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BACKGROUND: Celiac disease (CeD) has an estimated prevalence of 1%-3%. The classical clinical presentation is malabsorption, but now patients may present with more subtle symptoms such as constipation, osteoporosis, or iron deficiency anemia. Children may also present with poor growth.CeD has a strong genetic component, and high-risk groups include first-degree relatives with CeD, patients with co-existing autoimmune diseases, and patients with chromosomal aberrations. CONTENT: Diagnostic tests for CeD include duodenal histology, serology, and genetic testing. Duodenal histology has traditionally been the gold standard of diagnosis. However, serological tests, especially IgA tissue transglutaminase antibodies (TTG-IgA), are widely used and diagnostic algorithms are based primarily on TTG-IgA as a starting point. Human leukocyte antigen typing may also be incorporated to determine genetic risk for CeD. Guidelines for children endorse biopsy avoidance provided high levels of TTG-IgA, with diagnostic accuracy being comparable to duodenal biopsy. Confirmation may be achieved by identifying IgA endomysial antibodies in a separate blood sample. Subjects with low positive TTG-IgA levels and subjects with IgA deficiency need a biopsy to establish a diagnosis of CeD. The clinical follow-up of CeD usually includes a repeat TTG-IgA examination. In adults, healing may be delayed or incomplete, and a rare consequence of refractory celiac disease is transformation to enteric T-cell lymphoma. SUMMARY: Laboratory testing, in particular TTG-IgA, plays a central role in the diagnosis and has an accuracy comparable to histology. Diagnostic algorithms utilizing laboratory testing are critical for the development of novel strategies to improve diagnosis.
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BACKGROUND: Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein not previously described in the human central nervous system (CNS). OBJECTIVES: We determined MFAP4 CNS expression and measured cerebrospinal fluid (CSF) and serum levels. METHODS: Tissue was sampled at autopsy from patients with acute multiple sclerosis (MS) (n = 3), progressive MS (n = 3), neuromyelitis optica spectrum disorder (NMOSD) (n = 2), and controls (n = 9), including 6 healthy controls (HC). MFAP4 levels were measured in 152 patients: 49 MS, 62 NMOSD, 22 myelin oligodendrocyte glycoprotein-associated disease (MOGAD), and 19 isolated optic neuritis (ION). RESULTS: MFAP4 localized to meninges and vascular/perivascular spaces, intense in the optic nerve. At sites of active inflammation, MFAP4 reactivity was reduced in NMOSD and acute MS and less in progressive MS. CSF MFAP4 levels were reduced during relapse and at the onset of diseases (mean U/mL: MS 14.3, MOGAD 9.7, and ION 14.6 relative to HC 17.9. (p = 0.013, p = 0.000, and p = 0.019, respectively). Patients with acute ON (n = 68) had reduced CSF MFAP4 (mean U/mL: 14.5, p = 0.006). CSF MFAP4 levels correlated negatively with relapse severity (rho = -0.41, p = 0.017). CONCLUSION: MFAP4 immunoreactivity was reduced at sites of active inflammation. CSF levels of MFAP4 were reduced following relapse and may reflect disease activity.
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Esclerose Múltipla Crônica Progressiva , Esclerose Múltipla , Neuromielite Óptica , Humanos , Glicoproteína Mielina-Oligodendrócito , Neuromielite Óptica/líquido cefalorraquidiano , Sistema Nervoso Central , Inflamação , Autoanticorpos , Aquaporina 4/líquido cefalorraquidiano , Proteínas de Transporte , Glicoproteínas , Proteínas da Matriz ExtracelularRESUMO
Contamination of white-brined cheeses (WBCs) with yeasts is of major concern in the dairy industry. This study aimed to identify yeast contaminants and characterize their succession in white-brined cheese during a shelf-life of 52 weeks. White-brined cheeses added herbs (WBC1) or sundried tomatoes (WBC2) were produced at a Danish dairy and incubated at 5 °C and 10 °C. An increase in yeast counts was observed for both products within the first 12-14 weeks of incubation and stabilized afterwards varying in a range of 4.19-7.08 log CFU/g. Interestingly, higher incubation temperature, especially in WBC2, led to lower yeast counts, concurrently with higher diversity of yeast species. Observed decrease in yeast counts was, most likely, due to negative interactions between yeast species leading to growth inhibition. In total, 469 yeast isolates from WBC1 and WBC2 were genotypically classified using the (GTG)5-rep-PCR technique. Out of them, 132 representative isolates were further identified by sequencing the D1/D2 domain of the 26 S rRNA gene. Predominant yeast species in WBCs were Candida zeylanoides and Debaryomyces hansenii, while Candida parapsilosis, Kazachstania bulderi, Kluyveromyces lactis, Pichia fermentans, Pichia kudriavzevii, Rhodotorula mucilaginosa, Torulaspora delbrueckii, and Wickerhamomyces anomalus were found in lower frequency. Heterogeneity of yeast species in WBC2 was generally larger compared to WBC1. This study indicated that, along with contamination levels, taxonomic heterogeneity of yeasts is an important factor influencing yeast cell counts, as well as product quality during storage.
