Surgical Versus Non-Surgical Treatment for Thoracolumbar Burst Fractures Without Neurological Deficit: A Systematic Review and Meta-Analysis

STUDY DESIGN

A systematic review and meta-analysis.

OBJECTIVE

To update the systematic review comparing the outcomes between surgical and non-surgical treatment for thoracolumbar burst fractures without neurological deficit.

METHODS

We registered a protocol in PROSPERO (ID: CRD42021291769) and searched Medline, Embase, Web of Science, and Google Scholar databases. Surgical and non-surgical treatments were compared in patients with thoracolumbar burst fractures without neurological deficits. Predefined outcomes at ≥6 months included pain (defined as a visual analog scale [VAS] of 0-100), functional outcomes (Oswestry Disability Index [ODI] of 0-50 and Roland-Morris Disability Questionnaire [RMDQ] of 0-24), and kyphotic angulation.

RESULTS

Nineteen studies involving 1056 patients were included in the analyses. For outcomes at ≥6 months, little to no difference was found in pain VAS score (mean difference, .95 [95% confidence interval {CI}, -6.02 to 7.92]; 827 participants; 15 studies; I2 = 92%), ODI (mean difference, -1.40 [95% CI, -5.11 to 2.31]; 446 participants; 7 studies; I2 = 79%), and RMDQ (mean difference, -.73 [95% CI, -5.13 to 3.66]; 216 participants; 5 studies; I2 = 77%). The kyphotic angulation in the surgery group was 6.35° lower than that in the non-surgery group (mean difference, -6.56° [95% CI, -10.26° to -2.87°]; 527 participants; ten studies; I2 = 86%). The trial sequential analysis indicated all outcomes reached adequate statistical power. The certainty of the evidence for all 4 outcomes was very low. For the analysis of minimally invasive procedures compared to traditional open surgeries, a statistically significant subgroup difference was found for VAS and ODI (P < .01 and P < .04, respectively).

CONCLUSION

Surgical and non-surgical treatments showed little or no difference in outcomes at ≥6 months. This review provides a conclusion with adequate statistical power by including non-randomized studies. However, non-randomized studies also lowered the certainty of the evidence to a very low level.

A Wearable Assistant Device for the Hearing Impaired to Recognize Emergency Vehicle Sirens with Edge Computing

Wearable assistant devices play an important role in daily life for people with disabilities. Those who have hearing impairments may face dangers while walking or driving on the road. The major danger is their inability to hear warning sounds from cars or ambulances. Thus, the aim of this study is to develop a wearable assistant device with edge computing, allowing the hearing impaired to recognize the warning sounds from vehicles on the road. An EfficientNet-based, fuzzy rank-based ensemble model was proposed to classify seven audio sounds, and it was embedded in an Arduino Nano 33 BLE Sense development board. The audio files were obtained from the CREMA-D dataset and the Large-Scale Audio dataset of emergency vehicle sirens on the road, with a total number of 8756 files. The seven audio sounds included four vocalizations and three sirens. The audio signal was converted into a spectrogram by using the short-time Fourier transform for feature extraction. When one of the three sirens was detected, the wearable assistant device presented alarms by vibrating and displaying messages on the OLED panel. The performances of the EfficientNet-based, fuzzy rank-based ensemble model in offline computing achieved an accuracy of 97.1%, precision of 97.79%, sensitivity of 96.8%, and specificity of 97.04%. In edge computing, the results comprised an accuracy of 95.2%, precision of 93.2%, sensitivity of 95.3%, and specificity of 95.1%. Thus, the proposed wearable assistant device has the potential benefit of helping the hearing impaired to avoid traffic accidents.

Clinicopathological and molecular differences in colorectal cancer according to location

PURPOSE

The incidence, pathogenesis, molecular pathways, and outcomes of colorectal cancer vary depending on the location of the tumor. This study aimed to compare the difference in tumor characteristics and the outcome between right-sided colon cancer and left-sided colorectal cancer (LCRC).

