Evaluation of different strategies to promote a protective immune response against leptospirosis using a recombinant LigA and LigB chimera

Leptospirosis is a zoonosis of worldwide distribution, caused by infection with pathogenic Leptospira species. The vaccines that are currently available are bacterins, with limited human use, that confer short-term, serovar-specific immunity. Lig proteins are considered to be the best vaccine candidates to date. Here, we aimed to construct a recombinant Lig chimera (LC) comprised of LigAni and LigBrep fragments, and to evaluate it as subunit or DNA vaccine using different administration strategies. Vaccines were formulated with 50?µg of recombinant LC associated with different adjuvants or with 100?µg of pTARGET/LC. Four-week-old hamsters received two doses of vaccine with different strategies and were challenged with 5?×?DL₅₀ Leptospira interrogans serovar Copenhageni strain Fiocruz L1-130. The immune response generated by Lig chimera conferred 100% protection to hamsters treated with at least one dose of recombinant LC. Despite the high levels of antibodies that vaccinated animals produced, a sterilizing immunity was not achieved. The lack of a sterilizing immunity could indicate the importance of a mixed humoral and cellular immune response. The present study generated insights that will be useful in the future development of improved subunit vaccines against leptospirosis.     

Knowledge and awareness about diabetes and periodontal health among Jordanians

The aim of this study is to evaluate the awareness, perception, sources of information, and knowledge of diabetes mellitus and periodontal health among Jordanians, to examine the factors related to their knowledge, and organize effective education programs. A random sample of 500 diabetic patients was recruited from three hospitals and three comprehensive health centers that represent both urban and rural populations in Jordan between September 25, 2006, and February 20, 2007. Completed questionnaires with the answers were returned by 405 participants (response rate was 81%). Only 28% indicated that they followed up gum diseases with the dentist; 48% were aware that diabetic patients are more prone to gum diseases and oral health complications. About a third (38%) recognized that their periodontal health might affect their glycaemic level. Television and Internet were the main source of knowledge for dentists with the rate of 50%. Knowledge about diabetes and periodontal health among diabetic patients is low, and majority of patients were unaware of the oral health complications of their disease and the need for proper preventive care. Issues on education need to be addressed. Therefore, appropriate educational programs should be planned according to community needs, and the target of these programs should be patients with irregular visits to the dentist and physicians. The clinical implication of our findings is that dentists, physicians, and other health providers should inspect diabetic patients for gum diseases each time they come for care and recommend that diabetic patient see a dentist regularly.     

Factors associated with poor glycemic control among patients with Type 2 diabetes

ObjectivesDetermine factors associated with poor glycemic control among Jordanian patients with Type 2 diabetes.MethodsA systematic random sample of 917 patients was selected from all patients with Type 2 diabetes over a period of 6 months in 2008. A prestructured questionnaire sought information about sociodemographic, clinical characteristics, self-care management behaviours, medication adherence, barriers to adherence, and attitude towards diabetes. Weight, height, and waist circumferences were measured. All available last readings of hemoglobin A1c (HbA1c), fasting blood sugar measurements and lipid were abstracted from patients' records. Poor glycemic control was defined as HbA1c ≥7%.ResultsOf the total 917 patients, 65.1% had HbA1c ≥7%. In the multivariate analysis, increased duration of diabetes (>7 years vs. ≤7years) (OR=1.99, P≤.0005), not following eating plan as recommended by dietitians (OR=2.98, P≤.0005), negative attitude towards diabetes, and increased barriers to adherence scale scores were significantly associated with increased odds of poor glycemic control.ConclusionThe proportion of patients with poor glycemic control was high, which was nearly comparable to that reported from many countries. Longer duration of diabetes and not adherent to diabetes self-care management behaviors were associated with poor glycemic control. An educational program that emphasizes lifestyle modification with importance of adherence to treatment regimen would be of great benefit in glycemic control.     

Effect of low-intensity pulsed ultrasound on fracture callus mineral density and flexural strength in rabbit tibial fresh fracture

Background  

Low-intensity ultrasound is a biophysical intervention on a fracture repair process. However, the effect of low-intensity ultrasound therapy on fracture healing is controversial. The aim of the present study was to evaluate the effect of low-intensity pulsed ultrasound (LIPUS) therapy on the fracture healing process, including mineral density and strength of callus using a rabbit model.     

