The effect of mucine, IgA, urea, and lysozyme on the corrosion behavior of various non-precious dental alloys and pure titanium in artificial saliva

The corrosion of dental alloys has biological, functional, and aesthetic consequences. Various studies have shown that protein solutions can inhibit the corrosion of alloys. This study is planned to determine the relationship of organic constituents of saliva and the corrosion of dental alloys. The organic constituents are IgA, mucine, urea, and lysozyme which are encountered in the highest amounts in saliva and the dental materials are titanium (Ti), Co-Cr-Mo and Ni-Cr-Mo alloys, and dental amalgam, the most often used metallic components in dentistry. In particular, the interactions between the commonest salivary proteins, IgA, mucine, urea and lysozyme, and Ti, Co-Cr-Mo, Ni-Cr-Mo and dental amalgam were investigated. Each alloy was evaluated by cyclic polarization in each medium. The general anodic and cathodic behavior during forward and reverse cycles, the corrosion and passivation current densities (muA/cm2 ), and the corrosion and the pitting potentials (mV) were determined. The results have shown that Ni-Cr-Mo and dental amalgam alloys are highly susceptible to corrosion in all the investigated media. The Co-Cr-Mo alloy has shown high passive current densities in the solution of mucine and lysozyme in artificial saliva. Titanium instead, has shown a high resistance to corrosion and a stable passive behavior in all media, especially in a solution of mucine and IgA in synthetic saliva. Mucine and IgA, as well as urea and lysozyme, appeared to enhance the formation of a passive film layer on the Ti metal surface, thus inhibiting the corrosion. Based on the study findings, and especially considering the problem of nickel allergy and toxicity of mercury released from dental amalgam, the use of Co-Cr-Mo alloys and Ti to Ni-Cr-Mo alloys is recommended and alternatives to dental amalgam should be sought for patients with impaired salivary flow.     

Effects of N-acetylcysteine on pulmonary function in patients undergoing coronary artery bypass surgery with cardiopulmonary bypass

Cardiopulmonary bypass (CPB) has been implicated in causing poor pulmonary gas exchange postoperatively in patients undergoing coronary artery bypass grafting (CABG) procedures. In this prospective, randomized, double-blind, placebo-controlled study, we examined the pulmonary effects of N-acetylcysteine (NAC) in patients undergoing CABG. Twenty patients undergoing elective CABG and early tracheal extubation were randomized into two groups. Group I (ten patients) received a physiologic salt solution as a placebo in a continuous intravenous infusion for one hour before CPB and 24 hours after CPB; Group II (ten patients) received 100 mg/ kg NAC intravenously for one hour before CPB and 40 mg/kg/day at 24 hours after CPB. Perioperative hemodynamic and pulmonary data were recorded. Postoperative tracheal extubation was accomplished at the earliest appropriate time. The postoperative clinical course was similar in the two groups. Both groups exhibited significant postoperative increases in A-a oxygen gradient (p < 0.01), but patients in Group II exhibited significantly lower increases in postoperative A-a oxygen gradient (p < 0.006). Other hemodynamic and pulmonary data (pulmonary capillary wedge pressure, pulmonary vascular resistance (PVR), cardiac index (CI), shunt flow, dynamic lung compliance and static lung compliance) exhibited no differences between the groups. There was no significant difference in terms of intubation time. The malondialdehyde (MDA) increase in Group II following CPB was found to be significantly lower than in Group I (p = 0.043). This clinical study reveals that administration of NAC to patients undergoing elective CABG with CPB improves systemic oxygenation. There was no effect in other pulmonary parameters and in terms of intubation time.     

Plasma leptin concentrations in postmenopausal women with osteoporosis

BACKGROUND: The obese are usually protected against osteoporosis and have increased bone mineral density and plasma leptin concentrations. A recent in vitro study demonstrated that leptin acts on human marrow stromal cells to enhance differentiation to osteoblasts, suggesting an influence of leptin on bone mass. However, little is known about the relationship between plasma leptin and bone mass in postmenopausal women with osteoporosis. OBJECTIVE: To investigate plasma leptin concentrations in postmenopausal women with osteoporosis to improve the understanding of the role of leptin in determining bone mass. METHODS: Fifty postmenopausal women with osteoporosis (ages 61.18+/-6.51 years; body mass index (BMI) 28. 91+/-3.44kg/m(2), mean+/-s.d.) and 30 age- and BMI-matched healthy postmenopausal women were included in the study. Bone mineral densities (BMD) were measured by dual energy X-ray absorptiometry. Plasma leptin concentrations were determined using an immunoradiometric assay. RESULTS: The median spine BMD value in the patient group (0.695+/-8.26g/cm(2), median+/-s.e.m.) was significantly lower than that in the control group (1.006+/-1. 29g/cm(2), median+/-s.e.m.; z=-7.454, P<0.001). The median plasma leptin concentration in the patient group (18.70+/-1.78ng/ml, median+/-s.e.m.) was not significantly different from that in the control group (22.35+/-2.20ng/ml, median+/-s.e.m.; z=-1.630, P=0. 103). Plasma leptin concentrations were correlated with BMI in both groups (r(s)=0.394, P=0.031 in controls and r(s)=0.404, P=0.004 in the patient group). There was no correlation between plasma leptin concentrations and BMD values in controls (r(s)=-0.107, P=0.575) but a weak correlation was observed in the patient group (r(s)=0.285, P=0.045). CONCLUSION: Our data suggest that circulating plasma leptin does not have a significant direct influence on bone mass in postmenopausal women.     

