Emerging ST121/agr4 community-associated methicillin-resistant Staphylococcus aureus (MRSA) with strong adhesin and cytolytic activities: trigger for MRSA pneumonia and fatal aspiration pneumonia in an influenza-infected elderly.

The pathogenesis of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) pneumonia in influenza-infected elderly individuals has not yet been elucidated in detail. In the present study, a 92-year-old man infected with influenza developed CA-MRSA pneumonia. His CA-MRSA was an emerging type, originated in ST121/agr4 S. aureus, with diversities of Panton-Valentine leucocidin (PVL)(-)/spat5110/SCCmecV(+) versus PVL(+)/spat159((etc.))/SCCmec (-), but with common virulence potentials of strong adhesin and cytolytic activities. Resistance to erythromycin/clindamycin (inducible-type) and gentamicin was detected. Pneumonia improved with the administration of levofloxacin, but with the subsequent development of fatal aspiration pneumonia. Hence, characteristic CA-MRSA with strong adhesin and cytolytic activities triggered influenza-related sequential complications.

Atomic-scale heterogeneity of a multicomponent bulk metallic glass with excellent glass forming ability.

We report the atomic structure of a multicomponent Cu45Zr45Ag10 bulk metallic glass investigated by state-of-the-art experimental and computational techniques. In comparison with a binary Cu50Zr50 metallic glass, Zr-rich interpenetrating clusters centered by paired and stringed Ag atoms and Cu-rich icosahedra are widely observed in the ternary Cu45Zr45Ag10 alloy. The atomic-scale heterogeneity caused by chemical short- and medium-range order is found to play a key role in stabilizing the liquid phase and in improving the glass forming ability of the multicomponent alloy.

Color development of squid skin as affected by oxygen concentrations.

Color development of squid skin was controlled by O2 concentration for storage. When stored above 10% O2, the color index (CI) as an index of color development of skin increased in 24 h, and decreased gradually with further storage. The CI profile at 10% O2 was practically identical to that in air. When stored at 0.1% O2, in the presence of N2, the CI increased partly in 6 h and decreased. Morphological observation of chromatophore distinguished the CI increase at 0.1% and 10% O2 by their shape and size distribution. However, the storage of squid at O2 concentration between 2.5% and 7% practically did not change the CI for at least 48 h. ATP content of skin was kept unchanged when the storage atmosphere contained O2 concentration at 2.5% up to 48 h, while the content decreased rapidly with a half decrease in 6 h when stored at 0.1% O2. It was demonstrated clearly that ATP is regenerated in the presence of O2, but the ATP concentration did not determine the CI change during the storage. Exposure to high concentration of O2 might induce a full color development of squid skin.

Identification of bradykinin: related peptides from Phyllomedusa nordestina skin secretion using electrospray ionization tandem mass spectrometry after a single-step liquid chromatography

Amphibian skin secretions are a source of potential new drugs with medical and biotechnological applications. Rich in peptides produced by holocrine-type serous glands in the integument, these secretions play different roles, either in the regulation of physiological skin functions or in the defense against predators or microorganisms. The aim of the present work was to identify novel peptides with bradykinin-like structure and/or activity present in the skin of Phyllomedusa nordestina. In order to achieve this goal, the crude skin secretion of this frog was pre-fractionated by solid phase extraction and separated by reversed-phase chromatography. The fractions were screened for low-molecular-mass peptides and sequenced by mass spectrometry. It was possible to identify three novel bradykinin-related peptides, namely: KPLWRL-NH2 (Pnor 3), RPLSWLPK (Pnor 5) and VPPKGVSM (Pnor 7) presenting vascular activities as assessed by intravital microscopy. Pnor 3 and Pnor 7 were able to induce vasodilation. On the other hand, Pnor 5 was a potent vasoconstrictor. These effects were reproduced by their synthetic analogues.

Transglutaminase differentially regulates growth signalling in rat perivenous and periportal hepatocytes.

The influence of transglutaminase 2 (TG2) activity on the proliferative effect of epidermal growth factor (EGF) and on EGF receptor affinity in periportal hepatocytes (PPH) and perivenous hepatocytes (PVH) has been investigated using a primary culture system. PPH and PVH subpopulations have been isolated using the digitonin/collagenase perfusion technique. DNA synthesis was assessed by [3H] thymidine incorporation into hepatocytes. The assay for binding of [125I] EGF to cultured hepatocytes was analysed by Scatchard plot analysis. Pretreatment with the TG2 inhibitor monodansylcadaverine (MDC) greatly increased EGF-induced DNA synthesis in both PPH and PVH. Furthermore, [125I] EGF binding studies in PVH treated with MDC indicated that high-affinity EGF receptor expression was markedly up-regulated, whereas in PPH, there was no significant effect. Treatment with retinoic acid (RA), an inducer of TG2 expression, significantly decreased EGF-induced DNA synthesis in both PPH and PVH. Binding studies in the presence of RA revealed that the high-affinity EGF receptor was down-regulated and completely absent in both PPH and PVH. These results suggest that TG2 was involved in the differential growth capacities of PPH and PVH through down-regulation of high-affinity EGF receptors.

