Experience and Impact of a Locally-Based Peer, Volunteer Cancer Support Programme in Hospital Melaka, Melaka Malaysia

Background: Melaka is a small southern state in Peninsular Malaysia. On average, the state has an annual incidence of 200 odd breast cancer patients, largely treated out of its public, subsidized, single tertiary treatment center of Hospital Melaka. Hospital Melaka is an 800-bedded hospital with multiple specialties including surgery and radiology. Though the hospital does not have a dedicated oncology department, cancer treatment is carried out via phone consultations and visiting oncologists as well as a team of on-site nursing staff who are trained to initiate and monitor treatment. Feedback from Hospital Melaka staff highlighted that there was a drop-out rate of about 30% of patients from the treatment journey. Qualitative interviews with different stakeholders including patient revealed that the drop-out may be driven by factors such as: i) fear of surgery, ii) fear of chemotherapy, iii) fear of disfigurement, iv) loss of spouse v) emotional distress and shock; and vi) delay in waiting times for different levels of diagnostics and treatment. Aim: The aim of the initiative was to reduce the rate of patients who defaulted out from the cancer treatment journey via a three-pronged approach: a) improving understanding about cancer and treatment by patients and family members; b) integrating peer-support into the clinical treatment pathway at the hospital and reduction of waiting times; and c) maintaining a continuous interaction with the patient throughout the treatment journey. Methods: The inception and deployment of a locally-based peer, volunteer support program for breast cancer patients and families as part of the formal cancer treatment process in Hospital Melaka. Volunteers were consisted of a trained mix of cancer survivors, current and retired healthcare practitioners and provided information pertaining to treatment and care aspects of breast cancer as well as emotional support and follow-up of patients via phone or in person to ensure compliance to treatment. In this study, we engaged with various stakeholders including hospital management and clinicians. Then, support group's services were formalized into the care pathway for all patients with breast cancer; with both volunteers able to send and receive patient referrals. Results: Statistically significant reductions in patient delays in decision-making to seek treatment as well as a significant decrease of 12.5% in the number of defaulters. Conclusion: A support program built with support from all stakeholders and run by volunteers and embedded within the formal care process acts as a catalyst to enhance both service delivery as well as keeping patients engaged on the cancer care journey.

Comparative Analysis of Non-viral Transfection Methods in Mouse Embryonic Fibroblast Cells

Mouse embryonic fibroblast (MEF) cells are an important in vitro model for developmental biology, disease, and reprogramming studies. However, as with other primary cells, they are challenging to transfect. Although viral gene-delivery methods achieve high gene-delivery efficiency, challenges with cell mutagenesis and safety among others have led to the use and improvement of non-viral gene-delivery methods in MEF cells. Despite the importance of gene delivery in MEF cells, there is limited comparison of method/reagent efficacy. In this study, we compared the effectiveness of different gene-delivery methods and several reagents currently available in MEF cells by introducing a plasmid containing enhanced green fluorescent protein (EGFP). We analyze transfection efficiency by EGFP fluorescence. Our results suggest that two gene-delivery methods-electroporation and magnetofection in combination with a lipid reagent, are the most efficient transfection methods in MEF cells. This study provides a foundation for the selection of transfection methods or reagents when using MEF cells.

MSC-seeded dense collagen scaffolds with a bolus dose of VEGF promote healing of large bone defects

The functional repair of large skeletal defects remains a significant challenge to orthopaedic surgeons due to the lack of effective strategies to promote bone regeneration, particularly in the elderly. This study investigated the potential use of bone marrow derived mesenchymal stromal cells (MSC) in a dense collagen scaffold with a bolus dose of vascular endothelial growth factor (VEGF) to repair a defect in the femoral diaphysis of mice. MSC isolated from bone marrow of 4-month-old donor mice were seeded in type I collagen gels that were then compressed to form scaffolds with a fibrillar density similar to osteoid. The cells remained metabolically active in scaffolds incubated in vitro for up to 15 days and differentiated into osteoblasts that deposited calcium-phosphate mineral into the scaffold, which was quantified using micro-computed tomographic (micro-CT) imaging. When implanted in a 1 mm x 3 mm unicortical defect the MSC-loaded scaffolds were rapidly mineralised and integrated into host bone with administration of 10 ng of recombinant VEGF injected into the femoral canal at 4 days postoperative. Empty scaffolds and MSC-seeded scaffolds implanted in defects that did not receive a bolus dose of VEGF did not mineralise or integrate with native bone. The approach with MSC, hydrogels and a biologic factor already approved for human use warrants further pre-clinical investigation with a large animal model.

