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A prostate-targeted biopsy (TB) core is usually collected from a site where magnetic resonance imaging (MRI) indicates possible cancer. However, the extent of the lesion is difficult to accurately predict using MRI or TB alone. Therefore, we performed several biopsies around the TB site (perilesional [p] TB) and analyzed the association between the positive cores obtained using TB and pTB and the Prostate Imaging Reporting and Data System (PI-RADS) scores. This retrospective study included patients who underwent prostate biopsies. The extent of pTB was defined as the area within 10 mm of a TB site. A total of 162 eligible patients were enrolled. Prostate cancer (PCa) was diagnosed in 75.2% of patients undergoing TB, with a positivity rate of 50.7% for a PI-RADS score of 3, 95.8% for a PI-RADS score of 4, and 100% for a PI-RADS score of 5. Patients diagnosed with PCa according to both TB and pTB had significantly higher positivity rates for PI-RADS scores of 4 and 5 than for a PI-RADS score of 3 (p < 0.0001 and p = 0.0009, respectively). Additional pTB may be performed in patients with PI-RADS ≥ 4 regions of interest for assessing PCa malignancy. [ABSTRACT FROM AUTHOR]

Extended-spectrum β-lactamases (ESBLs) form the most important resistance determinants prevalent worldwide. Data on ESBL-producing Escherichia coli from poultry and livestock are scarce in India. We present data on the functional and genomic characterization of ESBL-producing E. coli obtained from poultry in India. The whole genome sequences of 28 ESBL-producing E. coli were analyzed comprising of 12 broiler chicken E. coli isolates, 11 free-range chicken E. coli isolates, and 5 human extraintestinal pathogenic E. coli. All of the 28 ESBL-producing E. coli isolates were tested for antibiotic susceptibilities, in vitro conjugation, and virulence-associated phenotypic characteristics. A total of 13 sequence types were identified from the poultry E. coli , which included globally successful sequence types such as ST117 (9%), ST131 (4.3%), and ST10 (4.3%). The most common ESBL gene detected in poultry E. coli genomes was bla CTX-M-15 (17%). Also, FIB (73%) and FII (73%) were the most common plasmid replicons identified. Conjugation experiments demonstrated 54 (7/13), 30 (3/10), and 40% (2/5) of broiler, free-range, and human ExPEC E. coli to be able to transfer their ESBL genes, respectively. The in vitro virulence-associated phenotypic tests revealed the broiler, free-range, and human ExPEC isolates to be comparable in biofilm formation, resistance to serum bactericidal activity, adherence, and invasion capabilities. Our overall results showed prevalence of virulence phenotypes among the diverse ESBL-producing E. coli from poultry; while certain E. coli clones from broiler-poultry may indeed have the potential to cause infection in humans. [ABSTRACT FROM AUTHOR]

Objective: Hydroxyapatite (HA) is used as a construction material for artificial supplementation of enamel tooth surfaces to improve oral hygiene. This study examined in vitro HA interactions with mutans streptococci (MS) and bacterial adherence to small (nanosize) crystal form of HA beads having a protean hexagonal structure. The adsorption and physical effects of HA employed in vivo is also described. Method and Materials: [3H-thymidine]-labeled streptococci were incubated with HA noncoated or coated with salivary components or salivary agglutinin peptide (SRCRP2), a receptor for streptococcal surface proteins. Bacterial adhesion activities on HA were measured by uptake of [3H-thymidine]. Application of HA paste in an individual tray was tried on the tooth surface, and its effects on the colony ratio of MS/total streptococci (TS) in saliva were analyzed by culture technique. Results: The adhesion assay showed that the binding of streptococci to HA was inhibited by coating with salivary components, whereas coating with SRCRP2 had nearly no influence on binding with or without Ca+. Further, treatment with HA decreased the adherence of Streptococci mutans to roughened enamel surfaces by one-third. In vivo application of a HA dentifrice to individual teeth demonstrated that the colony number ratio of MS/TS slowly decreased. Conclusion: MS adhesion to HA was restricted by both salivary components, except for SRCRP2, and the physical effects of HA; in addition, the material itself has a unique effect for removing MS from the oral cavity. [ABSTRACT FROM AUTHOR]

Background: The gut of human harbors diverse commensal microbiota performing an array of beneficial role for the hosts. In the present study, the major commensal gut bacteria isolated by culturing methods from 15 children of moderate income families, aged between 10 and 24 months, were studied for their response to different antibiotics, and the molecular basis of drug resistance. Results: Of 122 bacterial colonies primarily selected from Luria-Bertani agar, bacterial genera confirmed by analytical profile index (API) 20E ® system included Escherichia as the predominant (52%) organism, followed by Enterobacter (16%), Pseudomonas (12%), Klebsiella (6%), Pantoea (6%), Vibrio (3%), and Citrobacter (3%); while Aeromonas and Raoultella were identified as the infrequently occurring genera. An estimated 11 and 22% of the E. coli isolates carried virulence marker genes stx-2 and eae, respectively. Antimicrobial susceptibility assay revealed 78% of the gut bacteria to be multidrug resistant (MDR) with highest resistance to erythromycin (96%), followed by ampicillin (63%), tetracycline (59%), azithromycin (53%), sulfamethoxazole-trimethoprim (43%), cefixime (39%), and ceftriaxone (33%). PCR assay results revealed 56% of the gut bacteria to possess gene cassette Class 1 integron; while 8, 17.5 and 6% of the strains carried tetracycline resistance-related genes tetA, tetB, and tetD, respectively. The macrolide (erythromycin and azithromycin) resistance marker genes mphA, ereB, and ermB were found in 28, 3 and 5% of bacterial isolates, respectively; while 26, 12, 17, 32, 7, 4 and 3% of the MDR bacterial isolates carried the extended spectrum β-lactamase (ESBL)-related genes e.g., blaTEM, blaSHV, blaCMY-9, blaCTX-M1, blaCTX-M2, blaCMY-2 and blaOXA respectively. Majority of the MDR gut bacteria harbored large plasmids [e.g., 140 MDa (43%), 105 MDa (30%), 90 MDa (14%)] carrying invasion and related antibiotic resistance marker genes. Conclusions: Our results suggest gut of young Bangladeshi children to be an important reservoir for multi-drug resistant pathogenic bacteria carrying ESBL related genes. [ABSTRACT FROM AUTHOR]

