Sonographic appearance of lipoma of the inferior vena cava

Lipomas of the major central veins are rare, and their sonographic features have rarely been reported. We report a case in which a lipoma of the inferior vena cava (IVC) was incidentally identified during liver sonography in a 68-year-old man. Sonography of the upper abdomen revealed coarsening of the liver echotexture, with a relatively small liver and atrophy of the right hepatic lobe. A 2-cm hypoechoic hepatic nodule was visualized in segment IV. Sonography also showed a 2.2- x 1.8-cm, highly echogenic, homogeneous nodule in the hepatic segment of the IVC at its junction with the right atrium. The lumen of the IVC was partially occluded. The CT and MRI appearances of the IVC lesion were consistent with a lipoma, which was not treated because there was no clinical evidence of obstruction. Histopathologic analysis following a sonographically guided biopsy of the liver nodule revealed hepatocellular carcinoma, which was treated by percutaneous ethanol injection.

Response of amoeboid and differentiating ramified microglia to glucocorticoids in postnatal rats: a lectin histochemical and ultrastructural study

After glucocorticoid injection(s), the number of amoeboid microglial cells (AMC) in the corpus callosum labelled by lectin was markedly reduced when compared with the corresponding control rats. In rats killed at the age of 7 days, all the labeled cells differentiated to become ramified microglia. Ultrastructurally, the AMC in glucocorticoid-injected rats were extremely vacuolated and showed increased lipid droplets. Furthermore, the cells displayed varied lectin labelling patterns especially at both the trans saccules of the Golgi apparatus and lysosomes. In differentiating ramified microglia, massive cellular debris and lectin-stained vesicles or vacuoles were observed; some of the latter appeared to fuse with the plasma membrane. The most striking feature after glucocorticoid (GCC) treatment was the complete diminution of lectin labelling at the Golgi saccules in some differentiating ramified microglia. The present results have demonstrated different effects of glucocorticoids on AMC and differentiating ramified microglia. The differential response of AMC and differentiating ramified microglia to the immunosuppressive drugs may be attributed to the fact that these cells in the postnatal brains subserve different functions or that they are at different differentiation stages. In other words, the sensitivity of microglial cells to the immunosuppressive drugs is dependent upon the stage of cell maturation/differentiation.

Sonographic features of xanthogranulomatous pyelonephritis

PURPOSE

The purpose of this study was to describe the various sonographic features of xanthogranulomatous pyelonephritis (XGP).

METHODS

We retrospectively reviewed the CT, sonographic, and medical records of patients diagnosed with XGP from January 1981 to December 1998. Twenty-seven patients for whom XGP was histopathologically confirmed were included in the study. There were 12 men and 15 women, with an age range of 21-86 years (mean, 57 years). All patients had undergone sonography of the kidneys. The renal size, shape, and outline were recorded. The presence of perinephric fluid accumulation, of obstructive uropathy, or of internal echoes in the dilated collecting system and the echotexture of the renal parenchyma were documented.

RESULTS

We categorized the XGP into 4 groups on the basis of the sonographic features: (1) diffuse hydronephrotic, 12 patients (44%); (2) diffuse parenchymal, 9 patients (33%); (3) diffuse contracted, 4 patients (15%); and (4) segmental or focal, 2 patients (7%). A localized perinephric fluid collection was present in 4 patients (15%). The preoperative sonographic diagnoses were pyonephrosis (n = 14, 52%), renal pelvic tumor with possible associated infection (n = 5, 19%), renal parenchymal mass (n = 2, 7%), hydronephrosis (n = 2, 7%), and chronic pyelonephritis with renal atrophy (n = 4, 15%). XGP was considered a possible diagnosis in only 11 patients (41%).

CONCLUSIONS

XGP has no specific sonographic features but is suggested by parenchymal thinning and hydronephrosis, sonographic signs of chronic obstructive uropathy caused by stones; echoes in the dilated collecting system; and a perinephric fluid collection. CT, needle biopsy, or both are recommended to further evaluate and confirm sonographically suspected XGP.

