Cartilage T1ρ and T2 relaxation times: longitudinal reproducibility and variations using different coils, MR systems and sites.

OBJECTIVE: To evaluate the longitudinal reproducibility and variations of cartilage T1ρ and T2 measurements using different coils, MR systems and sites. METHODS: Single-Site study: Phantom data were collected monthly for up to 29 months on four GE 3T MR systems. Data from phantoms and human subjects were collected on two MR systems using the same model of coil; and were collected on one MR system using two models of coils. Multi-site study: Three participating sites used the same model of MR systems and coils, and identical imaging protocols. Phantom data were collected monthly. Human subjects were scanned and rescanned on the same day at each site. Two traveling human subjects were scanned at all three sites. RESULTS: Single-Site Study: The phantom longitudinal RMS-CVs ranged from 1.8% to 2.7% for T1ρ and 1.8-2.8% for T2. Significant differences were found in T1ρ and T2 values using different MR systems and coils. Multi-Site Study: The phantom longitudinal RMS-CVs ranged from 1.3% to 2.6% for T1ρ and 1.2-2.7% for T2. Across three sites (n = 16), the in vivo scan-rescan RMS-CV was 3.1% and 4.0% for T1ρ and T2, respectively. Phantom T1ρ and T2 values were significantly different between three sites but highly correlated (R > 0.99). No significant difference was found in T1ρ and T2 values of traveling controls, with cross-site RMS-CV as 4.9% and 4.4% for T1ρ and T2, respectively. CONCLUSION: With careful quality control and cross-calibration, quantitative MRI can be readily applied in multi-site studies and clinical trials for evaluating cartilage degeneration.

Osteoporotic changes of subchondral trabecular bone in osteoarthritis of the knee: a 3-T MRI study.

SUMMARY: Subchondral trabecular bone structure was analyzed in knee osteoarthritis (OA) patients using 3-T MRI to investigate structural features of subchondral trabecular bone of knee OA. With OA progression, osteoporotic changes were observed in the lateral joint, showing a higher correlation than sclerotic changes in the medial joint. INTRODUCTION: To investigate structural features of subchondral trabecular bone of knee osteoarthritis (OA). METHODS: Sixty knees with KL grade 0-4 (all female) were examined. Fast imaging employing steady-state acquisition-cycled phases (FIESTA-c) and FatSat Spoiled gradient recalled acquisition in the steady state (SPGR) images were acquired by 3-T MRI. At four sites (the medial femur, medial tibia, lateral femur, and lateral tibia), subchondral trabecular bone structure was analyzed by FIESTA-c imaging, cartilage area was measured by SPGR imaging, and their correlation was analyzed. In addition, the subjects were classified into four groups from the cartilage area measured by SPGR imaging, and subchondral trabecular bone structure in each group was compared. RESULTS: As cartilage area decreased in the medial joint, bone volume fraction and trabecular thickness in the medial tibia increased, and bone volume fraction, trabecular thickness, number, and connectivity in the lateral femur and lateral tibia decreased (r ≥ 0.4 or ≤-0.4, p ≤ 0.001). Compared to medially, the changes laterally showed a higher correlation. When the medial-lateral ratio of trabecular thickness in the tibia was determined, it had the highest correlation coefficient (r=-0.7, p < 0.001). These changes were not significantly detected in the early stage. CONCLUSIONS: To more sensitively detect OA changes in subchondral trabecular bone structure, a focus on osteoporotic changes in the lateral joint and the medial-lateral ratio would be useful. Detectability of early OA remains unknown, but based on a strong correlation with the degree of OA progression, trabecular structural analysis of subchondral bone may be a useful parameter to evaluate OA severity and evaluate treatment.

Elevated umbilical cord serum TARC/CCL17 levels predict the development of atopic dermatitis in infancy.

