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1.
BMC Microbiol ; 21(1): 228, 2021 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-34407769

RESUMEN

BACKGROUND: Targeted metagenomics and IS-Pro method are two of the many methods that have been used to study the microbiome. The two methods target different regions of the 16 S rRNA gene. The aim of this study was to compare targeted metagenomics and IS-Pro methods for the ability to discern the microbial composition of the lung microbiome of COPD patients. METHODS: Spontaneously expectorated sputum specimens were collected from COPD patients. Bacterial DNA was extracted and used for targeted metagenomics and IS-Pro method. The analysis was performed using QIIME2 (targeted metagenomics) and IS-Pro software (IS-Pro method). Additionally, a laboratory cost per isolate and time analysis was performed for each method. RESULTS: Statistically significant differences were observed in alpha diversity when targeted metagenomics and IS-Pro methods' data were compared using the Shannon diversity measure (p-value = 0.0006) but not with the Simpson diversity measure (p-value = 0.84). Distinct clusters with no overlap between the two technologies were observed for beta diversity. Targeted metagenomics had a lower relative abundance of phyla, such as the Proteobacteria, and higher relative abundance of phyla, such as Firmicutes when compared to the IS-Pro method. Haemophilus, Prevotella and Streptococcus were most prevalent genera across both methods. Targeted metagenomics classified 23 % (144/631) of OTUs to a species level, whereas IS-Pro method classified 86 % (55/64) of OTUs to a species level. However, unclassified OTUs accounted for a higher relative abundance when using the IS-Pro method (35 %) compared to targeted metagenomics (5 %). The two methods performed comparably in terms of cost and time; however, the IS-Pro method was more user-friendly. CONCLUSIONS: It is essential to understand the value of different methods for characterisation of the microbiome. Targeted metagenomics and IS-Pro methods showed differences in ability in identifying and characterising OTUs, diversity and microbial composition of the lung microbiome. The IS-Pro method might miss relevant species and could inflate the abundance of Proteobacteria. However, the IS-Pro kit identified most of the important lung pathogens, such as Burkholderia and Pseudomonas and may work in a more diagnostics-orientated setting. Both methods were comparable in terms of cost and time; however, the IS-Pro method was easier to use.


Asunto(s)
Pulmón/microbiología , Metagenómica/métodos , Metagenómica/normas , Microbiota/genética , Programas Informáticos/normas , Anciano , Anciano de 80 o más Años , ADN Bacteriano/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , ARN Ribosómico 16S/genética , Esputo/microbiología
2.
J Antimicrob Chemother ; 75(4): 896-902, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-31953941

RESUMEN

INTRODUCTION: Klebsiella pneumoniae with OXA-48-like enzymes were introduced into Tshwane Tertiary Hospital (TTH) (Pretoria, South Africa) during September 2015, causing nosocomial outbreaks. METHODS: PCR methodologies and WGS were used to characterize K. pneumoniae with carbapenemases (n = 124) from TTH (July 2015-December 2016). RESULTS: PCR was used to track K. pneumoniae ST307 with OXA-181 among 60% of carbapenemase-positive isolates in different wards/units over time and showed the transmission of IncX3 plasmids to other K. pneumoniae clones. WGS identified different ST307 clades: 307_OXA181 (consisting of two lineages, A and B) with OXA-181 on IncX3 plasmids (named p72_X3_OXA181) and clade 307_VIM with VIM-1 on IncFII plasmids. Clade 307_OXA181 lineage B was responsible for the rapid increase and transmission of OXA-181 K. pneumoniae in various wards/units throughout TTH, while the numbers of clade 307_OXA181 lineage A and clade 307_VIM remained low. Separate outbreaks were due to K. pneumoniae ST17 and ST29 with p72_X3_OXA181 plasmids. CONCLUSIONS: The high-risk clone K. pneumoniae ST307 with OXA-181 rapidly spread to different wards/units despite infection and prevention measures. ST307 clades and lineages seemingly acted differently in outbreak situations. This study also highlighted the threat of promiscuous plasmids such as p72_X3_OXA181.


