Evaluation of Thalassaemia Screening Tests in the Antenatal and Non-Antenatal Populations in Singapore.

INTRODUCTION: Haemoglobinopathy testing is performed for carrier screening and evaluation of microcytic anaemia. We evaluated the effectiveness of thalassaemia screening tests at our institution and suggest ways of improving the testing algorithm. MATERIALS AND METHODS: A total of 10,084 non-antenatal and 11,364 antenatal samples with alkaline gel electrophoresis (AGE), capillary electrophoresis (CE), haemoglobin H (HbH) inclusion test, mean corpuscular haemoglobin (MCH) and mean corpuscular volume (MCV) were retrospectively reviewed. A subgroup of 187 samples with genetic testing was correlated with HbH inclusions and MCH/ MCV. The effect of iron deficiency on percentage hemoglobin A2 (HbA2) was studied. RESULTS: HbH inclusion test showed low sensitivity of 21.43% for α-thalassaemia mutations but higher sensitivity of 78.95% for --SEA deletion. By receiver operating characteristic (ROC) analysis, MCH ≤28 pg or MCV ≤80 fl for non-antenatal samples and MCH ≤27 pg or MCV ≤81 fl for antenatal samples had >98% sensitivity for HbH inclusions. Above these thresholds, the probability that HbH inclusions would be absent was <99% (negative predictive value [NPV] >99%). MCH ≥28 pg had 100% sensitivity (95% CI 95.63%-100%) for α-thalassaemia mutations and 97.68% calculated NPV in the antenatal population. Detection of haemoglobin variants by CE correlated highly with AGE (99.89% sensitivity, 100% specificity). Severe iron deficiency reduced HbA2 in hemoglobin (P <0.001) and α-thalassaemia (P = 0.0035), but not in ß-thalassaemia. CONCLUSION: MCH/MCV thresholds have adequate sensitivity for α-thalassaemia in the antenatal population, and genotyping plays an important role as HbH inclusion test shows low sensitivity. CE without AGE, may be used as initial screening for haemoglobin variants. Our study provides contemporary data to guide thalassaemia screening algorithms in Singapore.

Evaluation of sorafenib in Chinese unresectable hepatocellular carcinoma patients with prior surgery and portal vein tumor thrombosis: A subset analysis of GIDEON study data.

The purpose of this study was to examine the safety and efficacy of sorafenib in Chinese patients with unresectable hepatocellular carcinoma. Data of 338 Chinese patients from the Global Investigation of therapeutic DEcisions in hepatocellular carcinoma and Of its treatment with sorafeNib study database were included. Patients were divided into those who received and did not receive sorafenib prior to surgical resection and those with and without portal vein tumor thrombosis. In the non-surgery group, the median survival was 302 days (95% confidence interval: 244-371), and the median time from diagnosis to death was 428 days (95% confidence interval: 352-556); in the surgery group, half of the patients survived for 345 days and the median time from diagnosis to death was 1000 days (95% confidence interval: 750-2816). Median progression-free survival and median time to progression were not different between the two groups. Median overall survival was 360 days (95% confidence interval: 309-435) in the non-portal vein tumor thrombosis group and 240 days (95% confidence interval: 181-296) in the portal vein tumor thrombosis group; median time between hepatocellular carcinoma diagnosis and death was 750 days (95% confidence interval: 472-1000) and 420 days (95% confidence interval: 252-567), respectively, in the two groups. Median progression-free survival was 209 days (95% confidence interval: 166-264) for patients without portal vein tumor thrombosis and 154 days (95% confidence interval: 112-202) for patients with portal vein tumor thrombosis; median time to progression was 295 days (95% confidence interval: 209-463) and 221 days, respectively. Adverse events were generally comparable regardless of prior surgery and portal vein tumor thrombosis status. We thus conclude that earlier administration of sorafenib may result in improved outcomes in patients with unresectable hepatocellular carcinoma and portal vein tumor thrombosis.

Patterns of sorafenib and TACE treatment of unresectable hepatocellular carcinoma in a Chinese population: subgroup analysis of the GIDEON study.

To analyze safety and efficacy of patterns of sorafenib and TACE therapy under real-life clinical practice conditions. A total of 338 Chinese patients with unresectable hepatocellular carcinoma (HCC) from the international database of the GIDEON non-interventional trial were included in this analysis. Endpoints were overall survival (OS), progression-free survival (PFS), time to progression (TTP) and safety. Two major patterns in the use of sorafenib observed in current Chinese clinical practice were: sorafenib administration subsequent to transarterial chemoembolization (TACE) treatment (n = 226, 66.9%) and sorafenib administration concomitant to TACE (n = 80, 35.4%). Patients receiving TACE prior to sorafenib had worse liver function (43.8% BCLC stage Cat diagnosis and 62.1% BCLC stage C at study entry) than those receiving TACE concomitant to sorefenib (35.0% BCLC stage C at diagnosis and 51.3% BCLC stage three at study entry). For patients undergoing prior TACE and concomitant TACE treatment, median OS time was 354 days vs. 608 days, PFS time was 168 days vs. 201 days, and TTP was 214 days vs. 205 days; and the percentage of patients who experienced drug-related adverse effects after sorafenib therapy in these two groups were 33.3 and 50.0%, respectively. Sorafenib treatment is usually administered in cases of tumor progression or poor liver function status after TACE treatment in China. Under such conditions, patients still gained a relatively satisfactory survival outcome. In addition, the present study suggests that concomitant sorafenib and TACE treatments may lead to a better prognosis, although differences in baseline characteristics may have contributed in part to the better outcomes.

