Supercritical fluid processing of drug nanoparticles in stable suspension

Significant effort has been directed toward the development of drug formulation and delivery techniques, especially for the drug of no or poor aqueous solubility. Among various strategies to address the solubility issue, the reduction of drug particle sizes to the nanoscale has been identified as a potentially effective and broadly applicable approach. Complementary to traditional methods, supercritical fluid techniques have found unique applications in the production and processing of drug particles. Here we report the application of a newly developed supercritical fluid processing technique, Rapid Expansion of a Supercritical Solution into a Liquid Solvent, to the nanosizing of potent antiparasitic drug Amphotericin B particles. A supercritical carbon dioxide-cosolvent system was used for the solubilization and processing of the drug. The process produced well-dispersed nanoscale Amphotericin B particles suspended in an aqueous solution, and the suspension was intrinsically stable or could be further stabilized in the presence of water-soluble polymers. The properties of the drug nanoparticles were found to be dependent on the type of cosolvent used. The results on the use of dimethyl sulfoxide and methanol as cosolvents and their effects on the properties of nanosized Amphotericin B particles are presented and discussed.

Simple rationality? The law of healthcare resource allocation in England

This paper examines the law relating to healthcare resource allocation in England. The National Health Service (NHS) Act 1977 does not impose an absolute duty to provide specified healthcare services. The courts will only interfere with a resource allocation decision made by an NHS body if that decision is frankly irrational (or where the decision infringes the principle of proportionality when a right under the European Convention on Human Rights (ECHR) is engaged). Such irrationality is very difficult to establish. The ECHR has made no significant contribution to domestic English law in the arena of healthcare provision. The decision of the European Court in the Yvonne Watts case establishes that, in relation to the question of entitlement to seek treatment abroad at the expense of the NHS, a clinical judgment about the urgency of treatment trumps an administrative decision about waiting list targets. That decision goes against the grain of domestic law about healthcare allocation, but is not likely to have wide ramifications in domestic law.

Safety of neoadjuvant oxaliplatin-based chemotherapy (N-FOLFOX) in patients undergoing resection of colorectal liver metastases (R-CLM). Interim results

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Background: Oxaliplatin-5-fluorouracil-leucovorin (FOLFOX) has significant activity against CRC in both the metastatic and adjuvant settings. Consequently, neoadjuvant FOLFOX (N-FOLFOX) is being investigated in R-CLM. This has raised concerns regarding the safety and rate of post-operative complications (P-OCs) with N-FOLFOX, specifically, development of sinusoidal dilatation (SD), fibrosis and steatosis. This single-center cohort study was conducted to prospectively evaluate safety of N-FOLFOX in R-CLM patients. Methods: Planned total sample size is 40 patients [20 N-FOLFOX; 20 no chemotherapy (N-C)]. The N-C group consists of patients undergoing surgery for other hepatic pathology. Normal liver was examined by light (LM) and electron (EM) microscopy for SD, perisinusoidal fibrosis, and steatosis/necrosis; severity was graded from 0 (absent) to 2. The rate of P-OCs, hospital stays, and liver function tests (LFTs) were assessed. Results: At the time of this analysis, 20 patients (10 N-FOLFOX; 10 N-C) have undergone surgery. In the N- FOLFOX group, median number of cycles of N-FOLFOX was 6, with 2 patients receiving only 4 cycles. The median time between completion of N-FOLFOX and surgery was 6 weeks. There were no statistical differences between N-FOLFOX and N-C groups in potentially confounding factors, including previous chemotherapy, alcohol consumption, medical history, or concomitant medications. Number of patients with SD was 8 in each group (all were grade 1 except for 1 patient in N-C who had grade 2). Steatosis was seen in 7 and 6 patients in N-FOLFOX, and N-C groups, respectively (2 patients in each group were grade 2; remaining were grade 1). Fibrosis was noted in only 1 patient in N-C group. No nodular regeneration was observed in either group. There was a subjective loss on EM of mitochondria and Golgi apparatus/body with N-FOLFOX. Median post-operative hospital stay was 12 days in both groups. Conclusions: N-FOLFOX appears to have no clinically significant deleterious effects on normal liver architecture, function, or recovery post-surgery in R-CLM patients. The study is ongoing to accrue up to 40 patients; updated data will be presented.