Background: Magnetic resonance imaging (MRI) findings of pilomatricomas have yet to be determined. Purpose: To assess the correlation between MRI and pathological findings of pilomatricomas. Material and Methods: MR images were obtained on patients with histologically proven pilomatricomas using a 1.5-T MR scanner. The images were retrospectively reviewed for size, signal intensity compared with skeletal muscles, and enhancement patterns. Furthermore, we assessed the presence of a reticular appearance, a ring-like appearance, and peritumoral fat stranding. Results: We included 11 consecutive patients with 12 histologically proven pilomatricomas (3 boys/men, 8 girls/women; age range, 4-76 years; mean age, 20 years; median age, 14 years). The tumors were located in the head and neck (n = 6), upper extremities (n = 5), and lower extremities (n = 1). The maximum tumor diameter was in the range of 7-32 mm (mean, 16.5 mm). On T2-weighted (T2W) images, five tumors showed homogeneous hypointensity, whereas six showed reticular hyperintensity and one showed cystic hyperintensity. On fat-suppressed T2W images, nine tumors showed reticular hyperintensity, eight showed ring-like hyperintensity, and five showed peritumoral fat stranding. On fat-suppressed gadolinium-enhanced T1-weighted (T1W) images, one tumor showed no enhancement, whereas three showed reticular enhancement and five showed ring-like enhancement. Histologically, edematous and fibrous stroma was observed in 10 tumors, tumor capsules in 11, and inflammatory cell infiltration of the peritumoral fat tissue in nine. Conclusion: MRI features of pilomatricomas included reticular and ring-like hyperintensities on fat-suppressed T2W images and reticular and ring-like enhancement on fat-suppressed gadolinium-enhanced T1W images. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the diagnostic performance of noncontrast-enhanced magnetic resonance imaging (MRI) to grade pancreatic fibrosis and to assess hemoglobin (Hb) A1c values. Materials and Methods: Twenty-nine consecutive patients with pancreatic or biliary malignancy who underwent pancreatectomy were evaluated. Patients were classified into three groups: HbA1c < 5.7 (group 1), 5.7 ≤ HbA1c < 6.5 (group 2), and HbA1c ≥ 6.5 (group 3). MRI of the pancreas was performed using a 1.5T MR system. The pancreas-to-muscle signal intensity ratio (SIR) on in- and opposed-phase T1 -, T2 -, and diffusion-weighted images, as well as the apparent diffusion coefficient were calculated. MRI measurements, degrees of pancreatic fibrosis, and HbA1c values were compared using multiple regression analysis and Kruskal-Wallis test. Results: The pancreatic fibrosis grade was negatively correlated with the SIR on in-phase T1 -weighted images (r = -0.67, P = 0.0002). The pancreatic fibrosis grade and HbA1c value were negatively correlated with the SIR on opposed-phase T1 -weighted images (r = -0.47, P = 0.019 and r = -0.51, P = 0.0089, respectively). SIRs on in- and opposed-phase T1 -weighted images were significantly lower in group 3 than in groups 1 and 2 (P < 0.05). Conclusion: The pancreas-to-muscle SIRs on in- and opposed-phase T1 -weighted images could be a potential biomarker for pancreatic fibrosis and elevated HbA1c values. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the contributory value of Fluorine-18 fluorodeoxyglucose (F-18 FDG) positron emission tomography/computed tomography (PET/CT) in the prediction of lymphovascular tumor invasion in patients with lung adenocarcinoma.Materials and Methods: We evaluated F-18 FDG-PET/CT images in 84 patients with histopathologically proven lung adenocarcinoma (37 men and 47 women, age range 39-83 years, mean age 67.0 ± 8.9 years). The maximum standardized uptake values (SUVmax) of the carcinomas were measured from the PET images. The Mann-Whitney U test was conducted to compare the median SUVmax between the tumor groups with and without lymphovascular invasion. In the subgroup patients with no lymph-node metastasis, we also compared the median SUVmax between the tumor groups with and without lymphatic invasion.Results: The tumors with lymphovascular invasion had a significantly (P < 0.0001) greater median SUVmax than those without invasion. In the subgroup patients with no lymph-node metastasis, the median SUVmax was higher in tumors with lymphatic invasion than those without (P = 0.0004). The sensitivity, specificity, and area under the receiver operating characteristic curve for the detection of tumors with lymphovascular invasion were 89, 75 %, and 0.82, respectively, with a cutoff SUVmax value of 2.32.Conclusion: The SUVmax of lung adenocarcinoma is a potential imaging biomarker for predicting tumor lymphovascular invasion. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the feasibility of diffusion kurtosis (DK) imaging of the pancreas for the assessment of hemoglobin (Hb) A1c values.Materials and Methods: Our Institutional Review Board approved this prospective study and written informed consent was obtained. In all, 102 consecutive patients with suspected pancreatic disease underwent magnetic resonance imaging (MRI), including DK imaging. Patients were classified into three groups according to American Diabetes Association criteria: HbA1c < 5.7% (group 1), 5.7% ≤ HbA1c < 6.5% (group 2), and HbA1c ≥ 6.5% (group 3). Mean kurtosis (MK) and apparent diffusion coefficient (ADC) of pancreatic parenchyma were computed. MRI measurements and HbA1c values were then compared.Results: HbA1c values positively correlated with MK (r = 0.66, P < 0.0001). Group 3 was significantly (P < 0.05) higher (P < 0.05) in MK than groups 1 and 2. The sensitivity, specificity, and area under the ROC curve of the MK for the detection of group 3 were 90%, 88%, and 0.92, respectively.Conclusion: The MK measurement on DK imaging of the pancreas could be a potential biomarker for assessing HbA1c level. [ABSTRACT FROM AUTHOR]

Objective: To assess prospectively the efficacy of arterial spin labelling (ASL) against conventional and diffusion-weighted (DW) MR imaging for differentiating parotid gland tumours.Methods: We included 10 pleomorphic adenomas, 12 Warthin's tumours, and nine malignant tumours of the parotid glands. Only tumours larger than 10 mm were included in this study. All parotid gland tumours underwent T1-weighted, T2-weighted, DW, and ASL imaging. Tumour-to-parotid gland signal intensity ratios (SIRs) and apparent diffusion coefficients (ADCs) of solid components were correlated with these pathologies.Results: SIRs on T2-weighted images and ADCs were higher in pleomorphic adenomas than in Warthin's tumours (p < .01) and malignant tumours (p < .01). SIRs on ASL were higher in Warthin's tumours than in pleomorphic adenomas (p < .01) and malignant tumours (p < .05). Az value of SIRs on ASL for differentiating Warthin's tumours from the other pathologies was 0.982. The sensitivity, specificity, and accuracy of SIRs on ASL for the diagnosis of Warthin's tumours at an optimal SIR threshold of over 8.70 were 91.7%, 94.7%, and 93.5%, respectively.Conclusions: ASL with SIR measurements could non-invasively evaluate tumour blood flow of parotid gland tumours and differentiate Warthin's tumours from pleomorphic adenomas and malignant tumours.Key Points: • ASL non-invasively evaluates tumour blood flow of parotid gland tumours • ASL differentiates Warthin's tumours from pleomorphic adenomas and malignant tumours • ASL cannot differentiate between pleomorphic adenomas and malignant tumours. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the usefulness of Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18-F FDG-PET/CT) in the prediction of Fuhrman pathological grades of renal clear cell carcinoma (cRCC). Methods: This retrospective study was approved by our institutional review board, and written informed consent was waived. Thirty-one patients with pathologically proven cRCC underwent 18-F FDG-PET/CT for tumour staging. Maximum standardized uptake value of cRCC (tumour SUV) and mean SUV of the liver and spleen (liver and spleen SUV) were measured by two independent observers. Tumour SUV, tumour-to-liver SUV ratio, and tumour-to-spleen SUV ratio were correlated with the pathological grades. Results: Logistic analysis demonstrated that only the tumour-to-liver SUV ratio was a significant parameter for differentiating high-grade (Fuhrman grades 3 and 4) tumours from low-grade (Fuhrman grades 1 and 2) tumours ( P = 0.007 and 0.010 for observers 1 and 2, respectively). Sensitivity, specificity, and positive and negative predictive values for detecting tumours of Fuhrman grades 3 and 4 were 64, 100, 100, and 77 %, respectively, for observer 1, and 79, 88, 85, and 83 %, respectively, for observer 2. Conclusions: The tumour-to-liver SUV ratio with 18-F FDG-PET/CT appeared to be a valuable imaging biomarker in the prediction of high-grade cRCC. Key Points: • Tumour SUV was correlated with the Fuhrman grades. • High-grade tumours have significantly higher SUV than low-grade tumours. • Tumour-to-liver SUV ratio is useful in the prediction of high-grade cRCC. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the study was to evaluate the characteristic imaging features and performance of prenatal magnetic resonance (MR) imaging in the diagnosis of placental invasion. Methods: This retrospective study was approved by our institutional review board and written informed consent was waived. Twenty-eight patients (age range 26-39 years; mean age, 33.8 ± 3.1 years) with suspected placental invasion underwent prenatal MR imaging, including 7 patients with placental invasion and 21 without. Two radiologists assessed the presence of seven previously described MR imaging findings associated with placental invasion. Sensitivity, specificity, positive and negative predictive values, and accuracy were calculated. The diagnostic performance was also determined by a receiver-operating-characteristic curve analysis. Results: Three MR imaging findings (uterine bulging, heterogeneous signal intensity in the placenta on T2-weighted images, and hypointense intraplacental bands on T2-weighted images) were significantly more common in patients with placental invasion than in those without ( P = 0.020-0.023). The presence of at least two of these three imaging findings yielded a sensitivity, specificity, positive and negative predictive values, and accuracy of 100, 86, 67, 95, and 89%, respectively. Conclusions: The presence of at least two of the three characteristic prenatal MR imaging findings strongly supports a diagnosis of placental invasion. [ABSTRACT FROM AUTHOR]

