Analysis of human papillomavirus prevalence and TP53 polymorphism in head and neck squamous cell carcinomas

Head and neck squamous cell carcinoma is a disease associated with tobacco and alcohol abuse. There is evidence that the oncogenic human papillomavirus (HPV) may also be a risk for upper aerodigestive tract cancers. High-risk HPVs encode two early proteins, E6 and E7, that can bind to p53 and pRb, respectively, and induce its degradation or inactivation. The TP53 gene has a single polymorphism at codon 72 of exon 4 that encodes either arginine (Arg) or proline (Pro). The purpose of this study was to evaluate the role of HPV infection and TP53 polymorphism in head and neck cancer. We analyzed 50 tumors, as well swabs of oral mucosa from 142 control individuals, with a polymerase chain reaction technique. The prevalence of HPV in controls was 10.6% and in cancer specimens 16%. The frequency distribution of genotypes in controls was 50% Arg/Arg, 43% Arg/Pro and 7% Pro/Pro; in tumors, it was 52% Arg/Arg, 32% Arg/Pro, and 16% Pro/Pro. Contrary to the results of some studies on cervical cancer, no association between any TP53 genotype or allele and the development of head and neck cancer was observed, regardless of HPV status, except for the Pro/Pro genotype, which is associated with the absence of HPV. The arginine allele appears to protect against head and neck cancers. Also, the data showed that HPV infection results in no increased risk of developing head and neck tumors.     

Bone Mineral Density and Androgen Levels in Elderly Males

To clarify the relationship of sex male hormones and bone in men, we studied in 140 healthy elderly men (aged 55–90 years) the relation between serum levels of androgens and related sex hormones, bone mineral density (BMD) at different sites, and other parameters related to bone metabolism. Our results show a slight decrease of serum-free testosterone with age, with an increase of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in a third of the elderly subjects studied. BMD decreased significantly with age in all regions studied, except in the lumbar spine. We found a positive correlation between body mass index (BMI) and BMD at the lumbar spine and femoral neck (P < 0.001). No relationship was found (uni- and multivariate regression analysis) between serum androgens or sex hormone-binding globulin (SHBG) and BMD. We found a positive correlation of vitamin D binding protein (DBP) and osteocalcin with lumbar spine BMD and with BMI, DBP, IGF-1, and PTH with femoral neck BMD. In conclusion, there is a slight decline in free testosterone and BMD in the healthy elderly males. However, sex male hormones are not correlated to the decrease in hip BMD. Other age-related factors must be associated with bone loss in elderly males. Received: 29 April 1997 / Accepted: 9 November 1997     

Effect of Aloe vera. on Rat Pulp Tissue

Abstract

Aloe vera. L. (Aloeaceae) has been extensively studied for anti-inflammatory, antimicrobial, and cellular regeneration properties. This work evaluated in vivo. the effects of powder of freeze-dried Aloe vera. on rat pulp tissue. Pulp tissue was mechanically exposed to Aloe vera., and it was evaluated at 1 to 30 days after the procedure by histopathologic examination. A predominant acute-moderate inflammatory infiltrate was observed in the Aloe vera.–treated group 1 to 7 days after treatment. At 14 to 30 days, pulp tissue took a normal pattern when comparing Aloe vera. treatment with the Ca(OH)₂ treatment; it was found that both treatment groups stimulated reparative dentin and the formation of complete bridge. Strong superficial necrosis was detected exclusively for Ca(OH)₂. It seems evident that application of Aloe vera. in direct contact with the exposed pulp has acceptable biocompatibility and can lead to tertiary bridge formation.     

Clonal origin of non-medullary thyroid tumours assessed by non-random X-chromosome inactivation.

OBJECTIVE: X-chromosome inactivation analysis was performed in order to assess the clonal origin of non-medullary thyroid tumours and to distinguish between multicentricity and multifocality in multiple papillary thyroid carcinoma (PTC). METHODS: One hundred and thirteen tumour samples from 31 patients with isolated PTC, 16 patients with multinodular PTC, 14 patients with follicular thyroid adenoma (FTA) and 15 patients with follicular thyroid carcinoma (FTC) were collected. The corresponding normal thyroid tissues were analysed, and in 14 cases, tumour-surrounding tissue was also studied. Genomic DNA was digested with HpaII and HhaI previous to PCR amplification of the polymorphic CAG repeat, on exon 1 of the human androgen receptor gene (HUMARA). PCR products were analysed by denaturing gel electrophoresis, silver staining and densitometric analysis. PCR products were also used to determine the number of CAG repeats of patients with isolated PTC, FTA, FTC and of 41 healthy volunteers. RESULTS: Heterozygosity for the HUMARA polymorphism was found in 64/76 (84%) cases. Lyonization of the thyroid was observed in 15/76 (20%) cases, which were excluded from clonal analysis. Except for two cases of isolated PTC, all tumour samples studied presented monoclonal X-inactivation patterns, while normal thyroid tissue was polyclonal. Monoclonal patterns were also found in 4/14 tumour-surrounding tissues. No difference was found in the length of CAG alleles between patients and controls. Of eight informative cases of multinodular PTC, three showed evidence of multicentricity and five revealed patterns consistent with multifocality. CONCLUSIONS: Both isolated and multinodular PTC as well as FTA and FTC are of monoclonal origin. Our results also suggest that approximately one-third of multiple PTC have an independent origin for the different nodules (multicentricity). Monoclonality was also found in tissues surrounding some PTC nodules. No association was found between the length of CAG alleles and thyroid malignancies.     

Evolution of weight and height of children with congenital heart disease undergoing surgical treatment

Objective

To evaluate the height and weight development of children with congenital heart disease undergoing surgery with the goal of determining when they reach the threshold of normal development and whether there are differences between patients with developmental pattern below the level of normality preoperatively (z-score<-2 for the analyzed parameter) in comparison to the total group of cardiac patients.

Methods

We prospectively followed up 27 children undergoing operation into five time periods: preoperatively and at four subsequent outpatient appointments: 1^st month, 3^rd month, 6^th month and 12^th month after hospital discharge. The anthropometric parameters used were median z-score (MZ), weight (WAZ), height (HAZ), subscapular skinfold (SSFAZ), upper arm circumference (UAC) and triceps skinfold (TSFAZ). The evolution assessment of the parameters was performed by analysis of variance and comparison with the general normal population from unpaired t test, both in the total group of cardiac patients, and in subgroups with preoperative parameters below the normal level (Zm<-2).

Results

In the total group there was no significant evolution of MZ of all parameters. WAZ was statistically lower than the normal population until the 1^st month of follow-up (P=0.028); HAZ only preoperatively (P=0.044), SSFAZ in the first month (P=0.015) and at 12^th month (P=0.038), UAC and TSFAZ were always statistically equal to the general population. In patients whose development was below the level of normality, there were important variation of WAZ (P=0.002), HAZ (P=0.001) and UAC (P=0.031) after the operation, and the WAZ was lower than the normal population until the 3^rd month (P=0.015); HAZ and UAC, until the first month (P=0.024 and P=0.039 respectively), SSFAZ, up to the 12^th month (P=0.005), the TSFAZ only preoperatively (P=0.011).

Conclusion

The operation promoted the return to normalcy for those with heart disease in general within up to three months, but for the group of patients below normal developmental pattern of the return occurred within 12 months.