Asian-Pacific clinical practice guidelines on the management of hepatitis B: a 2015 update

Worldwide, some 240 million people have chronic hepatitis B virus (HBV), with the highest rates of infection in Africa and Asia. Our understanding of the natural history of HBV infection and the potential for therapy of the resultant disease is continuously improving. New data have become available since the previous APASL guidelines for management of HBV infection were published in 2012. The objective of this manuscript is to update the recommendations for the optimal management of chronic HBV infection. The 2015 guidelines were developed by a panel of Asian experts chosen by the APASL. The clinical practice guidelines are based on evidence from existing publications or, if evidence was unavailable, on the experts' personal experience and opinion after deliberations. Manuscripts and abstracts of important meetings published through January 2015 have been evaluated. This guideline covers the full spectrum of care of patients infected with hepatitis B, including new terminology, natural history, screening, vaccination, counseling, diagnosis, assessment of the stage of liver disease, the indications, timing, choice and duration of single or combination of antiviral drugs, screening for HCC, management in special situations like childhood, pregnancy, coinfections, renal impairment and pre- and post-liver transplant, and policy guidelines. However, areas of uncertainty still exist, and clinicians, patients, and public health authorities must therefore continue to make choices on the basis of the evolving evidence. The final clinical practice guidelines and recommendations are presented here, along with the relevant background information.

Hepatitis B genotypes correlate with clinical outcomes in patients with chronic hepatitis B

BACKGROUND & AIMS

Six genotypes (A-F) of hepatitis B virus (HBV) have been identified; however, the genotype-related differences in the pathogenicity of HBV remain unknown. Therefore, we investigated the prevalence of HBV genotypes in Taiwan and the association between distinct genotypes and severity of liver disease in a cross-sectional study.

METHODS

Using a molecular method, HBV genotypes were determined in 100 asymptomatic carriers and in 170 patients with histologically verified chronic liver disease and hepatocellular carcinoma (HCC).

RESULTS

All genotypes except genotype E were identified in Taiwan, and genotypes B and C were predominant. Genotype C was prevalent in patients with cirrhosis and in those with HCC who were older than 50 years compared with age-matched asymptomatic carriers (60% vs. 23%, P < 0.001, and 41% vs. 15%, P = 0.005, respectively). Genotype B was significantly more common in patients with HCC aged less than 50 years compared with age-matched asymptomatic carriers (80% vs. 52%, P = 0.03). This predominance was more marked in younger patients with HCC (90% in those aged </=35 years), most of whom did not have cirrhosis.

CONCLUSIONS

Our data suggest that HBV genotype C is associated with more severe liver disease and genotype B may be associated with the development of HCC in young Taiwanese. However, additional large-scale longitudinal studies are needed to confirm the relationship of HBV genotypes to liver disease severity and clinical outcomes.

Inhibition of ICE family proteases by baculovirus antiapoptotic protein p35

The baculovirus antiapoptotic protein p35 inhibited the proteolytic activity of human interleukin-1 beta converting enzyme (ICE) and three of its homologs in enzymatic assays. Coexpression of p35 prevented the autoproteolytic activation of ICE from its precursor form and blocked ICE-induced apoptosis. Inhibition of enzymatic activity correlated with the cleavage of p35 and the formation of a stable ICE-p35 complex. The ability of p35 to block apoptosis in different pathways and in distantly related organisms suggests a central and conserved role for ICE-like proteases in the induction of apoptosis.

Biocompatibility of engineered nanoparticles for drug delivery

The rapid advancement of nanotechnology has raised the possibility of using engineered nanoparticles that interact within biological environments for treatment of diseases. Nanoparticles interacting with cells and the extracellular environment can trigger a sequence of biological effects. These effects largely depend on the dynamic physicochemical characteristics of nanoparticles, which determine the biocompatibility and efficacy of the intended outcomes. Understanding the mechanisms behind these different outcomes will allow prediction of the relationship between nanostructures and their interactions with the biological milieu. At present, almost no standard biocompatibility evaluation criteria have been established, in particular for nanoparticles used in drug delivery systems. Therefore, an appropriate safety guideline of nanoparticles on human health with assessable endpoints is needed. In this review, we discuss the data existing in the literature regarding biocompatibility of nanoparticles for drug delivery applications. We also review the various types of nanoparticles used in drug delivery systems while addressing new challenges and research directions. Presenting the aforementioned information will aid in getting one step closer to formulating compatibility criteria for biological systems under exposure to different nanoparticles.

