Guidelines for the treatment of myelodysplastic syndromes (MDS) in South Africa

INTRODUCTION

Myelodysplastic syndromes (MDS) encompass a heterogeneous group of clonal haematopoietic disorders characterised by chronic and progressive cytopenias resulting from ineffective haematopoiesis. Treatment is complicated by differences in disease mechanisms in different subgroups, variable clinical phenotypes and risk of progression to acute myeloid leukaemia.

RATIONALE

Changes in disease classification, prognostic scoring systems, the availability of novel treatment options and the absence of South African guidelines for the diagnosis and management of these complex disorders underpinned the need for the development of these recommendations.

METHODS

These recommendations are based on the opinion of a number of experts in the field from the laboratory as well as clinical settings and came from both the private and institutional academic environments. The most recent literature as well as available guidelines from other countries were discussed and debated at a number of different meetings held over a 2-year period.

RESULTS

A comprehensive set of recommendations was developed focusing on risk stratification, supportive management and specific treatment. Novel agents and their indications are discussed and recommendations are made based on best available evidence and taking into account the availability of treatments in South Africa.

CONCLUSION

Correct diagnosis, risk stratification and appropriate therapeutic choices are the cornerstones of success in the management of patients with myelodysplastic syndromes.

Interlayer Interactions in Self-Assembled Poly(Phenylene Vinylene) Multilayer Heterostructures, Implications for Light-Emitting and Photorectifying Diodes

Layer-by-layer molecular self-assembly has been used to fabricate multilayer heterostructures containing poly(phenylene vinylene) (PPV) and a variety of polyanions. These ultrathin films exhibit widely different photoluminescence intensities and peak positions (emission color) depending on the polyanion used. The characteristics of light-emitting devices based on such films are described. This represents the first demonstration of working organic light-emitting diodes, the active layer of which consists of ultrathin, self-assembled films of between 130 - 500 Å

Light Emitting thin Film Devices Based on Self-assembled Multilayer Heterostructures of PPV

PPV based light emitting thin film devices were fabricated using a layer-by-layer deposition technique involving the alternate spontaneous adsorption of a PPV precursor polymer and either poly(styrene-4-sulfonate) (SPS) or poly(methacrylic acid) (PMA). It was demonstrated that the polyanion used to self-assemble the PPV precursor strongly influences the characteristics and performance of the resulting LEDs. Devices fabricated with PPV created in the presence of SPS exhibited symmetric I–V curves, low luminance levels and very high current densities while PPV/PMA devices exhibited luminance levels in the range of 10–60 cd/m2 and classical rectifying behavior. These dramatic differences are primarily due to a low level of p-type doping activated during the thermal conversion of PPV and/or during device operation that confers excellent hole carrier transport capabilities to the PPV/SPS combination. Fabrication of a multi-slab type heterostructure device comprised of a PPV/SPS block (hole transporting block) and a PPV/PMA block (emitting block) resulted in improved performance with luminance levels significantly higher than previously obtained for a single slab PPV/PMA device (typically > 100 cd/m2). It was also demonstrated that the presence of very thin (about 20–30 Å thick) insulating layers at the Al/polymer interface improves device efficiency by a factor of 2–4.

Prognostic scores in a gastroenterology intensive care unit

BACKGROUND

Several prognostic systems have been developed and validated in general Intensive Care Units (ICUs). No assessment of these scores was performed in specialized Gastroenterology Intensive Care Units (GICUs).

AIM

To assess the prognostic accuracy of Acute Physiology and Chronic Health Evaluation (APACHE) II, Simplified Acute Physiology Score (SAPS) II and Sequential Organ Failure Assessment (SOFA) scores systems to predict mortality in a GICU.

METHODS

Retrospective study of 300 consecutively admissions in a GICU. Demographics, indication for admission, APACHE II, SAPS II and SOFA scores and survival at GICU discharge were recorded. Discrimination was evaluated using receiver operations characteristic (ROC) curves and area under a ROC curve (AUC). Calibration was estimated using the Hosmer-Lemeshow goodness-of-fit test.