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Queijo , Leveduras/genética , Reação em Cadeia da PolimeraseRESUMO
BACKGROUND: Studies presenting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection fatality rate (IFR) for healthy individuals are warranted. We estimate IFR by age and comorbidity status using data from a large serosurvey among Danish blood donors and nationwide data on coronavirus disease 2019 (COVID-19) mortality. METHODS: Danish blood donors aged 17-69 years donating blood October 2020-February 2021 were tested with a commercial SARS-CoV-2 total antibody assay. IFR was estimated for weeks 11 to 42, 2020 and week 43, 2020 to week 6, 2021, representing the first 2 waves of COVID-19 epidemic in Denmark. RESULTS: In total, 84944 blood donors were tested for antibodies. The seroprevalence was 2% in October 2020 and 7% in February 2021. Among 3898039 Danish residents aged 17-69 years, 249 deaths were recorded. The IFR was low for people <51 years without comorbidity during the 2 waves (combined IFR=3.36 per 100000 infections). The IFR was below 3 for people aged 61-69 years without comorbidity. IFR increased with age and comorbidity but declined from the first to second wave. CONCLUSIONS: In this nationwide study, the IFR was very low among people <51 years without comorbidity.
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Anticorpos Antivirais/sangue , Doadores de Sangue , COVID-19/diagnóstico , SARS-CoV-2/isolamento & purificação , Adolescente , Adulto , Idoso , COVID-19/sangue , COVID-19/epidemiologia , Comorbidade , Dinamarca/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto JovemRESUMO
PURPOSE: Selective IgA deficiency (IgAD) is the most common primary immunodeficiency, frequently leading to only minor clinical complaints. IgAD may be associated with autoimmune diseases such as celiac disease (CeD). Although IgAD is thought to precede CeD and autoimmunity, the association between the two conditions has not been clarified. METHODS: Routine techniques were used to measure serum IgA and celiac diagnostic markers as transglutaminase 2 IgA (TG2-IgA) and deamidated gliadin IgG and for immunohistochemistry for IgG, IgM, and IgA. RESULTS: We report two childhood cases of complete IgA deficiency that evolved after the diagnosis of CeD and the start of a gluten-free diet. Histology showed persistence of IgA in the intestinal mucosa. CONCLUSION: Both children with CeD showed IgA deficiency that unexpectedly developed after the initiation of a gluten-free diet. This supports IgA deficiency as a process that develops gradually and occurs due to specific defects in immunoregulation.
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Doença Celíaca , Deficiência de IgA , Autoanticorpos , Doença Celíaca/complicações , Doença Celíaca/diagnóstico , Criança , Gliadina , Humanos , Deficiência de IgA/complicações , Deficiência de IgA/diagnóstico , Imunoglobulina A , Imunoglobulina G , Imunoglobulina M , TransglutaminasesRESUMO
Soluble inflammatory mediators (SIM) can be predictive of treatment outcome in antiviral treatment of chronic hepatitis C. Recently, it was shown that a subgroup of patients can be cured with four weeks of therapy. We here profiled patients for 70 SIM before and during treatment of hepatitis C with glecaprevir/pibrentasvir (GLE/PIB) +/- ribavirin. Proximity extension assay was performed in a total of 32 patients. Pre-treatment SIM profiles did not distinguish patients achieving an SVR (n = 21) from patients experiencing antiviral relapse (n = 11). However, after 4 weeks of therapy, eight markers were identified that could distinguish patients with SVR from the relapsed group, namely MMP-10, CCL20, CXCL11, FGF-23, TNF, MCP-2, IL-18R1 and CXCL10. Thus, this study shows that a distinct on-treatment immune profile is associated with cure of HCV infection after ultrashort treatment.
