Biomedical subjects

C M Park

Publications and source records attributed to C M Park.

At least 19 recordsLinked to original sources

PubMed2006

Prognostic significance of beta-catenin in colorectal cancer with liver metastasis.

AIMS: A decreased expression of beta-catenin has been known to be associated with tumour metastasis. The prognostic value of beta-catenin expression in colorectal cancer (CRC) patients with liver metastasis was evaluated. MATERIALS AND METHODS: Seventy patients who underwent curative resection for CRC with liver metastasis were included. Tissue samples from normal colon mucosa, primary CRC and metastatic liver lesions were prepared in tissue microarrays, and were stained by immunohistochemistry with beta-catenin antibody. The beta-catenin expression of primary CRC tissues and metastatic liver tissues was analysed. RESULTS: A high expression of beta-catenin (score > 6) was observed in 42.0% and 21.9% of primary colorectal tissues and metastatic liver tissues, respectively. The beta-catenin expression in metastatic liver tissues was significantly lower than in primary CRC tissues (P = 0.022). The patients were classified into two groups according to the difference in the beta-catenin expression score between the primary CRC and the liver metastasis. Group A was defined as patients showing a remarkably decreased expression of beta-catenin in their metastatic liver tissue and group B was defined as patients showing a maintained or increased beta-catenin expression in their metastatic liver tissue in comparison with their primary CRC. The overall survival and disease-free survival rates were better in group B than in group A, and this was statistically significant (P = 0.02, P = 0.002). CONCLUSION: The decreased expression of beta-catenin in a metastatic liver lesion may be a poor prognostic marker in CRC with liver metastasis and further investigation is necessary.

Adult↗

PubMed2005

Antithyroid drug regimen for treating Graves' hyperthyroidism.

BACKGROUND: Antithyroid drugs are widely used in the therapy of hyperthyroidism. There are wide variations in the dose, regimen or duration of treatment used by health professionals. OBJECTIVES: To assess the effects of dose, regimen and duration of antithyroid drug therapy for Graves' hyperthyroidism. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (Central), MEDLINE, EMBASE, BIOSIS, CINAHL, HEALTHSTAR, Current Controlled Trials and reference lists. We contacted investigators and hand searched conference abstracts. Most recent search: July 2004. SELECTION CRITERIA: Randomised and quasi-randomised trials of antithyroid medication for Graves' hyperthyroidism were used. DATA COLLECTION AND ANALYSIS: Trial allocation to included, excluded and awaiting assessment categories was made by consensus. Two reviewers independently extracted data and assessed trial quality. Pooling of data for primary outcomes, and select exploratory analyses were undertaken. MAIN RESULTS: Twenty-three randomised trials involving 3115 participants were included. Overall the quality of trials as reported was poor; specifically in terms of allocation concealment, assessor blinding and loss to follow-up. Four trials examined the effect of duration of therapy on relapse rates of Graves' hyperthyroidism. In one trial using the Titration regimen, longer duration therapy (18 months) had significantly fewer relapses (37% versus 58%) than six month therapy (Odds ratio (OR) 0.42, 95% confidence interval (CI) 0.18 to 0.96). In one quasi-randomised trial using the Block-Replace regimen, there was no significant difference between the six and 12 month (relapses rates 41% versus 35%) arms of the study. Extending the duration of therapy to over 18 months was not associated with improved relapse rates (Peto OR 0.75, 95% CI 0.39 to 1.43). Twelve trials examined the effect of Block-Replace versus Titration regimen. The relapse rates were similar in both groups at 51% in the Block-Replace group and 54% in the Titration group (Peto OR 0.86, 95% CI 0.68 to 1.08). Participants reporting rashes (10% versus 5%) and withdrawing due to side effects (16% versus 9%) were significantly higher in the Block-Replace group compared to the Titration group respectively. Three studies considered the addition of thyroxine with continued low dose antithyroid therapy after initial therapy with antithyroid drugs. There was significant heterogeneity between the studies and the difference between the two groups were not significant (Odds ratio 0.58, 95% CI 0.05 to 6.21). Four studies considered the addition of thyroxine alone after initial therapy with antithyroid drugs. There was no significant difference in the relapse rates between the groups after 12 months follow-up with relapse rates being 31% (88/282) with thyroxine and 29% (82/284) with placebo (Peto OR 1.15, 95% CI 0.79 to 1.67). AUTHORS' CONCLUSIONS: The evidence (based on four studies) suggests that the optimal duration of antithyroid drug therapy for the Titration regimen is 12 to 18 months. The six month Block-Replace regimen was found to be as effective as the 12 month treatment in one quasi-randomised study. The Titration (low dose) regimen had fewer adverse effects than the Block-Replace (high dose) regimen and was no less effective in trials (based on 12 trials) of equal duration. Continued thyroxine treatment following initial antithyroid therapy does not appear to provide any benefit in terms of recurrence of hyperthyroidism. The incidence of hypothyroidism was not reported and there were no deaths reported in the study populations.

