Clinical outcome of neoadjuvant chemoradiation in locally advanced rectal cancer at a tertiary hospital

OBJECTIVES

To review the clinical outcome of locally advanced rectal cancer treated with neoadjuvant chemoradiation followed by definitive surgery with or without adjuvant chemotherapy and to elucidate the prognostic factors for treatment outcome.

METHODS

This historical cohort study was conducted at a tertiary public hospital in Hong Kong. All patients who had undergone neoadjuvant chemoradiation for locally advanced rectal cancer in our department from November 2005 to October 2014 were recruited. Local recurrence-free survival, distant metastasis-free survival, disease-free survival, and overall survival of patients were documented.

RESULTS

A total of 135 patients who had received neoadjuvant chemoradiation during the study period were reviewed. There were 130 patients who had completed neoadjuvant chemoradiation and surgery. The median follow-up time was 35.1 months. The 3- and 5-year local recurrence-free survival, distant metastasis-free survival, disease-free survival, as well as overall survival rates were 91.8% and 86.7%, 73.9% and 72.1%, 70.1% and 64.6%, as well as 86.5% and 68.4%, respectively. The rate of pathological complete response was 13.8%. The T and N downstaging rate was 49.2% and 63.1%, respectively. The rate of conversion from threatened circumferential resection margin to clearance of margin was 90.6%. Of the 42 cases that were initially deemed to require abdominal perineal resection, 15 (35.7%) were converted to sphincter-sparing surgery.

CONCLUSIONS

The treatment outcome of neoadjuvant chemoradiation for locally advanced rectal cancer was comparable with overseas data in terms of local control rate and overall survival. This strategy may increase the chance of achieving a clear surgical margin by downstaging the tumour, especially in patients who presented with threatened circumferential margin.

Registered Replication Report: Schooler and Engstler-Schooler (1990)

Trying to remember something now typically improves your ability to remember it later. However, after watching a video of a simulated bank robbery, participants who verbally described the robber were 25% worse at identifying the robber in a lineup than were participants who instead listed U.S. states and capitals-this has been termed the "verbal overshadowing" effect (Schooler & Engstler-Schooler, 1990). More recent studies suggested that this effect might be substantially smaller than first reported. Given uncertainty about the effect size, the influence of this finding in the memory literature, and its practical importance for police procedures, we conducted two collections of preregistered direct replications (RRR1 and RRR2) that differed only in the order of the description task and a filler task. In RRR1, when the description task immediately followed the robbery, participants who provided a description were 4% less likely to select the robber than were those in the control condition. In RRR2, when the description was delayed by 20 min, they were 16% less likely to select the robber. These findings reveal a robust verbal overshadowing effect that is strongly influenced by the relative timing of the tasks. The discussion considers further implications of these replications for our understanding of verbal overshadowing.

A randomized controlled trial comparing polyethylene glycol + ascorbic acid with sodium picosulphate + magnesium citrate solution for bowel cleansing prior to colonoscopy

INTRODUCTION

Adequate bowel cleansing which is acceptable to the patient is a prerequisite for safe and effective colonoscopy. A 2-L polyethylene glycol solution containing ascorbic acid and electrolytes (PEG-Asc) is an alternative to sodium picosulphate + magnesium citrate (SPS-Mg) for bowel preparation. The aim of the current study is to compare PEG-Asc to SPS-Mg in terms of tolerability and efficacy.

METHODS

This was a single blind, randomized controlled trial. A blinded assessment of bowel cleansing was made by the attending endoscopist. Patients completed a questionnaire on the acceptability of the preparation.

RESULTS

One hundred and thirty (130) consecutive patients attending for day case colonoscopy were randomly allocated to bowel preparation with PEG-Asc (n = 66) or SPS-Mg (n = 64). More patients found PEG-Asc to taste unpleasant (37.9 vs. 10.9%, P < 0.001) and more patients found PEG-Asc to be a more distressing preparation than SPS-Mg (15.1 vs. 4.7%, P = 0.043). However, there was no difference in the proportion of patients being able to complete bowel preparation (PEG-Asc vs. SPS-Mg, 92.4 vs. 93.8%, P = 0.520). There was no detectable difference between PEG-Asc and SPS-Mg in the quality of cleansing with a good or very good preparation being reported by the endoscopist in 46.9 and 54.5% of cases, respectively (P = 0.242).

CONCLUSIONS

More patients find PEG-Asc to taste unpleasant and to be a more distressing preparation than SPS-Mg. However, there was no detectable difference between PEG-Asc and SPS-Mg in bowel cleansing prior to colonoscopy.