MATERIALS AND METHODS

A total of 1503 patients with colorectal cancer who underwent surgery at the Taipei Veterans General Hospital between 2000 and 2010 were enrolled in this study. Right-sided colon cancer was defined as cancers in the cecum, ascending colon, and transverse colon, while LCRC was defined as cancers in the splenic flexure colon, descending colon, sigmoid colon, and rectum. The endpoint was overall survival. The mutations were detected via polymerase chain reaction and MASS array. The prognostic value was determined using the log-rank test and the Cox regression analysis.

RESULTS

A total of 407 and 1096 cases were classified as right-sided colon cancer and LCRC, respectively. Compared to patients with LCRC, those with right-sided colon cancer had more mucinous type cancer (7.4% vs. 3.5%), poorly differentiated tumor (11.5% vs. 3.6%), and advanced tumor-node-metastasis stage. The risk for peritoneal tumor seeding was higher in the right-sided colon cancer group (12.8% vs. 5.7%). Overall survival was better in LCRC than in right-sided colon cancer ( P=0.036).

CONCLUSIONS

In our study, right-sided colon cancer had a more advanced tumor stage, a higher risk of peritoneal metastasis, and a poorer outcome than LCRC. Moreover, right-sided colon cancer had more gene mutations in BRAF, KRAS, SMAD4, TGF-β, PIK3CA, PTEN, AKT1, and high microsatellite instability.

Ageing and infection

An increased morbidity and mortality due to infectious disease has been noted in the ageing. Two alternative explanations may account for this. Changes in the immune system and inflammatory responses with age or an increase in age-related diseases may underlie the increased susceptibility. A review of studies of healthy older individuals demonstrates changes in the immune system with ageing but minimal change in the inflammatory response. Investigations of severe infection in older nursing-home patients requiring hospitalization indicate that infection as a cause of admission and death is significantly more common in individuals who are bedridden because of serious cardiovascular or neurological disease and require urinary catheterization. The evidence indicates that underlying disease, not the senescence of host resistance, leads to severe infection in the ageing.

Chalcone inhibits the proliferation of human breast cancer cell by blocking cell cycle progression and inducing apoptosis

Chalcones are discussed to represent cancer preventive food components in a human diet that is rich in fruits and vegetables. In this study, we examined chalcone (1,3-diphenyl-2-propenone) for its effect on proliferation in human breast cancer cell lines, MCF-7 and MDA-MB-231. The results showed that chalcone inhibited the proliferation of MCF-7 and MDA-MB-231 by inducing apoptosis and blocking cell cycle progression in the G2/M phase. Immunoblot assay showed that chalcone significantly decreased the expression of cyclin B1, cyclin A and Cdc2 protein, as well as increased the expression of p21 and p27 in a p53-independent manner, contributing to cell cycle arrest. An enhancement in Fas/APO-1 and its two form ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), was responsible for the apoptotic effect induced by chalcone. In addition, chalcone also triggered the mitochondrial apoptotic signaling by increasing the amount of Bax and Bak and reducing the level of Bcl-2 and Bcl-X(L), and subsequently activated caspase-9 in MCF-7 and MDA-MB-231 cells. Taken together, our study suggests that the blockade of cell cycle progression and initiation of cell apoptotic system may participate in the antiproliferative activity of chalcone in human breast cancer cells.

The antiproliferative activity of prodelphinidin B-2 3′-O-gallate from green tea leaf is through cell cycle arrest and Fas-mediated apoptotic pathway in A549 cells

Prodelphinidin B-2 3'-O-gallate, a proanthocyanidin gallate isolated from green tea leaf, was investigated for its anti-proliferative activity in human non-small cell lung cancer A549 cells. The results showed that prodelphinidin B-2 3'-O-gallate inhibited the proliferation of A549 cells with no detectable toxic effects on normal WI-38 cells as measured by the XTT assay. Flow cytometric analysis showed that prodelphinidin B-2 3'-O-gallate blocked cell cycle progression in the G0/G1 phase. In addition, prodelphinidin B-2 3'-O-gallate effectively induced A549 cell apoptosis as determined by assessing the nucleosome level in cytoplasm. Enzyme-linked immunosorbent assay showed that the G0/G1 phase arrest is due to p53-independent induction of p21/WAF1. An enhancement in Fas/APO-1 and its two form ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), might be responsible for the apoptotic effect induced by prodelphinidin B-2 3'-O-gallate. We suggested that prodelphinidin B-2 3'-O-gallate's activities might be potentially contribute to its overall chemopreventive effects against lung cancer, and can possibly be considered for future therapeutic application.

