Erbium, chromium:Yttrium-scandium-gallium-garnet (Er, Cr:YSGG) laser versus diode laser in the treatment of pericoronitis.

Background: There are limited number of studies about the lasers used for the treatment of pericoronitis infection. Aim: To compare the Er, Cr:YSGG laser and diode laser applications clinically in the treatment of pericoronitis infection. Patients and Methods: Sixty patients with pericoronitis infection were divided into three groups using block randomization: Er, Cr:YSGG + antibiotic group, n = 20 (mean age: 24.20 ± 6.13; 14 females, 6 males); diode group + antibiotic, n = 20 (mean age: 23.45 ± 2.96; 14 females, 6 males); and antibiotic, n = 20 (mean age: 22.45 ± 3.02; 11 females, 9 males). In addition, laser application was performed for patients in the Er, Cr:YSGG and diode laser groups on the 1st and 2nd days until the extraction day. Tooth extractions were performed on the 3rd day for all patients. Patients' pain (with visual analog scale [VAS]), lymphadenopathy, and local edema were clinically evaluated in the first 3 days and on the 7th day of treatment. Results: Pain score on the 2nd day of treatment was determined to be significantly lower in the Er, Cr:YSGG + antibiotic laser group as compared with the other two groups (P = 0.019). Although regression of lymphadenopathy on the 3rd day was highest (P = 0.025) in the Er, Cr:YSGG group, there was no significant difference between the groups regarding local edema. Conclusion: Er, Cr:YSGG laser improved the healing process in the treatment of pericoronitis and made an important contribution to the treatment.

Factors affecting anxiety-fear of surgical procedures in dentistry.

AIM: To compare dental anxiety and fear during procedures performed under local anesthesia either in the operating room or in the clinic as well as to investigate the potential factors that might influence this psychological condition. SUBJECTS AND METHODS: Patients who were admitted to the Department of Oral and Maxillofacial Surgery of the universities in two cities, which have a different sociocultural patient profile, were enrolled. In addition to the State-Trait Anxiety Inventory (STAI), Dental Anxiety Scale (DAS), and Dental Fear Scale (DFS), the patients were asked to answer the questions concerning previous dental experience, education level, and previous psychiatric therapy. STATISTICAL ANALYSIS USED: The results of STAI were analyzed by Mann-Whitney U-test and results of DAS and DFS were analyzed by one-way analysis of variance test. RESULTS: Two hundred patients, of whom 76 were enrolled in the first center and 124 were enrolled in the second center. A statistically significant difference was observed in state anxiety levels of the patients between the two centers, whereas the difference in trait anxiety levels was not significant. The results of DAS, DFS, and STAI-trait (STAI-T) displayed a significant difference between genders; the levels of anxiety and fear were higher in females than in males (DAS P = 0.025, DFS P = 0.017, STAI-T P = 0.045). Comparison between the patients with and without previous dental experience revealed a statistically significant difference regarding the results of STAI. CONCLUSIONS: The study found that sociocultural structure and gender are the significantly effective factors on dental anxiety and fear.

Prognostic analysis of patients with operable gastric cancer and tolerability to adjuvant radio-chemo-therapy.

