Rapid urease tests lack sensitivity in Helicobacter pylori diagnosis when peptic ulcer disease presents with bleeding

OBJECTIVE

The eradication of Helicobacter pylori (H. pylori) in patients with bleeding peptic ulcer disease (PUD) decreases the rate of ulcer rebleeding. Although all methods for H. pylori diagnosis have been extensively evaluated in uncomplicated PUD the efficacy of the commonly used rapid urease test (RUT) has not been established in patients with bleeding peptic ulcer disease. The aim of this study was to evaluate the efficacy of the RUT (CLOtest) in patients with bleeding duodenal ulcers (DUs).

METHODS

Consecutive patients with symptoms of upper GI tract hemorrhage and a DU at the time of endoscopy were evaluated. The presence of H. pylori infection was determined by RUT, microbiology, and histology. Consecutive patients with uncomplicated DUs were similarly evaluated. The prevalence of H. pylori as determined by the RUT alone was compared to that determined by a combination of all tests in both patient groups.

RESULTS

Fifty-five patients with bleeding DUs and 69 with nonbleeding DUs were evaluated. The prevalence of H. pylori in patients presenting with bleeding was 72.7% (95% confidence interval [CI] 61.0-84.5%) and lower than the prevalence rate of 92.8% (95% CI 86.6-98.8%) in patients with uncomplicated PUD (p < 0.05). The prevalence of H. pylori in the bleeding DU group as determined by RUT alone (54.5%) was less than that determined by a combination of all tests (73%) with a false-negative rate of 10 of 40 (25%; 95% CI 11.6-38.4%) (p < 0.05). This false-negative rate was significantly greater than that observed in the group presenting with dyspepsia (1 of 64 [1.6%; 95% CI 0-4.6%]) (p < 0.01).

CONCLUSIONS

The prevalence of H. pylori is lower in patients with bleeding DUs when compared to patients with uncomplicated DUs. In addition, the sensitivity and negative predictive value of the RUT is lower in patients presenting with bleeding, and other methods of H. pylori diagnosis should be used in this patient group.

Increased numbers of both airway basophils and mast cells in sputum after allergen inhalation challenge of atopic asthmatics

Mast cells and basophils are metachromatic cells that participate in allergic inflammation. Allergen challenge to the airways of atopic asthmatic individuals increases levels of metachromatic cells, which may reflect an increase in mast cells, basophils, or both. We conducted a study to characterize the kinetics of basophil and mast cell recruitment to the airways of atopic asthmatic subjects after allergen inhalation challenge, using monoclonal antibodies specific for each type of cell. Of 19 subjects, 14 developed both early- and late-phase asthmatic responses (dual responders [DRs]), whereas five developed only early asthmatic responses (early responders [ERs]) after allergen inhalation. There was a significant increase in the number of sputum eosinophils (p < 0.002) and basophils (p < 0.002) at 7 h and 24 h after challenge in both ERs and DRs. There was also a significant increase in the number of activated eosinophils (p = 0. 00002) and mast cells (p = 0.009) in sputum at 7 h and 24 h after challenge in DRs, but not in ERs (p > 0.4). DRs had a significantly higher number of allergen-induced sputum basophils than did ERs (p < 0.01), and sputum basophils correlated significantly with airway hyperresponsiveness (AHR) to methacholine at 24 h after challenge (r = 0.66, p = 0.002). DRs tended to have higher allergen-induced basophil levels than did ERs, which may contribute to the observed AHR.

Combined analysis of germline polymorphisms of p53, GSTM1, GSTT1, CYP1A1, and CYP2E1: relation to the incidence rate of cervical carcinoma

BACKGROUND

The authors established the genotype frequencies of cytochrome P450 (CYP1A1/MspI, CYP2E1/PstI, and CYP2E1/DraI), glutathione-S-transferase (GSTM1 and GSTT1), and p53 (exon 4/AcclI and intron 3/16-base pair duplication) gene polymorphisms in cervical carcinoma patients and controls and evaluated the association between the specific genotype or genotype combinations of these polymorphisms and the risk of cervical carcinoma.

