Diagnostic ultrasound treatment increases the bone fracture-healing rate in an internally fixed rat femoral osteotomy model.

OBJECTIVE: To investigate the healing effects of diagnostic ultrasound in a standardized rat femur fracture model. METHODS: Thirty-two male rats aged 14 weeks were used, and each rat's right femur was osteotomized and stabilized under anesthesia. The rats were then divided into 4 groups. Five days after surgery, ultrasound was applied every fifth day with diagnostic sonographic equipment and a probe with a 7.5-MHz frequency and 11.8-mW/cm2 total output intensity for 10 minutes in each session. Ultrasound was applied 8 times in group A, 3 times in group B, and only once in group C. Ultrasound was not applied to sham-operated group D. Healing and callus formation of the rats' femur fractures were evaluated by radiography and dual-energy x-ray absorptiometry. RESULTS: Dual-energy x-ray absorptiometric and radiographic results showed that the ultrasound therapy accelerated the fracture healing. Radiographically, groups A and B showed better fracture healing than groups C and D. Ultrasound exposure increased both the whole-bone mineral density and the density at the fracture region, increasing in parallel with the exposure period. CONCLUSIONS: This study confirms the previously shown efficacy of low-intensity ultrasonic stimulation in acceleration of the normal fracture repair process even when performed with a diagnostic sonographic device.     

High frequency of aspirin resistance in patients with acute coronary syndrome

Aspirin is widely used for secondary prevention of cardiovascular disease, but is not effective for all patients. This phenomenon is called as aspirin resistance. Although the prognosis is worse in patients who develop acute coronary syndrome (ACS) while using aspirin, the frequency of aspirin resistance in these patients has not been evaluated. We aimed to evaluate the frequency of aspirin resistance in patients with ACS and to determine its relationship with the angiographic severity and extent of the associated coronary artery disease. The present study included 104 patients with ACS (75 men, 60.4 +/- 10.8 years) who were hospitalized while using aspirin for at least last 7 days and 100 patients with stable coronary artery disease (73 men, 57.6 +/- 10.6 years), documented by coronary angiography, history of revascularization or myocardial infarction (MI), and the use of aspirin for last 7 days. The latter group had no MI or ACS for last 3 months. Platelet function was assessed with PFA-100, which simulates primary homeostasis at injured blood vessels. Coronary angiography was performed in 83 cases of the patients with ACS during hospital stay. Aspirin resistance is more prevalent in patients with ACS (40.3%) when compared with stable coronary artery disease patients (27%). The difference was statistically significant (p = 0.04). The ACS patients with aspirin resistance were older and had severe myocardial damage. However, there were no significant differences in angiographic severity and extent of coronary artery disease between aspirin-resistant and aspirin-sensitive patients. Frequency of aspirin resistance is higher in patients who develop ACS while using aspirin than that in patients with stable coronary artery disease.     

Investigation of neuromuscular transmission in some rare types of migraine

The aim of this study was to delineate any dysfunction of neuromuscular transmission (NMT) by single-fibre electromyography (SFEMG) in some rare types of migraine. Recent studies have shown subclinical dysfunction of NMT in migraine with aura and cluster headache by using SFEMG, whereas another recent study has shown NMT to be normal in familial hemiplegic migraine (FHM) with CACNA1A mutations. Thirty patients with rare primary headache syndromes [18 with sporadic hemiplegic migraine (SHM), six with FHM and six with basilar-type migraine (BM)] and 15 healthy control subjects without any headache complaints underwent nerve conduction studies, EMG and SFEMG during voluntary contraction of the extensor digitorum communis muscle. Ten to 20 different potential pairs were recorded and individual jitter values calculated. The results obtained from patient groups were compared with those from the normal subjects. Of 600 individual jitter values of the patients, 27 (4.5%) were abnormally high, whereas only 3/205 (1.5%) jitter values from normal subjects were abnormal. Abnormal NMT was found in 4/30 (13.3%) patients (three SHM and one BM), but in none of the control subjects. Only in SHM patients was the number of individual abnormal jitter values slightly but significantly different from normal controls. The present study demonstrates that subclinical NMT abnormality is slightly present in only SHM and BM patients, but not in FHM patients.     