No significant financial relationships to disclose.

The I allele of the ACE gene is associated with improved exercise capacity in women with McArdle disease

BACKGROUND

McArdle disease is an uncommon metabolic disorder usually characterized by marked exercise intolerance although great individual variability exists in its phenotypic manifestation.

OBJECTIVE

The purpose of this study was to determine the association between angiotensin-converting enzyme (ACE) genotypes and indices of exercise capacity (peak oxygen uptake (VO(2)peak), ventilatory threshold (VT) and gross mechanical efficiency (GE)) in patients with McArdle disease. Based on previous research, it was hypothesized that the I allele might favourably influence exercise capacity.

METHODS

Forty-four Spanish patients (23 males, 21 females) and 44 age-matched and gender-matched controls (23 males, 21 females) performed a graded cycle-ergometer test until exhaustion (for VO(2)peak and VT determination) and a 12 min constant-load test at the power output eliciting the VT (for GE determination).

RESULTS

No significant difference (p>0.05) was found in indices of exercise capacity between ID + II genotypes and DD homozygotes in the group of male patients, male controls and female controls. However, in the group of female patients, the ID + II group (n = 11) had a higher VO(2)peak than DD homozygotes (n = 10) (15.8 (SEM 1.6) ml/kg/min versus 11.9 (SEM 0.9) ml/kg/min, respectively; p<0.05).

CONCLUSIONS

The I allele of the ACE gene is associated with a higher functional capacity in female patients, and might partly explain the individual variability in the phenotypic manifestation of McArdle disease.

Early withdrawal of calcineurin inhibitors and rescue immunosuppression with sirolimus-based therapy in renal transplant recipients with moderate to severe renal dysfunction

Mammalian Target-of-Rapamycin inhibitors (mTOR inhibitors) can be used to replace the calcineurin inhibitors (CNIs) to prevent progression in chronic kidney disease (CKD) following organ transplantation. Discontinuation of tacrolimus in 136 recipients of kidney transplants with progressive renal dysfunction significantly decreased the rate of loss of estimated glomerular filtration rate (eGFR, mL/min/1.73 m(2)) (pre-intervention vs. post-intervention slopes, -0.013 vs. -0.002, p < 0.0001). Discontinuation of tacrolimus was associated with a sustained and significant improvement in graft function (pre-eGFR vs. post-eGFR; 26.0 +/- 1.1 vs. 47.4 +/- 2.1, p < 0.0001) in 74% of patients. This intervention was ineffective if the mean and (median) values of creatinine (mg/dL) and eGFR were 3.8 +/- 0.2 (3.4) and 18.4 +/- 1.9 (22.4), respectively, at the time of conversion therapy. During the follow-up (range, 1.5-34.6, months), a total of 13 patients had their first acute rejection following the conversion therapy, an annual incidence of less than 10% and none of these episodes resulted in graft loss. The salutary effects of sirolimus therapy following discontinuation of tacrolimus in patients with moderate to severe graft dysfunction due to allograft nephropathy even in high-risk patients improves kidney function and prevents acute rejection.

Disclosure of genetics research results after the death of the patient participant: a qualitative study of the impact on relatives

When a gene mutation is identified in a research study following the death of the study participant, it is not clear whether such information should be made available to relatives. We report here an evaluation of the impact on relatives of being informed of study results that detected pathogenic BRCA2 mutations in a male relative, now deceased, who had early onset (under the age of 55) prostate cancer. The breast and ovarian cancer risk was unknown to the living relatives. Qualitative analysis of interviews with thirteen relatives indicated that those who had a higher risk perception, resulting from an awareness of cancer family history or experiential knowledge of cancer in their family, tended to adjust more easily to the results. All participants believed that genetics research results of clinical significance should be fed back to relatives. Those who were fully aware of the BRCA2 results and implications for themselves felt they had benefited from the information, irrespective of whether or not they had elected for genetic testing, because of the consequent availability of surveillance programs. Initial anxiety upon learning about the BRCA2 result was alleviated by genetic counselling. Factors influencing those who have not engaged with the information included scepticism related to the relative who attempted to inform them, young age and fear of cancer. Those who had not sought genetic counselling did not attempt further dissemination, and some were not undergoing regular screening. Implications for informed consent in genetics research programs, and the requirement for genetic counselling when research results are disclosed, are discussed.