Volaemic assessment of the elderly hyponatraemic patient: reliability of clinical assessment and validation of bioelectrical impedance analysis

BACKGROUND

Hyponatraemia is the commonest electrolyte disturbance of hospital inpatients. Assessment of volaemic status is an important part of diagnosis and management.

AIM

To determine reliability of clinical assessment of volaemic state by assessing inter-observer variability of clinical measures of volaemic state. To assess validity of bioelectrical impedance analysis as a tool to measure total body water in elderly hyponatraemic patients.

DESIGN

Observational study conducted in a Department of Medicine for the Elderly.

METHODS

Hospital inpatients >65 years old (n=22) with serum sodium concentration <130 mmol/l were included. Two assessors determined volaemic state on two occasions 72 h apart. Level of agreement between observers was determined on each occasion. Total body water estimation was undertaken with bioelectrical impedance analysis and measurement of dilution of deuterium oxide. Correlation between these two measures was then analysed.

RESULTS

Cohen's κ for agreement between two observers for overall assessment of volaemic state was 0.59 (P<0.01). Values for agreement between individual clinical markers of volaemic state ranged between 0.16 and 0.45. Pearson correlation coefficient (r) for correlation between estimation of total body water undertaken by bioelectrical impedance analysis and by measurement of dilution of deuterium oxide was 0.69 (P<0.001).

CONCLUSION

There was moderate inter-observer agreement of overall clinical volaemic assessment of elderly hyponatraemic patients. Total body water estimation by bioelectrical impedance analysis correlates well with estimation by measurement of dilution of deuterium oxide, providing a potentially useful tool to improve the management of the elderly hyponatraemic patient.

Identification of prognostically-relevant signature genes differentially expressed between primary colorectal carcinoma and hepatic metastasis

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Background: Colorectal cancer (CRC) is the third most common cancer in the US. Hepatic metastasis (HM), the most common distant metastasis from CRC and occurring in about 60% of CRC patients during the course of their treatment, is a significant clinical problem. Although several clinical prognostic factors for HM from CRC have been identified, little is known about its molecular aspect. Methods: Under IRB approved protocols, we profiled gene expression in a set of 30 specimens from primary CRC and 31 unmatched specimens of HM from CRC. To survey the molecular variations between the two groups, we used cDNA microarrays containing ∼22,000 human genes, and identified differentially expressed genes using the Significance Analysis of Microarrays (SAM) method. To further characterize the clinical relevance of differentially expressed genes, we used immunohistochemistry (IHC) on tissue microarrays of tumor tissues obtained from an independent dataset of 154 patients with primary CRC. Results: Supervised analysis using SAM identified >200 genes with significantly higher expression in HM from CRC compared to primary CRC (and also compared to normal liver), with a false discovery rate (FDR) of <1%. IHC staining of two highly ranked differentially expressed signature genes, SPP1 (osteopontin) and LEF1 (lymphoid enhancer factor-1; a transcriptional mediator of Wnt pathway activation), showed protein overexpression (OE) in 60% and 44% of CRC cases, respectively; with a significant correlation with liver involvement in LEF1 expression (chi-square p=0.04) vs. SPP1 OE (p=0.14). Kaplan Meier analysis revealed significantly worsening survival in patients with LEF1 OE (p<0.01), but not SPP1 (p=0.14). Multivariate analysis identified several relevant prognostic markers: stage (p<0.001), nodal status (p <0.01) and LEF1 OE (p=0.02). Conclusions: Among signature genes differentially expressed between CRC and HM, we demonstrate LEF1, not SPP1, OE to be a poor prognostic factor for survival. Further studies are needed to characterize other signature genes, and to refine our understanding of the role of altered LEF1 expression in CRC tumorigenesis.

