Switching to tenofovir vs continuing entecavir for hepatitis B virus with partial virologic response to entecavir: a randomized controlled trial

Entecavir 0.5 mg (ETV) is widely used among treatment-naïve chronic hepatitis B (CHB) patients. However, 10%-30% of patients show partial virologic response (PVR) to the drug. If the hepatitis B virus (HBV) continues to replicate, the underlying liver disease may progress. Herein, we compared the efficacy of switching to tenofovir disoproxil fumarate (TDF) with that of continuing ETV in CHB patients with PVR to ETV. This was an open-label randomized controlled trial including CHB patients who had been receiving 0.5 mg of ETV for >12 months, but who still had detectable HBV DNA levels of >60 IU/mL without known resistance to ETV. Sixty patients were enrolled and 45 qualified for the study: Twenty-two patients were randomly assigned into the TDF group and 23 into the ETV group. After 12 months of treatment, the virologic response rate (HBV DNA <20 IU/mL) was significantly higher in the TDF group than in the ETV group, as measured using per-protocol analysis (55% vs 20%; P = .022) and intention-to-treat analysis (50% vs 17.4%; P = .020). The reduction in HBV DNA was greater (-1.13 vs -0.67 log₁₀ IU/mL; P = .024), and the mean HBV DNA level was lower (1.54 vs 2.01 log₁₀ IU/mL; P = .011) in the TDF group than in the ETV group. In conclusion, to achieve optimal response in CHB patients with PVR to ETV, switching to TDF would be a better strategy than continuing ETV. Appropriate modification of therapy would further improve the outcome of chronic HBV infection.

Risk Factors for Dropout From the Liver Transplant Waiting List of Hepatocellular Carcinoma Patients Under Locoregional Treatment

BACKGROUND

In new organ allocation policy, patients with hepatocellular carcinoma (HCC) experience a 6-month delay in being granted Model for End-Stage Liver Disease exception points. However, it may not be fair for patients at risk of early progression of HCC.

METHODS

All patients who were diagnosed as United Network for Organ Sharing (UNOS) stage 1 or 2 of HCC between January 2004 and December 2012 were included. Patients who received surgical resection or liver transplant (LT) as a primary treatment and who did not receive any treatment for HCC were excluded. Patients with baseline Model for End-Stage Liver Disease score ≥22 were also excluded because they have a higher chance of receiving LT. Patients who developed extrahepatic progression within 1 year were considered as high-risk for early recurrence after LT.

RESULTS

A total of 586 patients were included. Mean (SD) age was 59.9 (10.3) years and 409 patients (69.8%) were men. The cumulative incidence of estimated dropout was 8.9% at 6 months; size of the maximum nodule (≥3 cm) and nonachievement of complete response were independent factors. Extrahepatic progression developed in 16 patients (2.7%) within 1 year; size of the maximum nodule (4 cm) and alpha-fetoprotein level (>100 ng/mL) were independent predictors.

CONCLUSIONS

The estimated dropout rate from the waiting list within 6 months was 8.9%. Advantage points might be needed for patients with maximum nodule size ≥3 cm or those with noncomplete response. However, in patients with maximum nodule size ≥4 cm or alpha-fetoprotein level >100 ng/mL, caution is needed.

Effect of weed extracts against pulse beetle, Callosobruchus chinensis L. (Coleoptera: Bruchidae) of mung bean

The n-hexane extracts of the weeds ‘bhatpata’ Clerodendrum viscosum, ‘kashiature’ Cassia tora, ‘dhakishak’ Dryoptris filix-max, ‘bonmorich’ Croton bonpalandianum and ‘ghagra’ Xanthium strumarium were used to evaluate their effectiveness for suppressing pulse beetle, Callosobruchus chinensis reared on mung bean Vigna radiata grains. The investigations were done with 1, 2 and 4% n-hexane extracts of the weeds and an untreated control. The weed extracts exhibited considerable effectiveness which varied with weed species, concentrations and exposure durations. The higher concentrations showed the higher rate of insect mortality, fecundity, adult emergence inhibition, and grain protection. The LC50 values of the extracts ranged from 5.3 to 7.8, 4.7 to 6.5 and 4.1 to 6.0 g/100 ml at 24, 48 and 72 hours after treatment, respectively. The fecundity inhibition varied from 31.7 to 78.7%, adult emergence inhibition from 33.8 to 81.1%, and grain damage inhibition from 10.3 to 60.1% when ‘bhatpata’ with concentration of 1 g/100 ml and ‘ghagra’ with concentration of 4g/100 ml were applied, respectively. Among the tested weeds, ghagra (4g/100 ml) showed better efficacy against C. chinensis compared to other tested extracts and may be suggested to control pulse beetle and protection of mung bean grains.Bangladesh J. Agril. Res. 41(1): 75-84, March 2016