The role of high-resolution ultrasonography in management of calcific tendonitis of the rotator cuff

This article predicts the possibility of resorption of the calcific plaques in the shoulder using high-resolution ultrasonography (HRUS) and color Doppler ultrasound (CDUS), and evaluates the therapeutic effect of US-guided fine-needle multiple punctures of the calcific plaque. A total of 100 patients with calcific tendenosis were divided into 3 groups: In group 1, patients having chronic shoulder pain received conservative treatment; in group 2, patients having acute exacerbation of shoulder pain also received conservative treatment; and group 3 patients received US-guided fine-needle multiple punctures or aspiration. In CDUS, all images were classified as grade 0 (no color flow signals), grade 1 (weak spotty color flow signal), grade 2 (few rod-like color flow signals), grade 3 (many rod-like or linear color flow signals). In the follow-up study, marked improvement of patients' clinical condition with more than 50% size reduction of calcific plaque was defined as an effective treatment. There was no significant difference between group 1 and group 3 (p = 0.558) in CDUS, but there was a significant difference between group 1 and group 2 (p = 0.000), and group 2 and group 3 (p = 0.000) on the basis of classification of grade < 1 and grade > or = 1. There was also significant difference in the follow-up result of effective management between group 1 and group 3 (p = 0.000), and group 1 and group 2 (p = 0.000). In conclusion, HRUS with CDUS proved to be a good modality in evaluating the possibility of resorption of shoulder calcification and, if CDUS > or = grade 1 in calcific tendonitis, we highly recommend conservative treatment with regular follow-up. On the other hand, if CDUS < grade 1, fine-needle repeated puncture could be considered as an effective alternative treatment.

Lithopedion

Lithopedion is a rare obstetrical outcome of an undiagnosed and untreated advanced abdominal pregnancy, mostly found incidentally. We present a case of lithopedion. In a 76 year-old female suffering from cervical neoplasm, total abdominal hysterectomy was performed for the lesion and the lithopedion was found incidentally. The patient's history was unremarkable, and laboratory tests were normal. The patient recalled having experienced a severe abdominal pain about 50 years before. Her physician had felt "a benign tumor" in her pelvis at that time, indicating that the stone child had retained in the maternal peritoneal cavity for 50 years.

Preparation of activated carbons from corn cob catalyzed by potassium salts and subsequent gasification with CO2

In the present study, granular activated carbons were prepared from agricultural waste corn cob by chemical activation with potassium salts and/or physical activation with CO2. Under the experimental conditions investigated, potassium hydroxide (KOH) and potassium carbonate (K2CO3) were effective activating agents for chemical activation during a ramping period of 10 degrees C/min and subsequent gasification (i.e., physical activation) at a soaking period of 800 degrees C. Large BET surface areas (>1,600 m2/g) of activated carbons were thus obtained by the combined activation. In addition, this study clearly showed that the porosity created in the acid-unwashed carbon products is substantially lower than that of acid-washed carbon products due to potassium salts left in the pore structure.

Sensitivity of diffusion-weighted magnetic resonance imaging in the diagnosis of acute lacunar infarcts

BACKGROUND AND PURPOSE

Heightened interest in the early diagnosis and treatment of acute stroke challenges neuroimaging specialists to optimize available modalities and to develop new techniques for the evaluation of cerebrovascular disease. The purpose of this study was to evaluate the sensitivity of diffusion-weighted (DW) magnetic resonance (MR) imaging in detecting early small infarcts and in differentiating acute from nonacute small infarcts when conventional MR imaging demonstrates multiple small infarcts.

METHODS

Thirty-eight consecutive patients with a clinical diagnosis of lacunar infarcts (20 men and 18 women, aged 50-79 yr) who underwent DW MR imaging within 3 days of symptom onset were enrolled in this study. All patients underwent both conventional fast spin-echo (FSE) MR imaging and DW MR imaging. Apparent diffusion coefficient (ADC) maps were also acquired. All patients had at least one of the following classic lacunar syndromes: pure motor hemiparesis, ataxic hemiparesis, dysarthria-clumsy hand, pure sensory stroke, and sensorimotor stroke.