Antithyroid Agents↗

PubMed2004

Antithyroid drug regimen for treating Graves' hyperthyroidism.

BACKGROUND: Antithyroid drugs are widely used in the therapy of hyperthyroidism. There are wide variations in the dose, regimen or duration of treatment used by health professionals. OBJECTIVES: To assess the effects of dose, regimen and duration of antithyroid drug therapy for Graves' hyperthyroidism. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (Central), MEDLINE, EMBASE, BIOSIS, CINAHL, HEALTHSTAR, Current Controlled Trials and reference lists. We contacted investigators and hand searched conference abstracts. Most recent search: June 2002. SELECTION CRITERIA: Randomised and quasi-randomised trials of antithyroid medication for Graves' hyperthyroidism were used. DATA COLLECTION AND ANALYSIS: Trial allocation to included, excluded and awaiting assessment categories was made by consensus. Two reviewers independently extracted data and assessed trial quality. Pooling of data for primary outcomes, and select exploratory analyses were undertaken. MAIN RESULTS: Nineteen randomised trials involving 2233 participants were included. Overall the quality of trials as reported was poor; specifically in terms of allocation concealment, assessor blinding and loss to follow-up. Four trials examined the effect of duration of therapy on relapse rates of Graves' hyperthyroidism. In one trial using the Titration regimen, longer duration therapy (18 months) had significantly fewer relapses (37% vs 58%) than six month therapy (Odds ratio (OR) = 0.42, 95% confidence interval (CI) 0.18 to 0.96). In one quasi-randomised trial using the Block-Replace regimen, there was no significant difference between the six and 12 month (relapses rates 41% versus 35%) arms of the study. Extending the duration of therapy to over 18 months was not associated with improved relapse rates (Peto OR = 0.75, 95% CI 0.39 to 1.43). Ten trials examined the effect of Block-Replace versus Titration regime. Relapse rates were similar in both groups at 54% in the Block-Replace group and 58% in the Titration group (Peto OR = 0.83, 95% CI 0.63 to 1.10). Participants reporting rashes (11% versus 5%) and withdrawing due to side effects (16% versus 9%) were significantly higher in the Block-Replace group compared to the Titration group respectively. Three studies considered the addition of thyroxine after initial therapy with antithyroid drugs. There was significant heterogeneity between the studies and the difference between the two groups were not significant (Odds ratio = 0.58, 95% CI 0.05 to 6.21). REVIEWERS' CONCLUSIONS: The evidence (based on three studies) suggests that the optimal duration of antithyroid drug therapy for the Titration regimen is 12 to 18 months. The six month Block-Replace regimen was found to be as effective as the 12 month treatment in one quasi-randomised study. The Titration (low dose) regimen had fewer adverse effects than the Block-Replace (high dose) regimen and was no less effective in trials (based on 10 trials) of equal duration. The incidence of hypothyroidism was not reported and there were no deaths in the study populations.

Antithyroid Agents↗

PubMed2003

Antithyroid drug regimen for treating Graves' hyperthyroidism.

