Synchronous colorectal carcinoma: predisposing factors and characteristics.

AIM: Whether some diseases are related to the occurrence of synchronous colorectal carcinoma (sCRC) is unknown. Investigating the risk factors and presentation of sCRC could aid in the treatment of patients with colorectal cancer (CRC). The prognosis of sCRC compared with that of solitary CRC remains unclear. METHODS: A total of 17 093 CRC patients were recruited between 1st January 1995 and 31th December 2016. The risk factors of sCRC development were assessed using univariate and multivariate logistic regression. The effect of sCRC on survival was analysed using the multivariate Cox regression model. RESULTS: The prevalence of sCRC was 5.6% in this study. The independent risk factors of sCRC development were advanced age (P < 0.001), male sex (P < 0.001), hereditary cancer (P < 0.001), hypertension (P < 0.001) and liver cirrhosis (P = 0.024). Compared with solitary CRC, a higher number of patients with sCRC presented with an abnormal carcinoembryonic antigen (CEA) level (P = 0.011), anaemia (P < 0.001) and hypoalbuminemia (P < 0.001). Multivariate analysis revealed that sCRC was a significant factor for poor survival in patients at TNM Stage I [hazard ratio (HR) = 1.86; P < 0.001], Stage II (HR = 1.65; P < 0.001) and Stage III (HR = 1.40; P < 0.001). CONCLUSIONS: In addition to hypertension and liver cirrhosis, other risk factors for sCRC were identified in this study. The prognosis of patients with sCRC was significantly worse than that of those with solitary CRC through TNM Stages I to III. Anaemia, abnormal CEA and hypoalbuminemia were more commonly seen in patients with sCRC.

Long-term survival after hand-assisted laparoscopic approach of primary retroperitoneal mucinous cystadenocarcinoma in male: case report and review of literature.

BACKGROUND: Primary retroperitoneal mucinous cystadenocarcinoma (PRMC) is a rare disease and mostly occurs in females, and there are only three male cases described in the literatures without long-term follow-up. CASE REPORT: A 59-year-old male presented with a left retroperitoneal cystic mass (7.5 ´ 7 ´ 3 cm) that upwardly displaced the left kidney and caused abdominal discomfort. The tumor was totally excised by the hand-assisted laparoscopic method without complications or recurrence in a follow-up period of 79 months. The etiology from coelomic metaplasia of peritoneal epithelium was proved by a spectrum of diverse cells (benign, borderline malignant, and malignant cells) during pathological examination. RESULTS: This is the fourth male case of PRMC in the world with a favorable outcome after hand-assisted laparoscopic excision, and this is also distinct by the longest follow-up period in this disease entity. CONCLUSIONS: Because of its low-malignant potential and recurrence rate, surgical excision is still the best choice of treatment, but the least invasion method should be adopted in front.

Does the ratio and thickness of prevertebral soft tissue provide benefit in blunt cervical spine injury?

PURPOSE: Although many reports advocate computed tomography (CT) as the initial surveillance tool for occult cervical spine injury (CSI) at the emergency department (ED), the role of a lateral cervical spine radiograph (LCSX) has still not been replaced. We hypothesized that the increased width of the prevertebral soft tissue on an LCSX provides helpful information for selecting the high-risk patients who need to be evaluated with more accurate diagnostic tools. METHODS: This was a retrospective and consecutive series of injured patients requiring cervical spine evaluation who were first imaged with three-view plain films at the ED. The prevertebral soft tissue thickness (PVST) and ratio of prevertebral soft tissue thickness to the cervical vertebrae diameter (PVST ratio) were calculated on the LCSX. Suspicion of CSI was confirmed by either CT or magnetic resonance imaging (MRI) scans. RESULTS: A total of 826 adult trauma patients requiring cervical spine evaluation were enrolled. The C3 PVST and PVST ratio were significantly different between patients with or without upper cervical area injury (UCAI, 8.64 vs. 5.49 mm, and 0.394 vs. 0.276, respectively), and, likewise, the C6 PVST and PVST ratio for patients with or without lower cervical area injury (LCAI, 16.89 vs. 14.66 mm, and 0.784 vs. 0.749, respectively). The specificity was greater than 90 % in predicting UCAI and LCAI when combining these two parameters. CONCLUSIONS: This method maximizes the usefulness of LCSX during the initial assessment of a conscious patient with blunt head and neck injury, especially for the identification of high-risk patients requiring prompt CT or MRI; on the other hand, it prevents the overuse of these high-cost imaging studies as initial diagnostic tools.

