Antimicrobial effects of sodium hypochlorite and Er,Cr:YSGG laser against Enterococcus faecalis biofilm.

AIMS: The aim of this study was to investigate the antimicrobial effect of Erbium, chromium-doped yttrium, scandium, gallium, and garnet (Er,Cr:YSGG) laser with and without NaOCl solution. A total of 81 extracted human mandibular premolar teeth were used. MATERIALS AND METHODS: After root canal preparation and sterilization, the samples were inoculated with E. faecalis for 24 hours. The specimens were divided into 4 experimental groups. Group 1 (n = 25) was irradiated with 2 W laser, group 2 (n = 25) was irradiated with 0.75 W laser in combination with 2.5% NaOCl, group 3 (n = 25) was irrigated with 5% NaOCl and group 4 (n = 6) was not treated. Statistical analysis was performed by using Wilcoxon Signed Ranks, Mann-Whitney U and Kruskal-Wallis H tests. RESULTS: The combination of 0.75 W laser with 2.5% NaOCl regime was found to be just as effective at inhibiting the growth of E. faecalis and sterilization of all root canals as 5% NaOCl irrigation (P > 0.001). The 2 W laser had significant bactericidal effect in infected root canals however it did not eradicate all bacteria. The SEM observations were in accordance with the microbiologic findings. CONCLUSIONS: Within the limitations of this laboratory study, NaOCl irrigation improved the antimicrobial effect of Er,Cr:YSGG laser irradiation. When the toxic effects of high percentage of NaOCl was considered, the combination of low-powered laser and low concentration of NaOCl can be used as an effective disinfection method in root canal treatment.

Phenotypic differentiation is associated with divergent sexual selection among closely related barn swallow populations.

Sexual selection plays a key role in the diversification of numerous animal clades and may accelerate trait divergence during speciation. However, much of our understanding of this process comes from phylogenetic comparative studies, which rely on surrogate measures such as dimorphism that may not represent selection in wild populations. In this study, we assess sexual selection pressures for multiple male visual signals across four barn swallow (Hirundo rustica) populations. Our sample encompassed 2400 linear km and two described subspecies: European H. r. rustica (in the Czech Republic and Romania) and eastern Mediterranean H. r. transitiva (in Israel), as well as a potential area of contact (in Turkey). We demonstrate significant phenotypic differentiation in four sexual signalling axes, despite very low-level genomic divergence and no comparable divergence in an ecological trait. Moreover, the direction of phenotypic divergence is consistent with differences in sexual selection pressures among subspecies. Thus, H. r. transitiva, which have the darkest ventral plumage of any population, experience directional selection for darker plumage. Similarly, H. r. rustica, which have the longest tail feathers of any population, experience directional selection for elongated tail feathers and disruptive selection for ventral plumage saturation. These results suggest that sexual selection is the primary driver of phenotypic differentiation in this species. Our findings add to growing evidence of phenotypic divergence with gene flow. However, to our knowledge, this is the first study to relate direct measures of the strength and targets of sexual selection to phenotypic divergence among closely related wild populations.

Idiopathic scrotal calcinosis in a case who presented 20 years after the initiation of symptoms: a review of the literature.

Idiopathic scrotal calcinosis (ISC) is characterised by the presence of multiple firm scrotal nodules of unknown or controversial etiology. It is a rare, yet benign, entity of the scrotal skin. However, it affects the quality of life of the patients. Here, we describe a case report of ISC in a 50 year-old male patient with a 20 year-history of symptoms. Despite the delayed diagnosis, patient was treated with surgical excision succesfully. No recurrence has been seen by the end of the 3 years of follow-up. We also reviewed the literature.

Case report: multiple keratocystic odontogenic tumour in a non-syndromal pediatric patient.

BACKGROUND: Keratocystic odontogenic tumour (KCOT) is an odontogenic tumour which stems from the odontogenic organs mostly localised in the lower jaw, particularly posterior body and ascending ramus of the mandible. The majority of these tumours are single lesions. When detected in the jaw in multiple forms, these cysts are seen in association with Gorlin Goltz/Basal cell naevus syndrome. However a few cases of non-syndromal multiple keratocystic odontogenic tumour have been reported in the literature. CASE REPORT: We report a case of multiple keratocystic odontogenic tumour in a 13-year-old girl demonstrated by panoramic radiography and cone beam computed tomography (CBCT). The differential diagnosis, treatment and imaging modalities are also discussed.