METHODS

In this case-control study, the genotypes of 181 human papillomavirus (HPV)-16 or HPV-18 positive cervical carcinoma patients and 1-to-1 age-matched controls were determined using a polymerase chain reaction-based technique.

RESULTS

Among these polymorphisms, the individuals carrying arginine/proline genotypes of p53 showed a 9.5-fold increase of cervical carcinoma risk (95% confidence interval [CI], 4.9-18.6) compared with those individuals carrying arginine/arginine genotypes. The frequency of overall GSTT1 null genotypes also was significantly higher in cervical carcinoma patients compared with that of GSTT1 positive genotypes (P = 0.003; odds ratio [OR] = 1.9; 95% CI, 1.2-2.9). The genotype combination of p53 and GST played a more important role in describing the relative risk of cervical carcinoma. The individuals carrying both the arginine/proline genotype of p53 and the null genotype of GSTT1 showed a 3.5-fold increase of cervical carcinoma risk (95% CI, 1.8-7.1) compared with those individuals carrying both the arginine/arginine genotype of p53 and the GSTT1 positive genotype. In the patients who were stratified into the two age groups, the null genotypes of GSTT1 (69.1% vs. 45.5%; P = 0.016) and GSTM1 (61.8% vs. 40.0%; P = 0.028) in cervical carcinoma were significantly overrepresented in the younger age subgroup (age 40 years or younger) compared with those of controls. Especially in this age group, the individuals carrying both null genotypes of GSTT1 and GSTM1 showed a 17.8-fold increase of cervical carcinoma risk (95% CI, 2.2-141.0) compared with the individuals carrying both positive genotypes of GSTT1 and GSTM1.

CONCLUSIONS

The results of the current study suggested that the arginine/proline genotype of p53, independently or in conjunction with the GSTT1 null genotype, could affect the genetic susceptibility for cervical carcinoma, and HPV positive women carrying both null genotypes of GSTT1 and GSTM1 have an increased risk of cervical carcinoma developing before age 40 years.

Abundance of cyclin B1 regulates gamma-radiation-induced apoptosis

gamma-Radiation is a potent inducer of apoptosis. There are multiple pathways regulating DNA damage-induced apoptosis, and we set out to identify novel mechanisms regulating gamma-radiation-induced apoptosis in hematopoietic cells. In this report, we present data implicating the cyclin B1 protein as a regulator of apoptotic fate following DNA damage. Cyclin B1 is the regulatory subunit of the cdc2 serine/threonine kinase, and accumulation of cyclin B1 in late G2 phase of the cell cycle is a prerequisite for mitotic initiation in mammalian cells. We find that abundance of the cyclin B1 protein rapidly increases in several mouse and human hematopoietic cells (Ramos, DP16, HL60, thymocytes) undergoing gamma-radiation-induced apoptosis. Cyclin B1 accumulation occurs in all phases of the cell cycle. Antisense inhibition of cyclin B1 accumulation decreases apoptosis, and ectopic cyclin B1 expression is sufficient to induce apoptosis. These observations are consistent with the idea that cyclin B1 is both necessary and sufficient for gamma-radiation-induced apoptosis. (Blood. 2000;95:2645-2650)

