cytokines have been demonstrated to stimulate the synthesis of the inflammatory species nitric oxide (NO). In this study, we examined the role of NO in the possible effect of H. pylori in acne rosacea.

Nosocomial fungemia due to Trichosporon asteroides: firstly described bloodstream infection

Trichosporon spp. are oppurtunistic yeasts that cause deep-seated, mucosa-associated, and superficial infections in immunocompromised patients. It is well known that Trichosporon asteroides is mainly responsible of superficial infections and does not cause systemic infections in humans so far. In this study, we present the first case of disseminated infection due to Trichosporon asteroides in an intensive care patient. Yeast colonies were isolated from the specimens of blood, urine, aspiration fluid of the endotracheal tube and catheter tip swabs of the patient. Conventional mycological studies were not adequate for the identification of the isolate to the species level. The genetic identification of the yeast isolate was performed and the DNA sequence of the isolate exactly matched the corresponding sequence of the Trichosporon asteroides rRNA gene from the GenBank DNA database (accession numbers: AB018017, AF075513). Therefore, our isolate was identified as Trichosporon asteroides as a causative agent of deep-seated fungemia.

Probiotic Agent Saccharomyces boulardii Reduces the Incidence of Lung Injury in Acute Necrotizing Pancreatitis Induced Rats

BACKGROUND Acute necrotizing pancreatitis is a severe acute inflammatory disease of the pancreas that can lead to extrapancreatic organ involvement. Supervening lung injury is an important clinical entity determining the prognosis of the patient. Probiotics are dietary supplements known to reduce or alter inflammation and inflammatory cytokines. In the present study, we hypothesize that probiotics may reduce lung injury by reducing bacterial translocation, which results in reduced infection, inflammation, and generation of proinflammatory cytokines in an experimental model of acute necrotizing pancreatitis. METHODS Pancreatitis was induced by concomitant intravenous infusion of cerulein and glycodeoxycholic acid infusion into the biliopancreatic duct. Saccharomyces boulardii was used as the probiotic agent. Rats were divided into three groups: sham, pancreatitis-saline, which received saline via gavage at 6 and 24 h following the pancreatitis, pancreatitis-probiotics, which received probiotics via gavage method at 6 and 24 h following the pancreatitis. The rats were sacrificed at 48 h, venous blood, mesenteric lymph node, pancreatic and lung tissue samples were obtained for analysis. RESULTS Serum pancreatic amylase, lactate dehydrogenase, secretory phospholipase A(2), and IL-6 were found to be increased in pancreatitis-saline group compared with the other groups (P < 0.05). Histological analyses revealed that edema, inflammation, and vacuolization as well as polymorphonuclear leukocyte infiltration in the lung tissue was significantly reduced in the probiotic treated group. Bacterial translocation was significantly reduced in the probiotic treated group compared with the other groups (P < 0.05). CONCLUSION These results suggest that Saccharomyces boulardii reduce the bacterial translocation. As a result of this, reduced proinflammatory cytokines and systemic inflammatory response was observed, which may be the reason underlying reduced lung injury in acute necrotizing pancreatitis.

African dust-laden atmospheric conditions activate the trigeminovascular system

It has been recently noticed that dust originating from deserts can be transported to other continents by the atmosphere and has an adverse effect on public health, such as increased asthma attacks. Dust originating from the Saharan Desert could initiate a series of reactions upon contact with cloud water and results in the formation of reduced iron (Fe2+), oxalate and various basic amino acids. We aimed to evaluate whether the simulation of Saharan dust-containing atmospheric conditions could trigger the trigeminovascular system. Freely moving rats incubated within simulated atmospheric conditions containing (i) Saharan dust, (ii) Co60 gamma ray-treated Saharan dust (sterilized) and (iii) dust-free air, were investigated for the presence of c-fos expression in trigeminal nucleus caudalis (TNC) and for NOx (nitrate+nitrite) levels in blood samples. Atmospheric samples were analysed for microorganisms. Saharan dust-containing atmospheric conditions induced c-fos expression in nociceptive neurons within TNC. The number of c-fos+ neurons in superficial lamina of TNC was significantly higher in the Saharan dust group (32.9 ± 5.3, P = 0.0001) compared with dust-free air (11.02 ± 2.7) or Co60-treated Saharan dust groups (15.01 ± 2.4). An increase in NOx levels was detected in blood samples of rats exposed to Saharan dust-containing atmosphere. This study has revealed an unknown environmental factor as a possible trigger for headache. It is the first time that transport of Saharan dust with the atmospheric air stream has been documented to be able to trigger the trigeminovascular system in animals. Further studies are needed to explore the mechanisms and molecules that mediate the nociceptive effect and to guide new treatment strategies.

Disseminated cryptococcosis in a human immunodeficiency virus-negative patient: a case report.