Asunto(s)
Infecciones por Klebsiella , Klebsiella pneumoniae , Proteínas Bacterianas/genética , Células Clonales , Atención a la Salud , Humanos , Infecciones por Klebsiella/epidemiología , Klebsiella pneumoniae/genética , Plásmidos/genética , Sudáfrica , beta-Lactamasas/genética
3.
Cogn Affect Behav Neurosci ; 19(3): 715-725, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30357659

RESUMEN

Previous research has established a role for the norepinephrine (NE)/stress system in individual differences in biases to attend to reward or punishment. Outstanding questions concern its role in the flexibility with which such biases can be changed. The goal of this preregistered study was to examine the role of the NE/stress system in the degree to which biases can be trained along the axis of valence in the direction of reward. Participants genotyped for a common deletion variant of ADRA2b (linked to altered NE availability) experienced either an acute stress induction or a control procedure. Following stress induction, a "bias probe" task was presented before and after training. In the bias probe task, participants made forced choice judgments (happy or angry) on emotional faces with varying degrees of ambiguity. For bias training, participants viewed unambiguously angry faces in a task exploiting visual adaptation effects. The results revealed an overall shift from a slightly positive bias in categorizing faces pretraining to a more positive bias after training. Carriers of the deletion variant overall showed a more positive bias than did the noncarriers. Follow-up analyses showed that pretraining bias was a significant predictor of bias change, with those who showed a more negative bias preadaptation changing more in a positive direction. Critically, this effect was observed under control but not under stress conditions. These results suggest that the NE/stress system plays an important role in influencing trait-like biases as well as short-term changes in the tendency to perceive ambiguous stimuli as being more rewarding than threatening.


Asunto(s)
Adaptación Psicológica/fisiología , Expresión Facial , Reconocimiento Facial/fisiología , Norepinefrina/fisiología , Personalidad/fisiología , Recompensa , Estrés Psicológico/fisiopatología , Adulto , Ira/fisiología , Femenino , Felicidad , Humanos , Masculino , Receptores Adrenérgicos alfa 2/genética , Adulto Joven
4.
Neurobiol Learn Mem ; 145: 84-93, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28893670

RESUMEN

Addiction is increasingly discussed asa disorder of associative learning processes, with both operant and classical conditioning contributing to the development of maladaptive habits. Stress has long been known to promote drug taking and relapse and has further been shown to shift behavior from goal-directed actions towards more habitual ones. However, it remains to be investigated how acute stress may influence simple associative learning processes that occur before a habit can be established. In the present study, healthy young adults were exposed to either acute stress or a control condition half an hour before performing simple classical and operant conditioning tasks. Psychophysiological measures confirmed successful stress induction. Results of the operant conditioning task revealed reduced instrumental responding under delayed acute stress that resembled behavioral responses to lower levels of reward. The classical conditioning experiment revealed successful conditioning in both experimental groups; however, explicit knowledge of conditioning as indicated by stimulus ratings differentiated the stress and control groups. These findings suggest that operant and classical conditioning are differentially influenced by the delayed effects of acute stress with important implications for the understanding of how new habitual behaviors are initially established.


Asunto(s)
Aprendizaje por Asociación , Hábitos , Estrés Psicológico , Adulto , Presión Sanguínea , Condicionamiento Clásico , Condicionamiento Operante , Femenino , Frecuencia Cardíaca , Humanos , Hidrocortisona/análisis , Masculino , Adulto Joven
5.
Sex Transm Infect ; 93(6): 410-415, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28143901