The effects of Western music on postoperative pain in Taiwan.

Music is a method nurses can use to help relieve pain, however little is known about its effectiveness across cultures. In this study, Western music was tested for its effectiveness in reducing postoperative pain in 38 Taiwanese patients, and its acceptability was explored. A pretest and post-test experimental design was used with visual analogue scales to measure sensation and distress of pain. Before surgery, subjects were randomly assigned to receive tape recorded music or the usual care. Those who were assigned to the music group chose among 5 types of sedative music. On postoperative Day 1 and Day 2, the effectiveness of the tape-recorded music was investigated during 15 minutes of rest in bed. Patients were interviewed on Day 3 to determine their liking for the music, its calming effects, and the helpfulness of the music. Repeated measures analysis of variance showed a significant interaction between time and group in the distress of pain on Day 1, but not on Day 2, and in pain sensation on Day 2, but not Day 1. Subjects from Taiwan were similar to subjects in a previous study in the United States in their liking for the music, and in reports of the helpfulness of the music for pain sensation and distress, but fewer Taiwanese found the music calming, and they had different choices: more chose harp music and fewer chose jazz than subjects in the U.S. study, and some would prefer Buddhist hymns or popular songs heard in Taiwan. Findings support the use of culturally acceptable music in addition to analgesic medication for the sensation and distress of postoperative pain.

Human placental estradiol 17 beta-dehydrogenase: sequence of a histidine-bearing peptide in the catalytic region.

The amino acid sequence of an octapeptide from the catalytic site of human placental estradiol 17 beta-dehydrogenase (EC 1.1.1.62) was established by affinity-labeling techniques. The enzyme was inactivated separately by 12 beta-hydroxy-4-estrene-3,17-dione 12-(bromo[2-14C]acetate) and 3-methoxyestriol 16-(bromo[2-14C]acetate) at pH 6.3. The inactivations, in both cases, followed pseudo-first-order kinetics with half-times for the 12 beta and 16 alpha derivatives being 192 and 68 h, respectively. Both derivatives are known substrates that inactivate in a time-dependent, irreversible manner and that modify cysteine residues to form (carboxymethyl)cysteine and histidine residues to form either N tau- or N pi-(carboxymethyl)histidine. The inactivated enzyme samples were separately reduced, carboxymethylated, and digested with trypsin. The tryptic digests were applied to Sephadex G-50 and the radioactive N tau- and N phi-(carboxymethyl)histidine-bearing peptides identified. The peptides were further purified by cation-exchange chromatography and gel filtration. Final purification was achieved by HPLC prior to sequencing. It was determined that both steroid derivatives modified either of the two histidine residues in the peptide Thr-Asp-Ile-His-Thr-Phe-His-Arg. These histidines are different from a histidine that was previously shown to be alkylated by estrone 3-(bromoacetate) and that was presumed to proximate the A ring of the bound steroid. It is concluded that the two histidine residues identified in the present study proximate the D ring of the steroid as it binds at the active site and may participate in the hydrogen transfer effected by human placental estradiol 17 beta-dehydrogenase.

The amino acid sequence of Escherichia coli cyanase.

