481 research outputs found
Subgenomic replicons of the flavivirus Kunjin: construction and applications
Several Kunjin virus (KUN) subgenomic replicons containing large deletions in the structural region (C-prM-E) and in the 3' untranslated region (3'UTR) of the genome have been constructed. Replicon RNA Delta ME with 1,987 nucleotides deleted (from nucleotide 417 [in codon 108] in the C gene to nucleotide 2403 near the carboxy terminus of the E gene, inclusive) and replicon RNA C20rep with 2,247 nucleotides deleted (from nucleotide 157 [in codon 20] in C to nucleotide 2403) replicated efficiently in electroporated BHK21 cells. A further deletion from C20rep of 53 nucleotides, reducing the coding sequence in core protein to two codons (C2rep RNA), resulted in abolishment of RNA replication. Replicon Delta ME/76 with a deletion of 76 nucleotides in the 3'UTR of Delta ME RNA (nucleotides 10423 to 10498) replicated efficiently, whereas replicon Delta ME/352 with a larger deletion of 352 nucleotides (nucleotides 10423 to 10774), including two conserved sequences RCS3 and CS3, was significantly inhibited in RNA replication. To explore the possibility of using a reporter gene assay to monitor synthesis of the positive strand and the negative strand of KUN RNA, we inserted a chloramphenicol acetyltransferase (CAT) gene into the 3'UTR of Delta ME/76 RNA under control of the internal ribosomal entry site (IRES) of encephalomyelocarditis virus RNA in both plus (Delta ME/76CAT[+])- and minus (Delta ME/76CAT[-])-sense orientations. Although insertion of the IRES-CAT cassette in the plus-sense orientation resulted in a significant (10- to 20-fold) reduction of RNA replication compared to that of the parental Delta ME/76 RNA, CAT expression was readily detected in electroporated BHK cells. No CAT expression was detected after electroporation of RNA containing the IRES-CAT cassette inserted in the minus-sense orientation despite its apparently more efficient replication (similar to that of Delta ME/76 RNA); this result indicated that KUN negative-strand RNA was probably not released from its template after synthesis. Replacement of the CAT gene in the Delta ME/76CAT(+) RNA with the neomycin gene (Neo) enabled selection and recovery of a BHK cell culture in which the majority of cells were continuously expressing the replicon RNA for 41 days (nine passages) without apparent cytopathic effect. The constructed KUN replicons should provide valuable tools to study flavivirus RNA replication as well as providing possible vectors for a long-lasting and noncytopathic RNA virus expression system
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Phenotypic heterogeneity and genetic modification of P102L inherited prion disease in an international series
The largest kindred with inherited prion disease P102L, historically Gerstmann-Sträussler-Scheinker syndrome, originates from central England, with émigrés now resident in various parts of the English-speaking world. We have collected data from 84 patients in the large UK kindred and numerous small unrelated pedigrees to investigate phenotypic heterogeneity and modifying factors. This collection represents by far the largest series of P102L patients so far reported. Microsatellite and genealogical analyses of eight separate European kindreds support multiple distinct mutational events at a cytosine-phosphate diester-guanidine dinucleotide mutation hot spot. All of the smaller P102L kindreds were linked to polymorphic human prion protein gene codon 129M and were not connected by genealogy or microsatellite haplotype background to the large kindred or each other. While many present with classical Gerstmann-Sträussler-Scheinker syndrome, a slowly progressive cerebellar ataxia with later onset cognitive impairment, there is remarkable heterogeneity. A subset of patients present with prominent cognitive and psychiatric features and some have met diagnostic criteria for sporadic Creutzfeldt-Jakob disease. We show that polymorphic human prion protein gene codon 129 modifies age at onset: the earliest eight clinical onsets were all MM homozygotes and overall age at onset was 7 years earlier for MM compared with MV heterozygotes (P = 0.02). Unexpectedly, apolipoprotein E4 carriers have a delayed age of onset by 10 years (P = 0.02). We found a preponderance of female patients compared with males (54 females versus 30 males, P = 0.01), which probably relates to ascertainment bias. However, these modifiers had no impact on a semi-quantitative pathological phenotype in 10 autopsied patients. These data allow an appreciation of the range of clinical phenotype, modern imaging and molecular investigation and should inform genetic counselling of at-risk individuals, with the identification of two genetic modifiers
High-K volcanism in the Afyon region, western Turkey: from Si-oversaturated to Si-undersaturated volcanism
Volcanic rocks of the Afyon province (eastern
part of western Anatolia) make up a multistage potassic and ultrapotassic alkaline series dated from 14 to 12 Ma. The early-stage Si-oversaturated volcanic rocks around the Afyon city and further southward are trachyandesitic volcanic activity (14.23 ± 0.09 Ma). Late-stage Si-undersaturated volcanism in the southernmost part of the Afyon volcanic province took place in three episodes inferred from their stratigraphic relationships and ages. Melilite–
leucitites (11.50 ± 0.03 Ma), spotted rachyandesites, tephryphonolites and lamproites (11.91 ± 0.13 Ma) formed in the first episode; trachyandesites in the second episode and finally phonotephrites, phonolite, basaltic trachyandesites and nosean-bearing trachyandesites during the last episode.
