Sparse interleaved sampling for high resolution focal construct geometry X-ray tomography

We demonstrate interleaved sampling by multiplexing conical subshells within the tomosynthesis and raster scanning a phantom through a 150 kV shell X-ray beam. Each view comprises pixels sampled on a regular 1 mm grid, which is then upscaled by padding with null pixels before tomosynthesis. We show that upscaled views comprising 1% sample pixels and 99% null pixels increase the contrast transfer function (CTF) computed from constructed optical sections from approximately 0.6 line pairs/mm to 3 line pairs/mm. The driver of our method is to complement work concerning the application of conical shell beams to the measurement of diffracted photons for materials identification. Our approach is relevant to time-critical, and dose-sensitive analytical scanning applications in security screening, process control and medical imaging.

Genetic predisposition to hypertension is associated with preeclampsia in European and Central Asian women

Preeclampsia is a serious complication of pregnancy, affecting both maternal and fetal health. In genome-wide association meta-analysis of European and Central Asian mothers, we identify sequence variants that associate with preeclampsia in the maternal genome at ZNF831/20q13 and FTO/16q12. These are previously established variants for blood pressure (BP) and the FTO variant has also been associated with body mass index (BMI). Further analysis of BP variants establishes that variants at MECOM/3q26, FGF5/4q21 and SH2B3/12q24 also associate with preeclampsia through the maternal genome. We further show that a polygenic risk score for hypertension associates with preeclampsia. However, comparison with gestational hypertension indicates that additional factors modify the risk of preeclampsia.

New Service Model for Common Mental Disorders in Hong Kong: a Retrospective Outcome Study

OBJECTIVE

To review the first 8-month outcome of the Common Mental Disorder Clinic model in Hong Kong in terms of patient exit status and improvement in depressive and anxiety symptoms.

METHODS

During the first appointment, patients were interviewed by a multidisciplinary team comprising a psychiatrist, a psychiatric nurse, and an occupational therapist. A multidisciplinary case conference was conducted to discuss clinical observations, diagnosis, issues of concern, and the optimal individualised treatment plan. Low-intensity interventions by nurses and/or occupational therapists were provided, as were optional, time-limited, protocol-based interventions by clinical psychologists for those with mild to moderate depressive and anxiety symptoms. Pharmacological intervention may be used when indicated. Upon completion of the treatment plan, patients were reassessed by the treating psychiatrist. Discharge options included discharge without psychiatric follow-up, step-up to psychiatric outpatient clinics, and step-down services. The self-administered Patient Health Questionnaire-9 (PHQ-9) and Generalised Anxiety Disorder 7-item scale (GAD-7) were used to assess the past 2 weeks' depressive and anxiety symptoms, respectively, at baseline and at each session.

RESULTS

From July 2015 to February 2016, 1325 Chinese patients received the new service. Of them, 170 men and 363 women (mean age, 52.6 years) completed the treatment plan. After treatment, their mean PHQ-9 score decreased from 11.06 to 7.55 (p < 0.001), and the mean GAD-7 score decreased from 9.94 to 6.54 (p < 0.001). After treatment, 42.4% and 48.2% of the patients were within the normal range of PHQ-9 and GAD-7 scores, respectively, compared with 16.9% and 20.8% before treatment. The mean time to implementation of the individualised treatment plan was 82.33 days. Of the patients, 54.4% were discharged without any need for medical or psychiatric follow-up; 28% were stepped up to psychiatric outpatient clinics; and 17.3% were stepped down. The predictors of exit status were whether psychiatric medication was prescribed during initial intake (p = 0.011), whether psychiatric medication was prescribed at last follow-up (p < 0.001), the service period (p = 0.010), and the GAD-7 final score (p = 0.005).

CONCLUSIONS

The first 8-month outcome of the new service model was encouraging, with shortened waiting time, reduced severity of symptoms, and better exit status (high recovery and step-down rates).

Remote ischaemic conditioning for prevention of acute kidney injury after valvular heart surgery: a randomised controlled trial

BACKGROUND

Repeated remote ischaemic conditioning (RIC) during weaning from cardiopulmonary bypass and in the early postoperative period may confer protection against acute kidney injury (AKI). We evaluated the effect of repeated RIC on the incidence of AKI in patients undergoing valvular heart surgery.

METHODS

Patients were randomised into either the RIC (n=120) or control (n=124) group. A pneumatic tourniquet was placed on each patient's thigh. Upon removal of the aortic cross-clamp, three cycles of inflation for 5 min at 250 mm Hg (with 5 min intervals) were applied in the RIC group. Additionally, three cycles of RIC were repeated at postoperative 12 and 24 h. AKI was diagnosed based on the Kidney Disease: Improving Global Outcomes guideline. The incidences of renal replacement therapy, permanent stroke, sternal wound infection, newly developed atrial fibrillation, mechanical ventilation >24 h, and reoperation for bleeding during hospitalisation were recorded.

RESULTS

The incidences of AKI were not significantly different between the control (19.4%) and RIC (15.8%) groups (a difference of 3.5 percentage points; 95% confidence interval: -6.8%-13.9%; P=0.470). Perioperative serum creatinine concentrations were similar in the control and RIC groups (P=0.494). Fluid balance, urine output, blood loss, transfusion, and vasopressor/inotropic requirements were not significantly different between the groups (all P>0.05). The occurrences of a composite of morbidity and mortality endpoints were not significantly different between the control (46.0%) and RIC (39.2%) groups (a difference of 6.8 percentage points; 95% confidence interval: -6.4%-20.0%; P=0.283).

CONCLUSIONS

The results of our study do not support repeated RIC to decrease the incidence of AKI after valvular heart surgery.

CLINICAL TRIAL REGISTRATION

NCT02720549.

Preparation of “Open/closed” pores of PLGA-microsphere for controlled release of protein drug

Poly(D,L-lactic-co-glycolic acid)  has been extensively used as a controlled release carrier for drug delivery due to its good biocompatibility, biodegradability, and mechanical strength. In this study, porous PLGA microspheres were fabricated by an emulsion-solvent evaporation technique using poly ethylene glycol (PEG) as an extractable porogen and loaded with  protein (lysozyme) by suspending them in protein solution. For controlled release of protein, porous microspheres containing lysozyme were treated with water-miscible solvents in aqueous phase for production of pore-closed microspheres. The surface morphology of microspheres were investigated using scanning electron microscopy (SEM) for confirmation of its porous microstructure structure. Protein property after release was observed by enzymatic activity assay. The pore-closing process resulted in nonporous microspheres which exhibited sustained release patterns over an extended period.