RESULTS

Overall GICU mortality was 5.3%. APACHE II, SAPS II and SOFA mean scores of nonsurvivors (21.9, 46.2 and 9.3, respectively) were found to be significantly higher than those of survivors (11.9, 26.7 and 2.2, respectively) (p < 0.001). Discrimination was excellent for all the prognostic systems, with AUC = 0.900, 0.903 and 0.965 for APACHE II, SAPS II and SOFA, respectively. Similarly, APACHE II, SAPS II and SOFA scores achieved good calibration, with p = 0.671, 0.928 and 0.775, respectively. Among the three scores, SOFA showed the best performance, with overall correctness of prediction of 94.0%, while it was 86.2% for APACHE II and 82.7% for SAPS II.

CONCLUSIONS

in GICU, APACHE II, SAPS II and SOFA scores have excellent prognostic accuracy and, among the three scores, SOFA has the greatest overall correctness of prediction.

Thoraco-abdominal aortic aneurysm branched repair

Open thoraco-abdominal aortic aneurysm repair is a demanding procedure with high impact on the patient and the operating team. Results from expert centres show mortality rates between 3-21%, with extensive morbidity including renal failure and paraplegia. Endovascular repair of abdominal aortic aneurysms initially required an undilated portion of the aorta below the renal arteries to safely fixate the stent-graft. More complex abdominal artic aneurysms (i.e., short-necked, juxta- and suprarenal aneurysms) were later successfully treated with fenestrated grafts. The development of branched grafts opened the way to treat thoraco-abdominal aneurysms endovascularly. In this review, a comprehensive overview of technical aspects and results of the available literature is given. Mortality rates are below 10%, with spinal cord ischemia reported between 2.7% and 20%. Target vessel branch patency invariably has been reported between 95% and 100%, with first mid-term results demonstrating evidence for durability. Most series included high-risk patients, who were denied open repair. Nevertheless, risks associated with endovascular repair of thoraco-abdominal aneurysm should be acknowledged. Technique-specific complications including perforation of small vessels due to multiple catheterization resulting in retroperitoneal hematoma, and compartment syndrome of the lower limbs should be mentioned. Technical evolution of branched grafts is ongoing. Tapering down the main graft to allow for room for the branches has resulted in easier catheterization of target vessels and insertion of bridging stent-grafts. For the same reason, the branches for celiac artery and superior mesenteric artery are deliberately off-set in position. To stabilise the usually long devices, additional spiral wires have been added, to facilitate deployment in the correct orientation. Endovascular repair of thoraco-abdominal aneurysms will continue to evolve and gradually take over from open repair, in view of the much lower physical impact on the patient.

Does chair type influence outcome in the timed "Up and Go" test in older persons?

OBJECTIVE

To test the effects of the use of a collapsible, portable chair (chair B), as opposed to a 'standard' chair (chair A), on the outcome of the timed "Up and Go" (TUG) test.

DESIGN

Cross-sectional.

SETTING

Multipurpose senior centres.

PARTICIPANTS

Mobile older persons (N=118, mean age 77 years (range 62-99 years)).

OUTCOME MEASURES

Time to complete the timed "Up and Go" test using chair A and chair B, and inter-rater agreement in the time scores.

RESULTS

Time taken to complete the TUG test did not differ by chair type [median (interquartile range, IQR) = 12.3 (9.53-15.9) and 12.6 (9.7-16.6)] seconds for Chair A and B respectively, p-value=0.87. In multiple regression analyses, factors that impacted on time difference in test performance for the two chairs were use of a walking aid during the test [Odds ratio (OR) = 3.7 95%CI 1.1-11.9, p=0.031], observed difficulty with mobility (OR= 27.7 95%CI 2.6-290, p=0.006), and a history of arthritis in the knees (OR= 2.9 95%CI 1.0-8.7, P=0.05). In an inter-rater agreement analysis, no significant difference was found between time scores recorded by the two raters; median (IQR) = 12.4 (10.9-15.9) and 12.3 (7.2-59.1) seconds for the occupation therapist and for the research assistant, respectively (Wilcoxon matched pairs test, p=0.124, Spearman correlation coefficient = 0.99, p < 0.001).