RESULTS

Thirty-six patients (40 acute lesions) had focal areas of high intensity on DW MR imaging associated with their clinical symptoms. Acute lacunar infarcts were seen on DW MR imaging as bright areas of decreased ADC ratio (range 0.31-0.85, mean 0.64). Lesion conspicuity with DW MR imaging was superior to that with FSE in 33 acute lesions. In four patients with small hyperacute (within 6 hours) infarcts, DW MR imaging was particularly sensitive for infarcts that were not visible on FSE sequences. The sensitivity of DW MR imaging and ADC map for acute lacunar infarcts was 95%, specificity 94%, positive predictive value 97%, negative predictive value 90%, and accuracy 95%. In 15 patients with both acute and nonacute old small infarcts, DW MR imaging and ADC map could easily distinguish the new infarct from adjacent old ones, although this distinction was difficult to make with FSE.

CONCLUSIONS

DW MR imaging accompanied by ADC map is a sensitive diagnostic modality for hyperacute and acute lacunar infarcts. It is also sensitive in distinguishing fresh small infarcts from adjacent multiple old infarcts.

Magnetic resonance imaging appearance of intradural spinal lipoma

Intradural spinal lipoma not associated with spinal dysraphism is a rare tumor often presenting with nonspecific symptoms and indolent clinical course. Its intradural location and fat component is the key for proper preoperative diagnosis, which could hardly be made by traditional imaging studies including plain film and myelography. Both CT and MRI can reveal the fat component of the tumor, but MRI is superior to CT in demonstrating its relationship with adjacent normal nerve tissue. We report a 32-year-old man who had back pain for years and the symptom progressed rapidly in recent two months. MRI revealed an intradural tumor at T12 level with high signal intensity on both T1- and T2-weighted images. The signal intensity dropped dramatically with fat saturation technique, which confirmed fat as its main component. The patient received surgery and the tumor was proved to be an intraspinal lipoma.

Differential coronary artery calcification detected by electron beam computed tomography as an indicator of coronary stenosis among patients with stable angina pectoris

BACKGROUND

The detection of coronary artery calcification by electron beam computed tomography (EBCT) has been suggested as an indicator of atherosclerosis and coronary artery disease (CAD). There is no consensus on the correlation between coronary calcification and angiographically significant stenosis on an artery-by-artery basis.

OBJECTIVE

To examine the relationship between coronary calcification score (CCS) and the presence of significant CAD on an artery-by-artery basis in patients with stable angina pectoris.

METHODS AND RESULTS

EBCT and coronary angiogram (CAG) were evaluated in 71 patients with stable angina and in nine control subjects. The CCSs of each of the four major coronary arteries were highest in patients with significant CAD (n=43), followed by patients with insignificant CAD (n=5), patients with syndrome X (n=23) and control subjects, respectively. Calcification scores of the four major coronary arteries appeared to have different predictive power for significant stenosis on the same vessel. For left main (LM) and left anterior descending (LAD) coronary arteries, CCSs of vessels with significant stenoses were not different from those without significant stenoses (values expressed as medians: LM 0 versus 1; LAD 98.5 versus 70; not significant). Calcification scores of left circumflex (LCX) and right coronary arteries (RCA) were significantly higher in vessels with significant stenosis (LCX 49.5 versus 0; RCA 53 versus 1; P<0.05). CCSs appeared to be moderately useful to predict significant stenoses in these two vessels (areas under receiver operating characteristic curves: LCX 0.68+/-0.08, 95% CI 0.52 to 0.81; RCA 0.71+/-0.08, 95% CI 0.55 to 0.84).

CONCLUSIONS

The CCSs of RCA and LCX arteries, but not those of LM and LAD arteries, may predict significant angiographic stenosis on an artery-by-artery basis among patients with stable angina pectoris.

Primary structure and developmental expression of zebrafish sodium channel Na(v)1.6 during neurogenesis

A zebrafish sodium channel cDNA encoding a 1949-amino acid polypeptide, Na(v)1.6, was isolated. Two transcripts were detected in zebrafish adult brain but not in cardiac or skeletal muscle. The RNase protection analysis confirmed the neural specificity of zebrafish Na(v)1.6 24 hours postfertilization (hpf) Na(v)1.6 was expressed in the trigeminal ganglion, anterior and posterior lateral line ganglia, rhombomeres, and Rohon-Beard neurons. This preferential localization suggests that Na(v)1.6 plays an important role in tactile sensitivity. The abundance of zebrafish Na(v) 1.6 mRNA in the central and peripheral nervous systems increased markedly between 48 and 72 hpf, during the maturation of the nervous system.