Increased IL-17 and IL-21 producing TCRαβ+CD4−CD8− T cells in Chinese systemic lupus erythematosus patients

Background: Increased numbers of TCRαβ+CD4−CD8− T cells in the peripheral blood of systemic lupus erythematosus (SLE) patients in the United States and United Kingdom have been reported. However, the proportions of TCRαβ+CD4−CD8− T cells and their involvement in the pathogenesis of SLE in Chinese populations are yet to be determined. Methods: A total of 120 SLE patients, 38 rheumatoid arthritis (RA) patients and 43 normal control subjects were examined. The proportion of TCRαβ+CD4−CD8− T cells in the peripheral blood, Fas expression on these cells, and intracellular cytokine levels in these cells were assessed using flow cytometry. Plasma cytokine concentrations were measured using enzyme-linked immunosorbent assay. Results: The percentages of TCRαβ+CD4−CD8− T cells were increased in Chinese SLE patients, particularly in active SLE patients, correlated with decreased Fas expression on these cells. IL-17 and IL-21 levels in the blood and in TCRαβ+CD4−CD8− T cells from SLE patients were increased. Moreover, a positive correlation was evident between IL-17- and IL-21-producing TCRαβ+CD4−CD8− T cells. Conclusions: Increased TCRαβ+CD4−CD8− T cells expressing inflammatory cytokines, such as IL-17 and IL-21, may be implicated in the pathogenesis of SLE in patients. Appropriate IL-17- and/or IL-21 blockage may be utilized as a novel immunotherapeutic strategy for SLE patients.

Prenatal exposure to allergen, DNA methylation, and allergy in grandoffspring mice

BACKGROUND

Prenatal allergen exposure has been linked to both induction and protection of allergic sensitization in offspring. We hypothesized that prenatal exposure of mice (F0) to Aspergillus fumigatus (A. fumigatus) would be associated with decreased immunoglobulin (Ig) E and airway eosinophilia and alterations in CpG methylation of T-helper genes in third-generation mice (F2).

METHODS

Female BALB/c mice were sensitized to A. fumigatus (62.5, 125, 1250 μg, or saline) and re-exposed to the same dose on days 7 and 14 (early) or days 12 and 17 (late) gestation. Grandoffspring were treated with A. fumigatus (62.5 μg) at 9 weeks. IgE, IgG(1) , and IgG(2a) levels and cell counts from bronchoalveolar lavage fluid were determined. Lung DNA was pyrosequenced at multiple sites in the interferon (IFN)-γ and interleukin (IL)-4 promoters.

RESULTS

Grandoffspring of mothers dosed with 1250 μg early during pregnancy developed increased airway eosinophilia (P < 0.05). Grandoffspring of mothers dosed late in pregnancy developed lower IgE (P < 0.05) and airway eosinophilia (P < 0.05). Grandoffspring of mothers dosed early had lower methylation at IL-4 CpG(-408) and CpG(-393) compared to late dosed mice (P < 0.005 across all doses). Few correlations were found between methylation levels and airway eosinophilia and IgE.

CONCLUSION

Prenatal exposure to A. fumigatus late during pregnancy, but not early, was associated with lower IgE and airway eosinophilia in grandoffspring. Prenatal exposure to A. fumigatus was associated with changes in CpG methylation in the IFN-γ and IL-4 promoters that did not correlate consistently with indicators of allergic sensitization.

Measurement of an exceptionally weak electron-phonon coupling on the surface of the topological insulator Bi2Se3 using angle-resolved photoemission spectroscopy

Gapless surface states on topological insulators are protected from elastic scattering on nonmagnetic impurities which makes them promising candidates for low-power electronic applications. However, for widespread applications, these states should have to remain coherent at ambient temperatures. Here, we studied temperature dependence of the electronic structure and the scattering rates on the surface of a model topological insulator, Bi2Se3, by high-resolution angle-resolved photoemission spectroscopy. We found an extremely weak broadening of the topological surface state with temperature and no anomalies in the state's dispersion, indicating exceptionally weak electron-phonon coupling. Our results demonstrate that the topological surface state is protected not only from elastic scattering on impurities, but also from scattering on low-energy phonons, suggesting that topological insulators could serve as a basis for room-temperature electronic devices.

Photoemission spectroscopy of magnetic and nonmagnetic impurities on the surface of the Bi2Se3 topological insulator

Dirac-like surface states on surfaces of topological insulators have a chiral spin structure that suppresses backscattering and protects the coherence of these states in the presence of nonmagnetic scatterers. In contrast, magnetic scatterers should open the backscattering channel via the spin-flip processes and degrade the state's coherence. We present angle-resolved photoemission spectroscopy studies of the electronic structure and the scattering rates upon the adsorption of various magnetic and nonmagnetic impurities on the surface of Bi2Se3, a model topological insulator. We reveal a remarkable insensitivity of the topological surface state to both nonmagnetic and magnetic impurities in the low impurity concentration regime. Scattering channels open up with the emergence of hexagonal warping in the high-doping regime, irrespective of the impurity's magnetic moment.