The aim of this study is to evaluate the tolerability and toxicity of adjuvant chemoradiotherapy (CRT) and to analyze the prognosis in patients with operable gastric cancer. The retrospective analysis included 723 patients with operable gastric cancer; stage IB-IV (M0), received adjuvant CRT from 8 Medical Centers in Turkey between 2003 and 2010. The patients' age, sex, tumor localization, Lauren classification, grade and stage of the disease, type of dissection, the toxicity and tolerability status and survival rate were analyzed. All patients were divided into two groups as tolerable group to adjuvant CRT and intolerable group to adjuvant CRT .Among the patient, 73.9% had stage III-IVM0 disease; 61.0% had the intestinal type of gastric cancer, 51.1% had the distal type, and 61.4% had undergone D2 dissections. The number of patients who completed the entire course of the adjuvant CRT was 545 (75.4%).The median follow-up period was 20.8 months (range: 1.5-107 months). Overall Survival (OS) rates were 80% and 52%, while the relapse free survival (RFS) rates were 75% and 48% at 1 and 3 years, respectively.In the univariate analysis of the groups based on the the age defined as <65 or ≥ 65 (p=0.16 / p=0.003), Lauren classification (p=0.004 / p<0.001), localization of tumor (p=0.02 / p=0.04), tumor grade (p=0.06 / p=0.003), disease stage (p<0.001 / p<0.001), type of dissection (p=0.445 / p=0.043), presence or absence of toxicity (p=0.062 / p=0.077) and tolerability of the therapy (p=0.002 / p=0.001). In the cox regression analysis, tumor stage (Hazard Ratio (HR): 0.332; 95% confidence interval (CI): 0.195-0.566; p<0.001), and tolerability (HR: 0.516; 95% CI: 0.305-0.872; p=0.014), were found to be related with the OS. Tumor stage (HR: 0.318; 95% CI: 0.190-0.533; p=<0.001) and tolerability (HR: 0.604; 95% CI: 0.367-0.995; p=0.048) were observed to be statistically significant in terms of the RFS.We have observed that whether a patient can or cannot tolerate adjuvant CRT due to its toxicity is an independent prognostic factor besides the known prognostic factors like tumor stage and Lauren classification. We are of the opinion that the treatment of patients who cannot tolerate adjuvant CRT should be replaced with less toxic adjuvant therapies.

The effect of being overweight on survival in patients with gastric cancer undergoing adjuvant chemoradiotherapy.

The aim of this study was to examine the effect of being overweight on survival in patients with gastric cancer undergoing adjuvant chemoradiotherapy and chemotherapy. In this study 152 patients were evaluated. Radiotherapy dose was 45 Gy given in 5 weeks. 5-FU 425 mg/m(2) and folinic acid 20 mg/m(2) were administered weekly during the radiotherapy and four cycles with 4-week intervals as consolidation chemotherapy after radiotherapy. Patients were assigned into two groups according to their body mass index: overweight (body mass index ≥25 kg/m(2)) and normal weight (body mass index <25.0 kg/m(2)). The median overall survival was 39 months vs. 18 months and median disease-free survival was 27 months vs. 13 months in the overweight and normal-weight groups respectively (P = 0.004 and P = 0.006 respectively). The 5-year survival was better in the patients with overweight than those with normal weight (42% vs. 17%; P = 0.004). The overall survival was significantly better with being overweight and early pathological stage (P = 0.016 and P = 0001 respectively). Overall survival, disease-free survival and long-term survival in patients with gastric cancer undergoing adjuvant treatment were better in overweight than normal-weight patients. Moreover, it was shown that body mass index and pathological stage were associated to survival and prognosis.

Oscillatory Activities in Multiple Frequency Bands in Patients with Schizophrenia During Motion Perception.

Patients with schizophrenia show impairment in binding stimulus features into coherent objects, which are reflected in disturbed oscillatory activities. This study aimed to identify disturbances in multiple oscillatory bands during perceptual organization of motion perception in patients with schizophrenia. EEG was recorded from healthy controls and patients with schizophrenia during continuous presentation of a motion stimulus which induces reversals between two exogenously generated perceptions. This stimulus was used to investigate differences in motion binding processes between healthy controls and patients with schizophrenia. EEG signals were transformed into frequency components by means of the Morlet wavelet transformation in order to analyse inter-trial coherences (ITC) in the delta (1-4 Hz), theta (4-7 Hz), alpha (8-12 Hz), and gamma (28-48 Hz) frequency bands during exogenous motion binding. Patients showed decreased delta-ITC in occipital and theta-ITC in central and parietal areas, while no significant differences were found for neither alpha nor gamma-ITCs. The present study provides one of the first insights on the oscillatory synchronizations related with the motion perception in schizophrenia. The ITC differences revealed alterations in the consistency of large-scale integration and transfer functions in patients with schizophrenia.

