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INTRODUCTION: Stratum corneum (SC) is essential for skin barrier function, mitigating water loss and shielding against potentially harmful substances and allergens. The SC's lipid matrix, arranged in a lamellar structure, is integral to its protective role. Our study explores the restoration effects of a multilamellar cream with an acidic pH compared to a basic placebo cream on skin physiology and its interaction with the skin microbiome after stress induction via tape stripping (TS). MATERIALS AND METHODS: In this double-blind study, 14 healthy participants aged 21-58 years were assessed pre- and post-tape stripping, followed by a 14 days application of a multilamellar test cream and a placebo cream with evaluations on days 7, 14 and 17 for sustained effects. Skin physiology was analysed in terms of epidermal barrier function, SC hydration and surface pH. The microbiome was analysed by 16S rRNA amplicon sequencing the 16S rRNA gene using Illumina MiSeq, with subsequent species identification. RESULTS: Our study showed significant improvements in skin barrier repair and SC hydration with verum, particularly after 14 days of application, while both creams initially enhanced stratum corneum hydration. No significant changes in surface-pH were detected. The skin microbiome analysis revealed that TS slightly decreased alpha diversity, a trend that verum significantly reversed, enhancing diversity beyond baseline levels after 14 days. Overall, while both creams contributed to a broader microbial phyla diversity over time, no significant changes in the abundance of specific genera or species were noted between treatments. DISCUSSION AND CONCLUSION: Our study delineates the efficacy of a pH-optimized multilamellar cream in enhancing epidermal barrier recovery and SC hydration post-sequential TS, in contrast to an unstructured basic placebo. Verum cream significantly improved skin barrier function and SC hydration at day 14, with sustained effects evident beyond the treatment period. Furthermore, the multilamellar formulation facilitated the restitution of cutaneous microbiome diversity, a key indicator of healthy skin ecology, underscoring the symbiotic relationship between barrier integrity and microbial composition. These findings underscore the importance of multilamellar emollient structures in dermatological therapeutics, with potential implications for the design of advanced skincare interventions that holistically support cutaneous resilience and homeostasis.
INTRODUCTION: La couche cornée (stratum corneum, SC) est essentielle pour la fonction de barrière cutanée, atténuant la perte d'eau et protégeant contre les substances et allergènes potentiellement nocifs. Disposée selon une structure lamellaire, la matrice lipidique de la SC est constitutive de son rôle protecteur. Notre étude explore les effets de restauration d'une crème multilamellaire à pH acide par rapport à une crème placebo de base sur la physiologie de la peau et son interaction avec le microbiome de la peau après induction de stress via un test tape stripping (TS). MATÉRIELS ET MÉTHODES: Dans cette étude en double aveugle, 14 participants en bonne santé âgés de 21 à 58 ans ont été évalués avant et après tape stipping, puis ont procédé à l'application pendant 14 jours d'une crème test multilamellaire et d'une crème placebo avec des évaluations aux jours 7, 14 et 17 pour les effets durables. La physiologie de la peau a été analysée en termes de fonction de la barrière épidermique, d'hydratation SC et de pH de surface. Le microbiome a été analysé par séquençage de l'amplicon de l'ARNr 16S sur le gène de l'ARNr 16S à l'aide d'Illumina MiSeq, avec identification ultérieure des espèces. RÉSULTATS: Notre étude a montré des améliorations significatives de la réparation de la barrière cutanée et de l'hydratation SC avec le traitement actif, en particulier après 14 jours d'application, tandis que les deux crèmes avaient initialement amélioré l'hydratation de la couche cornée. Aucun changement significatif du pH de surface n'a été détecté. L'analyse du microbiome cutané a révélé que le TS diminuait légèrement la diversité alpha, une tendance qui s'est significativement inversée avec le traitement actif : une amélioration de la diversité audelà des taux initiaux était observée après 14 jours. Dans l'ensemble, bien que les deux crèmes aient contribué à une plus grande diversité des phyla microbiennes au fil du temps, aucune variation significative dans l'abondance de genres ou d'espèces spécifiques n'a été observée entre les traitements. DISCUSSION ET CONCLUSION: Notre étude délimite l'efficacité d'une crème multilamellaire à pH optimisé pour améliorer la réparation de la barrière épidermique et l'hydratation SC après un TS séquentiel, contrairement à un placebo basique non structuré. La crème contenant le traitement actif a significativement amélioré la fonction de barrière cutanée et l'hydratation SC au jour 14, avec des effets durables évidents audelà de la période de traitement. En outre, la formulation multilamellaire a facilité la restitution de la diversité du microbiome cutané, un indicateur clé d'une écologie de peau en bonne santé, soulignant la relation symbiotique entre l'intégrité de la barrière et la composition microbienne. Ces résultats soulignent l'importance des structures émollientes multilamellaires dans les traitements dermatologiques, avec des implications potentielles pour la conception d'interventions cutanées avancées qui soutiennent de manière holistique la résilience cutanée et l'homéostasie.