The amino acid sequence of the enzyme cyanase (cyanate hydrolase) from Escherichia coli has been determined by automatic Edman degradation of the intact protein and of its component peptides. The primary peptides used in the sequencing were produced by cyanogen bromide cleavage at the methionine residues, yielding 4 peptides plus free homoserine from the NH2-terminal methionine, and by trypsin cleavage at the 7 arginine residues after acetylation of the lysines. Secondary peptides required for overlaps and COOH-terminal sequences were produced by chymotrypsin or clostripain cleavage of some of the larger peptides. The complete sequence of the cyanase subunit consists of 156 amino acid residues (Mr 16,350). Based on the observation that the cysteine-containing peptide is obtained as a disulfide-linked dimer, it is proposed that the covalent structure of cyanase is made up of two subunits linked by a disulfide bond between the single cystine residue in each subunit. The native enzyme (Mr 150,000) then appears to be a complex of four or five such subunit dimers.

Spatial relationship of steroid and cofactor at the active site of human placental estradiol 17 beta-dehydrogenase.

Two affinity-labeling steroids (2-bromo[2'-14C]acetamidoestrone methyl ether and 16 alpha-bromo[2'-14C]acetoxyestradiol 3-methyl ether) which bear their reagent groups on the A- and D-ring of the molecule, respectively, and which are both substrates, have been used to elucidate spatial relationships of steroid and cofactor as they undergo the reversible binding step at the active site of human placental estradiol 17 beta-dehydrogenase. The 2-derivative alkylates its evolutive cofactor (NADH) in the presence of the enzyme but not in the absence of enzyme. The rate of cofactor alkylation increases with increasing quantities of enzyme and is slowed by estrone which competes for the enzyme-active site. To the contrary, the 16 alpha-derivative does not detectably alkylate its evolutive cofactor (NAD+). The product of cofactor alkylation by 2-bromoacetamidoestrone methyl ether was treated to effect hydrolytic removal of the adenine moiety from the remainder of the cofactor, reduction of the steroid 17-keto group, and crystallization. The final crystalline product has been identified as 2-[2'-6N-adenyl]acetamidoestradiol 3-methyl ether (IUPAC name: N-(3-methoxy-17 beta-hydroxy-1,3,5(10)-estratrien-2-yl)-2-(purin-6-ylamino) acetamide) by ultraviolet, infrared, NMR, and mass spectral analysis.

The amino acid sequence of yeast enolase. Preparation and characterization of peptides produced by chemical and enzymatic fragmentation.

Yeast enolase was subjected to chemical and enzymatic fragmentation, and the individual peptides produced were isolated by gel filtration and ion exchange chromatography. The chemical fragmentation was achieved by cleavage at the single cysteine residue with 2-nitro-5-thiocyanobenzoic acid, or at the 5 methionine residues with cyanogen bromide. The assignment of the two 2-nitro-5-thiocyanobenzoic acid fragments to the NH2-terminal or COOH-terminal regions (designated C1 and C2, respectively) of the enolase subunit could be done unequivocally on the basis of NH2-terminal and COOH-terminal analysis, and the same was the case for the NH2-terminal and COOH-terminal cyanogen bromide peptides (designated M1 and M6, respectively). From a comparison of the CNBr peptides from enolase with those from Fragment C1, the identity of methionine peptides M4, of which only the NH2-terminal half is present in C1, and M5, which along with M6 is missing in C1, could also be established. The major enzymatic fragmentation was achieved by tryptic cleavage at the 14 arginine residues after acetylation of the lysine residues. Based on overlaps with methionine peptides, most of the arginine peptides could be ordered in proper sequence during the early phases of the work. Because of the size of several of the primary fragments, secondary cleavages were required for optimal sequencing data. These secondary cleavages were accomplished by digestion with Staphylococcus aureus protease, or by tryptic cleavage at cysteine after aminoethylation.

Synthesis of 2-bromoacetamidoestrone methyl ether and study of the steroid-binding site of human placental estradiol 17 beta-dehydrogenase.