Hepatitis B genotypes and the response to interferon therapy

BACKGROUND/AIMS

Possible pathogenic differences among hepatitis B virus (HBV) genotypes have been observed; however, the response to interferon therapy among HBV genotypes remains unknown. We therefore analyzed the efficacy of interferon alfa in the treatment of chronic hepatitis B patients with different HBV genotypes.

METHODS

Fifty-eight genotype B or C infected chronic hepatitis B patients who had been treated with interferon alfa-2b were retrospectively studied. The response to interferon was defined as normalization of serum aminotransferase level, loss of hepatitis B e antigen and HBV DNA 48 weeks post-treatment.

RESULTS

Baseline data of both groups of patients were comparable; however, genotype C patients had a higher serum aminotransferase level and a higher frequency of core promoter mutation. The response rate was 41% and 15% in genotype B and C patients, respectively (p=0.045). In those with higher serum aminotransferase levels, the response rate was 50% and 17%, respectively (p=0.025). Additionally, younger age and genotype B infection may predict a better response to interferon alfa.

CONCLUSIONS

HBV genotype C, compared to genotype B, is associated with a higher frequency of core promoter mutation, and a lower response rate to interferon alfa therapy.

p27(Kip1) links cell proliferation to morphogenesis in the developing organ of Corti

Strict control of cellular proliferation is required to shape the complex structures of the developing embryo. The organ of Corti, the auditory neuroepithelium of the inner ear in mammals, consists of two types of terminally differentiated mechanosensory hair cells and at least four types of supporting cells arrayed precisely along the length of the spiral cochlea. In mice, the progenitors of greater than 80% of both hair cells and supporting cells undergo their terminal division between embryonic day 13 (E13) and E14. As in humans, these cells persist in a non-proliferative state throughout the adult life of the animal. Here we report that the correct timing of cell cycle withdrawal in the developing organ of Corti requires p27(Kip1), a cyclin-dependent kinase inhibitor that functions as an inhibitor of cell cycle progression. p27(Kip1) expression is induced in the primordial organ of Corti between E12 and E14, correlating with the cessation of cell division of the progenitors of the hair cells and supporting cells. In wild-type animals, p27(Kip1) expression is downregulated during subsequent hair cell differentiation, but it persists at high levels in differentiated supporting cells of the mature organ of Corti. In mice with a targeted deletion of the p27(Kip1) gene, proliferation of the sensory cell progenitors continues after E14, leading to the appearance of supernumerary hair cells and supporting cells. In the absence of p27(Kip1), mitotically active cells are still observed in the organ of Corti of postnatal day 6 animals, suggesting that the persistence of p27(Kip1) expression in mature supporting cells may contribute to the maintenance of quiescence in this tissue and, possibly, to its inability to regenerate. Homozygous mutant mice are severely hearing impaired. Thus, p27(Kip1) provides a link between developmental control of cell proliferation and the morphological development of the inner ear.

High H2 uptake by alkali-doped carbon nanotubes under ambient pressure and moderate temperatures

Lithium- or potassium-doped carbon nanotubes can absorb approximately 20 or approximately 14 weight percent of hydrogen at moderate (200 degrees to 400 degrees C) or room temperatures, respectively, under ambient pressure. These values are greater than those of metal hydride and cryoadsorption systems. The hydrogen stored in the lithium- or potassium-doped carbon nanotubes can be released at higher temperatures, and the sorption-desorption cycle can be repeated with little decrease in the sorption capacity. The high hydrogen-uptake capacity of these systems may be derived from the special open-edged, layered structure of the carbon nanotubes made from methane, as well as the catalytic effect of alkali metals.