Characterization of activated carbons prepared from sugarcane bagasse by ZnCl2 activation

Activated carbons were prepared from the agricultural waste of sugarcane bagasse by the chemical activation with zinc chloride (ZnCl2) at the activation temperature of 500 degrees C with soaking time of 0.5 hour. The influence of activation parameters on the final carbon products was examined by varying the impregnation ratio (i.e., mass ratio of added ZnCl2 to bagasse) and bagasse size. The physical properties of carbon products were characterized by nitrogen adsorption/desorption isotherms (at 77 K) and helium displacement method. The surface area and pore volume of carbons were thus obtained by the BET equation and t-plot method. Also, the particle density and porosity of carbons were estimated by the total pore volume and true density. The increases of the values of surface area and pore volume are approximately proportional to the impregnation ratio. The microporous carbon product with the BET surface area of 905 m2/g and total pore volume of 0.44 cm3/g was obtained in the present study. Further, the adsorption isotherms of two acid dyes from aqueous solutions onto the carbon products were performed at 30 degrees C. The results show that the adsorption isotherms of acid dyes with high molecular weight or large molecular size on the microporous adsorbents of activated carbons are plateau forms, indicating multilayer adsorptions, which may be attributed to the steric hindrance of the adsorbate molecules.

Phosphorylation of Ser363, Thr370, and Ser375 residues within the carboxyl tail differentially regulates mu-opioid receptor internalization

Prolonged activation of opioid receptors leads to their phosphorylation, desensitization, internalization, and down-regulation. To elucidate the relationship between mu-opioid receptor (MOR) phosphorylation and the regulation of receptor activity, a series of receptor mutants was constructed in which the 12 Ser/Thr residues of the COOH-terminal portion of the receptor were substituted to Ala, either individually or in combination. All these mutant constructs were stably expressed in human embryonic kidney 293 cells and exhibited similar expression levels and ligand binding properties. Among those 12 Ser/Thr residues, Ser(363), Thr(370), and Ser(375) have been identified as phosphorylation sites. In the absence of the agonist, a basal phosphorylation of Ser(363) and Thr(370) was observed, whereas [d-Ala(2),Me-Phe(4),Gly(5)-ol]enkephalin (DAMGO)-induced receptor phosphorylation occurs at Thr(370) and Ser(375) residues. Furthermore, the role of these phosphorylation sites in regulating the internalization of MOR was investigated. The mutation of Ser(375) to Ala reduced the rate and extent of receptor internalization, whereas mutation of Ser(363) and Thr(370) to Ala accelerated MOR internalization kinetics. The present data show that the basal phosphorylation of MOR could play a role in modulating agonist-induced receptor internalization kinetics. Furthermore, even though mu-receptors and delta-opioid receptors have the same motif encompassing agonist-induced phosphorylation sites, the different agonist-induced internalization properties controlled by these sites suggest differential cellular regulation of these two receptor subtypes.

Molecular basis of the Kell-null phenotype: a mutation at the splice site of human KEL gene abolishes the expression of Kell blood group antigens

The Kell blood group system is polymorphic, and 23 antigens have been defined to date. The Kell antigens are located on a single red cell transmembrane glycoprotein, encoded by the 19 exons of the KEL gene. The different Kell phenotypes result from point mutations leading to amino acid changes in the Kell glycoprotein. An unusual phenotype, which is defined as the complete lack of all of the Kell antigens, has been identified and designated as the Kell-null or Ko phenotype. The coding region of the KEL gene of the Ko individual showed a normal KEL2/KEL4/KEL7 gene sequence; nevertheless, a G to C mutation at the splice donor site (5' splice site) of intron 3 was found to be present as a homozygote in the individual. The mutation destroys the conserved GT sequence of the splice donor site. Reverse transcription-polymerase chain reaction analysis showed the absence of the complete KEL mRNA. Instead, a major transcript with the exon 3 region skipped was found. The exon 3 of the KEL gene encodes the transmembrane domain of the Kell glycoprotein, and a transcript without exon 3 is predicted to have a premature stop codon that abolishes the translation of C-terminal segment. The segment contains all of the known positions responsible for characterizing different Kell antigens, and this explains the lack of all Kell antigens in Ko red cells.