Nephrolithiasis among male patients with newly diagnosed gout

INTRODUCTION

An elevated serum urate level is recognised as a cause of gouty arthritis and uric acid stone. The level of serum uric acid that accelerates kidney stone formation, however, has not yet been clarified. This study aimed to find out if a high serum urate level is associated with nephrolithiasis.

METHODS

Patients were recruited from the rheumatology clinic of Taipei City Hospital (Renai and Zhongxing branches) in Taiwan from March 2015 to February 2016. A total of 120 Chinese male patients with newly diagnosed gout and serum urate concentration of >7 mg/dL and no history of kidney stones were divided into two groups according to their serum urate level: <10 mg/dL (group 1, n=80) and ≥10 mg/dL (group 2, n=40). The mean body mass index, blood urea nitrogen level, creatinine level, urinary pH, and kidney ultrasonography were compared between the two groups.

RESULTS

There were no significant differences in blood urea nitrogen or creatinine level between the two groups. The urine pH in both groups was similar and not statistically significant. Kidney stone formation was detected via ultrasonography in 6.3% (5/80) and 82.5% (33/40) of patients in groups 1 and 2, respectively (P<0.05).

CONCLUSION

A serum urate level of ≥10 mg/dL may precipitate nephrolithiasis. Further studies are warranted to substantiate the relationship between serum urate level and kidney stone formation.

Association of bone mineral density and diabetic retinopathy in diabetic subjects: the 2008-2011 Korea National Health and Nutrition Examination Survey

Because diabetic retinopathy increases fracture risk, we studied the association between bone mineral density (BMD) and diabetic retinopathy in a nationally representative sample. A significant association between the presence of diabetic retinopathy and low BMD was observed. Therefore, diabetic retinopathy might be considered as a marker of low BMD.

INTRODUCTION

Several diabetic complications, including nephropathy, retinopathy, and peripheral neuropathy, are associated with a higher fracture risk in diabetic subjects. However, in contrast to diabetic nephropathy and peripheral neuropathy, which are associated with low bone mineral density (BMD), little is known about the association between BMD and diabetic retinopathy. The aim of the present study was to determine whether the prevalence of diabetic retinopathy is associated with BMD.

METHODS

This cross-sectional study included a nationally representative sample consisting of 4357 men aged 50 years and older and 4392 postmenopausal women who participated in the Korea National Health and Nutritional Examination Survey (KNHANES) from 2008 to 2011 and underwent BMD measurement by dual-energy X-ray absorptiometry (DXA) and diabetic retinopathy assessments using seven standard gradable photographs.

RESULTS

The diabetic women with retinopathy had lower mean BMD at all measured sites than those without retinopathy, although the BMD difference between the two groups was small (3-5 %). In addition, the diabetic women with retinopathy were 2.27 times more likely to have osteoporosis following adjustments for all clinically relevant covariates. However, the prevalence of diabetes mellitus (DM) or diabetic retinopathy was not associated with the prevalence of osteoporosis in men.

CONCLUSIONS

This study has shown that the presence of diabetic retinopathy is significantly associated with a reduced BMD and increased prevalence of osteoporosis in diabetic women.

Tuberculosis in Malaysia: predictors of treatment outcomes in a national registry

OBJECTIVES

To determine treatment outcomes and associated predictors of all patients registered in 2012 with the Malaysian National Tuberculosis (TB) Surveillance Registry.

METHODS

Sociodemographic and clinical data were analysed. Unfavourable outcomes included treatment failure, transferred out and lost to follow-up, treatment defaulters, those not evaluated and all-cause mortality.

RESULTS

In total, 21 582 patients were registered. The mean age was 42.36 ± 17.77 years, and 14.2% were non-Malaysians. The majority were new cases (93.6%). One fifth (21.5%) had unfavourable outcomes; of these, 46% died, 49% transferred out or defaulted and 1% failed treatment. Predictors of unfavourable outcomes were older age, male sex, foreign citizenship, lower education, no bacille Calmette-Guérin (BCG) vaccination scar, treatment in tertiary settings, smoking, previous anti-tuberculosis treatment, human immunodeficiency virus infection, not receiving directly observed treatment, advanced chest radiography findings, multidrug-resistant TB (MDR-TB) and extra-pulmonary TB. For all-cause mortality, predictors were similar except for rural dwelling and nationality (higher mortality among locals). Absence of BCG scar, previous treatment for TB and MDR-TB were not found to be predictors of all-cause mortality. Indigenous populations in East Malaysia had lower rates of unfavourable treatment outcomes.

CONCLUSIONS

One fifth of TB patients had unfavourable outcomes. Intervention strategies should target those at increased risk of unfavourable outcomes and all-cause mortality.

Ballistocardiogram of baby during sleep

Ballistocardiogram (BCG), which displays the mechanical activity of heart, has been a subject of interest for several years due to its advantages in taking unobtrusive physiological measurements. In the field of sleep science, researchers actively study sleep architecture and clinically apply various sleep-related conditions through BCG-derived biological information such as the heartbeat, respiration and body movements of subjects. However, most of these studies have involved only adults. This area of research may be even more important with babies to monitor their biological signals without confinement. For this reason, we developed a physiological signal monitoring bed for baby by using a load cell. Heartbeat and respiration information was assessed with average respective performance errors of 1.53% and 2.53% compared to commercial equipment. The results showed the possibility of applying BCG technology to baby. Therefore, we expect that BCG-derived signals can be extensively applied to analyze sleep architecture and clinical applications in baby as they are with adults.

Association between prolonged breastfeeding and bone mineral density and osteoporosis in postmenopausal women: KNHANES 2010-2011

This study showed that a negative correlation between duration of breastfeeding and bone mineral density (BMD) in the lumbar spine and prolonged breastfeeding is an independent risk for osteoporosis in postmenopausal women. The present study suggests that postmenopausal women with a history of prolonged breastfeeding require more careful screening for osteoporosis.

INTRODUCTION

Several studies suggest that breastfeeding and childbirth lead to maternal calcium loss and a decline in BMD. While the association between breastfeeding and BMD immediately after weaning is well-established, the effects of breastfeeding on postmenopausal women have been controversial. The aim of this study was to examine the effects of breastfeeding on bone mineral density (BMD) and the prevalence of osteoporosis in postmenopausal women.