BACKGROUND: Antithyroid drugs are widely used in the therapy of hyperthyroidism. There are wide variations in the dose, regimen or duration of treatment used by health professionals. OBJECTIVES: To assess the effects of dose, regimen and duration of antithyroid drug therapy for Graves' hyperthyroidism. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (Central), MEDLINE, EMBASE, BIOSIS, CINAHL, HEALTHSTAR, Current Controlled Trials and reference lists. We contacted investigators and hand searched conference abstracts. Most recent search: June 2002. SELECTION CRITERIA: Randomised and quasi-randomised trials of antithyroid medication for Graves' hyperthyroidism were used. DATA COLLECTION AND ANALYSIS: Trial allocation to included, excluded and awaiting assessment categories was made by consensus. Two reviewers independently extracted data and assessed trial quality. Pooling of data for primary outcomes, and select exploratory analyses were undertaken. MAIN RESULTS: Nineteen randomised trials involving 2233 participants were included. Overall the quality of trials as reported was poor; specifically in terms of allocation concealment, assessor blinding and loss to follow-up. Four trials examined the effect of duration of therapy on relapse rates of Graves' hyperthyroidism. In one trial using the Titration regimen, longer duration therapy (18 months) had significantly fewer relapses (37% vs 58%) than six month therapy (Odds ratio (OR) = 0.42, 95% confidence interval (CI) 0.18 to 0.96). In one quasi-randomised trial using the Block-Replace regimen, there was no significant difference between the six and 12 month (relapses rates 41% versus 35%) arms of the study. Extending the duration of therapy to over 18 months was not associated with improved relapse rates (Peto OR = 0.75, 95% CI 0.39 to 1.43). Ten trials examined the effect of Block-Replace versus Titration regime. Relapse rates were similar in both groups at 54% in the Block-Replace group and 58% in the Titration group (Peto OR = 0.83, 95% CI 0.63 to 1.10). Participants reporting rashes (11% versus 5%) and withdrawing due to side effects (16% versus 9%) were significantly higher in the Block-Replace group compared to the Titration group respectively. Three studies considered the addition of thyroxine after initial therapy with antithyroid drugs. There was significant heterogeneity between the studies and the difference between the two groups were not significant (Odds ratio = 0.58, 95% CI 0.05 to 6.21). REVIEWER'S CONCLUSIONS: The evidence (based on three studies) suggests that the optimal duration of antithyroid drug therapy for the Titration regimen is 12 to 18 months. The six month Block-Replace regimen was found to be as effective as the 12 month treatment in one quasi-randomised study. The Titration (low dose) regimen had fewer adverse effects than the Block-Replace (high dose) regimen and was no less effective in trials (based on 10 trials) of equal duration. The incidence of hypothyroidism was not reported and there were no deaths in the study populations.

Antithyroid Agents↗

PubMed2003

MR findings of desmoplastic cerebral astrocytoma of infancy.

Desmoplastic cerebral astrocytoma of infancy (DCAI) presents as a large supratentorial mass consisting of a central cystic component and an enhancing solid component associated with peripheral dural attachment. We report the unusual MR findings of a DCAI that differed from previously reported cases in terms of the presence of calcification, which is not considered a feature of this tumor, and the absence of an enhancing peripheral dural component.

Astrocytoma↗

PubMed2002

The clinical relevance of sex hormone levels and sexual activity in the ageing male.

OBJECTIVES: To assess the changes in sex hormone levels with age and the relationship of sexual functioning to testosterone levels, evaluating serum testosterone levels and erectile function in men with lower urinary tract symptoms (LUTS). PATIENTS AND METHODS: The study included 213 men with LUTS (age range 31-78 years) who had no confirmed erectile dysfunction. Their serum total and free testosterone, and sex-hormone binding globulin (SHBG) levels were measured, and they completed the International Index of Erectile Function (IIEF) questionnaire. RESULTS: The total and free testosterone levels decreased and SHBG increased with age, but only the change in free testosterone and SHBG were statistically significant. The correlation with age was closer for free testosterone (r = - 0.356, P < 0.001) than for SHBG (r = 0.177, P = 0.010). Regression analysis of the five domain scores of the IIEF and three hormonal levels, after correcting for age, showed that free testosterone level was significantly correlated with erectile function (r = 0.2136, P = 0.005) and orgasmic function (r = 0.179, P = 0.020), but SHBG levels were significantly correlated only with orgasmic function (r = - 0.154, P = 0.046). Total testosterone levels showed no significant correlation with any of the five domains of the IIEF. CONCLUSIONS: Of the sex hormone levels, the change in free testosterone correlated most closely with ageing and had the closest correlation with sexual activity. Contrary to previous reports, free testosterone and SHBG levels were significantly correlated with orgasmic function and/or erectile function rather than sexual desire. A complete study of sex hormone levels is needed to evaluate patients with erectile dysfunction.