Sequential MR studies of a patient with white matter disease presenting psychotic symptoms: ADEM versus single-episode MS

Acute disseminated encephalomyelitis (ADEM) and multiple sclerosis (MS) are both demyelinating white matter disorders. It is difficult to differentiate ADEM from single episode MS because of the similar clinical presentation, cerebral spinal fluid (CSF) analysis, histological finding and magnetic resonance image (MRI) appearance. We report an ADEM case with unusual clinical presentations of predominant psychiatric symptoms, and relatively long disease course. Initially, we were not able to distinguish it from single episode MS. By means of sequential MR images followed up 2 years and spectroscopy studies, and the dramatic clinical improvement after corticosteroid therapy, ADEM was diagnosed as the disease entity of this patient. In this case report we will present the MR findings of this patient and discuss the differentiation between the ADEM and MS.

Image evaluation of suprazygomatic masticator space lesions

In order to understand lesions involving the suprazygomatic masticator space (SZMS) demonstrated on computered tomography (CT) or magnetic resonance (MR) images, we collected 45 cases of lesions in SZMS. There were hematomas in 26 cases, tumors in 16 cases, and abscesses in 3 cases. The location of these lesions in compartments of the SZMS and adjacent structures was analyzed. Most commonly hematoma was found in the deep loose connective tissue (80.8%), followed by the superficial dense connective tissue (61.5%). Only 2 SZMS hematoma involved the superficial fat pad. Five patients had air accumulation in the SZMS, and all were in the deep fat pad and with maxillary sinus fracture. Of the sixteen cases which were tumors, 12 were extended from adjacent structures, and four were primary tumor. In cases of tumor, compartments of SZMS involved most frequently were temporal muscles (15 of 16 cases), followed by deep fat pad (8 of 16 cases). The connective tissue layer of SZMS is a communication pathway for superficial spread of infection, hematoma, or tumor invasion to or from the scalp and face. Compartments of deep fat pad and temporal muscle are also pathways for the spread of disease to or from the face, intracranium and orbit. The primary tumors in infratemporal fossa and SZMS are rare. Malignant tumors in SZMS usually come from surrounding spaces.

Oxygen- and growth rate-dependent regulation of Escherichia coli fumarase (FumA, FumB, and FumC) activity

Escherichia coli contains three biochemically distinct fumarases which catalyze the interconversion of fumarate to L-malate in the tricarboxylic acid cycle. Batch culture studies indicated that fumarase activities varied according to carbon substrate and cell doubling time. Growth rate control of fumarase activities in the wild type and mutants was demonstrated in continuous culture; FumA and FumC activities were induced four- to fivefold when the cell growth rate (k) was lowered from 1.2/h to 0.24/h at 1 and 21% O(2), respectively. There was a twofold induction of FumA and FumC activities when acetate was utilized instead of glucose as the sole carbon source. However, these fumarase activities were still shown to be under growth rate control. Thus, the activity of the fumarases is regulated by the cell growth rate and carbon source utilization independently. Further examination of FumA and FumC activities in a cya mutant suggested that growth rate control of FumA and FumC activities is cyclic AMP dependent. Although the total fumarase activity increased under aerobic conditions, the individual fumarase activities varied under different oxygen levels. While FumB activity was maximal during anaerobic growth (k = 0.6/h), FumA was the major enzyme under anaerobic cell growth, and the maximum activity was achieved when oxygen was elevated to 1 to 2%. Further increase in the oxygen level caused inactivation of FumA and FumB activities by the high oxidized state, but FumC activity increased simultaneously when the oxygen level was higher than 4%. The same regulation of the activities of fumarases in response to different oxygen levels was also found in mutants. Therefore, synthesis of the three fumarase enzymes is controlled in a hierarchical fashion depending on the environmental oxygen that the cell encounters.

