12 research outputs found

    SARS-CoV-2 lineage dynamics in England from September to November 2021: high diversity of Delta sub-lineages and increased transmissibility of AY.4.2

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    Background: Since the emergence of SARS-CoV-2, evolutionary pressure has driven large increases in the transmissibility of the virus. However, with increasing levels of immunity through vaccination and natural infection the evolutionary pressure will switch towards immune escape. Genomic surveillance in regions of high immunity is crucial in detecting emerging variants that can more successfully navigate the immune landscape. Methods: We present phylogenetic relationships and lineage dynamics within England (a country with high levels of immunity), as inferred from a random community sample of individuals who provided a self-administered throat and nose swab for rt-PCR testing as part of the REal-time Assessment of Community Transmission-1 (REACT-1) study. During round 14 (9 September–27 September 2021) and 15 (19 October–5 November 2021) lineages were determined for 1322 positive individuals, with 27.1% of those which reported their symptom status reporting no symptoms in the previous month. Results: We identified 44 unique lineages, all of which were Delta or Delta sub-lineages, and found a reduction in their mutation rate over the study period. The proportion of the Delta sub-lineage AY.4.2 was increasing, with a reproduction number 15% (95% CI 8–23%) greater than the most prevalent lineage, AY.4. Further, AY.4.2 was less associated with the most predictive COVID-19 symptoms (p = 0.029) and had a reduced mutation rate (p = 0.050). Both AY.4.2 and AY.4 were found to be geographically clustered in September but this was no longer the case by late October/early November, with only the lineage AY.6 exhibiting clustering towards the South of England. Conclusions: As SARS-CoV-2 moves towards endemicity and new variants emerge, genomic data obtained from random community samples can augment routine surveillance data without the potential biases introduced due to higher sampling rates of symptomatic individuals. © 2022, The Author(s)

    Primary ankylosing spondylitis: Patterns of disease in a Brazilian population of 147 patients

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    Objective. To analyze patterns of disease in a population of Brazilian patients with primary ankylosing spondylitis (AS). Methods. Retrospective study (1988-98) analyzing 147 patients with a diagnosis of primary AS according to the modified New York criteria. Selected patients had complete clinical (initial symptom, axial and peripheral involvement, heel enthesitis, extraarticular manifestations) and radiological (sacroiliac, lumbar, thoracic, and cervical spine) investigations, and these data were compared with sex, race, age at onset, and HLA-B27. Results. There was a predominance of men (84.4%), Caucasian race (75.5%), adult onset (> 16 years, 85%), and positive HLA-B27 (78.2%). Family history of AS was noted in 14.3% of the patients. Pure axial AS was observed in 37 patients (25.2%). The predominant initial symptoms were inflammatory low back pain (61.9%) and peripheral arthritis (22.4%). Thoracic and cervical spine involvement was noted in 70.1% of the patients; radiological findings included syndesmophytes in 46.9% and "bamboo spine" in 20.4% of patients. The extraaxial joints most frequently involved were: ankles (39.5%), hips (36.1%), knees (29.3%), shoulders (19%), and sternoclaviculars (14.3%); heel enthesitis was present in 22.4%. Acute anterior uveitis was noted in 14.3% of patients. Male sex was associated with involvement of thoracic spine (p = 0.002), cervical spine (p = 0.002), and hips (p = 0.042), whereas female sex was associated with sternoclavicular (p = 0.024) involvement. Caucasian race presented higher frequency of positive family history (p = 0.023); there was no statistical significance of clinical and radiological variables compared with African-Brazilians. Juvenile onset AS presented higher frequency of ankle (p = 0.012) and knee (p = 0.001) involvement, heel enthesitis (p = 0.001), and total hip replacement (p = 0.038), whereas adult onset was associated with thoracic (p = 0.026) and cervical spine (p = 0.026) involvement and positive family history (p = 0.044), Positive HLA-B27 was associated with ankle involvement (p = 0.007) and heel enthesitis (p = 0.013). Conclusion. In this population women showed a milder axial involvement, Caucasian race presented axial and peripheral involvement similar to African-Brazilians, juvenile onset AS was associated with articular involvement of the lower limbs, and positive HLA-B27 was associated with ankle involvement.28356056

    Association between psoriasis vulgaris and MHC-DRB, -DQB genes as a contribution to disease diagnosis

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    We analyzed 100 control individuals and 60 patients with psoriasis vulgaris from the population of Campinas, Brazil. Typification of class 11 HLA alleles (HLA-DRB1-5 and -DQB1) was carried out through the DNA/PCR/SSP at medium and high resolution. DNA was extracted through a salting-out procedure: 13 DRB1 alleles, 3 DRB3 alleles, I DRB4 allele, 2 DRB5 alleles, and 5 DQB1 alleles were identified at a medium resolution using the PCR/SSP, and 45 DRB1 alleles were identified at a high resolution in analyzed patients. Results showed associations with psoriasis vulgaris: positive associations HLA-DRB3*02 (p < 0.05, chi(2) = 5.10, RR = 2.14); HLA-DRB1*0102 alleles (p < 0.05, RR = 5.44). Negative associations were found for HLA-DRB4*01 (chi(2) = 3.23, RR = 0.55) and HLA-DRB1*1302 alleles (p < 0.05, RR = 0.23). The haplotypes revealed positive association for HLA-DRB1*0102/DQB1*05 (p < 0.05, RR = 5.44) and HLA-DRB1*0701/DQB1*03 alleles (p < 0.02, RR = 9.00). These findings suggest a possible association of the DRB1 allele with the group of patients showing an early onset of the illness, as well as an association with haplotypes HLA-DRB1*0102/DQB1*05 and HLA-DRB1*0701-DQB1*03.15315916