CONCLUSION

The use of a portable canvas chair with standardised specifications offers an acceptable alternative to the use of a 'standard' chair in assessments of fall risk using the TUG test in field settings where field workers are reliant on public transport.

Do Mediterranean crickets Gryllus bimaculatus De Geer (Orthoptera: Gryllidae) come from the Mediterranean? Largescale phylogeography and regional gene flow

We investigate the degree of between-population genetic differentiation in the Mediterranean field cricket Gryllus bimaculatus, as well as the possible causes of such differentiation. Using cytochrome b mtDNA sequences, we estimate genetic variation in G. bimaculatus from seven South African and two Mediterranean populations. Within-population genetic variation in Europe (two haplotypes, one unique to a single individual) suggest low effective population size and strong bottlenecks with associated founder effects, probably due to cold winter environments in Europe that limit reproduction to a short part of the summer. The likely cause for this is the daily maxima in winter temperatures that fall below the critical level of 16 degrees C (enabling normal calling and courtship behaviour) in Mediterranean Europe, whereas the equivalent temperatures in southern Africa are above this limit and enable reproduction over a large part of the year. European genetic variants were either shared with Africa or closely related to African haplotypes. For survival, European populations are probably dependent on immigration from other areas, including Africa. South African populations have low but measurable gene flow with Europe and show significant between-population genetic differentiation (30 haplotypes). Isolation-by-distance is not sufficient to explain the degree of between-population genetic differences observed, and a large degree of dispersal is also required in order to account for the observed patterns. Differences in morphology and calling behaviour among these populations are underlied by these genetic differences.

Efficacy and safety of cetuximab, oxaliplatin, and capecitabine as first-line therapy for metastatic colorectal cancer (mCRC): Results of a phase II study

e15013

Background: To date, few studies have investigated the use of cetuximab in combination with oxaliplatin and capecitabine in the first-line treatment of mCRC. We therefore conducted an uncontrolled, open-label, multicenter study to evaluate the efficacy and safety of this combination in this setting. Methods: Patients (pts) received intravenous (iv) oxaliplatin 130 mg/m2 (3h day 1) plus capecitabine 1,000 mg/m2 twice daily (days 1–14) every 3 weeks (XELOX) and cetuximab 400 mg/m2 iv week 1 then 250 mg/m2 weekly over 8 cycles. Treatment was continued until disease progression (PD), unacceptable toxicity or completion of therapy. Pts were followed until death. The primary endpoint was overall response rate (ORR). A sample size of 45 pts was necessary to obtain a 95% confidence interval (CI) for ORR with a maximum width of 15% assuming an ORR of 50–80%. Results: From Sept 2005-Jan 2007, 49 pts were enrolled (ITT population): 67% male, mean age 60 (range: 44–75) years, 56.3% ECOG PS 0. Of 42 pts evaluable for ORR, 4 (9.5%) achieved a complete response, 31 (73.8%) a partial response, 6 (14.3%) had stable disease and 1 (2.4%) had PD. The ORR was 83.3% (95% CI: 72.0–94.6%). Median time to progression was 9 months (95% CI: 7.1–10.9 months). Of the 49 pts evaluable for safety, 27 (55.1%) had at least one grade 3/4 toxicity, 42 (85.7%) had acne-like rash (8 pts [16.3%] grade 3). Most common grade 3/4 toxicities included diarrhea (n=9;18.4%) and changes in potassium (n=6;12.2%). 24 (3.4%) AEs led to dose reductions (12 unrelated, 10 unlikely and 2 definitely related to cetuximab), 56 (7.8%) led to a dose delay (12 unrelated, 28 unlikely, 8 possibly, 6 probably, 2 definitely related to cetuximab) and 2 (0.3%) led to infusion rate reduction (not treatment related). 27 (55.1%) pts discontinued therapy: 10 (20.4%) due to AEs, 7 (14.3%) PD, 10 (20.4%) other reasons. 33 (67.3%) pts died: 30 (61.2%) due to PD, 2 (4.1%) intercurrent event/disease, 1 (2.0%) acute pancreatitis. The results according with the HGFR evaluation by IHC will be presented. Conclusions: In this first-line mCRC study, 83.3% of pts treated with cetuximab, oxaliplatin and capecitabine achieved an overall response. This combination appears to be a highly active and well-tolerated regimen.