RESUMEN

OBJECTIVES: The purpose of this cross-sectional study was to assess Atopobium vaginae and Gardnerella vaginalis concentrations in pregnant women of different age groups, gestational age groups, vaginal flora categories and HIV status, and also to determine which DNA concentrations best discriminated between bacterial vaginosis (BV)-positive and non-BV categories. METHODS: Self-collected vaginal swabs were obtained from 220 pregnant women attending an antenatal clinic in Pretoria, Gauteng, South Africa, from July 2012 to December 2012. BV was detected with the Nugent scoring system, and A. vaginae and G. vaginalis DNA was quantified with a multiplex quantitative real-time PCR assay. RESULTS: Median concentrations of A. vaginae and G. vaginalis were not significantly different among various age groups (A. vaginae p=0.98 and G. vaginalis p=0.18) or different trimesters (A. vaginae p=0.31 and G. vaginalis p=0.19), but differed significantly among the vaginal flora categories (A. vaginae p<0.001 and G. vaginalis p<0.001) and HIV status (A. vaginae p<0.001 and G. vaginalis p=0.004). The presence of A. vaginae (OR=5.8; 95% CI 1.34 to 25.21 and p value=0.02) but not that of G. vaginalis (OR=1.90; 95% CI 0.81 to 4.43 and p value=0.14) was associated with HIV infection. An A. vaginae DNA concentration of ≥107 copies/mL together with a positive G. vaginalis result (≥100 copies/mL) best discriminated between BV-positive (39/220) and non-BV categories (181/220) with a sensitivity of 85% (95% CI 0.70 to 0.94) and a specificity of 82% (95% CI 0.76 to 0.88). CONCLUSIONS: A. vaginae and G. vaginalis were present in high numbers and concentrations in this pregnant cohort. Threshold concentrations should be established for specific populations to ensure sensitive molecular assays for BV detection.


Asunto(s)
Actinobacteria/aislamiento & purificación , Gardnerella vaginalis/aislamiento & purificación , Complicaciones Infecciosas del Embarazo/microbiología , Vaginosis Bacteriana/microbiología , Adulto , Antiinfecciosos/uso terapéutico , Carga Bacteriana , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Complicaciones Infecciosas del Embarazo/epidemiología , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa , Sudáfrica/epidemiología , Vagina/microbiología , Vaginosis Bacteriana/tratamiento farmacológico , Vaginosis Bacteriana/epidemiología
6.
Horm Metab Res ; 48(10): 623-629, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27607246

RESUMEN

Autoimmune Thyroiditis (AIT) is the most common autoimmune disease, which is characterized by cellular and humoral immunity leading to thyroid destruction. The impact of the humoral immunity on the risk to develop hypothyroidism has not exactly been defined yet. The aim of the present study was to investigate the association between thyroid antibody levels and the risk for developing hypothyroidism. In this retrospective study, 335 untreated AIT patients were enrolled. Anti-thyroperoxidase (TPO) antibodies, anti-thyroglobulin (Tg) antibodies (Abs), and the TSH level were measured. Patients with TPO-Ab levels>500 IU/ml showed a moderately increased risk of having elevated TSH levels [p=0.0023; relative risk (95% confidence interval): 1.343 (1.108-1.627)] compared to those below this threshold. AIT patients with TPO- or Tg-Abs<100 IU/ml and between 100-500 IU/ml had no significantly different TSH levels. Presence of Tg-Abs alone or in combination with TPO-Abs did not help to increase the sensitivity to identify patients at risk. Long term follow-up of AIT patients with high TPO-Abs level (>500 IU/ml) showed an increase of TSH levels (mean: 0.5 mIU/l; range: 2.52±2.73 to 3.02±3.05 mIU/l; p=0.0420). Still, these patients remained euthyroid. Our data indicate largely elevated levels of TPO-Abs being associated with a moderately increased risk of developing hypothyroidism.


Asunto(s)
Anticuerpos Antiidiotipos/sangre , Autoanticuerpos/sangre , Autoantígenos/inmunología , Hipotiroidismo/sangre , Yoduro Peroxidasa/inmunología , Proteínas de Unión a Hierro/inmunología , Tiroiditis Autoinmune/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antiidiotipos/inmunología , Autoanticuerpos/inmunología , Autoantígenos/sangre , Femenino , Estudios de Seguimiento , Humanos , Hipotiroidismo/etiología , Yoduro Peroxidasa/sangre , Proteínas de Unión a Hierro/sangre , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tiroiditis Autoinmune/complicaciones , Tiroiditis Autoinmune/inmunología , Adulto Joven
7.
Horm Metab Res ; 48(12): 795-801, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27923250

