Expression profile of skin papillomas with high cancer risk displays a unique genetic signature that clusters with squamous cell carcinomas and predicts risk for malignant conversion

Chemical induction of squamous tumors in the mouse skin induces multiple benign papillomas: high-frequency terminally benign low-risk papillomas and low-frequency high-risk papillomas, the putative precursor lesions to squamous cell carcinoma (SCC). We have compared the gene expression profile of twenty different early low- and high-risk papillomas with normal skin and SCC. Unsupervised clustering of 514 differentially expressed genes (P<0.001) showed that 9/10 high-risk papillomas clustered with SCC, while 1/10 clustered with low-risk papillomas, and this correlated with keratin markers of tumor progression. Prediction analysis for microarrays (PAM) identified 87 genes that distinguished the two papilloma classes, and a majority of these had a similar expression pattern in both high-risk papillomas and SCC. Additional classifier algorithms generated a gene list that correctly classified unknown benign tumors as low- or high-risk concordant with promotion protocol and keratin profiling. Reduced expression of immune function genes characterized the high-risk papillomas and SCC. Immunohistochemistry confirmed reduced T-cell number in high-risk papillomas, suggesting that reduced adaptive immunity defines papillomas that progress to SCC. These results demonstrate that murine premalignant lesions can be segregated into subgroups by gene expression patterns that correlate with risk for malignant conversion, and suggest a paradigm for generating diagnostic biomarkers for human premalignant lesions with unknown individual risk for malignant conversion.

Knowledge and experiences of andropause among men in Lagos, Nigeria

BACKGROUND

Andropause is increasingly becoming a global health concern as the world's population of aging males increases.

OBJECTIVE

To describe the level of knowledge and experiences of as well as the responses of adult men to andropause in Lagos, Nigeria.

METHODS

Structured questionnaires were administered to 250 adult males selected by multistage sampling in Mushin area of Lagos, Nigeria.

RESULTS

Many of the respondents (45.1%) had no knowledge of andropause although most (96%) had experienced a wide variety of the characteristic physical changes. The main symptoms reported occurred mainly between the ages of 54-62 years. Increasing age, not working and lack of formal education were significantly associated with an increased number of a variety of symptoms experienced (p<0.001). Many of the respondents were indifferent about the symptoms they experienced, as they were accepted as a normal phase of the aging process.

CONCLUSION

Although there has been growing interest in andropause by health careproviders, pharmaceutical companies and the general public over the years, knowledge of its aetiology, diagnosis and management among black men is still incomplete. The findings of this study underscore the need for health education in order to increase the knowledge of and improve the quality of care of andropause among adult men in Nigeria.

Living anonymous liver donation: case report and ethical justification

Most living organ donations are from genetically or emotionally related donors. Although some transplant centers are willing to accept donations from living anonymous kidney donors (LAKDs), very few centers will accept donations from living anonymous liver donors (LALDs). The difference in acceptance rates is primarily due to the greater risk in liver donation, which is estimated to be 10-fold that of the risk in kidney donation. We present a case of donation from a LALD, the first reported in Canada. There are currently no established standards for LALDs. Our criteria for the ethical acceptability of LALDs require such donors to be physically healthy, mentally competent, altruistic, highly motivated, well-informed and able to give voluntary consent to donation. Another major ethical criterion is that the likely psychological benefit to the LALD balances the physical risks. Our case demonstrates that transplants from LALDs are medically successful and ethically justified under certain conditions.

Eating together is important: using a dining room in an acute elderly medical ward increases energy intake

AIM

To investigate the effect of eating in a supervised dining room, on nutritional intake and weight, for elderly patients on an acute medicine for the elderly ward.

METHOD

Patients on the intervention ward were encouraged to attend a dining room every lunch time by a trained nursing assistant as part of the rehabilitation process. The patients on the control ward ate only by their bedside. Food intake and weight data were collected over the study period on each patient.