Aspirin differentially regulates endotoxin-induced IL-12 and TNF-alpha production in human dendritic cells

OBJECTIVE

In the development of autoimmune diseases, dendritic cells (DC) play critical roles. Here, we examined the effect of aspirin on lipopolysaccharide (LPS)-induced DC activation.

METHODS

The monocyte-derived DC were established. The cytokine production was measured by ELISA, reverse transcriptase/polymerase chain reaction, or intracellular staining analyzed by flow cytometry. The expression of cell surface molecules was determined by flow cytometry.

RESULTS

Aspirin inhibited LPS-induced DC maturation and costimulatory molecules expression. Aspirin, at therapeutic concentrations, also decreased LPS-induced IL-12 and IL-10 production. In contrast, the LPS-induced TNF-alpha production was enhanced by aspirin. The differential effects of aspirin on IL-12 and TNF-alpha production may not be due to down-regulation of cyclooxygenase activities.

CONCLUSION

The various effects of aspirin on LPS-stimulated DC may influence the understanding of the diverse immunomodulatory mechanisms of this anti-inflammatory drug.

Effect of shear stress on cultivation of Bacillus thuringiensis for thuringiensin production

Cultivation of Bacillus thuringiensis for thuringiensin production is a mixed-growth-associated system. Cultivation conditions should be different during the cell growth stage and production stage. In this study, agitation speed and aeration rate were varied during the exponential growth phase and stationary phase in order to investigate the effect of shear stress via agitation on cultivation of B. thuringiensis for thuringiensin production. It was found that shear stress had a significant effect on thuringiensin production during the stationary phase. By decreasing the agitation speed during the stationary phase, product formation was increased up to 43%.

Infectious Pancreatic Necrosis Virus RNA Cleavage In Vitro by Hammerhead Ribozymes and Enhancement of Ribozyme Catalysis by Oligonucleotide Facilitators

Infectious pancreatic necrosis virus (IPNV), an aquatic birnavirus, has a bisegmented double-stranded RNA genome consisting of a 3.2-kb A segment and a 2.9-kb B segment. To determine the function of IPNV's viral proteins and to study the effects of viral RNA cleavage by hammerhead ribozymes, we cloned and sequenced the IPNV E1S strain of the A segment. After sequencing, we continued to study the virus pathogens inhibited by ribozyme cleavage and analyzed the cleavage of the virus RNA in vitro. The templates (VP2, 1220 bp) for in vitro transcription of S569 and S969 (substrates 569 and 969 bp in length) were synthesized by polymerase chain reaction. The DNA templates of hammerhead ribozymes targeted different sites in the partial sense RNA of IPNV. These templates were chemically synthesized RNAs prepared by runoff transcription of amplification products or synthetic DNA templates containing a T7 RNA polymerase promoter, and were used to characterize several properties of the cleavage reaction at 25 degrees C in 12 mM Mg(2+). Under this condition (25 degrees C, 12 mM Mg(2+)), the hammerhead ribozymes formed an estimated fraction of product during the reaction of only 30% in cleaving long RNA substrates in vitro. Short DNA facilitators (12 or 24-mers) that bind adjacent to either the 3' or 5' end of the ribozyme enhanced the rate of cleavage of the long RNA substrates containing 569 and 969 nucleotides, respectively, in trans. The hammerhead ribozymes with 3'-end facilitators reacted more efficiently (i.e., 65%).