To characterize further the active site of human placental estradiol 17 beta-dehydrogenase (EC 1.1.1.62), we have synthesized 2-bromoacetamidoestrone methyl ether. The affinity-labeling steroid is a substrate for the homogeneous enzyme. It inactivates the enzyme in a time-dependent, irreversible manner which follows pseudo-first order kinetics. Further, inactivation conducted with varying steroid concentration displays saturation kinetics. When 1.7 x 10(-6) M enzyme is inactivated by 2.6 x 10(-4) M 2-bromoacetamidoestrone methyl ether, the presence of an equimolar concentration of estradiol or 5.2 x 10(-4) M concentrations of NAD+, NADP+, or NADPH markedly slow the rate of inactivation. Bromoacetate (2.6 x 10(-4) M) does not inactivate the enzyme. After inactivation with 2-bromo[2'-14C]acetamidoestrone methyl ether, amino acid analysis reveals carboxymethylated derivatives of cysteine, histidine, and lysine containing 65, 25, and 8%, respectively, of the total incorporated carboxymethyl groups. The presence of estradiol, NADP+, or NADPH clearly inhibits alkylation of cysteinyl and histidyl residues and slows the rate of enzyme inactivation. Protection of these residues by both estradiol and NADPH suggests that they may actually be in the cofactor region of the active site, that this region is close to the steroid A-ring, and that binding of cofactor, by physical interposition, denies the reagent-bearing steroid access to these residues.

Structure of the steroid-binding site of human placental estradiol-17beta-dehydrogenase.

We recently demonstrated that human placental estradiol-17beta-dehydrogenase possesses a histidyl residue in the catalytic region of the active site by affinity-labeling studies with 16alpha-bromoacetoxyestradiol-3-methyl ether. We now report the synthesis of 12beta-bromoacetoxy-4-estrene-3,17-dione and its use in affinity labeling of the enzyme. The steroid was synthesized by incubation of 4-estrene-3,17-dione with Colletotrichum gloesporioides. The product was recrystallized from ethanol and structure assured by IR and NMR spectroscopy. The steroid is a substrate, which indicates that it binds at the active site. When the enzyme is incubated with a 150-fold molar excess of 12beta-bromoacetoxy-4-estrene-3,17-dione in potassium phosphate buffer at pH 7.0, the enzyme is inactivated in a time-dependent, irreversible manner. Inactivation follows pseudo-first-order kinetics with a half life of 18 hours. Analysis of a hydrolysate of the enzyme after inactivation with 12beta-bromo[2'-3H]acetoxy-4-estrene-3,17-dione reveals tritiated 1-, 3-, and 1,3-dicarboxymethylhistidine. The affinity labeling of a histidyl enzyme residue by both 16alpha- and 12beta-bromoacetoxy steroids localizes that residue near the point of catalysis and suggests that it may participate in the catalytic event.

Crystallization of human placental estradiol 17beta-dehydrogenase. A new method for crystallizing labile enzymes.

Estradiol 17beta-dehydrogenase from human placenta has been crystallized by a new technique, herein referred to as electrophoretic diffusion. This is the first crystallization of an enzyme from human placenta as well as the first crystallization of any steroid-converting enzyme of human source. A solution of the enzyme (specific activity 7.1 units/mg) in 1.5 ml of Tris-barbituric acid buffer, pH 7.0, containing 20% glycerol as stabilizer, was placed in an electrophoresis tube and the tube was closed at both ends with a dialysis membrane which permits the passage of substances of molecular weight less than 18,000. The tube was placed in a gel electrophoresis apparatus and the reservoirs filled with the Tris-barbituric acid buffer. A potential of 100 V was applied for 12 hours, then raised to 200 V for another 12 hours, and finally to 300 V until opalescence appeared at the bottom of the tube. Activity measurements showed that more than 90% of the enzyme had concentrated in the bottom 0.15-ml portion of the solution. When this section of the solution was removed and kept overnight at 4 degrees, gross and microscopic examination revealed a heavy crop of crystals which possessed a specific activity of 7.2 units/mg. The specific activity remained constant throughout three recrystallizations. The crystalline enzyme displayed a single band by analytical and sodium dodecyl sulfate-polyacrylamide gel analysis. Crystals of enzyme of high specific activity could also be obtained from an enzyme sample initially possessing a specific activity of only 4.5 units/mg. The new technique should be appliable for the crystallization of other labile enzymes and receptor proteins which have so far resisted crystallization by conventional methods.