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Microbiota , Crema para la Piel , Fenómenos Fisiológicos de la Piel , Humanos , Método Doble Ciego , Adulto , Microbiota/efectos de los fármacos , Persona de Mediana Edad , Femenino , Adulto Joven , Fenómenos Fisiológicos de la Piel/efectos de los fármacos , Masculino , Epidermis/efectos de los fármacos , Epidermis/microbiología , Piel/microbiología , Piel/efectos de los fármacosRESUMEN
Pandoraea spp. are gram-negative, nonfermenting rods mainly known to infect patients with cystic fibrosis (CF). Outbreaks have been reported from several CF centers. We report a Pandoraea spp. outbreak comprising 24 non-CF patients at a large university hospital and a neighboring heart center in Germany during July 2019-December 2021. Common features in the patients were critical illness, invasive ventilation, antimicrobial pretreatment, and preceding surgery. Complicated and relapsing clinical courses were observed in cases with intraabdominal infections but not those with lower respiratory tract infections. Genomic analysis of 15 isolates identified Pandoraea commovens as the genetically most similar species and confirmed the clonality of the outbreak strain, designated P. commovens strain LB-19-202-79. The strain exhibited resistance to most antimicrobial drugs except ampicillin/sulbactam, imipenem, and trimethoprim/sulfamethoxazole. Our findings suggest Pandoraea spp. can spread among non-CF patients and underscore that clinicians and microbiologists should be vigilant in detecting and assessing unusual pathogens.
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Antiinfecciosos , Burkholderiaceae , Fibrosis Quística , Humanos , Fibrosis Quística/complicaciones , Fibrosis Quística/epidemiología , Bacterias Gramnegativas , Combinación Trimetoprim y Sulfametoxazol , Burkholderiaceae/genética , Alemania/epidemiologíaRESUMEN
INTRODUCTION: Skin microbiome and skin physiology are important indicators of the epidermal homeostasis status. Stress models can reveal pathological conditions and modulating effects. Here we investigated the cutaneous microbiome in relation to skin physiology after mild tape stripping (TS) without treatment compared to two cosmetic leave-on lotions (pH 5.5 vs. pH 9.3) in 25 healthy volunteers. METHODS: The microbiome was analyzed by 16S-rRNA-gene amplicon sequencing and put in relation to the following skin physiology parameter: epidermal barrier function (TEWA-Meter TM300), stratum corneum hydration (Corneometer CM 825), surface pH (pH-Meter), and skin erythema (Mexameter). RESULTS: TS reduced the alpha diversity with a recovery over 7 days without treatment. Both lotions significantly accelerated the recovery of the alpha diversity already after 2 days with a slightly higher rate for the acidic lotion. After TS, the relative abundance of Proteobacteria was increased, whereas Actinobacteria were reduced. The relative abundances of typical skin-associated genera were reduced after TS. Taxa compositions returned to normal levels after 7 days in all treatment groups. An accelerated normalization could be observed with both lotions already after 2 days. A significant difference in skin pH was observed on day 2 and day 7 with an increased pH for the alkaline lotion. Both lotions induced an increase in stratum corneum hydration. CONCLUSION: The study proved the suitability of an experimental stress model in the assessment of skin surface microbiome in relation to skin physiology. Stratum corneum hydration increased significantly with both lotions already at day 2. Microbiome parameters (alpha diversity, mean relative taxa, abundance of selected genera) normalized over 2-7 days. The following mechanisms could be responsible for the accelerated normalization of the microbiome: (a) optimized hydration during the recovery phase, (b) the composition of the lotion, (c) the induced repair mechanism. Thus, the formulation has a positive effect on the stratum corneum hydration and subsequently on cutaneous microbiome and skin physiology. Furthermore, this eventually has implications on the modulation of exogenous stress-induced epidermal alterations.