Conformation and lytic activity of eumenine mastoparan: a new antimicrobial peptide from wasp venom.

Eumenine mastoparan-AF (EMP-AF) is a novel membrane active tetradecapeptide recently isolated from the venom of solitary wasp, Anterhynchium flavomarginatum micado. It was reported previously that EMP-AF peptide presented low cytolytic activities in human erythrocytes and in RBL-2H3 mast cells. In the present work, we observed that this peptide is able to permeate anionic liposomes, and in less extension also the neutral ones. We present evidences showing that the permeation ability is well correlated with the amount of helical conformation assumed by the peptides in these environments. This peptide also showed a broad-spectrum inhibitory activity against Gram-positive and Gram-negative bacteria. The permeability of liposomes and the antibiotic effect showed a significant reduction when C-terminus was deamidated (in acidic form). The removal of the three first amino acid residues from the N-terminus rendered the peptide inactive both in liposomes and in bacteria. The results suggest that the mechanism of action involves a threshold in the accumulation of the peptide at level of cell membrane.

Differentiation of exudate from transudate ascites by Doppler sonography.

BACKGROUND: We investigated whether the addition of Doppler sonography (US) increases the diagnostic confidence of US for estimating the nature of ascites. METHODS: Of the 127 cases reviewed in this study, there were 42 cases of transudate and 85 of exudate ascites. We reviewed the US, power Doppler, and pulsed Doppler images of these cases. RESULTS: With US, the transudate ascites was imaged as free of echo in 38 of 42 cases (90.5%). The exudate ascites was imaged as free of echo in 22 of 85 cases (25.9%) and with internal echo spots in 63 of 85 cases (74.1%). With Doppler US, we obtained distinct pulsed signals from the transudate ascites in only two of 36 cases (5.6%). In contrast, we obtained distinct Doppler signals from the exudate ascites in 66 of 79 cases (83.5%). Those 66 cases included 16 of the 22 cases with echo-free ascites. CONCLUSION: The presence or absence of echo spots within the ascites helped differentiate transudate from exudate ascites, as reported in the literature. However, the addition of Doppler US contributed to the differentiation of echo-free exudate (Doppler signals present) from echo-free transudate (Doppler signals absent) ascites.

Appendiceal mucocele: sonographic findings.

BACKGROUND: Appendiceal mucocele (AM) is a relatively rare disease, and its sonograms (US) have not been sufficiently analyzed. METHODS: We studied the US findings of five patients with AM, with special attention to AM size, shape, internal echoes, and the mode of back echoes. RESULTS: All five cases showed an elongated mass in the lower right abdomen. Internal echoes were present in all cases and M-mode US confirmed the movement of those echoes. The echogenecity of the lesion changed according to the frequency of the transducer used. Only one case showed posterior echo enhancement, and no case showed lateral shadowing. CONCLUSION: AM appears as an elongated echo-poor mass without posterior echo enhancement. The cyst wall is less distinct than what one would expect for a cyst. When encountering such a mass in the lower right abdomen, one should strongly suspect an AM. In such cases, appropriate diagnostic and therapeutic strategies are especially necessary to prevent rupture that results in development of pseudomyxoma peritonei.

Dilatation of the cystic duct in patients with obstructive jaundice.

BACKGROUND: It is well known that obstructive jaundice causes biliary dilatation, but sonographic (US) findings of the cystic duct in patients with obstructive jaundice are rarely reported. METHODS: We reviewed US findings in 25 such patients. RESULTS: US findings of dilated cystic duct could be divided roughly into two patterns: tortuous and tubular. The former pattern was a tortuously dilated cystic duct arising from the gallbladder neck, running predominantly deeply, turning anteromedially, and then joining the posterior face of the common hepatic duct. The latter pattern was a straight dilated cystic duct running parallel with the common hepatic duct, giving the appearance of a septated bile duct. CONCLUSION: A better understanding of the US findings of dilated cystic duct translates into improved biliary US diagnosis.

A severe hepatic disorder with myelodysplastic syndrome, treated with cytarabine ocfosfate, in a dog.