Safety and efficacy of sorafenib therapy in patients with hepatocellular carcinoma: final outcome from the Chinese patient subset of the GIDEON study.

We report data from the final analysis of the Chinese subset of the GIDEON (the Global Investigation of therapeutic DEcisions in hepatocellular carcinoma and Of its treatment with sorafeNib) study, which evaluated the safety and efficacy of sorafenib in Child-Pugh A, B and C patients with unresectable hepatocellular carcinoma (uHCC) in real-life clinical practice. Patient demographics, disease characteristics and treatment history were recorded at enrollment; dose, adverse events (AEs) and efficacy were recorded at follow-up. Of the 338 evaluable patients, 98.5% started on 800 mg/day sorafenib, regardless of their Child-Pugh status. The median treatment duration (21.1 vs. 18.8 weeks) and median overall survival (322 vs 240 days) were longer in patients with Child-Pugh A compared with the Child-Pugh B, progression-free survival were 183 vs. 208 days, respectively). AEs (all grades) were comparable in the Child-Pugh B vs A group (56.3% vs. 50.4%, respectively), moreover, the Child-Pugh B group also had comparable rates of drug-related AEs (35.4% vs. 27.2%, respectively) and serious AEs (25.0% vs. 23.0%, respectively) compared with the Child-Pugh A group. The overall dosing strategy was consistent in Chinese patients across Child-Pugh subgroups. Tolerability and safety data suggest that Child-Pugh B patients might be safely treated with sorafenib. The findings from our study showed that safety profile of sorafenib in terms of rate and type of AEs is similar to the global international GIDEON study as well as other pivotal studies.

Differences in the resting platelet proteome and platelet releasate between healthy children and adults.

Major age-related diseases such as cardiovascular disease and cancer are the primary causes of morbidity and mortality in Australia and worldwide. In our recent study characterising differences in the plasma proteome between healthy children and adults, a large number of proteins differentially expressed with age were found to be of platelet origin. This study aimed to characterise differences in the resting platelet proteome and the platelet releasate of healthy children compared to healthy adults. This study represents the setup of a procedure for the proteomic analysis of platelets from children. Differentially expressed platelet proteins were identified using Two-dimensional Differential In-Gel Electrophoresis and mass spectrometry. Significant differences in the expression of nine proteins (1.1%) in the resting platelet proteome were observed in children compared to adults. Serotransferrin, fibrinogen alpha chain, glyceraldehyde-3 phosphate dehydrogenase, serum albumin, transgelin-2, calponin-2/LIM and SH3 domain protein 1 and human chorionic gonadotropin 2039797 were up-regulated, whereas thrombospondin-1 was down-regulated in children. Eleven proteins (1.5%) were differentially expressed in the platelet releasate of children compared to adults, where transferrin was also upregulated and TSP-1 was down regulated. Identified proteins are involved in processes including tissue and organ development, cell proliferation regulation and angiogenesis. Our results provide novel insights into platelet physiology as well as growth, development and ageing in healthy individuals. BIOLOGICAL SIGNIFICANCE: The incidence of major diseases such as cardiovascular disease (CVD) and cancer increase with increasing age and are the major causes of morbidity and mortality both in Australia and worldwide. As the aged population continues to increase dramatically, so too will the financial strains associated with the long term care of the elderly population. Compared to adults, children have a significantly lower incidence of major diseases such as thromboembolic disease. This suggests that children have a protective mechanism against the development of disease. Therefore, studies focussing on the molecular changes of proteins, the machinery of the cell, between children and adults are the key to determining the underlying mechanisms responsible for the onset of major diseases. A well-defined example of how protein expression can change with age is that of the plasma proteome. Significant differences in the expression of numerous plasma proteins between healthy children and adults have been recently demonstrated. Interestingly, a large number of differentially expressed proteins were found to be of platelet origin. This finding forms the basis for the current study, presenting as strong evidence for the age-specific differences of the platelet proteome.

Platelets from children are hyper-responsive to activation by thrombin receptor activator peptide and adenosine diphosphate compared to platelets from adults.