grim, a novel cell death gene in Drosophila

A genomic interval at 75C1,2 is required for programmed cell death in Drosophila. We identified a new activator of apoptosis, grim, which maps between two previously identified cell death genes in this region reaper (rpr) and head involution defective (hid). Expression of grim RNA coincided with the onset of programmed cell death at all stages of embryonic development, whereas ectopic induction of grim triggered extensive apoptosis in both transgenic animals and in cell culture. Cell killing by grim was blocked by coexpression of p35, a viral product that inactivates ICE-like proteases, and did not require the functions of rpr or hid. The predicted grim protein shares an amino-terminal motif in common with rpr. However, grim was sufficient to elicit apoptosis in at least one context, where rpr was not. The grim gene product might thus function in a parallel circuit of cell death signaling that ultimately activates a common set of downstream apoptotic effectors.

Multiple ubiquitin-conjugating enzymes participate in the in vivo degradation of the yeast MAT alpha 2 repressor

Attachment of ubiquitin to proteins is catalyzed by a family of ubiquitin-conjugating (UBC) enzymes. Although these enzymes are essential for many cellular processes; their molecular functions remain unclear because no physiological target has been identified for any of them. Here we show that four UBC proteins (UBC4, UBC5, UBC6, and UBC7) target the yeast MAT alpha 2 transcriptional regulator for intracellular degradation by two distinct ubiquitination pathways. UBC6 and UBC7 define one of the pathways and can physically associate. The UBC6/UBC7-containing complex targets the Deg1 degradation signal of alpha 2, a conclusion underscored by the finding that UBC6 is encoded by DOA2, a gene previously implicated in Deg1-mediated degradation. These data reveal an unexpected overlap in substrate specificity among diverse UBC enzymes and suggest a combinatorial mechanism of substrate selection in which UBC enzymes partition into multiple ubiquitination complexes.

Waiting list may be a nocebo condition in psychotherapy trials: a contribution from network meta-analysis

OBJECTIVE

Various control conditions have been employed in psychotherapy trials, but there is growing suspicion that they may lead to different effect size estimates. The present study aims to examine the differences among control conditions including waiting list (WL), no treatment (NT) and psychological placebo (PP).

METHOD

We comprehensively searched for all randomized controlled trials (RCTs) comparing cognitive-behaviour therapies (CBT) against various control conditions in the acute phase treatment of depression, and applied network meta-analysis (NMA) to combine all direct and indirect comparisons among the treatment and control arms.

RESULTS

We identified 49 RCTs (2730 participants) comparing WL, NT, PP and CBT. This network of evidence was consistent, and the effect size estimates for CBT were substantively different depending on the control condition. The odds ratio of response for NT over WL was statistically significant at 2.9 (95% CI: 1.3-5.7). However, the quality of evidence, including publication bias, was less than ideal and none of the preplanned sensitivity analyses limiting to high-quality studies could be conducted, while findings of significant differences did not persist in post hoc sensitivity analyses trying to adjust for publication bias.

CONCLUSION

There may be important differences in control conditions currently used in psychotherapy trials.

Autocatalytic subunit processing couples active site formation in the 20S proteasome to completion of assembly

The eukaryotic 20S proteasome is responsible for the degradation of many cellular proteins, but how it is assembled and how its distinct active sites are formed are not understood. Like other proteasome subunits, the yeast Doa3 protein is synthesized in precursor form. We show that the N-terminal propeptide is required for Doa3 incorporation into the proteasome and, remarkably, that the propeptide functions in trans, suggesting it serves a chaperone-like function in proteasome biogenesis. Propeptide processing is not required for proteasome assembly but is needed for maturation of a specific subset of active sites. The likely nucleophile for these sites is provided by the N-terminal threonine of mature Doa3. Additional data indicate that precursor processing is autocatalytic and requires association of the two halves of the proteasome particle, thereby preventing formation of proteolytic sites until the central hydrolytic chamber has been sealed off from the rest of the cell.