Predictive genetic testing for BRCA1/2 in a UK clinical cohort: three-year follow-up

This prospective multicentre study assesses long-term impact of genetic testing for breast/ovarian cancer predisposition in a clinical cohort. Areas evaluated include risk management, distress and insurance problems 3 years post-testing. Participants are adults unaffected with cancer from families with a known BRCA1/2 mutation. One hundred and ninety-three out of 285 (70% response) participants at nine UK clinical genetics centres completed assessments at 3 years: 80% female; 37% carriers of a BRCA1/2 mutation. In the 3 years, post-genetic testing carriers reported more risk management activities than non-carriers. Fifty-five per cent of female carriers opted for risk reducing surgery; 43% oophorectomy; and 34% mastectomy. Eighty-nine per cent had mammograms compared with 47% non-carriers. Thirty-six per cent non-carriers > or =50 years did not have a mammogram post-test. Twenty-two per cent male carriers had colorectal and 44% prostate screening compared with 5 and 19% non-carriers respectively. Seven per cent carriers and 1% non-carriers developed cancer. Distress levels did not differ in carriers and non-carriers at 3-year follow-up. Forty per cent of female carriers reported difficulties with life and/or health insurance. Given the return to pre-test levels of concern among female non-carriers at 3 years and a substantial minority not engaging in recommended screening, there appears to be a need to help some women understand the meaning of their genetic status.

The research priorities of patients attending UK cancer treatment centres: findings from a modified nominal group study

Members of the public are increasingly consulted over health care and research priorities. Patient involvement in determining cancer research priorities, however, has remained underdeveloped. This paper presents the findings of the first consultation to be conducted with UK cancer patients concerning research priorities. The study adopted a participatory approach using a collaborative model that sought joint ownership of the study with people affected by cancer. An exploratory, qualitative approach was used. Consultation groups were the main method, combining focus group and nominal group techniques. Seventeen groups were held with a total of 105 patients broadly representative of the UK cancer population. Fifteen areas for research were identified. Top priority areas included the impact cancer has on life, how to live with cancer and related support issues; risk factors and causes of cancer; early detection and prevention. Although biological and treatment related aspects of science were identified as important, patients rated the management of practical, social and emotional issues as a higher priority. There is a mismatch between the research priorities identified by participants and the current UK research portfolio. Current research activity should be broadened to reflect the priorities of people affected by the disease.

Exposure-Efficacy Relationships of a Fingolimod-Everolimus Regimen in Kidney Transplant Patients at Risk for Delayed Graft Function

OBJECTIVE

We explored relationships between blood levels of fingolimod (FTY720) and everolimus versus treated biopsy-proven acute rejection (BPAR) in an open-label trial in de novo kidney transplant recipients.

METHODS

Patients (n = 52) who fulfilled predefined criteria placing them at increased risk of delayed graft function received fingolimod 2.5 mg/d, everolimus 2 mg twice daily with trough blood levels (C0) adjusted to 4 to 8 ng/mL, and corticosteroids. Everolimus and fingolimod C0 were collected over 1 year; efficacy readout was at 3 months.

RESULTS

Fingolimod C0 accumulated over the first 3 months with a time-averaged level (C0avg) of 5.7 +/- 3.5 ng/mL. At steady state in months 3 to 12, C0 was 7.0 +/- 4.4 ng/mL. Overall, 30 patients (58%) were free from BPAR to month 3. Patients were divided into four groups based on whether their fingolimod C0avg and everolimus C0avg were above or below the population medians. Freedom from BPAR was 53% and 57% for low fingolimod combined with low and high everolimus, whereas the percentages were improved to 83% and 85% for high fingolimod combined with low and high everolimus.

CONCLUSIONS

This pilot study with an everolimus-fingolimod regimen demonstrated trends in freedom from rejection that were drug concentration-related and that underscored, in particular, a strong contribution to efficacy from fingolimod.

Will clinical guidelines replace judges?