Adult↗

PubMed2001

Light and brassinosteroid signals are integrated via a dark-induced small G protein in etiolated seedling growth.

Plant growth and development are regulated through coordinated interactions between light and phytohormones. Here, we demonstrate that a dark-induced small G protein, pea Pra2, regulates a variant cytochrome P450 that catalyzes C-2 hydroxylation in brassinosteroid biosynthesis. The cytochrome P450 is dark-induced and predominantly expressed in the rapidly elongating zone of etiolated pea epicotyls, where Pra2 is also most abundant. Transgenic plants with reduced Pra2 exhibit a dark-specific dwarfism, which is completely rescued by exogenous brassinolide. Overexpression of the cytochrome P450 results in enhanced hypocotyl growth even in the light, which phenocopies the etiolated hypocotyls. We therefore propose that Pra2 and its orthologs are molecular mediators for the cross-talk between light and brassinosteroids in the etiolation process in plants.

Amino Acid Sequence↗

PubMed2001

Malignant mixed müllerian tumor of the ovary: imaging findings.

OBJECTIVE: We describe the imaging findings of malignant mixed müllerian tumor (MMMT) of the ovary, which have not previously been reported. MATERIALS AND METHODS: We experienced 13 cases of ovarian MMMT in eight patients. All patients underwent surgical resection and the MMMTs were confirmed pathologically. US (n = 8), CT (n = 8), and MRI (n = 1) examinations were performed before operation. Imaging features were analyzed retrospectively for bilaterality, tumor solidity (cystic or solid), size, and contrast enhancement of the tumor on CT and MRI. Presence of ascites and other evidence of peritoneal seeding, adjacent organ invasion, distant metastasis, and surgical staging were also evaluated. RESULTS: There were bilateral ovarian MMMTs in five patients and unilateral MMMTs in three patients. Two of the MMMTs were multiseptated cystic, and 11 were mixed (solid and cystic). The diameter of the largest dimension was less than 5 cm in one case, 5-10 cm in two cases, and larger than 10 cm in 10 cases. Dense homogeneous contrast enhancement of the solid component was seen in 11 mixed masses. Ascites were found in all patients. Other evidence of peritoneal seeding and direct invasion into adjacent organ such as the uterus or sigmoid colon was seen in five patients each. Pleural metastasis was present in one patient. Surgical stages were FIGO classification IIIb and IV in one patient each, and IIIc in six patients. CONCLUSION: Ovarian MMMTs usually present as aggressive, bilateral, large, solid and cystic tumors, combined with ascites, frequent peritoneal seeding, and adjacent organ invasion.

Adult↗

PubMed2001

Abdominopelvic actinomycosis involving the gastrointestinal tract: CT features.

PURPOSE: To assess the computed tomographic (CT) features of abdominopelvic actinomycosis involving the gastrointestinal tract. MATERIALS AND METHODS: CT scans were analyzed in 18 patients with pathologically proved abdominopelvic actinomycosis involving the gastrointestinal tract. Eight patients had a history of using intrauterine contraceptive devices. Bowel site, wall thickness, length, bowel involvement patterns, inflammatory infiltration, and features of peritoneal or pelvic mass, if present, were evaluated at CT. RESULTS: Of the gastrointestinal tract, the sigmoid colon was most commonly involved (50%). All patients showed concentric (n = 15) or eccentric (n = 3) bowel wall thickening, with a mean thickness of 1.2 cm and a mean length of 8.3 cm. The thickened bowel enhanced homogeneously in nine patients and heterogeneously in the other nine. Inflammatory infiltration was mostly diffuse and severe. In 17 patients, a peritoneal or pelvic mass (mean maximum diameter, 3.2 cm) was seen adjacent to the involved bowel and appeared to be heterogeneously enhanced in most cases; infiltration into the abdominal wall was seen in four patients. CONCLUSION: Actinomycosis should be included in the differential diagnosis when CT scans show bowel wall thickening and regional pelvic or peritoneal mass with extensive infiltration, especially in patients with abdominal pain, fever, leukocytosis, or long-term use of intrauterine contraceptive devices.