The use of solid-phase microextraction--gas chromatography in forensic analysis

A thorough review of the application of solid-phase microextraction (SPME) combined with gas chromatography for the analysis of forensic specimens is presented, including experimental results for several recent applications. The SPME applications covered in this comprehensive review include ignitable liquid residues (also referred to as accelerants), explosive traces, drugs and poisons from biological specimens, and other forensic applications. Recently developed SPME methods are also presented, including the analysis of ignitable liquid residues on human skin, odor signatures, and several drug applications such as free-fraction antipsychotic drug levels, blood alcohol casework, drink-tampering analysis, and gamma-hydroxybutyrate identification without the need for derivatization. SPME is shown to be an inexpensive, rapid, and sensitive method for the analysis of a variety of forensic specimens.

Diagnosis of Penaeus monodon-type baculovirus by PCR and by ELISA of occlusion bodies

The black tiger prawn Penaeus monodon is a valuable aquaculture product in Taiwan. Two specific diagnostic methods were established for P. monodon-type baculovirus, one using polymerase chain reaction (PCR) technology and the other enzyme-linked immunosorbent assay (ELISA) technology. Monodon-type baculovirus (MBV) was purified by sucrose gradient centrifugation from occlusion bodies of MBV-infected postlarvae of P. monodon. MBV DNA was subsequently purified from the occlusion bodies and its presence was confirmed by PCR using primers of the polyhedrin gene. Based on conserved sequences of the DNA polymerase genes of Autographa californica nuclear polyhedrosis virus (AcMNPV) and Lymantria dispar nuclear polyhedrosis virus (LdMNPV), primers were designed and synthesized to yield a 714 bp PCR fragment from MBV. However, the sequence of this fragment revealed low homology with that of LdMNPV and AcMNPV. From the DNA sequence of this fragment, a second set of primers was designed, and using these primers, a 511 bp DNA fragment was amplified only when MBV DNA was the template. DNA templates from AcMNPV, white spot syndrome diseased shrimp, or PMO cells (a cell line derived from the Oka organ of Penaeus monodon) did not give any amplified DNA fragment. Therefore, this primer pair was specific for the diagnosis of MBV. By using intraspleenic immunization of rabbits with purified MBV occlusion bodies, a polyclonal rabbit antiserum against MBV was obtained. This antiserum could detect nanogram levels of MBV, but did not cross react with white spot syndrome virus (WSSV), homogenates of PMO cells, postlarvae, hepatopancreatic tissue or intestinal tissue of black tiger prawns by competitive ELISA. This sensitive method could detect MBV even in tissue homogenates.

Ferrocene-based electroactive derivatizing reagents for the rapid selective screening of alcohols and phenols in natural product mixtures using electrospray-tandem mass spectrometry

The alcohols and phenols of oil of cloves, lemon oil, rose absolut, and oil of peppermint were derivatized with ferroceneoyl azide to generate their ferroceneoyl carbamates. These derivatives are selectively detected at the attomole level, in nanomolar concentrations by electrospray-tandem mass spectrometry (ES-MS/MS) without the need for sample cleanup. The ES-MS/MS analyses of the four essential oils revealed all the expected alcohols, and, in the case of lemon oil, it detected alpha-terpineol as a trace component that was not readily observed by GC-MS. The ES-MS/MS analyses complements the more conventional GC-MS analysis. The ES-MS method has the advantage of speed, selectivity, and sensitivity over GC-MS for detection of a targeted alcohol of a specific mass or structural type. The ES-MS method does not require a chromatographic separation of the components to accomplish its task. In contrast, GC-MS remains the preferred method for the determination of the total constituents of an oil. The ES-MS method may produce artifact ions, especially if the sample is wet and an excess of the ferroceneoyl azide is used; however, the artifacts did not interfere with the analyses.