Open fixation in flail chest: review of 64 patients

The strategy for treatment of flail chest remains controversial. Various alternatives were assessed by reviewing the records of 64 patients treated from 1991 through 2000. Patients were classified according to therapeutic approach: group 1 was 27 patients who underwent open fixation of the fractured ribs, group 2 was 19 patients managed by intermittent positive-pressure ventilation, and group 3 was 18 patients managed mainly by synchronized intermittent mandatory ventilation. Two patients initially treated by ventilation underwent successful open fixation. In group 1, ventilatory support was required in 21 (77.8%) patients postoperatively, the mean duration of ventilation was 3.1 days, mean hospital stay was 18.3 days, morbidity was 11.1% (3/27), and mortality was 11.1%. In groups 2 and 3, the mean time for stabilization of paradoxical chest wall movement was 6.6 days, and mean duration of ventilation was 7.2 days. Mortality was 27.0% (10/37) in patients treated nonsurgically; 21.0% (4/19) in group 2, and 33.3% (6/18) in group 3. In groups 2 and 3, pain control required epidural analgesia in 13 (35.1%) cases, intercostal nerve blockade in 16 (43.2%), and narcotic or nonnarcotic parenteral analgesia in 8 (21.6%). Open fixation is a successful treatment modality for traumatic flail chest.     

Frailty prevalence and related factors in the older adult—FrailTURK Project

Frailty is one of the geriatric syndromes and has an important relationship with mortality and morbidity. The aim of this study is to present the characteristics, prevalence, and related factors of frailty in older adults in our country. The study included 1126 individuals over 65 years of age from 13 centers. Frailty was evaluated using the Fried Frailty criteria, and patients were grouped as “frail,” “pre-frail,” and “non-frail.” Nutritional status was assessed with “Mini Nutritional Test,” psychological status with the “Center for Epidemiological Studies Depression Scale-CES-D,” and additional diseases with the “Charlson Comorbidity index.” Approximately 66.5 % of the participants were between 65 and 74 years of age and 65.7 % were women. Some 39.2 and 43.3 % of the participants were rated as frail and pre-frail, respectively. The multinomial logistic regression analysis was used to determine the factors associated with frailty. It was observed that age, female gender, low education level, being a housewife, living with the family, being sedentary, presence of an additional disease, using 4 or more drugs/day, avoiding to go outside, at least one visit to any emergency department within the past year, hospitalization within the past year, non-functional ambulation, and malnutrition increased the risk of frailty (p < 0.05). Establishing the factors associated with frailty is highly important for both clinical practice and national economy. This is the first study on this subject in our country and will provide guidance in determining treatment strategies.     

Parathyroid adenoma screening efficacies of different imaging tools and factors affecting the success rates

PurposeWe aimed to compare the efficacy of three different parathyroid adenoma screening tools—high-resolution ultrasonography (USG), technetium Tc 99m-methoxyisobutylisonitrile (MIBI) parathyroid scintigraphy, and magnetic resonance imaging (MRI)—and we evaluated the factors affecting the detection success rates.MethodsParathyroid imaging was evaluated by USG, double-phase 99mTc-MIBI parathyroid scintigraphy, and cervical MRI in patients with hyperparathyroidism (n=39).ResultsAmong the 39 patients, USG, parathyroid scintigraphy, and MRI correctly identified 35 adenomas (89.7%), 28 adenomas (71.8%), and 26 adenomas (66.7%), respectively. Positive predictive values for USG (34/35), scintigraphy (27/28), and cervical MR (26/26) imaging were 97.1%, 96%, and 100%, respectively. Parathyroid adenomas were detected with 92.3% (36/39) certainty when both USG and scintigraphy modalities were applied together. Minimally invasive parathyroidectomy under local anesthesia with unilateral incision was successfully performed in 24 (61.5%) patients.ConclusionsMinimally invasive surgery for parathyroid adenomas has been developed and has equal success with traditional surgery. However, accurate localization of adenomas should be obtained prior to surgery. In this study, ultrasound was found to be effective in localizing adenomas for successful surgery. Adding other imaging modalities does not improve localizing the parathyroid adenomas.     

Endobronchial findings of hydatid cyst disease: a report of five pediatric cases

Hydatid disease is still an important public health problem throughout the world. Diagnosis of the disease is generally based on clinical and radiological findings. Evaluation of pulmonary disorders by flexible bronchoscopy (FOB) is a rapidly developing facility, but diagnostic and therapeutic FOB for pulmonary hydatid cysts is still controversial. This study examines the findings of endobronchial hydatid cyst disease in five pediatric patients from Turkey, and clinical experience about this subject is reviewed. All our patients presented with unusual symptoms of the disease, and for all of them, diagnosis had been delayed using current diagnostic methods. As a result of our experience, it can be reported that the endobronchial appearance of the hydatid cyst membrane is whitish-yellow, and it is difficult to differentiate it radiologically from some other common causes of endobronchial lesions in childhood, such as endobronchial tuberculosis, foreign body aspirations, mucous plaques, and granulation scars. The findings of these cases show that, hydatid cyst should also be kept in mind in differential diagnosis of endobronchial lesions. In the diagnosis of pulmonary hydatid cyst in children without typical clinical and radiological findings of the disease, FOB examination is a valuable diagnostic procedure.