RESUMEN

Until recently, stimulating TSH receptor autoantibodies (sTRAbs) could only be measured by bioassays. A new assay system, which directly detects sTRAb in sera by applying bridge technology, has been established and is now available as automated chemiluminescence (bridge) immunoassay. We evaluated the automated bridge assay in clinical routine and compared it with a conventional automated TRAb assay (competition assay). Altogether, 226 Graves' disease (GD), 57 autoimmune thyroiditis, 74 non-autoimmune nodular goiter and 49 thyroid cancer patients, as well as 41 healthy controls were retrospectively evaluated. ROC plot analysis based on sera of newly diagnosed GD patients revealed an area under curve of 0.99 (95% CI: 0.99-1.0) indicating a high assay sensitivity and specificity. The highest sensitivity (100%) and specificity (99%) were seen at a cut-off level of 0.55 IU/l. The calculated positive predictive value was 94%, whereas the negative was 100%. Applying a ROC plot-derived cut-off of≥0.30 IU/l, derived from sera of GD patients already receiving antithyroid drug therapy for≤6 months, the sensitivity was 99% whereas the specificity was 98%. Detailed comparison of both assay systems used revealed a slightly different distribution of sTRAb and TRAb. Measurement of sTRAb during follow-up revealed a steady decline over one year of follow-up. In summary, our results demonstrate that the new automated bridge assay system for detecting sTRAb has a high sensitivity and specificity for diagnosing GD and to discriminate from other thyroid diseases, respectively. Our study, however, does not provide full evidence that the bridge assay is specific for sTRAb only.


Asunto(s)
Autoanticuerpos/biosíntesis , Inmunoensayo/métodos , Receptores de Tirotropina/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Automatización , Femenino , Estudios de Seguimiento , Enfermedad de Graves/sangre , Enfermedad de Graves/diagnóstico , Enfermedad de Graves/inmunología , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Tiroxina/sangre , Factores de Tiempo , Adulto Joven
8.
J Dairy Sci ; 98(9): 6256-69, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26188567

RESUMEN

The objectives of this study were to examine the diversity of Staphylococcus spp. recovered from bovine intramammary infections and humans working in close contact with the animals and to evaluate the susceptibility of the staphylococcal isolates to different antimicrobials. A total of 3,387 milk samples and 79 human nasal swabs were collected from 13 sampling sites in the KwaZulu-Natal province of South Africa. In total, 146 Staph. aureus isolates and 102 coagulase-negative staphylococci (CNS) were recovered from clinical and subclinical milk samples. Staphylococcusaureus was isolated from 12 (15.2%) of the human nasal swabs and 95 representative CNS were recovered for further characterization. The CNS were identified using multiplex-PCR assays, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and tuf gene sequencing. Seven Staphylococcus spp. were identified among the CNS of bovine origin, with Staph.chromogenes (78.4%) predominating. The predominant CNS species recovered from the human nasal swabs was Staph.epidermidis (80%) followed by Staph.chromogenes (6.3%). The antimicrobial susceptibility of all staphylococcal isolates was evaluated using disk diffusion and was supplemented by screening for specific antimicrobial resistance genes. Ninety-eight (67.1%) Staph.aureus isolates of bovine origin were pansusceptible; 39 (26.7%) isolates were resistant to a single class, and 7 (4.8%) isolates were resistant to 2 classes of antimicrobials. Two Staph. aureus (1.4%) isolates were multidrug-resistant. Resistance to penicillin was common, with 28.8% of the bovine and 75% of the human Staph. aureus isolates exhibiting resistance. A similar observation was made with the CNS, where 37.3% of the bovine and 89.5% of the human isolates were resistant to penicillin. Multidrug-resistance was common among the human CNS, with 39% of the isolates exhibiting resistance to 3 or more classes of antimicrobials. The antimicrobial susceptibility results suggest that resistance among staphylococci causing bovine intramammary infections in South Africa is uncommon and not a significant cause for concern. In contrast, antimicrobial resistance was frequently observed in staphylococcal isolates of human origin, highlighting a possible reservoir of resistance genes. Continued monitoring of staphylococcal isolates is warranted to monitor changes in the susceptibility of isolates to different classes of antimicrobials.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple , Genes Bacterianos , Mastitis Bovina/tratamiento farmacológico , Staphylococcus/aislamiento & purificación , Animales , Proteínas Bacterianas/genética , Biodiversidad , Bovinos , Femenino , Humanos , Leche/microbiología , Proteínas de Unión a las Penicilinas/genética , Sudáfrica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/veterinaria , Staphylococcus/clasificación , Staphylococcus/efectos de los fármacos , Staphylococcus/genética , Staphylococcus aureus/aislamiento & purificación
9.
Diabetes Obes Metab ; 16(5): 451-6, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24251641