Evaluation of the protective immunogenicity of the N, P, M, NV and G proteins of infectious hematopoietic necrosis virus in rainbow trout oncorhynchus mykiss using DNA vaccines

The protective immunogenicity of the nucleoprotein (N), phosphoprotein (P), matrix protein (M), non-virion protein (NV) and glycoprotein (G) of the rhabdovirus infectious hematopoietic necrosis virus (IHNV) was assessed in rainbow trout using DNA vaccine technology. DNA vaccines were produced by amplifying and cloning the viral genes in the plasmid pCDNA 3.1. The protective immunity elicited by each vaccine was evaluated through survival of immunized fry after challenge with live virus. Neutralizing antibody titers were also determined in vaccinated rainbow trout Oncorhynchus mykiss fry (mean weight 2 g) and 150 g sockeye salmon Oncorhynchus nerka. The serum from the 150 g fish was also used in passive immunization studies with naive fry. Our results showed that neither the internal structural proteins (N, P and M) nor the NV protein of IHNV induced protective immunity in fry or neutralizing antibodies in fry and 150 g fish when expressed by a DNA vaccine construct. The G protein, however, did confer significant protection in fry up to 80 d post-immunization and induced protective neutralizing antibodies. We are currently investigating the role of different arms of the fish immune system that contribute to the high level of protection against IHNV seen in vaccinated fish.

Infectious pancreatic necrosis virus induces apoptosis due to down-regulation of survival factor MCL-1 protein expression in a fish cell line

Infectious pancreatic necrosis virus (IPNV), a member of the virus family Birnaviridae, causes an acute, contagious disease in a number of economically important fish species. CHSE-214, a Chinook salmon embryonic cell line, when infected by IPNV showed morphological and biochemical features of apoptosis, including an intense DNA laddering pattern and blebbing of the plasma membrane, followed by formation of apoptotic bodies. The Mcl-1 gene product proved to be a member of the Bcl-2 gene family, and like Bcl-2 had the capacity to promote cell viability. Here, we investigated the pattern of expression of Mcl-1 in CHSE-214 cells infected by IPNV. We found that the Mcl-1 level decreased markedly in cells undergoing apoptosis after IPNV infection. This decrease was rapid during the first 8 h postinfection and preceded cell death. Furthermore, we found that drugs including cycloheximide, genistein and EDTA either prevented the decline in Mcl-1 levels or blocked the intense DNA laddering pattern. Other drugs like serine proteinase inhibitor, 400 microg/ml aprotinin, 400 microg/ml leupeptin and 100 microg/ml tryphostin did not. The virus gene expression pattern was examined by Western blot using antivirion polyclonal antibody and was blocked during treatment with cycloheximide, genistein and EDTA but not by serine proteinase, aprotinin, leupeptin or tryphostin. Together the data showed a striking correlation between virus replication and Mcl-1 expression in CHSE-214 cells, suggesting that the virus gene expression has a possible involvement with Mcl-1 in the regulation of apoptosis in these cells.

Dual challenges of infectious pancreatic necrosis virus and Vibrio carchariae in the grouper, Epinephelus sp

The grouper industry in Taiwan faces serious threats from various disease problems. The present study investigated dual challenges with infectious pancreatic necrosis virus (IPNV) and Vibrio carchariae in the grouper (Epinephelus sp.). The fish were infected with IPNV for 2 weeks prior to a secondary infection with the bacteria, or vice versa, by either immersion (10(3)-10(4) TCID50 IPNV per ml, 10(6)-10(7) colony forming units (CFU) Vibrio per ml) or by intraperitoneal injection (10(3)-10(4) TCID50 IPNV per g fish or 10(7) CFU Vibrio/g fish) challenges. Mass mortalities occurred in fish infected with IPNV for 2 weeks prior to the infection with the bacteria, or vice versa, in either immersion or intraperitoneal injection challenges. The bacterium could only survive in seawater or brackish water similar to that of cultured groupers.