The article examines the use of diffusion-weighted (DW) imaging to identify between benign and malignant liver lesions. It states the development of intravoxel incoherent motion (IVIM) imaging to evaluate the microscopic translational motions in magnetic resonance (MR) images. It also emphasizes the demonstration of true molecular diffusion and microcirculation through blood perfusion.

Introduction: The purpose of this study was to assess computed tomography (CT) and magnetic resonance (MR) imaging findings of salivary gland tumors of the parotid gland with emphasis on intratumoral cystic components. Methods: Seventy-two histopathologically confirmed salivary gland tumors of the parotid gland (44 benign and 28 malignant), which underwent both CT and MR imaging including contrast-enhanced study, were included in this study. We retrospectively reviewed images for the presence, number, occupying rate, margin characteristics, distribution, and predominant MR signal intensity of intratumoral cystic components. Results: The prevalence of cystic components was greater in malignant than benign tumors (79 vs. 50 %, p < 0.05). The number and occupying rate were similar between benign and malignant tumors. The irregular margins were more frequent in malignant than benign tumors (73 vs. 27 %, p < 0.01). The frequency of eccentric location was greater in benign than malignant tumors (91 vs. 55 %, p < 0.01), whereas the frequency of centric location was greater in malignant than benign tumors (32 vs. 0 %, p < 0.01). On T1-weighted images, the frequency of hyperintensity was greater in benign than malignant tumors (50 vs. 9 %, p < 0.01), whereas that of isointensity was greater in malignant than benign tumors (50 vs. 0 %, p < 0.01). Multiple logistic regression analysis showed that the absence of irregular margins of cystic components only was significantly correlated with the presence of benign salivary gland tumors ( p < 0.01). Conclusion: Imaging features of intratumoral cystic components may help to differentiate benign from malignant tumors of the parotid salivary gland. [ABSTRACT FROM AUTHOR]

Objectives: To determine the optimal iodine mass (IM) to achieve a 50-HU increase in hepatic attenuation for the detection of liver metastasis based on total body weight (TBW) or body surface area (BSA) at 80-kVp computed tomography (CT) imaging of the liver.Methods: One-hundred and fifty patients who underwent contrast-enhanced CT at 80-kVp were randomised into three groups: 0.5 gI/kg, 0.4 gI/kg and 0.3 gI/kg. Portal venous phase images were evaluated for hepatic parenchymal enhancement (∆HU) and visualisation of liver metastasis. Iodine mass per BSA (gI/m(2)) calculated in individual patients were evaluated.Results: Mean ∆HU for the 0.5 gI/kg group (84.2 HU) was higher than in the 0.4 gI/kg (66.1 HU) and 0.3 gI/kg (53.7 HU) groups (P < 0.001). Linear correlation equations between ∆HU and IM per TBW or BSA are ∆HU = 7.0 + 153.0 × IM/TBW (r = 0.73, P < 0.001) and ∆HU = 11.4 + 4.0 × IM/BSA (r = 0.75, P < 0.001), respectively. The three groups were comparable for the visualisation of hepatic metastases.Conclusions: The iodine mass to achieve a 50-HU increase in hepatic attenuation at 80-kVp CT was estimated to be 0.28 gI/kg of body weight or 9.6 gI/m(2) of body surface area.Key Points: • Hepatic enhancement is expressed as ∆HU = 7.0 + 153.0 × IM [g]/TBW [kg]. • Hepatic enhancement is expressed as ∆HU = 11.4 + 4.0 × IM [g]/BSA [m(2)]. • Essential iodine dose at 80-kVp CT was 0.28 gI/kg or 9.6 gI/m(2). [ABSTRACT FROM AUTHOR]

The seventh cholera pandemic caused by Vibrio cholerae O1 El Tor (ET) has been superseded in Asia and Africa by altered ET possessing the cholera toxin (CTX) gene of classical (CL) biotype. The CL biotype of V. cholerae was isolated, along with prototypic and altered ET, during the 1991 cholera epidemic in Mexico and subsequently remained endemic until 1997. Microbiological, molecular, and phylogenetic analyses of clinical and environmental V. cholerae isolated in Mexico between 1998 and 2008 revealed important genetic events favoring predominance of ET over CL and altered ET. V. cholerae altered ET was predominant after 1991 but not after 2000. 7. cholerae strains isolated between 2001 and 2003 and a majority isolated in 2004 lacked CTX prophage (Φ) genes encoding CTX subunits A and B and repeat sequence transcriptional regulators of ET and CL biotypes: i.e., CTXΦ-. Most CTXΦ-V. cholerae isolated in Mexico between 2001 and 2003 also lacked toxin coregulated pili tcpA whereas some carried either tcpAET or a variant tcpA with noticeable sequence dissimilarity from tcpACL. The tcpA variants were not detected in 2005 after CTXΦ+ ET became dominant. All clinical and environmental V. cholerae 01 strains isolated during 2005-2008 in Mexico were CTXΦ+ ET, carrying an additional truncated CTXΦ instead of RS1 satellite phage. Despite V. cholerae CTXΦ- ET exhibiting heterogeneity in pulsed-field gel electrophoresis patterns, CTXΦ+ ET isolated during 2004-2008 displayed homogeneity and clonal relationship with V. cholerae ET N16961 and V. cholerae ET isolated in Peru. [ABSTRACT FROM AUTHOR]