RESUMEN

AIMS: Any differences observed between natural glucagon-like peptide-1 (GLP-1) and studies obtained with analogues might call for renewed considerations concerning the use and design of such analogues. Thus, we aimed to evaluate the dose-response relationship of recombinant glucagon-like peptide-1 (7-36) amide (rGLP-1) administered by continuous subcutaneous infusion (CSCI) in subjects with type 2 diabetes. METHODS: We compared the efficacy and safety of three doses of recombinant GLP-1, ranging from 1.25 to 5.0 pmol/kg/min (pkm) and placebo, given by continuous subcutaneous infusion over 3 months in combination with metformin and sulphonylurea (SU), to lower haemoglobin A1c (HbA1c), fasting plasma glucose and weight in 95 type 2 diabetes patients with inadequate glycaemic control. RESULTS: The mean decreases in HbA1c at endpoint (week 12) were significantly greater for all three rGLP-1 dose groups when each was compared with the placebo group, with the greatest decrease occurring in the 5.0 pkm dose group (-1.3%, s.d. ± 0.18, p < 0.001). The mean decreases in fasting plasma glucose from baseline to endpoint were significantly greater for all three rGLP-1 dose groups than for the placebo group, with the greatest decrease occurring in the 5.0 pkm dose group (-26.0 mg/dl, s.d. ± 8.5, p = 0.02). Body weight was significantly reduced by 1.8 kg (s.d. ± 1.3) in the 1.25 pkm dose group only (p = 0.04). CONCLUSIONS: Administration of rGLP-1 by CSCI over a 12-week period in combination with metformin and an SU had a dose dependent effect in lowering HbA1c and fasting plasma glucose. However, administration of rGLP-1 by CSCI may be less effective with respect to lowering of body weight compared with the daily and once weekly analogues.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Péptido 1 Similar al Glucagón/análogos & derivados , Hipoglucemiantes/administración & dosificación , Infusiones Subcutáneas , Metformina/administración & dosificación , Compuestos de Sulfonilurea/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Diabetes Mellitus Tipo 2/sangre , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Hemoglobina Glucada/efectos de los fármacos , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
10.
Horm Metab Res ; 45(8): 599-604, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23589231

RESUMEN

Autoimmune Addison's disease (AD) is a rare but potentially life threatening disease. The exact etiology of the immune response to the adrenal gland is still unknown. MicroRNAs (miRNAs) critically control gene-expression and play an important role in regulating the immune response. The aim of this study was to determine key immunoregulatory miRNAs influencing autoimmune adrenal insufficiency. For this purpose selected miRNAs were amplified by a semiquantitative SYBR Green PCR from blood mononuclear cells and after purification from CD4+ and CD 8+ cells of 6 patients with autoimmune adrenal insufficiency and 10 healthy controls. In CD4+ T-cells miRNA 181a*_1 (18.02 in AD vs. 11.99 in CG, p=0.0047) is significantly increased whereas miRNA 200a_1 (12.48 in AD vs. 19.40 in CG, p=0.0003) and miRNA 200a_2* (8.59 in AD vs. 17.94 in CG, p=0.0160) are significantly decreased. miRNA 200a_1 (12.37 in AD group vs. 18.12 in control group, p=0.001) and miRNA 200a_2* (10.72 in AD group vs. 17.84 in control group, p=0.022) are also significantly decreased in CD8+ T-cells. This study could show for the first time a significant change of three defined miRNAs in PBMCs, CD4+, and CD8+ T-cells of autoimmune AD patients in vivo. These data may help to better understand the cause of the autoimmune processes leading to autoimmune AD. They extend our very limited knowledge concerning miRNAs in autoimmune Addison's disease.