The parameter Q [normative q-(ne + lc + kls + ol)] of western Anatolia volcanism clearly decreased southward with time becoming zero in the time interval 10–15 Ma.
The magmatism experienced a sudden change in the extent of Si saturation after 14 Ma, during late-stage volcanic activity of Afyon volcanic province at around 12 Ma, though there was some coexistence of Si-oversaturated and Si-undersaturated magmas during the whole life of Afyon volcanic province
Anatomy of a microearthquake sequence on an active normal fault
The analysis of similar earthquakes, such as events in a seismic sequence, is an effective tool with which to monitor and study source processes and to understand the mechanical and dynamic states of active fault systems. We are observing seismicity that is primarily concentrated in very limited regions along the 1980 Irpinia earthquake fault zone in Southern Italy, which is a complex system characterised by extensional stress regime. These zones of weakness produce repeated earthquakes and swarm-like microearthquake sequences, which are concentrated in a few specific zones of the fault system. In this study, we focused on a sequence that occurred along the main fault segment of the 1980 Irpinia earthquake to understand its characteristics and its relation to the loading-unloading mechanisms of the fault system
Early-onset amyloid deposition and cognitive deficits in transgenic mice expressing a double mutant form of APP695
An investigation of factors associated with the health and well-being of HIV-infected or HIV-affected older people in rural South Africa
BackgroundDespite the severe impact of HIV in sub-Saharan Africa, the health of older people aged 50+ is often overlooked owing to the dearth of data on the direct and indirect effects of HIV on older people's health status and well-being. The aim of this study was to examine correlates of health and well-being of HIV-infected older people relative to HIV-affected people in rural South Africa, defined as participants with an HIV-infected or death of an adult child due to HIV-related cause. MethodsData were collected within the Africa Centre surveillance area using instruments adapted from the World Health Organization (WHO) Study on global AGEing and adult health (SAGE). A stratified random sample of 422 people aged 50+ participated. We compared the health correlates of HIV-infected to HIV-affected participants using ordered logistic regressions. Health status was measured using three instruments: disability index, quality of life and composite health score. ResultsMedian age of the sample was 60 years (range 50-94). Women HIV-infected (aOR 0.15, 95% confidence interval (CI) 0.08-0.29) and HIV-affected (aOR 0.20, 95% CI 0.08-0.50), were significantly less likely than men to be in good functional ability. Women's adjusted odds of being in good overall health state were similarly lower than men's; while income and household wealth status were stronger correlates of quality of life. HIV-infected participants reported better functional ability, quality of life and overall health state than HIV-affected participants. Discussion and Conclusions The enhanced healthcare received as part of anti-retroviral treatment as well as the considerable resources devoted to HIV care appear to benefit the overall well-being of HIV-infected older people; whereas similar resources have not been devoted to the general health needs of HIV uninfected older people. Given increasing numbers of older people, policy and programme interventions are urgently needed to holistically meet the health and well-being needs of older people beyond the HIV-related care system. <br/
A reassessment of the early archaeological record at Leang Burung 2, a Late Pleistocene rock-shelter site on the Indonesian island of Sulawesi
This paper presents a reassessment of the archaeological record at Leang Burung 2, a key early human occupation site in the Late Pleistocene of Southeast Asia. Excavated originally by Ian Glover in 1975, this limestone rock-shelter in the Maros karsts of Sulawesi, Indonesia, has long held significance in our understanding of early human dispersals into \u27Wallacea\u27, the vast zone of oceanic islands between continental Asia and Australia. We present new stratigraphic information and dating evidence from Leang Burung 2 collected during the course of our excavations at this site in 2007 and 2011-13. Our findings suggest that the classic Late Pleistocene modern human occupation sequence identified previously at Leang Burung 2, and proposed to span around 31,000 to 19,000 conventional 14C years BP (~35-24 ka cal BP), may actually represent an amalgam of reworked archaeological materials. Sources for cultural materials of mixed ages comprise breccias from the rear wall of the rock-shelter-remnants of older, eroded deposits dated to 35-23 ka cal BP-and cultural remains of early Holocene antiquity. Below the upper levels affected by the mass loss of Late Pleistocene deposits, our deep-trench excavations uncovered evidence for an earlier hominin presence at the site. These findings include fossils of now-extinct proboscideans and other \u27megafauna\u27 in stratified context, as well as a cobble-based stone artifact technology comparable to that produced by late Middle Pleistocene hominins elsewhere on Sulawesi