CT-guided celiac plexus block for intractable abdominal pain

Treatment of intractable abdominal pain due to inoperable intraabdominal malignancy is important, and the ineffectiveness of pharmacological agents has led many investigators to recommend chemical neurolysis of the celiac ganglions as a treatment. The author describes the technique and results of celiac plexus neurolysis under CT-guidance with various approach routes, including anterior, posterior and transaortic routes. Twenty-eight patients, ranging in age from 36 to 82 years, have been treated with this procedure. All had inoperable or recurred intraabdominal malignancies and suffered from intractable upper abdominal pain and/or back pain. The author performed the procedure using absolute alcohol by an anterior approach (n=18), posterior approach (n=6) and transaortic approach (n=4). Pain was rated according to a visual analog scale before and after the procedure to gauge treatment success. No major complications occurred. Mild hypotension occurred in five patients (18%) and transient diarrhea in six patients (21%). Twenty-one (75%) of the 28 patients had some relief of pain and 17 of these patients (61%) had good relief of pain after the procedure. The results support that CT-guided celiac plexus block with alcohol is a safe and effective means of pain control in patients with intraabdominal malignancy.

MR characteristics of progressive massive fibrosis

This study was performed to evaluate the static and dynamic magnetic resonance imaging (MRI) contrast enhancement pattern of progressive massive fibrosis (PMF) in coal workers' pneumoconiosis. Eighteen lesions in 12 patients were evaluated using a 1.5-T MR unit. T1-weighted FLASH images were obtained before and 0.5, 1, 2, 3, 4, 5, 7.5, 10, 12.5, and 15 minutes after injection of gadolinium diethylenetriamine penta-acetic acid (Gd-DTPA; 0.1 mmol/kg). Imaging findings, the contrast enhancing pattern, enhancement time curve, and the contrast uptake equivalent (CE; mmol/L) were evaluated. On T1-weighted images, 14 lesions showed high signal intensity, and four showed low signal intensity. On T2-weighted images, all lesions were of low signal intensity and were indistinguishable from aerated lung parenchyma. After contrast infusion, all lesions except two enhanced markedly. The time enhancement curve showed a marked, gradual increase in signal intensity up to 3 minutes, a subtle increase in signal intensity up to 7.5 minutes, and then a plateau until 15 minutes after Gd-DTPA injection. Characteristic MR findings of PMF in coal workers' pneumoconiosis include T1 high signal intensity, T2 low signal intensity, and marked postinfusion enhancement. The time enhancement curve shows a marked, gradual increase of signal intensity up to 3 minutes and plateau up to 15 minutes.

Helicobacter pylori eradication therapy: a discrepancy between current guidelines and clinical practice

BACKGROUND

Consensus guidelines recommend that patients with peptic ulcer disease, and other causes of dyspepsia, should be treated with Helicobacter pylori eradication regimens. However, it has not been firmly established whether physicians have adapted their practice accordingly.

OBJECTIVES

(1) To establish the proportion of ulcer-healing prescriptions that H. pylori eradication regimens accounted for, (2) to evaluate the composition of the eradication regimens used, and (3) to compare the prescribing patterns of specialist and primary care practitioners.

METHODS

Seven community pharmacy practices were identified, and all prescriptions for individual acid-suppressing agents and eradication regimens were prospectively evaluated over an initial one-month period. Prospective documentation and evaluation of eradication regimens only was then continued for a further three-month period.

RESULTS

The prescriptions for 585 patients were evaluated. Proton-pump inhibitors and H2-receptor antagonists accounted for 261 (44.5%) and 307 (52.5%) of prescriptions respectively. H. pylori eradication therapy was prescribed for 17 (2.9%) patients in this initial period. Sixty-six eradication regimens were evaluated over four months: 48/66 (73%) of these were initiated by primary care practitioners and 18/66 (27%) by specialists. Thirteen different combinations of antibiotics and acid-suppressing agents were identified - many of undocumented efficacy. Dual, triple and quadruple regimens accounted for 15 (23%), 48 (72.5%) and 3 (4.5%) of patient prescriptions respectively.

CONCLUSION

H. pylori eradication therapy currently accounts for a very small proportion of ulcer-healing medication in clinical practice. Most eradication regimens are initiated by primary care practitioners. In comparison with specialist practices, prescriptions from this source are more likely to be of undocumented efficacy.

