Rapid detection of HLA-A*31:01 allele in DNA and blood samples using loop-mediated isothermal amplification.

BACKGROUND: The human leucocyte antigen (HLA) allele, HLA-A*31:01, is a biomarker for adverse cutaneous reactions to carbamazepine, a first-line antiepileptic drug. OBJECTIVES: To develop a platform that can rapidly detect the HLA-A*31:01 allele in blood samples to facilitate pretreatment screening. METHODS: A novel protocol based on loop-mediated isothermal amplification (LAMP) was designed and optimized. It was applied to purified genomic DNA samples derived from B-cell lines with known HLA genotypes, and to DNA and whole blood samples collected from patients with epilepsy, in whom HLA-A genotypes were determined by sequence-based typing. RESULTS: The turnaround time for the LAMP-based protocol was < 45 min. In the DNA samples derived from B-cell lines (n = 66), the sensitivity, specificity, positive predictive value and negative predictive value of the LAMP-based protocol for detecting HLA-A*31:01 were 1·00 [95% confidence interval (CI) 0·88-1·00], 0·95 (95% CI 0·82-0·99), 0·94 and 1·00, respectively. The LAMP-based protocol produced the same results in the DNA and whole blood samples collected from patients (n = 34). Its sensitivity, specificity, positive predictive value and negative predictive value in detecting HLA-A*31:01 in the patient samples were 1·00 (95% CI 0·57-1·00), 0·97 (95% CI 0·83-0·99), 0·83 and 1·00, respectively. CONCLUSIONS: The findings demonstrated the feasibility of accurately detecting HLA-A*31:01 in DNA and whole blood samples using a LAMP-based protocol. Given its rapid turnaround time, this novel platform has the potential to be adapted into a point-of-care screening test.

Toxicity burden score: a novel approach to summarize multiple toxic effects.

BACKGROUND: Toxicity data from cancer trials are summarized into a single outcome, dose-limiting toxicity (DLT), which does not account for multiple lower grade toxic effects nor differentiates between toxicity types and gradations within DLT. METHODS: Toxicity data were summarized into a toxicity burden score (TBS) using a weighted sum. The severity weights were estimated via regression using historical data. We demonstrated the method using historical data from a bortezomib trial and illustrated the advantages of defining DLT based on TBS in a simulated dose-finding trial. RESULTS: The estimated weights were 0.17, 0.40 and 0.85 for grade 1/2, grade 3 and grade 4 platelets, respectively; 0.19, 0.64, 1.03 and 2.53 for grade 1, 2, 3 and 4 neuropathy, respectively and 0.17 for each grade 3 or higher nonhematologic toxic effects unrelated to treatment. In the simulated trial, the probability of selecting doses above the maximum tolerated dose decreased when using the DLT defined based on TBS. CONCLUSIONS: TBS is a feasible approach to summarize toxicity. It includes information from the grades and types of multiple toxic effects and can be applied in all phases of drug development. Further efforts should focus on validating the method in a large prospective study before applying it in practice.

Human immunogenic T cell epitopes in nucleoprotein of human influenza A (H5N1) virus.

1. Two novel HLA-A2.1 specific H5N1 nucleoprotein epitopes(NP373-381 AMDSNTLEL and NP458-466 FQGRGVFEL) capable of activating cytotoxic T-cells in vitro were identified. 2. When the H5N1 nucleoprotein epitopes (NP373-381AMDSNTLEL and NP458-466FQGRGVFEL) were used with the single chain trimer system, they elicited effective cytotoxic T-cell responses against the corresponding nucleoprotein peptide-loaded cells in an HHD transgenic mouse model.

Sonographic study of the decidua basalis in early pregnancy loss.