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Hepatite C Crônica , Hepatite C , Antivirais , Genótipo , Hepacivirus , Hepatite C/tratamento farmacológico , Hepatite C Crônica/tratamento farmacológico , Humanos , Mediadores da Inflamação , Prolina/uso terapêutico , Quinoxalinas/efeitos adversosRESUMO
The persistence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies is a matter of importance regarding the coronavirus disease 19 (COVID-19) pandemic. To observe antibody dynamics, 105 blood donors, positive for SARS-CoV-2 antibodies by a lateral flow test within a seroprevalence study, were included in this study. Thirty-nine (37%) of 105 the donors were confirmed positive by a total Ig Wantai enzyme-linked immunosorbent assay (ELISA). Three (8%) in this group of 39 reported severe and 26/39 (67%) mild to moderate COVID-19 symptoms. By further ELISA-testing, 33/39 (85%) donors were initially positive for IgG antibodies, 31/39 (79%) for IgA, and 32/39 (82%) for IgM, while 27/39 (69%) were positive for all three isotypes. Persistence of IgG, IgA, and IgM was observed in 73%, 79%, and 32% of donors, respectively, after 6-9 months of observation. For IgM antibodies, the decline in the proportion of positive donors was statistically significant (p = 0.002) during 12 months observation, for IgG only the decline at 3 months was statistically significant (p = 0.042). Four donors exhibited notable increases in antibody levels. In conclusion, persistent SARS-CoV-2 IgA antibodies and IgG antibodies at 6-9 months are present in approximately three of four individuals with previous mild to moderate COVID-19.
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Anticorpos Antivirais/sangue , Doadores de Sangue/estatística & dados numéricos , COVID-19/imunologia , SARS-CoV-2/imunologia , Adulto , COVID-19/sangue , COVID-19/epidemiologia , Dinamarca/epidemiologia , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Cinética , Masculino , Reinfecção/sangue , Reinfecção/epidemiologia , Reinfecção/imunologia , Estudos Soroepidemiológicos , Índice de Gravidade de Doença , Adulto JovemRESUMO
OBJECTIVES: The objective of this study was to establish an unselected cohort of Danish adolescents and estimate the prevalence of undiagnosed celiac disease (CeD). METHODS: The Glutenfunen cohort participants were recruited from an unselected subsample of the Danish National Birth Cohort, defined as participants living in the Island of Funen, Denmark. We invited all 7431 eligible participants in the age range of 15 to 21âyears to a clinical visit. CeD diagnosis was based on screening with IgA transglutaminase antibodies (TG2-IgA) and if positive, was followed by duodenal biopsies compatible with CeD (Marsh 2-3). We calculated the prevalence of CeD in the Glutenfunen cohort as the number of CeD cases diagnosed before and during the study divided by the number of participants in the Glutenfunen cohort. RESULTS: We included 1266 participants in the Glutenfunen cohort (17%, 1266/7431). 1.1% (14 of 1266 participants) had CeD diagnosed before entering the cohort and based on the Danish National Patient Register, 0.2% of the nonparticipants (14 of 6165) had a diagnosis of CeD. In total, 2.6% (33 participants) had TG2 IgA above the upper limit of normal. Nineteen participants had duodenal biopsies compatible with CeD. The prevalence of CeD in the Glutenfunen cohort was 2.6% [(14â+â19)/1266]. CONCLUSIONS: Our study suggests that CeD is much more common than expected among Danish adolescents, comparable to other European countries, and that the majority were asymptomatic or oligosymptomatic and were only found because of the screening procedure.