Weber-Christian disease presenting with proptosis: a case report

Weber-Christian disease (WCD) is a rare inflammatory disease of adipose tissue, which is characterized by painful cutaneous nodules and constitutional symptoms. Although any area of the body containing fat can be affected by WCD, the involvement of retrobulbar fat is uncommon and proptosis is a rare presenting manifestation. We report a case who presented with proptosis of the right eye which is accompanied by painful subcutaneous nodules, high fever and myalgia. Biopsies of retrobulbar tissue and suprapubic nodule showed lobular panniculitis with mixed cellular infiltration, mainly composed of histiocytes and lymphocytes. He responded well to high-dose glucocorticoid.

AAC-11 overexpression induces invasion and protects cervical cancer cells from apoptosis

To identify the genes involved in cervical carcinogenesis, we applied the mRNA differential display (DD) method to analyze normal cervical tissue, cervical cancer, metastatic lymph node, and cervical cancer cell line. We cloned a 491-bp cDNA fragment, CC231, which was present in metastatic tissue and cervical cancer cell line, but absent in normal cervical and cervical cancer tissues. The 491 bp cDNA fragment has 98% homology to the previously published sequence, AAC-11 (antiapoptosis clone 11). The levels of AAC-11 mRNA expressions in nine normal cervical and nine primary cervical cancer tissues were low. Its expression was higher in three metastatic tissues and five cervical cancer cell lines (HeLa, CaSki, SiHa, CUMC-3, and CUMC-6). Invasion of matrigel and adhesion to laminin by AAC-11 transfected CUMC-6 cells were increased by approximately 2-fold and 4-fold, respectively. Northern blot analysis showed that matrix metalloproteinase (MMP)-2 and membrane type 1 MMP (MT1-MMP) genes were found to be expressed in high levels in AAC-11-transfected cancer cells. But MMP-2 and MT1-MMP were not expressed in cells transfected with vector alone or wild-type cells. AAC-11-transfected cells expressed an elevated level of MMP-2 protein as assessed by immunoblotting. On the contrary, tissue inhibitor of MMP (TIMP-2) expression was detectable in cells transfected with vector alone or wild-type cells, respectively. Its expression was undetectable in AAC-11 transfected cells. In cervical cancer cells transfected with AAC-11, the expression of beta-catenin was up-regulated. These suggest that overexpressions of MMP-2 and MT1-MMP, loss of TIMP-2 expression, and up-regulation of beta-catenin by AAC-11 transfection may contribute to the development of cervical cancer invasion. AAC-11 gene transfection increased cervical cancer cell colonization. The effect of AAC-11 on cultured cervical cancer cells was associated with antiapoptotic process. Approximately 50% of the AAC-11 transfected cells in serum-free medium died after 2 weeks, compared to 1 week for vector alone or wild-type cells. These results suggest that AAC-11 may serve as a candidate metastasis-related and apoptosis-inhibiting gene in human cervical cancer.

Antioxidant and anti-tumor promoting activities of the methanol extract of heat-processed ginseng

Heat treatment of Panax ginseng C.A. Meyer at a temperature higher than that applied to the conventional preparation of red ginseng yielded a mixture of saponins with potent antioxidative properties. Thus, the methanol extract of heat-processed neoginseng (designated as 'NGMe') attenuated lipid peroxidation in rat brain homogenates induced by ferric ion or ferric ion plus ascorbic acid. Furthermore, the extract protected against strand scission in phiX174 supercoiled DNA induced by UV photolysis of H2O2, and was also capable of scavenging superoxide generated by xanthine-xanthine oxidase or by 12-O-tetradecanoylphorbol-13-acetate (TPA) in differentiated human promyelocytic leukemia (HL-60) cells. Topical application of NGMe onto shaven backs of female ICR mice 10 min prior to TPA, significantly ameliorated skin papillomagenesis initiated by 7,12-dimethylbenz[a]anthracene. Moreover, TPA-induced enhancement of epidermal ornithine decarboxylase (ODC) activity and ODC mRNA expression was abolished by a topical dose (0.68 mg) of NGMe. Likewise, TPA-induced production of tumor necrosis factor- in mouse skin was inhibited by NGMe pretreatment.