Transient exposure to HIV-1 Tat protein results in cytokine production in macrophages and astrocytes. A hit and run phenomenon

The pathological correlates of dementia due to human immunodeficiency virus (HIV) infection are glial cell activation and cytokine dysregulation. These findings occur in the setting of small numbers of productively infected cells within the brain. We determined whether exposure of susceptible cells to Tat protein of HIV could result in the production of select proinflammatory cytokines. In a dose-responsive manner, Tat induced interleukin (IL)-1beta production in monocytic cells, while astrocytic cells showed an increase in mRNA for IL-1beta, but had a translation block for IL-1beta protein production. Conversely, IL-6 protein and mRNA productions were strongly induced in astrocytic cells and minimally in monocytic cells. IL-1beta and IL-6 production were independent of tumor necrosis factor-alpha production. An exposure to Tat for a few minutes was sufficient for sustained releases of cytokines for several hours. This prolonged cytokine production is likely maintained by a positive feed back loop of Tat-induced nuclear factor kappaB activation and cytokine production that is independent of extracellular calcium. Thus a transient exposure may be sufficient to initiate a cascade of events resulting in cerebral dysfunction and a "hit and run" approach may be in effect. Hence cross-sectional measurement of viral load in the brain may not be a useful indicator of the role of viral products in the neuropathogenesis of HIV dementia.

Dark is a Drosophila homologue of Apaf-1/CED-4 and functions in an evolutionarily conserved death pathway

Here we identify a new gene, dark, which encodes a Drosophila homologue of mammalian Apaf-1 and Caenorhabditis elegans CED-4, cell-death proteins. Like Apaf-1, but in contrast to CED-4, Dark contains a carboxy-terminal WD-repeat domain necessary for interactions with the mitochondrial protein cytochrome c. Dark selectively associates with another protein involved in apoptosis, the fly apical caspase, Dredd. Dark-induced cell killing is suppressed by caspase-inhibitory peptides and by a dominant-negative mutant Dredd protein, and enhanced by removal of the WD domain. Loss-of-function mutations in dark attenuate programmed cell deaths during development, causing hyperplasia of the central nervous system, and other abnormalities including ectopic melanotic tumours and defective wings. Moreover, ectopic cell killing by the Drosophila cell-death activators, Reaper, Grim and Hid, is substantially suppressed in dark mutants. These findings establish dark as an important apoptosis effector in Drosophila and raise profound evolutionary considerations concerning the relationship between mitochondrial components and the apoptosis-promoting machinery.

Patterns of cognitive decline in presymptomatic Alzheimer disease: a prospective community study

BACKGROUND

Specific patterns of decline over time were evaluated across a spectrum of cognitive measures in presymptomatic Alzheimer disease (AD) within a community sample.

METHODS

A total of 551 individuals completed a battery of standard cognitive tests 3.5 and 1.5 years before outcome (clinical onset of AD vs continued nondemented status) within a prospective community-based study of AD. Test score changes in 68 cases (who subsequently developed symptomatic AD) and 483 controls (who remained nondemented) on each of 15 cognitive measures were transformed into z scores adjusted for age, sex, and education. A case-control rate ratio of the proportions of individuals who showed "cognitive decline" on each test was calculated, representing the relative magnitude of cognitive decline on each test in presymptomatic AD compared with normal aging.

RESULTS

Declines in Trail-Making Tests A and B and Word List delayed recognition of originals and third immediate learning trial had the highest rate ratios, larger than 3.0 (P<.01). These were followed by Word List delayed recognition of foils and delayed recall, Consortium to Establish a Registry for Alzheimer's Disease Praxis, Clock Drawing, the Boston Naming Test, and Orientation, with rate ratios between 1.7 and 3.0 (P<.05).

CONCLUSIONS

Memory and executive dysfunction showed the greatest decline over time in individuals who would clinically manifest AD 1.5 years later. These findings might help us understand the underlying evolution of the early neurodegenerative process. They highlight the importance of executive dysfunction early in the disease process and might facilitate early detection of AD.

Structure and replication of the genome of the hepatitis delta virus

The hepatitis delta virus can be found in the serum and liver of some hepatitis B virus patients. We now report that the RNA genome of serum-derived delta virus is single-stranded and circular. Livers of infected chimpanzees or woodchucks contained as many as 300,000 copies of genomic strand RNA per average cell, and at least some of this RNA had a circular conformation. Also present in the livers were RNA species complementary to the virion RNA. The genomic RNA was 5-22 times more abundant than this antigenomic strand. Some of the antigenomic RNA was complexed with genomic RNA, as evidenced by the fact that at least 34% of the antigenomic RNA was resistant to digestion with either RNase A in 0.3 M NaCl or S1 nuclease. Some of the antigenomic RNA was in a circular conformation. These and other findings showed that the structure and replication of hepatitis delta virus are in many ways similar to those of the previously described plant viroids, virusoids, and satellite RNAs.

