Comparison of contrast-enhanced ultrasonography and MRI results obtained by expert and novice radiologists indicating short-term response after transarterial chemoembolisation for hepatocellular carcinoma.

AIM: To evaluate inter-reader agreement between novice and expert radiologists in assessing contrast-enhanced ultrasonography (CEUS) and magnetic resonance imaging (MRI) images for detecting viable tumours with different sizes after conventional transarterial chemoembolisation (cTACE). MATERIALS AND METHODS: This prospective study included patients who had less than five hepatomas and who underwent cTACE. Hepatomas with one or two feeding arteries were selected as target lesions. CEUS and MRI were performed within 1 week after cTACE to evaluate viable tumours. RESULTS: The expert group had higher kappa values in evaluating all tumour sizes via CEUS compared with MRI. The novice group had similar kappa values. In patients with tumours measuring ≤3 cm, the expert group had higher kappa values in reading CEUS compared with MRI images; however, in the novice group, the kappa value was lower in evaluating CEUS compared with MRI images. In patients with tumours measuring >3 cm, the expert and novice groups had good to excellent kappa values. The confidence level of the two groups in reading MRI images was high; however, the novice group had a lower confidence level. CONCLUSION: CEUS is a convenient, cost-effective, and easy to apply imaging tool that can help interventionists perform early detection of viable hepatocellular carcinoma post-TACE. It has a higher inter-rater agreement in interpreting CEUS images compared with MRI images among expert radiologists even when they are extremely familiar with post-cTACE MRI images. In novice radiologists, there may be a learning curve to achieve good consistency in CEUS interpretation.

A case of GNE myopathy mimicking hereditary motor neuropathy.

A 36-year-old woman who presented with upper limb distal weakness since the age of 15 years, with gradual progression to the lower limbs, is reported. Hereditary motor neuropathy was initially suspected based on distal weakness and hyporeflexia; however, whole exome sequencing accidentally revealed a compound heterozygous variant in the GNE gene, and ultrasound revealed increased homogeneous echogenicity in the involved muscles, which is characteristic of myopathic changes. Muscle magnetic resonance imaging revealed fatty infiltration in all limb muscles, sparing the triceps brachii, vastus lateralis and vastus medialis. Muscle biopsy revealed intracytoplasmic rimmed vacuole, supporting the diagnosis of GNE myopathy.

Metabolic characterization of serum from mice challenged with Orientia tsutsugamushi-infected mites.

Scrub typhus is an acute zoonosis caused by the obligate intracellular Gram-negative bacterium Orientia tsutsugamushi. To better understand the host response elicited by natural infection by chigger feeding, ICR mice were infected by Leptotrombidium chiangraiensis (Lc1) chiggers, and the metabolic profiles of their serum were examined over several time points after initiation of feeding. ICR mice were infected by either naive Lc1 chiggers (i.e. not infected by O. tsutsugamushi, NLc1) or O. tsutsugamushi-infected Lc1 chiggers (OLc1). Serum was collected from both groups of mice at 6 hours and 10 days after initiation of feeding. Metabolites were extracted from the serum and analysed by ultra performance liquid chromatography-tandem mass spectrometry. The resulting ion/chromatographic features were matched to a library of chemical standards for identification and quantification. Biochemicals that differed significantly between the experimental groups were identified using Welch's two-sample t tests; p ≤ 0.05 was considered statistically significant. A number of biochemicals linked to immune function were found to be significantly altered between mice infected by the NLc1 and OLc1 chiggers, including itaconate, kynurenine and histamine. Several metabolites linked to energy production were also found to be altered in the animals. In addition lipid and carbohydrate metabolism, bile acid and phospholipid homeostasis, and nucleotide metabolism were also found to be different in these two groups of mice. Markers of stress and food intake were also significantly altered. Global untargeted metabolomic characterization revealed significant differences in the biochemical profiles of mice infected by the NLc1 versus OLc1 chiggers. These findings provide an important platform for further investigation of the host responses associated with chigger-borne O. tsutsugamushi infections.