A simple and rapid method for cloning insect vitellogenin cDNAs

We describe a simple and rapid method for cloning insect vitellogenin (Vg) cDNAs. The method relies on the facts that insect Vg amino acid sequences can be aligned confidently along their entire lengths and that a short, highly conserved GL/ICG motif and up to nine cysteine residues that follow at conserved locations are present near the C-termini. An adaptor-ligated double-strand cDNA library is constructed from poly(A)+ RNA prepared from vitellogenic female fat body tissues using a commercial kit, and subjected to PCR with each of the degenerate nucleotide sequences for the GL/ICG motif and the adaptor sequence as primers. The PCR products (0.7-0.9 kb, representing the 3' portion) are cloned, the nucleotide sequences are determined, and the deduced amino acid sequences are aligned with the known insect Vg sequences starting from the GL/ICG motif. Gene-specific primers corresponding to the sequences near the 5'-termini of the initial clones and the adaptor sequence are employed to obtain the remaining 5' portion of the Vg cDNAs. The method was successfully applied to the bean bug Plautia stali (Heteroptera), revealing three Vg genes.

Eigenmode analysis of arbitrarily shaped two-dimensional cavities by the method of point-matching

In the proposed method, as in the boundary element method (BEM), a field problem is solved on its boundary along which nodes are distributed. The distinct feature of the proposed method is related to the fact that no interpolation functions between the nodes are required, so that the basic collocation method is employed to satisfy a given boundary condition. This approach reduces a large amount of numerical calculation induced due to the interpolation functions. Unlike the method of auxiliary sources (MAS), in the proposed method only the regular functions that have finite functional values everywhere including the origins are employed as basis functions. As a result, the proposed method does not need the auxiliary surface, the construction of which is a troublesome work because its form, dimension, shifting, etc. strongly influence the accuracy of the MAS. The eigenvalues calculated by the proposed method rapidly converge to the exact values thanks to the simplicity of the method. Moreover, the method gives mode shapes successfully without using the interpolation functions between the nodes. The efficiency and accuracy of the method are verified through several applications.

Correlation effect in activity measurement of 59Fe

Correlation effects due to the cascade transition of gamma-rays with gates on the relevant peaks have been studied in activity measurement of 59Fe using the bi-dimensional coincidence counting method. Extrapolation curves were obtained at three gamma gates of 1099.2 keV, 1291.6 keV, and that covering both photo-peaks by a computer discrimination method. Of these extrapolation curves, only that obtained at (950-1350) keV gamma gate shows a linear variation, but those of two single gamma gates are not linearly varied in the high efficiency region. This nonlinearity obtained at the gamma gate of 1099.2 keV photo-peak was caused by the correlation effects due to 1-3 coincidence relation via unobserved 192 keV gamma-ray transitions.

Artificial reproduction in a hymenopteran insect, Athalia rosae, using eggs matured with heterospecific yolk proteins and fertilized with cryopreserved sperm

Previtellogenic ovaries of Athalia rosae (Hymenoptera, Symphyta, Tenthredinidae) were transplanted into the adult female abdominal hemocoel of Athalia infumata (Symphyta, Tenthredinidae), Arge nigrinodosa (Symphyta, Argidae), and Pimpla nipponica (Apocrita, Ichneumonidae). The donor oocytes accumulated heterospecific yolk proteins and matured in the A. infumata host. On average, six mature oocytes were obtained per transplanted ovary. In contrast, the donor oocytes accumulated a limited amount of yolk but did not mature in the Ar. nigrinodosa host and did not even accumulate yolk in the P. nipponica host. The eggs that matured in the A. infumata host were injected with cryopreserved A. rosae sperm that had been taken from adult male seminal vesicles and stored at -80 degrees C. Fertilization, as confirmed by the use of visible marker mutations, was achieved and a fraction of the injected eggs developed into fertile female adults.