The large form of hepatitis delta antigen is crucial for assembly of hepatitis delta virus

The virions of hepatitis delta virus (HDV) contain two species of HDV-specific protein, a large and a small form of hepatitis delta antigen (HDAg). We examined the role of individual HDAgs in virion assembly in cotransfection experiments. First, we constructed a replication-competent HDV mutant expressing only the small HDAg. When cotransfected with a plasmid expressing hepatitis B virus surface antigens to the HuH-7 cells, the mutant did not produce HDV virions, whereas the wild-type HDV clone did. Therefore, though the small HDAg is important for viral replication and is incorporated into the virus, the small-form delta antigen by itself is insufficient for virion formation. When the system was co-transfected with an additional plasmid providing the large HDAg, the HDV virion was then recovered. There was also evidence suggesting that the large HDAg could be copackaged into the HBsAg particles, without the presence of the HDV genome and the small HDAg. The results indicate a crucial role of the large HDAg in HDV assembly.

Epidermal growth factor receptor-mediated cell motility: phospholipase C activity is required, but mitogen-activated protein kinase activity is not sufficient for induced cell movement

We recently have demonstrated that EGF receptor (EGFR)-induced cell motility requires receptor kinase activity and autophosphorylation (P. Chen, K. Gupta, and A. Wells. 1994. J. Cell Biol. 124:547-555). This suggests that the immediate downstream effector molecule contains a src homology-2 domain. Phospholipase C gamma (PLC gamma) is among the candidate transducers of this signal because of its potential roles in modulating cytoskeletal dynamics. We utilized signaling-restricted EGFR mutants expressed in receptor devoid NR6 cells to determine if PLC activation is necessary for EGFR-mediated cell movement. Exposure to EGF (25 nM) augmented PLC activity in all five EGFR mutant cell lines which also responded by increased cell movement. Basal phosphoinositide turnover was not affected by EGF in the lines which do not present the enhanced motility response. The correlation between EGFR-mediated cell motility and PLC activity suggested, but did not prove, a causal link. A specific inhibitor of PLC, U73122 (1 microM) diminished both the EGF-induced motility and PLC responses, while its inactive analogue U73343 had no effect on these responses. Both the PLC and motility responses were decreased by expression of a dominant-negative PLC gamma-1 fragment in EGF-responsive infectant lines. Lastly, anti-sense oligonucleotides (20 microM) to PLC gamma-1 reduced both responses in NR6 cells expressing wild-type EGFR. These findings strongly support PLC gamma as the immediate post receptor effector in this motogenic pathway. We have demonstrated previously that EGFR-mediated cell motility and mitogenic signaling pathways are separable. The point of divergence is undefined. All kinase-active EGFR mutants induced the mitogenic response while only those which are autophosphorylated induced PLC activity. U73122 did not affect EGF-induced thymidine incorporation in these motility-responsive infectant cell lines. In addition, the dominant-negative PLC gamma-1 fragment did not diminish EGF-induced thymidine incorporation. All kinase active EGFR stimulated mitogen-activated protein (MAP) kinase activity, regardless of whether the receptors induced cell movement; this EGF-induced MAP kinase activity was not affected by U73122 at concentrations that depressed the motility response. Thus, the signaling pathways which lead to motility and cell proliferation diverge at the immediate post-receptor stage, and we suggest that this is accomplished by differential activation of effector molecules.