BACKGROUND: Thymus-and-activation-regulated chemokine (TARC; CCL17) is related to both allergy and pregnancy, but the relationships of maternal and umbilical cord blood CCL17 to atopic dermatitis (AD) development have not yet been examined. Objective Seventy paired full-term and normal vaginal delivery newborns and their mothers were enrolled in this study. METHODS: To elucidate the pathogenesis and fetomaternal inheritance of AD in infancy, CCL17, IFN-γ-inducible protein 10 kDa (IP-10; CXCL10), soluble HLA-G (sHLA-G), IgE and eosinophil counts were examined using sera from 70 paired umbilical cord and maternal blood samples. RESULTS: Serum CCL17 (r(s) =0.340, P<0.001) and sHLA-G (r(s) =0.600, P<0.001) levels showed high correlations between umbilical cord and maternal blood. Umbilical cord serum levels of CCL17 from neonates destined to develop AD in infancy were higher than in those from neonates who showed no signs of AD during infancy (median 1586.9 vs. 819.6 pg/mL, P<0.001). Serum levels of CCL17 were higher in mothers with AD than in those without AD (median 909.6 vs. 214.1 pg/mL, P<0.001). High umbilical cord serum levels of CCL17 were associated with infantile AD development even in 62 neonates born to mothers without AD (median 1514.4 vs. 740.6 pg/mL, P<0.001) and 38 neonates born to mothers with no allergies (median 1624.2 vs. 740.6 pg/mL, P<0.001). The summary estimates for umbilical cord serum CCL17 in the diagnosis of infantile AD were: sensitivity 85.7% (95% confidence interval: 72.8-98.7), specificity 73.8% (60.5-87.1), positive predictive value 68.6% (53.2-84.0) and negative predictive value 88.6% (78.0-99.1). CONCLUSION AND CLINICAL RELEVANCE: These findings suggest that the umbilical cord blood CCL17 may be involved in the pathogenesis of infantile AD and in fetomaternal inheritance. Serum levels of CCL17 from umbilical cord blood may be a predictive marker for AD in infancy.

Two cases of variceal haemorrhage during living-donor liver transplantation.

Some patients with cirrhosis experience rupture of venous varices before operation, and liver transplantation is a therapy of last resort for these patients. However, we have experienced two cases of intraoperative rupture in whom no abnormalities of the venous varices were seen on endoscopy before operation. One patient with ruptured gastrointestinal varices was treated by direct surgical ligation and the other with ruptured oesophageal gastric varices, spontaneously recovered with a Sengstaken-Blakemore tube. These cases suggest that acute variceal haemorrhage should always be considered as a possibility during living-donor liver transplantation in patients with a history of upper gastrointestinal bleeding. Careful observation of the nasogastic tube is important during clamping of the hepatic portal vein.

Novel factor highly conserved among eukaryotes controls sexual development in fission yeast.

In the fission yeast Schizosaccharomyces pombe, the onset of sexual development is controlled mainly by two external signals, nutrient starvation and mating pheromone availability. We have isolated a novel gene named rcd1+ as a key factor required for nitrogen starvation-induced sexual development. rcd1+ encodes a 283-amino-acid protein with no particular motifs. However, genes highly homologous to rcd1+ (encoding amino acids with >70% identity) are present at least in budding yeasts, plants, nematodes, and humans. Cells with rcd1+ deleted are sterile if sexual development is induced by nitrogen starvation but fertile if it is induced by glucose starvation. This results largely from a defect in nitrogen starvation-invoked induction of ste11+, a key transcriptional factor gene required for the onset of sexual development. The striking conservation of the gene throughout eukaryotes may suggest the presence of an evolutionarily conserved differentiation controlling system.

Mouse ULK2, a novel member of the UNC-51-like protein kinases: unique features of functional domains.