In Vibrio cholerae, 41 chitin-inducible genes, including the genes involved in natural competence for DNA uptake, are governed by the orphan two-component system ( TCS) sensor kinase ChiS. However, the mechanism by which ChiS controls the expression of these genes is currently unknown. Here, we report the involvement of a novel transcription factor termed ' TfoS' in this process. TfoS is a transmembrane protein that contains a large periplasmic domain and a cytoplasmic AraC-type DNA-binding domain, but lacks TCS signature domains. Inactivation of tfoS abolished natural competence as well as transcription of the tfoR gene encoding a chitin-induced small RNA essential for competence gene expression. A TfoS fragment containing the DNA-binding domain specifically bound to and activated transcription from the tfoR promoter. Intracellular TfoS levels were unaffected by disruption of chiS and coexpression of TfoS and ChiS in Escherichia coli recovered transcription of the chromosomally integrated tfoR:: lacZ gene, suggesting that TfoS is post-translationally modulated by ChiS during transcriptional activation; however, this regulation persisted when the canonical phosphorelay residues of ChiS were mutated. The results presented here suggest that ChiS operates a chitin-induced non-canonical signal transduction cascade through TfoS, leading to transcriptional activation of tfoR. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the best standardized uptake value (SUV) index for differentiation of adrenal metastases from adrenocortical adenomas using 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT). Materials and Methods: A total of 129 patients (82 males and 47 females; mean age 65.4 years) with extra-adrenal primary malignancies who had known or suspected adrenal lesions underwent FDG PET/CT examinations for detection, staging, re-staging, or recurrence of tumor. Among these patients, 45 adrenal lesions (22 adenomas and 23 metastases) in 41 patients were evaluated. The maximum SUVs for adrenal lesions (adrenal SUVmax) and mean liver and spleen SUVs were recorded, and the ratio of the adrenal SUVmax to the mean liver SUV (adrenal-to-liver SUV ratio) and that of the adrenal SUVmax to the mean spleen SUV (adrenal-to-spleen SUV ratio) were obtained. Diagnostic performances for the adrenal SUVmax, adrenal-to-liver SUV ratio, and adrenal-to-spleen SUV ratio were compared. Results: The mean adrenal SUVmax, adrenal-to-liver SUV ratio, and adrenal-to-spleen SUV ratio were higher for adrenal metastases (8.4 ± 3.8, 3.0 ± 1.3, and 4.0 ± 1.9, respectively) than for adrenocortical adenomas (2.9 ± 1.0, 0.9 ± 0.3, and 1.3 ± 0.3, respectively) (P < 0.001). The area under the curve was higher for the adrenal-to-liver SUV ratio (0.99) than for the adrenal SUVmax (0.96) and adrenal-to-spleen SUV ratio (0.98). In the differentiation of adrenocortical adenomas and adrenal metastases, an adrenal-to-liver SUV ratio cutoff value of 1.37 yielded a sensitivity of 96% and specificity of 100%. Conclusion: In FDG PET/CT analysis, the adrenal-to-liver SUV ratio had a greater ability to differentiate adrenocortical adenomas and adrenal metastases than did the adrenal SUVmax or adrenal-to-spleen SUV ratio. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the best standardized uptake value (SUV) index for differentiation of adrenal metastases from adrenocortical adenomas using 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT). Materials and methods: A total of 129 patients (82 males and 47 females; mean age 65.4 years) with extra-adrenal primary malignancies who had known or suspected adrenal lesions underwent FDG PET/CT examinations for detection, staging, re-staging, or recurrence of tumor. Among these patients, 45 adrenal lesions (22 adenomas and 23 metastases) in 41 patients were evaluated. The maximum SUVs for adrenal lesions (adrenal SUVmax) and mean liver and spleen SUVs were recorded, and the ratio of the adrenal SUVmax to the mean liver SUV (adrenal-to-liver SUV ratio) and that of the adrenal SUVmax to the mean spleen SUV (adrenal-to-spleen SUV ratio) were obtained. Diagnostic performances for the adrenal SUVmax, adrenal-to-liver SUV ratio, and adrenal-to-spleen SUV ratio were compared. Results: The mean adrenal SUVmax, adrenal-to-liver SUV ratio, and adrenal-to-spleen SUV ratio were higher for adrenal metastases (8.4 ± 3.8, 3.0 ± 1.3, and 4.0 ± 1.9, respectively) than for adrenocortical adenomas (2.9 ± 1.0, 0.9 ± 0.3, and 1.3 ± 0.3, respectively) ( P < 0.001). The area under the curve was higher for the adrenal-to-liver SUV ratio (0.99) than for the adrenal SUVmax (0.96) and adrenal-to-spleen SUV ratio (0.98). In the differentiation of adrenocortical adenomas and adrenal metastases, an adrenal-to-liver SUV ratio cutoff value of 1.37 yielded a sensitivity of 96 % and specificity of 100 %. Conclusion: In FDG PET/CT analysis, the adrenal-to-liver SUV ratio had a greater ability to differentiate adrenocortical adenomas and adrenal metastases than did the adrenal SUVmax or adrenal-to-spleen SUV ratio. [ABSTRACT FROM AUTHOR]

Objective: To compare total body weight (TBW), lean body weight (LBW) and body surface area (BSA) for the adjustment of the iodine dose required for contrast-enhanced multi-detector computed tomography (MDCT) of the aorta and the liver. Methods: One hundred and three patients undergoing MDCT of the abdomen were randomised into three groups: the TBW group receiving 0.6 g iodine/kg of TBW ( n = 33), the LBW group receiving 0.75 g iodine/kg of LBW ( n = 35) and the BSA group receiving 22 g iodine/m ( n = 35). ∆HU (increases in CT value) per gram of iodine (∆HU/g) and adjusted maximum hepatic enhancement (adjusted MHE; ∆HU/[g iodine/kg]) correlated with three groups using linear regressions. Results: Correlation coefficients of ∆HU/g were 0.67 (TBW), 0.86 (LBW) and 0.85 (BSA) for the aorta, and 0.74 (TBW), 0.77 (LBW) and 0.84 (BSA) for the liver. Adjusted MHE was constant at 70.2 with LBW and at 2.69 with BSA, but correlated positively with TBW ( r = 0.58, P < 0.001). Conclusion: Iodine load may need to be tailored by LBW or BSA in contrast enhanced MDCT of the abdomen. BSA is a simple and feasible index for the determination of iodine dose in individual patients. Key Points: • Optimisation of enhancement is very important for high quality MDCT. • Iodine dose is best adjusted according to LBW or BSA. • BSA may be adopted because calculation is simple. • Iodine dose of 0. 712 g/ kg LBW/ 18. 6 g/ m BSA gives 50 HU hepatic enhancement. [ABSTRACT FROM AUTHOR]

ABSTRACT Twelve Vibrio cholerae isolates with genes for a type III secretion system (T3SS) were detected among 110 environmental and 14 clinical isolates. T3SS-related genes were distributed among the various serogroups and pulsed-field gel electrophoresis of NotI-digested genomes showed genetic diversity in these strains. However, the restriction fragment length polymorphism profiles of the T3SS-related genes had similar patterns. Additionally, naturally competent T3SS-negative V. cholerae incorporated the ca. 47 kb gene cluster of T3SS, which had been integrated into a site on the chromosome by recombination. Therefore, it is suggested that horizontal gene transfer of T3SS-related genes occurs among V. cholerae in natural ecosystems. [ABSTRACT FROM AUTHOR]

The purpose of this pictorial review is to discuss the usefulness and limitations of diffusion-weighted (DW) MR imaging of the liver, demonstrating DW images of a variety of focal hepatic diseases. We include hepatocellular carcinoma, borderline-lesions in cirrhosis, metastasis, cavernous hemangioma, cyst, focal nodular hyperplasia, hepatic adenoma, abscess, and hematoma. DW imaging is an important supplementary sequence of routine MR imaging protocols of the liver. Radiologists need to understand its usefulness and limitations in the detection and characterization of benign and malignant focal hepatic diseases. [ABSTRACT FROM AUTHOR]