Mechanisms of GDF-5 action during skeletal development

Mutations in GDF-5, a member of the TGF-beta superfamily, result in the autosomal recessive syndromes brachypod (bp) in mice and Hunter-Thompson and Grebe-type chondrodysplasias in humans. These syndromes are all characterised by the shortening of the appendicular skeleton and loss or abnormal development of some joints. To investigate how GDF-5 controls skeletogenesis, we overexpressed GDF-5 during chick limb development using the retrovirus, RCASBP. This resulted in up to a 37.5% increase in length of the skeletal elements, which was predominantly due to an increase in the number of chondrocytes. By injecting virus at different stages of development, we show that GDF-5 can increase both the size of the early cartilage condensation and the later developing skeletal element. Using in vitro micromass cultures as a model system to study the early steps of chondrogenesis, we show that GDF-5 increases chondrogenesis in a dose-dependent manner. We did not detect changes in proliferation. However, cell suspension cultures showed that GDF-5 might act at these stages by increasing cell adhesion, a critical determinant of early chondrogenesis. In contrast, pulse labelling experiments of GDF-5-infected limbs showed that at later stages of skeletal development GDF-5 can increase proliferation of chondrocytes. Thus, here we show two mechanisms of how GDF-5 may control different stages of skeletogenesis. Finally, our data show that levels of GDF-5 expression/activity are important in controlling the size of skeletal elements and provides a possible explanation for the variation in the severity of skeletal defects resulting from mutations in GDF-5.

Distinct phenotypes distinguish the molecular classes of Angelman syndrome

BACKGROUND

Angelman syndrome (AS) is a severe neurobehavioural disorder caused by defects in the maternally derived imprinted domain located on 15q11-q13. Most patients acquire AS by one of five mechanisms: (1) a large interstitial deletion of 15q11-q13; (2) paternal uniparental disomy (UPD) of chromosome 15; (3) an imprinting defect (ID); (4) a mutation in the E3 ubiquitin protein ligase gene (UBE3A); or (5) unidentified mechanism(s). All classical patients from these classes exhibit four cardinal features, including severe developmental delay and/or mental retardation, profound speech impairment, a movement and balance disorder, and AS specific behaviour typified by an easily excitable personality with an inappropriately happy affect. In addition, patients can display other characteristics, including microcephaly, hypopigmentation, and seizures.

METHODS

We restricted the present study to 104 patients (93 families) with a classical AS phenotype. All of our patients were evaluated for 22 clinical variables including growth parameters, acquisition of motor skills, and history of seizures. In addition, molecular and cytogenetic analyses were used to assign a molecular class (I-V) to each patient for genotype-phenotype correlations.

RESULTS

In our patient repository, 22% of our families had normal DNA methylation analyses along 15q11-q13. Of these, 44% of sporadic patients had mutations within UBE3A, the largest percentage found to date. Our data indicate that the five molecular classes can be divided into four phenotypic groups: deletions, UPD and ID patients, UBE3A mutation patients, and subjects with unknown aetiology. Deletion patients are the most severely affected, while UPD and ID patients are the least. Differences in body mass index, head circumference, and seizure activity are the most pronounced among the classes.

CONCLUSIONS

Clinically, we were unable to distinguish between UPD and ID patients, suggesting that 15q11-q13 contains the only significant maternally expressed imprinted genes on chromosome 15.

Hepatitis C virus infection in an area hyperendemic for hepatitis B and chronic liver disease: the Taiwan experience

To assess the contribution of hepatitis C virus (HCV) in liver disease in Taiwan, antibody to HCV (anti-HCV) was studied by radioimmunoassay in 392 patients with chronic liver disease and in 440 healthy adults and 444 subjects at risk. The anti-HCV prevalence was 0.95% in 420 volunteer blood donors, 90% in 100 hemophiliacs, and 81% in 58 parenteral drug abusers. Anti-HCV was present in 6 (7.7%) of 78 hepatitis B surface antigen (HBsAg)-positive and 28 (65%) of 43 HBsAg-negative patients with chronic hepatitis, 3 (10%) of 31 HBsAg-positive and 13 (43%) of 30 HBsAg-negative cirrhotics, and 7 (17%) of 42 HBsAg-positive and 15 (63%) of 24 HBsAg-negative patients with hepatocellular carcinoma (HCC). An outbreak of non-A, non-B hepatitis revealed 18% of 57 patients to be positive for anti-HCV, and in 29 patients with posttransfusion hepatitis prospectively followed, 7 (24%) developed anti-HCV. Thus, HCV infection appears to play a relatively minor role in HBsAg-positive liver disease in Taiwan but is strongly associated with HBsAg-negative chronic liver disease and HCC. The infection is extremely common in hemophiliacs and parenteral drug abusers.