Actinomycosis↗

PubMed2000

A second photochromic bacteriophytochrome from Synechocystis sp. PCC 6803: spectral analysis and down-regulation by light.

It now appears that photosynthetic prokaryotes and lower eukaryotes possess higher plant phytochrome-like proteins. In this work, a second phytochrome-like gene was isolated, in addition to the recently identified Cph1 phytochrome, from the Synechocystis sp. PCC 6803, and its gene product was characterized photochemically. The open reading frame sll0821 (designated cph2 in this work) has structural characteristics similar to those of the plant phytochromes and the Synechocystis Cph1 with high amino acid sequence homology in the N-terminal chromophore binding domain. The predicted Cph2 protein consists of 1276 amino acids with a calculated molecular mass of 145 kDa. Interestingly, the Cph2 protein has two putative chromophore binding domains, one around Cys-129 and the other around Cys-1022. The Cph2 was overexpressed in E. coli as an Intein/CBD (chitin binding domain) fusion and in vitro reconstituted with phycocyanobilin (PCB) or phytochromobilin (PPhiB). Both the Cph2-PCB and Cph2-PPhiB adducts showed the typical photochromic reversibility with the difference spectral maxima at 643/690 and 655/701 nm, respectively. The Cys-129 was confirmed to be the chromophore binding residue by in vitro mutagenesis and Zn(2+) fluorescence. The microenvironment of the chromophore in Cph2 seems to be similar to that in plant phytochromes. The cph2 gene expression was dark-induced and down-regulated to a basal level by light, like the cph1 gene. These observations suggest that Synechocystis species have multiple photosensory proteins, probably with distinct roles, as in higher plants.

Amino Acid Sequence↗

PubMed2000

Chromophore-apoprotein interactions in Synechocystis sp. PCC6803 phytochrome Cph1.

The secondary, tertiary, and quaternary structures of the Synechocystis Cph1 phytochrome were investigated by absorption and circular dichroism spectroscopy, size exclusion chromatography, and limited proteolysis. The Cph1 protein was coexpressed with a bacterial thioredoxin in Escherichia coli, reconstituted in vitro with tetrapyrrole chromophores, and purified by chitin affinity chromatography. The resultant Cph1 holoproteins were essentially pure and had the specific absorbance ratio (SAR) of 0.8-0.9. Circular dichroism spectroscopy and limited proteolysis showed that the chromophore binding induced marked conformational changes in the Cph1 protein. The alpha-helical content increased to 42-44% in the holoproteins from 37% in the apoprotein. However, no significant difference in the secondary structure was detected between the Pr and Pfr forms. The tertiary structure of the Cph1 apoprotein appeared to be relatively flexible but became more compact and resistant to tryptic digestion upon chromophore binding. Interestingly, a small chromopeptide of about 30 kDa was still predominant even after longer tryptic digestion. The N-terminal location of this chromopeptide was confirmed by expression in E. coli and in vitro reconstitution with chromophores of the 32.5 kDa N-terminal fragment of the Cph1 protein. This chromopeptide was fully photoreversible with the spectral characteristic similar to that of the full-size Cph1 protein. The Cph1 protein forms dimers through the C-terminal region. These results suggest that the prokaryotic Cph1 phytochrome shares the structural and conformational characteristics of plant phytochromes, such as the two-domain structure consisting of the relatively compact N-terminal and the relatively flexible C-terminal regions, in addition to the chromophore-induced conformational changes.