Background: The diverse bacterial communities colonizing the gut (gastrointestinal tract) of infants as commensal flora, which play an important role in nutrient absorption and determining the state of health, are known to alter due to diarrhea. Method: Bacterial community dynamics in children suffering from cholera and during recovery period were examined in the present study by employing metagenomic tool, followed by DNA sequencing and analysis. For this, bacterial community DNA was extracted from fecal samples of nine clinically confirmed cholera children (age 2-3 years) at day 0 (acute cholera), day 2 (antibiotic therapy), day 7 and, and day 28, and the variable region of 16S rRNA genes were amplified by universal primer PCR. Results: 454 parallel sequencing of the amplified DNA followed by similarity search of the sequenced data against an rRNA database allowed us to identify V. cholerae, the cause of cholera, in all nine children at day 0, and as predominant species in six children, accounting for 35% of the total gut microbiota on an average in all the nine children. The relative abundance (mean ± sem %) of bacteria belonging to phyla Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria, was 55 ± 7, 18 ± 4, 13 ± 4, and 8 ± 4, respectively, at day 0, while these values were 12 ± 4, 43 ± 4, 33 ± 3, and 12 ± 2, respectively, at day 28. As antibiotic therapy began, V. cholerae count declined significantly (p< 0.001) and was found only in four children at day 2 and two children at day 7 with the relative abundance of 3.7% and 0.01%, respectively, which continued up to day 28 in the two children. Compared to acute cholera condition (day 0), the relative abundance of Escherichia coli, Enterococcus, and Veillonella increased at day 2 (antibiotic therapy) while Bifidobacterium, Bacteroides, and Ruminococcus decreased. Conclusion: Cholera results expulsion of major commensal bacteria of phyla Bacteroidetes, Firmicutes, and Actinobacteria, and increase of harmful Proteobacteria to colonize the gut during acute and convalescence states. The observed microbiota disruption might explain the prevalent malnutrition in children of Bangladesh where diarrheal diseases are endemic. [ABSTRACT FROM AUTHOR]

Enterohemorrhagic Escherichia coli (EHEC) Sakai strain encodes two homologous type III effectors, EspO1-1 and EspO1-2. These EspO1s have amino acid sequence homology with Shigella OspE, which targets integrin-linked kinase to stabilize formation of focal adhesions (FAs). Like OspE, EspO1-1 was localized to FAs in EHEC-infected cells, but EspO1-2 was localized in the cytoplasm. An EHEC ΔespO1-1ΔespO1-2 double mutant induced cell rounding and FA loss in most of infected cells, but neither the ΔespO1-1 nor ΔespO1-2 single mutant did. These results suggested that EspO1-2 functioned in the cytoplasm by a different mechanism from EspO1-1 and OspE. Since several type III effectors modulate Rho GTPase, which contributes to FA formation, we investigated whether EspO1-2 modulates the function of these type III effectors. We identified a direct interaction between EspO1-2 and EspM2, which acts as a RhoA guanine nucleotide exchange factor. Upon ectopic co-expression, EspO1-2 co-localized with EspM2 in the cytoplasm and suppressed EspM2-mediated stress fiber formation. Consistent with these findings, an ΔespO1-1ΔespO1-2ΔespM2 triple mutant did not induce cell rounding in epithelial cells. These results indicated that EspO1-2 interacted with EspM2 to regulate EspM2-mediated RhoA activity and stabilize FA formation during EHEC infection. [ABSTRACT FROM AUTHOR]

Purpose: To determine if a 20 % reduction in the contrast material dose is acceptable in the CT evaluation of patients with head and neck malignancy. Materials and methods: Sixty consecutive patients (mean age 67 years) with head and neck malignancy underwent contrast-enhanced CT according to two different protocols: protocol A (80 mL of contrast material administered at an injection rate of 1.5 mL/s) and protocol B (100 mL at 1.9 mL/s). The enhancement of anatomical structures and detectability of metastatic nodes were compared between the two protocols. Pathologic analysis of the surgical resection served as the reference standard. Results: CT numbers of the anatomical structures were not significantly different between the two protocols. Mean sensitivity (64 and 77 % for protocols A and B, respectively), specificity (78 and 84 %), and accuracy (74 and 83 %) tended to be higher for protocol B than for A, but no significant difference was found. Conclusion: Reducing the contrast material dose by 20 % did not significantly impair the enhancement of anatomical structures or the detection of metastatic cervical lymph nodes. Radiologists should therefore consider reducing the contrast material dose used in head and neck CT. [ABSTRACT FROM AUTHOR]

We identified 131 strains of Vibrio fluvialis among 400 nonagglutinating Vibrio spp. isolated from patients with diarrhea in Kolkata, India. For 43 patients, V. fluvialis was the sole pathogen identified. Most strains harbored genes encoding hemolysin and metalloprotease; this finding may contribute to understanding of the pathogenicity of V. fluvialis. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate whether incorporation of a 3D turbo spin-echo sequence during T2-weighted MR imaging improves the detection of focal hepatic lesions by 3T MR imaging.Materials and Methods: Seventy-nine consecutive patients including 67 patients with 62 malignant and 71 benign lesions and 12 patients having no hepatic lesion underwent respiratory-triggered fat-suppressed axial T2-weighted turbo spin-echo imaging using two-dimensional (2D-TSE) and 3D (3D-TSE) sequences. Coronal multiplanar reformatted images (MPR-3D-TSE) were generated from 3D-TSE images. Breath-hold fat-suppressed 2D axial T2-weighted half-Fourier turbo spin-echo (HF-2D-TSE) images were combined for reading. Two independent radiologists reviewed three imaging sets, (1) 2D-TSE and HF-2D-TSE, (2) 3D-TSE and HF-2D-TSE, and (3) 3D-TSE, HF-2D-TSE and MPR-3D-TSE, for detection of malignant and benign lesions. Lesion-to-liver contrast ratio (CR) and the conspicuity of anatomical boundaries were assessed.Results: For benign lesions, lesion-to-liver CRs with 3D-TSE (2.77 ± 1.91, p = .0002) and MPR-3D-TSE (2.47 ± 1.42, p = .012) were higher than with 2D-TSE (2.13 ± 1.80). Sensitivity for lesions of ≤ 10-mm was higher with 3D-TSE (86 %, p = .0039) and MPR-3D-TSE (84 %, p = .0078) than with 2D-TSE (72 %). However, the edge of left lateral lobe was less conspicuous with 3D-TSE (p < .0001) and MPR-3D-TSE (p = .0003) than with 2D-TSE because of susceptibility artifacts.Conclusion: Incorporation of 3D T2-weighted sequence may incrementally improve the detection of focal hepatic lesions. [ABSTRACT FROM AUTHOR]

Two patients with gastric carcinoma underwent CT colonography (CTC) for preoperative work-up. Although no obvious peritoneal nodules were seen on axial CT images, colonic wall deformities were noted on three-dimensional (3D) air images. Multiplanar-reformatted images revealed corresponding colonic wall thickening at the deformities, and in addition, dense cordlike structures connecting the primary gastric cancer and colonic wall thickening were also observed. In one patient, cordlike indurations consistent with peritoneal invasion were found to connect the primary gastric cancer, gastrocolic ligament, and transverse mesocolon during exploratory surgery, and in the other, colonic scars consistent with peritoneal invasion after chemotherapy were observed. These observations suggest that CTC could be of potential use for the differentiation of transperitoneal colonic invasion and gastric cancer. [ABSTRACT FROM AUTHOR]

Background: Shigellosis is a major public health concern worldwide, especially in developing countries. It is an acute intestinal infection caused by bacteria of the genus Shigella, with a minimum infective dose as low as 10-100 bacterial cells. Increasing prevalence of Shigella sonnei as the etiologic agent of shigellosis in Malaysia has been reported. As there is limited information on the genetic background of S. sonnei in Malaysia, this study aimed to characterize Malaysian S. sonnei and to evaluate the prospect of using multilocus variable-number tandem-repeat (VNTR) analysis (MLVA) for subtyping of local S. sonnei. Methods: Forty non-repeat clinical strains of S. sonnei isolated during the years 1997-2000, and 2007-2009 were studied. The strains were isolated from stools of patients in different hospitals from different regions in Malaysia. These epidemiologically unrelated strains were characterized using biotyping, antimicrobial susceptibility testing, pulsed-field gel electrophoresis (PFGE) and MLVA. Results: The two biotypes identified in this study were biotype a (n = 29, 73%) and biotype g (n = 11, 27%). All the 40 strains were sensitive to kanamycin, ceftriaxone and ciprofloxacin. Highest resistance rate was observed for streptomycin (67.5%), followed by tetracycline (40%) and trimethoprim-sulfamethoxazole (37.5%). All the S. sonnei biotype g strains had a core resistance type of streptomycin--trimethoprim-sulfamethoxazole--tetracycline whereas the 29 biotype a strains were subtyped into eight resistotypes. All the strains were equally distinguishable by PFGE and MLVA. Overall, PFGE analysis indicated that S. sonnei biotype a strains were genetically more diverse than biotype g strains. Cluster analysis by MLVA was better in grouping the strains according to biotypes, was reflective of the epidemiological information and was equally discriminative as PFGE. Conclusions: The S. sonnei strains circulating in Malaysia throughout the period studied were derived from different clones given their heterogeneous nature. MLVA based on seven selected VNTR loci was rapid, reproducible and highly discriminative and therefore may complement PFGE for routine subtyping of S. sonnei. [ABSTRACT FROM AUTHOR]