Cognitive tests that best discriminate between presymptomatic AD and those who remain nondemented

OBJECTIVE

To identify the most accurate cognitive measures in discriminating between individuals with presymptomatic AD and individuals who remained nondemented.

METHODS

During a 10-year prospective community study, 120 nondemented subjects completed a battery of standard cognitive tests and clinically manifested AD 1.5 years later. Performance on each of 16 cognitive tests was compared between these 120 presymptomatic cases and 483 controls who remained nondemented over the 10-year follow-up period. The area under the receiver operating characteristic (AUC) curve for each test was used to measure its accuracy of discrimination between cases and controls.

RESULTS

Among the 16 neuropsychological tests, Word List Delayed Recall discriminated best between cases and controls (AUC = 0.806), followed by the Word List 3rd Learning Trial (0.787), Word List 1st Learning Trial (0.774), and Trail-making Test B (0.773), compared to the Mini-Mental State Examination (MMSE) (0.726). Both Word List Delayed Recall and Word List 3rd Learning Trial were significantly more accurate than the MMSE. The combination of Word List Delayed Recall and Trail-making Test B comprised the optimal set of cognitive measures, with the highest AUC (0.852).

CONCLUSION

Measures of delayed recall and executive functions were the best discriminators between those who would manifest AD 1.5 years later and those who would remain nondemented. These findings are relevant for the early detection of AD and, therefore, for prevention and early intervention trials. Executive dysfunction may be a subtle manifestation of incipient AD, along with memory dysfunction.

Acute exacerbations of chronic type B hepatitis are accompanied by increased T cell responses to hepatitis B core and e antigens. Implications for hepatitis B e antigen seroconversion

T cell proliferative responses to hepatitis B virus-encoded envelope antigen (S + preS2 + preS1), recombinant core antigen (HBcAg), and natural hepatitis B e antigen (HBeAg) were examined in 22 HBeAg-positive patients with chronic type B hepatitis and 17 healthy hepatitis B surface antigen (HBsAg) carriers. The results showed that HBeAg-positive patients had (a) higher levels of T cell responses to HBcAg/HBeAg than those of healthy HBsAg carriers (P less than 0.001 and P less than 0.01, respectively); (b) a further increase in these T cell responses during acute exacerbations (P less than 0.05 and P less than 0.05, respectively); (c) subsidence in the T cell responses to HBcAg/HBeAg after recovery from acute exacerbations and HBeAg seroconversion, whereas the responses would persist at high levels if the patients did not enter a clinical remission; and (d) low levels of T cell responses to S + preS2 + preS1 either before or after HBeAg seroconversion. The appearance of increasing T cell responses to HBcAg/HBeAg usually occurred in the early phase of acute exacerbations. These findings imply that HBcAg/HBeAg-specific T cells play an important role in the exacerbations of chronic hepatitis B and in HBeAg seroconversion. HBcAg/HBeAg-specific precursor T cell frequencies were serially studied in selected cases by limiting dilution assay. Elevation (two- to fourfold) of HBcAg/HBeAg-specific precursor T cell frequencies contributed to the increase of HBcAg/HBeAg-specific T cell proliferation during acute exacerbations.

The temporal relationship between depressive symptoms and dementia: a community-based prospective study

BACKGROUND

The temporal relationship between the appearance of depressive symptoms and the clinical onset of dementia and Alzheimer disease was evaluated in a community sample.

METHODS

An original sample of 1366 subjects aged 65 years or older, selected randomly from a rural Pennsylvania community, was cognitively screened at study entry and every 2 years thereafter. A subset of 954 survivors of this cohort without dementia was screened for depressive symptoms at the second and subsequent data-collection waves. A "depression cluster" was identified by the presence of 5 or more depressive symptoms, including depressed mood, at the time of screening. Cognitively impaired subjects and a sample of unimpaired controls underwent standardized clinical evaluation to determine the presence of incident dementia (by DSM-III-R criteria) and probable or possible Alzheimer disease (by criteria of the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association) and to estimate the clinical onset of dementia symptoms.