MR perfusion studies of brain for patients with unilateral carotid stenosis or occlusion: evaluation of maps of "time to peak" and "percentage of baseline at peak"

Maps of "time to peak" (TTP) and "percentage of baseline at peak" (PBP) were compared with maps of conventional brain perfusion parameters, namely, mean transit time (MTT) and relative cerebral blood volume (rCBV). We performed MR perfusion studies in 11 patients. All of them had occlusion or high-grade stenosis of the unilateral carotid artery. Three areas of old infarct, 4 areas of new infarct, and 10 areas of brain without infarct were evaluated specifically. In all these cases, the TTP maps appeared similar to the MTT maps. They showed increases, normal values, or decreases at the same time in all areas evaluated. Most areas of abnormally decreased CBV had increased signal in PBP maps. In conclusion, the TTP map provided the same qualitative information as MTT. PBP seemed correlated inversely to CBV and was less sensitive in demonstrating abnormality.

Liquid products from oxidative thermal treatment of oil sludge with different oxygen concentrations of air

Oxidative thermal treatment of oil sludge with different oxygen concentrations of air by using a dynamic thermogravimetric (TG) reaction system is investigated. The experimental conditions employed are: gas flow rate of 50 cm3/min (value at 298 K) for 300 mg dry waste, a constant heating rate of 5.2 K/min, the oxygen concentrations in air of 1.09, 8.62 and 20.95 vol. % O2, and the temperature (T) range of 378-873 K. From the experimental results, the residual mass fractions (M) are about 78.95, 28.49, 8.77 and 4.13 wt. % at the oxidative T of 563, 713, 763 and 873 K for the case with 20.95 vol. % O2, respectively. The values of M with 8.62 and 1.09 vol. % O2 at T of 873 K are 4.87 and 9.44 wt. %, respectively. The distillation characteristics of the oil portion of liquid products (condensates of gas at 298 K) from the oxidative thermal treatment of oil sludge with 20.95 vol. % O2 at T of 378-873 K is close to those of commercial gasoline. Nevertheless, the liquid product contains a large amount of water. The distillation characteristics of the oil portions of liquid products with 8.62 and 1.09 vol. % O2 at T of 378-873 K are close to those of diesel and fuel oils, respectively. The oil quality with 8.62 vol. % O2 is better than that with 1.09 vol. % O2. However, the liquid product with 8.62 vol. % O2 still contains a large amount of water; nonetheless, that with 1.09 vol. % O2 is with negligible water. Compared with the oil product of nitrogen pyrolysis, the oil quality with 1.09 vol. % O2 is better. Certainly, low oxygen conditions (i.e. 1.09 vol. % O2) not only accelerate the thermal reaction of oil sludge, but also at the same time avoid or reduce the production of water. Further, from the analysis of benzene (B), ethylbenzene (E), toluene (T) and iso-xylene (X) concentrations of the oil portion of liquid products, the BETX concentrations of oil with 20.95 vol. % O2 are higher than those with 8.62 and 1.09 vol. % O2. The yields of liquid products with 20.95, 8.62 and 1.09 vol. % O2 at T of 378-873 K are 31.96, 34.42 and 37.3 wt. %, respectively. From the experimental results, the improvement effects of oxygen on the qualities of the oil portion of liquid products are obvious. The above technique not only formats good quality gasoline and diesel oils but also reduces large amount of oil sludge. If the oil exists with water, it may be obtained by further separation or collected by fractional condensation.