The UNC-51 serine/threonine kinase of C. elegans plays an essential role in axonal elongation, and unc-51 mutants exhibit uncoordinated movements. We have previously identified mouse and human cDNAs encoding UNC-51-like kinase (ULK1). Here we report the identification and characterization of the second murine member of this kinase family, ULK2. Mouse ULK2 cDNA encodes a putative polypeptide of 1033 aa which has an overall 52% and 33% amino acid identity to ULK1 and UNC-51, respectively. ULKs and UNC-51 share a typical domain structure of an amino-terminal kinase domain, a central proline/serine rich (PS) domain, and a carboxy-terminal (C) domain. Northern blot analysis showed that ULK2 mRNA is widely expressed in adult tissues. In situ hybridization analysis indicated that ULK2 mRNA is ubiquitously localized in premature as well as mature neurons in developing nervous system. ULK2 gene was mapped to mouse chromosome 11B1.3 and rat chromosome 10q23 by FISH. HA-tagged ULK2 expressed in COS7 cells had an apparent molecular size of approximately 150 kDa and was autophosphorylated in vitro. Truncation mutants suggested that the autophosphorylation occurs in the PS domain. Although expression of ULK2 failed to rescue unc-51 mutant of C. elegans, a series of ULK2/UNC-51 chimeric kinases revealed that function of the kinase and PS domains are conserved among species, while the C domain acts in a species-specific manner. These results suggest that ULK2 is involved in a previously uncharacterized signaling pathway in mammalian cells.

Characteristics of the melibiose transporter and its primary structure in Enterobacter aerogenes.

Cells of Enterobacter aerogenes can grow on melibiose as a sole source of carbon. This suggests the presence of melibiose operon in this organism. We found that E. aerogenes cells possess both alpha-galactosidase activity and melibiose transport activity, which were induced by melibiose. Neither Na+ nor Li+ stimulated the melibiose transport. However, transport of methyl-beta-thiogalactoside (TMG) was stimulated by Li+ but not by Na+. These findings suggest that the major coupling cation for the melibiose transporter in E. aerogenes is H+. In fact, we observed H+ entry into cells caused by an influx of melibiose and some of its analogs. We cloned the melB gene which encodes the melibiose transporter, and sequenced it. Deduced amino acid sequence of the transporter revealed that the melibiose transporter consists of 471 amino acid residues and the molecular weight was calculated to be 52214 Da. The sequence showed high homology with the sequences of the melibiose transporters of Escherichia coli, Salmonella typhimurium and Klebsiella pneumoniae. Higher homology was found with the melibiose transporter of K. pneumoniae than with that of E. coli and S. typhimurium.

Sequence of a melibiose transporter gene of Enterobacter cloacae.

We cloned a fragment of the chromosomal DNA of Enterobacter cloacae, which enabled a melibiose-negative Escherichia coli mutant lacking melB to grow on melibiose as the sole source of carbon. Transformed cells harboring the hybrid plasmid carrying the cloned DNA showed melibiose transport activity. The nucleotide sequence of the DNA region was determined. One complete open reading frame (ORF) and a part of another ORF were found in the region, and the amino acid sequences were deduced. The complete ORF was found to encode a melibiose transporter which consisted of 425 amino acid residues. Hydropathy analysis revealed that there are about 12 hydrophobic domains in this transporter. The incomplete ORF which exists in the upstream region of the transporter gene seemed to encode an alpha-galactosidase.

Cloning and nucleotide sequencing of phenylalanine dehydrogenase gene of Bacillus sphaericus.

The gene coding for phenylalanine dehydrogenase [PDH; L-phenylalanine: NAD+ oxidoreductase (deaminating); EC 1.4.1.-] from Bacillus sphaericus SCRC-79a was cloned onto plasmid pUC9, and the nucleotide sequence of the 2-kb DNA region of the insert was determined. A 1143-bp open reading frame consisting of 381 codons was identified as a pdh gene coding for PDH.

A rapid anticancer drug screening assay by [14C] thymidine uptake in cultured human cancer cells.

A rapid screening test by suppression of DNA synthesis in cancer cells was developed with [methyl-14C]-thymidine (14C-TdR), a microculture filtration plate and a radiochromatoscanner. Mitomycin, tamoxifen and 5-fluorouracil (5-FU) were tested against four human gastric cancer cell lines and HeLa cells. The tetrazolium-based colorimetric (MTT) assay underestimated cell inactivation by mitomycin in three cell lines compared with the cell count and the 14C-TdR assays. Inactivation by 5-FU in one cell line by 14C-TdR uptake was considerably lower than that by other methods. Thus neither the radio-labelled DNA precursor uptake nor the MTT assay is suitable for every anticancer drug but they are complementary.

Plasma cells in the bronchoalveolar lavage fluid of a patient with eosinophilic pneumonia. Morphologic proof of local production of antibodies.