OBJECTIVES: To describe the sonographic findings in the decidua basalis layer in spontaneous early pregnancy loss and to compare them with those in normal pregnancy. METHODS: We reviewed 119 scans at 4-10 weeks' gestation from 110 patients who miscarried clinically at less than 13 weeks' gestation and 132 scans also at 4-10 weeks from 98 patients who had normal uncomplicated term pregnancies. The thickness and echogenicity of the decidua basalis layer were compared between pregnancies which suffered early loss and normal controls. RESULTS: Relative thinning of the decidua basalis was observed in cases of early pregnancy loss from 5-6 weeks onwards when compared with normal pregnancies. In embryonic pregnancies that subsequently miscarried, the decidua basalis did not show the rising trend in thickness that was observed in normal pregnancies. Shortly before and after embryonic demise, the decidua appeared relatively more echogenic compared with that in normal pregnancy and the placenta showed areas of hypoechogenicity. Embryonic demise was followed by disorganization of the decidual layer, which became difficult to recognize. Pregnancy with an empty sac showed a more gradual trend in the thinning of the decidua basalis, but the uniformity and echogenicity of the layer appeared to be relatively better preserved with time. CONCLUSION: The decidua basalis layer in pregnancies that are destined to miscarry in the first trimester differs sonographically from that in normal pregnancies. The sonographic differences are suggestive of a defective decidual-placental complex resulting from deficient trophoblastic invasion.

Sonographic study of the decidua basalis in the first trimester of pregnancy.

OBJECTIVES: To describe the sonographic appearance of the decidua basalis and its changes in the first trimester of pregnancy. METHODS: We reviewed images from 159 first-trimester ultrasound examinations in 105 women with uncomplicated pregnancies who later delivered at term. The appearance of the decidua basalis layer and the sonographic changes that it underwent, including in echogenicity and thickness, were analyzed with respect to gestational age. RESULTS: A distinct decidual layer could be identified consistently at 5-6 weeks' gestation and its thickness peaked at 6-7 weeks. It was seen inconsistently at 8-9 weeks and was not identifiable by 10 weeks. Its appearance changed over time, from a uniformly echogenic layer at 5-6 weeks to a heterogeneous echogenic layer at 7 weeks, corresponding to the histological evidence of trophoblast penetration. The layer then became less echogenic with time until it became unidentifiable. CONCLUSIONS: There is a window of opportunity in the first trimester for sonographic examination of the decidua. This may allow screening, at an early stage, for conditions that affect the decidua during pregnancy.

Investigation of immunogenic T-cell epitopes in SARS virus nucleocapsid protein and their role in the prevention and treatment of SARS infection.

1. A novel HLA-A2.1-specific SARS coronavirus (SARS-CoV) nucleocapsid (N) protein epitope (N220-N228 LALLLLDRL) able to activate cytotoxic T cells in vitro has been identified. 2. When used with a single-chain-trimer system, the SARS-CoV N protein epitope (N220-N228 LALLLLDRL) can stimulate a cytotoxic T-cell response against N-protein expressing cells in the HLA-A2.1K(b) transgenic mouse model.

An interpretable health behavioral intervention policy for mobile device users.

An increasing number of people use mobile devices to monitor their behavior, such as exercise, and record their health status, such as psychological stress. However, these devices rarely provide ongoing support to help users understand how their behavior contributes to changes in their health status. To address this challenge, we aim to develop an interpretable policy for physical activity recommendations that reduce a user's perceived psychological stress, over a given time horizon. We formulate this problem as a sequential decision-making problem and solve it using a new method that we refer to as threshold Q-learning (TQL). The advantage of the TQL method over traditional Q-learning is that it is "doubly robust" and interpretable. This interpretability is achieved by making model assumptions and incorporating threshold selection into the learning process. Our simulation results indicate that the TQL method performs better than the Q-learning method given model misspecification. Our analyses are performed on data collected from 79 healthy adults over a 7 week period, where the data comprise physical activity patterns collected from mobile devices and self-assessed stress levels of the users. This work serves as a first step toward a computational health coaching solution for mobile device users.

Reduced intensity allogeneic umbilical cord blood transplantation in children and adolescent recipients with malignant and non-malignant diseases.

