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11.

Objective

To determine the frequency and type of human papillomavirus (HPV) in oral squamous cell carcinomas (OSCC), as well as to identify a possible association between HPV infection and the expression pattern of p53 and bcl-2, and identify whether the oral HPV infection is a characteristic finding in our sample.

Methods

We performed polymerase chain reaction and dot blot hybridization for the detection of HPV DNA in paraffin sections as well as immunohistochemical analysis of p53 and bcl-2 in our sample.

Results

Twenty-six cases (29.5%) were positive for the virus by PCR. Dot blot hybridization identified HPV 18 in 21 (80.8%) cases, HPV 16 in one (3.8%) case and a combination of the two types in the four (15.4%) remaining cases. No other type of HPV was detected in the sample. Immunohistochemistry showed p53 in 26 (60.4%) cases and bcl-2 in 17 (39.5%) ones. No significant association was observed between the presence of HPV and the expression of the proteins studied (p = 0.988 and p = 0.748, respectively).

Conclusions

Although this investigation have detected only 29.5% of HR-HPV DNA in OSCC, it is possible that this virus contribute to the development of some case of this tumor. Furthermore, it seems that the immunohistochemical expression of p53 and bcl-2 and the presence of HPV DNA are independent events in OSCC.  相似文献   
12.
13.
This work analyzes the genotoxicity potential, in the G2 phase of the cellular cycle, of an amphotericin B (AmB) commercially available form (Fungizone), and correlates it with the physicochemical properties of this product in aqueous media. The genotoxic studies were performed using peripheral blood lymphocytes from human donors. The chromosome aberrations and mitotic index were determined. Absorption spectra of Fungizone were obtained by dispersion of the stock solution in water for injection at various AmB concentrations, and using different cuvette path lengths for spectrophotometric determination. The absorption spectra of Fungizone in water are concentration dependent. High concentrations of Fungizone present a spectrum with an intense band at 340 nm, characteristic of AmB self-association. Conversely, at low concentrations, the spectra are similar to those obtained with AmB in methanol, with a positive band at 409 nm, assigned to AmB monomeric form. Similarly, the cytogenetic analysis shows an important decrease on the mitotic index, which is also concentration dependent when compared with control. Furthermore, the chromosome aberrations present a small, not statistically significant, increase only at the highest concentration. The results suggest that the Fungizone presents a cytotoxicity similar to membrane pore formation in mammalian cells that depends on the existence of self-associated AmB. In the presence of only monomeric forms, this phenomenon disappears. However, no genotoxicity was observed in this study.  相似文献   
14.
Flavonoids are a diverse family of plant compounds that are involved in pigmentation, protection, and endogenous regulation. Flavonoids also have medicinal applications, suggesting that they may exert chemoprotective effects. However, some studies have shown, that some plant flavonoids have oxidative and toxic effects, including those produced by Schinus terebinthifolius. In Brazil, extracts of this plant are widely used for medical purposes. In this study, we analyzed the mutagenic potential of two flavonoid‐enriched fractions from Brazilian pepper tree stem bark using Escherichia coli CC strains deficient and proficient in enzymes involved in the DNA repair of oxidative lesions. The highest mutagenic response was detected in the CC104mutMmutY strain but CC104mutY showed a higher mutation frequency than CC104mutM. The spectrum of mutations induced in plasmid DNA is composed of mutations typically caused by oxidative lesions. However, a new type of lesion must be occurred to explain the cytotoxicity, higher mutation rates in the CC104mutY strain, and the rare A:T → T:A and G:C → C:G transversions found in this work.  相似文献   
15.

Background

Sensory phenomena (SP) are uncomfortable feelings, including bodily sensations, sense of inner tension, “just-right” perceptions, feelings of incompleteness, or “urge-only” phenomena, which have been described to precede, trigger or accompany repetitive behaviours in individuals with obsessive–compulsive disorder (OCD). Sensory phenomena are also observed in individuals with tic disorders, and previous research suggests that sensorimotor cortex abnormalities underpin the presence of SP in such patients. However, to our knowledge, no studies have assessed the neural correlates of SP in patients with OCD.

Methods

We assessed the presence of SP using the University of São Paulo Sensory Phenomena Scale in patients with OCD and healthy controls from specialized units in São Paulo, Brazil, and Barcelona, Spain. All participants underwent a structural magnetic resonance examination, and brain images were examined using DARTEL voxel-based morphometry. We evaluated grey matter volume differences between patients with and without SP and healthy controls within the sensorimotor and premotor cortices.

Results

We included 106 patients with OCD and 87 controls in our study. Patients with SP (67% of the sample) showed grey matter volume increases in the left sensorimotor cortex in comparison to patients without SP and bilateral sensorimotor cortex grey matter volume increases in comparison to controls. No differences were observed between patients without SP and controls.

Limitations

Most patients were medicated. Participant recruitment and image acquisition were performed in 2 different centres.

Conclusion

We have identified a structural correlate of SP in patients with OCD involving grey matter volume increases within the sensorimotor cortex; this finding is in agreement with those of tic disorder studies showing that abnormal activity and volume increases within this region are associated with the urges preceding tic onset.  相似文献   
16.

Objective

To identify neuropsychological predictors of treatment response to cognitive–behavioral therapy (CBT) and fluoxetine in treatment-naïve adults with obsessive–compulsive disorder (OCD).

Method

Thirty-eight adult outpatients with OCD underwent neuropsychological assessment, including tasks of intellectual function, executive functioning and visual and verbal memory, before randomization to a 12-week clinical trial of either CBT or fluoxetine. Neuropsychological measures were used to identify predictors of treatment response in OCD.