A possible system for optimal donor kidney exchange in Turkey.

The lack of available deceased donors and the immunological incompatibility between the patients and their voluntary donor candidates make kidney exchange among donor-patient pairs a preferable solution performed locally by many organ transplantation centers in Turkey. However, maximum benefit from kidney exchange can only be achieved when the donor patient pool is maximized using a nationwide kidney exchange program. This work discusses kidney exchange practices worldwide to develop a nationwide exchange program in Turkey and related challenges.

Successful spontaneous pregnancy in a patient with rectal carcinoma treated with pelvic radiotherapy and concurrent chemotherapy: the unique role of laparoscopic lateral ovary transposition.

Concurrent administration of external beam pelvic radiotherapy (RT) and chemotherapy (CT) is an effective treatment modality for rectal cancer. In adults in reproductive age, one of the most important side-effects resulting from this treatment is gonadal toxicity. Fortunately, it is possible to protect the ovaries by transporting them out of the RT area through lateral ovary transposition (LOT), as a minimally invasive method, which is performed before the application of RT. A 24-year-old female was diagnosed as having rectal adenocarcinoma in May 2003, and she was scheduled to receive adjuvant 5-fluorouracil-based CT followed by concurrent chemoradiotherapy (CRT). Before the onset of the adjuvant treatments, laparoscopic LOT was performed, and the patient was followed-up appropriately. Although amenorrhea developed during the CRT, the menstrual cycle of the patient resumed without performing any medical treatment eight weeks after the completion of the CRT. In July 2005, the patient became pregnant spontaneously with no local or systemic recurrences of rectal cancer. The present case shows that ovarian functions can be successfully protected in rectal cancer patients receiving RT by laparoscopic LOT, and by modifying the RT fields.

Factors influencing cosmetic results after breast conserving management (Turkish experience).

We aimed to determine predictive factors affecting cosmetic results after breast conserving management in breast cancer. Data on 96 patients with 97 breast cancer cases, who had been admitted to Uludag University M.A. Radiotherapy Center between October 1995 and December 1998 and managed with breast-conserving treatment, were analysed to determine the factors affecting cosmetic outcome. Possible factors affecting cosmesis were grouped as patient-related, tumor-related and treatment-related. Mann-Whitney U test was used in univariate analyses whereas logistic regression was used in multivariate analyses. Median follow-up time was 29.5 months ranging between 11 and 53 months and median age at admission was 50 (range 22-84). Cosmetic results were grouped in five categories; excellent; good; fair; poor and, very poor, using criteria, such as presence of fibrosis, telangiectasia, shape of breast, asymmetry, status of areola, pigmentation. Treated breasts were scored by the patients, three radiation oncologists and a breast surgeon independently. In the analysis performed using scores given by the patients, cases with scores 3 and above (unsatisfactory) were compared with cases with scores below 3 (satisfactory). Eighty-two patients (84%) considered cosmetic result as satisfactory (excellent/good) whereas 15 patients (16%) considered unsatisfactory (fair/poor/very poor). In univariate analysis using Mann-Whitney U test, type of surgery (P=0.0655) was the statistically significant factors affecting cosmetic results. In multivariate analysis using logistic regression, tumor quadrant (P=0.0060) and elapsed radiation therapy days (P=0.0090) were the most significant factors. Median values were taken into consideration for the scores given by the physicians and cases with scores 3 and above (unsatisfactory) were compared with cases with scores below 3 (satisfactory). Eighty-two cases were evaluated as satisfactory (84%) whereas 15 cases were unsatisfactory (16%). In this set of data, patient age (P=0.0144), menopausal status (P=0.0111), institution which surgery was performed (P=0.0045), type of surgery (P=0.0044), placement of metallic clips (P=0.0083) and skin fibrosis (P=0.038) were found to be significant in univariate analysis using Mann-Whitney U test. In multivariate analysis using logistic regression, institution where surgery took place (P=0.0015), menopausal status (P=0.0087) and telangiectasia (P=0.0657) were the most significant factors.