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Epidermis , Microbiota , Emolientes , Emulsiones/farmacología , Humanos , Piel , Cuidados de la Piel , Fenómenos Fisiológicos de la PielRESUMEN
OBJECTIVES: To investigate sonication as a new tool in microbiological probing of dental infections. METHODS: Comparison of a standard probing method: intraoperative swab, with sonication, and vortex of the removed tooth, was performed on 20 carious destructed teeth. Illumina high throughput sequencing of the 16S-rRNA-gene was used for assessing the microbial composition. Antibiotic susceptibility has been assigned based on known resistances of each detected species. Probing procedures were compared using Bland-Altmann-Test, and antibiotic susceptibility using the Friedmann-Test and alpha-adjusted post-hoc-analysis. RESULTS: In total, 60 samples were analysed: 20 intraoperative swabs, 20 vortex fluids, and 20 sonication fluids. Sonication fluid yielded the highest number of bacterial sequencing reads in all three procedures. Comparing the operational taxonomic units (OTUs) of the identified bacteria, significantly more OTUs were found in sonication fluid samples. Phylum and order abundances varied between the three procedures. Significantly more Actinomycetales have been found in sonication fluid samples compared to swab samples. The assigned resistance rates for the identified bacteria (1.79-31.23%) showed no differences between the tested probing procedures. The lowest resistance rates were found for amoxicillin + clavulanate (3.95%) and levofloxacin (3.40%), with the highest in amoxicillin (30.21%) and clindamycin (21.88%). CONCLUSIONS: By using sonication on extracted teeth, it is possible to get a more comprehensive image of the residing microbial flora compared to the standard procedure. If sonication is not available, vortexing is a potential alternative. In immunocompromised patients, especially when actinomycosis is suspected, sonication should be considered for a more detailed microbiological evaluation of the potential disease-causing microbiome. Due to the high rates of antibiotic resistance, a more targeted antibiotic therapy is favourable. Levofloxacin should be considered as a first-line alternative to amoxicillin + clavulanate in patients with an allergy to penicillin.
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Caries Dental , Microbiota , Amoxicilina , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacterias , Ácido Clavulánico , Humanos , Levofloxacino , Proyectos Piloto , Estudios Prospectivos , SonicaciónRESUMEN
BACKGROUND: Living conditions in homeless shelters facilitate the transmission of COVID-19. Social determinants and pre-existing health conditions place homeless people at increased risk of severe disease. Described outbreaks in homeless shelters resulted in high proportions of infected residents and staff members. In addition to other infection prevention strategies, regular shelter-wide (universal) testing for COVID-19 may be valuable, depending on the level of community transmission and when resources permit. METHODS: This was a prospective feasibility cohort study to evaluate universal testing for COVID-19 at a homeless shelter with 106 beds in Berlin, Germany. Co-researchers were recruited from the shelter staff. A PCR analysis of saliva or self-collected nasal/oral swab was performed weekly over a period of 3 weeks in July 2020. Acceptability and implementation barriers were analyzed by process evaluation using mixed methods including evaluation sheets, focus group discussion and a structured questionnaire. RESULTS: Ninety-three out of 124 (75%) residents were approached to participate in the study. Fifty-one out of the 93 residents (54.8%) gave written informed consent; thus 41.1% (51 out of 124) of all residents were included in the study. Among these, high retention rates (88.9-93.6%) of a weekly respiratory specimen were reached, but repeated collection attempts, as well as assistance were required. Around 48 person-hours were necessary for the sample collection including the preparation of materials. A self-collected nasal/oral swab was considered easier and more hygienic to collect than a saliva specimen. No resident was tested positive by RT-PCR. Language barriers were the main reason for non-participation. Flexibility of sample collection schedules, the use of video and audio materials, and concise written information were the main recommendations of the co-researchers for future implementation. CONCLUSIONS: Voluntary universal testing for COVID-19 is feasible in homeless shelters. Universal testing of high-risk facilities will require flexible approaches, considering the level of the community transmission, the available resources, and the local recommendations. Lack of human resources and laboratory capacity may be a major barrier for implementation of universal testing, requiring adapted approaches compared to standard individual testing. Assisted self-collection of specimens and barrier free communication may facilitate implementation in homeless shelters. Program planning must consider homeless people's needs and life situation, and guarantee confidentiality and autonomy.