Asunto(s)
Enfermedad de Addison/genética , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , MicroARNs/genética , Enfermedad de Addison/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Humanos , Masculino , MicroARNs/inmunología , Persona de Mediana Edad , Adulto Joven
11.
Horm Metab Res ; 45(1): 74-7, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22972181

RESUMEN

Graves' disease (GD) and Hashimoto's thyroiditis (HT) are the most common autoimmune thyroid diseases (AITDs) affecting up to 5% of the general population. In Caucasians HT has a prevalence of up to 4.60% and GD a prevalence of 1-2%. The aim of this study was to investigate the association between HLA-A2 and the AITDs GD and HT among Caucasians. HLA alleles of 33 patients with GD and 75 patients with HT were determined by serological typing. The frequency of HLA A2 was significantly reduced in GD (p=0.033) but not in HT (p=n.s.) as compared to control samples. In individuals positive for HLA-A2 odds ratio for protection from GD was found to be 2.8. This study supports the hypothesis that genetic predisposition to GD is not restricted to MHC class II molecules. The significant negative association between HLA A2 and GD supports the hypothesis that MHC class I genes may be relevant for the protection from GD. In contrast the nonsignificant results for HT indicate that this association may not apply to AITDs in general.


Asunto(s)
Predisposición Genética a la Enfermedad , Enfermedad de Graves/genética , Enfermedad de Graves/inmunología , Antígeno HLA-A2/genética , Enfermedad de Hashimoto/genética , Enfermedad de Hashimoto/inmunología , Población Blanca/genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Fenotipo , Factores de Riesgo , Adulto Joven
12.
Horm Metab Res ; 45(6): 401-7, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23386414

RESUMEN

Over the past decade a number of murine models of Graves' disease (GD) have been described. The full symptom complex, including typical orbital changes, however, could not yet be induced. In this report, we examined the influence of modified immunization protocols on orbital pathology. C57BL/6 and BALB/c mice were immunized against the human TSH receptor (TSHR), using either a TSHR encoding plasmid or a TSHR A-subunit adenovirus. Prior to immunization with the TSHR plasmid, regulatory T cells were depleted in one group of each strain. TSHR-stimulating antibodies (TSAbs) were evaluated and orbits were stained immunohistochemically for F4/80, uncoupling protein-1 (UCP-1) and the TSHR. We found that after depletion of regulatory T cells, incidence of TSAb was increased in TSHR plasmid immunized C57BL/6 mice. Examination of early immunized mice showed no antibody production. However, a TSHR epitope-specific cellular immune response could be detected by tetramer-analyses. Adenoviral immunization lead to TSAb production in all but one animal. Analysis of F4/80 positive cells in retrobulbar fat revealed no significant macrophage infiltration in the orbits of immunized mice. Immunohistochemical staining shows co-localization of F4/80 positive cells, UCP-1 and the TSHR in retrobulbar fat. Though targets for TSHR autoimmunity could clearly be shown, immunization methods were not efficient enough to cause clear signs of orbital inflammation.