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Doença Celíaca , Adolescente , Autoanticorpos , Doença Celíaca/diagnóstico , Doença Celíaca/epidemiologia , Dinamarca/epidemiologia , Humanos , Imunoglobulina A , Prevalência , Transglutaminases , Adulto JovemRESUMO
BACKGROUND: The pandemic due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has tremendous consequences for our societies. Knowledge of the seroprevalence of SARS-CoV-2 is needed to accurately monitor the spread of the epidemic and to calculate the infection fatality rate (IFR). These measures may help the authorities make informed decisions and adjust the current societal interventions. The objective was to perform nationwide real-time seroprevalence surveying among blood donors as a tool to estimate previous SARS-CoV-2 infections and the population-based IFR. METHODS: Danish blood donors aged 17-69 years giving blood 6 April to 3 May were tested for SARS-CoV-2 immunoglobulin M and G antibodies using a commercial lateral flow test. Antibody status was compared between geographical areas, and an estimate of the IFR was calculated. Seroprevalence was adjusted for assay sensitivity and specificity taking the uncertainties of the test validation into account when reporting the 95% confidence intervals (CIs). RESULTS: The first 20â 640 blood donors were tested, and a combined adjusted seroprevalence of 1.9% (95% CI, .8-2.3) was calculated. The seroprevalence differed across areas. Using available data on fatalities and population numbers, a combined IFR in patients <70 years is estimated at 89 per 100â 000 (95% CI, 72-211) infections. CONCLUSIONS: The IFR was estimated to be slightly lower than previously reported from other countries not using seroprevalence data. The IFR is likely severalfold lower than the current estimate. We have initiated real-time nationwide anti-SARS-CoV-2 seroprevalence surveying of blood donations as a tool in monitoring the epidemic.
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Doadores de Sangue , COVID-19 , Adolescente , Adulto , Idoso , Anticorpos Antivirais , Humanos , Pessoa de Meia-Idade , SARS-CoV-2 , Estudos Soroepidemiológicos , Adulto JovemRESUMO
In this study we show increased biomass formation for four species of food-grade propionic acid bacteria (Acidipropionibacterium acidipropionici, Acidipropionibacterium jensenii, Acidipropionibacterium thoenii and Propionibacterium freudenreichii) when exposed to oxygen, implicating functional respiratory systems. Using an optimal microaerobic condition, P. freudenreichii DSM 20271 consumed lactate to produce propionate and acetate initially. When lactate was depleted propionate was oxidized to acetate. We propose to name the switch from propionate production to consumption in microaerobic conditions the 'propionate switch'. When propionate was depleted the 'acetate switch' occurred, resulting in complete consumption of acetate. Both growth rate on lactate (0.100 versus 0.078 h-1 ) and biomass yield (20.5 versus 8.6 g* mol-1 lactate) increased compared to anaerobic conditions. Proteome analysis revealed that the abundance of proteins involved in the aerobic and anaerobic electron transport chains and major metabolic pathways did not significantly differ between anaerobic and microaerobic conditions. This implicates that P. freudenreichii is prepared for utilizing O2 when it comes available in anaerobic conditions. The ecological niche of propionic acid bacteria can conceivably be extended to environments with oxygen gradients from oxic to anoxic, so-called microoxic environments, as found in the rumen, gut and soils, where they can thrive by utilizing low concentrations of oxygen.
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Propionibacterium freudenreichii , Dióxido de Carbono , Ácido Láctico , Propionatos , PropionibacteriaceaeRESUMO
OBJECTIVES: Systemic lupus erythematosus (SLE) is an autoimmune disease with extensive heterogeneity in disease presentation between patients, which is likely due to an underlying molecular diversity. Here, we aimed at elucidating the genetic aetiology of SLE from the immunity pathway level to the single variant level, and stratify patients with SLE into distinguishable molecular subgroups, which could inform treatment choices in SLE. METHODS: We undertook a pathway-centred approach, using sequencing of immunological pathway genes. Altogether 1832 candidate genes were analysed in 958 Swedish patients with SLE and 1026 healthy individuals. Aggregate and single variant association testing was performed, and we generated pathway polygenic risk scores (PRS). RESULTS: We identified two main independent pathways involved in SLE susceptibility: T lymphocyte differentiation and innate immunity, characterised by HLA and interferon, respectively. Pathway PRS defined pathways in individual patients, who on average were positive for seven pathways. We found that SLE organ damage was more pronounced in patients positive for the T or B cell receptor signalling pathways. Further, pathway PRS-based clustering allowed stratification of patients into four groups with different risk score profiles. Studying sets of genes with priors for involvement in SLE, we observed an aggregate common variant contribution to SLE at genes previously reported for monogenic SLE as well as at interferonopathy genes. CONCLUSIONS: Our results show that pathway risk scores have the potential to stratify patients with SLE beyond clinical manifestations into molecular subsets, which may have implications for clinical follow-up and therapy selection.