Physiological and pathological characterization of capsaicin-induced reversible nerve degeneration and hyperalgesia.

BACKGROUND: The study aimed to investigate the physiology, psychophysics, pathology and their relationship in reversible nociceptive nerve degeneration, and the physiology of acute hyperalgesia. METHODS: We enrolled 15 normal subjects to investigate intraepidermal nerve fibre (IENF) density, contact heat-evoked potential (CHEP) and thermal thresholds during the capsaicin-induced skin nerve degeneration-regeneration; and CHEP and thermal thresholds at capsaicin-induced acute hyperalgesia. RESULTS: After 2-week capsaicin treatment, IENF density of skin was markedly reduced with reduced amplitude and prolonged latency of CHEP, and increased warm and heat pain thresholds. The time courses of skin nerve regeneration and reversal of physiology and psychophysics were different: IENF density was still lower at 10 weeks after capsaicin treatment than that at baseline, whereas CHEP amplitude and warm threshold became normalized within 3 weeks after capsaicin treatment. Although CHEP amplitude and IENF density were best correlated in a multiple linear regression model, a one-phase exponential association model showed better fit than a simple linear one, that is in the regeneration phase, the slope of the regression line between CHEP amplitude and IENF density was steeper in the subgroup with lower IENF densities than in the one with higher IENF densities. During capsaicin-induced hyperalgesia, recordable rate of CHEP to 43 °C heat stimulation was higher with enhanced CHEP amplitude and pain perception compared to baseline. CONCLUSIONS: There were differential restoration of IENF density, CHEP and thermal thresholds, and changed CHEP-IENF relationships during skin reinnervation. CHEP can be a physiological signature of acute hyperalgesia. SIGNIFICANCE: These observations suggested the relationship between nociceptive nerve terminals and brain responses to thermal stimuli changed during different degree of skin denervation, and CHEP to low-intensity heat stimulus can reflect the physiology of hyperalgesia.

Serological evidence of high Leptospira exposure among indigenous people (Orang Asli) in Peninsular Malaysia using a recombinant antigen-based ELISA.

The lifestyles of the indigenous people (Orang Asli) of Peninsular Malaysia who traditionally live close to the forest, put them at higher risk of exposure to zoonotic diseases. Leptospirosis has recently emerged as one of the most important diseases of public health concern. Here, we aimed to obtain a baseline data on the level of Leptospira exposure among the 107 Orang Asli volunteers using a recombinant antigen-based ELISA, previously shown to have sensitivity of ~90.0% in comparison to the microscopic agglutination test (MAT). Among the Orang Asli volunteers in this study, 60.7% had IgM against Leptospira and 57.9% were antiLeptospira IgG positive. Of these seropositive individuals, 29.9% had both anti-Leptospira IgM and IgG antibodies. Age was found to be a significant predictor for exposure to Leptospira (P < 0.05) with the younger Orang Asli population more likely to be tested positive for antiLeptospira IgM. The finding of high Leptospira exposure among the Orang Asli volunteers could be due to their socio-economic practices and dependency on the forest for their livelihood. The rapid and sensitive recombinant antigen-based ELISA used in the study, could possibly complement MAT for the epidemiological surveillance of leptospirosis, especially among the underserved populations.

Clinical presentations and skin denervation in amyloid neuropathy due to transthyretin Ala97Ser.