Apoproteins↗

PubMed2000

Efficacy of allyl isothiocyanate in killing enterohemorrhagic Escherichia coli O157:H7 on alfalfa seeds.

Volatile compounds occurring in the essential oil of plants were tested for their efficacy in killing Escherichia coli O157:H7. Experiments using an agar disk assay revealed that exposure of the pathogen to 50 microl of eugenol, carvacrol, linalool, or methyl jasmonate in a 950-cc jar at 20, 37 or 47 degrees C for up to 48 h failed to inhibit colony formation. However, exposure to 8 microl of allyl isothiocyanate (AIT) (equivalent to 8.4 ppm in the air within the jar, if completely volatilized) resulted in more than a 7-log10 reduction in population of E. coli O157:H7 at 37 degrees C within 48 h; significant (P < or = 0.05) reduction in populations also occurred in the presence of 4 microl of AIT compared to 2 microl, which had no lethal affect. At 20 degrees C, the lethality of AIT was substantially less, although significant reduction occurred when disks were exposed to 8 or 10 microl of AIT compared to 4 or 6 microl and when exposed to 4 or 6 microl compared to 2 microl. Treatment with 10 microl of AIT for 5 h at 47 degrees C resulted in death of 6 log10 of E. coli O157:H7. The efficacy of AIT in killing E. coli O157:H7 on dry and wet alfalfa seeds was investigated. The pathogen, at an initial population of 2.7 log10 cfu/g of seed, was not recovered by direct plating (< 0.7 log10 cfu/g) or enrichment of wet seeds exposed to 50 microl of AIT/950-cc jar for 24 h at 37 or 47 degrees C. Exposure of dry seeds containing 2.9 log10 cfu of E. coli O157:H7 per g to an atmosphere containing 100 microl of AIT/950-cc jar (ca. 105 ppm AIT if completely volatilized) for 24 h at 47 degrees C did not eliminate viable E. coli O157:H7 cells. Unfortunately, the enhanced effectiveness of AIT in killing the pathogen on wet alfalfa seeds is offset by a dramatic reduction in seed viability. Nevertheless, the use of AIT as an alternative to chlorine for the purpose of killing E. coli O157:H7 and perhaps other pathogens on alfalfa seed holds promise. Factors that may influence conditions rendering increased sensitivity of E. coli O157:H7 to AIT without compromising seed viability should be investigated.

Escherichia coli O157↗

PubMed2000

Inter-domain crosstalk in the phytochrome molecules.

Phytochromes are bifunctional photoreceptors with a two-domain structure, consisting of the N-terminal photosensory domain and the C-terminal regulatory domain. The photo-induced Pr <--> Pfr phototransformation accompanies subtle conformational changes, primarily triggered by the apoprotein-chromophore interactions in the N-terminal domain. The conformational signals are subsequently transmitted to the C-terminal domain through various inter-domain crosstalks, resulting in the interaction of the activated C-terminal domain with phytochrome interacting factors. Thus the inter-domain crosstalks play critical roles in the photoactivation of the phytochromes. Protein phosphorylation, such as that of Ser-598, is implicated in this process by inducing conformational changes and by modulating inter-domain signaling.

Amino Acid Motifs↗

PubMed2000

Helical CT appearance of glomus tumor of the stomach.

Glomus tumor occurs only rarely in the stomach. This benign intramural mass is located most frequently in the distal half of the stomach. We experienced two cases of glomus tumor of the stomach which were examined with helical CT and were confirmed pathologically. Both tumors were well-marginated solitary lesions, located in the gastric antrum. On the early-phase helical CT, an intact overlying mucosa was demonstrated in both cases, and both tumors showed a dense homogeneous contrast enhancement, which persisted to the delayed phase.

Adult↗

PubMed2000

Survival of Escherichia coli O157:H7 in potato starch as affected by water activity, pH and temperature.

A study was done to determine the survival characteristics of Escherichia coli O157:H7 in potato starch powder as affected by aw (0.24-0.26, 0.51-0.52 and 0.75-0.78), pH (4.1 and 6.7) and temperature (4, 20 and 37 degrees C) over a 33-week storage period. Survival was enhanced as the aw decreased. The rate of death was higher as the storage temperature increased. Survival did not appear to be affected by pH. Since the composition of foods greatly affects the viability of E. coli O157:H7 at reduced aw, development of models to predict patterns of inactivation in a given food should be carried out using data generated from that food or one with very similar composition, aw and pH.