We describe a case of eosinophilic pneumonia in which plasma cells appeared in bronchoalveolar lavage fluid (BALF). A 49-year-old man presented with wheezing, lung infiltrates, peripheral eosinophilia, and extremely high IgE levels in serum and BALF. A differential count of BALF revealed 56.6 percent lymphocytes and 1.3 percent plasma cells. The appearance of plasma cells suggests local maturation of B cells and represents a morphologic proof of local production of immunoglobulins. The increased number of lymphocytes suggests their role in B cell differentiation via the lymphokine network.

Modulation of accessory molecules on lung T cells.

Stimulation of T cells via the CD3/TCR complex is associated with the reduced expression of accessory molecules, a phenomenon called modulation. To investigate whether the modulation is implicated in the pathogenic mechanism of pulmonary disease, we determined the MFI of CD3, CD4 and CD8 on lung and blood lymphocytes in ten normal subjects and 54 patients with various pulmonary and extrapulmonary diseases. Although there were no significant differences in MFI of these accessory molecules on lung lymphocytes among the groups, MFI of CD3 on lung lymphocytes was significantly decreased compared with that on blood lymphocytes in all groups, demonstrating the modulation of CD3 on lung lymphocytes. Since it has been shown that T cells whose CD3/TCR is modulated are hyporesponsive to various mitogenic signals, our observation seems to represent another aspect of the mechanism whereby the local pulmonary milieu maintains the autoregulation of immune response.

Association of HLA-DR with sarcoidosis. Correlation with clinical course.

HLA-DR typing was performed in 58 Japanese patients with sarcoidosis. We found a significantly increased frequency of HLA-DRw52 (p less than 0.0007; pc less than 0.009) and DR5J (p less than 0.004; pc less than 0.05). (Corrected probability value is given as pc.) In 34 of 58 patients the disease resolved spontaneously. There was no significant difference between the frequency of DRw52 and the resolution rate of disease. The frequency of DR5J was increased significantly in the unresolved cases. Our results also suggest that DRw52 is concerned with onset of sarcoidosis and DR5J antigen has an effect on the clinical course of this disease.

Interaction of the Unc-51-like kinase and microtubule-associated protein light chain 3 related proteins in the brain: possible role of vesicular transport in axonal elongation.

We identified two mammalian ULK1 (Unc-51-like kinase involved in neurite extension) binding proteins by yeast two-hybrid screening. Both proteins showed high structural similarity to microtubule-associated protein (MAP) light chain 3 (LC3). One is identical to the Golgi-associated ATPase Enhancer of 16 kDa (GATE-16), an essential factor for intra-Golgi transport [39]. The other is identical to the gamma 2-subunit of GABA-A receptor associated protein (GABARAP) which has a possible role in receptor transport [46]. Using the yeast two-hybrid system and the in vitro GST pull-down assay, we found that the N-terminal proline/serine rich (PS) domain of ULK1 (amino acid 287-416) is required for ULK1-GATE-16 and ULK1-GABARAP protein interactions. However, the kinase activity of ULK1 affected neither ULK1-GATE-16 nor ULK1-GABARAP interaction. Immunohistochemical analysis using ULK1 and GABARAP antibodies showed that the ULK1 and the GABARAP proteins co-localized to many kind of neurons such as pyramidal cells of the hippocampus, mitral cells of the olfactory bulb, and Purkinje cells of the cerebellum. In HeLa cells, endogenous ULK1 and tagged GABARAP showed punctate structures in the cytosol, and were colocalized. These results suggest that the interaction of ULK1 and GABARAP is important to vesicle transport and axonal elongation in mammalian neurons.

CD8+ cell-dominant alveolitis in pulmonary sarcoidosis.

A 55-year-old woman had bilateral hilar lymphadenopathy and retinouveitis. Microscopic examination of a biopsy specimen from a mediastinal lymph node revealed noncaseating epithelioid cell granulomas. Since granulomatous diseases of infectious origin and sarcoid reaction were reasonably excluded, she was diagnosed as having pulmonary sarcoidosis. Bronchoalveolar lavage findings were atypical in that the ratio of helper T cells to suppressor T cells (CD4/8 ratio) was 0.5 in two separate examinations, despite a moderately increased proportion of lymphocytes. Immunohistochemical examination of the lymph node also showed a predominancy of suppressor T cells. The inversion of the CD4/8 ratio suggests the presence of heterogeneity in the immunoregulatory mechanism in pulmonary sarcoidosis and may have a prognostic significance.