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Apresentação de Antígeno/genética , Imunidade Inata/genética , Interferon Tipo I/imunologia , Lúpus Eritematoso Sistêmico/genética , Linfopoese/genética , Linfócitos T/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Coagulação Sanguínea/genética , Estudos de Casos e Controles , Análise por Conglomerados , Ativação do Complemento/genética , Feminino , Humanos , Janus Quinases/genética , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Herança Multifatorial , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição STAT/genética , Análise de Sequência de DNA , Transdução de Sinais/genética , Suécia , População Branca , Adulto JovemRESUMO
Calcium (Ca) is a key micronutrient of high relevance for human nutrition that also influences the texture and taste of dairy products and their processability. In bovine milk, Ca is presented in several speciation forms, such as complexed with other milk components or free as ionic calcium while being distributed between colloidal and serum phases of milk. Partitioning of Ca between these phases is highly dynamic and influenced by factors, such as temperature, ionic strength, pH, and milk composition. Processing steps used during the manufacture of dairy products, such as preconditioning, concentration, acidification, salting, cooling, and heating, all contribute to modify Ca speciation and partition, thereby influencing product functionality, product yield, and fouling of equipment. This review aims to provide a comprehensive understanding of the influence of Ca partition on dairy products properties to support the development of kinetics models to reduce product losses and develop added-value products with improved functionality. To achieve this objective, approaches to separate milk phases, analytical approaches to determine Ca partition and speciation, the role of Ca on protein-protein interactions, and their influence on processing of dairy products are discussed.
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Proteínas do Leite , Oligoelementos , Animais , Cálcio da Dieta , Humanos , Micronutrientes , LeiteRESUMO
ß-galactosidases, commonly referred to as lactases, are used for producing lactose-free dairy products. Lactases are usually purified from microbial sources, which is a costly process. Here, we explored the potential that lies in using whole cells of a food-grade dairy lactic acid bacterium, Streptococcus thermophilus, as a substitute for purified lactase. We found that S. thermophilus cells, when treated with the antimicrobial peptide nisin, were able to hydrolyze lactose efficiently. The rate of hydrolysis increased with temperature; however, above 50 °C, stability was compromised. Different S. thermophilus strains were tested, and the best candidate was able to hydrolyze 80% of the lactose in a 50 g/L solution in 4 h at 50 °C, using only 0.1 g/L cells (dry weight basis). We demonstrated that it was possible to grow the cell catalyst on dairy waste, and furthermore, that a cell-free supernatant of a culture of a nisin-producing Lactococcus lactis strain could be used instead of purified nisin, which reduced cost of use significantly. Finally, we tested the cell catalysts in milk, where lactose also was efficiently hydrolyzed. The method presented is natural and low-cost, and allows for production of clean-label and lactose-free dairy products without using commercial enzymes from recombinant microorganisms. KEY POINTS: ⢠Nisin-permeabilized Streptococcus thermophilus cells can hydrolyze lactose efficiently. ⢠A low-cost and more sustainable alternative to purified lactase enzymes. ⢠Reduction of overall sugar content. ⢠Clean-label production of lactose-free dairy products.
