21 research outputs found
Inducible nitric oxide synthase (NOS2) promoter CCTTT repeat polymorphism: relationship to in vivo nitric oxide production/NOS activity in an asymptomatic malaria-endemic population
Journal ArticlePolymorphisms in the inducible nitric oxide synthase gene (NOS2) promoter have been associated with clinical outcome from malaria. These include a CCTTT repeat (CCTTTn) 2.5 kilobases upstream from the NOS2 transcription start site, and two single nucleotide substitutions: G-->C at position -954 (G-954C), and C-->T at position -1173 (C-1173T). Although hypothesized to influence NO production in vivo, the functional relevance of (CCTTT)n and G-954C is uncertain because disease association studies have yielded inconsistent results. This study found no association between CCTTT repeat number and levels of plasma NO metabolites or peripheral blood mononuclear cell NOS activity in a cohort of asymptomatic malaria-exposed coastal Papua New Guineans 1-60 years old. This suggests that (CCTTT)n does not independently influence NOS2 transcription in vivo. Neither the G-954C nor the C-1173T polymorphisms were identified in this population, indicating the variability and complexity of selection for NOS2 promoter polymorphisms in different malaria-endemic populations
A study of the TNF/LTA/LTB locus and susceptibility to severe malaria in highland papuan children and adults
Background: Severe malaria (SM) syndromes caused by Plasmodium falciparum infection result in major morbidity and mortality each year. However, only a fraction of P. falciparum infections develop into SM, implicating host genetic factors as important determinants of disease outcome. Previous studies indicate that tumour necrosis factor (TNF) and lymphotoxin alpha (LT alpha) may be important for the development of cerebral malaria (CM) and other SM syndromes
Deep Sequencing for the Detection of Virus-Like Sequences in the Brains of Patients with Multiple Sclerosis: Detection of GBV-C in Human Brain
<div><p>Multiple sclerosis (MS) is a demyelinating disease of unknown origin that affects the central nervous system of an estimated 400,000 Americans. GBV-C or hepatitis G is a flavivirus that is found in the serum of 1–2% of blood donors. It was originally associated with hepatitis, but is now believed to be a relatively non-pathogenic lymphotropic virus. Fifty frozen specimens from the brains of deceased persons affected by MS were obtained along with 15 normal control brain specimens. RNA was extracted and ribosomal RNAs were depleted before sequencing on the Illumina GAII. These 36 bp reads were compared with a non-redundant database derived from the 600,000+ viral sequences in GenBank organized into 4080 taxa. An individual read successfully aligned to the viral database was considered to be a “hit”. Normalized MS specimen hit rates for each viral taxon were compared to the distribution of hits in the normal controls. Seventeen MS and 11 control brain extracts were sequenced, yielding 4–10 million sequences (“reads”) each. Over-representation of sequence from at least one of 12 viral taxa was observed in 7 of the 17 MS samples. Sequences resembling other viruses previously implicated in the pathogenesis of MS were not significantly enriched in any of the diseased brain specimens. Sequences from GB virus C (GBV-C), a flavivirus not previously isolated from brain, were enriched in one of the MS samples. GBV-C in this brain specimen was confirmed by specific amplification in this single MS brain specimen, but not in the 30 other MS brain samples available. The entire 9.4 kb sequence of this GBV-C isolate is reported here. This study shows the feasibility of deep sequencing for the detection of occult viral infections in the brains of deceased persons with MS. The first isolation of GBV-C from human brain is reported here.</p> </div
Virus-like sequence short read assembly.
1<p>students t-test (minimum value) corrected for multiple comparisons by the Bonferroni method.</p>2<p>maximum length of all the assembled reads that aligned to the indicated virus.</p>3<p>number of MS brain specimens that had reads with significant homology (MegaBlast Expect ≤0.1) to the indicated viral sequences.</p>4<p>The assembly of short reads did not improve alignment with the specified viral sequences.</p>5<p>Assembly revealed homology to human mitochondrial and host integration sites.</p
Representational Analysis.
<p>Virus-like sequences overrepresented in MS brain specimens compared with controls are displayed. Bonferroni corrected p-values beginning with 0.05 are displayed. Each row (labeled, N = 64) represents an overrepresented viral taxon. Each column (N = 17) represents a different MS brain specimen. The shaded yellow boxes represent significant hits. The GBV-C sequences confirmed by PCR in one of the specimens is circled in red.</p
Virus-like sequence short read assembly.
1<p>students t-test (minimum value) corrected for multiple comparisons by the Bonferroni method.</p>2<p>maximum length of all the assembled reads that aligned to the indicated virus.</p>3<p>number of MS brain specimens that had reads with significant homology (MegaBlast Expect ≤0.1) to the indicated viral sequences.</p>4<p>The assembly of short reads did not improve alignment with the specified viral sequences.</p>5<p>Assembly revealed homology to human mitochondrial and host integration sites.</p