Intraductal growth-type mucin-producing peripheral cholangiocarcinoma associated with biliary papillomatosis

A 64-year-old woman with upper abdominal pain, nausea, and vomiting was admitted. The magnetic resonance imaging revealed marked dilation and "crowding" of the segment 4 bile ducts with an area suspicious for a stone or tumor. Ultrasonography-guided percutaneous transhepatic cholangiography revealed multiple filling defects in the segment 4 bile ducts, the left and common hepatic ducts. A left hepatectomy and cholecystectomy was performed. Dilated bile ducts containing mucinous material and a mass in the cystically dilated bile ducts of segment 4 were detected in the gross examination. It showed continuity within the surrounding dilated bile ducts. The dilated bile ducts of the segments 2 and 3 contained mucinous material without any apparent mass formation. Microscopically, the bile ducts were lined by biliary epithelium displaying simple and complex papillary structures with moderate to severe degree of dysplastic changes. The mass was composed of complex papillary structures filling the bile duct with a few foci of invasion. The papillary structures were composed of mucin-producing columnar cells as well as cells with oncocytic appearance. Patchy cytokeratin 7, cytokeratin 19, hepatocyte paraffin 1, MUC2, and CDX2 immunopositivities were observed. Biliary papillomatosis, mucin-producing intrahepatic cholangiocarcinoma, and intraductal papillary-type peripheral cholangiocarcinoma are in the same disease spectrum of papillary biliary neoplasm and termed as intraductal papillary neoplasm of the liver. Mucinous hypersecretion and signs of mucobilia are considered specific and should raise the suspicion of lesions in this spectrum.     

Biofilm formation by Staphylococcus epidermidis on nitrogen ion implanted CoCrMo alloy material

Staphylococcus epidermidis is the primary cause of medical device-related infections due to its adhesion and biofilm forming abilities on biomaterial surfaces. For this reason development of new materials and surfaces to prevent bacterial adhesion is inevitable. In this study, the adhesion of biofilm forming S. epidermidis strain YT-169a on nitrogen (N) ion implanted as well as on as-polished CoCrMo alloy materials were investigated. A medical grade CoCrMo alloy was ion implanted with 60 keV N ions to a high dose of 1.9 x 10(18) ions/cm(2) at substrate temperatures of 200 and 400 degrees C. The near-surface implanted layer crystal structures, implanted layer thicknesses, and roughnesses were characterized by XRD, SEM and AFM. The number of adherent bacteria on the surfaces of N implanted specimens was found to be 191 x 10(6) CFU/cm(2) for the 200 degrees C and 70 x 10(6) CFU/cm(2) for the 400 degrees C specimens compared to the as-polished specimen (3 x 10(6) CFU/cm(2)). The adhesion test results showed that S. epidermidis strain YT-169a adhere much more efficiently to the N implanted surfaces than to the as-polished CoCrMo alloy surface. This was attributed mainly to the rougher surfaces associated with the N implanted specimens in comparison with the relatively smooth surface of the as-polished specimen.     