There is a significant amount of morbidity and mortality following myeloablative umbilical cord blood transplantation (UCBT). Reduced intensity (RI) conditioning offers an alternative to myeloablative conditioning before UCBT. We investigated RI-UCBT in 21 children and adolescents with malignant (n=14), and non-malignant diseases (n=7). RI conditioning consisted of fludarabine (150-180 mg/m2) with either busulfan (< or = 8 mg/kg)+rabbit antithymocyte globulin (R-ATG; n=16) or cyclophosphamide+R-ATG+/-etoposide (n=5). Human leukocyte antigen match: 4/6 (n=13), 5/6 (n=5) and 6/6 (n=3). The median total nucleated cell and CD34+ cell dose per kilogram were 3.58 x 10(7) and 2.54 x 10(5), respectively. The median time for neutrophil and platelet engraftment was 17.5 and 52 days, respectively. There were six primary graft failures (chronic myelogenous leukemia (CML), beta-thalassemia, hemophagocytic lymphohistiocytosis (HLH) and myelodysplastic syndrome (MDS)). The probability of developing grade II to grade IV acute graft-versus-host disease (GVHD) and chronic GVHD was 28.6 and 16.7%, respectively. Incidence of transplant-related mortality (TRM) was 14%. The 5 years overall survival (OS) in all patients was 59.8%. The 5 years OS for patients with average versus poor-risk malignancy was 77.8 versus 22.2% (P=0.03). RI-UCBT may result in graft failure in specific high-risk chemo-naïve patients (CML, beta-thalassemia, HLH and MDS), but in more heavily pretreated pediatric and adolescent recipients results in rapid engraftment and may be associated with decreased severe GVHD and TRM.

Added Value from Secondary Use of Person Generated Health Data in Consumer Health Informatics.

Introduction: Various health-related data, subsequently called Person Generated Health Data (PGHD), is being collected by patients or presumably healthy individuals as well as about them as much as they become available as measurable properties in their work, home, and other environments. Despite that such data was originally just collected and used for dedicated predefined purposes, more recently it is regarded as untapped resources that call for secondary use. Method: Since the secondary use of PGHD is still at its early evolving stage, we have chosen, in this paper, to produce an outline of best practices, as opposed to a systematic review. To this end, we identified key directions of secondary use and invited protagonists of each of these directions to present their takes on the primary and secondary use of PGHD in their sub-fields. We then put secondary use in a wider perspective of overarching themes such as privacy, interpretability, interoperability, utility, and ethics. Results: We present the primary and secondary use of PGHD in four focus areas: (1) making sense of PGHD in augmented Shared Care Plans for care coordination across multiple conditions; (2) making sense of PGHD from patient-held sensors to inform cancer care; (3) fitting situational use of PGHD to evaluate personal informatics tools in adaptive concurrent trials; (4) making sense of environment risk exposure data in an integrated context with clinical and omics-data for biomedical research. Discussion: Fast technological progress in all the four focus areas calls for a societal debate and decision-making process on a multitude of challenges: how emerging or foreseeable results transform privacy; how new data modalities can be interpreted in light of clinical data and vice versa; how the sheer mass and partially abstract mathematical properties of the achieved insights can be interpreted to a broad public and can consequently facilitate the development of patient-centered services; and how the remaining risks and uncertainties can be evaluated against new benefits. This paper is an initial summary of the status quo of the challenges and proposals that address these issues. The opportunities and barriers identified can serve as action items individuals can bring to their organizations when facing challenges to add value from the secondary use of patient-generated health data.

Sample-to-answer on molecular diagnosis of bacterial infection using integrated lab--on--a--disc.

Sepsis by bacterial infection causes high mortality in patients in intensive care unit (ICU). Rapid identification of bacterial infection is essential to ensure early appropriate administration of antibiotics to save lives of patients, yet the present benchtop molecular diagnosis is time-consuming and labor-intensive, which limits the treatment efficiency especially when the number of samples to be tested is extensive. Therefore, we hereby report a microfluidic platform lab-on-a-disc (LOAD) to provide a sample-to-answer solution. Our LOAD customized design of microfluidic channels allows automation to mimic sequential analytical steps in benchtop environment. It relies on a simple but controllable centrifugation force for the actuation of samples and reagents. Our LOAD system performs three major functions, namely DNA extraction, isothermal DNA amplification and real-time signal detection, in a predefined sequence. The disc is self-contained for conducting sample heating with chemical lysis buffer and silica microbeads are employed for DNA extraction from clinical specimens. Molecular diagnosis of specific target bacteria DNA sequences is then performed using a real-time loop-mediated isothermal amplification (RT-LAMP) with SYTO-9 as the signal reporter. Our LOAD system capable of bacterial identification of Mycobacterium tuberculosis (TB) and Acinetobacter baumanii (Ab) with the detection limits 103cfu/mL TB in sputum and 102cfu/mL Ab in blood within 2h after sample loading. The reported LOAD based on an integrated approach should address the growing needs for rapid point-of-care medical diagnosis in ICU.