Vibrio cholerae is an estuarine bacterium associated with a single peak of cholera (March-May) in coastal villages of Bangladesh. For an unknown reason, however, cholera occurs in a unique dual peak (March-May and September-November) pattern in the city of Dhaka that is bordered by a heavily polluted freshwater river system and flood embankment. In August 2007, extreme flooding was accompanied by an unusually severe diarrhea outbreak in Dhaka that resulted in a record high illness. This study was aimed to understand the unusual outbreak and if it was related to the circulation of a new V. cholerae clone. Nineteen V. cholerae isolated during the peak of the 2007 outbreak were subjected to extensive phenotypic and molecular analyses, including multi- locus genetic screening by polymerase chain reaction (PCR), sequence-typing of the ctxB gene, and pulsed-field gel electrophoresis (PFGE). Factors associated with the unusual incidence of cholera were determined and analysis of the disease severity was done. Overall, microbiological and molecular data confirmed that the hypervirulent V. cholerae was O1 biotype El Tor (ET) that possessed cholera toxin (CT) of the classical biotype. The PFGE (NotI) and dendrogram clustering confirmed that the strains were clonal and related to the pre-2007 variant ET from Dhaka and Matlab and resembled one of two distinct clones of the variant ET confirmed to be present in the estuarine ecosystem of Bangladesh. Results of the analyses of both diarrheal case data for three consecutive years (20062008) and regional hydroclimatology over three decades (19802009) clearly indicate that the pattern of cholera occurring in Dhaka, and not seen at other endemic sites, was associated with flood waters transmitting the infectious clone circulating via the fecal-oral route during and between the dual seasonal cholera peaks in Dhaka. Circular river systems and flood embankment likely facilitate transmission of infectious V. cholera throughout the year that leads to both sudden and off-season outbreaks in the densely populated urban ecosystem of Dhaka. Clonal recycling of hybrid ElT or with increasing virulence in a changing climate and in a region with a growing urban population represents a serious public health concern for Bangladesh. [ABSTRACT FROM AUTHOR]

Summary The genus Borrelia is arthropod-borne infectious agents in vertebrates, and is classified into Lyme disease (LD) Borrelia spp. and Relapsing fever (RF) Borrelia spp. In addition to these Borrelia groups, we recently reported reptile-associated (REP) Borrelia spp. from reptiles and from hard-bodied ticks, which probably transmitted the REP Borrelia spp. In this study, we investigated the presence of REP Borrelia sp. in moulted ticks, and found that trans-stadial transmission of REP Borrelia sp. occurred in the midgut, while it was observed that REP Borrelia sp. entered the salivary gland during blood-feeding. This characteristic is also found in LD Borrelia spp., which are also transmitted by hard-bodied ticks. Although phylogenetic analysis demonstrated that REP Borrelia spp. are similar to RF Borrelia spp., the ecology of the spirochaetes within the vector ticks is different for REP Borrelia spp. and RF Borrelia spp. Elucidation of the evolutionary history of the genus Borrelia and its adaptation to ticks promises to be of great interest to researchers of vector-borne microorganisms. [ABSTRACT FROM AUTHOR]

We previously reported that mutation of galE in Porphyromonas gingivalis has pleiotropic effects, including a truncated lipopolysaccharide (LPS) O-antigen and deglycosylation of the outer membrane protein OMP85 homolog. In the present study, further analysis of the galE mutant revealed that it produced little or no outer membrane vesicles (OMVs). Using three mouse antisera raised against whole cells of the P. gingivalis wild type strain, we performed ELISAs to examine the reactivity of these antisera with whole cells of the wild type or the galE mutant. All three antisera had significantly lower reactivity against the galE mutant compared to wild type. OMVs, but not LPS, retained the immunodominant determinant of P. gingivalis, as determined by ELISAs (with wild type LPS or OMVs as antigen) and absorption assays. In addition, we assessed the capacity of OMVs as a vaccine antigen by intranasal immunization to BALB/c mice. Synthetic double-stranded RNA polyriboinosinic polyribocytidylic acid [Poly (I:C)], an agonist of Toll-like receptor 3 (TLR3), was used as the mucosal adjuvant. Vaccination with OMV elicited dramatically high levels of P. gingivalis-specific IgA in nasal washes and saliva, as well as serum IgG and IgA. In conclusion, the OMVs of P. gingivalis have an important role in mucosal immunogenicity as well as in antigenicity. We propose that P. gingivalis OMV is an intriguing immunogen for development of a periodontal disease vaccine. [ABSTRACT FROM AUTHOR]

The expression of the type III secretion system-a main determinant of virulence in Shigella-is controlled by regulator cascades VirF-InvE (VirB) and CpxAR two-component system. A screen for mutants that restore virulence in the cpxA background led to the isolation of a mutant of rodZ, a cytoskeletal protein that maintains the rod-shaped morphology of bacilli. InvE is normally repressed at 30 °C because of decreased messenger RNA (mRNA) stability, but rodZ mutants markedly increase invE-mRNA stability. Importantly, the inhibition of InvE production by RodZ can be genetically separated from its role in cell-shape maintenance, indicating that these functions are distinguishable. Thus, we propose that RodZ is a new membrane-bound RNA-binding protein that provides a scaffold for post-transcriptional regulation. [ABSTRACT FROM AUTHOR]

mong clinically isolated β-hemolytic streptococci, Streptococcus pyogenes and S. agalactiae were considered the main pathogens in humans until recently. In 1996, S. dysgalactiae subsp. equisimilis (SDSE) was proposed as a novel taxon among human-derived streptococcal isolates. SDSE has Lancefield group C or G antigens, exhibits strong β-hemolysis, and exerts streptokinase activity upon human plasminogen and proteolytic activity upon human fibrin. Similarly to group A streptococci, SDSE possesses virulence factors including M protein, streptolysin O, streptolysin S, streptokinase, hyaluronidase, C5a peptidase, and others. SDSE may exist among the normal flora of the skin, oropharynx, and gastrointestinal and genitourinary tracts. In the twenty-first century, invasive SDSE infection (i.e., cellulitis, urosepsis, and pneumonia) leading to various disseminated diseases is being diagnosed increasingly in Japan, elsewhere in Asia, in Europe, and in America. Particularly, among elderly patients, these invasive diseases are encountered increasingly in Japanese hospital emergency departments. Analysis of the part of the emm gene encoding the amino acid sequence at the N-terminal end of the M protein is used to determine the molecular epidemiology of SDSE. The distribution of emm types from patients with invasive or noninvasive infections differs between surveillance results from different countries. In this review, we summarize the characteristics of phenotypes and virulence factors in SDSE strains; the review also focuses on emerging SDSE infectious disease and future vaccination research. [ABSTRACT FROM AUTHOR]