Arbuscular mycorrhiza influences carbon-use efficiency and grain yield of wheat grown under pre- and post-anthesis salinity stress.

Soil salinity severely affects and constrains crop production worldwide. Salinity causes osmotic and ionic stress, inhibiting gas exchange and photosynthesis, ultimately impairing plant growth and development. Arbuscular mycorrhiza (AM) have been shown to maintain light and carbon use efficiency under stress, possibly providing a tool to improve salinity tolerance of the host plants. Thus, it was hypothesized that AM will contribute to improved growth and yield under stress conditions. Wheat plants (Triticum aestivum L.) were grown with (AMF+) or without (AMF-) arbuscular mycorrhizal fungi (AMF) inoculation. Plants were subjected to salinity stress (200 mm NaCl) either at pre- or post-anthesis or at both stages. Growth and yield components, leaf chlorophyll content as well as gas exchange parameters and AMF colonization were analysed. AM plants exhibited a higher rate of net photosynthesis and stomatal conductance and lower intrinsic water use efficiency. Furthermore, AM wheat plants subjected to salinity stress at both pre-anthesis and post-anthesis maintained higher grain yield than non-AM salinity-stressed plants. These results suggest that AMF inoculation mitigates the negative effects of salinity stress by influencing carbon use efficiency and maintaining higher grain yield under stress.

Altered oscillatory alpha and theta networks in schizophrenia.

In the present study we used a simple visual evoked potential and a visual oddball paradigm to investigate alterations in the temporal integration of different frequency components such as alpha and theta oscillations in patients with schizophrenia. We found that neither the amplitude enhancement after stimulus onset nor the intertrial phase coherence was generally reduced in patients, but that the topography of the neural response was altered. While healthy controls elicited their maximum early alpha as well as late theta response over posterior electrode sites, the maximum response in patients was shifted to anterior electrode positions. This result was not found for the late theta response for targets as target processing was accompanied with frontal theta amplitude enhancement in healthy controls as well. The change of the topographical response pattern was mirrored by the intertrial phase coherence in both frequency bands. The findings imply that schizophrenia is related to multiple alterations in oscillatory networks. Even during simple tasks without high cognitive demands dysfunctional mechanisms of temporal and regional coordination appear to be of importance in schizophrenia.

Local differences in the position of the mental foramen.

The mental foramen has been reported to vary in position in different ethnic groups. Repeated failures during injections and operative procedures involving the mental foramen suggest the presence of local differences in a given population. The aim of the present study was to investigate possible local differences of the mental foramen in Eastern Anatolian individuals in the Turkish population. The present investigation is based on the examination of 70 adult mandibles. The study consisted of three measurements, to include the relations of the mental foramen to the following: 1) the lower teeth; 2) the body of mandible; 3) the mandibular symphysis and posterior border of the ramus of the mandible. The most common position of the foramen was in line with the longitudinal axis of the second premolar tooth (relation IV), at the midpoint of the mandibular body height and at 1/3.5 of the distance from the mandibular symphysis to the posterior border of the ramus. Local differences of the mental foramen may occur in a population. Prior to surgery knowledge of the most common location of the foramen peculiar to a local population may enable effective mental block anaesthesia to be provided.

Effect of radiotherapy on psychiatric disorder in patients with head and neck cancer.