Computed tomography evaluation of neck node metastases from nasopharyngeal carcinoma.

PURPOSE: To study the role of computed tomography in the pre-therapy evaluation of nasopharyngeal carcinoma. METHODS AND MATERIALS: The computed tomography of 119 new patients of nasopharyngeal carcinoma were evaluated independent of clinical findings for neck node metastases, and then compared with clinical findings. Contrast enhanced axial scans were obtained at 5 mm intervals with the infraorbitomeatal line parallel to the gantry. Scans were obtained from the supra-sellar cistern to the C5 or C6 vertebra for the evaluation of the base of skull, nasopharynx, paranasopharyngeal space and the upper and mid neck. RESULT: The present study confirmed the disparity of nodal extent documented by clinical palpation and computed tomography. Of the 37 patients who have no clinically palpable node (N0), computed tomography showed nodal involvement in 11 (29.7%) of them, and they were up-staged from N0 to N1. Computed tomography showed multiple or bilateral nodes in seven (58.3%) of the 12 patients with AJC N1 disease and they were hence up-staged to N2. All together, there were 28 (23.5%) patients who have no computed tomography evidence of nodal involvement by tumor. In agreement with clinical experience, the most commonly involved nodal groups were the upper internal jugular and upper spinoaccessary, followed by the lateral retropharyngeal. The percentage of nodes which were not clinically palpable was roughly the same for different regions (15-30%), except, as expected, that all the retropharyngeal nodes were not palpable. The risk of harboring retropharyngeal node was proportional to the size of the largest node in the ipsilateral neck. CONCLUSION: A significant proportion of patients with clinically negative neck (N0) or AJC N1 disease will be upstaged by computed tomography, thus supporting its routine use in pre-therapy evaluation of nasopharyngeal carcinoma.

Outcomes of unrelated cord blood transplantation in pediatric recipients.

We report results of unrelated cord blood transplants (UCBT) in 29 pediatric recipients in one center and the risk factors associated with survival. Median age: 9 years (0.5-20); diagnosis: ALL (9), AML (4), CML (1), HD (3), HLH (1), NHL (3), NBL (2); B-thal (1), FA (1), FEL (1), Krabbe (1), WAS (1), SAA (1); median follow-up: 11 months; conditioning: total body irradiation (TBI)-ablative (14), chemotherapy-ablative (6) and reduced intensity chemotherapy (9); GVHD prophylaxis: MMF/FK506 (18), cyclosporin A (CsA)+steroids+/-MMF (7) or CsA+methotrexate (MTX) (4); median total nucleated cells (TNC): 3.8 x 10(7)/kg (1.1-11); median CD34+: 2.3 x 10(5)/kg (0.2-9.9); and HLA match: 2 (6/6), 5 (5/6), 22 (4/6). Neutrophil engraftment by cumulative incidence curves 63% (median 28 (95% confidence interval (CI) 18-32)). Probability of >/=grade II acute graft-versus-host disease (aGVHD) by day +60 27%, >/=grade III aGVHD 20% and chronic graft-versus-host disease 3%. Estimated 1-year overall survival (OS) 46% (95% CI 30-71) and standard risk 60% (95% CI 29-100%). Variables associated with improved survival by multivariate analysis include non-TBI-ablative conditioning (P=0.024), CD34+/kg (P=0.038) and gender (P=0.048). These results suggest that CD34/kg cell dose and non-TBI-ablative conditioning may be important variables influencing OS following UCBT in pediatric recipients. Given the small number of patients, these results should be viewed cautiously.

A pilot study of reduced intensity conditioning and allogeneic stem cell transplantation from unrelated cord blood and matched family donors in children and adolescent recipients.