Development of a three-dimensional data acquisition method for standardization of beta-emitting nuclides

We have developed a three-dimensional data-acquisition system with which pulse heights from an array of detectors can be multi-scaled with dwell times as short as 31 ns. The main part of the system consists of three ADCs of SAR (Successive Approximation Register) type, a 32 MHz oscillation clock and DRAM (Dynamic Random Access Memory) of 192 Mbyte capacity. The clock time is determined by count the clock pulse generated by 28 bits synchronous counter. Both the pulse height and the time information are stored at an array of DRAM, of 40-bits width, 12-bits for pulse height and 28-bits for clock time. The technique is particularly suitable for experiments such as both double and triple coincidence distributions are required. Virtues of the method are demonstrated by measuring the activity of 14C with a 3-PM liquid scintillation counting system. The computer discrimination together with the MCTS (multi-channel time scaling) technique is applied for efficiency variation method in the analysis.

Amyloid-beta injection in rat amygdala alters tau protein but not mRNA expression

Previously we demonstrated local and distant changes in tau protein immunoreactivity reminiscent of those seen in Alzheimer's disease (AD) following a unilateral injection of amyloid-beta (Abeta)(25-35) into the rat amygdala. To explore the relevance of these findings to AD, we compared the effects of Abeta(1-42) to those of Abeta(25-35). Injections of both Abeta(1-42) and Abeta(25-35) into rat amygdala resulted in increased tau-2 immunolabeling in neurons. To determine whether these alterations were due to changes in the expression of tau, we measured tau protein expression by Western blotting and tau mRNA isoform expression by the reverse transcription-polymerase chain reaction in the amygdala, hippocampus, and cerebellum following a unilateral injection of Abeta(25-35) or vehicle into the amygdala. The levels of tau proteins were increased bilaterally in the amygdala of Abeta(25-35)- compared to vehicle-treated animals 8 and 16 days following treatment. The molecular weights of tau proteins were decreased in the Abeta(25-35)-treated (59-69 kDa) compared to the vehicle-treated (67-72 kDa) animals 8 days following treatment. There were no changes in tau mRNA expression in any brain region examined. In this model, just as in AD, there is an increase in tau protein levels without a change in tau mRNA expression, suggesting that Abeta peptides may influence tau protein stability in both the rat and the human brain.

Neuroprotection due to irrigation during bipolar cautery

OBJECTIVE

To test whether irrigation during bipolar cautery confers thermoprotection from neuronal injury.

DESIGN

A rat animal model (15 rats for each treatment group) was used to test the thermoprotective effects of irrigation during bipolar cautery. In this model, the sciatic nerve was exposed, and a 1-second stimulus was applied using bipolar cautery forceps at 40 or 20 W placed directly on the nerve in the presence or absence of simultaneous irrigation. The effects of cautery were determined on the basis of clinical gait analysis by means of the Sciatic Functional Index, temperature response, and neuropathological findings.

RESULTS

The degree of paresis was reduced with irrigation. Neuropathological examination of the sciatic nerve after cautery showed significant axonal loss (more small than large fibers) with concomitant demyelination, which was partially inhibited by irrigation (chi2; P = .04). The mechanism of thermoprotection by irrigation was not the result of a reduction in the temperature spike that followed cautery, but resulted from a reduced temperature response during the 15 seconds that followed 40- or 20-W stimulation with bipolar cautery.

CONCLUSIONS

Simultaneous irrigation and bipolar cautery enhance temperature recovery to basal levels and protect the peripheral nerve from the effects of cautery.

An improved optical technique for monitoring plant cell concentration

 An improved optical method was developed to determine cell weight concentrations using a micro-plate reader. Light absorbance was measured by a vertical light beam, which can minimize the cell settling effect found in traditional optical measurements with a horizontal light beam. The use of well plates not only requires very small sample sizes, but also handles a large number of samples at the same time. Absorbance measurements were linearly related to cell weight over the full range of batch culture growth.