No significant financial relationships to disclose.

Endosome fusion in living cells overexpressing GFP-rab5

CHO and BHK cells which overexpress either wild-type rab5 or rab5:Q79L, a constitutively active rab5 mutant, develop enlarged cytoplasmic vesicles that exhibit many characteristics of early endosomes including immunoreactivity for rab5 and transferrin receptor. Time-lapse video microscopy shows the enlarged endosomes arise primarily by fusion of smaller vesicles. These fusion events occur mostly by a ‘bridge’ fusion mechanism in which the initial opening between vesicles does not expand; instead, membrane flows slowly and continuously from the smaller to the larger endosome in the fusing pair, through a narrow, barely perceptible membranous ‘bridge’ between them. The unique aspect of rab5 mediated ‘bridge’ fusion is the persistence of a tight constriction at the site where vesicles merge and we hypothesize that this constriction results from the relatively slow disassembly of a putative docking/fusion complex. To determine the relation of rab5 to the fusion ‘bridge’, we used confocal fluorescence microscopy to monitor endosome fusion in cells overexpressing GFP-rab5 fusion proteins. Vesicle docking in these cells is accompanied by recruitment of the GFP-rab5 into a brightly fluorescent spot in the ‘bridge’ region between fusing vesicles that persists throughout the entire length of the fusion event and which often persist for minutes following endosome fusion. Other endosomal membrane markers, including FM4-64, are not concentrated in fusion ‘bridges’. These results support the idea that the GFP-rab5 spots represent the localized accumulation of GFP-rab5 between fusing endosomes and not simply overlap of adjacent membranes. The idea that the GFP-rab5 spots do not represent membrane overlap is further supported by experiments using photobleaching techniques and confocal imaging which show that GFP-rab5 localized in spots between fusion couplets is resistant to diffusion while GFP-rab5 on endosomal membranes away from these spots rapidly diffuses with a rate constant of about 1.0 (+/-0.3) x10(-)(9)cm(2)/second.

Genetic and physiologic analysis of the role of uncoupling protein 3 in human energy homeostasis

By virtue of its potential effects on rates of energy expenditure, uncoupling protein 3 (UCP3) is an obesity candidate gene. We identified nine sequence variants in UCP3, including Val9Met, Val102Ile, Arg282Cys, and a splice site mutation in the intron between exons 6 and 7. The splice mutation results in an inability to synthesize mRNA for the long isoform (UCP3L) of UCP3. Linkage (sib pair), association, and transmission disequilibrium testing studies on 942 African-Americans did not suggest a significant effect of UCP3 on body composition in this group. In vastus lateralis skeletal muscle of individuals homozygous for the splice mutation, no UCP3L mRNA was detectable; the short isoform (UCP3S) was present in an increased amount. In this muscle, we detected no alterations of in vitro mitochondrial coupling activity, mitochondrial respiratory enzyme activity, or systemic oxygen consumption or respiratory quotient at rest or during exercise. These genetic and physiologic data suggest the following possibilities: UCP3S has uncoupling capabilities equivalent to UCP3L; other UCPs may compensate for a deficiency of bioactive UCP3L; UCP3L does not function primarily as a mitochondrial uncoupling protein.

Heterozygosity for Lep(ob) or Lep(rdb) affects body composition and leptin homeostasis in adult mice

In an effort to understand the genetics of human obesity, we have studied the physiology and molecular genetics of rodent models with monogenetic forms of obesity including the leptin gene-defective (Lep(ob)/Lep(ob)) and leptin receptor gene-defective (Lep(rdb)/Lep(rdb)) mouse. In the experiments reported here, we investigated the effects of heterozygosity at Lep(ob) and Lep(rdb) on body composition and circulating leptin concentration in +/+, Lep(rdb)/+, and Lep(ob)/+ adult mice to identify possible gene dosage effects of these mutations that might elucidate their physiology. Adult mice heterozygous for the Lep(ob) or Lep(rdb) allele had equivalent fat mass and percentage body fat, which was increased 27-47% and 23-35%, respectively, relative to +/+ littermates. Plasma leptin concentrations adjusted for fat mass were 6.5 ng/ml in the Lep(ob)/+, 9.6 ng/ml in the +/+, and 11.5 ng/ml in the Lep(rdb)/+ mice. Sex had no effect on plasma leptin after controlling for fat mass. These data, and data from a small number of mice heterozygous at both Lep(ob) and Lep(rdb) (compound heterozygotes), suggest that leptin protein produced per mass of body fat is reduced in Lep(ob)/+ mice and that body fat is increased in Lep(ob)/+ mice until plasma leptin concentrations reach that of a normal +/+ mouse. The elevated plasma leptin concentration in the Lep(rdb)/+ mice suggests that LEPR may mediate autocrine suppression of Lep expression. These results raise the possibility that human mutations that have even subtle effects on the leptin/leptin receptor system in either the homozygous or heterozygous state may have significant effects on adiposity.