An 8-year-old female Shih Tzu was presented with weight loss and vomiting. Alanine aminotransferase was high and abdominal radiographs revealed hepato- and splenomegaly. Mild anaemia, neutrophilia with left shift, eosinophilia, a thrombocytosis with dysplastic features of eosinophils and platelets, were detected. The animal was initially considered to have hepatitis and was treated accordingly, but clinical signs persisted. Histological examination of liver biopsy samples showed disruption of the hepatic lobule, with extensive infiltration by haemopoietic cells. Further investigation of the bone marrow suggested a diagnosis of myelodysplastic syndrome. The animal was treated with cytarabine ocfosfate, a prodrug of cytosine arabinoside, and appeared to recover.

Retroperitoneal cyst: sonographic findings.

BACKGROUND: Retroperitoneal cyst (RC) is a relatively rare disease, and its sonographic (US) findings have not been analyzed sufficiently. METHODS: We studied US findings of five patients with RC, with special attention to location, size, shape, internal echoes, the presence or absence of lateral shadowing, and the mode of back echoes. RESULTS: In all cases, the cyst was situated behind (four cases) or lateral to (one case) the pancreas: behind or lateral to the pancreatic head in two cases, behind the pancreatic body in one case, and behind the pancreatic tail in two cases. Four cases showed a round mass (three cases) or multiple round mass (one case). Internal echoes were present in those cases and showed a "pseudo-solid" pattern. In those cases, M-mode US confirmed the movement of those internal echoes. In the remaining case, the lesion was imaged as an irregularly shaped multilocular mass. No case showed posterior echo enhancement, and no case showed lateral shadowing. No blood flow signals from the lesion were seen. CONCLUSION: Unlike ordinary cysts, RC usually is imaged as a round mass behind the pancreas, with dense internal echoes without lateral shadowing or posterior echo enhancement, which presents a "pseudo-solid" pattern. A diagnosis of RC should be considered when encountering a mass with such US findings.

Potential remedy against Echinococcus multilocularis in wild red foxes using baits with anthelmintic distributed around fox breeding dens in Hokkaido, Japan.

The effect of bait-delivered anthelmintic to reduce the prevalence of Echinococcus multilocularis in wild red foxes was evaluated in Koshimizu, in the eastern part of Hokkaido, Japan. The study area (200 km2) was divided into baited and non-baited sections. The anthelmintic baits were distributed around fox den sites in the baited section every month for 13 months. After 1 year of the anthelmintic bait distribution, the prevalence of E. multilocularis in foxes, evaluated either by the parasite egg examination (from 27.1 to 5.6%) or coproantigen ELISA (from 59.6 to 29.7%), decreased in the baited section contrasting to that in the non-baited section (parasite egg: from 18.8 to 24.2%; ELISA: from 41.9 to 45.8%). The prevalence of E. multilocularis in grey red-backed vole Clethrionomys rufocanus, caught around fox dens, born after bait distribution also decreased and was significantly lower than that in non-baited section. However, within the study periods, the coproantigen-positive rate in fox faeces sporadically increased, while egg-positive rate constantly decreased. Since coproantigen ELISA can detect pre-patent infection, this observation indicates that reinfection pressure in the baited section was still high even after the 13 months of anthelmintic bait distribution. Therefore, the bait distribution longer than our study period is required for the efficient control of E. multilocularis in wild red fox population.

Accessory hepatic duct: sonographic findings.

Accessory hepatic ducts are relatively rare biliary anomalies. They have been reported only sporadically, and very few reports have described their sonographic (US) findings. Our experience with two such cases suggested that a diagnosis of an accessory hepatic duct should be considered when US shows a fine tubular structure or an anechoic or hypoechoic oval mass with acoustic shadowing at the level between the hepatic hilus and the common bile duct. A good knowledge of the US findings will determine the diagnostic and therapeutic strategies.

Primary carcinoid tumor of the liver: report of two cases with an emphasis on US findings.

Primary carcinoid tumor of the liver is rare, and its sonographic (US) findings have rarely been reported. We present two histologically proven cases. Both patients were asymptomatic and huge masses, found incidentally by US, were echogenic with many cystic areas. Lesions were markedly hypervascular on color Doppler US and angiography. Thus, primary carcinoid tumor of the liver should be considered when US detects this type of mass in asymptomatic patients.

Abdominal lymphoma: differentiation from pancreatic carcinoma with Doppler US.