METHODS

The present study was a cross-sectional survey based on the Korea National Health and Nutrition Examination Survey (KNHANES) 2010 and 2011 data. The association between breastfeeding and BMD and osteoporosis was examined in 1222 postmenopausal women.

RESULTS

The duration of breastfeeding and BMD in the lumbar spine showed a negative correlation. The association between duration of breastfeeding and BMD remained significant after adjustment for reproductive factors and other confounding factors (P = 0.008). However, the number of deliveries and age at the time of delivery did not correlate with BMD at any site after adjustment. Moreover, the prevalence of osteoporosis in postmenopausal women with a history of prolonged breastfeeding was significantly higher than that in women with a short history of breastfeeding (≥37 months, OR = 3.292; 95 % CI 1.485-7.299). The prevalence of lumbar spine fracture showed a significant increasing trend with the increase in the duration of breastfeeding.

CONCLUSION

Prolonged breastfeeding was significantly associated with low BMD in the lumbar spine and higher prevalence of osteoporosis. However, the number of deliveries or age at the time of childbirth did not influence BMD.

Prevalence of Psychiatric Morbidity in Chinese Subjects with Knee Osteoarthritis in a Hong Kong Orthopaedic Clinic

OBJECTIVES

To identify the prevalence and associated factors of psychiatric morbidities and to evaluate the effectiveness of the Hospital Anxiety and Depression Scale (HADS) in screening for psychiatric morbidity in patients with knee osteoarthritis in a local orthopaedic clinic.

METHODS

A cross-sectional study was conducted from October 2013 to June 2014 to examine patients with knee osteoarthritis at a specialist orthopaedic clinic. They were evaluated for psychiatric diagnoses using the Structured Clinical Interview for the DSM-IV Axis I Disorders (SCID-I). Socio-demographic and clinical characteristics were compared between patients with and without psychiatric morbidity. Patients were also assessed using the HADS with accuracy compared with the psychiatric diagnoses made by the SCID-I.

RESULTS

Of the 115 patients, 39% had current psychiatric disorders. Logistic regression analysis revealed that limitation of physical activity, perceived absence of confidant, a history of psychiatric illness, and follow-up in orthopaedic clinic for ≥ 5 years were independent factors associated with psychiatric disorders.

CONCLUSIONS

The prevalence of psychiatric morbidity in patients with knee osteoarthritis was significant. Recognition of independent associated factors can aid in early identification and intervention in patients who are at risk of developing psychiatric morbidity. The HADS is a useful means to screen for psychiatric morbidity in these patients.

Psychiatric Morbidity in Chinese Adults with Type 1 Diabetes in Hong Kong

OBJECTIVES

To determine the prevalence of psychiatric morbidity and identify the correlates, as well as to evaluate the effectiveness of the Hospital Anxiety and Depression Scale and the 12-item General Health Questionnaire to screen for psychiatric morbidity in Chinese adults with type 1 diabetes.

METHODS

Subjects were recruited from a local public diabetes specialist outpatient clinic from August 2013 to January 2014. Demographic and clinical factors were recorded. Psychiatric diagnosis was established using the Chinese-bilingual version of the Structured Clinical Interview for the DSM-IV Axis I disorders. Scores for the Hospital Anxiety and Depression Scale and the 12-item General Health Questionnaire were compared with the psychiatric diagnosis.

RESULTS

Of the 136 patients, the point prevalence of overall psychiatric, depressive, and anxiety disorders was 39.7%, 23.5%, and 25.7%, respectively. Family history of mental illness, smoking status, history of mental illness, presence of social problems, perceived absence of confidant, presence of neuropathy and hyperlipidaemia, as well as higher level of glycosylated haemoglobin were found to be the associated factors.

CONCLUSION

Psychiatric disorders were common in Chinese adults with type 1 diabetes. Finding out associated factors and using the Hospital Anxiety and Depression Scale and the 12-item General Health Questionnaire as a screening tool helped to identify patients in a diabetes clinic with psychiatric disorders.

A genetic variation in microRNA target site of KRT81 gene is associated with survival in early-stage non-small-cell lung cancer

BACKGROUND

MicroRNAs (miRNAs) have a key role in carcinogenesis through negative regulation of their target genes. Therefore, genetic variations in miRNAs or their target sites may affect miRNA-mRNA interactions, thereby result in altered expression of target genes. This study was conducted to investigate the associations between single-nucleotide polymorphisms (SNP) located in the miRNA target sites (poly-miRTSs) and survival of patients with early-stage non-small-cell lung cancer (NSCLC).

METHODS

Using public SNP database and miRNA target sites prediction program, 354 poly-miRTSs were selected for genotyping. Among these, 154 SNPs applicable to Sequenom's MassARRAY platform were investigated in 357 patients. A replication study was carried out on an independent patient population (n = 479). Renilla luciferase assay and reverse transcription-polymerase chain reaction were conducted to examine functional relevance of potentially functional poly-miRTSs.

RESULTS

Of the 154 SNPs analyzed in a discovery set, 14 SNPs were significantly associated with survival outcomes. Among these, KRT81 rs3660G>C was found to be associated with survival outcomes in the validation cohort. In the combined analysis, patients with the rs3660 GC + CC genotype had a significantly better overall survival compared with those with GG genotype [adjusted hazard ratio (aHR) for OS, 0.65; 95% confidence interval (CI) 0.50-0.85; P = 0.001]. An increased expression of the reporter gene for the C allele of rs3660 compared with the G allele was observed by luciferase assay. Consistently, the C allele was associated with higher relative expression level of KRT81 in tumor tissues.

CONCLUSION

The rs3660G>C affects KRT81 expression and thus influences survival in early-stage NSCLC. The analysis of the rs3660G>C polymorphism may be useful to identify patients at high risk of a poor disease outcome.

Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization

The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal Mendelian Long QT Syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals we identified 35 common variant QT interval loci, that collectively explain ∼8-10% of QT variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 novel QT loci in 298 unrelated LQTS probands identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode for proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies novel candidate genes for ventricular arrhythmias, LQTS,and SCD.

Congenital pseudarthrosis of the clavicle: a rare and challenging diagnosis

Congenital pseudarthrosis of the clavicle is a rare clinical entity, first described in 1910. We report on a newborn baby girl who presented with a painless lump over mid-portion of right clavicle at her routine newborn examination, which was subsequently diagnosed as a congenital pseudarthrosis. Here we explore its pathogenesis, elaborate on its differential diagnoses in paediatric patients, and comment on its distinct radiological features.