Electrical properties and surface morphology of SiO(x)-Pt nano-composite thin films

Recently, ceramic metals (cermets) have been widely investigated for use as embedded resistor materials. In this study, SiO-Pt nano-composite cermets were developed to control the resitivity and temperature coefficients of resistance (TCR) of embedded thin film resistors. The SiO-Pt nano-composite was prepared by the co-sputtering of a SiO(x) target and Pt chips onto glass. The experiments were conducted Pt concentrations in order to find the optimum conditions to achieve a high resistivity and low TCR. The electrical properties of the sputtered SiO-Pt thin films were investigated by probe station and their crystal structures were observed by X-Ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). The surface morphology was observed by field emission scanning electron microscopy (FE-SEM) and high resolution transmission electron microscopy (HR-TEM). It was found that the Pt particles with a size of 3 approximately 5 nm were uniformly dispersed in the SiO matrix. A stable resistivity value of 26000 approximately 57000 microomega x cm and TCR value of -197 approximately -322 ppm/K were obtained at 3.5 approximately 3.7 at.% Pt.

Three functional isoforms of GAR-2, a Caenorhabditis elegans G-protein-linked acetylcholine receptor, are produced by alternative splicing

We have previously isolated a cDNA clone from Caenorhabditis elegans that encodes a novel form of G-protein-linked acetylcholine receptor, termed GAR-2. GAR-2 is similar to but pharmacologically distinct from muscarinic acetylcholine receptors. Here we report the identification of two gar-2 cDNA clones that are different from the previous one. These newly identified cDNAs encode polypeptides of 664 and 627 amino acids, whereas the previous one encodes a polypeptide of 614 amino acids. The three GAR-2 isoforms, which differ only in the third intracellular loop, arise from alternative splicing. Electrophysiological analyses using the Xenopus oocyte system showed that all three GAR-2 isoforms couple to the activation of G-protein-gated inwardly rectifying K+ (GIRK1) channel with similar drug specificity. Our results indicate that alternative splicing plays an important role in promoting molecular diversity of G-protein-linked acetylcholine receptors in C. elegans.

Isolation of a unique membrane protein from Naegleria fowleri

Naegleria fowleri, an amoeboflagellate, is the causative agent of Primary Amoebic Meningoencephalitis, a fulminating disease of the central nervous system. In order to elucidate the mechanisms of pathogenicity of this amoeba, a cDNA expression library was prepared from N. fowleri RNA. A specific protein was found to be expressed from a cDNA clone designated Mp2CL5. Northern blot analysis showed that the Mp2CL5 mRNA was expressed in pathogenic N. fowleri but was not expressed in non-pathogenic Naegleria species nor in Acanthamoeba. Western blot analysis using anti-N. fowleri antiserum demonstrated that IPTG-induced Escherichia coli Mp2CL5 expressed a 23-kDa recombinant protein. The Mp2CL5 recombinant protein was histidine-tagged and purified to homogeneity from E. coli. A polyclonal rabbit antiserum was prepared against the purified Mp2CL5 recombinant protein. This antibody was used to further characterize the Mp2CL5 native protein expressed by N. fowleri. Western blot analysis in conjunction with immunofluorescence microscopy demonstrated the presence of a native protein of 17 kDa on the plasma membrane of N. fowleri trophozoites. The native N. fowleri protein was expressed in the logarithmic phase of trophozoite growth and the production of this protein increased through the stationary phase of growth. Studies are in progress to examine further its role as a virulence factor.

MR findings of the spinal paraganglioma : report of three cases

Extraadrenal paragangliomas involving the spine is less common and usually takes the form of intradural compression of the cauda equina. The authors report three cases of spinal paragangliomas resulting in extradural spinal cord compression and their MR findings. The MR imaging revealed a well-demarcated extradural mass with low to intermediate signal intensity on T1-weighted images and intermediate to high signal intensity on T2-weighted images compared to paravertebral muscles. After Gd-DTPA administration, heterogeneous and intense enhancement was found. Multiple punctate and serpiginous structures of signal void due to high-velocity flow were noted around and within the tumors on all sequences. In one case, the signal void structures were well corresponded with feeding arteries on angiography. These may be the characteristic findings of the extraadrenal paraganglioma involving the spine.