Vitellogenin of the cicada Graptopsaltria nigrofuscata (Homoptera): analysis of its primary structure

We cloned and sequenced the cDNA of vitellogenin (Vg) from the cicada Graptopsaltria nigrofuscata (Homoptera). The deduced amino acid sequence of 1987 residues (including 16 residues for a putative signal peptide) was obtained. The pro-Vg was cleaved into two subunits between residues 379 and 380 following a consensus RXXR cleavage site sequence, secreted as S-Vg (apparent molecular weight 43 kDa) and L-Vg (200 kDa), sequestered, and stored in the egg as two vitellins (Vns), S-Vn and L-Vn, with similar respective molecular weights. There was a single long serine-rich stretch closely following the cleavage site. The entire amino acid sequences of the Vgs from the eight insects so far reported could be aligned confidently. The presence of subdomains I-V (areas of relatively high amino acid conservation) and of 10 cysteines at conserved locations at the C-terminus, noted previously among insect Vgs, were confirmed. Antisera raised against G. nigrofuscata S- and L-Vn cross-reacted with the S- and L-Vg/Vn, respectively, of all three other cicada species examined. Another major egg protein (170 kDa) unrelated to Vg/Vn, was also detected in all species examined.

Solitary necrotic nodules of the liver mimicking hepatic metastasis: report of two cases

We present two cases of solitary necrotic nodules of the liver which on radiologic images mimicked hepatic metastasis. Solitary necrotic nodule of the liver is a rare but benign entity which histopathologically consists of an outer fibrotic capsule with inflammatory cells and a central core of amorphous necrotic material. The lesion was seen on contrast-enhanced CT as an ovoid-shaped hypoattenuating nodule; on CT during hepatic arteriography as enhancing nodule; on intraoperative US as a target-appearing hypoechoic nodule; on T2WI as a hyperintensity nodule, and on dynamic MR as a subtle peripheral enhancing nodule. Although the radiologic features are not specific, solitary necrotic nodule of the liver should be included in the differential diagnosis of hepatic metastasis.

The effects of blood on rapid urease testing for Helicobacter pylori in mucosal biopsies from the gastric antrum

BACKGROUND

While the eradication of Helicobacter pylori in patients with bleeding peptic ulcer disease (PUD) decreases the rate of ulcer re-bleeding, the sensitivity of the rapid urease test (RUT) for H. pylori diagnosis is lower in this setting. The aim of this study was therefore to determine if exposing a gastric biopsy specimen to blood before its use in the RUT (CLOtest) could account for these findings.

METHODS

In patients undergoing endoscopy for the evaluation of dyspepsia gastric mucosal biopsies were obtained for H. pylori diagnosis (RUT, microbiology, and histology). Mucosal biopsies from each patient were also exposed to blood for 15, 30 and 45 minutes before use in the RUT.

RESULTS

Using a combination of diagnostic tests (histology, microbiology and routine CLOtest) as the 'gold standard', the sensitivity, specificity, positive predictive value and negative predictive value of the CLOtest remained above 90% despite prior exposure of the gastric biopsy specimen to blood, and these values were not significantly different from the performance characteristics of the CLOtest processed in a routine manner.

CONCLUSION

The exposure of gastric mucosal biopsy specimens to blood alone is not the explanation for the reduced sensitivity of the RUT in patients with bleeding peptic ulcers.

Delayed colon perforation after palliative treatment for rectal carcinoma with bare rectal stent: a case report

In order to relieve mechanical obstruction caused by rectal carcinoma, a bare rectal stent was inserted in the sigmoid colon of a 70-year-old female. The procedure was successful, and for one month the patient made good progress. She then complained of abdominal pain, however, and plain radiographs of the chest and abdomen revealed the presence of free gas in the subdiaphragmatic area. Surgical findings showed that a spur at the proximal end of the bare rectal stent had penetrated the rectal mucosal wall. After placing a bare rectal stent for the palliative treatment of colorectal carcinoma, close follow-up to detect possible perforation of the bowel wall is necessary.