Medicine is increasingly a science and decreasingly an art. It is increasingly evidence-based. It now has right answers and wrong answers in a way inconceivable even a decade ago. The growth of evidence-based medicine is partly a consequence of genuine demonstration of optimal practice, and partly a consequence of increased dissemination of information. The natural consequence of the growth of evidence-based medicine is that clinical judgment is increasingly circumscribed by clinical guidelines. Clinical guidelines generally aspire to embody the local, national or international consensus emerging from the literature--but that consensus may be modified in the guideline to take account of local clinical, logistical and economic considerations. This paper looks at the effect that the guidelines revolution has had and will have on the way that clinical negligence litigation is conducted in England.

Combined aerobic and resistance training in breast cancer survivors: A randomized, controlled pilot trial

The purpose of this pilot study was to examine the effects of a combined cardiorespiratory and resistance exercise training program of short duration on the cardiorespiratory fitness, strength endurance, task specific functional muscle capacity, body composition and quality of life (QOL) in women breast cancer survivors. Sixteen subjects were randomly assigned to either a training (n = 8; age: 50 +/- 5 yrs) or control non-exercising group (n = 8; age: 51 +/- 10 yrs). The training group followed an 8-week exercise program consisting of 3 weekly sessions of 90-min duration, supervised by an experienced investigator and divided into resistance exercises and aerobic training. Before and after the intervention period, all of the subjects performed a cardiorespiratory test to measure peak oxygen uptake (VO2peak), a dynamic strength endurance test (maximum number of repetitions for chest and leg press exercise at 30 - 35 % and 100 - 110 % of body mass, respectively) and a sit-stand test. Quality of life was assessed using the European Organization for Research and Treatment of Cancer QLQ-C30 (EORTC-C30) questionnaire. In response to training, QOL, VO2peak (mean 3.9 ml/kg/min; 95 % CI, 0.93, 6.90) performance in leg press (17.9 kg; 95 % CI, 12.8, 22.4) and sit-stand test (- 0.67 s; 95 % CI, - 0.52, - 1.2) improved (p < or = 0.05). We observed no significant changes in the control group. Combined cardiorespiratory and resistance training, even of very brief duration, improves the QOL and the overall physical fitness of women breast cancer survivors.

Effects of detraining on the functional capacity of previously trained breast cancer survivors

The purpose of this study was to assess the effects of a relatively short (8-weeks) period of detraining on cardiorespiratory capacity, dynamic strength endurance, task specific functional muscle capacity and quality of life (QOL) of breast cancer survivors who had previously undergone a combined supervised (aerobic and resistance) training program. Eleven women survivors of stage I - II ductal breast carcinoma (47 +/- 7 yrs) entered the study and performed a battery of tests (including anthropometric evaluation, a graded cycle ergometer test, tests of strength endurance [leg and bench press] and the sit-stand test) and completed a specific QOL questionnaire (EORTC-C30) at three time points: i) before, ii) after an exercise program (including aerobic and resistance exercises) of 8-weeks duration, and iii) after a subsequent 8-weeks period of training cessation. Training-induced improvements in strength endurance, muscle functional capacity (sit-stand test) and QOL were not significantly changed after detraining (p > 0.05 for post-training vs. detraining comparisons). The lack of significant loss in muscle strength endurance occurred despite significant losses in estimated total muscle mass after detraining (27.3 +/- 2.4 kg) compared with post-training (28.5 +/- 2.9 kg). In contrast, cardiorespiratory capacity was significantly decreased during detraining (V.O (2peak) of 29.0 +/- 4.6 vs. 22.7 +/- 3.9 ml . kg ( -1) . min (-1) at post-training vs. detraining, p < 0.01). In conclusion, cancer survivors who have participated in a combined training program can retain some of the training gains (particularly improved QOL and muscle strength endurance/functional performance) after a relatively short duration detraining period.

The relationship between access and quality of urban green space with population physical activity

OBJECTIVES

This study examined the association between access to quality urban green space and levels of physical activity.

STUDY DESIGN

A cross-sectional examination of the relationship between access to quality urban green space and level of recreational physical activity in 4950 middle-aged (40-70 years) respondents from the European Prospective Investigation into Cancer and Nutrition (EPIC), who resided in Norwich, UK.