Treatment with lithium, alone or in combination with olanzapine, relieves oxidative stress but increases atherogenic lipids in bipolar disorder

The changes in antioxidant-oxidant balance play important roles in the pathophysiology of neuropsychiatric conditions. Bipolar disorder (BD) is a psychiatric condition with recurrent mood disturbances. This study evaluates the effects of treatment with lithium, alone or in combination with antipsychotic olanzapine, on oxidant-antioxidant status and atherogenic character in patients with BD. The blood samples from 15 patients were tested before the treatment (pre-treatment phase) and at the ends of two consecutive treatment periods: period I, treatment with lithium and an antipsychotic drug, olanzapine (first 6 months) and period II, treatment with only lithium (6 months following period I). We measured serum atherogenic lipids (total cholesterol, triglycerides, and LDL-cholesterol), plasma lipid peroxides (thiobarbituric acid-reactive substances), antioxidant enzymes (glutathione peroxidase, superoxide dismutase, and catalase) in neutrophils and lymphocytes, and total antioxidant status in plasma. Compared with pre-treatment phase, the lipid parameters were increased with each treatment; especially, LDL-cholesterol was significantly increased only with lithium treatment. These findings alert to be cautious about use of lithium in patients with atherogenic conditions. Moreover, plasma lipid peroxides were decreased significantly after the combination therapy and further decreased with lithium treatment. Antioxidant enzyme activities in lymphocytes were decreased after both types of treatment. Importantly, plasma total antioxidant status was increased only with lithium treatment. Thus, treatment with lithium alone decreases already up-set oxidant status in BD. In conclusion, the combination therapy with olanzapine is better in terms of atherogenic profile, while lithium alone produces better antioxidant status in patients with BD.     

Localization of the marginal mandibular branch of the facial nerve

The aim of this study was to observe the course of the marginal mandibular branch of the facial nerve (MMBFN) in relation to the inferior border of the mandible and parotid gland and its relevance to surgical procedures such as rhytidectomy and parotid gland surgery. In this study, 50 specimens were dissected. The relationships between the MMBFN and the inferior border of the mandible were recorded and analyzed. We found that posterior to the facial artery, the MMBFN ran above the inferior border of the mandible in 37 (74%) of the specimens. In 11 (22%) specimens, below the inferior border of the mandible it was divided into two branches at the crossing point with the facial artery. In 2 (4%) specimens the MMBFN divided into two branches at the point of emergence from the parotid gland. There were no statistical differences between the left and right sides, and both sexes. The MMBFN is one of the most vulnerable branches to surgical injury because of its location. For this reason, the surgeons who are willing to operate on this area, especially for the rhytidectomies, should have a true knowledge about the anatomy of this branch.     

Color change evaluation of denture soft lining materials in coffee and tea

This study evaluated the color stability of soft denture liners after being exposed to coffee and tea solutions for different time periods. Four soft denture liners and a denture base polymer were tested. Five specimens of each material were immersed in either coffee or tea solution at 50 +/- 1 degrees C for one, three, nine, 24, 48, and 96 hours. Color measurements were made using a reflectance spectrophotometer before and after the specimens were exposed to the solutions. After 96 hours' immersion in coffee and tea solutions, coffee produced more marked color changes than did tea for all the materials tested. Surface roughness (Ra) of the materials after being cured against a stainless steel surface was also measured with a contact-type surface roughness measuring instrument. Due to the different surface structures, which thus accounted for the different Ra values, the materials behaved differently when immersed in different solutions.     