Cryptococcus neoformans is a widely distributed saprophytic fungus that may cause opportunistic infections in normal and immunocompromised individuals particularly in patients with HIV infection. Disseminated infection in HIV‐negative individuals is occasionally seen: a 57‐year‐old HIV‐negative Turkish female initially presented with enlarged mediastinal lymph nodes and a large pulmonary parenchymal nodule, eventually diagnosed with disseminated cryptococcosis and tuberculosis.

Effect of monophosphoryl lipid A on antibody response to diphtheria toxin and its subunits

Monophosphoryl lipid A (MPL) was evaluated for its ability to enhance the antibody response to diphtheria toxin and its fragment A and fragment B subunits. BALB/c mice were immunized subcutaneously with 1 Lf of diphtheria toxoid in the presence of 25 μg of MPL on days 0 and 14. Two weeks after the second immunization, sera were obtained from the mice and analysed for antibody response to diphtheria toxin and its subunits. A new ELISA method, developed in our laboratory, was used to measure antibody levels against the toxin, fragment A, and fragment B. It was observed that MPL significantly enhanced antibody responses to diphtheria toxin and its subunits. However, there was no statistical difference between anti‐A and anti‐B responses. The results indicated that MPL seems to be a potential candidate as an adjuvant for future diphtheria vaccine formulation.

Determinants of Protection against Diphtheria in Adult Hemodialysis Patients

Diphtheria is of great epidemiological concern. Although mainly observed during childhood, unvaccinated adults and relatively immunocompromised patients are at increased risk for acquiring diphtheria. We aimed to determine the rates and certain determinants of protection against diphtheria in adult hemodialysis (HD) patients. Protection rates of 322 HD patients were compared with 65 diabetes mellitus type 2 (DM) patients and 65 healthy controls. A questionnaire was held in regard to smoking habits and alcohol intake. Antibody levels against diphtheria were assessed by an in-house ELISA and a concentration of ≥0.1 IU/mL was regarded as protective. Effects of age, gender and time being on dialysis on protection were assessed by logistic regression. Ratios of individuals with protective antibody levels were found to be 36% (116/322), 27.7% (18/65), and 52.3% (34/65) for HD, DM, and control groups, respectively. Hemodialysis patients had a significantly (p < 0.05) lower protection rate than healthy controls. In all study groups, there was a tendency of higher protection rate with increasing age. These low ratios of protected individuals in both HD and DM patient groups are alarming, as these patients generally have defects in vaccine responses, and carriage is important in the perpetuation of diphtheria. The protection status of these patient groups might be improved with additional vaccinations.

Microbiologic Examination of Bandage Contact Lenses Used after Corneal Collagen Cross-linking Treatment

Abstract Purpose: To investigate the agents of bacterial contamination of contact lenses after corneal collagen cross-linking (CCL), and to present the possible changes of ocular flora after riboflavin/ultraviolet A. Methods: Seventy-two contact lenses of patients who underwent CCL and 41 contact lenses of patients who underwent photorefractive keratectomy (PRK) as control group were enrolled to the study. After 48 h of incubation, broth culture media was transferred to plates. Samples were accepted as positive if one or more colony-forming units were shown. Results: There were positive cultures in 12 (16.7%) contact lenses in the CCL group and 5 (12.2%) had positive cultures in PRK group. Coagulase-negative staphlycocci (CNS) were the most frequent microorganism. Alpha hemolytic streptococci and Diphteroid spp. were the other isolated microorganisms. Conclusions: Bacterial colonization can occur during and early after the CCL procedure in epithelial healing. To prevent corneal infections after the treatment, prophylactic antibiotics should be prescribed.

The in vitro effect of antimicrobial photodynamic therapy on Candida and Staphylococcus biofilms

Background/aim This study was designed to evaluate the effect of antimicrobial photodynamic treatment (APDT) in a biofilm model using combinations of various dyes (rose bengal, riboflavin, and methylene blue) as photosensitizers and light sources (LED and UVA) against staphylococcal and candidal biofilms. Materials and methods Sterile microtiter plates were used for the development and quantification of the biofilms. APDT was carried out using combinations of the light sources and dyes. The percentage of the growth inhibition was then calculated using a spectrophotometer. The broth media in the wells were aspirated, wells were stained with crystal violet, and optical density values were measured spectrophotometrically. SEM analysis of the impact of APDT on bacterial and fungal biofilms was also performed. Results The experiments showed that the most efficacious combination was red LED + methylene blue against both staphylococcal and candidal biofilms. A marked inhibition (45.4%) was detected on both C. albicans and C. parapsilosis biofilms. Red LED + methylene blue was also effective on S. aureus and S. epidermidis biofilms. SEM images suggested that the number of adherent cells and biofilm mass were markedly reduced after APDT treatment. Conclusion Although the results of this study indicated the in vitro efficacy of APDT, it might also be a promising technique for the control of biofilm growth within intravenous catheters.