A nonintrusive temperature measuring system for estimating deep body temperature in bed

Deep body temperature is an important indicator that reflects human being's overall physiological states. Existing deep body temperature monitoring systems are too invasive to apply to awake patients for a long time. Therefore, we proposed a nonintrusive deep body temperature measuring system. To estimate deep body temperature nonintrusively, a dual-heat-flux probe and double-sensor probes were embedded in a neck pillow. When a patient uses the neck pillow to rest, the deep body temperature can be assessed using one of the thermometer probes embedded in the neck pillow. We could estimate deep body temperature in 3 different sleep positions. Also, to reduce the initial response time of dual-heat-flux thermometer which measures body temperature in supine position, we employed the curve-fitting method to one subject. And thereby, we could obtain the deep body temperature in a minute. This result shows the possibility that the system can be used as practical temperature monitoring system with appropriate curve-fitting model. In the next study, we would try to establish a general fitting model that can be applied to all of the subjects. In addition, we are planning to extract meaningful health information such as sleep structure analysis from deep body temperature data which are acquired from this system.

Imaging of thyroid carcinoma with CT and MRI: approaches to common scenarios

Computed tomography (CT) and magnetic resonance imaging (MRI) can play an important role in preoperative and post-treatment assessment of thyroid malignancy. The radiologist should be aware of the pathological behavior of thyroid carcinoma, and the characteristic imaging appearance of the primary tumor and metastases. This review describes the approach to imaging thyroid cancer on CT and MRI for four common scenarios: detection of the incidental thyroid nodule, evaluation of thyroid metastases, presurgical imaging for invasive disease, and evaluation for recurrence in the post-treatment neck.

Predictive factors for tuberculosis in patients with a TB-PCR-negative bronchial aspirate

PURPOSE

Pulmonary tuberculosis (PTB), with a tuberculosis (TB)-polymerase chain reaction (PCR)-negative bronchial aspirate (BA), but a positive culture result is often encountered in clinical practice. However, limited data are available concerning clinical judgment in patients with suspected PTB and a TB-PCR-negative BA pending culture results. The present study aimed to identify predictors for PTB in patients with a TB-PCR-negative BA.

METHODS

A retrospective study was conducted on patients who had undergone a bronchoscopy because of suspected PTB. Clinical, laboratory, and computed tomography (CT) findings were investigated in PTB patients with TB-PCR-negative but positive culture BA results, and non-PTB patients with a radiographic lesion comparable to the former.

RESULTS

Of 250 patients screened, 31 (12 %) were diagnosed with PTB by positive culture results only. Of these 31 patients, 30 (97 %) had a lesion within one-third of the hemithorax as determined by chest radiography. In the final analysis of 30 PTB and 65 non-PTB patients with comparable radiographic lesions, a positive QuantiFERON-TB Gold In-Tube (QFT) result was independently associated with an increased risk of a positive TB culture. CT findings of consolidation were a negative predictor for PTB. Patients with a negative QFT result and consolidation had a negative predictive value of 95 % for PTB, while patients with a positive QFT result and nodular CT abnormalities without consolidation had a positive predictive value of 86 % for PTB.

CONCLUSION

The simple combination of CT findings of consolidation and QFT test results may help clinicians to refine decision-making in patients with a TB-PCR-negative BA.

Fall detection algorithm for the elderly using acceleration sensors on the shoes

The rate of increase in the number of aging population in Korea is very rapid among OECD-member countries. And fall accident is one of the most common factors that threaten the health of the elderly. Therefore, it is needed to develop a fall detection system for the elderly. Most fall detection systems use accelerometers attached on the torso. And in various studies, it was verified that these systems have high sensitivity and high specificity. However, the elderly would feel uncomfortable when banding a sensor on the chest every day. Therefore, in this study, we attached an accelerometer on the shoes to detect fall in the elderly. This prototype system would be improved as a smaller, low-power system in the next study. Also, applying energy harvesting device to this shoe system is being developed to reduce the weight of battery.

MRI to differentiate benign from malignant soft-tissue tumours of the extremities: a simplified systematic imaging approach using depth, size and heterogeneity of signal intensity

OBJECTIVE

Differentiating between malignant and benign lesions on the basis of MR images depends on the experience of the radiologist. For non-experts, we aimed to develop a simplified systematic MRI approach that uses depth, size and heterogeneity on T(2) weighted MR images (T(2)WI) to differentiate between malignant and benign lesions, and evaluated its diagnostic accuracy.

METHODS

MR images of 266 patients with histologically proven soft-tissue tumours of the extremities (102 malignant, 164 benign) were analysed according to depth (superficial or deep), size (<50, ≥50 mm) and signal intensity (homogeneous or heterogeneous) on T(2)WI, to determine the ability of each to predict benign and malignant tumours. These three parameters were categorised into systematic combinations of different orders of application, and each combination was assessed for its ability to differentiate between benign and malignant lesions.

RESULTS

Univariate analysis showed that depth, size and heterogeneity on T(2)WI differed significantly between benign and malignant masses (p<0.0001 each). Multiple logistic regression analysis, however, showed that depth was not helpful in distinguishing benign from malignant lesions. The systematic combination of signal intensity, size and depth, in that order, was superior to other combinations, resulting in higher diagnostic values for malignancy, with a sensitivity of 64%, a specificity of 85%, a positive predictive value of 32%, a negative predictive value of 59% and an accuracy of 77%.

CONCLUSION

A simplified systematic imaging approach, in the order signal intensity, size and depth, would be a reference to distinguish between benign and malignant soft-tissue tumours for non-experts.

Aggravated capillary non-perfusion after intravitreal bevacizumab for macular edema secondary to systemic lupus erythematosus and anti-phospholipid syndrome

A 22-year-old female with history of systemic lupus erythematosus (SLE) was referred for evaluation of decreased visual acuity in her right eye. Her best-corrected visual acuity (BCVA) at the time of presentation was 20/160. Widespread cotton wool spots and macular edema were seen on biomicroscopy. Fluorescein angiography (FA) revealed retinal arterial and venous obstruction with capillary nonperfusion at the superotemporal retina. Antiphospholipid syndrome (APS) was diagnosed based on positive lupus anti-coagulant and ocular manifestations. Scattered laser photocoagulation was applied at the nonperfusion area but the visual acuity continued to deteriorate due to macular edema. Intravitreal bevacizumab (IVB) was administered for macular edema. One day after IVB, the BCVA decreased to count fingers. FA revealed extended non-perfusion from the superotemporal area to the posterior pole. Use of intravitreal bevacizumab for macular edema secondary to SLE or APS should be considered carefully and patients monitored closely for vascular complications.