RESULTS

Forty-eight patients participated in the study. At the lunch time meal studied the dining room group had higher intakes of energy compared with the controls [489 kcal (95% CI: 438-554) versus 360 kcal (95% CI: 289-448), P < 0.013]. There was no difference in protein intake between the groups [18.9 g (95% CI: 16.6-21.2) versus 17.7 g (95% CI: 13.2-22.2), P=0.63]. No significant difference in weight gain between the two groups was seen (P=0.6). However, there was a trend towards weight gain in the dining room group.

CONCLUSION

Food intake can be improved by using a supervised dining room, and this will potentially lead to weight gain and corresponding improvements in nutritional status and rehabilitation.

A fluorescence polarization assay for inhibitors of Hsp90

Hsp90 encodes a ubiquitous molecular chaperone protein conserved among species which acts on multiple substrates, many of which are important cell-signaling proteins. Inhibition of Hsp90 function has been promoted as a mechanism to degrade client proteins involved in tumorigenesis and disease progression. Several assays to monitor inhibition of Hsp90 function currently exist but are limited in their use for a drug discovery campaign. Using data from the crystal structure of an initial hit compound, we have developed a fluorescence polarization assay to monitor binding of compounds to the ATP-binding site of Hsp90. This assay is very robust (Z' > 0.9) and can detect affinity of compounds with IC50s to 40 nM. We have used this assay in conjunction with cocrystal structures of small molecules to drive a structure-based design program aimed at the discovery and optimization of a novel class of potent Hsp90 inhibitors.

Comparison of energy and protein intakes of older people consuming a texture modified diet with a normal hospital diet

BACKGROUND

There are very few studies looking at the energy and protein requirements of patients requiring texture modified diets. Dysphagia is the main indication for people to be recommended texture-modified diets. Older people post-stroke are the key group in the hospital setting who consume this type of diet. The diets can be of several consistencies ranging from pureed to soft textures.

OBJECTIVE

To compare the 24-hour dietary intake of older people consuming a texture modified diet in a clinical setting to older people consuming a normal hospital diet.

METHOD

Weighed food intakes and food record charts were used to quantify the patients' intakes, which were compared to their individual requirements.

RESULTS

The oral intake of 55 patients was measured. Twenty-five of the patients surveyed were eating a normal diet and acted as controls for 30 patients who were prescribed a texture-modified diet. The results showed that the texture-modified group had significantly lower intakes of energy (3877 versus 6115 kJ, P < 0.0001) and protein (40 versus 60 g, P < 0.003) compared to consumption of the normal diet. The energy and protein deficit from estimated requirements was significantly greater in the texture-modified group (2549 versus 357 kJ, P < 0.0001; 6 versus 22 g, P = 0.013; respectively).

CONCLUSION

These statistically significant results indicate that older people on texture-modified diets have a lower intake of energy and protein than those consuming a normal hospital diet and it is likely that other nutrients will be inadequate. All patients on texture-modified diets should be assessed by the dietitian for nutritional support. Evidence based strategies for improving overall nutrient intake should be identified.

Distance and movement time effects on the timing of agonist and antagonist muscles: a test of the impulse-timing theory

The experiment examined the effects of movement time (MT) and distance on the timing at electromyographic (EMG) activity from an agonist and antagonist muscle during rapid, discrete elbow movements in the horizontal plane. According to impulse-timing theory (Wallace, 1981) MT, not distance moved, should have a pronounced effect on the timing of EMG activity (duration of initial agonist and antagonist burst and time to onset of initial antagonist burst). The levels of MT were 100 and 160 msec and the levels of distance were 27 degrees and 45 degrees of elbow flexion. In general support of impulse-timing theory, the results of the three EMG timing measures showed that MT had a more pronounced effect on these measures than distance. In addition, the timing of EMG activity in relation to total MT remained fairly consistent across the four MT-distance conditions.