Effects of Taxol plus radiation on the apoptotic and mitotic indices of mouse intestinal crypt cells.

PURPOSE: In this study we investigated the effect of Taxol, radiation, or Taxol plus radiation on highly proliferative normal tissue--the intestinal crypt cells of Swiss albino mice. MATERIALS AND METHODS: Swiss-albino mice, 3-4 months old, were used in this study. Taxol was administered by bolus intravenously through the tail vein. Radiation was given using a linear accelerator. There were four treatment categories, which comprised a total of 34 groups. Each group consisted of five animals. The first category was a control category which comprised one group (n = 5). The second treatment category was Taxol alone which comprised three groups (n = 15). The third treatment category was radiation alone which comprised three groups (n = 15). The fourth treatment category was Taxol plus radiation which comprised 27 groups (n = 135). Mice were killed 24 h after Taxol or radiation or combined administration using ether anesthesia. Using a light microscope, apoptotic and mitotic indices were counted on jejunal crypt cells of mice that were stained with hematoxylin-eosin. Differences between groups were statistically evaluated with Student's t-test. RESULTS: Taxol caused a dose-dependent increase in apoptosis (P = 0.045) and decreased the mitotic index (P = 0.006) at high doses. Similarly, radiation caused a dose-dependent increase in apoptosis (P = 0.046) and decreased the mitotic index (P = 0.299) at higher radiation doses. Compared to radiation alone, Taxol caused a significant induction of apoptosis (P = 0.010). In combination, no significant radiosensitizing effect of Taxol was observed (enhancement ratio < 1), when compared to radiation alone. However, an increase in apoptosis was observed after 24 h of Taxol exposure when compared to 12 or 48 h of Taxol exposure (P = 0.0001 and P = 0.0001). CONCLUSION: These findings suggest that Taxol did not cause a radiosensitizing effect in intestinal crypt cells. However, a 24-hour pretreatment of Taxol exposure followed by radiation caused significant induction of apoptosis and reduction of the mitotic index when compared to other Taxol timing sequences. Thus, the lack of a radiosensitizing effect of Taxol in these proliferative cells may be due to enhanced mitotic death rather than apoptotic death.

The relationship between genetic susceptibility to head and neck cancer with the expression of common fragile sites.

BACKGROUND: Numerous studies have recently been conducted to investigate genetic mechanisms in cancer causes and pathogenesis. Some of these studies have shown that there were certain specific chromosomal defects in normal cells of cancer patients and in their first-degree relatives. It was suggested that these individuals were susceptible to cancer development when compared with people without these defects. Materials and Methods Chromosomal anomalies, such as gaps, breaks, and acentric fragments, and fragile site expression rates were determined in peripheral blood lymphocyte cultures in 14 head and neck cancer patients, 17 first-degree relatives of these patients, and 20 healthy individuals as a control group in this study. RPMI 1640 medium, composed of aphidicolin, 5-bromodeoxyuridine, and caffeine were used for the induction of fragile sites. RESULTS: In cytogenetic and statistical evaluation, it was observed that both chromosomal aberration rates and fragile site expression frequencies in head and neck cancer patients and in their first-degree relatives were significantly greater than the control group (p <.05). It was found that fragile site expression was site specific in head and neck cancer patients and in their first-degree relatives. These specific sites were determined to be 1p21-22, 1q21, 1q25, 2q21, 2q31-33, 3p14, 16q22-23, 18q21, and 22q12 sites. CONCLUSIONS: These findings support studies showing that the fragile sites might be unstable factors in human genomes and their expression could be affected by some genetic factors, such as tumor suppressor genes and mismatch repair genes, and by some environmental factors, such as benzo (a) pyrene, dimethylnitrosamine, and dimethylsulfate. In conclusion, fragile sites may be playing an important role in the genetic tendency to head and neck cancer. Overexpression of these sites in normal lymphocytes may be used as a reliable marker to determine the genetic susceptibility in head and neck cancer patients and in their first-degree relatives.