To describe clinical aspects of pandemic (H1N1) 2009 virus-associated pneumonia in children, we studied 80 such children, including 17 (21%)with complications, who were admitted to 5 hospitals in Japan during August-November 2009 after a mean of 2.9 symptomatic days. All enrolled patients recovered (median hospitalization 6 days). Timely access to hospitals may have contributed to favorable outcomes. [ABSTRACT FROM AUTHOR]

Two cases of ruptured aneurysms in the posterior cervical regions associated with type-1 neurofibromatosis treated by transcatheter embolization are reported. Patients presented with acute onset of swelling and pain in the affected areas. Emergently performed contrast-enhanced CT demonstrated aneurysms and large hematomas widespread in the posterior cervical regions. Angiography revealed aneurysms and extravasations of the occipital artery. Patients were successfully treated by percutaneous transcatheter arterial microcoil embolization. Transcatheter arterial embolization therapy was found to be an effective method for treating aneurysmal rupture in the posterior cervical regions occurring in association with type-1 neurofibromatosis. A literature review revealed that rupture of an occipital arterial aneurysm, in the setting of neurofibromatosis type 1, has not been reported previously. [ABSTRACT FROM AUTHOR]

ABSTRACT Enterohemorrhagic Escherichia coli (EHEC), a food- and waterborne pathogen, causes diarrhea, hemorrhagic colitis, and life-threatening HUS. MLVA is a newly developed and widely accepted genotyping tool. An MLVA system for EHEC O157 involving nine genomic loci has already been established. However, the present study revealed that the above-mentioned MLVA system cannot analyze EHEC O26 and O111 isolates-the second and third most dominant EHEC serogroups in Japan, respectively. Therefore, with several modifications to the O157 system and the use of nine additional loci, we developed an expanded MLVA system applicable to EHEC O26, O111, and O157. Our MLVA system had a relatively high resolution power for each of the three serogroups: Simpson's index of diversity was 0.991 (95% CI = 0.989-0.993), 0.988 (95% CI, 0.986-0.990), and 0.986 (95% CI, 0.979-0.993) for O26, O111, and O157, respectively. This system also detected outbreak-related isolates; the isolates collected during each of the 12 O26 and O111 outbreaks formed unique clusters, and most of the repeat copy numbers among the isolates collected during the same outbreak exhibited no or single-locus variations. These results were comparable to those of cluster analyses based on PFGE profiles. Therefore, our system can complement PFGE analysis-the current golden method. Because EHEC strains of three major serogroups can be rapidly analyzed on a single platform with our expanded MLVA system, this system could be widely used in molecular epidemiological studies of EHEC infections. [ABSTRACT FROM AUTHOR]

Objective: To preliminarily evaluate the feasibility and usefulness of MR elastography of the liver at 3 T with cine-tagging and bending energy (BE) analysis for the evaluation of hepatic fibrosis.Materials and Methods: Twenty-two patients underwent MR elastography with four different cine-tagging grids on the liver (16- or 20-mm sagittal or coronal). Nine images serially obtained during 1-s of exhalation were analyzed to define coordinates of grid intersections. BE values were calculated using the thin-plate spline method. BE values were compared among patient groups with different fibrosis stage thresholds.Results: In the 22 patients, six had a fibrosis score of F0, one had F1, seven had F2, three had F3, and five had F4. Mean BE value with 16-mm sagittal grid was greater with fibrosis score F0 (1.54 ± 0.63) than with ≥F1 (0.97 ± 0.12, P = 0.013) as well as with ≤F1 (1.48 ± 0.60) than with ≥F2 (0.96 ± 0.36, P = 0.019).Conclusion: Our results showed that MR elastography with 16-mm sagittal grid and BE analysis had a potential in discrimination for the patients with moderate or advanced hepatic fibrosis from those with healthy liver or slight fibrosis. [ABSTRACT FROM AUTHOR]

Purpose: To compare 11C-choline positron emission tomography (C-PET), 18F-fluorodeoxyglucose PET (FDG-PET), and MR imaging in the preoperative detection of prostate cancer. Materials and Methods: C-PET, FDG-PET, and MR images were obtained in 43 consecutive patients with suspected prostate cancer, and prostate cancers were histopathologically confirmed in 26 patients. Unenhanced T1-weighted, T2-weighted, and gadolinium-enhanced MR images were obtained. C-PET and FDG-PET were conducted 1.5 and 60 minutes after injection of 5.5 and 5.0 MBq/kg tracers, respectively. A nuclear and a genitourinary radiologist retrospectively reviewed PET and MR images at random, respectively, and assigned a confidence level for the presence of prostate cancer using a four-point scale. Diagnostic performance was tested using the McNemar test and receiver operating characteristic curve analysis. Results: The sensitivity was greater ( P < 0.05) with MR (88%) and C-PET (73%) images than with FDG-PET images (31%). The accuracy was greater ( P < 0.05) with MR images (88%) than with C-PET (67%) and FDG-PET (53%) images. The area-under-curve value with MR (0.90) was greater than those with C-PET (0.53) and FDG-PET (0.54) images ( P < 0.01). Conclusion: MR imaging should be primarily performed in the preoperative detection of prostate cancer. C-PET and FDG-PET did not improve the detection. J. Magn. Reson. Imaging 2010;31:1151-1156. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The members of the genus Borrelia are transmitted by arthropods and known to be infectious to vertebrates. Here we found isolates and DNAs belonging to the Borrelia turcica and unknown Borrelia species from imported reptiles and their ectoparasites. The Borrelia strains were isolated from blood and multiple organs of exotic tortoises, and were experimentally infectious to captive-bred tortoises. These findings suggest that these tortoises may be a candidate as the reservoir host of the Borrelia species. In this study, the Borrelia strains were also isolated from and/or detected in hard-bodied ticks, Amblyomma ticks and Hyalomma ticks. In some of these ticks, immunofluorescence imaging analysis revealed that the Borrelia had also invaded into the tick salivary glands. Accordingly, these ticks were expected to be a potential vector of the Borrelia species. Sequencing analyses of both housekeeping genes ( flaB gene, gyrB gene and 16S rDNA gene) and 23S rRNA gene-16S rRNA gene intergenic spacer region revealed that these Borrelia strains formed a monophyletic group that was independent from two other Borrelia groups, Lyme disease Borrelia and relapsing fever Borrelia. From these results, the novel group of Borrelia comprises the third major group of arthropod-transmitted borreliae identified to date. [ABSTRACT FROM AUTHOR]

Genes essential for eliciting pathogenicity of enterohemorrhagic Escherichia coli are located within the locus of enterocyte effacement (LEE). Expression of LEE genes is positively regulated by paralogues PchA, PchB and PchC, which are encoded by separate loci of the chromosome. To elucidate the underlying regulatory mechanism, we screened transposon mutants exhibiting reduced expression of pchA, transcription level of which is highest among the pch genes. Here, we report that the LysR-homologue A (LrhA) positively regulated the transcription of pchA and pchB. A deletion in lrhA reduced the transcription levels of pchA and pchB to different degrees, and also reduced the expression of LEE-coded type 3-secreted protein, EspB. Expression of LrhA from a plasmid restored and markedly increased the transcription levels of pchA and pchB respectively, and highly induced EspB expression. Deletion analysis of the regulatory region showed that both promoter-proximal (−195 to +88) and promoter-distal (−418 to −392 for pchA and −391 to −375 for pchB) sequences were required for the LrhA-mediated upregulation of pchA and pchB genes. Purified His6-LrhA protein differentially bound to the regulatory regions of pchA/B, suggesting that direct regulation of pchA and pchB genes by LrhA in turn controls the expression of LEE genes. [ABSTRACT FROM AUTHOR]