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Lactase/metabolismo , Lactobacillales/metabolismo , Animais , Permeabilidade da Membrana Celular/efeitos dos fármacos , Meios de Cultura , Hidrólise , Lactobacillales/crescimento & desenvolvimento , Lactococcus lactis/crescimento & desenvolvimento , Lactococcus lactis/metabolismo , Lactose/análise , Lactose/metabolismo , Leite/química , Leite/microbiologia , Nisina/metabolismo , Nisina/farmacologia , Streptococcus thermophilus/efeitos dos fármacos , Streptococcus thermophilus/crescimento & desenvolvimento , Streptococcus thermophilus/metabolismo , TemperaturaRESUMO
BACKGROUND & AIMS: The guidelines of the European Society of Pediatric Gastroenterology, Hepatology, and Nutrition allow for diagnosis of celiac disease without biopsies in children with symptoms and levels of immunoglobulin A against tissue-transglutaminase (TGA-IgA) 10-fold or more the upper limit of normal (ULN), confirmed by detection of endomysium antibodies (EMA) and positivity for HLA-DQ2/DQ8. We performed a large, international prospective study to validate this approach. METHODS: We collected data from consecutive pediatric patients (18 years or younger) on a gluten-containing diet who tested positive for TGA-IgA from November 2011 through May 2014, seen at 33 pediatric gastroenterology units in 21 countries. Local centers recorded symptoms; measurements of total IgA, TGA, and EMA; and histopathology findings from duodenal biopsies. Children were considered to have malabsorption if they had chronic diarrhea, weight loss (or insufficient gain), growth failure, or anemia. We directly compared central findings from 16 antibody tests (8 for TGA-IgA, 1 for TGA-IgG, 6 for IgG against deamidated gliadin peptides, and 1 for EMA, from 5 different manufacturers), 2 HLA-DQ2/DQ8 tests from 2 manufacturers, and histopathology findings from the reference pathologist. Final diagnoses were based on local and central results. If all local and central results were concordant for celiac disease, cases were classified as proven celiac disease. Patients with only a low level of TGA-IgA (threefold or less the ULN) but no other results indicating celiac disease were classified as no celiac disease. Central histo-morphometry analyses were performed on all other biopsies and cases were carefully reviewed in a blinded manner. Inconclusive cases were regarded as not having celiac disease for calculation of diagnostic accuracy. The primary aim was to determine whether the nonbiopsy approach identifies children with celiac disease with a positive predictive value (PPV) above 99% in clinical practice. Secondary aims included comparing performance of different serological tests and to determine whether the suggested criteria can be simplified. RESULTS: Of 803 children recruited for the study, 96 were excluded due to incomplete data, low level of IgA, or poor-quality biopsies. In the remaining 707 children (65.1% girls; median age, 6.2 years), 645 were diagnosed with celiac disease, 46 were found not to have celiac disease, and 16 had inconclusive results. Findings from local laboratories of TGA-IgA 10-fold or more the ULN, a positive result from the test for EMA, and any symptom identified children with celiac disease (n = 399) with a PPV of 99.75 (95% confidence interval [CI], 98.61-99.99); the PPV was 100.00 (95% CI, 98.68-100.00) when only malabsorption symptoms were used instead of any symptom (n = 278). Inclusion of HLA analyses did not increase accuracy. Findings from central laboratories differed greatly for patients with lower levels of antibodies, but when levels of TGA-IgA were 10-fold or more the ULN, PPVs ranged from 99.63 (95% CI, 98.67-99.96) to 100.00 (95% CI, 99.23-100.00). CONCLUSIONS: Children can be accurately diagnosed with celiac disease without biopsy analysis. Diagnosis based on level of TGA-IgA 10-fold or more the ULN, a positive result from the EMA tests in a second blood sample, and the presence of at least 1 symptom could avoid risks and costs of endoscopy for more than half the children with celiac disease worldwide. HLA analysis is not required for accurate diagnosis. Clinical Trial Registration no: DRKS00003555.
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Autoanticorpos/sangue , Doença Celíaca/diagnóstico , Doença Celíaca/imunologia , Proteínas de Ligação ao GTP/imunologia , Imunoglobulina A/sangue , Intestino Delgado/imunologia , Transglutaminases/imunologia , Adolescente , Biomarcadores/sangue , Biópsia , Doença Celíaca/sangue , Doença Celíaca/genética , Criança , Pré-Escolar , Europa (Continente) , Feminino , Antígenos HLA-DQ/genética , Antígenos HLA-DQ/imunologia , Humanos , Lactente , Intestino Delgado/patologia , Masculino , Oriente Médio , Técnicas de Diagnóstico Molecular , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Proteína 2 Glutamina gama-Glutamiltransferase , Reprodutibilidade dos Testes , Testes SorológicosRESUMO
During food fermentation processes like cheese ripening, lactic acid bacteria (LAB) encounter long periods of nutrient limitation leading to slow growth. Particular LAB survive these periods while still contributing to flavour formation in the fermented product. In this study the dairy Lactococcus lactis biovar diacetylactis FM03-V1 is grown in retentostat cultures to study its physiology and aroma formation capacity at near-zero growth rates. During the cultivations, the growth rate decreased from 0.025 h-1 to less than 0.001 h-1 in 37 days, while the viability remained above 80%. The maintenance coefficient of this dairy strain decreased by a factor 7â¯at near-zero growth rates compared to high growth rates (from 2.43⯱â¯0.35 to 0.36⯱â¯0.03â¯mmol ATP.gDW-1.h-1). In the retentostat cultures, 62 different volatile organic compounds were identified by HS SPME GC-MS. Changes in aroma profile resembled some of the biochemical changes occurring during cheese ripening and reflected amino acid catabolism, metabolism of fatty acids and conversion of acetoin into 2-butanone. Analysis of complete and cell-free samples of the retentostat cultures showed that particular lipophilic compounds, mainly long-chain alcohols, aldehydes and esters, accumulated in the cells, most likely in the cell membranes. In conclusion, retentostat cultivation offers a unique tool to study aroma formation by lactic acid bacteria under industrially relevant growth conditions.