An unusual cause of obstructive jaundice

Small-cell carcinomas of lung origin have been well characterised for their clinico-histopathological features. However, extrapulmonary small-cell carcinomas are rare, and in particular, they are extremely rare at the ampullary region. We report herein a case of small-cell carcinoma of ampulla of Vater and review its clinical, histological, and immunohistochemical features.

Hepatocarcinogenesis of regenerative and dysplastic nodules in Chinese patients

OBJECTIVES

To determine the development rate of hepatocellular carcinoma and survival of patients diagnosed to have regenerative, and low-grade and high-grade dysplastic liver nodules.

DESIGN

Retrospective descriptive study.

SETTING

Acute public hospital, Hong Kong.

PATIENTS

Patients with non-malignant liver nodules confirmed by imaging-guided liver biopsy between January 1997 and December 2008.

MAIN OUTCOME MEASURES

Rates of hepatocellular carcinoma development and survival.

RESULTS

A total of 147 patients with non-malignant liver nodules were followed up over a median duration of 29 months. The initial histological diagnosis included regenerative nodules (n=74), low-grade dysplastic nodules (n=34), and high-grade dysplastic nodules (n=39). The respective cumulative hepatocellular carcinoma development rate during the first, second, third, and fourth year were 3%, 5%, 9% and 12% for simple regenerative nodules, 29%, 35%, 38% and 44% for low-grade dysplastic nodules, and 38%, 41%, 51% and 51% for high-grade dysplastic nodules. The hepatocellular carcinoma development rate was highest in those with high-grade dysplastic nodules. Multivariate analysis showed that histological dysplastic changes were associated with increased alpha-fetoprotein levels and advanced age, which were both independent predictors of hepatocellular carcinoma development. Histological dysplastic changes, male sex, advanced age, prolonged prothrombin time, and ultrasound appearances were independent predictors of mortality.

CONCLUSION

The presence of dysplastic change in liver nodules increased the risk of hepatocellular carcinoma development and death.

Executive dysfunction and left frontal white matter hyperintensities are correlated with neuropsychiatric symptoms in stroke patients with confluent white matter hyperintensities

BACKGROUND/AIMS

This study aimed to determine the clinical and neuroimaging correlates of the presence of neuropsychiatric symptoms in stroke patients with age-related confluent white matter hyperintensities (WMH).

METHODS

The Neuropsychiatric Inventory was utilized to detect the presence of 12 symptoms. Multivariate logistic regression models were used to identify clinical and neuroimaging correlates of the presence of symptoms.

RESULTS

Seventy-seven stroke patients (mean WMH volume: 39.5 cm(3)) were recruited. Thirty patients (39%) had ≥ 1 neuropsychiatric symptom. Poor executive function was associated with the presence of any symptoms and symptoms other than depression. More severe left frontal WMH was associated with depression.

CONCLUSION

Executive dysfunction and left frontal WMH are correlated with neuropsychiatric symptoms in these patients.

Operational definitions improve reliability of the age-related white matter changes scale

BACKGROUND AND PURPOSE

Although the age-related white matter changes (ARWMC) scale has been advocated to be applicable to both MRI and CT for assessing the severity of WMC, its inter-rater reliability on CT is only fair. We aimed to operationalize the ARWMC scale and investigate the effect of this operationalization on the reliability and validity on MRI and CT.

METHODS

Operational definitions of the ARWMC scale were derived from Erkinjuntti research criteria for subcortical vascular dementia and Scheltens scale. Using original and operationalized ARWMC scale, eight observers recorded the time for rating per MRI and per CT. We investigated the inter-rater and intrarater reliability as well as validity against volume using data from 97 stroke patients.

RESULTS

Inter-rater reliability of the operationalized scale on CT (0.874, 95% confidence interval [0.780-0.934]) was better than the original scale (0.569, 95% confidence interval [0.247-0.775]). Its intrarater reliability on CT (0.869) and reliability on MRI (inter-rater: 0.860; intrarater: 0.838) was comparable with the original scale (CT intrarater: 0.750 and on MRI inter-rater: 0.845; intrarater: 0.853). The time required to administer the operationalized scale (4'2″ for MRI and 1'18″ for CT) was similar to that of the original scale (3'56″ for MRI and 1'16″ for CT). The original scale and operationalized scale also significantly correlated with WMC volume (operationalized scale ρ = 0.613, P < 0.001, original scale ρ = 0.638, P < 0.001).

CONCLUSION

Operational definitions improve the inter-rater reliability of ARWMC scale on CT, and it correlates with volumetric measurement.

Genome-wide association study of blood pressure extremes identifies variant near UMOD associated with hypertension

Hypertension is a heritable and major contributor to the global burden of disease. The sum of rare and common genetic variants robustly identified so far explain only 1%–2% of the population variation in BP and hypertension. This suggests the existence of more undiscovered common variants. We conducted a genome-wide association study in 1,621 hypertensive cases and 1,699 controls and follow-up validation analyses in 19,845 cases and 16,541 controls using an extreme case-control design. We identified a locus on chromosome 16 in the 5′ region of Uromodulin (UMOD; rs13333226, combined P value of 3.6×10⁻¹¹). The minor G allele is associated with a lower risk of hypertension (OR [95%CI]: 0.87 [0.84–0.91]), reduced urinary uromodulin excretion, better renal function; and each copy of the G allele is associated with a 7.7% reduction in risk of CVD events after adjusting for age, sex, BMI, and smoking status (H.R. = 0.923, 95% CI 0.860–0.991; p = 0.027). In a subset of 13,446 individuals with estimated glomerular filtration rate (eGFR) measurements, we show that rs13333226 is independently associated with hypertension (unadjusted for eGFR: 0.89 [0.83–0.96], p = 0.004; after eGFR adjustment: 0.89 [0.83–0.96], p = 0.003). In clinical functional studies, we also consistently show the minor G allele is associated with lower urinary uromodulin excretion. The exclusive expression of uromodulin in the thick portion of the ascending limb of Henle suggests a putative role of this variant in hypertension through an effect on sodium homeostasis. The newly discovered UMOD locus for hypertension has the potential to give new insights into the role of uromodulin in BP regulation and to identify novel drugable targets for reducing cardiovascular risk.