Reduced intensity (RI) allogeneic stem cell transplantation (AlloSCT) was initially demonstrated in adults following HLA-matched family and unrelated adult donor AlloSCT. There is little information about RI AlloSCT in children. We report results of a pilot study of RI AlloSCT in 21 recipients (< or =21 years). Age: median 13 (0.5-21) years, 8F:13M, 14 unrelated cord blood units (UCB) (10 4/6, 4 5/6), two related BM (6/6, 5/6), four related PBSC (2 6/6, 2 5/6), and one related BM+PBSC (6/6). RI: fludarabine, busulfan (n=14); fludarabine, cyclophosphamide (n=4); fludarabine, melphalan (n=1); total body irradiation, fludarabine, cyclophosphamide (n=1); or fludarabine, cyclophosphamide, and etoposide (n=1). Graft-versus-host disease prophylaxis: FK506 0.03 mg/kg/day and mycophenolate mofetil 15 mg/kg/q 12 h. UCB median nuc/kg and CD34/kg was 4.3 x 10(7)/kg (0.9-10.8) and 1.9 x 10(5)/kg (0.3-6.9), and related BM/PBSC median nuc/kg and CD34/kg was 8.3 x 10(8) (4.7-18.9) and 5.0 x 10(6)/kg (4.6-6.4). Maximal chimerism following unrelated cord blood transplantation, 100% x 7, 98% x 1, 95% x 2, 55% x 1, and 0% x 3; related PBSC/BM, 100% x 5, 65% x 1, and 55% x 1. Graft failure occurred in 5/21 (24%). In summary, RI AlloSCT in children is feasible and tolerable (< or =25% GF) and results in > or =85% of recipients initially achieving > or =50% donor chimerism.

Nasopharyngeal carcinoma: CT evaluation of patterns of tumor spread.

In a prospective study using CT as the initial means of radiologic evaluation in 262 patients with proved nasopharyngeal carcinoma, the paranasopharyngeal space was found to be the most commonly involved region (84.4%), both uni- and bilaterally. Unilateral involvement was found in 44.3% of patients (116/262) and bilateral involvement in 40.1% (105/262). The other structures or regions that were involved, in decreasing order of frequency, were the sphenoid sinus (26.7%), nasal fossa (21.8%), and ethmoid sinus (18.3%). Erosion of the base of the skull and intracranial intracranial extension into the middle cranial fossa were common (31.3% and 12.2%, respectively). The primary tumor in the nasopharynx was found to be contiguous with metastatic upper cervical nodes through paranasopharyngeal extension of tumor in 35 patients (13.4%). A qualitative method to assess the degree of paranasopharyngeal extension is proposed. The extent of paranasopharyngeal extension so evaluated was correlated with other attributes of tumor extent (p = .0001), namely, nasal or oropharyngeal extension, which constitutes a T3-level tumor, and erosion of the base of the skull or orbit, which constitutes a T4-level tumor. The extent of paranasopharyngeal extension was also correlated with local control of the tumors (p = .0001). At a median follow-up of 27 months, only three (7.9%) of the 38 patients with no paranasopharyngeal extension had nasopharyngeal relapse, while 12 (11.2%) of the 107 and 17 (34.7%) of the 49 patients with types 1 and 2 paranasopharyngeal extension, respectively, had nasopharyngeal relapse.(ABSTRACT TRUNCATED AT 250 WORDS)

Nasopharyngeal carcinoma: pattern of skeletal metastases.

The records of 153 nasopharyngeal carcinoma patients with skeletal metastases were reviewed. The skeletal system was the most common site of distant metastases. The patients who developed skeletal metastases were significantly younger than those without skeletal metastases, although there was no difference between sexes. The pattern of skeletal involvement conforms to the general pattern, the spine and pelvis being the common sites. The first region of involvement was lumbar spine (28.4%), then dorsal spine (27.7%), sacrum and pelvis (16.3%), femur (9.9%), rib and sternum (7.8%), humerus (5.0%), cervical spine (3.5%) and skull vault (1.4%). Radiologically, the lesions were lytic in 66.0%, mixed lytic and sclerotic in 12.8% and sclerotic in 21.2%. The time to development of symptomatic skeletal metastases of mixed or sclerotic nature was significantly longer than lytic lesions, and patients with mixed or sclerotic metastases also had better survival.

Reduction of radiation dose to patients undergoing barium enema by dose audit.