No significant financial relationships to disclose.

Fatal mid-gastrointestinal bleeding by cytomegalovirus enteritis in an immunocompetent patient

Cytomegalovirus (CMV) infections are common in immunocompromised patients but rare in immunocompetent individuals. Gastrointestinal disease is frequent in systemic CMV infections but the small bowel is the least common site of involvement. We present the case of a 66 years-old man, with no evidence of immunological deficiency, hospitalized for unspecific symptoms of diarrhea, fever and abdominal pain, which developed massive mid-gastrointestinal bleeding during hospitalization. Enteroscopy revealed congestive, oedematous mucosa with multiple ulcers in the small bowel. Cytomegalic cells with intranuclear inclusions were found on histologic examination, allowing the diagnosis of CMV infection. Ganciclovir in full therapeutic dose was started and surgery was performed as a last resource treatment, but the patient died. This case highlights the rare condition of massive gastrointestinal bleeding due to CMV disease of the small bowel, the major importance of enteroscopy and pathologic evaluation for diagnosis and the poor prognosis of this situation.

Diffusion in supported lipid bilayers: influence of substrate and preparation technique on the internal dynamics

The diffusion law of DMPC and DPPC in Supported Lipid Bilayers (SLB), on different substrates, has been investigated in details by Fluorescence Recovery After Patterned Photobleaching (FRAPP). Over micrometer length scales, we demonstrate the validity of a purely Brownian diffusive law both in the gel and the fluid phases of the lipids. Measuring the diffusion coefficient as a function of temperature, we characterize the gel-to-liquid phase transition of DMPC and DPPC. It is shown that, depending on the type of substrate and the method used for bilayer preparation, completely different behaviours can be observed. On glass substrates, using the Langmuir-Blodgett deposition technique, both leaflets of the bilayer have the same dynamics. On mica, the dynamics of the proximal leaflet is slower than the dynamics of the distal leaflet, although the transition temperature is the same for both layers. Preparing bilayers from vesicle fusion in same conditions leads to more random behaviours and shifted transition temperatures.

Moderate leukocyte infiltration in the lower turbinate mucosa after a two-week intranasal administration of mometasone furoate, azelastine or salmon calcitonin

OBJECTIVE

We used light microscopy to search for local changes of the nasal mucosa associated with daily intranasal administration of mometasone furoate (MF), azelastine (AZ) or salmon calcitonin (SC).

STUDY DESIGN

Biopsies of the lower nasal turbinate were obtained from four groups of 8 individuals after 14 days of daily administration of a saline solution (control group) or of MF AZ and SC.

METHODS

Small biopsies of the anterior portion of the lower nasal turbinate were collected with the help of a Hartmann forceps under direct visual inspection. The samples were processed for light microscopy and morphometric analysis. Inflammatory infiltration (neutrophils and lymphocytes) of the nasal mucosa was evaluated by a semiquantitative method. Unpaired t test and Bernoulli distribution were applied to evaluate statistical differences between data from the different groups of samples.

RESULTS

Samples of the turbinate mucosa of all of the drug-treated groups showed a moderate enhancement in infiltrating neutrophils when compared with the samples from the control group. Infiltration of lymphocytes in the turbinate chorion was significantly different from controls only in the MF and AZ-treated groups.

CONCLUSIONS

Intranasal treatment with MF AZ or SC does not cause significant changes in the general architecture of the nasal mucosa. A moderate inflammatory response of the turbinate mucosa, that was expressed by leukocyte infiltration of epithelium and chorion, was observed in all of the 3 drug-treated groups of patients after the 2-week course of intranasal deposition of MF, AZ or SC.