Effect of heavy metal stressors and salinity shock on the susceptibility of grouper (Epinephelus sp.) to infectious pancreatic necrosis virus

In the present study, attempts were made to clarify the effect of heavy metal stressors and salinity shock on the disease susceptibility of grouper fry (Epinephelus sp.) to infectious pancreatic necrosis virus (IPNV) infection. Zinc, cadmium and copper (5 ppm ZnCl2, 3 ppm CdCl2 and 1 ppm CuCl2) were used to treat groupers before and after virus infection. Cumulative mortalities in the experimental groups were 96-100% within 42 days. Only 5-15% mortalities were observed in most of the groups that were exposed to either heavy metals or virus infection alone. Subsequently, virus was re-isolated from the experimentally infected groupers, and copper concentration was measured in fish that had been exposed to CuCl2. We also investigated the effect of salinity shock (i.e. an abrupt change of salinity level from 33 ppt to either 40 ppt or 20 ppt) on susceptibility of grouper to IPNV. Similar results were obtained, mortalities of groupers in the experimental groups reached 80-100%. The results of the present study suggest that an IPN virus with only low pathogenicity could cause high mortality in groupers when combined with environmental stress.

Dynamics of nontypical apoptotic morphological changes visualized by green fluorescent protein in living cells with infectious pancreatic necrosis virus infection

Morphologically, apoptotic cells are characterized by highly condensed membrane blebbing and formation of apoptotic bodies. Recently, we reported that apoptosis precedes necrosis in a fish cell line infected with infectious pancreatic necrosis virus (IPNV). In the present study, we tested the possibility that nontypical apoptosis is a component of IPNV-induced fish cell death. A variant type of green fluorescent protein (EGFP) was expressed in a fish cell line such that EGFP served as a protein marker for visualizing dynamic apoptotic cell morphological changes and for tracing membrane integrity changes during IPNV infection. Direct morphological changes were visualized by fluorescence microscopy by EGFP in living cells infected with IPNV. The nontypical apoptotic morphological change stage occurred during the pre-late stage (6 to 7 h postinfection). Nontypical apoptotic features, including highly condensed membrane blebbing, occurred during the middle apoptotic stage. At the pre-late apoptotic stage, membrane vesicles quickly formed, blebbed, and were finally pinched off from the cell membrane. At the same time, at this pre-late apoptotic stage, apoptotic cells formed unique small holes in their membranes that ranged from 0.39 to 0.78 micrometer according to examination by scanning electron microscopy and immunoelectron microscopy. Quantitation of the intra- and extracellular release of EGFP by CHSE-214-EGFP cells after IPNV infection was done by Western blotting and fluorometry. Membrane integrity was quickly lost during the late apoptotic stage (after 8 h postinfection), and morphological change and membrane integrity loss could be prevented and blocked by treatment with apoptosis inhibitors such as cycloheximide, genistein, and EDTA before IPNV infection. Together, these findings show the apoptotic features at the onset of pathology in host cells (early and middle apoptotic stages), followed secondarily by nontypical apoptosis (pre-late apoptotic stage) and then by postapoptotic necrosis (late apoptotic stage), of a fish cell line. Our results demonstrate that nontypical apoptosis is a component of IPNV-induced fish cell death.

Apoptosis precedes necrosis of fish cell line with infectious pancreatic necrosis virus infection

The current view of infectious pancreatic necrosis virus (IPNV) infection includes a necrotic process that relies primarily on the histological appearance of tissue after the degenerative process. We tested this view by examining the possibility that apoptosis is a component of double-stranded RNA virus (IPNV) that induces fish embryonic cell death. Four kinds of assays for apoptosis were used in analyzing IPNV-infected CHSE-214 cells: (1) assay with terminal deoxynucleotidyl transferase (TdT)-mediated end-labeling of DNA in nuclei of intact cells during virus infection, (2) assay for procoagulant activity, (3) assay for DNA ladders, and (4) electron microscopic assays for the ultrastructural changes in characteristic apoptotic cells. In all p.i. samples, both low and high m.o.i. groups contained apoptotic nuclei, according to TdT-mediated dUTP labeling of intact cells, but in control CHSE-214 cells, apoptotic nuclei were rare at all levels of incubation sampled by TdT-mediated dUTP labeling. Prenecrotic or postnecrotic cells were found to express phosphatidylserine on the surface by annexin V-FITC labeling, but normal cells did not. DNAs from both 4 h p.i. of high m.o.i. and 8 h p.i. of low m.o.i. were found to be cleaved into fragments indicative of preferential cleavage at internucleosomal sites. The IPNV-infected CHSE-214 cells were analyzed with an electron microscope and showed a pattern of ultrastructural change, indicating that apoptosis appears before pathological changes of necrosis, including condensed chromatin, fragmented nuclei, nuclei with chromatin marginations, and secondary necrosis from prenecrotic cells in IPNV-infected CHSE-214 cells. Together, these findings show that apoptosis precedes any detectable necrotic change in CHSE-214 cells that is currently viewed as necrosis. Thus, apoptosis characterizes the onset of pathology in host cells and is followed by necrotic processes.