Platelets are crucial subcellular elements of haemostasis at sites of vascular injury and are also known to be immune mediators in pathological thrombosis. Despite the integral role of platelets in many disease processes, there is very little information available on platelet function and response to agonists in healthy children. We recently reported important differences in the interaction of platelets with monocytes in the circulation, including increased formation of monocyte-platelet aggregates (MPAs) without concomitant increase in P-selectin expression. Our current study investigates parameters of platelet activation (PAC-1 binding and P-selectin expression) and MPA formation in response to a range of physiologically relevant platelet agonists in healthy children compared to healthy adults. All parameters were significantly higher in children in response to sub-maximal concentrations of thrombin receptor activator peptide and adenosine diphosphate, reflecting an age-specific difference in agonist-stimulated platelet reactivity in children. The results of our study challenge the general assumption that platelet reactivity in children is similar to adults. This finding is fundamental to investigating the role of platelets in diseases of childhood and pathogenesis of adult-based diseases that have their origins in childhood. Our findings underscore the need for age-specific reference ranges for platelet function in children rather than extrapolation from adult data.

Exploring the potential of platelet proteomics in children.

Proteomics is a rapidly evolving ''post-genomic'' science utilizing advanced technologies in protein separation, identification, quantitation and heavily relying on bioinformatics. Proteomic research in pediatrics is important and most of the successes thus far are seen in research that utilize samples that require less invasive procedures and focus on prevailing childhood diseases such as acute lymphoblastic leukaemia and neuroblastoma. Recent advances in proteomics are helping to elucidate platelet processes that are relevant to bleeding and clotting disorders, as well as other important roles of platelets such as in angiogenesis and inflammation. Nevertheless, most of platelet proteome data obtained to date are derived from the adult population and the potential of platelet proteomic application in children has not yet been explored. As it happens in all research fields, there are additional challenges in studying children such as procuring sufficient biological samples and access to less common disease cohorts as compared to in adults. Furthermore, many of the prevalent platelet-mediated diseases in adults, such as coronary heart disease and atherosclerotic lesions, are believed to have origins during childhood. Hence, platelet proteomic research in children may reveal some important information on how platelet plays a role in the pathogenesis of disease. In this article, we refer to the current knowledge from platelet proteomic research strategies in adults and address the specific concerns in the study of pediatric samples.

Day-case Karydakis flap for pilonidal sinus.

PURPOSE: The Karydakis flap for pilonidal sinus is associated with primary wound healing and infrequent recurrence. Previous studies had reported in-patient protocols. This cohort study was designed to assess the feasibility, safety, and practicalities of day-case Karydakis flap surgery. Factors relating to wound healing also were explored. METHODS: Consecutive patients undergoing day-case Karydakis flap surgery, by one consultant surgeon, for pilonidal sinus were studied prospectively. Patients were assessed at weekly intervals after surgery until healing was complete. Wound healing time was compared with 1) patients' gender, age, body mass index, deprivation index, occupation and smoking status, 2) pilonidal diseases' dimensions and proximity to anus, 3) wounds' dimensions and proximity to anus, and 4) drain volume. RESULTS: Day-case Karydakis flap surgery was feasible, safe, and effective. None of the 51 patients in the study required readmission to hospital, sepsis drainage, or surgery for recurrent sinus. Median wound healing time was three weeks. Smokers healed quicker than nonsmokers. No other factors were identified that were associated with delayed healing. Normal activity was resumed within one month of surgery in 95 percent of patients. CONCLUSIONS: The Karydakis flap can offer the advantage of day-case surgery for pilonidal sinus patients in addition to primary wound healing and low sinus recurrence rates.

An investigation of the effects of the MEK inhibitor U0126 on apoptosis in acute leukemia.

Blockade of mitogen-activated protein kinase kinase (MEK1/2), part of the extracellular signal-regulated kinase (ERK) or p44/42 mitogen-activated protein kinase (MAPK) pathway has been shown, in some instances, to cause apoptosis in leukemic blast cells. However, studies are contradictory and have often been based mainly on inhibition of cell growth in a limited number of cell lines. This investigation examined the effect of the potent MEK inhibitor U0126 alone and in combination with Ara-C on apoptosis in acute myeloblastic leukemia (AML) cell lines, patient acute leukemic and nonleukemic samples. Apoptosis was assessed flow cytometrically using Apo2.7 and AnnexinV antibodies which detect apoptosis at the mitochondrial and cell membrane levels, respectively. The proapoptotic effect of the inhibitor varied across the five cell lines tested, from highly significant induction of apoptosis to no apparent response. A possible synergistic effect with the combined use of U0126 and Ara-C was observed in one cell line only. The proapoptotic effect of U0126 in the most sensitive cell line appeared to be related to CD34 positivity. Cells from leukemic patients showed considerable sensitivity in two of four cases with a similar association with CD34 expression being evident. Interestingly, control cells did not show a significant effect when exposed to the inhibitor. These results suggest that U0126 may offer a potential alternative to standard chemotherapy with a particular role in the most primitive types of leukemia, these being often the most resistant to standard chemotherapy.