Results

Neuropsychological measures that predicted a better treatment response to either CBT or fluoxetine were higher verbal IQ (Wechsler Abbreviated Scale of Intelligence) (p = 0.008); higher verbal memory on the California Verbal Learning Test (p = 0.710); shorter time to complete part D (Dots) (p < 0.001), longer time to complete part W (Words) (p = 0.025) and less errors on part C (Colors) (p < 0.001) in the Victoria Stroop Test (VST). Fewer perseverations on the California Verbal Learning Test, a measure of mental flexibility, predicted better response to CBT, but worse response to fluoxetine (p = 0.002).

Conclusion

In general, OCD patients with better cognitive and executive abilities at baseline were more prone to respond to either CBT or fluoxetine. Our finding that neuropsychological measures of mental flexibility predicted response to treatment in opposite directions for CBT and fluoxetine suggests that OCD patients with different neuropsychological profiles may respond preferentially to one type of treatment versus the other. Further studies with larger samples of OCD patients are necessary to investigate the heuristic value of such findings in a clinical context.  相似文献   
17.
Obsessive-compulsive disorder (OCD) is a frequent, disabling disorder with high rates of treatment resistance. Transcranial direct current stimulation (tDCS) is a safe, tolerable noninvasive neuromodulation therapy with scarce evidence for OCD. This double-blind, randomized, and sham-controlled study investigates the efficacy of tDCS as add-on treatment for treatment-resistant OCD (failure to respond to at least one previous pharmacological treatment). On 20 consecutive weekdays (4 weeks), 43 patients with treatment-resistant OCD underwent 30 min active or sham tDCS sessions, followed by a 8 week follow-up. The cathode was positioned over the supplementary motor area (SMA) and the anode over the left deltoid. The primary outcome was the change in baseline Y-BOCS score at week 12. Secondary outcomes were changes in mood and anxiety and the occurrence of adverse events. Response was evaluated considering percent decrease of baseline Y-BOCS scores and the Improvement subscale of the Clinical Global Impression (CGI-I) between baseline and week 12. Patients that received active tDCS achieved a significant reduction of OCD symptoms than sham, with mean (SD) Y-BOCS score changes of 6.68 (5.83) and 2.84 (6.3) points, respectively (Cohen’s d: 0.62 (0.06–1.18), p = 0.03). We found no between-group differences in responders (four patients in the active tDCS and one in the sham group). Active tDCS of the SMA was not superior to sham in reducing symptoms of depression or anxiety. Patients in both groups reported mild adverse events. Our results suggest that cathodal tDCS over the SMA is an effective add-on strategy in treatment-resistant OCD.Subject terms: Anxiety, Drug development  相似文献   
18.
Objective: To compare the performance of patients with obsessive–compulsive disorder (OCD) refractory to conventional treatments to healthy controls according to the Frontal Systems Behaviour Scale (FrSBe), comparing the scale scores within each group (Self or Family) and correlating FrSBe with Y-BOCS, DY-BOCS, tic disorder and age of first symptoms.

Method: Twenty OCD patients and 20 healthy controls were assessed using the FrSBe, a scale designed to evaluate frontal syndromes.

Results: The patients had higher scores when compared with the control group (p value < .001) in terms of total score on the scale for both profile forms (Self and Family). In addition, there was a significant difference between the scores reported by the patients and their respective relatives. However, no correlation was observed between the scale and the other variables.

Conclusions: The scale was able to clearly differentiate patients with OCD from healthy controls. This finding suggests that the FrSBe can be used not only in neurologic patients but also in psychiatric cases such as refractory OCD.  相似文献   
19.

Environmental factors are at least as important as genetic factors for the development of obsessive–compulsive symptoms (OCS), but the identification of such factors remain a research priority. Our study aimed to investigate the association between a broad scope of potential risk factors and OCS in a large community cohort of children and adolescents. We evaluated 1877 participants and their caregivers at baseline and after 3 years to assess various demographic, prenatal, perinatal, childhood adversity, and psychopathological factors. Mean age at baseline was 10.2 years (SD 1.9) and mean age at follow-up was 13.4 years (SD 1.9). Reports of OCS at baseline and follow-up were analyzed using latent variable models. At preliminary regression analysis, 15 parameters were significantly associated with higher OCS scores at follow-up. At subsequent regression analysis, we found that eight of these parameters remained significantly associated with higher follow-up OCS scores while being controlled by each other and by baseline OCS scores. The significant predictors of follow-up OCS were: lower socioeconomic status (p = 0.033); lower intelligence quotient (p = 0.013); lower age (p < 0.001); higher maternal stress level during pregnancy (p = 0.028); absence of breastfeeding (p = 0.017); parental baseline OCS (p = 0.038); youth baseline anxiety disorder (p = 0.023); and youth baseline OCS scores (p < 0.001). These findings may better inform clinicians and policymakers engaged in the mental health assessment and prevention in children and adolescents.

  相似文献   
20.
Several therapeutic properties have been described for Eugenia caryophyllata (clove). In the present study the infusion of E. caryophyllata was evaluated in a series of bacterial and cell-free assays in order to determine genotoxic potential. Negative results were obtained in the SOS chromotest and in the Salmonella reversion assay using strains TA97a, TA98, TA100, and TA102. However, in a forward mutagenesis assay an increase in mutagenesis and high cytotoxicity was observed with the CC104 mutMmutY strain, suggesting that oxidative DNA damage occurred. The treatment of plasmid with clove infusion showed that DNA strand breaks and sites recognized by formamidopyrimidine-DNA-glycosylase (FPG/MutM) were generated. Data suggest that the occurrence of oxidative DNA damage, with low mutagenic potential, may also be involved in the cytotoxicity attributed to clove infusion.  相似文献   
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