Escherichia coli O157↗

PubMed2000

Hepatic arterioportal shunts not directly related to hepatocellular carcinoma: findings on CT during hepatic arteriography, CT arterial portography and dual phase spiral CT.

AIM: To evaluate findings of arterioportal shunts not directly related to hepatocellular carcinoma (HCC) which were seen within third-order portal branches on computed tomography (CT) during hepatic arteriography (CTHA), arterial portography (CTAP), and dual phase spiral CT. MATERIALS AND METHODS: At CTHA in 112 patients, we examined third-order portal vein branches to find arterioportal shunts not directly related to HCC. Six cases were found. We evaluated the findings of these shunts on CTHA and investigated whether CTAP (n = 6) and dual phase spiral CT (n = 5) showed perfusion defects in the corresponding areas on arterioportal shunts. RESULTS: Five of six cases showed abrupt visualization of portal branches without visualization of the proximal portion of CTHA. Five of six cases showed no perfusion defect on CTAP and no hyperattenuating area on CTHA. Four of five cases showed no hyperattenuating area on hepatic arterial phase spiral CT. CONCLUSION: Arterioportal shunts not directly related to HCC and occuring within third-order portal branches mainly showed abrupt visualization of portal branches on CTHA. These occurred frequently without perfusion defects on CTAP and without a hyperattenuating area on CTHA and hepatic arterial phase spiral CT.Park, C. M. (2000). Clinical Radiology55, 465-470.

Adult↗

PubMed2000

Crystallization and preliminary X-ray crystallographic studies of response regulator for cyanobacterial phytochrome, Rcp1.

The key response-regulator gene of light regulation, rcp1, from Synechocystis sp. has been overexpressed, purified and subsequently crystallized using ammonium sulfate as a precipitant in forms suitable for X-ray crystallographic studies. A native data set was collected to a resolution of 2.5 A at cryogenic temperature. The crystals belong to the hexagonal space group P6(3), with unit-cell parameters a = b = 89.04 (5), c = 60.29 (3) A. The Matthews parameter suggests that Rcp1 crystallizes with two molecules per asymmetric unit.

Amino Acid Sequence↗

PubMed2000

Meniscal flounce on MR: correlation with arthroscopic or surgical findings.

The purpose of this study was to investigate the frequency of the meniscal flounce on MR imaging in patients who underwent arthroscopy or open surgery due to symptoms related to internal derangement of the knee, and to investigate associated findings in patients with meniscal flounce by comparing and analyzing the findings from MR imaging and surgery. MR images obtained from 116 knees before surgery were reviewed retrospectively. Seven medial menisci showed buckled, wavy flounce on sagittal MR images. None of the lateral menisci showed flounce. We reviewed the surgical records of all seven patients and the videotapes of six of the patients undergoing arthroscopy or open surgery. The frequency of flounce on sagittal MR images was 6.0% in the medial meniscus and was completely absent in the lateral meniscus. On coronal MR images, the truncated appearance of the affected meniscus was demonstrated in five patients, and a valgus deformity was seen in three patients. Five patients showed a moderate to large amount of joint effusion. On MR imaging and in surgery, ligament injuries were found in six patients (six medial collateral ligament injuries, five anterior cruciate ligament injuries, and two posterior cruciate ligament injuries). Non-specific synovitis was found in the one remaining patient. In the surgery of all seven patients, no tears were found at the meniscus itself showing flounce. In conclusion, the meniscal flounce seen on sagittal MR imaging can be a rare appearance of a transient distortion of a normal meniscus due to a valgus deformity caused by a MCL tear and/or due to an external rotation induced by cruciate ligament injury or positioning of knee joint within the magnet. The meniscal flounce should be interpreted carefully because it frequently appears truncated on the coronal scan and can simulate a meniscal tear.

Arthroscopy↗