OBJECTIVE: Familial amyloid polyneuropathy (FAP) due to amyloidogenic transthyretin (TTR) is often associated with impairment of thermonociceptive functions. This study investigated skin innervation and its clinical significance in genetically defined FAP due to a hot-spot Ala97Ser TTR mutation (Ala97Ser). METHODS: Skin biopsies were performed on the distal leg of patients with Ala97Ser, and intraepidermal nerve fiber (IENF) densities were quantified. RESULTS: There were 19 unrelated patients with Ala97Ser manifesting a late-onset (59.47 +/- 5.70 years) generalized neuropathy with disabling motor, sensory, and autonomic symptoms. Against a background of a slowly progressive course, 7 patients (36.8%) exhibited additional rapid declines in neurologic deficits, which were associated with elevation of the protein content in the CSF (p < 0.001). The IENF density was markedly reduced in Ala97Ser patients compared to age- and gender-matched controls (0.99 +/- 1.11 vs 8.31 +/- 2.87 fibers/mm, p < 0.001). Skin denervation was present in all patients and was lower in patients with a higher disability grade (0.17 +/- 0.26 vs 1.37 +/- 1.16 fibers/mm, p = 0.003). Albuminocytologic dissociation in the CSF was observed in 14 patients (73.7%), and the IENF density was negatively correlated with the CSF protein concentration (p = 0.015). CONCLUSIONS: Skin denervation was common in Ala97Ser, and degeneration of cutaneous nerve terminals was correlated with the severity of clinical phenotypes and the level of CSF protein.

Occurrence of haloacetic acids (HAAs) and trihalomethanes (THMs) in drinking water of Taiwan.

In this study, water samples were collected from 86 water treatment plants for analysis of haloacetic acids (HAAs) and trihalomethanes (THMs) from February to March, 2007 and from July to August, 2007. Both seasonal and geographical variations of disinfection by-products (DBPs) in drinking water of Taiwan were presented. The results showed that the five HAA concentrations (HAA5) were 1.0-38.9 microg/L in the winter and 0.2-46.7 microg/L in the summer; and the total THMs were ND-99.4 microg/L in the winter and ND-133.2 microg/L in the summer. For samples taken from the main Taiwan island, dichloroacetic acid (29.4-31.7%) and trichloroacetic acid (25.3-27.6%) were the two major HAA species, and trichloromethane was the major THM species (49.9-62.2%) in finished water. For water treatment plants located on the offshore islands outside of Taiwan, high bromide concentration was found in raw water, and higher percentage of brominated THMs and HAAs were formed in the overall formation. A statistically significant (P < 0.005) logarithmic linear regression model was found to be useful to describe the correlations between TTHM and HAA5 or nine HAAs (HAA5 = 1.219 x TTHM (0.754), R(2) = 0.658; HAA9 = 1.824 x TTHM (0.735), R(2) = 0.678). No apparent difference was observed for DBPs concentrations between finished water and distribution samples in this study.

Involvement of Gas7 along the ERK1/2 MAP kinase and SOX9 pathway in chondrogenesis of human marrow-derived mesenchymal stem cells.

OBJECTIVE: The growth-arrest-specific protein, Gas7, has been shown to be involved in reorganization of the cytoskeleton and for inducing changes in cell shape during cell differentiation. The goals of this study were to investigate the novel role of human Gas7 (hGas7) in chondrogenic differentiation of human mesenchymal stem cells (hMSCs) and to identify the relationship between hGas7, extracellular signal-regulated kinase (ERK1/2) and SOX9 in the chondrogenic pathway. METHODS: Bone marrow-derived hMSCs were induced to undergo chondrogenic differentiation with transforming growth factor-beta1 (TGF-beta1) in an aggregate culture system. The expression of hGas7 and SOX9 and phosphorylation of ERK1/2 at multiple time points were investigated. Chondrogenic capacity was evaluated by the size of aggregates, by glycosaminoglycan content, and by type II collagen and proteoglycan deposition after interfering with expression of hGas7, ERK1/2 or SOX9. To delineate the functional role of these genes in chondrogenesis, inhibition of individual gene's expression in hMSCs, by antisense oligonucleotides or interference RNA (siRNA), and the effect on chondrogenic differentiation were also investigated. RESULTS: Treatment of hMSCs with TGF-beta1 resulted in a transient up-regulation of hGas7b, one of the hGas7 isoforms (day 3-day 5), a transient phosphorylation of ERK1/2 (0.5-4 h) and an up-regulation of SOX9 (2 h to day 14). Transient expression of hGas7b was also detected in hMSCs by reverse transcription-polymerase chain reaction at day 2 and day 3 following TGF-beta1 treatment. Interference with hGas7b production by hGas7b-specific antisense oligonucleotide or inhibition of p-ERK with PD98059, a specific inhibitor of ERK signaling pathway, or interference with SOX9 production by SOX9 siRNA all caused adverse effects of chondrogenic differentiation of hMSCs. Meanwhile, inhibition of p-ERK or SOX9 both blocked the expression of hGas7b. However, the p-ERK and SOX9 pathway was not affected by inhibition of hGas7b. CONCLUSION: These results provide evidence that the transient expression of hGas7b, regulated by activation of ERK1/2 and SOX9 pathway, is essential for chondrogenic differentiation of hMSCs.