RESULTS

A highly increased probability of the depression cluster developing existed among subjects following the onset of dementia (15.4% [6/39]) and Alzheimer disease (17.6% [6/34]) compared with subjects without dementia (3.2% [23/712]). The odds ratios, after adjustment for age, sex, education level, and self reported memory loss, for the development of depression were 6.5 (95% confidence interval, 2.2-19.1) in subjects with Alzheimer disease and 5.2 (95% confidence interval, 1.8-15.2) in subjects with overall dementia. Depressive symptoms did not confer a significantly increased relative risk of dementia (1.27; 95% confidence interval, 0.55-2.93) or Alzheimer disease (1.28; 95% confidence interval, 0.51-3.20).

CONCLUSION

Depressive symptoms appeared to be early manifestations, rather than predictors, of Alzheimer disease in this community sample.

Cellular pharmacology and molecular biology of the trabecular meshwork inducible glucocorticoid response gene product

Studies of the effects of glucocorticoid (GC) and oxidative stress stimuli in differentiated cultures of human trabecular meshwork (HTM) cells have provided the rationale for our studies of a major new gene termed TIGR (trabecular meshwork inducible GC response). The TIGR clone was isolated by differential library screening using selection criteria based on the induction pattern of a new protein/glycoprotein found in HTM cultures after prolonged but not brief exposure to GCs. This GC induction pattern matched the time course and dose response required for intraocular pressure elevation in patients receiving corticosteroids. The very large, progressive induction of TIGR combined with specific structural features of its cDNA suggested that TIGR should be considered a candidate gene for outflow obstruction in glaucoma. Among the properties of TIGR cDNA were a signal sequence for secretion, several structural features for interactions with glycosaminoglycans and other glycoproteins and putative sites for cell surface interactions. In addition, the leucine zippers in the structure were related to TIGR-TIGR oligomerization that was shown to occur with native and recombinant TIGR protein. The verification that TIGR was a major stress response protein in HTM cells following hydrogen peroxide (or phorbol esters) exposure provided a potential link between GC and oxidative mechanisms thought to be involved in glaucoma pathogenesis. Pharmacological evaluation showed that basic fibroblast growth factory and transforming growth factor beta decreased the GC induction of TIGR, and certain nonsteroidal anti-inflammatory drugs protected against both GC- and oxidation-induced stress responses in HTM cells. Our recent studies of TIGR's genomic structure have shown motifs in the promoter region that suggest a basis by which multiple hormonal/environmental stimuli can regulate TIGR production and by which putative genetic alterations could lead to an overexpression of the protein. Further application of cell biology/biochemistry, molecular biology, genetic and histological approaches will be helpful in understanding the role of TIGR in different glaucoma syndromes.

Gene structure and properties of TIGR, an olfactomedin-related glycoprotein cloned from glucocorticoid-induced trabecular meshwork cells

Expression of the trabecular meshwork inducible glucocorticoid response (TIGR) gene progressively increases from barely detectable levels to greater than 2% of total cellular mRNA over 10 days exposure of trabecular meshwork (TM) cells to dexamethasone. Cycloheximide blocked most of the TIGR mRNA induction, suggesting a requirement for ongoing protein synthesis. The genomic structure of TIGR (approximately 20 kilobases) consists of 3 exons, and a 5-kilobase promoter region that contains 13 predicted hormone response elements, including several glucocorticoid regulatory elements, and other potentially important regulatory motifs. TIGR cDNA encodes an olfactomedin-related glycoprotein of 504 amino acids with motifs for N- and O-linked glycosylation, glycosaminoglycan initiation, hyaluronic acid binding, and leucine zippers. Recombinant TIGR (rTIGR) showed oligomerization and specific binding to TM cells. Anti-rTIGR antibody detected multiple translational/post-translational forms of TIGR produced by the cells (including secreted 66 kDa/55 kDa glycoproteins/proteins in the media and 55 kDa cellular proteins), whereas Northern blot showed a single mRNA species. The findings suggest potential mechanisms by which TIGR could obstruct the aqueous humor fluid flow and participate in the pathogenesis of glaucoma.