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Queijo/microbiologia , Lactococcus lactis/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Queijo/análise , Fermentação , Aromatizantes/química , Aromatizantes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lactococcus lactis/crescimento & desenvolvimento , Odorantes/análise , Paladar , Compostos Orgânicos Voláteis/químicaRESUMO
OBJECTIVE: Antibodies to cell surface central nervous system proteins help to diagnose conditions which often respond to immunotherapies. The assessment of antibody assays needs to reflect their clinical utility. We report the results of a multicentre study of aquaporin (AQP) 4 antibody (AQP4-Ab) assays in neuromyelitis optica spectrum disorders (NMOSD). METHODS: Coded samples from patients with neuromyelitis optica (NMO) or NMOSD (101) and controls (92) were tested at 15 European diagnostic centres using 21 assays including live (n=3) or fixed cell-based assays (n=10), flow cytometry (n=4), immunohistochemistry (n=3) and ELISA (n=1). RESULTS: Results of tests on 92 controls identified 12assays as highly specific (0-1 false-positive results). 32 samples from 50 (64%) NMO sera and 34 from 51 (67%) NMOSD sera were positive on at least two of the 12 highly specific assays, leaving 35 patients with seronegative NMO/spectrum disorder (SD). On the basis of a combination of clinical phenotype and the highly specific assays, 66 AQP4-Ab seropositive samples were used to establish the sensitivities (51.5-100%) of all 21 assays. The specificities (85.8-100%) were based on 92 control samples and 35 seronegative NMO/SD patient samples. CONCLUSIONS: The cell-based assays were most sensitive and specific overall, but immunohistochemistry or flow cytometry could be equally accurate in specialist centres. Since patients with AQP4-Ab negative NMO/SD require different management, the use of both appropriate control samples and defined seronegative NMOSD samples is essential to evaluate these assays in a clinically meaningful way. The process described here can be applied to the evaluation of other antibody assays in the newly evolving field of autoimmune neurology.
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Aquaporina 4/sangue , Autoanticorpos/sangue , Neuromielite Óptica/sangue , Aquaporina 4/imunologia , Autoanticorpos/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Imuno-Histoquímica/métodos , Neuromielite Óptica/imunologia , Sensibilidade e EspecificidadeRESUMO
Celiac disease (CD) is characterized by an inappropriate immunological reaction against gluten driven by gluten-specific CD4+ T cells. We screened 25 proteases and tested 10 for their potential to degrade gluten in vitro. Five proteases were further tested for their ability to prevent the proliferative response by a gluten-specific CD4+ T cell clone and seven gluten-reactive T cell lines to protease-digested gluten peptides. A proline-specific endo-peptidase from Aspergillus niger (AnP2) was particularly efficient at diminishing proliferation after stimulation with cleaved antigen, and could completely block the response against both native and deamidated gluten peptides. We found that AnP2 was efficient down to a 1:64 protease:substrate ratio (w:w). When AnP2 was tested in assays using seven gluten-reactive T cell lines from individual CD patients (three adults and four children), the response to gluten was diminished in all cases. Our study indicates a therapeutic benefit of AnP2 to CD patients.