Asunto(s)
Tejido Adiposo/metabolismo , Enfermedad de Graves/genética , Canales Iónicos/genética , Proteínas Mitocondriales/genética , Órbita/metabolismo , Receptores de Tirotropina/genética , Animales , Modelos Animales de Enfermedad , Femenino , Enfermedad de Graves/metabolismo , Humanos , Canales Iónicos/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Proteínas Mitocondriales/metabolismo , Transporte de Proteínas , Receptores de Tirotropina/metabolismo , Proteína Desacopladora 1
13.
Z Rheumatol ; 71(9): 798-800, 2012 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-23138557

RESUMEN

The Fc fragments of pathogenic IgG autoantibodies in patients with rheumatoid arthritis are low-galactosylated and low-sialylated. In contrast, high-galactosylated and high-sialylated antigen-specific IgG antibodies are sufficient to inhibit a pro-inflammatory immune response in an antigen-specific manner and might be a promising therapeutic tool to re-establish tolerance against defined self-antigens in autoimmune patients.


Asunto(s)
Artritis Reumatoide/inmunología , Autoanticuerpos/inmunología , Productos Finales de Glicación Avanzada/inmunología , Inmunidad Innata/inmunología , Inmunoglobulina G/inmunología , Modelos Inmunológicos , Animales , Humanos
14.
Heliyon ; 8(12): e12177, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36510570

RESUMEN

Right from the start of the COVID pandemic in January 2020, the entire tourism sector was put under immense pressure because of its assumed role in SARS-CoV-2 transmission and infection dynamics. Based on reports of single superspreading events in the early days of the pandemic, the hotel industry appeared in a bad light that impaired a strategic risk-assessment of existing transmission risks between tourists and employees. We prospectively analysed samples of 679 employees of 21 hotels and restaurants from July 2020 to December 2020, a time during which more than 1.5 million tourists visited the Lübeck/Ostholstein Baltic Sea vacation area in Northern Germany. Employees were tested up to three times for an acute SARS-CoV-2 infection (PCR from nasopharyngeal swabs) and the presence of SARS-CoV-2 specific antibodies, and were asked to complete a short questionnaire. Despite the massive increase in tourist influx, no significant increase in SARS-CoV-2 cases was observed amongst employees of the tourism sector from July to September 2020. In a cluster-outbreak analysis of 104 study participants of one single hotel in the Lübeck/Ostholstein region in October 2020 being employed in the low-wage sector "housekeeping" could be determined as major risk factor for becoming infected. In conclusion, in a low incidence setting, touristic activities are safe under COVID-related hygiene measures for both the local population and employees of the tourism sector. Whereas, the field of work is a potential risk factor for increased infection dynamics.

15.
Curr Opin Cell Biol ; 8(4): 484-9, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8791455

RESUMEN

The proper targeting and clustering of neurotransmitter receptors at appropriate postsynaptic sites are principal requirements for the formation of functional synapses. Recently, new studies have begun to elucidate the mechanisms underlying the targeting and clustering of glutamate receptors at excitatory synapses in the brain. Members of the SAP90/PSD-95 family of proteins have emerged as potential regulators of glutamate-receptor membrane distribution. Further, targeting motifs within glutamate receptor subunits have been identified. These findings provide important clues in the effort to understand the molecular features of synaptic organization.


Asunto(s)
Compartimento Celular , Receptores de Glutamato/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapsis/metabolismo , Transporte Biológico , Modelos Biológicos
16.
Horm Metab Res ; 43(12): 890-6, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21971962

RESUMEN

During the last 30 years the incidence of neuroendocrine tumors has increased considerably and the overall 5-year survival rate has not changed substantially. Conventional therapeutic approaches appear to show an unsatisfactory effect in the more insidious forms of malignancies. Hence, attempts were made to direct the patient's own immune system against cancer by vaccinating against different tumor antigens. Up to date, only sporadic achievements were demonstrated in the majority cases of vaccination trials. One of the main hindrances to a successful vaccination comprises tumor-immune-escape mechanisms. This review focuses on the current knowledge concerning tumor immunoevasion strategies and the immune system in neuroendocrine tumors.