Genetic modifiers of Leprfa associated with variability in insulin production and susceptibility to NIDDM

In an attempt to identify the genetic basis for susceptibility to non-insulin-dependent diabetes mellitus within the context of obesity, we generated 401 genetically obese Leprfa/Leprfa F2 WKY13M intercross rats that demonstrated wide variation in multiple phenotypic measures related to diabetes, including plasma glucose concentration, percentage of glycosylated hemoglobin, plasma insulin concentration, and pancreatic islet morphology. Using selective genotyping genome scanning approaches, we have identified three quantitative trait loci (QTLs) on Chr. 1 (LOD 7.1 for pancreatic morpholology), Chr. 12 (LOD 5.1 for body mass index and LOD 3.4 for plasma glucose concentration), and Chr. 16 (P < 0.001 for genotype effect on plasma glucose concentration). The obese F2 progeny demonstrated sexual dimorphism for these traits, with increased diabetes susceptibility in the males appearing at approximately 6 weeks of age, as sexual maturation occurred. For each of the QTLs, the linked phenotypes demonstrated sexual dimorphism (more severe affection in males). The QTL on Chr. 1 maps to a region vicinal to that previously linked to adiposity in studies of diabetes susceptibility in the nonobese Goto-Kakizaki rat, which is genetically closely related to the Wistar counterstrain we employed. Several candidate genes, including tubby (tub), multigenic obesity 1 (Mob1), adult obesity and diabetes (Ad), and insulin-like growth factor-2 (Igf2), map to murine regions homologous to the QTL region identified on rat Chr. 1.

Tension distribution of single motor units in multitendoned muscles: comparison of a homologous digit muscle in cats and monkeys

To determine whether single motor units (MUs) in multitendoned muscles distribute tension to multiple tendons or instead focus tension selectively on a single tendon, we examined the distribution of tension generated by single MUs in the cat extensor digitorum lateralis (EDLat), and in its macaque homolog, the extensor digiti quarti et quinti (ED45). General properties of MUs (maximal tetanic tension, axonal conduction velocity, and twitch rise time) were similar in these muscles to those reported for other limb muscles in cats and monkeys. Most cat EDLat MUs were found to exert tension rather selectively on one of the three tendons of the muscle. Fast fatigable MUs were slightly but significantly more selective than fast fatigue-resistant and slow MUs. In contrast, and contrary to expectation, the macaque ED45 contained a lower proportion of MUs that exerted tension selectively on one of the two tendons of the muscle, and a higher proportion of relatively nonselective MUs. These findings suggest that the cat EDLat may consist of three functional subdivisions, each acting preferentially on a different tendon, whereas the macaque ED45 is more likely to function as a single multitendoned muscle.

Genomic structure of the human OB receptor and identification of two novel intronic microsatellites

Identification of the OB (leptin) receptor (OBR) as the gene that is defective in diabetes (Leprdb) mice and fatty (Leprfa) rats provides an important candidate gene for the study of the genetics of human obesity. We defined the boundaries of the 18 coding exons for the long form of OBR, and sequenced the immediately adjacent intronic regions. These sequences can be used to generate reagents for genetic analysis (e.g., direct sequencing, single-stranded conformational polymorphism analysis, etc.) of the possible role of OBR in the regulation of adiposity in humans. In addition, we have identified two highly polymorphic intronic microsatellites that can be scored with the polymerase chain reaction.