PURPOSE: The aim of this prospective study was to evaluate the effects of radiotherapy (RT) on psychiatric disorder in patients undergoing RT for head and neck cancer. MATERIALS AND METHODS: The prospective study included 51 patients with head and neck cancer. The diagnosis of psychiatric disorder was made by Diagnostic and Statistical Manual of Mental Disorders, 4th edition criteria. Severity of psychopathology was assessed by the Hamilton Depression Rating Scale (HAM-D). RESULTS: Although HAM-D score increased after RT (from 4 [0-26] to 7 [0-24]), this increase was not significant (P = 0.108). Fourteen (27.5%) of 51 patients had a psychiatric disorder before RT treatment; adjustment disorder in 6, depression in 4, sleep disorder in 3, anxiety disorder in 1 patient. On the other hand, 16 (31.4%) of 51 patients had a psychiatric disorder after RT treatment; adjustment disorder in 6, depression in 5, sleep disorder in 4, anxiety disorder in 1 patient. There was no significant difference between two periods in terms of the prevalence of psychiatric disorder (P = 0.721). CONCLUSIONS: The presence of psychiatric disorder was high in patients with head and neck cancer even before RT. Similarly, its high rate continued after RT. However, there is no significant effect of RT on development of psychiatric disorder.

What does the broken brain say to the neuroscientist? Oscillations and connectivity in schizophrenia, Alzheimer's disease, and bipolar disorder.

The application of the concept and methods of brain oscillations has been an important research area in neurosciences. In the last decades, besides the application in cognitive processes, the study of changes in brain oscillations in diseases has also become an important focal point of research. In the present paper, some remarkable examples in three different diseases are taken into consideration: 1) schizophrenia (SZ), 2) Alzheimer's disease (AD), 3) bipolar disorders (BD). In the current literature, decreased oscillations in cortical recordings are observed in most of the pathologies. For example, decrease of gamma activity in SZ, decrease of delta activity in almost all diseases, as well as frequency shifts in alpha and the lower frequencies were recorded. However, there are also paradoxical cases in which an increase of oscillatory activities is observed. In BD, whereas alpha activity is greatly decreased, a huge increase of beta activity is observed. Or, in SZ, a paradoxical increase of gamma activity can be observed during cognitive loading. We also observed paradoxical changes in the analysis of connectivity. In AD, we find that alpha, delta, and theta coherences between distant parts of the cortex are greatly decreased, whereas in the gamma band, event-related coherences attain very high values. The comparison of the results and paradoxical changes in diseases may lead to important conclusions related to the web of oscillations and neurotransmitters. In turn, we could gain new insights to approach "brain function", in general.

Event-related theta oscillations during working memory tasks in patients with schizophrenia and healthy controls.

Altered frontal lobe activity and executive control associated with working memory (WM) dysfunction are recognized as core deficits in schizophrenia. These impairments have been discussed as being associated with deficits in self-regulated action monitoring and anticipatory action plan generation. To study electrophysiological correlates of executive control -- specifically action monitoring and action rule switching -- under varying WM load, we used a paradigm derived from classic N-back (WM) tasks and requiring monitoring of simple actions. We focused on event-related changes in post-stimulus theta oscillatory activity during varying cognitive and WM demand in healthy controls and schizophrenia patients. The results show significant WM load and rule-switching-related increases of post-stimulus theta amplitude at fronto-central locations in controls. In patients with schizophrenia, there was no such modulation, but -- apart from an increased early theta at left temporal locations -- generally reduced late theta responses in all tasks and at all locations. Furthermore, the patients with schizophrenia showed significant differences in their error patterns, which imply differences in automation and anticipation of actions between controls and patients. These findings suggest that theta oscillations are involved in mediating frontal lobe activity and functions related to enhanced executive control. We conclude that the patients with schizophrenia showed deficits in acquiring a mental task set which appear to be associated with impairments in action monitoring and task-specific regulation of executive control.

Gamma responses in the EEG: elementary signals with multiple functional correlates.

The hypothesis that electric and magnetic brain activity in the gamma range is related to cognitive processing is based mainly on experiments with complex stimuli. Our report, however, demonstrates the existence of gamma responses to "extremely simple" visual stimuli in several intracranial structures of the cat brain. This implies that the functional correlates of gamma activity are diverse, encompassing cognitive as well as primary sensory processing. The ubiquity of gamma responses strongly suggests the universal importance of gamma rhythms as functionally relevant elementary signals of the brain.