Cluster of genes encoding the major egg envelope protein of zebrafish

The proteins of fish egg envelopes are encoded by genes that are closely related to the genes for human zona pellucida proteins. A cluster of three genes coding for an egg envelope protein was isolated from the zebrafish, Danio rerio. The three genes, zp2a, zp2b, and zp2c, are located within an 11 kb region and are each comprised of eight exons spanning 1.85 kb. The exon-intron structures of the genes are nearly identical; however, their deduced amino acid sequences diverge at exon 7 (zp2b and zp2c from zp2a) and exon 8 (zp2c from zp2b). Exons 2-7 have a structural organization similar to exons in the carboxy-terminal half of the human zona pellucida ZP1, ZP2, and ZPB genes, suggesting they arose from a common ancestral gene. Sequence comparisons indicate that the deduced zebrafish proteins are most closely related to human ZPB. Zebrafish mRNAs coding for each of the three ZP2 variants have been found either as full-length cDNAs or expressed sequence tags. Distinct from the wf(female) gene of winter flounder which we first reported (Lyons et al., 1993: J Biol Chem 268:21351-21358), expression of the zebrafish zp2 genes was found to be ovary-specific, instead of liver-specific, and the promoter regions of zp2a and zp2b, while different, both contained E-box sequences (CANNTG) that have been demonstrated to be essential for coordination of zona pellucida gene expression in mammalian oocytes. Mixed peptide sequence analysis was used to identify the major polypeptide component of isolated zebrafish egg envelopes as the zp2 gene product.

Thermal pyrolysis characteristics of polymer flocculated waste activated sludge

Polyelectrolyte conditioning is a common practice in wastewater management. This paper experimentally elucidated the thermal pyrolysis characteristics of waste activated sludge at a temperature range of 300-900 K (27-627 degrees C) using thermogravimetric analysis (TGA) in inert atmosphere, with especial attention on the effect of polyelectrolyte flocculation (using cationic polyacrylamide). On the pyrolysis rate vs temperature plot two maxima were noted. At the heating rate of 8 degrees C/min, polyelectrolyte does not influence the pyrolysis process. As higher heating rates (14 and 20 degrees C/min), on the other hand, flocculation to charge neutralization point would enhance the rate of thermal pyrolysis. A simple two parallel-reaction kinetic model is applied to interpret the experimental data. Possible roles of flocculant on sludge pyrolysis are discussed on the basis of change in sludge structures and the hindrance of surface reactions of sludge particles.

Struma ovarii mimicking a benign multicystic ovarian tumor: MR imaging in one case

Struma ovarii is a rare form of mature teratoma of the ovary. A case of struma ovarii is presented with magnetic resonance (MR) imaging and pathologic findings. MR imaging showed a multiloculated cystic adnexal mass with well-defined margin and septum. Internal cystic spaces presented homogeneous signal intensity of fluid content in both T1-weighted and T2-weighted images. Subtle contrast enhancement was depicted in internal septi. Imaging features were indistinguishable from benign multicystic ovarian tumor, and different from the reported cases in the literature.

Temporally distinct and ligand-specific recruitment of nuclear receptor-interacting peptides and cofactors to subnuclear domains containing the estrogen receptor

Ligand binding to estrogen receptor (ER) is presumed to regulate the type and timing of ER interactions with different cofactors. Using fluorescence microscopy in living cells, we characterized the recruitment of five different green fluorescent protein (GFP)-labeled ER-interacting peptides to the distinct subnuclear compartment occupied by blue fluorescent protein (BFP)-labeled ER alpha. Different ligands promoted the recruitment of different peptides. One peptide was recruited in response to estradiol (E2), tamoxifen, raloxifene, or ICI 182,780 incubation whereas other peptides were recruited specifically by E2 or tamoxifen. Peptides containing different sequences surrounding the ER-interacting motif LXXLL were recruited with different time courses after E2 addition. Complex temporal kinetics also were observed for recruitment of the full-length, ER cofactor glucocorticoid receptor-interacting protein 1 (GRIP1); rapid, E2-dependent recruitment of GRIP1 was blocked by mutation of the GRIP1 LXXLL motifs to LXXAA whereas slower E2 recruitment persisted for the GRIP1 LXXAA mutant. This suggested the presence of multiple, temporally distinct GRIP 1 recruitment mechanisms. E2 recruitment of GRIP1 and LXXLL peptides was blocked by coincubation with excess ICI 182,780. In contrast, preformed E2/ER/GRIP1 and E2/ER/LXXLL complexes were resistant to subsequent ICI 182,780 addition whereas ICI 182,780 dispersed preformed complexes containing the GRIP1 LXXAA mutant. This suggested that E2-induced LXXLL binding altered subsequent ligand/ER interactions. Thus, alternative, ligand-selective recruitment and dissociation mechanisms with distinct temporal sequences are available for ER alpha action in vivo.