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Linfócitos T CD4-Positivos/imunologia , Endopeptidases/imunologia , Proteínas Fúngicas/imunologia , Glutens/imunologia , Peptídeos/imunologia , Adulto , Sequência de Aminoácidos , Aspergillus niger/enzimologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Doença Celíaca/imunologia , Doença Celíaca/patologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Criança , Células Clonais/efeitos dos fármacos , Células Clonais/imunologia , Eletroforese em Gel de Poliacrilamida , Endopeptidases/metabolismo , Endopeptidases/farmacologia , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/farmacologia , Glutens/química , Glutens/metabolismo , Humanos , Intestinos/imunologia , Dados de Sequência Molecular , Peptídeos/metabolismo , Especificidade por SubstratoRESUMO
We report an infant of consanguineous parents of Turkish decent with a novel immunodeficiency associated with homozygosity for a nonsense mutation of the gene encoding Inhibitor of nuclear factor kappa-B (NF-κB) kinase subunit beta (IKKß). At five months, she presented with respiratory insufficiency and Pneumocystis jirovecii pneumonia which was successfully treated. At nine months, iatrogenic systemic infection with Mycobacterium bovis was found and eventually led to her death at age 14 months. Laboratory findings were reminiscent of hyper-IgM syndrome, but genetic testing gave no explanation before whole exome sequencing revealed a novel mutation abrogating signaling through the canonical NF-κB pathway.
Assuntos
Códon sem Sentido , Quinase I-kappa B/genética , Síndromes de Imunodeficiência/genética , Evolução Fatal , Feminino , Humanos , Síndromes de Imunodeficiência/complicações , Lactente , Mycobacterium bovis , Pneumocystis carinii , Pneumonia por Pneumocystis/complicações , Insuficiência Respiratória/complicações , Tuberculose/complicações , Tuberculose/patologia , Vacinação/efeitos adversosRESUMO
Growth of Listeria innocua at 9 °C was investigated in white cheeses manufactured from ultra-filtrate milk concentrate added varying amounts of skimmed milk powder, NaCl and glucono-delta-lactone. Characterization of the white cheese structures was performed using nuclear magnetic resonance (NMR) T2 relaxation parameters (relaxation times constants, relative areas and width of peaks) and their applicability as predictive factors for maximum specific growth rate, âµ(max) and log-increase in 6 weeks of L. innocua was evaluated by polynomial modeling. Inclusion of NMR parameters was able to increase the goodness-of-fit of two basic models; one having pH, undissociated gluconic acid (GA(u), mM) and NaCl (% w/v) as predictive factors and another having pH, GA(u) and a(w) as predictive factors. However, the best model fit was observed using âµ(max) as response for the model including pH, GA(u), aw and Width T21 revealing the lowest relative root mean squared errors of 14.0%. As the T2 relaxation population T21 is assigned to represent immobilized bulk water protons and the width T21 the heterogeneity of this water population, growth of L. innocua in white cheese seemed to be dependent on the heterogeneity of the immobilized bulk water present in cheese.
Assuntos
Queijo/análise , Queijo/microbiologia , Listeria/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Modelos Biológicos , Água/análiseRESUMO
BACKGROUND: Transient elastography (TE) is a new noninvasive method to assess the degree of liver fibrosis by measuring liver stiffness. The objective of this study was to determine whether increased liver stiffness in patients admitted to medical wards was associated with increased 30-day mortality. MATERIALS AND METHODS: A prospective cohort study at the medical admissions ward at Odense University Hospital, Denmark, covering a population of 300 000 inhabitants. Consecutive patients ≥ 18 years of age were examined by TE (Fibroscan) at admission. Outcome measure was 30-day mortality. RESULTS: Among 568 patients admitted during 24 days, 289 (50·8%) were included in the study, 212 (73·4%) with valid TE measurement. Increased liver stiffness (TE value > 8 kPa) was found in 22·6% (48/212). This was independently associated with cirrhosis of the liver (P < 0·001) and congestive heart failure (CHF) (P < 0·001). The estimated prevalence of cirrhosis was 7% (95% CI 4-11%). The 30-day mortality among patients with TE value > 8 kPa was 20·8% (10/48, 95%CI 10·5-35·0%) compared to patients with TE value ≤ 8 kPa 3·7% (6/164, 95%CI 1·3-7·8%) (P < 0·001), and TE value > 8 kPa was an independent predictor of death. CONCLUSIONS: Elevated TE value at admission is associated with increased mortality, cirrhosis of the liver and CHF. This information may potentially be used to improve the outcome of high-risk patients admitted to hospital.