Purification of human placental estradiol 17 beta-dehydrogenase study of the steroid-binding site.

Human placental estradiol 17 beta-dehydrogenase has been purified by affinity chromatography. The purified enzyme is homogenous by polyacrylamide-gel electrophoresis. To study topography of the steroid-binding site, 16 alpha-bromoacetoxyestradiol 3-methyl ether was synthesized with estriol 3-methyl ether, bromoacetic acid, or [2-3H] bromoacetic acid and dicyclohexylcarbodiimide. The steroid alkylates cysteine, histidine, methionine, and tryptophan under physiologic conditions. Being a substrate of the enzyme, it must bind at the steroid-binding site. The steroid inactivates the enzyme in a time-dependent, irreversible manner. Inactivation of the enzyme by excess 16 alpha-bromoacetoxyestradiol 3-methyl ether follows pseudo--first-order kinetics with t1/2 = 1.5 hours. Amino acid analysis reveals that a histidyl residue is carboxymethylated. Estradiol-17 beta slows inactivation; 2-mercaptoethanol stops it. Previous studies have shown a histidyl residue also present at the catalytic region of the active site of 20 beta-hydroxysteroid dehydrogenase from Streptomyces hydrogenans. It is tempting to consider that these histidyl residues may be an essential component for the dehydrogenation of the steroid substrates.

Synthesis of 16alpha-bromoacetoxyestradiol 3-methyl ether and study of the steroid binding site of human placental estradiol 17beta-dehydrogenase.

Homogeneous estradiol 17beta-dehydrogenase (EC 1.1.1.62) was prepared from human placenta by affinity chromatography and the steroid binding site was studied with affinity-labeling techniques. 16alpha-Bromoacetoxyestradiol 3-methyl ether and the tritated compound were synthesized by condensation of estriol 3-methyl ether with bromoacetic acid or [2-3H]bromoacetic acid in the presence of dicyclohexylcarbodiimide. 16alpha-Bromoacetoxyestradiol 3-methyl ether is stable in 0.01 M phosphate buffer at pH 7.0, 25 degrees, for at least 24 hours. It alkylates cysteine, histidine, methionine, lysine, and tryptophan under physiological conditions. The steroid is a substrate of estradiol 17beta-dehydrogenase, thus it must bind at the steroid binding site. The inactivation of estradiol 17beta-dehydrogenase by 150-fold molar concentrations of 16alpha-bromoacetoxyestradiol 3-methyl ether follows pseudo-first order kinetics with a half-time of 1.5 hours. Estradiol-17beta, NADH, and NADPH slow the rate of inactivation. 2-Mercaptoethanol in molar concentrations 50-fold that of 16alpha-bromoacetoxyestradiol 3-methyl ether stops the inactivation, but does not reverse it. 16alpha-Bromoacetoxyestradiol 3-methyl ether alkylates both NADH and NADPH; the presence of small amounts of enzyme markedly increases the rate of this alkylation. When the enzyme is inactivated with 16alpha-[2-3H]bromoacetoxyestradiol 3-methyl ether, amino acid analysis of acid hydrolysates reveals 3-carboxymethylhistidine and 1,3-dicarboxymethylhistidine. Comparison of 28 and 51% inactivated samples indicates that, as inactivation proceeds, the total amount of 3-carboxymethylhistidine decreases, while 1,3-dicarboxymethylhistidine increases, suggesting that the former is converted to the latter by a second alkylation step. When the enzyme is inactivated in the presence of a large excess of NADPH, only 1,3-dicarboxymethylhistidine is found. From the present study it is concluded that estradiol 17beta-dehydrogenase has a histidyl residue present in the catalytic region of the active site as does the previously studied 20beta-hydroxysteroid dehydrogenase.