Characterization of GAR-2, a novel G protein-linked acetylcholine receptor from Caenorhabditis elegans

We have previously identified two G protein-linked acetylcholine receptors (GARs), GAR-1 and GAR-3, in the nematode Caenorhabditis elegans. Whereas GAR-3 is a homologue of muscarinic acetylcholine receptors (mAChRs), GAR-1 is similar to but pharmacologically distinct from mAChRs. In the current work we isolated a new type of GAR using C. elegans genome sequence information. This receptor, named GAR-2, consists of 614 amino acid residues and has seven putative transmembrane domains. Database searches indicate that GAR-2 is most similar to GAR-1 and closely related to GAR-3/mAChRs. The overall amino acid sequence identities to GAR-1 and GAR-3 are approximately 32 and approximately 23%, respectively. When GAR-2 was coexpressed with the G protein-activated inwardly rectifying K(+) (GIRK1) channel in Xenopus oocytes, acetylcholine was able to evoke the GIRK current in a dose-dependent fashion. Oxotremorine, a classical muscarinic agonist, had little effect on the receptor, indicating that GAR-2 is pharmacologically different from mAChRs but rather similar to GAR-1. GAR-2 differs from GAR-1, however, in that it showed virtually no response to muscarinic antagonists such as atropine, scopolamine, and pirenzepine. Expression studies using green fluorescent protein reporter gene fusion revealed that GAR-2 is expressed in a subset of C. elegans neurons, distinct from those expressing GAR-1. Together with our previous reports, this study demonstrates that diverse types of GARs are present in C. elegans.

"Daughter cyst" sign: a sonographic finding of ovarian cyst in neonates, infants, and young children

OBJECTIVE

The purpose of this study was to assess the value of the "daughter cyst" sign, a sonographic finding of neonatal ovarian cysts, in differentiating ovarian cysts from other cystic masses in neonates, infants, and young children.

SUBJECTS AND METHODS

In a prospective study, 23 neonates, infants, and young children (age range, 1 day to 36 months) with a lower abdominal cystic mass underwent sonography. We defined the daughter cyst sign as the presence of a small cyst along the wall of a cystic mass. The diagnosis of ovarian cyst was made when this sign was present. Detailed pathologic correlation was available in four ovarian cysts. The size, wall thickness, and contents of the cysts were also evaluated.

RESULTS

The 23 cystic lesions included ovarian cyst (n = 11), lymphangioma (n = 3), enteric duplication cyst (n = 3), enteric cyst (n = 1), meconium pseudocyst (n = 2), hydrometrocolpos (n = 2), and urachal cyst (n = 1). The daughter cyst sign was seen in nine (82%) of 11 ovarian cysts but in none of the other cystic lesions. Sensitivity, specificity, and positive predictive value of the daughter cyst sign for differentiating ovarian cysts from other cystic lesions were 82%, 100%, and 100%, respectively. The daughter cyst corresponded to an ovarian follicle on pathologic examination.

CONCLUSION

The daughter cyst sign is a specific sonographic finding for an ovarian cyst and may be useful in differentiating uncomplicated ovarian cysts from other cystic masses in neonates, infants, and young children.

Role of RpoS and AlgT in Pseudomonas aeruginosa biofilm resistance to hydrogen peroxide and monochloramine

The role of two sigma factors, AlgT and RpoS, in mediating Pseudomonas aeruginosa biofilm resistance to hydrogen peroxide and monochloramine was investigated. Two knock out mutant strains, SS24 (rpoS-) and PAO6852 (algT-), were compared with a wild type, PAO1, in their susceptibility to monochloramine and hydrogen peroxide. When grown as biofilms on alginate gel beads (mean untreated areal cell density 3.7 +/- 0.27 log cfu cm-2) or on glass slides (mean untreated areal cell density 7.6 +/- 0.9 log cfu cm-2), wild type bacteria exhibited reduced susceptibility to both antimicrobial agents in comparison with suspended cells. On alginate gel beads, all strains were equally resistant to monochloramine. rpoS- and algT- gel bead biofilms of 24-hour-old were more susceptible to hydrogen peroxide disinfection than were biofilms formed by PAO1. Biofilm disinfection rate coefficients for the two mutant strains were statistically indistinguishable from planktonic disinfection rate coefficients, indicating complete loss of biofilm resistance. While 48-hour-old algT- biofilm cells became resistant to hydrogen peroxide, 48-hour-old rpoS- biofilm cells remained highly susceptible. With the thicker biofilms formed on glass coupons, all strains were equally resistant to both hydrogen peroxide and monochloramine. It is concluded that while RpoS and AlgT may play a transient role in protecting thin biofilms from hydrogen peroxide, these sigma factors do not mediate resistance to monochloramine and do not contribute significantly to the hydrogen peroxide resistance of thick biofilms.