Nowadays, new fluoroscopic machines are usually equipped with a dose-area product (DAP) meter for dose measurement. In our hospital, DAP meters have been used in the Diagnostic Radiology Department for dose audit since June 1997. Demographic patient data, name of radiologist, fluoroscopic duration and DAP readings of every case were recorded by radiographers. In early 1999, questionnaires were distributed to radiologists who had performed fluoroscopic examinations during the auditing period. 23 radiologists with varying years of experience completed the questionnaire and their practice was analysed. Since familiarization with the examination technique would affect radiologists' practice, these radiologists were divided into two groups for analysis. Radiologists with less than 3 years of experience were grouped together as junior radiologists, whilst others were grouped as senior radiologists. Results of the questionnaire indicated that radiologists generally found DAP meters useful for dose evaluation in the process of technique refinement. Radiologists aware of being under continuous surveillance of their practice showed significant reduction of doses (junior radiologists 25%, p<0.005; senior radiologists 36%, p<0.05) and fluoroscopic times (junior radiologists 36%, p<0.001; senior radiologists 18%, p<0.05) compared with radiologists who were unaware that they were under surveillance but with similar radiological experience. This effect is believed to be because of increased awareness of radiation dose through audit. In addition, this "audit effect" may also affect junior radiologists in decision-making regarding the number of radiographs (p<0.05), but no effect was found for senior radiologists (p>0.5).

Rapid spontaneous resolution and redistribution of acute subdural hematoma in a patient with chronic alcoholism: a case report.

We report a case of a 54-year-old man who had documented traumatic acute subdural hematoma. He suffered from a transient episode of confusion and a follow-up CT scan of brain 6 h after the initial scan showed resolution and redistribution of the subdural hematoma. In this case report, we review the literature for the underlying pathophysiology of this uncommon phenomenon.

Spontaneous intracranial hypotension with diffuse dural enhancement of the spinal canal and transient enlargement of the pituitary gland.

Spontaneous intracranial hypotension is a rare phenomenon characterized by postural headache, neck rigidity, nausea and vomiting. Imaging findings on magnetic resonance imaging (MRI) is characteristic with diffuse intracranial pachymeningeal thickening and enhancement following intravenous gadolinium. We present a case of spontaneous intracranial hypotension with two unusual imaging findings; pachymeningeal enhancement of the spinal canal and enlargement of the pituitary gland in addition to the diffuse intracranial pachymeningeal enhancement. In this case report, we will discuss the clinical features, MRI findings and underlying pathophysiology of this rare condition.

Primary multifocal leptomeningeal gliomatosis.

A 23-year-old female university student was presented with recent onset of non-specific headache and dizziness. She had no neurological deficit on neurological examination and magnetic resonance imaging of the brain revealed diffuse enhancement in the basal cisterns and cerebral sulci. She was treated as tuberculous meningitis but she did not improve and developed respiratory arrest. Autopsy showed primary multifocal leptomeningeal gliomatosis.

Late temporal lobe necrosis in patients with nasopharyngeal carcinoma: evaluation with combined multi-section diffusion weighted and perfusion weighted MR imaging.

Late temporal lobe necrosis is a well-known and serious complication in patients with nasopharyngeal carcinoma (NPC) following radiotherapy. Owing to the close proximity to the skull base, the medial temporal lobes are inevitably included in the target volume of irradiation. Patients with NPC provide a unique opportunity in study of delay radiation effect in normal human brain. The objective of this study was to evaluate late temporal lobe radiation injury by combined multi-section diffusion weighted and perfusion weighted MR imaging. We prospectively studied 16 patients with typical clinical symptoms of late temporal lobe necrosis or other abnormalities in the temporal lobes incidentally detected by conventional MR imaging. All patients had a previous history of radiotherapy for histologically proven NPC. Conventional T1- and T2-weighted images, fast gradient echo with echo-planar diffusion-weighted and perfusion-weighted MR imaging were performed. Apparent diffusion coefficient (ADC) map and relative cerebral blood volume (rCBV) map were computed via commercially available software. MR diffusion and perfusion images were then analyzed and graded by two independent observers with focusing on the diffusion and perfusion mismatch. The temporal lobe lesions displayed marked high diffusion on the ADC map. The rCBV map also revealed marked hypoperfusion in these temporal lobe lesions in all patients. The areas of abnormality on the rCBV map were significantly larger than the lesions on the ADC map in 14 patients (observer 1) and 13 patients (observer 2). Since late temporal lobe necrosis is probably caused by damage of the endothelium of vessels and ischemia, perfusion and diffusion mismatch might imply injured tissue but potentially salvageable brain tissue. A mismatch may be potentially used to predict the response to treatment in-patients with late temporal lobe necrosis.