West Nile virus encodes a microRNA-like small RNA in the 3′ untranslated region which up-regulates GATA4 mRNA and facilitates virus replication in mosquito cells
West Nile virus (WNV) belongs to a group of medically important single-stranded, positive-sense RNA viruses causing deadly disease outbreaks around the world. The 3′ untranslated region (3′-UTR) of the flavivirus genome, in particular the terminal 3′ stem–loop (3′SL) fulfils multiple functions in virus replication and virus–host interactions. Using the Kunjin strain of WNV (WNVKUN), we detected a virally encoded small RNA, named KUN-miR-1, derived from 3′SL. Transcription of WNVKUN pre-miRNA (3′SL) in mosquito cells either from plasmid or Semliki Forest virus (SFV) RNA replicon resulted in the production of mature KUN-miR-1. Silencing of Dicer-1 but not Dicer-2 led to a reduction in the miRNA levels. Further, when a synthetic inhibitor of KUN-miR-1 was transfected into mosquito cells, replication of viral RNA was significantly reduced. Using cloning and bioinformatics approaches, we identified the cellular GATA4 mRNA as a target for KUN-miR-1. KUN-miR-1 produced in mosquito cells during virus infection or from plasmid DNA, SFV RNA replicon or mature miRNA duplex increased accumulation of GATA4 mRNA. Depletion of GATA4 mRNA by RNA silencing led to a significant reduction in virus RNA replication while a KUN-miR-1 RNA mimic enhanced replication of a mutant WNVKUN virus producing reduced amounts of KUN-miR-1, suggesting that GATA4-induction via KUN-miR-1 plays an important role in virus replication
A Copine family member, Cpne8, is a candidate quantitative trait gene for prion disease incubation time in mouse
Prion disease incubation time in mice is determined by many factors including genetic background. The prion gene itself plays a major role in incubation time; however, other genes are also known to be important. Whilst quantitative trait loci (QTL) studies have identified multiple loci across the genome, these regions are often large, and with the exception of Hectd2 on Mmu19, no quantitative trait genes or nucleotides for prion disease incubation time have been demonstrated. In this study, we use the Northport heterogeneous stock of mice to reduce the size of a previously identified QTL on Mmu15 from approximately 25 to 1.2 cM. We further characterised the genes in this region and identify Cpne8, a member of the copine family, as the most promising candidate gene. We also show that Cpne8 mRNA is upregulated at the terminal stage of disease, supporting a role in prion disease. Applying these techniques to other loci will facilitate the identification of key pathways in prion disease pathogenesis
Efficacy of manipulation for non-specific neck pain of recent onset: design of a randomised controlled trial
BACKGROUND: Manipulation is a common treatment for non-specific neck pain. Neck manipulation, unlike gentler forms of manual therapy such as mobilisation, is associated with a small risk of serious neurovascular injury and can result in stroke or death. It is thought however, that neck manipulation provides better results than mobilisation where clinically indicated. There is long standing and vigorous debate both within and between the professions that use neck manipulation as well as the wider scientific community as to whether neck manipulation potentially does more harm than good. The primary aim of this study is to determine whether neck manipulation provides more rapid resolution of an episode of neck pain than mobilisation. METHODS/DESIGN: 182 participants with acute and sub-acute neck pain will be recruited from physiotherapy, chiropractic and osteopathy practices in Sydney, Australia. Participants will be randomly allocated to treatment with either manipulation or mobilisation. Randomisation will occur after the treating practitioner decides that manipulation is an appropriate treatment for the individual participant. Both groups will receive at least 4 treatments over 2 weeks. The primary outcome is number of days taken to recover from the episode of neck pain. Cox regression will be used to compare survival curves for time to recovery for the manipulation and mobilisation treatment groups. DISCUSSION: This paper presents the rationale and design of a randomised controlled trial to compare the effectiveness of neck manipulation and neck mobilisation for acute and subacute neck pain
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