Studies on the Influence of Ultraviolet Light on Initiation in Skin Tumorigenesis

The effect of shortwave ultraviolet (UV) light applied once or 10 times on initiation by 7, 12-dimethtybenz(a)anthracene (DMBA) in two-stage skin carcinogenesis was studied croton oil was used as promoter. The results showed that a single UV treatment increased the formation of benign tumors when given prior to initiation-promotion. The incidence of benign tumors decreased significantly when 10 doses of UV light were given after initiation, although a few carcinomas and sarcomas occurred, suggesting a summative effect of both agents

Longitudinal assessment of PCBs and chlorinated pesticides in pregnant women from Western Canada

BACKGROUND: Maternal exposures to organochlorines prior to pregnancy are considered a risk to neonatal welfare, specifically in relation to neurocognitive functions. There is growing interest in the evaluation of maternal blood testing as a marker for fetal exposure as well as the variable geographic distribution of these priority chemicals. METHODS: Three hundred and twenty-three women in the second trimester of pregnancy entered the study at a prenatal clinic providing genetic counselling information. Subjects who had an indication for genetic amniocentesis based on late maternal age were eligible to participate. Two hundred and thirty-eight completed an environmental questionnaire. A sample of amniotic fluid was taken for karyotype analysis in 323 women and blood samples during pregnancy (209), at birth (105) and from the umbilical cord (97) and breast milk (47) were also collected. These samples were tested for 29 PCB congeners and organochlorine pesticides. RESULTS: The concentrations of PCB 153 in these media were relatively low in relation to other studies. Σ PCBs measurements in samples taken during the second trimester of pregnancy, at birth and in the umbilical cord were strongly correlated. Specific measurements of PCB 153 and PCB 180 among those subjects with completed sampling of blood samples from mothers and cord samples were significantly correlated. The concentrations of PCBs and pesticides did not differ in relation to prior spontaneous abortion history. There were no organochlorines present in the amniotic fluid at the current level of quantification. CONCLUSION: Pregnant women from the Western Canada region of Calgary, Alberta are exposed to relatively low concentrations of organochlorines. Measurement of maternal blood during the second trimester of pregnancy can reliably estimate the fetal exposure to PCBs. This estimate is reliable for Group 2 and 3 PCBs as well as PCB 153 and PCB 180. The amniotic fluid does not contain measurable concentrations of pesticides and PCBs under the conditions of the levels of quantification

Physical function and self-rated health status as predictors of mortality: results from longitudinal analysis in the ilSIRENTE study

<p>Abstract</p> <p>Background</p> <p>Physical function measures have been shown to predict negative health-related events in older persons, including mortality. These markers of functioning may interact with the self-rated health (SRH) in the prediction of events. Aim of the present study is to compare the predictive value for mortality of measures of physical function and SRH status, and test their possible interactions.</p> <p>Methods</p> <p>Data are from 335 older persons aged ≥ 80 years (mean age 85.6 years) enrolled in the "Invecchiamento e Longevità nel Sirente" (<it>ilSIRENTE</it>) study. The predictive values for mortality of 4-meter walk test, Short Physical Performance Battery (SPPB), hand grip strength, Activities of Daily Living (ADL) scale, Instrumental ADL (IADL) scale, and a SRH scale were compared using proportional hazard models. Kaplan-Meier survival curves for mortality and Receiver Operating Characteristic (ROC) curve analyses were also computed to estimate the predictive value of the independent variables of interest for mortality (alone and in combination).</p> <p>Results</p> <p>During the 24-month follow-up (mean 1.8 years), 71 (21.2%) events occurred in the study sample. All the tested variables were able to significantly predict mortality. No significant interaction was reported between physical function measures and SRH. The SPPB score was the strongest predictor of overall mortality after adjustment for potential confounders (per SD increase; HR 0.64; 95%CI 0.48–0.86). A similar predictive value was showed by the SRH (per SD increase; HR 0.76; 95%CI 0.59–0.97). The chair stand test was the SPPB subtask showing the highest prognostic value.</p> <p>Conclusion</p> <p>All the tested measures are able to predict mortality with different extents, but strongest results were obtained from the SPPB and the SRH. The chair stand test may be as useful as the complete SPPB in estimating the mortality risk.</p

Pectin-coated titanium implants are well-tolerated in vivo

Multiform coated titanium implants are widely used in orthopedic and dental surgery. In this study, we have investigated the reactivity of pectin-coated titanium samples implanted under the latissimus dorsi—muscle fascia of rats. Samples were coated with two enzyme treated apple pectins; modified hairy regions (MHR-A and MHR-B) that differed in chemical structure. Aminated (AMI) and uncoated titanium (Ti) served as controls. The thicknesses of the peri-implant fibrous tissue capsules formed 1 or 3 weeks after implantation were measured as indicative of possible inflammatory reactions toward the biomaterials. After 1 week, the MHR-B implant was surrounded by a thicker fibrous capsule (42.9 µm) than any of the other sample types: MHR-A (33.2 µm), AMI (32.5 µm), and Ti (32.3 µm), the last one being the only statistically significant difference. After 3 weeks, however, this difference disappeared; the capsule thicknesses around MHR-B and Ti implants had decreased to the values found for AMI and MHR-A. Additionally, the capsule formation represents merely a stromal rather than an inflammatory reaction, as indicated by the absence of activated macrophages or foreign body giant cells in the capsules. These results indicate for the first time the in vivo tolerability of covalently linked pectins, and suggest the feasibility of pectin-coated bone and dental implants for clinical use