Expression of the bile salt export pump is maintained after chronic cholestasis in the rat

BACKGROUND & AIMS

This study assessed the expression of the recently identified adenosine triphosphate-dependent bile salt export pump and the functional ability to excrete bile salts in cholestatic models in the rat.

METHODS

The effects of common bile duct ligation, endotoxin, and ethinylestradiol on bile salt export pump messenger RNA levels, protein expression, and tissue localization were determined. Changes in the expression of 3 other hepatocyte membrane transporters (Na(+) taurocholate cotransporter, multispecific organic anion transporter, and P-glycoprotein) were also determined for comparison. Functional assessment of bile salt excretion was determined after bile duct ligation.

RESULTS

Expression of the bile salt export pump was diminished but relatively preserved compared with other membrane transporters. Tissue localization of the bile salt export pump persisted at the canalicular domain in all 3 models. In contrast, expressions of the Na(+) taurocholate cotransporter and multispecific organic anion transporter were more profoundly diminished. P-glycoprotein levels increased severalfold with common bile duct ligation but were unchanged with either endotoxin or ethinylestradiol. The capacity to excrete bile salts was relatively maintained 3 and even 14 days after bile duct ligation.

CONCLUSIONS

Alterations in expression of the bile salt export pump may account for the functional alterations of bile salt secretion observed in cholestasis. However, relative preservation of expression is associated with persistent bile salt excretion and may lessen the extent of liver injury produced by bile salt retention.

Elevated transglutaminase-induced bonds in PHF tau in Alzheimer's disease

Transglutaminase-induced epsilon-(gamma-glutamyl)lysine bonds covalently cross-link and polymerize peptides into insoluble high molecular weight protein aggregates resistant to degradation and proteolytic digestion. We investigated the hypothesis that excessive deposition of epsilon-(gamma-glutamyl)lysine bonds is a neuropathological mechanism which induces the polymerization of tau protein into stable aggregates leading to the formation of paired helical filaments (PHFs) which deposit into neurofibrillary tangles in Alzheimer's disease (AD) brain. We demonstrate a significant (45%) elevation in epsilon-(gamma-glutamyl)lysine cross-links in AD cortex as compared to control cortex. In vivo, PHF tau, and high and medium molecular weight neurofilament proteins have significantly greater cross-linking by epsilon-(gamma-glutamyl)lysine bonds in AD brains as compared to controls. The cross-linking of PHF tau occurs both intra-molecularly and inter-molecularly. The inter-molecular cross-linking of tau could account for the formation of high molecular weight tau polymers. These results suggest that transglutaminase-induced cross-linking of tau protein could play a role in the formation and stabilization of neurofibrillary tangles. Inhibition of transglutaminase-induced cross-linking may therefore, provide a novel strategy for the treatment of AD.

Modification of EWS/WT1 functional properties by phosphorylation

In many human cancers, tumor-specific chromosomal rearrangements are known to create chimeric products with the ability to transform cells. The EWS/WT1 protein is such a fusion product, resulting from a t(11;22) chromosomal translocation in desmoplastic small round cell tumors, where 265 aa from the EWS amino terminus are fused to the DNA binding domain of the WT1 tumor suppressor gene. Herein, we find that EWS/WT1 is phosphorylated in vivo on serine and tyrosine residues and that this affects DNA binding and homodimerization. We also show that EWS/WT1 can interact with, and is a substrate for, modification on tyrosine residues by c-Abl. Tyrosine phosphorylation of EWS/WT1 by c-Abl negatively regulates its DNA binding properties. These results indicate that the biological activity of EWS/WT1 is closely linked to its phosphorylation status.