Hypertension is the leading contributor to global mortality with a global prevalence of 26.4% in 2000, projected to increase to 29.2% by 2025. While 50%–60% of population variation in blood pressure can be attributable to additive genetic factors, all the genetic variants robustly identified so far explain only 1%–2% of the population variance indicating the presence of additional undiscovered risk variants. Using an extreme case-control strategy, we have discovered a SNP in the promoter region of the uromodulin gene (UMOD) to be associated with hypertension (minor allele protective against hypertension). We then validated this association using large-scale population and case-control studies, where similar extreme criteria for selection of cases and controls have been used (21,466 cases and 18,240 controls). As the locus was related to uromodulin, a protein exclusively expressed in the kidneys, we show that the association is independent of renal dysfunction. We also show preliminary evidence that the SNP allele which is protective against hypertension is also protective against cardiovascular events in 26,654 Swedish subjects followed-up for 12 years. The newly discovered UMOD locus for hypertension has the potential to give unique insights into the role of uromodulin in BP regulation and to identify novel drugable targets.

Isolation and characterization of bacteriocin-producing bacteria from the gastrointestinal tract of broiler chickens for probiotic use

AIMS

To isolate and characterize the bacteriocin-producing bacteria (BPB) from the gastrointestinal tract of broiler chickens for probiotic use.

METHODS AND RESULTS

In total, 291 bacterial strains were isolated from broilers and screened for bacteriocin-producing ability. The bacteriocins produced by Enterococcus faecium SH 528, Ent. faecium SH 632 and Pediococcus pentosaceus SH 740 displayed inhibitory activity against pathogens including Clostridium perfringens and Listeria monocytogenes. Activity of the bacteriocins remained unchanged after 30 min of heat treatment at 60 degrees C or exposure to organic solvents, but diminished after treatment with proteolytic enzymes. PCR was used to detect the structural genes enterocin A and B in SH 528, enterocin L50 and P in SH 632, and pediocin PA-1 in SH 740. Most of them were resistant to 0.5% bile salts and remained viable after 2 h at pH 3.0. Ent. faecium SH 528 exhibited the highest amylase activity among the strains tested.

CONCLUSIONS

We selected Ent. faecium SH 528 and SH 632 and Ped. pentosaceus SH 740 by probiotic selection criteria including inhibition activity against pathogens.

SIGNIFICANCE AND IMPACT OF THE STUDY

The isolated BPB could potentially be used in the poultry industry as probiotics to control pathogens.

Direct comparison of optical frequency combs using a comb-injection-lock technique

This paper demonstrates a direct comparison of optical frequency combs (OFCs) with different repetition rates without a stable intermediate laser using a single-mode comb-injection-lock technique. Two OFCs based on Ti:Sapphire mode-locked lasers were compared utilizing a single-mode diode laser for the selection and the amplification of one mode of an OFC by comb-injection, which makes the direct comb comparison possible. The frequencies of the two combs were found to agree within 0.019 Hz at 352 THz with the uncertainty of 0.25 Hz (7.1 x 10(-16) ). This is one of the best results among the comparisons of combs referenced to a microwave frequency. This technique simplifies the comb comparison utilities and can be applied even when repetition rates differ.

Isolation and partial characterization of a bacteriocin produced by Pediococcus pentosaceus K23-2 isolated from Kimchi

AIMS

Screening and partial characterization of a bacteriocin produced by Pediococcus pentosaceus K23-2 isolated from Kimchi, a traditional Korean fermented vegetable.

METHODS AND RESULTS

A total of 1000 lactic acid bacteria were isolated from various Kimchi samples and screened for the production of bacteriocin. Pediocin K23-2, a bacteriocin produced by the Pediococcus pentosaceus K23-2 strain, showed strong inhibitory activity against Listeria monocytogenes. The bacteriocin activity remained unchanged after 15 min of heat treatment at 121 degrees C or exposure to organic solvents; however, it diminished after treatment with proteolytic enzymes. The bacteriocin was maximally produced at 37 degrees C, when the pH of the culture broth was maintained at 5.0 during the fermentation, although the optimum pH for growth was 7.0. The molecular weight of the bacteriocin was about 5 kDa according to a tricine SDS-PAGE analysis.

CONCLUSIONS

Pediococcus pentosaceus K23-2 isolated from Kimchi produces a bacteriocin, which shares similar characteristics to the Class IIa bacteriocins. The bacteriocin is heat stable and shows wide antimicrobial activity against Gram-positive bacteria, especially L. monocytogenes.

SIGNIFICANCE AND IMPACT OF THE STUDY

Pediocin K23-2 and pediocin K23-2-producing P. pentosaceus K23-2 could potentially be used in the food and feed industries as natural biopreservatives, and for probiotic application to humans or livestock.

Polymorphisms in the type IV collagen alpha3 gene and the risk of COPD

A number of genome-wide linkage analyses have identified the 2q33.3-2q37.2 region as the most likely to contain the genes that contribute to the susceptibility to chronic obstructive pulmonary disease (COPD). It was hypothesised that the type IV collagen alpha3 (COL4A3) gene, which is one of the genes located in the 2q33.3-2q37.2 region, may act as a low-penetrance susceptibility gene for COPD. To test this hypothesis, the association of COL4A3 -1162T>C, IVS2+12C>A, P141L, G162E, H451R, P574L and *315C>A polymorphisms with the risk of COPD was investigated in a case-control study of 311 COPD patients and 386 controls. The presence of at least one 451R allele was associated with a significantly higher risk of COPD compared with the 451 H/H genotype (adjusted odds ratio 1.48, 95% confidence interval (1.03-2.14)). When the subjects were stratified according to age and COPD severity, the 451R allele was associated with a significantly higher risk of COPD only in younger individuals with severe COPD (3.02 (1.37-6.67)). In conclusion, these findings suggest that the type IV collagen alpha3 gene contributes to the genetic susceptibility to chronic obstructive pulmonary disease.

