Development of a valid and reliable instrument for the assessment of quality of life in parents of children with clefts.

PURPOSE: Orofacial clefts are the most common congenital malformations that affect craniofacial structures. Studies show that they have a major influence on psychological development of the patient, and on their families. A review of the literature showed a lack of specific questionnaires for children and their parents. This study investigated the impact of orofacial clefts in children on the quality of life of their parents. In addition, the results of the treatment and the quality of work of the health team members involved in this process were evaluated. MATERIALS AND METHODS: For the purpose of this study, an original questionnaire was made to analyse the effect of orofacial clefts in children who had undergone surgery on the quality of life of 73 of their parents. The questionnaire consisted of 28 simple statements, which were evaluated with a 5-degree Likert scale (from 1-fully disagree to 5-fully agree), did not require any specific additional clarification, and were easy to complete. RESULTS: Analysis of areas of the questionnaire that applied to the parents, resulted in two subscales, parental social health and child social health, which had satisfactory Cronbach's coefficients (0.907 and 0.897, respectively). However, some issues had a relatively poor coefficient of internal consistency, which justified their expulsion from the final model of the parent questionnaire. CONCLUSION: The questionnaire developed for this study comprised two subscales concerned with the social health of parents/respondents and the social health of adolescents, as perceived by the parents. It was a valid and reliable instrument, and it showed satisfactory quality of life for parents of adolescents with clefts.

Neurotypic cell attachment and growth on III-nitride lateral polarity structures.

III-nitride materials have recently received increasing levels of attention for their potential to successfully interface with, and sense biochemical interactions in biological systems. Expanding on available sensing schemes (including transistor-based devices,) a III-N lateral polarity structure capable of introducing quasi-phase matching through a periodic polarity grating presents a novel platform for second harmonic generation. This platform constitutes a non-linear optical phenomenon with exquisite sensitivity to the chemical state of a surface or interface. To characterize the response of a biological system to the nanostructured lateral polarity structures, we cultured neurotypic PC12 cells on AlGaN with varying ratios of Al:Ga - 0, 0.4, 0.6, and 1 - and on surfaces of varying pitch to the III-polar vs. N-polar grating - 5, 10, 20 and 50 µm. While some toxicity associated with increasing Al is observed, we documented and quantified trends in cell responses to the local material polarity and nanoscale roughness. The nitrogen-polar material has a significantly higher nanoscale roughness than III-polar regions, and a 80-200 nm step height difference between the III-polar and N-polar materials in the lateral polarity configuration generates adequate changes in topography to influence cell growth, improves cell adhesion and promotes cell migration along the direction of the features. As the designed material configuration is further explored for biochemical sensing, the lateral polarity scheme may provide a route in assessing the non-specific protein adsorption to this varying nano-topography that drives the subsequent cell response.

Physisorption of functionalized gold nanoparticles on AlGaN/GaN high electron mobility transistors for sensing applications.

AlGaN/GaN high electron mobility transistors (HEMTs) were used to measure electrical characteristics of physisorbed gold nanoparticles (Au NPs) functionalized with alkanethiols with a terminal methyl, amine, or carboxyl functional group. Additional alkanethiol was physisorbed onto the NP treated devices to distinguish between the effects of the Au NPs and alkanethiols on HEMT operation. Scanning Kelvin probe microscopy and electrical measurements were used to characterize the treatment effects. The HEMTs were operated near threshold voltage due to the greatest sensitivity in this region. The Au NP/HEMT system electrically detected functional group differences on adsorbed NPs which is pertinent to biosensor applications.

"Dip-Pen" nanolithography on semiconductor surfaces.

Dip-Pen Nanolithography (DPN) uses an AFM tip to deposit organic molecules through a meniscus onto an underlying substrate under ambient conditions. Thus far, the methodology has been developed exclusively for gold using alkyl or aryl thiols as inks. This study describes the first application of DPN to write organic patterns with sub-100 nm dimensions directly onto two different semiconductor surfaces: silicon and gallium arsenide. Using hexamethyldisilazane (HMDS) as the ink in the DPN procedure, we were able to utilize lateral force microscopy (LFM) images to differentiate between oxidized semiconductor surfaces and patterned areas with deposited monolayers of HMDS. The choice of the silazane ink is a critical component of the process since adsorbates such as trichlorosilanes are incompatible with the water meniscus and polymerize during ink deposition. This work provides insight into additional factors, such as temperature and adsorbate reactivity, that control the rate of the DPN process and paves the way for researchers to interface organic and biological structures generated via DPN with electronically important semiconductor substrates.

CYP2D6 genotyping in patients on psychoactive drug therapy.

The polymorphic isoenzyme CYP2D6 has a major role in the oxidative metabolism of many deal of psychoactive drugs. Its six mutant alleles (null alleles *3, *4, *5, *6, *7 and *8) encode for inactive enzyme molecules. A carrier of two mutant alleles is considered a poor metabolizer phenotype, while a carrier of only one damaged allele is considered an intermediate metabolizer phenotype. The aim of the study was to assess the prevalence of null alleles in a group of psychiatric patients suffering from depression (n=49) and schizophrenia (n=86) in comparison with healthy individuals (n=145) by the method of multiplex allele specific PCR. Only CYP2D6*3,*4 and *6 mutant alleles were found in the study subjects. No significant difference between the depression and control groups was found for allele prevalence, genotype or phenotype distribution (p>0.05). However, a significant difference was observed between schizophrenic patients and controls for allele frequency (p=0.002), genotype distribution (p=0.016), and phenotype prevalence (p=0.018). The odds ratio of 2.542 for 2D6*4 suggested a significant association between this allele and schizophrenia, significantly contributing to poor metabolizer phenotype (odds ratio=5.020). The relationship between CYP2D6 gene polymorphism and side effects in schizophrenic patients undergoing long-term psychoactive drug therapy was investigated. A significant difference was obtained for allele prevalence (p=0.002), genotype (p=0.029), and phenotype (p=0.002) distribution between patients without and with side effects. A relative risk of 2.626 and 5.333 for 2D6*4 and 2D6*6, respectively, and of 7.08 for poor metabolizer phenotype suggested a significant association between the hereditary susceptibility for a particular type of drug metabolism (defect alleles) and side effects. These preliminary results suggest that the CYP2D6 genotyping appears to be useful for predicting risks for side effects of psychoactive drugs in schizophrenic patients, but their usefulness should be further explored.