    Relationship between HLA antigens and infectious agents in contributing towards the development of Graves' disease

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    Graves' disease (GD) is an autoimmune thyroid disorder which is associated with the human leucocyte antigens HLA-DR3 and DQA1* O501 in Caucasians. We have explored the possibility that some patients with certain HLA specificities develop anti-HLA antibodies which are correlated with environmental factors that may contribute to the development of GD. We studied 40 GD patients and 157 healthy individuals (controls). Serology was used to type HLA-A -B, -Cw, and -DR antigens. The frequencies of these antigens in relation to lymphocytotoxic anti-HLA-A-B-Cw-DR antibodies and two environmental factors (Yersinia enterocolitica and Coxsackie B virus) were determined. The frequencies of HLA-B15, -B21 and DR3 antigens were increased, whereas HLA-DRS antigen was decreased in GD patients. A significant association between HLA-DR3 antigen and lymphocytotoxic antibodies was observed, i. e., IgGs from GD patients were cytotoxic to HLA-DR3+ normal B cells. Following absorption with Yersinia enterocolitica or Coxsackie-B-virus, only Coxsackie-B virus completely inhibited the lymphocytotoxic reactions against HLA-DR3(+) B cells. Besides confirming the association of HLA-DR3 with GD, this study also suggests the role of Coxsackie-reative HLA-DR3 antibodies as contributing factors to the pathogenesis of the disease.2741671172

    Molecular identification of the HLA-DRB1-DQB1 for diagnosis and follow-up of acute leukemias

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    Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)We analyzed a group of 45 Brazilian individuals, 30 with acute myeloid leukemia (AML), 15 with acute lymphoid leukemia (ALL) and 100 healthy controls to assess genetic factor risk and HLA association contribution to the disease. Patient rates were compared with age and sex-matched control groups by directly typing the HLA-DRB1/3/4/5 and -DQB1 loci by PCR analysis. We observed significantly increased allelic distribution of HIA-DRB1*07 in AML patients and of HLA-DRB1*03 in ALL patients, which suggests that individuals in both groups are susceptible to the disease. We also found significantly decreased allelic distribution of HIA-DQB1*04 in AML patients and of HLA-DRB1*04 and -DQB1*03 in ALL patients, which suggests protection against the disease. We further found increased HLA-DRB1*07 and -DQB1*02 haplotypes in AML patients, which suggests susceptibility to the disease and decreased HLA-DRB1*04 and -DQB1*03 haplotypes in ALL patients, which also suggests protection against the disease. Future studies with larger and/or multicentric samples will be required for better comprehension of the HLA role in acute leukemia pathogenesis. (C) 2009 Elsevier Inc. All rights reserved.4426973Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)(Fundo de Apoio ao Ensino e a Pesquisa-FAEP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Undifferentiated spondyloarthropathies: A 2-year follow-up study

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    The aim of the study was to analyse the 2-year follow-up of a series of patients with the diagnosis of undifferentiated spondyloarthropathy (uSpA). A prospective study was carried out analysing 68 patients with symptomatic uSpA who fulfilled the European Spondylarthropathy Study Group (ESSG) criteria for seronegative spondyloarthropathies (SpA) and were aged between 18 and 50 years. Inclusion criteria included inflammatory low back pain (ILBP) (without radiographic sacroiliitis), asymmetric oligoarthritis (predominantly affecting large joints in the lower limbs) and heel enthesopathies (Achilles tendinitis and/or plantar fasciitis). Imaging methods included pelvic radiography (at study entry and after 2 years) and calcaneal radiography (at study entry). There was a predominance of male gender (78%), caucasoid race (72%) and positive HLA-B27 (54%), with a mean age of 31 years and mean disease duration of 5 years. The first disease manifestations were ILBP (49%), asymmetric oligoarthritis (35%) and heel enthesopathies (16%), A positive family history of a definite SpA was mentioned by 9% of the patients. Seventeen patients (25%) scored 5 points in the Amor set of SpA criteria; logistic regression analysis showed that HLA-B27, heel enthesopathy and asymmetric oligoarthritis were significantly associated with Amor criteria greater than or equal to6, whereas ILBP was associated with Amor criteria <6. Male sex was associated with heel enthesopathies (p = 0.041) and ankle involvement (p = 0.015). Caucasoid race was associated with ILBP (p = 0.015) and buttock pain (p = 0.047). Positive HLA-B27 was associated with wrist involvement (p = 0.019) and Amor criteria greater than or equal to6 (p = 0.001). After a 2-year follow-up the following outcomes were observed: uSpA 75%; disease remission 13%; ankylosing spondylitis 10%; psoriatic arthritis 2%. Logistic regression analysis showed that buttock pain and positive HLA-B27 (trend) were statistically associated with progression to a definite SpA. In conclusion, uSpA can represent a provisional diagnosis in the group of SpA and a systematic follow-up is necessary in order to better establish the different patterns of the disease.20320120