BACKGROUND: Marked lymphadenopathy around the pancreas due to lymphoma (abdominal lymphoma) occasionally can mimic a total pancreatic carcinoma on ultrasonography (US). We investigated whether US and color Doppler US allowed differentiation between those pathologies. METHODS: We analyzed the US and color Doppler results of 12 cases of abdominal peripancreatic lymphoma and 21 cases of total pancreatic carcinoma. RESULTS: With regard to shape, echogenicity of the lesion, and mode of vascular involvement, there was no difference between groups. With regard to maximal velocities and resistive indices of the involved vessels, there was no difference between groups. However, the presence of turbulent flows in the involved vessels was seen exclusively in the pancreatic carcinoma group. CONCLUSION: The presence or absence of turbulent flow in the involved vessels is a very important finding for differentiating abdominal lymphomas from total pancreatic carcinomas.

Mesenteric lipoma: report of a case with emphasis on US findings.

Mesenteric lipoma (ML) is a relatively rare disease that has been very infrequently reported. We present the clinical data and medical imaging results of an asymptomatic case with ML incidentally detected by sonography (US). On US the lesion was imaged as a well-demarcated hypoechoic mass with multiple linear echoes. The mass also changed location under probe compression. The lesion was imaged as a clearly demarcated non-enhanced homogeneous fat-density mass on CT. Color Doppler US and angiography confirmed the avascular nature of the mass. Knowledge of the US findings in this case is useful for the diagnosis of ML.

Pharmacokinetics of a benzodithiin (RD3-0028) following aerosol treatment in rat.

1. RD3-0028, a benzodithiin compound, has potent antiviral activity against respiratory syncytial virus (RSV) in cell culture. The compound also inhibits growth of RSV and improves pathologic changes of interstitial pneumonia in the immunosuppressed mouse when delivered by small-particle aerosol. 2. In the present study, the absorption, distribution and excretion of 14C-RD3-0028 were compared in rat following either a single aerosol treatment or oral administration. 3. The plasma concentration was maintained at the same level from 5 min to 1 h, and decreased with a half-life of 2.2 +/- 0.1 h for 1-8 h. 4. The excretion of radioactivity in the urine and faeces at 24 h after aerosol treatment was 89.3 and 4.5%, respectively, indicating that almost all the radioactivity was rapidly excreted in the urine. The excretion of total radioactivity was 98.9% within 168 h. 5. The concentrations of radioactivity in the lung and trachea following aerosol treatment were higher than those in other tissues, and were detected even at 72 h. 6. These results suggest that the aerosol treatment might be useful for delivering RD3-0028 to the respiratory tract of RSV-infected patients.

Emphysematous cholecystitis: sonographic findings.

BACKGROUND: Emphysematous cholecystitis (EC) is a rare but life-threatening complication of acute cholecystitis, and an early diagnosis is required to prevent delay in patient management. Because sonography (US) is the first choice for diagnosing gallbladder diseases, US findings of EC should be understood more precisely. METHODS: We reviewed US findings of 11 surgically proven cases of EC (with small amounts of gas in three cases and large amounts in eight cases) and compared those with patients' clinical data. RESULTS: (1) In cases with small amounts of gas, US showed an echogenic line with a distinct ring-down artifact or a "powder snow-like" speckled posterior echo. (2) In cases with large amounts of gas, US showed a wide spiculated echogenic band with a powder snow-like speckled posterior echo or a speckled acoustic shadowing. In all cases, the presence of gas prevented visualization of the gallbladder wall. (3) US did not differentiate gas localized to the gallbladder wall and gas extending to the surrounding hepatic tissue. (4) Two diabetic cases showed gas throughout the intrahepatic bile ducts. In those cases, the time from diagnosis to recovery was relatively long. CONCLUSION: Our series showed some characteristic US patterns of EC. A good understanding of its US findings and appropriate emergent management will reduce the serious morbidity and mortality rates caused by EC.

Segmental chronic cholecystitis: sonographic findings and clinical manifestations.

BACKGROUND: In chronic cholecystitis, the gallbladder (GB) wall is usually evenly involved, whereas marked segmental thickening of the GB wall (segmental cholecystitis) seldom is reported. We wanted to define its clinical manifestations and sonographic (US) findings. METHODS: We reviewed the clinical and US data of 13 cases and compared these results with those of 30 patients with chronic cholecystitis with evenly thickened GB walls (usual-cholecystitis group). RESULTS: (a) All cases of segmental cholecystitis showed the portion distal to the kinking to be markedly thickened. (b) The thickened portion corresponded to the fundus in three cases, the body and fundus in seven cases, and the fundus, body, and infundibulum in three cases; and the thickened distal portion contained many stones in 11 cases. (c) There was no difference in the maximal diameters of the GB walls between the segmental-cholecystitis group and the usual-cholecystitis group. However, there was a significant difference in the minimal diameters of the GB walls between groups. CONCLUSION: Knowledge of the US findings and clinical presentations of segmental cholecystitis can help in the development of appropriate diagnostic and therapeutic strategies.