Effect of the introduction of helical CT on radiation dose in the investigation of pulmonary embolism

The aim of this study was to assess the change in patient radiation dose in the radiological investigation of pulmonary embolism since the introduction of helical CT pulmonary angiography (CTPA) in a large teaching hospital. All radiological investigations performed as an integral part of the imaging protocol in the investigation of clinically suspected pulmonary embolism (PE) were retrospectively reviewed. The protocol for the investigation of PE changed in our institution after the introduction of CTPA. Protocols 1 and 2 were the protocols in place before and after the introduction of CTPA, respectively. An in-depth evaluation was made of the imaging records and radiation dose for 30 consecutive patients investigated for clinically suspected PE in 1995 (protocol 1) and 2002 (protocol 2). Radiation doses were then extrapolated for the total number of patients investigated in each year. The number of radiological investigations performed per patient decreased from a mean of 1.17 in protocol 1 to 1.06 in protocol 2. There was a 44% increase in the total number of patients investigated. The effective dose per patient increased from 1.30 mSv to 1.35 mSv with the introduction of CTPA into the imaging protocol, an increase of only 4%. First line investigations showed a significant decrease in indeterminate examinations from 25.7% to 8.5%. Two different imaging protocols are reviewed with respect to type and number of procedures required for the investigation of PE and the resulting patient effective dose incurred. Results demonstrate an increase in the number of patients being investigated for suspected PE and a small increase in effective dose per patient since the introduction of helical CTPA. Although CTPA in itself incurs a higher effective dose, this is offset by the significant decrease in the number of non-diagnostic and total number of investigations per patient. In addition the ventilation component of lung scintigraphy was not required in protocol 2, thus reducing the dose further. We believe this small increase in effective dose is justified by the decrease in non-diagnostic studies and the reduction in total number of investigations per patient. We hope this paper will serve as a stimulus for the radiology community to examine current protocols in all areas of diagnostic imaging. We stress the importance of assessing new and established imaging investigative protocols to maximize the benefit and reduce any risk to patients.

Helical CTPA in the investigation of pulmonary embolism: a 6-year review

AIM

To assess the change in practice and resulting diagnostic outcome in the radiological investigation of pulmonary embolism (PE) since the introduction of helical CTPA in a large teaching hospital.

MATERIALS AND METHODS

A retrospective review was undertaken of all radiological investigations performed over a 6-year period before and after the introduction of CTPA (protocols 1 and 2, respectively) as an integral part of the imaging protocol in the investigation of clinically suspected PE. The total numbers and results of all investigations are assessed for each protocol.

RESULTS

A substantial increase in both the total number of patients and the number of investigations performed for the investigation of PE since the introduction of CTPA occurred. Five hundred and twenty-six patients underwent 617 investigations in 1995-1996, and 760 patients underwent 805 investigations in 2001-2002. There was a significant decrease in the number of investigations per patient, 1.17 in 1995-1996 versus 1.06 in 2001-2002. Primary investigation showed a significant decrease in indeterminate examinations from 25.7 to 8.5% and an increase in positive results for PE from 18 to 24%.

CONCLUSION

In the study population there was a significant increase in the number of patients being investigated for PE, with a decrease in both the number of non-diagnostic investigations and the total investigations per patient since the introduction of helical CTPA. This is probably due to the ready availability of a new imaging technique and physicians awareness that CTPA has significantly improved specificity, which encourages the referral of patients for investigation.

Pharmacokinetic-pharmacodynamic interaction between BIA 3-202, a novel COMT inhibitor, and levodopa/carbidopa