    Molecular mechanisms associated with donor-specific microchimerism in peripheral blood of Brazilian patients after liver transplantation

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    A large number of studies in liver transplantation have demonstrated allogeneic microchimerism. The clinical and immunologic implications of this finding remain inconclusive, just as the influence of HLA mismatch and donor alloreactivity also are controversial. The present study analyzed the presence of allogeneic microchimerism in liver transplant recipients in relation to donor leukocyte kinetics and rejection episodes. The study was extended to determining the influence of immunogenetic factors in patients after liver transplantation. The presence of allogeneic microchimerism was analyzed on peripheral blood of 50 recipients. DNA extracted from the samples was subjected to typing for HLA-DRB1 and -DQB1 alleles by polymerase chain reactions using sequence-specific primers (PCR/SSP). Microchimerism was identified by nested PCR/SSP. Microchimerism was detected in 72% of patients. There was significant effect of microchimerism on rejection episodes (P =.002), while HLA mismatches did not show significance for one or two mismatches (P =.98). Allogeneic microchimerism detected in the majority of liver transplant patients was observed to be significantly associated with rejection episodes.3851411141

    Association of HLA-A, -B, -C genes and TNF microsatellite polymorphism with psoriasis vulgaris: a study of genetic risk in Brazilian patients

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    This study investigated the genetic association of HLA class I genes and TNF-alpha microsatellites. HLA-A, -B, -C typing was carried out in 92 psoriasis vulgaris patients and 160 healthy individuals using a PCR-SSP method. 70 patients and 71 controls were typed for five microsatellite polymorphisms, TNFa-e. HLA-B*13 Cw*06, HLA-B*57 Cw*06 and HLA-B*39 Cw*12 haplotypes were found to be increased in patients with psoriasis type I when compared to controls, which could determine the susceptibility to development of psoriasis. TNFa4, TNFb1, TNFe1 and TNFa2 b1 c2 d4 el haplotypes showed a decreased frequency (p < 0.05) in psoriasis patients when compared to controls. HLA-B*13 allele and HLA-B * 13 Cw*06, TNFa11 b4 c1 d3 e3 haplotypes showed increased frequencies (p < 0.05) in patients with type II psoriasis, which suggests susceptibility to the onset of psoriasis. Our results detected polymorphisms of the HLA class I and microsatellite TNF locus which could be markers of genetic predisposition to the disease.16552352

    Undifferentiated spondyloarthropathies in Brazilians: Importance of HLA-B27 and the B7-CREG alleles in characterization and disease progression

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    Objective. To analyze the profile of the HLA-B27 and B7 cross-reactive group (CREG) alleles and the role of these markers in disease characterization and progression in patients with undifferentiated spondyloarthropathies (uSpA). Methods. A total of 80 patients with a diagnosis of uSpA (40 HLA-B27 positive and 40 HLA-B27 negative) were prospectively studied for 2 years. The control group consisted of 66 HLA-B27 positive and 112 HLA-B27 negative individuals without a history of seronegative SpA. HLA-B alleles were typed at low (B7-CREG alleles, i.e., B*7, B*54, B*55, B*56, B*40, B*42) or high resolution (B*27 alleles) using polymerase chain reaction-amplified DNA hybridized with sequence-specific oligonucleotide probes. Results. HLA-B*2705 was the most frequent allele, observed in 92.5% of the patients and in 77% of the controls, followed by the HLA-B*2702, observed in 5% of the patients and in 12% of the controls. HLA-B*2704 was observed in only one patient (2.5%), and was absent in the control population. HLA-B*2703 (6%) and HLA-B*2707 (5%) alleles were observed only in controls. No associations between HLA-B*27 alleles or B7-CREG alleles and any specific manifestation of uSpA were observed. HLA-B27 positive patients more frequently presented juvenile onset SpA (p=0.002) and progression to ankylosing spondylitis (AS) (p=0.03) than did HLA-B27 negative patients. The B7-CREG alleles were observed in 5% of the HLA-B27 positive uSpA group, in 25% of the HLA-B27 negative uSpA group, in 7% of the HLA-B27 positive controls, and in 13% of the HLA-B27 negative controls; a significant association was observed between the presence of the B7-CREG and the HLA-B27 negative uSpA group (p=0.012). Conclusion. The frequency of the HLA-B*2705 allele among the B27 positive uSpA patients of this series was closely similar to that reported for patients with ankylosing spondylitis (AS). The presence of HLA-B*27 alleles was associated with the progression to AS, and the presence of B7-CREG was associated with uSpA in the HLA-B27 negative group.30122632263
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