Objective: Measurement of salivary IgA antibody (PAc-peptide antibody, PPA) to amino acid residues 361–386 of Streptococcus mutans PAc, which possess a multiple binding motif to various HLA-DR molecules and a B-cell epitope that recognises the inhibiting antibody to S. mutans, is an indicator for the population numbers of mutans streptococci (MS) in human saliva. The purpose of this study was to clarify the role of PPA in infection control of MS after professional oral hygiene care. Materials and methods: Thirty-nine dependently living institutionalised elderly subjects (75.9 ± 7.5 years; 10 males, 29 females) participated in the study. The measurements of PPA, MS, total streptococci (TS) and lactobacilli (LB) were performed by ELISA and culture techniques from saliva, plaque and tongue samples from the elderly. Results: After treatment using professional oral care, the numbers of MS decreased significantly at 6 months in saliva and tongue samples from the group not having PPA in comparison with the primary data; whereas in the PPA-detected group, a significant decrease in MS number was shown immediately following professional care at 1–12 months in all samples. There was little difference in the numbers of LB at any of the time points. The numbers of TS decreased rapidly in PPA-not detected group in comparison with the PPA-detected group. Conclusion: PPA may be more effective for controlling MS number in the oral cavity after professional treatment. The measurement of PPA may be used for preventive instruction to dental caries at the chair side in the clinical setting. [ABSTRACT FROM AUTHOR]

We developed a specific and rapid detection system for Rickettsia japonica and R. heilongjiangensis, the causative agents of spotted fever, using a TaqMan minor groove binder probe for a particular open reading frame (ORF) identified by the R. japonica genome project. The target ORF was present only in R. japonica-related strains. [ABSTRACT FROM AUTHOR]

We determined the genotype of cholera toxin by amplifying and sequencing the B-subunit in a sequential collection of 90 strains of Vibrio cholerae O139 isolated over the past 13 years since its first description in 1992. Representative strains isolated during 1993–1997 harboured ctxB of El Tor type (genotype 3). Twenty-six strains isolated during 1999, 2001, 2005 and three strains isolated in 1998, 2000 and 2002 were identified to belong to new ctxB genotypes 4 and 5, respectively. Genotype 5 was similar to genotype 1 except at position 28 (D→A). The genotype 6 was similar to genotype 4 except at position 34 (H→P). The implication of switch in terms of function of the toxin and its impact on human disease is unclear. How this change has influenced their prevalence relative to that of V. cholerae O1 in human infection is also not clear. The other common virulence gene clusters including the Vibrio pathogenicity island-1, Vibrio seventh pandemic island (VSP)-I and VSP-II of V. cholerae O139 did not show any remarkable difference from that of the O1 El Tor strains. Overall, the majority of the O139 strains tested in this study were similar to the El Tor strains but had altered ctxB genotype. This change and the impact that it causes to the epidemiology of cholera caused by O139 should be closely monitored. [ABSTRACT FROM AUTHOR]

Peripheral blood from a ball python (Python reginus) imported from Ghana was cultured in Barbour-Stoenner-Kelly (BSK) medium for Borrelia spp. isolation, resulting in the prominent appearance of free, and clusters of, trypanosomes in a variety of morphological forms. The molecular phylogenetic characterization of these cultured trypanosomes, using the small subunit rDNA, indicated that this python was infected with a species closely related to Trypanosoma varani Wenyon, 1908, originally described in the Nile monitor lizard (Varanus niloticus) from Sudan. Furthermore, nucleotide sequences of glycosomal glyceraldehyde- 3-phosphate dehydrogenase gene of both isolates showed few differences. Giemsa-stained blood smears, prepared from the infected python 8 mo after the initial observation of trypanosomes in hemoculture, contained trypomastigotes with a broad body and a short, free flagellum; these most closely resembled the original description of T. varani, or T. voltariae Macfie, 1919 recorded in a black-necked spitting cobra (Naja nigricollis) from Ghana. It is highly possible that lizards and snakes could naturally share an identical trypanosome species. Alternatively, lizards and snakes in the same region might have closely related, but distinct, Trypanosoma species as a result of sympatric speciation. From multiple viewpoints, including molecular phylogenetic analyses, reappraisal of trypanosome species from a wide range of reptiles in Africa is needed to clarify the relationship of recorded species, or to unmask unrecorded species. [ABSTRACT FROM AUTHOR]

A recombinant positive control plasmid was developed to be used in PCR for Orientia tsutsugamushi. This pUC19-based plasmid contains the O. tsutsugamushi DNA sequence, part of which is replaced with Candida albicans DNA. pUC19-Posi is a PCR control that provides several advantages over currently used positive controls for both universal and serotypical PCR. [ABSTRACT FROM AUTHOR]

Ehrlichia-specific DNA fragments of Ehrlichia omp-1 and groEL genes were found in two I. granulatus ticks which had been collected from wild small mammals in a subtropical zone in Japan. The DNA sequences of groEL and 16SrDNA of the suspected Ehrlichia were clustered into a group of E. chaffeensis, E. muris, and Ehrlichia sp. HF565 found in I. ovatus, but were distinctly different. Therefore the Ehrlichia strain was designated as a novel Ehrlichia sp. 360. The Ehrlichia sp. 360 was detected in I. granulatus but not in any other ticks. This suggests that I. granulatus is a probable vector of Ehrlichia sp. 360 in Japan. [ABSTRACT FROM AUTHOR]

Background: The expression of Type III secretion system (TTSS) in Shigella is regulated in response to changes in environmental osmolarity and temperature. Temperature-dependent regulation of virF, the master regulator of TTSS synthesis, is believed to occur at the transcriptional level. We recently demonstrated, however, that TTSS synthesis also involves post-transcriptional regulation of the synthesis of InvE, a target of virF and key regulator of TTSS synthesis. The mRNA levels of invE (virB) are stable at 37°C, but mRNA stability markedly decreases at low temperatures where the TTSS synthesis is tightly repressed. Deletion of hfq, which encodes an RNA chaperone in Gram-negative bacteria, results in the restoration of expression of invE and other TTSS genes at low temperature due to an increase in the stability of invE mRNA. To date, the molecular details of the regulation of TTSS expression in response to osmotic pressure are not known. In the current study, we investigated the mechanism of regulation of TTSS by osmotic pressure. Results: Transcription of virF, which encodes the master regulator of TTSS expression, was partially repressed under low osmotic conditions. Several lines of evidence indicated that osmolarity-dependent changes in TTSS synthesis are controlled at the post-transcriptional level, through the regulation of InvE synthesis. First, the expression InvE protein was tightly repressed under low osmotic growth conditions, even though invE mRNA transcripts were readily detectable. Second, under low osmotic conditions, invE mRNA was rapidly degraded, whereas deletion of hfq, which encodes an RNA chaperone, resulted in increased invE mRNA stability and the production of InvE protein. Third, the binding of purified Hfq in vitro to invE RNA was stronger in low-salt buffer, as assessed by gel-shift analysis and surface plasmon resonance (Biacore analysis). Conclusion: Osmolarity-dependent changes in TTSS synthesis in Shigella involve the post-transcriptional regulation of InvE expression, in addition to partial transcriptional activation by virF. The stability of invE mRNA is reduced under low osmotic conditions, similar to the effect of temperature. Deletion of an RNA chaperone gene (hfq) abolished the repression of TTSS synthesis at low osmolarity through a mechanism that involved increased stability of invE mRNA. We propose that the expression of Shigella virulence genes in response to both osmolarity and temperature involves the post-transcriptional regulation of expression of InvE, a critical regulator of TTSS synthesis. [ABSTRACT FROM AUTHOR]