This study investigated the tolerability and the pharmacokinetic and pharmacodynamic interactions between single oral administration of BIA 3-202 (50 mg, 100 mg, 200 mg, and 400 mg), a novel catechol-O-methyltransferase (COMT) inhibitor, and standard carbidopa/levodopa 25 mg/100 mg (Sinemet 25/100) in healthy adult volunteers. This was a single-center, double-blind, placebo-controlled, randomized, crossover study with 5 single-dose treatment periods with a washout period of 2 weeks between doses. During each treatment period, a different dose of BIA 3-202 or placebo was administered concomitantly with Sinemet 25/100. Tolerability was assessed by recording adverse events, vital signs, continuous EKG, and clinical laboratory parameters. Pharmacokinetic parameters of levodopa and 3-O-methyl-levodopa (3-OMD) were determined. The activity of soluble COMT in erythrocytes was also measured. Eighteen subjects (10 men and 8 women) participated in the study. The drug combination was well tolerated, with the adverse events reported being transient and generally mild in severity. Mean levodopa Cmax values were attained at 0.8 to 1.8 hours postdose. Thereafter, plasma levodopa levels declined with a mean t1/2 that increased in a manner that depended on the dose of BIA 3-202. The increase in systemic exposure to levodopa (AUC0-infinity) occurred at all doses of BIA 3-202, attaining its maximum at 200 mg BIA 3-202 (95% conficence interval, 1.43-1.73). The mean Cmax and AUC0-infinity values of 3-OMD decreased dose proportionally in BIA 3-202-treated subjects, with differences being statistically significant for all the doses tested. Maximum COMT inhibition occurred between 0.8 and 2.0 hours postdose, and ranged from 56 (50 mg) to 85% (400 mg). Time to return to baseline COMT activity ranged from 6 (50 mg) to 18 hours (400 mg), following the same dose-dependent tendency. In conclusion, the novel COMT inhibitor BIA 3-202 increased the bioavailability of levodopa and reduced the formation of 3-OMD when administered with standard levodopa/carbidopa.

Expression of human decay accelerating factor or membrane cofactor protein genes on mouse cells inhibits lysis by human complement

Mouse cells expressing the human complement regulatory proteins decay accelerating factor (DAF) or membrane cofactor protein (MCP) were produced both by hybridoma technology and by transfection with the appropriate cDNAs. The expression of either or both of these products protected the mouse cell from lysis by human (though not rabbit) complement in the presence of naturally occurring human anti-mouse antibody. This effect could be abrogated by the addition of monoclonal antibody against DAF or MCP. These data suggested that the production of animals transgenic for human complement regulatory proteins should in principle be similarly protected from hyperacute xenograft rejection.

Pharmacokinetic-pharmacodynamic interaction between BIA 3-202, a novel COMT inhibitor, and levodopa/benserazide

BIA 3-202 is a novel catechol-O-methyltransferase (COMT) inhibitor being developed for use as a levodopa-sparing agent in Parkinson's disease. This study investigated the effect of four single oral doses of BIA 3-202 (50 mg, 100 mg, 200 mg, and 400 mg) compared with placebo on plasma concentrations of levodopa and its metabolite 3- O-methyl-levodopa (3-OMD) and on inhibition of erythrocyte COMT in healthy subjects receiving 100 mg of levodopa and 25 mg of benserazide (Madopar 125). This was a single-centre, double-blind, placebo-controlled, randomised, crossover study with five single-dose treatment periods. The washout period between doses was 2 weeks. On each treatment period, a different dose of BIA 3-202 or placebo was administered concomitantly with Madopar 125. Tolerability was assessed by recording adverse events, vital signs, continuous electrocardiogram and clinical laboratory parameters. In the study, 18 subjects (12 male and 6 female) participated. The drug combination was well tolerated. All doses of BIA 3-202 significantly increased the area under the concentration-time curve (AUC) versus placebo, ranging from 39% (95% confidence intervals, 1.06-1.69) with 50 mg to 80% (95% confidence intervals, 1.42-2.22) with 400 mg. No significant change in mean maximum plasma concentrations (C(max)) of levodopa was found. Mean C(max) and AUC of 3-OMD significantly decreased for all doses tested. BIA 3-202 caused a rapid and reversible inhibition of S-COMT activity, ranging from 57% (50 mg) to 84% (400 mg). In conclusion, the novel COMT inhibitor BIA 3-202 was well tolerated and significantly increased the bioavailability of levodopa and reduced the formation of 3-OMD when administered with standard release levodopa/benserazide.