Temperature rule for the speed of sound in water: a chemical kinetics model

Water forms three-dimensional polymeric structures due to the influence of hydrogen bonds and is fundamentally different from other substances. One of the simplest ways to analyze the structure of water in any system, such as hydration, is to measure the degree of compressibility, which can be determined from the speed of sound, by making use of the physical laws established by Newton and later perfected by Laplace. Although the speed of sound is strongly dependent on the temperature of a liquid, Laplace's equation does not refer to temperature in any of its terms. It is necessary, therefore, to determine the degree of temperature dependency. However, only approximate expressions of a fifth-order polynomial have been reported so far in the literature. In this paper, a universal method for describing the speed of sound from the perspective of physicochemical reaction kinetics is presented. It is shown that the speed of sound U [ms(-1)] changes with temperature T [K] according to a thermodynamically-derived formula given as U= exp(-A/T-BlnT+C) and that the motion and propagation phenomena of sound energy can also be regarded as chemical reactions.

Production of eicosapentaenoic acid by marine bacteria.

About 5,000 strains of marine microorganisms were screened for eicosapentaenoic acid (EPA)-producing ability, which was detected in 88 of them. All of the latter were found to be obligate aerobic, Gram-negative, motile, short rod-shaped bacteria. One strain, designated as SCRC-8132, showed a doubling time of 30 min at 25 degrees C and produced 20 mg/liter (4 mg/g dry cells) when cultured in a P-Y-M-Glucose medium for 18 h. The EPA to total fatty acids ratio was 24%. The strain produced 26 mg EPA/liter (15 mg/g dry cells) when cultured at 4 degrees C for 5 days, the EPA ratio being increased to 40%.

A cryptic melibiose transporter gene possessing a frameshift from Citrobacter freundii.

Wild-type Citrobacter freundii cannot grow on melibiose as a sole source of carbon. The melibiose transporter gene melB was cloned from a C. freundii mutant M4 that could utilize melibiose as a sole carbon source. Although the cloned melB gene is closely similar to the melB genes of other bacteria, it is cryptic because of a frameshift mutation. Site-directed mutagenesis was used to construct a functional melB gene by deleting one nucleotide, resulting in the production of an active melibiose transporter. The active MelB transporter could utilize Na(+) and H(+) as coupling cations to melibiose transport. The amino acid sequence of the C. freundii MelB was found to be most similar to those of Salmonella typhimurium and Escherichia coli MelB. These facts are consistent with the phylogenetic relationship of bacteria and the cation coupling properties of the melibiose transporters.

Hepatic artery embolization for inoperable hepatocellular carcinoma; prognosis and risk factors.

During a 7-year period in our hospital, 69 patients with inoperable hepatocellular carcinoma (HCC) underwent 111 courses of transcatheter hepatic artery embolization (TAE) and/or chemoinfusion with lipiodol. Patient survival was 0.5-37 months following therapy and the factors affecting prognosis were evaluated. Survival rates at 1, 2 and 3 years after TAE were 53%, 24% and 15%, respectively. Survival rates at 1, 2 and 3 years in relation to tumor size were 100%, 100% and 100% in 5 patients (tumor size less than 2 cm in diameter), 81%, 33% and 16% in 23 patients (2.1-5.0 cm), and 35%, 9% and 0% in 41 patients (greater than 5.1 cm). An analysis of prognostic factors showed that the size of the main tumor significantly influenced the prognosis following TAE (P less than 0.01), whereas the frequency of TAE, intrahepatic metastasis and the degree of liver dysfunction showed a slight correlation (P less than 0.1). These results suggest that TAE has a significant potential for becoming the first choice of treatment for patients with small multiple HCCs (less than 2 cm), provided that neither severe hepatic dysfunction nor a tumor thrombus in the main portal vein is present.