METHODS

Using geographic information systems (GIS), three measures of access to open green space were calculated based on distance only, distance and size of green space and distance, size and quality of green space. Multiple regression models were used to determine the relationship between the three indicators of access to open green space and level of recreational physical activity.

RESULTS

There was no evidence of clear relationships between recreational activity and access to green spaces. Non-significant associations were apparent for all variables, and there was no evidence of a clear trend in regression coefficients across quartiles of access for either the distance, size adjusted, and quality and size-adjusted models. Furthermore, the neighbourhood measures of access to green spaces showed non-significant associations with recreational physical activity.

CONCLUSIONS

Access to urban green spaces does not appear to be associated with population levels of recreational physical activity in our sample of middle-aged adults.

Exercise capacity in a 78 year old patient with McArdle's disease: it is never too late to start exercising

The case is reported of a 78 year old man with McArdle's disease and a history of treated coronary heart disease. Despite the pre-exercise administration of sucrose allowing the patient to exercise with normal physiological responses, and without typical McArdle's symptoms or biochemical evidence of muscle damage, his exercise capacity was very low (V(O2)peak = 10.7 ml/min/kg), probably attributable to his lifetime of sedentary living. The data suggest that, with pre-exercise sucrose administration, such patients may be candidates for systematic reconditioning, which may improve functional capacity and quality of life.

Mobilisation of mesenchymal cells into blood in response to skeletal muscle injury

Mesenchymal cells recruited to damaged tissues must circulate through the bloodstream. The absolute numbers of circulating mesenchymal stem cells (cMSCs) in two different models of acute and chronic skeletal muscle injury were determined. cMSCs were present in significantly higher numbers in both models than in healthy controls. These results support the hypothesis that MSCs are mobilised into the bloodstream after skeletal muscle tissue damage. These two models (acute and chronic) would be of value in the search for molecular mediators of mobilisation of MSCs into the circulation.

ACTN3 Genotype in Professional Endurance Cyclists

The Z-disk protein alpha-actinin-3 is only expressed in type II muscle fibres, which are responsible for generating forceful contractions at high velocity. Despite the evolutionary conservation of alpha-actinin-3, approximately one in every five Caucasians of European ancestry is totally deficient in this protein, due to homozygosity for a R577X polymorphism in the ACTN3 gene. This, together with the results of recent research on elite athletes, suggests that the "null" XX polymorphism might confer some advantage to endurance performance events. To test this hypothesis, we studied the frequency distribution of R577X genotypes in a group of 50 top-level male professional cyclists (26.9 +/- 0.4 yrs [mean +/- SEM]; VO2max: 73.5 +/- 0.8 ml x kg (-1) x min (-1)). Their results were compared with those of a group of 52 Olympic-class male endurance runners (26.8 +/- 0.6 yrs; VO2max: 73.3 +/- 0.8 ml x kg (-1) x min (-1)) and 123 healthy, sedentary male controls. All subjects were Caucasian, and of European ancestry. No significant differences (p > 0.05) were found between groups: RR: 28.5 %; RX: 53.6 % and XX: 17.9 % in controls; RR: 28.0 %; RX: 46.0 % and XX: 26.0 % in cyclists; and RR: 25.0 %; RX: 57.7 %; XX: 17.3 % in runners). No differences were found in indices of endurance performance (VO2peak or ventilatory thresholds) between athlete carriers of each R577X genotype. In summary, although the alpha-actinin-3 deficient XX genotype may be detrimental for sprint performance in humans, the R577X polymorphism of the ACTN3 gene does not appear to confer an advantage on the ability of male athletes to sustain extreme endurance performance.

Submissions from non-existent claimants: the non-identity problem and the law

Some medical interventions (or indeed omissions) determine the identity of a person. Those interventions or omissions may themselves cause harm, for which a child subsequently sues. Even if they do not themselves cause harm they may result in the birth of a child who subsequently brings a claim for being allowed to exist in the state caused by the intervention. The obvious objection to a claim of either class is that in the absence of the medical intervention or omission of which the claimant complains, the claimant would never have existed at all. This objection arises from what philosophers have called the "non-identity problem". This article examines the attitude that the English courts would be likely to have to such a claim. It concludes that the English law has so far failed to appreciate the significance of the non-identity problem, but will have to grapple with it soon.