Painful neuropathy with skin denervation after prolonged use of linezolid.

The prolonged use of linezolid, a new antibiotic against drug-resistant gram-positive pathogens, might cause painful neuropathy. This finding raises the possibility that small-diameter sensory nerves in the skin, which are responsible for transmitting nociceptive information, might be affected. We report a 53-year-old female who developed pure small-fibre painful neuropathy (visual analogue scale, VAS = 82 on 0-100 scale) with marked skin denervation in the leg (epidermal nerve density, END = 2.32 fibres/mm, norm <5.88 fibres/mm) and significant elevation of the warm threshold in the foot (40.0 degrees C, norm <39.4 degrees C) after the use of linezolid for 6 months. Eight months after the discontinuation of linezolid, the skin became fully reinnervated (END = 9.04 fibres/mm), with disappearance of neuropathic pain (VAS = 0) and normalisation of the warm threshold (36.3 degrees C). Nerve conduction studies for large-diameter motor and sensory nerves were normal. This report documents a pure small-fibre sensory neuropathy after prolonged use of linezolid, and the relationship between skin innervation and corresponding neuropathic pain.

Transmission enhancement through a trench-surrounded nano metallic slit by bump reflectors.

We propose using a pair of bumps bordering the conventional trench-surrounded metal nano slit in order to confine the surface waves and further enhance the slit transmission. The bump height of 1.mum is larger than the depth of penetration on air side of the surface waves. The reflectivity of such bumps is larger than 95%. A very large slit transmission, which is 50% of the energy of the incident beam impinging on the entire size 13.mum of the trench-surrounded slit structure, is obtained through the metallic slit of 50nm width and 400nm depth. The bumps enhance the transmission by 1.75 fold.

Inhibition of nitric oxide can ameliorate apoptosis and modulate matrix protein gene expression in bacteria infected chondrocytes in vitro.

Bacterial infection stimulates nitric oxide (NO) production in chondrocytes. However, the role of NO in chondrocyte apoptosis after infection remains unclear. The purpose of the study was to test if inhibition of NO could ameliorate apoptosis and modulate matrix protein gene expression in bacteria-infected chondrocytes. It was shown that pre-treating chondrocytes with L-NAME (1 mM) significantly decreased the release of NO (from 72 to 14 microM) and the extent of apoptosis (from 52.9% to 18.9%). Pre-treatment with L-NAME also counteracted the bacteria-induced downregulation of Type II collagen (from 26% to 79%) and aggrecan (from 63% to 105%) mRNA levels. Inhibition of NO after the induction of infection could not decrease the extent of apoptosis and modulate matrix protein gene expression. The results of this study support the hypothesis that NO has an important role in bacteria-induced chondrocyte apoptosis. Pre-treatment but not post-treatment could ameliorate the extent of apoptosis and reestablish the cartilage matrix protein gene expression. This study suggests that in addition to NO, other mechanisms may be responsible for the sustained destruction of articular cartilage in the post-infectious arthropathy.

Identification, cloning, and expression of potential diagnostic markers for Q fever.

The clinical diagnosis of Q fever is difficult. Whole cell antigens are currently used in several serological methods, but antigens are limited due to the hazardous nature of Coxiella burnetii cultivation. In this report, we described the method of detecting immunodominant antigens of C. burnetii by using proteomic techniques with patient sera, and cloning and expressing the selected antigens using a novel vector known for its ease of expression, purification, and downstream application.