Cell cycle arrest and lytic induction of EBV-transformed B lymphoblastoid cells by a histone deacetylase inhibitor, Trichostatin A

Latent infection of the Epstein-Barr virus (EBV) is strongly associated with the pathogenesis of several human tumor types. The restricted expression of the latent EBV antigens is critical for EBV-associated tumors to escape from immune surveillance. EBV lytic replication can be triggered by various treatments and the induced lytic genes cause strong cytotoxic T lymphocyte (CTL) responses. Histone acetylation or deacetylation is associated with chromatin remodeling and regulates gene expression. Histone deacetylase (HDAC) inhibitors affect cell cycle progression as well as gene expression in a wide variety of transformed cells. We examined whether an HDAC inhibitor, TSA, can affect cell cycle progression and induce EBV lytic replication in EBV-transformed lymphoblastoid cell lines (LCLs). TSA caused cell cycle arrest at low concentrations and induced apoptosis at higher (>300 nM) concentrations in the LCLs and EBV negative BJAB cells. To clarify the underlying mechanism of TSA-induced cell cycle arrest, expression of cell cycle regulatory factors was examined by RNase protection assay and Western blot analysis. Following TSA treatment, a reduced expression of cyclin D2 and an induction of p21 may have played an essential role for G1 arrest in LCLs, while p21 induction might have arrested BJAB cells in G1 phase. A Cdk inhibitor, p57, was increased by 300 nM TSA in both LCLs and BJAB cells, indicating its role in apoptosis. Moreover, immunofluorescene assay and Western blotting showed that TSA induced EBV lytic replication in LCL cells. These results suggest that TSA may exert an enhanced anti-tumor effect for EBV-associated tumors not only by inducing a cell cycle arrest and apoptosis, but also by triggering an EBV lytic cycle.

Functional outcome of the hand following flexor tendon repair at the 'no man's land'

PURPOSE

To evaluate the functional outcome of the hand following flexor tendon repair at 'no man's land' using 2 strands of a modified Kessler core suture and combined controlled motion rehabilitation protocol.

METHODS

Records of 31 zone-2 flexor tendon injuries in 21 digits of 16 patients between July 2000 and June 2005 were reviewed retrospectively. The injured tendons were repaired within 24 hours using 2 strands of a modified Kessler core suture, reinforced by a continuous circumferential epitendon suture. All patients completed a rehabilitation protocol that included active extension against a rubber band, passive flexion, and controlled passive extension and passive flexion exercises. Functional outcome of the fingers was assessed using the Buck-Gramcko II score. Hand grip strength, rehabilitation period, and rupture rate were also measured.

RESULTS

17 (81%) out of 21 digits in 15 out of 16 patients achieved an excellent-to-good functional grade. The remaining patient with concomitant injuries to 4 (19%) digits attained a poor functional grade, attributable to poor compliance with the rehabilitation protocol. The mean rehabilitation period was 130 days and the mean grip strength was 78% that of the uninjured side. Concomitant digital nerve injury did not adversely affect the final outcome. Only one (4.8%) patient experienced a rupture.

CONCLUSION

The surgical method and rehabilitation protocol used for zone-2 flexor tendon injury is safe and results in a reasonably good functional outcome.

Importance in optimization of multi-slice computed tomography scan protocols

This paper reviews the reasons why multi-slice CT scanners may give patients higher dose than their single-slice predecessors and discusses the type of optimization of multi-slice scan protocols that may be undertaken to keep patient doses to acceptable levels without compromising image quality. It also provides estimates of patient effective dose values and dose length products for typical procedures and briefly discusses the implication that these dose values have for the induction of possible stochastic effects.

Infectious diseases in children admitted from a residential child care centre

OBJECTIVES

To describe the pattern of infectious diseases among children admitted from a residential child care centre and to identify any unusual clusters of admissions.

DESIGN

Retrospective case review.

SETTING

Regional hospital, Hong Kong.

PATIENTS

All children from a residential child care centre aged over 28 days who were admitted from the Accident and Emergency Department to paediatric wards for infections from 1 January 1999 to 31 December 2003.

MAIN OUTCOME MEASURES

Demographic data, clinical diagnoses, infectious diseases identified, and incidence and seasonal pattern of various infections.

RESULTS

Of 267 children admitted to the hospital over the 5-year period, 221 had infectious diseases. Respiratory tract infections, viral exanthema, and gastroenteritis were present in 83.7%, 7.2%, and 5.9%, respectively. Among those with a respiratory tract infection, 22.7%, 9.2%, and 8.6% had respiratory syncytial virus, parainfluenza virus, and influenza A or B viruses, respectively. Two unusual clusters of respiratory syncytial virus and parainfluenza virus were recognised in late 2003.

CONCLUSION

Children in this residential child care centre were at risk of infectious diseases. Respiratory tract infection is the most common infectious disease in this centre. An outbreak of respiratory tract infection was recognised. Further efforts may be necessary to improve infection control measures in this setting.

Merlin facilitates ubiquitination and degradation of transactivation-responsive RNA-binding protein

The Nf2 tumor suppressor codes for merlin, a protein whose function is largely unknown. We have previously demonstrated a novel interaction between merlin and TRBP, which inhibits the oncogenic activity of TRBP. In spite of the significance of their functional interaction, its molecular mechanism still remains to be elucidated. In this report, we investigated how merlin inhibits the oncogenic activity of TRBP in association with cell growth conditions. In the human embryonic kidney 293 cell line, the level of endogenous merlin increased, whereas that of endogenous TRBP significantly decreased along with the increase in cell confluence. We demonstrated that the carboxyl-terminal region of TRBP was responsible for this phenomenon using stable cell lines expressing deletion mutants of TRBP. The overexpression of merlin decreased the protein level of TRBP, and the ubiquitin-like subdomain of merlin's FERM domain was important for this activity. We also demonstrated that TRBP is ubiquitinylated and the ubiquitinylated forms of TRBP are accumulated by ectopically expressed merlin or cell confluence in the presence of MG132, a proteasome inhibitor. Furthermore, we showed that the regulation of TRBP in response to cell confluence was abolished upon knockdown of merlin expression by specific small interfering RNA. Finally, we showed that ectopically expressed merlin restored cell-cell contact inhibition in cells stably expressing TRBP but not in TRBPDeltac. These results suggest that merlin is involved in the regulation of TRBP protein level by facilitating its ubiquitination in response to such cues as cell-cell contacts.

Spontaneous ureterocolic fistula secondary to calculous pyohydroureteronephrosis

We report a case of ureterocolic fistula secondary to urolithiasis in a 70-year-old female imaged with both CT and an antegrade nephrostogram. The ureterocolic fistula was managed with insertion of an antegrade ureteral stent.

Computed tomography manifestations of peritoneal diseases

The peritoneal cavity is a potential space that is divided by the peritoneal reflections into various complex subspaces. It can be involved in many disease processes including developmental, inflammatory, neoplastic and traumatic conditions. Computed tomography is highly sensitive and consistent in detecting peritoneal pathology. This pictorial essay aims to emphasize and illustrate the CT features of the spectrum of peritoneal diseases.