Effect of rpoS mutation on the stress response and expression of virulence factors in Pseudomonas aeruginosa

The sigma factor RpoS (sigmaS) has been described as a general stress response regulator that controls the expression of genes which confer increased resistance to various stresses in some gram-negative bacteria. To elucidate the role of RpoS in Pseudomonas aeruginosa physiology and pathogenesis, we constructed rpoS mutants in several strains of P. aeruginosa, including PAO1. The PAO1 rpoS mutant was subjected to various environmental stresses, and we compared the resistance phenotype of the mutant to that of the parent. The PAO1 rpoS mutant was slightly more sensitive to carbon starvation than the wild-type strain, but this phenotype was obvious only when the cells were grown in a medium supplemented with glucose as the sole carbon source. In addition, the PAO1 rpoS mutant was hypersensitive to heat shock at 50 degrees C, increased osmolarity, and prolonged exposure to high concentrations of H2O2. In accordance with the hypersensitivity to H2O2, catalase production was 60% lower in the rpoS mutant than in the parent strain. We also assessed the role of RpoS in the production of several exoproducts known to be important for virulence of P. aeruginosa. The rpoS mutant produced 50% less exotoxin A, but it produced only slightly smaller amounts of elastase and LasA protease than the parent strain. The levels of phospholipase C and casein-degrading proteases were unaffected by a mutation in rpoS in PAO1. The rpoS mutation resulted in the increased production of the phenazine antibiotic pyocyanin and the siderophore pyoverdine. This increased pyocyanin production may be responsible for the enhanced virulence of the PAO1 rpoS mutant that was observed in a rat chronic-lung-infection model. In addition, the rpoS mutant displayed an altered twitching-motility phenotype, suggesting that the colonization factors, type IV fimbriae, were affected. Finally, in an alginate-overproducing cystic fibrosis (CF) isolate, FRD1, the rpoS101::aacCI mutation almost completely abolished the production of alginate when the bacterium was grown in a liquid medium. On a solid medium, the FRD1 rpoS mutant produced approximately 70% less alginate than did the wild-type strain. Thus, our data indicate that although some of the functions of RpoS in P. aeruginosa physiology are similar to RpoS functions in other gram-negative bacteria, it also has some functions unique to this bacterium.

MRI of round ligament leiomyoma associated with Mayer-Rokitansky-Kuster-Hauser syndrome

We report the magnetic resonance appearance of a case of round ligament leiomyoma that presented as a rapid growing inguinal mass in a patient with Mayer-Rokitansky-Kuster-Hauser syndrome.

Sonographic diagnosis of paraovarian cysts: value of detecting a separate ipsilateral ovary

OBJECTIVE

The purpose of this study was to determine the frequency with which sonographic detection of a normal separate ipsilateral ovary enables the diagnosis of paraovarian cysts.

MATERIALS AND METHODS

We reviewed the initial sonographic reports, sonograms, and medical records of 42 patients with surgically proved paraovarian cysts. All sonograms were obtained with a 3.5-MHz transabdominal probe. The location, size, shape, wall thickness, internal echoes of the cyst, and visualization or nonvisualization of the ipsilateral ovaries were recorded during sonographic examination.

RESULTS

Forty-six paraovarian cysts were identified in 42 patients. One patient had bilateral cysts, and one had multiple (four) unilateral cysts. A teratoma in one patient and an ovarian cyst in another coexisted with a paraovarian cyst in the same adnexa. With the exception of these two, 31 (76%) of 41 ovaries abutted by cysts were detected. All detectable ovaries were normal. With one exception, all cysts were thin walled and unilocular, and 43 of 46 were anechoic. During surgery, two patients were found to have cyst torsion, two were found to have papillary serous cystadenoma, and one was found to have both.

CONCLUSION

Unlike the findings of previous reports, our results indicate that most patients with paraovarian cysts have a separate, normal ipsilateral ovary that can be detected easily by means of transabdominal sonography, thus aiding in distinguishing paraovarian from true ovarian cysts.

MR findings of secondary hemochromatosis: transfusional vs erythropoietic

OBJECTIVE

The aim of this study was to demonstrate the MR characteristics of secondary hemochromatosis (transfusional versus erythropoietic).