Genotyping of CYP2D6 in Parkinson's disease.

Parkinson's disease is characterized by progressive degradation of dopaminergic neurons. Cytochrome P450 CYP2D6 enzyme is one of the most investigated and highly polymorphic isoforms, which metabolizes many drugs and is also involved in the metabolism of dopamine. Using allele-specific multiplex PCR, we genotyped 186 subjects for CYP2D6 *3, *4, *6, *7, and *8 alleles in order to estimate allelic, genotype and predicted phenotype frequencies in the control and patient groups, and to investigate the possible statistical difference between Parkinson's disease patients (n=41) and healthy controls (n=145). Parkinson's disease patients were further divided into two subgroups according to Hoehn and Yahr staging of the disease (HY), i.e. groups with HY stage less than 2.5 (HY <2.5; n=27) and more than 2.5 (HY >2.5; n=14). A subgroup of Parkinson's disease patients exhibiting side effects such as "on-off" phenomenon and dyskinesia (both suggesting favorable response to therapy) were compared with a subgroup of patients showing no such response. The preliminary results of this study showed that only the prevalence of CYP2D6 *4 allele differed significantly between the PD patients and control group (20.7% vs. 11.0%; p=0.027; RR=2.1, 95%CI 1.113-3.994). In the HY >2.5 subgroup, the CYP2D6*4 allelic difference was even greater (25.0% vs. 11.0% in controls; p=0.062, RR=2.69, 95%CI 1.090-6.624). Genotype frequencies differed only in the HY >2.5 subgroup, however with a level of significance of p=0.095.

The cytochrome P450 2D6 (CYP2D6) gene polymorphism among breast and head and neck cancer patients.

The prevalence of CYP2D6*3 and CYP2D6*4 alleles in normal controls and cancer patients was studied using the reliable PCR-SSCP method. In the control group (n=144), four subjects (2.8%) were found to carry CYP2D6*3 allele (heterozygote), while 30 (20.8%) subjects carried CYP2D6*4 allele (18.8% heterozygotes, 2.1% homozygotes). One (1.3%) of the breast cancer (BC) patients (n=76) carried CYP2D6*3 allele, but 24 (31.6%) carried CYP2D6*4 allele (26.3% heterozygotes, 5.3% homozygotes). In the head and neck cancer (HNC) group (n=56), two (3.6%) patients were heterozygous for CYP2D6*3 mutation and 15 (26.8%) for CYP2D6*4 mutation. Fourteen of 56 (25%) and one of 56 (1. 8%) of these patients carried heterozygous and homozygous mutations, respectively. In controls, 2.1% were identified as poor metabolizers (PM), 76.4% as extensive metabolizers (EM), and 21.5% as intermediate heterozygotes (IEM). In BC group, 5.3, 27.6 and 67.1% were classified as PM, IEM and EM, respectively. In HNC group, the incidence of PM was 1.8, but as many as 28.6% were identified as IEM phenotypes.

Detection of CYP2D6*3 and 2D6*4 allelic variants by PCR-restriction fragment length polymorphism.

The mutant of CYP2D6*3 allele with A2637 deletion in exon 5 and the mutant of CYP2D6*4 allele G1934-->A, splice site defect are among the most common polymorphic alleles of CYP2D6 gene, resulting in a decreased or no activity of CYP isoenzyme. In this study, a reliable polymerase chain reaction-restriction fragment length polymorphism method for identification of CYP2D6*3 and CYP2D6*4 alleles was used to investigate the genotype and phenotype prevalence in the groups of normal controls, and of cirrhosis and cancer patients. The results showed none of 36 controls genotyped for 2D6*3 and 2D6*4 allele to have the 2D6*3 allele with frameshift mutation in exon 5, while 33% (n=12) were found to bear the 2D6*4 allele with G to A mutation at the intron 3-exon 4 junction. In breast cancer patients (n=35) genotyped for 2D6*3 and 2D6*4 alleles, none with 2D6*3 allele was found either, but 60% (n=18) were found to bear the 2D6*4 allele. In patients with head and neck squamous cell cancer, there was only one subject with 2D6*3 allele and he was heterozygous. Among them, as many as ten (40%) patients were found to bear 2D6*4 allele. In the cirrhosis group, none of the patients was found to have the 2D6*3 allele, while the CYP2D6*4 allele was found in 23% (n=6) patients. The phenotype predicted according to the genotype was as follows: in the control group, 3% of individuals were identified as poor metabolizers, 70% as extensive metabolizers, and 27% as heterozygote extensive metabolizers. In the group of breast cancer, 7% of the patients were identified as poor metabolizer, 57% as extensive metabolizer and 36% as phenotype. In squamous cell cancer and cirrhosis patients, the incidence of poor metabolizer was zero, and of heterozygotes extensive metabolizer 42% and 31%, respectively.