Hereditary leukemia due to rare RUNX1c splice variant (L472X) presents with eczematous phenotype

Deleterious mutations in the RUNX1 gene cause hereditary leukemia due to a rare syndrome called Familial platelet Disorder with Associated Myeloid Malignancy (FPDMM). We describe the characteristics of a family with FPDMM due to a novel RUNX1 mutation (L472X), located in the most 3-prime end of the gene reported to date. Our 36-year old proband presented with incidentally detected thrombocytopenia and a family history suggestive of FPDMM. Contrary to previously described families, affected members of our kindred express an eczematous phenotype, reportedly most severe in members who develop leukemia. Pedigree analysis shows that the L472X mutation tracks with thrombocytopenia, acute leukemia, and eczema. The L472X mutation produces a stably expressed RUNX1 protein product with a corresponding decrease in wild type RUNX1 expression. Our data supports the inclusion of eczema in the FPDMM phenotype and suggests the possibility that the RUNX1 L472X mutant causes the type of dominant negative affect that is associated with an elevated risk of leukemia in FPDMM families.

The anti-tumour activity of allogeneic cytokine-induced killer cells in patients who relapse after allogeneic transplant for haematological malignancies

We performed a Phase I/II clinical trial to study the feasibility, toxicity and efficacy of allogeneic cytokine-induced killer (CIK) cell expansion, and treatment for patients with haematological malignancies who relapsed after allogeneic haemopoietic SCT (allo-HSCT). Allogeneic CIK cells were successfully generated for a total of 24 patients, including those from patients' own leukapheresis products in 5 patients who had no access to further donor cells. The median CD3(+) T-cell expansion was 9.33 (1.3-38.97) fold, and CD3(+)CD56(+) natural killer (NK)-like T-cell expansion was 27.77 (2.59-438.93) fold. A total of 55 infusions were done for 16 patients who had either failed or progressed after initial response to various individualized chemotherapy regimens and donor lymphocyte infusion (DLI), at doses ranging from 10 to 200 million CD3(+) cells/kg. Response attributable to CIK cell infusion was observed in five patients. These included two with ALL, two with Hodgkin's disease (HD) and one with AML, and two of whom had a response sustained for more than 2 years. Acute GVHD occurred in three and was easily treatable. This study provides some evidence suggestive of the efficacy of allogeneic CIK cells even after failure of DLI in some cases.

Correlation between cord insertion type and superficial choriovasculature in diamniotic-monochorionic twin placentas

BACKGROUND

Non-central cord insertion has been associated with diminished chorionic vascular distribution in singleton placentas. The choriovascular correlates of peripheral cord insertion in diamniotic-monochorionic twin placentas remain undetermined.

AIM

To study the association between type of cord insertion and choriovascular distribution of both twin territories in diamniotic-monochorionic twin placentas.

DESIGN

A prospective cohort of 138 monochorionic placentas was examined at Women and Infants Hospital between 2009 and early 2011. Thirty-five cases (25%), including disrupted placentas, placentas from higher order multiples and placentas from pregnancies complicated by twin-to-twin transfusion syndrome, were excluded. The correlation between cord insertion type and superficial choriovascular distribution was studied in the remaining 103 dye-injected diamniotic-monochorionic placentas. Cord insertion was categorized as paracentral, marginal or velamentous. The choriovascular distribution of each individual twin territory was assessed by analysis of number and density (number per surface area) of perforating chorionic arteries (PCA).

RESULTS

In contrast with singleton placentas, there was no correlation between cord insertion type and a twin's own choriovascular distribution in diamniotic-monochorionic placentas. However, a strong correlation was found between the choriovascular distribution of one twin and the cord insertion type of the opposite twin. For a twin with paracentral or marginal cord insertion, the PCA density was significantly higher if the co-twin had a velamentous cord insertion than if the co-twin had a paracentral cord insertion (P < 0.001 and P < 0.05, respectively). Similarly, the PCA density of a twin with velamentous cord insertion tended to be higher if the co-twin had a velamentous, rather than paracentral cord insertion (P = 0.09).