Gamma responses in the EEG: elementary signals with multiple functional correlates.

The hypothesis that electric and magnetic brain activity in the gamma range is related to cognitive processing is based mainly on experiments with complex stimuli. Our report, however, demonstrates the existence of gamma responses to "extremely simple" visual stimuli in several intracranial structures of the cat brain. This implies that the functional correlates of gamma activity are diverse, encompassing cognitive as well as primary sensory processing. The ubiquity of gamma responses strongly suggests the universal importance of gamma rhythms as functionally relevant elementary signals of the brain.

VEP-interhemispheric transfer time in 20-32 Hz band in man.

This research aimed to investigate callosal transfer in the different frequency bands of VEP to lateralized reversal of checkerboard pattern as stimuli. The chosen band pass filters (4-8 Hz, 8-15 Hz, 15-20 Hz, 20-32 Hz) were applied to the VEPs of subjects, and four different components for each VEP were obtained. Latency differences between hemispheres for digitally unfiltered and filtered VEPs were computed to estimate IHTT. Different IHTTs in the theta (17 ms), alpha (9 ms) and beta1 (7 ms) bands from right to left and from left to right were estimated, supporting the previous report. Furthermore, a transfer within 4.5 ms from right to left in the 20-32 Hz band for the occipital lobe was found. In conclusion, our findings suggest that the frequency analysis of VEP to lateralized stimuli give us additional information, relating to the types of callosal fibers.

Distinguishing hepatitis B virus (HBV) genotype D from non-D by a simple PCR.

Different HBV genotypes have characteristic geographical distribution, which is important epidemiologically. HBV strains have been classified into eight different genotypes (A-H) on the basis of >8% differences in the entire genomic sequence. Genotypes A and D are predominant in Europe, Africa, and the USA, genotypes B and C are restricted to East Asia, genotype E is found in Africa, and genotype F is found in indigenous populations in Central and South America. Genotype D is prevalent in the Turkish population. HBV genotype D shows a 33-bp deletion in the pre-S1 region that accounts for their smaller genomic size (3182 bp). This deletion can be used to facilitate the identification of genotype D. A primer in the pre-S1 region was designed to discriminate genotype D from non-D by PCR. Sixty genotype D (40 acute and 20 chronic) and 4 genotype A sera identified by restriction fragment length polymorphism (RFLP) were included in the study. Using this simple PCR method, all genotype D sera were identified correctly and the test was able to detect HBV DNA at 1000 genomes per ml. An advantage of this method is that it can differentiate in a mixture of genotypes (genotype D from non-D) provided that one isn't present below 1 x 10(4) copies/ml. In conclusion this method is rapid (approximately 5h) and it will contribute to the epidemiological study of HBV in high prevalence areas of genotype D. It can also differentiate between genotype D from non-D in cases of co-infection.

Acute hepatitis B virus infection in Turkey: epidemiology and genotype distribution.

The aim of this study was to investigate the prevalence of hepatitis B virus (HBV) genotypes in Turkey. Epidemiological and clinical data for 158 patients with acute HBV infection from 22 medical centres in the period February 2001 to February 2002 were collected prospectively. HBV genotyping was based on analysis of restriction fragment length polymorphisms and nested PCR. There were 59 female and 99 male patients, with a mean age of 34.2 +/- 15.6 years. The most common probable transmission route was blood contact in 63 (41.1%) cases, but was unknown in 78 (49.4%) cases. The mean alanine aminotransferase level was 1718 +/- 1089 IU/L. Four of the 158 patients (2.5%) died because of fulminant hepatitis. One year after discharge, 11 (10.6%) of 103 cases were positive for hepatitis B surface antigen (HBsAg) and 80 (77.7%) were positive for anti-HBsAg. Genotype determination was unsuccessful in 11 cases because of a negative PCR; genotype D was found in the remaining 147 cases. The results suggested that acute HBV infection constitutes a significant health problem in Turkey and that genotype D is predominant.