Epidemiology of bacteraemia in Hamad general hospital, Qatar: a one year hospital-based study

We conducted a one-year observational study from July 2007 to June 2008 to describe the epidemiology of bacteraemia at Hamad general hospital. During this period, a total of 452 episodes of bacteraemia occurred, which corresponds to a rate of 19/1000 hospital admissions. Most patients 58.8% (266/452) had community acquired bacteraemia, and primary bacteraemia accounted for 62.2% (281/452) of the cases. The most common source of bacteraemia was intravenous catheterization in 19.2% (87/452) but no source was identified in 42.9% (194/452) of the episodes. Gram-negative organisms were isolated in 63.1% (285/452) episodes with Escherichia coli being the most frequent 21.5% (97/452). Multidrug resistance was observed in 33.3% (7/21) of all Pseudomonas aeruginosa isolates, 50% (6/12) of Acinetobacter isolates and 28.6% (6/21) of Enterobacter isolates, whereas all ESBL producing Klebsiella spp. and E. coli were multiresistant. The percentages of oxacillin resistant coagulase negative Staphylococci isolates and methicillin-resistant Staphylococcus aureus isolates were 81.8% (27/33) and 13.2% (7/53) respectively. In hospital mortality was 22.5% (102/452), and inadequate treatment and septic shock were found to be independent predictors of mortality. Therefore, bloodstream infection surveillance is crucial to produce meaningful guidelines for prevention (e.g., catheter-related) and empirical treatment of bacteraemia in Qatar.     

Cholestasis induces apoptosis in mice cardiac cells: the possible role of nitric oxide and oxidative stress

Background/Aims: Acute cholestasis is associated with cardiovascular complications. The purpose of the present study was to investigate the effect of cholestasis on heart apoptosis and the involvement of nitric oxide (NO) and oxidative stress in the possible altered apoptosis of cholestatic hearts. Methods: Cholestasis was induced by bile duct–ligation, and sham‐operated mice served as controls. Three days after the surgery, heart tissues were evaluated for apoptosis and the level of malondialdehyde (MDA), and the activities of catalase (CAT), glutathione peroxidase (GSHPx) and superoxide dismutase (SOD) have been studied in cardiac tissues. The role of treatment with l ‐NAME, a non‐selective inhibitor of NO synthase, or with d ‐NAME, an inactive isomer of l ‐NAME, on cholestatic and sham cardiac apoptosis, level of MDA and CAT, SOD and GSHPx activities was also investigated. The content of NO in cardiac tissue was also determined. Results: Cholestatic hearts showed structural abnormalities and increased apoptosis compared with sham hearts. Treatment with l ‐NAME, but not d ‐NAME, improved both structural abnormalities and enhanced apoptosis of cholestatic hearts. Cholestatic hearts also had an increased level of MDA and decreased activities of CAT and GSHPx, which were not modified by d ‐NAME treatment. By l ‐NAME treatment, the level of MDA decreased and activities of CAT, GSHPx and SOD increased in BDL mice. The content of NO was higher in cholestatic cardiac tissue, which was decreased by l ‐NAME treatment. Conclusion: In conclusion, apoptosis in cholestatic heart might have occurred because of NO overproduction, which could induce oxidative stress in the heart of cholestatic mice.     

Propolis protects against 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced toxicity in rat hepatocytes

The present experiment was undertaken to determine the effectiveness of propolis in alleviating the toxicity of TCDD on cultured primary rat hepatocytes. Propolis (25, 50 and 100 μM) was added to plain culture or simultaneously with TCDD (5 and 10 μM). The hepatocytes were treated with TCDD and propolis for 48 h. Then cell viability was detected by [3-(4,5-dimethyl-thiazol-2-yl) 2,5-diphenyltetrazolium bromide] (MTT) assay and lactate dehydrogenase (LDH) release, while total antioxidant capacity (TAC) and total oxidative stress (TOS) levels were determined to evaluate the oxidative injury. The DNA damage was also analyzed by liver micronucleus assay (LMN) and 8-oxo-2-deoxyguanosine (8-OH-dG). The results of MTT and LDH assays showed that TCDD decreased cell viability. TCDD also increased TOS level and decreased TAC level in rat hepatocytes. On the basis of increasing doses, the TCDD caused significant increases of micronucleated hepatocytes (MNHEPs) and 8-OH-dG levels as compared to control culture. In cultures treated with propolis alone, cell viability and TOS level were not affected, while the level of TAC was significantly increased in dose-dependent fashion. The presence of propolis with TCDD modulated its toxic effects on primary hepatocytes cultures. Noteworthy, propolis has a protective effect against TCDD-mediated DNA damages.