Adsorption Equilibrium of Polyethylene Glycol in the Copper Electroplating Solution on Activated Carbon

Polyethylene glycol (PEG) used as a brightening and stabilization agent at the concentration of 30 mg dm(-3) is a major organic additive in the copper electroplating solution. Activated carbon, Calgon Filtrasob 400, is used as the adsorbent to remove the PEG from the used electroplating solution in order to broaden the appeal of recycling it. The equilibrium of adsorption is attained within 14 days. The effect of the temperature on the amount of PEG adsorbed on the activated carbon is insignificant for the temperatures ranged from 288 to 313 K. The adsorption isotherm of PEG conforms to the Langmuir isotherm, q(e)=Q(L)K(L)C(e)/(1+K(L)C(e)), with a high correlation coefficient of 0.9979. The large values of the monolayer adsorption capacity, Q(L), of 303 mg g(-1) and the equilibrium constant, K(L), of 0.273 dm(3) mg(-1) show a great adsorption potential of PEG on the activated carbon. A high removal efficiency would be expected at such a low original concentration of PEG. From the results mentioned above, it is feasible to use activated carbon for removing PEG from the electroplating solution, thereby achieving the appeal of recycling. Copyright 2000 Academic Press.

Effects of Burn-off and Activation Temperature on Preparation of Activated Carbon from Corn Cob Agrowaste by CO(2) and Steam

Previous studies have successfully demonstrated that corn cob is a suitable precursor for production of good activated carbon by chemical activation. However, respond to the need for cleaner production, this study focuses on the physical activation by gasifying agents such as CO(2) and steam. The activation temperatures under investigation are 1073 and 1173 K. Within the limit of 50 wt% burn-off, experimental results reveal that the BET surface area, pore volume, and average pore diameter of the resulting activated carbon generally increase with the extent of burn-off in both gasifying agents and at both temperatures. The higher activation temperature can overcome the drawbacks of a longer period of activation required to attain larger surface area and can offer higher potential to produce activated carbon of greater adsorption capacity from agriculture wastes such as corn cobs. Additionally, the BET surface areas of properly prepared activated carbons can satisfy commercial requirements, when compared with commercial activated carbon. The BET surface areas of the activated carbons after about 71 and 59 wt% burn-off of CO(2) and steam activations at 1173 K are 1705 and 1315 m(2)/g, respectively, indicating high adsorption capacities. Thus, it is feasible to produce high-quality microporous activated carbon from corn cob agrowaste using N(2) carbonization followed by physical activation with CO(2) or steam. Copyright 2000 Academic Press.

Lack of association between angiotensin I-converting enzyme gene deletion polymorphism and cerebrovascular disease in Taiwanese

BACKGROUND AND PURPOSE

Angiotensin I-converting enzyme (ACE) gene deletion polymorphism (D) has recently been suggested as a significant risk factor for cerebrovascular disease in studies involving Japanese and white populations. We investigated the role of ACE D polymorphism in the pathogenesis of cerebrovascular disease in Taiwanese.

METHODS

To examine the association of ACE genotype and allele frequency with cerebrovascular disease, we conducted a study of 306 stroke patients and 300 control subjects matched by age and sex.

RESULTS

Although the frequencies of both the homozygous deletion (DD) genotype and the D allele were greater in stroke patients than in control subjects, these differences were not significant. Further comparison of the frequencies of the DD genotype and the D allele in the three stroke subgroups (intracerebral hemorrhage, probable large-vessel disease, and probable small-vessel lacunar infarction) with the control group revealed no significant associations. Moreover, ACE gene polymorphism was not significantly associated with age of onset of stroke. Stepwise logistic regression analysis of the presence of the D allele and data on risk factors confirmed the lack of significant association between ACE deletion polymorphism and cerebrovascular disease. Moreover, no association was identified between ACE genotypes and any of the relative risk factors for cerebral infarction or severity of carotid atherosclerosis.

CONCLUSIONS

Our results suggest that deletion polymorphism of the ACE gene is not associated with the pathogenesis of cerebrovascular disease in Taiwanese.