Asunto(s)
Sistema Inmunológico/inmunología , Tumores Neuroendocrinos/inmunología , Humanos , Inmunidad/inmunología , Células Asesinas Naturales/inmunología , Tumores Neuroendocrinos/patología , Linfocitos T/inmunología
19.
Diabetes Obes Metab ; 13(7): 639-43, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21362122

RESUMEN

AIM: To evaluate the dose-response relationship of the recombinant glucagon-like peptide-1 (7-36) amide (rGLP-1) administered by continuous subcutaneous infusion (CSCI) in subjects with type 2 diabetes, with respect to reductions in fasting, postprandial and 11-h serum glucose profiles. METHODS: In a double-blind, parallel, placebo-controlled trial, 47 patients were randomized to placebo or rGLP-1 (1.25, 2.5, 5.0 or 8.5 pmol/kg/min) by CSCI for 7 days. On day 1 (pretreatment) and on day 8, patients underwent monitoring of fasting, postprandial, and 11-h profiles of glucose and hormones. RESULTS: Fasting serum glucose decreased by 76.2, 53.9, 37.0 and 22.7 mg/dl for the 8.5, 5.0, 2.5 and 1.25 pmol/kg/min rGLP-1 groups, respectively, compared to a decrease of 1.1 mg/dl for placebo (p = 0.0002, 0.005, 0.064 and 0.27, respectively). Mean 11-h serum glucose area under the curve decreased by 36.3, 23.3, 16.9 and 10.0% for 8.5, 5.0, 2.5 and 1.25 pmol/kg/min rGLP-1, respectively, compared to no change for placebo (p = 0.0001, 0.0019, 0.012 and 0.14, respectively). Mean fasting C-peptide increased dose dependently with rGLP-1 (p = 0.0023 for the highest dose) and decreased with placebo. There were no serious safety concerns and no instances of hypoglycaemia. CONCLUSIONS: rGLP-1 produced continuous improvements in glycaemic control across a broad dose range of up to 8.5 pmol/kg/min.


Asunto(s)
Glucemia/metabolismo , Péptido C/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Péptido 1 Similar al Glucagón/administración & dosificación , Hipoglucemiantes/uso terapéutico , Fragmentos de Péptidos/uso terapéutico , Diabetes Mellitus Tipo 2/sangre , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Péptido 1 Similar al Glucagón/sangre , Humanos , Infusiones Subcutáneas , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/sangre , Placebos , Periodo Posprandial
20.
Sci Rep ; 11(1): 19758, 2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-34611216

RESUMEN

Chronic obstructive pulmonary disease (COPD) is characterised by the occurrence of exacerbations triggered by infections. The aim of this study was to determine the composition of the lung microbiome and lung virome in patients with COPD in an African setting and to compare their composition between the stable and exacerbated states. Twenty-four adult COPD patients were recruited from three hospitals. Sputum was collected and bacterial DNA was extracted. Targeted metagenomics was performed to determine the microbiome composition. Viral DNA and RNA were extracted from selected samples followed by cDNA conversion. Shotgun metagenomics sequencing was performed on pooled DNA and RNA. The most abundant phyla across all samples were Firmicutes and Proteobacteria. The following genera were most prevalent: Haemophilus and Streptococcus. There were no considerable differences for alpha and beta diversity measures between the disease states. However, a difference in the abundances between disease states was observed for: (i) Serratia (3% lower abundance in exacerbated state), (ii) Granulicatella (2.2% higher abundance in exacerbated state), (iii) Haemophilus (5.7% higher abundance in exacerbated state) and (iv) Veillonella (2.5% higher abundance in exacerbated state). Virome analysis showed a high abundance of the BeAn 58058 virus, a member of the Poxviridae family, in all six samples (90% to 94%). This study is among the first to report lung microbiome composition in COPD patients from Africa. In this small sample set, no differences in alpha or beta diversity between stable and exacerbated disease state was observed, but an unexpectedly high frequency of BeAn 58058 virus was observed. These observations highlight the need for further research of the lung microbiome of COPD patients in African settings.


Asunto(s)
Pulmón/microbiología , Microbiota , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/etiología , Anciano , Biodiversidad , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Metagenoma , Metagenómica , Persona de Mediana Edad , Factores de Riesgo , Sudáfrica/epidemiología , Esputo/microbiología
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