Precore stop codon mutant in chronic hepatitis B virus infection in children: its relation to hepatitis B e seroconversion and maternal hepatitis B surface antigen

BACKGROUND/AIMS

The aims of this study were to investigate the significance of the precore stop codon mutant in the natural course of hepatitis B virus infection in children, and the influence of maternal transmission.

METHODS

Sequential sera from 80 hepatitis B virus carrier children both before and after e seroconversion during long-term follow-up were studied using the polymerase chain reaction-amplification created restriction site method. Direct sequencing of the precore region was performed in 89 sera from 32 of the 80 children.

RESULTS

The precore stop codon mutant coexisting with wild strain was found in 10% of children initially, and later in 25% of children before e seroconversion. After e seroconversion, wild type was still present in 75% and mutant in 39% of children at the end of follow-up. The mutant alone was present in 15% of anti-HBe positive children without concomitant aminotransferase elevation. Children with earlier emergence of this mutant tended to have higher peak aminotransferase levels. This mutant emerged less frequently in children of hepatitis B virus carrier mothers (37.5%) than in those of non-carrier mothers (65%) (p<0.05).

CONCLUSIONS

These observations suggest that this mutant is selected by host immune pressure, but is not an initiator in the loss of immune tolerance during childhood chronic hepatitis B virus infection.

Involvement of serine proteinase in infectious pancreatic necrosis virus capsid protein maturation and NS proteinase cleavage in CHSE-214 cells

An investigation of virus-specific protein maturation in infectious pancreatic necrosis virus (IPNV) infected Chinook salmon embryo cells (CHSE-214) was undertaken. The precursor protein (pVP2-1) of the major mature capsid protein (VP2) was processed sequentially from pVP2-1 to pVP2-2 and VP2. Experiments using serine proteinase inhibitors showed that the maturation of the VP2 was blocked in the pVP2-1 post-translational cleavage steps. A protinin, a potent proteinase inhibitor, at 800 μg ml(-1) blocked pVP2-2 to VP2 and the cleavage of VP4 (28 kDa) to VP4-1 (25 kDa). Therefore, our data showed that the maturation of the capsid protein (VP2) and cleavage of VP4 (NS proteinase) can be blocked by serine proteinase inhibitors.

Transvaginal ultrasound-guided aspiration in the treatment and follow-up of tubo-ovarian abscess: a report of two cases

Two cases of tubo-ovarian abscess are presented in this study; treatment and follow-up were undertaken by transvaginal ultrasound. Transvaginal ultrasound-guided aspiration with anti-microbial therapy may be a useful alternative for treatment of unruptured tubo-ovarian abscess.

Molecular relationships in infectious pancreatic necrosis virus

Infectious pancreatic necrosis virus (IPNV), a Birnaviridae with a double-stranded RNA genome of two segments, is an important aquatic pathogen. Previous characterizations of the RNA and polypeptide patterns of different IPNV isolates have uncovered a wide variety of electropherotypes. We used RNA fingerprinting analysis to study the quasispecies, heterogeneity, and rapid mutation characteristics of IPN viruses. Via cluster analysis of the RNA fingerprints, IPNV standard serotypes as well as T42G-, T24K- and T34G-related isolates were classified into 3 clusters corresponding to the AB, SP, and VR-299 serological types. The IPNV SP cluster represents a different evolutionary route from those of the AB and VR-299 clusters. The VR-299 clusters were separated into two groups, the T34G group were divided into two subgroups. The molecular relationships between these isolates can be correlated with the biological characteristics of these IPN viruses, for example, selective growth in EPC cells and adaptive replication at high temperatures.