Influence of VEGF gene polymorphisms on the severity of ankylosing spondylitis

OBJECTIVES

To investigate the role of polymorphisms of the vascular endothelial growth factor (VEGF) gene in susceptibility to ankylosing spondylitis (AS), and their relationship to clinical features and radiographic severity.

METHODS

This study included 157 patients with AS and 140 healthy unrelated controls. Polymorphisms of the VEGF gene were analysed by the polymerase chain reaction (PCR)-restriction fragment length polymorphism assay and amplification refractory mutation system-PCR. Haplotypes were reconstructed using the Bayesian algorithm. Radiographic severity was assessed by the Bath Ankylosing Spondylitis Radiological Index (BASRI).

RESULTS

The genotype frequencies of the polymorphisms were in Hardy-Weinberg equilibrium. The distributions of genotypes and alleles did not differ between AS patients and controls. Among the six haplotypes reconstructed based on the tight linkage disequilibrium at positions -2578, -1154 and -634 (pairwise linkage disequilibrium coefficient, r = 0.361-0.706), no haplotype was associated with susceptibility to AS. Clinical features were analysed for the four haplotypes (CGC, CGG, AAG, AGG) which were prevalent. In carriers of the AGG haplotype, the frequency of cervical spine involvement was significantly higher (P = 0.002, P(corr) = 0.036) and that of patients showing a BASRI score >6 was also higher (P = 0.025, P(corr) = 0.45).

CONCLUSIONS

This study demonstrates that polymorphisms of the VEGF gene may contribute to disease severity in AS.

Reduction of Gstm1 Expression in the Stroke-Prone Spontaneously Hypertension Rat Contributes to Increased Oxidative Stress

Human essential hypertension is a classic example of a complex, multifactorial, polygenic disease with a substantial genetic influence in which the underlying genetic components remain unknown. The stroke-prone spontaneously hypertension rat (SHRSP) is a well-characterized experimental model for essential hypertension and endothelial dysfunction. Previous work, identified glutathione S -transferase μ type 1, a protein involved in detoxification of reactive oxygen species, as a positional and functional candidate gene. Quantitative real-time polymerase chain reaction showed a highly significant, 4-fold reduction of glutathione S -transferase μ type 1 mRNA expression in 5- and 16-week-old SHRSP compared with the congenic and normotensive Wistar Kyoto rats. This suggests that differential expression is not attributable to long-term changes in blood pressure. DNA sequencing identified one coding single nucleotide polymorphism (R202H) and multiple single nucleotide polymorphisms in the promoter region. mRNA expression changes were reflected at the protein level, with significant reductions in the SHRSP glutathione S -transferase μ type 1. Protein was colocalized with aquaporin 2 to the principle cells of the renal collecting ducts. Coupled to significant increases in nitrotyrosine levels in the kidney, this suggests a pathophysiological role of this protein in hypertension and oxidative stress. Similar processes may underlie oxidative stress in the vasculature.

Multiple microscopy modalities applied to a sea urchin tooth fragment

Two synchrotron X-ray microscopy methods, phase-contrast microradiography (the propagation method) and absorption microCT (high-resolution computed tomography or microtomography), and laser-scanning confocal microscopy (visible wavelength) were used to study a fragment of the keel of a tooth of the sea urchin Lytechinus variegatus. Stripes observed in the phase-contrast images of the fragment were also seen in confocal micrographs. MicroCT showed that the stripes were due to two parallel planar arrays of low-absorption channels within the bulk of the keel. In the phase microradiographs, maximum contrast stripes appear when a channel image from one row coincides with a channel image from the second row; otherwise, contrast is minimal. Long channels do not appear to have been observed previously in keels of sea urchin teeth.

Paraneoplastic limbic encephalitis masquerading as chronic behavioural disturbance in an adolescent girl

AIM

To describe an unusual but treatable cause of behavioural disturbance in adolescence.

METHODS

The case is reported of a 15-y-old girl presenting with acute confusion, memory problems and psychotic symptoms following an 18-mo history of change in personality, school failure and running away from home. A review of the literature is also presented.

RESULTS

Microbiology, toxicology, computed tomography and magnetic resonance imaging did not show any pathology of the central nervous system. Bilateral ovarian immature teratomas were eventually diagnosed and removed. The rapid improvement in the patient's mental and cognitive functions after corticosteroid treatment and the abnormality shown on the single photon emission computed tomography suggested a diagnosis of paraneoplastic limbic encephalitis.

CONCLUSION

Paediatricians and neurologists should be aware of this rare disease entity among the more common conditions of behavioural problems and substance abuse in adolescents.

Microarray analysis of rat chromosome 2 congenic strains

Human essential hypertension is a complex polygenic trait with underlying genetic components that remain unknown. The stroke-prone spontaneously hypertensive rat (SHRSP) is a model of human essential hypertension, and a number of reproducible blood pressure regulation quantitative trait loci have been found to map to rat chromosome 2. The SP.WKYGla2c* congenic strain was produced by introgressing a region of rat chromosome 2 from the normotensive Wistar Kyoto (WKY) strain into the genetic background of the SHRSP. Systolic and diastolic blood pressures were significantly reduced in the SP.WKYGla2c* compared with the SHRSP parental strain (198/134+/-6.1/3.3 versus 172/120+/-3.8/3.4 mm Hg; F=15.8/8.1, P=0.0009/0.013). Genome-wide microarray expression profiling was undertaken to identify differentially expressed genes among the parental SHRSP, WKY, and congenic strain. We identified a significant reduction in expression of glutathione S-transferase mu-type 2, a gene involved in the defense against oxidative stress. Quantitative reverse transcription-polymerase chain reaction relative to a beta-actin standard confirmed the microarray results with SHRSP mRNA at 8.56 x 10(-4) +/-1.6 x 10(-4) compared with SP.WKYGla2c* 3.67 x 10(-3)+/-2.8 x 10(-4) (95% CI -3.9 x 10(-3) to -1.8 x 10(-3); P=0.0034) and WKY 4.03 x 10(-3)+/-5.1 x 10(-4); (95% CI -5.4 x 10(-3) to -8.9 x 10(-4); P=0.027). We also identified regions of conserved synteny, each containing the Gstm2 gene, on mouse chromosome 3 and human chromosome 1.