MATERIALS AND METHODS

Magnetic resonance images of five patients with transfusional (n = 3) or erythropoietic (n = 2) hemochromatosis were reviewed.

RESULTS

The liver of all patients had low signal intensity in all pulse sequences. The spleen had low signal intensity in all patients with transfusional iron overload, but normal signal intensity in erythropoietic hemochromatosis, which had similar MR findings to idiopathic hemochromatosis. However, the pancreas had variable signal intensity.

CONCLUSION

On MRI the signal intensity of the spleen may allow distinction between transfusional and erythropoietic hemochromatosis.

Cloning, sequencing and overexpression of cobA which encodes ATP:corrinoid adenosyltransferase in Salmonella typhimurium

The cobA gene of Salmonella typhimurium was cloned, sequenced and overexpressed. A 990-bp HpaI-SacI fragment was cloned into the multiple cloning site of plasmid pSU19, an intermediate-copy-number vector. DNA sequence analysis established that cobA is 588 bp in length and codes for a protein with a predicted molecular weight of 21.7 kDa. However, the CobA protein expressed from the T7 promoter migrated as a 25-kDa protein on SDS-polyacrylamide gels. A high degree of identity at the amino acid sequence level was established between the CobA, Pseudomonas denitrificans CobO and Escherichia coli BtuR proteins. P. denitrificans CobO has been shown to be a ATP:corrinoid adenosyltransferase enzyme. Based on the similarities between CobO and CobA, and the phenotypes of cobA mutants, we suggest that CobA is the ATP:corrinoid adenosyltransferase of S. typhimurium.

Pediatric gastric volvulus--experience with 7 cases

Gastric volvulus, organoaxial or mesenterioaxial, is a rare condition in infancy and childhood. We experienced 7 cases of pediatric gastric volvulus, consisting of 3 cases of secondary gastric volvulus due to left diaphragmatic eventration or paraesophageal hernia and 4 cases of idiopathic gastric volvulus. Of 7 cases, five were organoaxial in type and two were mesenterioaxial. The main symptoms of secondary gastric volvulus were vomiting and respiratory difficulty whereas those of idiopathic gastric volvulus were abdominal distension and weight loss with or without failure to thrive. It may be suspected on plain abdominal radiographs and usually confirmed by upper gastrointestinal series. Upper gastrointestinal series in organaxial volvulus demonstrated characteristic findings such as reversal of the greater and lesser curvatures and two air-fluid levels. In mesenterioaxial volvulus, the stomach was rotated into inverted position with pyloroantral obstruction showing a beak appearance. The three patients with secondary volvulus underwent repair of associated defect with or without gastropexy and the 3 patients with idiopathic volvulus underwent anterior gastropexy or gastrostomy. In those with idiopathic gastric volvulus, there was no obvious cause such as laxity of the perigastric ligaments. The operative results were satisfactory except for the three patients with idiopathic gastric volvulus whose abdomen remained distended regardless of weight gain.

Childhood intussusception: US-guided hydrostatic reduction

Over a 30-month period, real-time ultrasound (US) was performed in 116 children with suspected intussusception. US findings were positive in all 75 cases of intussusception. Except in one case of transient small-bowel intussusception, the authors immediately attempted US-guided hydrostatic reduction in all cases. Reduction was successful in 63 cases (85%), as demonstrated with US and resolution of signs and symptoms of intussusception. Negative sonograms were confirmed with clinical follow-up. Among 11 failed cases, reduction with barium enema was attempted in six, but all attempts failed. No complications have occurred to date. The authors conclude that US is a reliable diagnostic screening modality in cases of suspected intussusception and that US-guided hydrostatic reduction is a promising technique in nonoperative treatment.

Right perirenal space. Computed tomography evidence of communication between the bare area of the liver

Computed tomography (CT) images from one cadaver and 11 patients with perirenal fluid collection were reviewed to study whether the right perirenal space communicates with the bare area of the liver. CT of a cadaver obtained after meticulous right perirenal injection of contrast media showed that contrast media extended superiorly into the bare area of the liver. CT of 11 patients with right perirenal hemorrhage or infection showed that fluid collection within the right perirenal space continued upward, crossing the coronary ligament, extending into the bare area of the liver. The inferior vena cava were completely or partially surrounded by fluid. CT of two patients with bleeding hepatocellular carcinoma showed that blood in the bare area continued extending downward into the perirenal space. We conclude that the right perirenal space is open toward the bare area of the liver and fluid collection within one space may communicate with the other space across the coronary ligament.