Dual pathways for agonist-stimulated arachidonic acid release in pancreatic acini: roles in secretion

The present experiments were performed to determine pathways responsible for arachidonic acid release stimulated by cholecystokinin (CCK) and phorbol ester, 4 beta-phorbol 12-myristate 13-acetate (PMA), and the roles of pathways in the secretory response in dispersed acini from guinea pig pancreas. Both CCK-octapeptide (CCK-OP) and PMA increased intracellular arachidonic acid. To determine the source of released arachidonic acid, we measured the effects of PMA and CCK-OP on cellular 1,2-diacylglycerol and lysophosphatidylcholine (LPC) and of diglyceride lipase inhibitor RHC 80267 on [3H]arachidonic acid release. Both PMA and CCK-OP increased 1,2-diacylglycerol and LPC. RHC 80267 had no effect on LPC but inhibited the increase in [3H]arachidonic acid release with a concentration of CCK-OP that was maximal for enzyme secretion. The increase in [3H]arachidonic acid release with PMA or a supramaximal concentration of CCK-OP was not inhibited by RHC 80267. In parallel fashion, RHC 80267 inhibited amylase release caused by maximally effective concentrations of CCK-OP but not that caused by PMA or by supramaximally effective concentrations of CCK-OP. Arachidonic acid stimulated amylase release. Exogenous addition of phospholipase A2 caused increases in [3H]arachidonic acid release, LPC formation, and amylase release. The results indicate that there are at least two pathways responsible for the increase in free cellular arachidonic acid stimulated by pancreatic agonists. One is sequential action of phospholipase C and diglyceride lipase on phosphatidylinositol. The other is a phospholipase A action on phosphatidylcholine. The results also suggest a stimulatory role for both pathways in the secretory response.

Comparison of RNAs and polypeptides of infectious pancreatic necrosis virus isolates from eel and rainbow trout

Thirteen isolates of infectious pancreatic necrosis virus (IPNV) from eel and rainbow trout in Taiwan were compared with the selected serotypes AB, SP and VR-299 by PAGE analysis of their RNA genomes and early polypeptides. All the IPNV isolates from eels (1984 to 1986) from Lu Kang and Ping Tung, and from rainbow trout eggs and fry from Dan Sway (1985 to 1986) were most closely related to the AB serotype. However four rainbow trout isolates from Dan Sway (1984) had a similar RNA pattern to that of VR-299, whereas their early polypeptides were different, showing evidence of some mutations. Both RNA and polypeptide PAGE patterns were used to distinguish the isolates from known selected IPNV strains showing that this approach can be used for epizootiological studies.

Occurrence of different types of infectious hematopoietic necrosis virus in fish

The virion protein patterns of 71 isolates of infectious hematopoietic necrosis virus (IHNV) from the Pacific Northwest were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of [35S]-methionine-labeled virus. This analysis led to the classification of these virus isolates into four or more types. Type 1 virus was characterized by a nucleocapsid protein with an approximate molecular weight of 40,500. Type 2 and type 3 viruses have nucleocapsid proteins with molecular weights of 42,800 and 43,250, respectively. Type 2 virus was responsible for the recent epizootics of IHNV among fish in the lower Columbia River. The California IHNV isolates were type 3 with the exception of some of those isolated from fish at the Coleman Hatchery on the Sacramento River. These Coleman Hatchery isolates belonged to a type 4 virus group characterized by a larger glycoprotein of approximately 70,000 molecular weight. All other viruses examined had glycoproteins of 67,000 molecular weight. The "type 5" virus isolates were grouped together because they were not sufficiently distinct to warrant classification into a separate type. These findings have been useful in determining that a particular virus type is characteristic for a geographic area and will infect many different salmonid species in that area and the same type isolated from parental fish is responsible for the subsequent outbreak of the diseases in progeny.