Informal consultations in infectious diseases and clinical microbiology practice.

Informed consultation between physicians is an important part of medical practice. The aim of the study was to evaluate the nature and frequency of such consultations in infectious diseases and clinical microbiology practice. This study was done in five university hospitals. Twenty-one infectious diseases and clinical microbiology specialists participated in informal ('curbside') consultations. In a written questionnaire, physicians were asked to report the number and nature of the informal consultations (ICs) they were asked to provide. A total three hundred and sixty-two such consultations were carried out during a three-month period. The ICs occurred most frequently in the hospital (82.3%). Most of the ICs from outside the hospital were by telephone. Most of the ICs (54.4%) were requested by fellows of specialists. 78.7% of the ICs were requested during working hours. 58.8% of consultations took less than 5 min, 18.8% took 6-10 min, 15.2% took 11-20 min, and 7.2% took over 20 min. The four most common reasons for obtaining ICs were to: help to select an appropriate treatment plan (41.4%), help to select an appropriate prophylaxis (19.3%), interpret laboratory data (10.2%), and provide information about antibiotics (10.2%). 30.1% of ICs resulted in subsequent formal consultation and only four patients (1.1%) were transferred to the consultants' clinics. Informal consultations are a frequent occurrence in the practice of infectious diseases and clinical microbiology (ID&CM). Physicians use this sort of consultation to select an appropriate treatment plan and obtain medical information. This study confirms the importance of the ID&CM specialists as a resource for medical personnel.

Visual evoked potential interhemispheric transfer time in different frequency bands.

OBJECTIVE: Visual evoked potentials (VEP) have been used to estimate interhemispheric transfer time (IHTT). However, the complex wave of VEP is most probably formed by different generators of neural populations that act through different frequency channels. If the main peaks of VEP are established by different types of generators, which can also be connected to each other by a different type of callosal fibres, we would be able to estimate a wide range of various IHTT by measuring the latency between time-locked peaks of narrow band-pass filtered VEP. This research aimed to test this hypothesis. METHODS: Nine right-handed men were presented with a reversal of a checkerboard pattern as stimuli at RVF or LVF, and EEG was recorded at O1, O2, P3, P4. The grand-averaged VEPs were transformed to the frequency domain by means of the fast Fourier transform to obtain the amplitude frequency characteristics. Band-pass filters were chosen adequately, according to tuning frequencies indicated by clear peaks in the amplitude frequency characteristics. The chosen band pass filters (4-8 Hz, 8-15 Hz, 15-20 Hz, 20-32 Hz) were applied to the VEP of the subjects, and 4 different components of VEPs for each VEP were obtained. The latency of P100 and N160 of unfiltered VEP was measured. In the band-pass digital filter applied VEPs, positive and negative peaks, which are consistent with P100 and N160, were measured for each subject. Latency differences between hemispheres for digitally unfiltered and filtered VEPs were computed to estimate IHTT. RESULTS: In the different frequency bands, different IHTTs were estimated, ranging from 3 ms to 30 ms. Approximately 16 ms for theta band, 11 ms for alpha band, 6 ms for 15-20 Hz and 3 ms for 20-32 Hz bands were found. CONCLUSIONS: Our findings support the hypothesis which states that unfiltered VEPs provide us with only a rough estimation of IHTT. Also, they are consistent with anatomical findings that describe callosal fibres of varying dimensions, predicting various velocities between hemispheres.

Electroencephalogram alpha (8-15 Hz) responses to visual stimuli in cat cortex, thalamus, and hippocampus: a distributed alpha network?

To investigate possible functional correlates of alpha (8-15 Hz) oscillations in the electroencephalogram (EEG) intracranial recordings in cats (from thalamus, occipital cortex, and hippocampus) were performed. In response to visual stimuli, event-related alpha oscillations were observed. Such alpha responses were found not only in a specific sensory (visual) pathway but also in the hippocampus, hinting at a possible distributed alpha response system.