CONCLUSIONS

This is the first study to suggest that in diamniotic-monochorionic twin gestations, the choriovascular architecture correlates with the cord insertion type of the co-twin. In general, velamentous cord insertion is associated with expanded choriovascular distribution in the opposite twin territory. Our observations may reflect novel manifestations of twin interdependence in monochorionic pregnancies.

Survey on medical records and EHR in Asia-Pacific region: languages, purposes, IDs and regulations

OBJECTIVES

To clarify health record background information in the Asia-Pacific region, for planning and evaluation of medical information systems.

METHODS

The survey was carried out in the summer of 2009. Of the 14 APAMI (Asia-Pacific Association for Medical Informatics) delegates 12 responded which were Australia, China, Hong Kong, India, Indonesia, Japan, Korea, New Zealand, the Philippines, Singapore, Thailand, and Taiwan.

RESULTS

English is used for records and education in Australia, Hong Kong, India, New Zealand, the Philippines, Singapore and Taiwan. Most of the countries/regions are British Commonwealth. Nine out of 12 delegates responded that the second purpose of medical records was for the billing of medical services. Seven out of nine responders to this question answered that the second purpose of EHR (Electronic Health Records) was healthcare cost cutting. In Singapore, a versatile resident ID is used which can be applied to a variety of uses. Seven other regions have resident IDs which are used for a varying range of purposes. Regarding healthcare ID, resident ID is simply used as healthcare ID in Hong Kong, Singapore and Thailand. In most cases, disclosure of medical data with patient's name identified is allowed only for the purpose of disease control within a legal framework and for disclosure to the patient and referred doctors. Secondary use of medical information with the patient's identification anonymized is usually allowed in particular cases for specific purposes.

CONCLUSION

This survey on the health record background information has yielded the above mentioned results. This information contributes to the planning and evaluation of medical information systems in the Asia-Pacific region.

Electronic structure of the topological insulator Bi2Se3 using angle-resolved photoemission spectroscopy: evidence for a nearly full surface spin polarization

We performed high-resolution spin- and angle-resolved photoemission spectroscopy studies of the electronic structure and the spin texture on the surface of Bi2Se3, a model TI. By tuning the photon energy, we found that the topological surface state is well separated from the bulk states in the vicinity of kz = Z plane of the bulk Brillouin zone. The spin-resolved measurements in that region indicate a very high degree of spin polarization of the surface state, ~0.75, much higher than previously reported. Our results demonstrate that the topological surface state on Bi2Se3 is highly spin polarized and that the dominant factors limiting the polarization are mainly extrinsic.

Inhibition of Grb2 expression demonstrates an important role in BCR-ABL-mediated MAPK activation and transformation of primary human hematopoietic cells

Chronic myeloid leukemia (CML) results from the expression of the BCR/ABL oncogene in a primitive hematopoietic cell. However, BCR/ABL-activated signaling mechanisms are dependent on the cellular context in which it is expressed, and mechanisms underlying primitive human hematopoietic cell transformation by BCR-ABL are not well understood. Our previous studies have shown that BCR/ABL-Y177 has an essential role in Ras activation and human hematopoietic progenitor transformation in CML. The adapter protein growth factor receptor-binding protein-2 (Grb2) can bind phosphorylated BCR/ABL-Y177, induce Grb2-SoS complex formation and activate Ras signaling. We investigated the role of Grb2 in CML progenitor transformation by cotransducing human CD34+ cells with lentivirus vectors expressing short hairpin RNA to Grb2 and retrovirus vectors expressing BCR/ABL. We show that Grb2 knockdown significantly inhibits proliferation and survival of BCR-ABL-expressing CD34+ cells, but not control CD34+ cells. Grb2 knockdown reduced mitogen-activated protein kinase (MAPK) activity in BCR-ABL-expressing hematopoietic cells. We conclude that inhibition of Grb2 expression demonstrates an important role in BCR-ABL-mediated MAPK activation and transformation of primary human hematopoietic cells.These results support further investigation of downstream effectors of Grb2-mediated signals and targeting of Grb2 interactions in the treatment of CML.

Laser manipulation of atoms and particles

A variety of powerful techniques to control the position and velocity of neutral particles has been developed. As examples of this new ability, lasers have been used to construct a variety of traps, to cool atoms to temperatures below 3 x 10(-6) kelvin, and to create atomic fountains that may give us a hundredfold increase in the accuracy of atomic clocks. Bacteria can be held with laser traps while they are being viewed in an optical microscope, and organelles within a cell can be manipulated without puncturing the cell wall. Single molecules of DNA can now be stretched out and pinned down in a water solution with optical traps. These new capabilities may soon be applied to a wide variety of scientific questions as diverse as precision measurements of fundamental symmetries in physics and the study of biochemistry on a single molecule basis.