Conjunctival flora in patients with type 1 or type 2 diabetes mellitus

Patients with diabetes mellitus (DM) are prone to infection because glucose in the skin, urine, mucous membranes, and tears promotes growth of microorganisms. Conjunctival flora develops soon after birth, and some saprophytic conjunctival flora play a pathogenic role when immune function is compromised, which can lead to serious infection. DM is one condition that may compromise immune status. In lacrimal function tests of DM patients, a decrease in breakup time (BUT) of lacrimal film and a decrease in Schirmer’s test results were seen. In the present study, conjunctival flora in patients with DM was compared with that in controls with regard to type and duration of diabetes and results of lacrimal function tests. Seventeen patients with type 1 DM (n=34 eyes), 66 patients with type 2 DM (n=132 eyes), and 50 control subjects (n=100 eyes) were included. The control group consisted of age-matched patients with no ophthalmologic problems other than refractive error. Clycosylated hemoglobin values were measured with highpressure liquid chromatography with the Hi-AUTOA1c analyzer (Kyoto Daiichi Kagatu Co., Ltd., Kyoto, Japan). Type and duration of diabetes and demographic data were recorded, and routine ophthalmologic examinations were performed; the BUT of lacrimal film was determined, and the results of Schirmer’s test were assessed. Microbiologic sampling was performed twice for both eyes with sterile cotton swabs. One sample was incubated in 2 mL of brain-heart infusion broth agar; the other was incubated for the presence of fungi in Sabouraud dextrose agar. Colony morphology, hemolysis, and Cram’s stain, as well as catalase, oxidase, and coagulase tests were performed. No growth was observed in 12 of 1 7 patients (35.4%) with type 1 DM, 28 of 66 patients (21.2%) with type 2 DM, and 25 of 50 control subjects (50%).Staphylococcus epidermidis (11.79%) andStaphylococcus aureus (11.7%) were the most frequently isolated organisms in the type 1 DM group, and Sepidermidis (24.2%) and Saureus (21.2%) were the predominant organisms in the type 2 DM group. In control subjects, Sepidermidis (22%), Saureus (12%), andCorynebacterium spp (10%) were the most frequently isolated organisms, and the number of eyes with growth of Saureus was significantly higher in the type 2 DM group than in the other groups (P<.01). Patients with diabetes are more prone to postoperative endophthalmitis than are nondiabetics, and preoperative application of antiseptic or antimicrobial agents to the conjunctiva may not sterilize the area. Impaired integrity of the posterior capsule may also increase the risk of endophthalmitis. Postoperative endophthalmitis is usually associated with gram-positive organisms (75%–80%); gram-negative organisms (15%–29%) and fungi (3%–13%) account for a smaller number of cases. A high rate of resistance to penicillin, ampicillin, and tetracycline was observed in Saureus isolates, although resistance to vancomycin was absent, rendering this molecule the most effective therapeutic option. In this study, Sepidermidis and Saureus were the 2 most frequently isolated organisms in patients with DM. It is concluded that the conjunctival flora in diabetic subjects differs from that in nondiabetic subjects. This should be considered preoperatively and postoperatively, and prophylactic and postoperative treatment should be administered accordingly to diabetic patients.     

Who Is the Preferred Tutor in Clinical Skills Training: Physicians,Nurses, or Peers?

Phenomenon: Clinical skills centers allow structured training of undergraduate medical students for the acquisition of clinical skills in a simulated environment. Physician, nurse, or peer tutors are employed for training in those centers. All tutors should have appropriate training about the methodology used in the clinical skills training. Many of the studies revealed the effectiveness of various types of tutors. The aim of our study was to evaluate medical students' satisfaction with clinical skills training, and their opinions about the differences in coaching skills among the physician, nurse, and peer tutors. Approach: This study was conducted with third-year students (467 students) in 2013-2014 academic year at Hacettepe University Faculty of Medicine. Participation rate was 85 % (397 students). The students attended the suturing skill training in groups of 40 students. First, a faculty member from the Department of Medical Education delivered a video demonstration and conducted discussion. After the demonstration, the students were divided into groups of 5-6 students. A physician, nurse, or a peer tutor facilitated each group. The students were asked to complete the Coaching Skills Evaluation Form after the practicum session. It contained 13 criteria for assessing the coaching skills. Additionally, the form included a question for rating the student's satisfaction with the tutor. The performance of the tutors at each step was rated on a three-point scale. Findings: Kruskal Wallis analysis was used to compare students' scores for their tutors. The students' satisfaction with tutors was high for all of the tutors. However, there was no difference between students' scores in suturing skill, and between physician, nurse, and peer tutors' coaching skills. Insights: In this study, we revealed that physician, nurse, and peer tutors were equally effective on the students' performances. They were also regarded as effective in their teaching role by students. But the most important point was that sufficient tutor training and preparation was crucial for the success of models.