Validity and reliability of the session RPE method for monitoring exercise training intensity

Objective. The Session Rating of Perceived Extertion (RPE) is a method of measuring exercise intensity that may be useful for the quantitative assessment of exercise training programmes. However, there are inadequate data regarding the validity and reliability of the Session RPE method. This study was designed to evaluate both the validity and reliability of the Session RPE method in comparison to objective measures (%HRpeak, %HRreserve and %VO2peak) of exercise intensity. Methods. Fourteen healthy volunteers (7 male, 7 female) performed 6 randomly ordered 30-minute constant-load exercise bouts at 3 different intensities, with each intensity being repeated. Oxygen consumption (VO2) and heart rate (HR) were measured throughout each exercise bout and normalised to maximal values obtained during a preliminary maximal exercise test. Thirty minutes following the conclusion of each exercise bout, the subject rated the global intensity of the bout using a modification of the Category Ratio (CR) (0 - 10) RPE scale. This rating was compared to the mean value of objectively measured exercise intensity across the duration of the bout. Results. There were significant non-linear relationships between Session RPE and %VO2peak (R2 = 0.76), %HRpeak (R2 = 0.74) and %HRreserve (R2 = 0.71). There were no significant differences between test and retest values of %VO2peak, %HRpeak, %HRreserve and Session RPE during the easy (47 v. 47%, 65 v. 66%, 47 v. 48% and 2.0 v. 1.9), moderate (69 v. 70%, 83 v. 84%, 74 v. 75%, and 4.2 v. 4.3) and hard (81 v. 81%, 94 v. 94%, 91 v. 91% and 7.3 v. 7.4) exercise bouts. Correlations between repeated bouts for %VO2peak (r = 0.98), %HRpeak (r = 0.98), %HRreserve (r = 0.98) and Session RPE (r = 0.88) were significant and strong. Conclusions. The results support the validity and reliability of the Session RPE method of monitoring exercise intensity, although as might be predicted for a subjective method the Session RPE was less precise than the objective measures of exercise training intensity. South African Journal of Sports Medicine Vol. 18 (1) 2006: pp. 14-17

Men's decision-making about predictive BRCA1/2 testing: the role of family

Men who have a family history of breast and/or ovarian cancer may be offered a predictive genetic test to determine whether or not they carry the family specific BRCA1/2 mutation. Male carriers may be at increased risk of breast and prostate cancers. Relatively little is known about at-risk men's decision-making about BRCA1/2 testing. This qualitative study explores the influences on male patients' genetic test decisions. Twenty-nine in-depth interviews were undertaken with both carrier and noncarrier men and immediate family members (17 male patients, 8 female partners, and 4 adult children). These explored family members' experiences of cancer and genetic testing, decision-making about testing, family support, communication of test results within the family, risk perception and risk management. Implicit influences on men's testing decisions such as familial obligations are examined. The extent to which other family members--partners and adult children--were involved in testing decisions is also described. It is demonstrated that mothers of potential mutation carriers not only perceive themselves as having a right to be involved in making this decision, but also were perceived by their male partners as having a legitimate role to play in decision-making. There was evidence that (adult) children were excluded from the decision-making, and some expressed resentment about this. The implications of these findings for the practice of genetic counseling are discussed.

Communication about genetic testing in families of male BRCA1/2 carriers and non-carriers: patterns, priorities and problems

This qualitative interview study explored the way in which information about predictive BRCA1/2 testing and its implications for children is disseminated within the families of at-risk men who undergo genetic testing. Twenty-nine in-depth interviews were carried out with family members [male patients (n = 17), their partners (n = 8) and adult children (n = 4)]. These explored the following themes: experiences of cancer and genetic testing, decision-making about testing and the communication of test results and genetic information within the immediate family. The interviews revealed that both male patients and their partners perceive themselves, rather than health professionals, as responsible for disclosing information about genetic testing and genetic risks to their children. Parents described three different communication strategies for the disclosure of genetic information to their children: complete openness, limited disclosure and total secrecy. The adoption of a particular communication strategy was justified in terms of children's rights to information vs their parental duties to protect their children from anxiety-provoking information. Some of the problems arising from the adoption of different disclosure patterns are identified and the implications for clinical practice are discussed.