Proteomic analysis of Rickettsia prowazekii.

Rickettsia prowazekii is an obligate intracellular gram-negative bacterium. Comparative proteomics study of a virulent strain (Breinl) versus an avirulent strain (Madrid E) was performed using an integrated liquid chromatography and mass spectrometer. About 30% of predicted proteins were detected and identified. Among the detected proteins, more than 30 proteins were of unknown function in both strains. Although several proteins were detected in only one strain, the overall distribution of detected proteins in different COGs (clusters of orthologs groups) was very similar between the two strains. Functional analysis of differentially expressed proteins, either qualitatively or quantitatively, may lead to the discovery of pathogenesis-related factors.

Expression patterns of cell cycle and apoptosis-related genes in a multidrug-resistant human colon carcinoma cell line.

BACKGROUND: An in vitro multidrug resistance (MDR) system from a human colonic cancer cell line (SW620-MDR) has been established. To further study the mechanisms at molecular level and prevention of multidrug resistance in clinical practice, it was demonstrated that the expressions of several apoptosis-related and cell cycle regulator genes were changed in the cells. METHODS: A multidrug-resistant colonic cell line (SW620-MDR) was established, and the Atlas human cDNA expression array was used for studying the pattern of gene expression in this cell line. Furthermore, Northern hybridization or real-time PCR analysis confirmed the pattern of gene expression. RESULTS: In the SW620-MDR cell line the pro-apoptosis genes, CASP4, BIK, PDCD2, and TACE were expressed with decreased levels, and the antiapoptosis genes CD27-L and IGFBP2 were over-expressed. Furthermore, the cell cycle regulator genes such as CDK6, CCND1, CDC27HS, CDC16HS, Wee1Hu, MAPKK1, and IGFBP6 were expressed with decreased levels in the drug-resistant cell line. CONCLUSIONS: It is worthwhile investigating whether the differentially expressed pattern of the aforementioned genes exists in the drug-resistant cancer specimens, and to further understand their functions in the cancer drug-resistance mechanism.

Enrichment enhances the expression of sgk, a glucocorticoid-induced gene, and facilitates spatial learning through glutamate AMPA receptor mediation.

We have previously demonstrated that the serum and glucocorticoid-inducible kinase (sgk) gene plays a causal role in facilitating memory performance in rats. Environment enrichment is known to facilitate spatial learning. We therefore examined the effect of enrichment on sgk expression. We also examined the role of sgk in spatial and nonspatial learning and the regulation of sgk expression by activation of different glutamate receptors. Both real-time polymerase chain reaction and Western blot analyses revealed that enrichment training preferentially increased sgk mRNA and protein levels in the hippocampus. Transfection of sgk mutant DNA to the hippocampal CA1 area markedly impaired spatial learning, fear-conditioning learning and novel object-recognition learning in rats, but enrichment training effectively reversed these learning deficits. Meanwhile, S422A mutant DNA transfection prevented enrichment-induced spatial learning facilitation. In studying glutamate receptor regulation of sgk expression, we found that blockade of N-methyl-d-aspartate (NMDA) receptors in general, and the NR2B subunit in particular both effectively blocked enrichment-induced spatial learning facilitation, but they did not block enrichment-induced sgk expression. Upon various glutamate agonist infusions, only alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) increased sgk mRNA levels significantly in the hippocampus. Furthermore, blockade of AMPA receptors effectively blocked both enrichment-induced spatial learning facilitation and sgk expression. These results indicate that there is a dissociation between NMDA receptor activation and sgk expression. Enrichment enhanced spatial learning through both NMDA and AMPA receptor activation, whereas enrichment-induced sgk expression is specifically mediated through AMPA receptors. These results suggest that sgk could serve as a novel molecular mechanism, in addition to the NMDA receptor NR2B, underlying enrichment-induced learning facilitation.