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COVID-19 , Personas con Mala Vivienda , Prueba de COVID-19 , Estudios de Cohortes , Estudios de Factibilidad , Alemania , Humanos , Estudios Prospectivos , SARS-CoV-2RESUMEN
BACKGROUND: Evolving SARS-CoV-2 variants and changing levels of pre-existing immunity require re-evaluation of antigen-detecting rapid diagnostic test (Ag-RDT) performance. We investigated possible associations between Ag-RDT sensitivity and various potential influencing factors, such as immunisation status and viral variant, in symptomatic hospital employees. METHODS: In this observational study, RT-PCR, Ag-RDT, and symptom-specific data were collected at three SARS-CoV-2 test centres for employees of the Charité-Universitätsmedizin Berlin hospital (Berlin, Germany). Employees reporting SARS-CoV-2-like symptoms, those at an increased risk of infection (eg, due to contact with an infected person), those testing positive in a previous self-administered Ag-RDT, or those seeking release-testing to return to work at least 7 days after a positive RT-PCR test were eligible for combined testing by RT-PCR and Ag-RDT. Only data from individuals with an ongoing SARS-CoV-2 infection as assessed by RT-PCR were used for further analysis. Bayesian regression analyses were done to evaluate possible differences in viral load and Ag-RDT sensitivity according to viral variant and immunisation status (previous vaccination or recovery from infection), using data from first RT-PCR positive samples in an infection. A comprehensive logistic regression analysis was used to investigate potential concomitant associations between Ag-RDT sensitivity and level of pre-existing immunity, time post symptom onset, viral load, gender, age, and Ag-RDT device. Ag-RDT performance was also compared between supernatants from cell cultures infected with the omicron variant of concern (VOC) or the wild-type strain (pre-VOC). FINDINGS: Between Nov 30, 2020 and Feb 11, 2022, a total of 14 773 samples from 7675 employees were tested for SARS-CoV-2 by both RT-PCR and Ag-RDT. We found a negative association between immunisation status and Ag-RDT sensitivity in symptomatic employees, with an observed sensitivity of 82% (94% highest posterior density interval [HPDI] 78-86) in immunologically naive participants compared with 73% (68-78) in multiply immunised individuals (ie, those with at least two vaccinations or recoveries from infection) and median log10 viral loads of 7·02 (IQR 5·83-8·07) and 8·08 (6·80-8·89), respectively. The dominant viral variant changed several times during the study period, from the pre-VOC period (sensitivity 80% [94% HPDI 75-85] in symptomatic participants) through the alpha variant (82% [70-94]), delta variant (75% [69-82]), and omicron variant (72% [65-79]) waves, concomitantly with a steep increase in vaccination coverage in our dataset. In a comparison of Ag-RDT performance on cell culture supernatants, we found no difference between the wild-type and omicron viral variants. INTERPRETATION: On the basis of our findings and data from other studies, we hypothesise that the observed reduction in clinical Ag-RDT sensitivity, despite higher SARS-CoV-2 RNA loads, is due to shorter incubation times later in our study period resulting from increased population immunity or changes in immune response dynamics caused by later SARS-CoV-2 VOCs. FUNDING: Berlin University Alliance, German Ministry of Education and Research, the EU (Projects EU4Health and ReCoVer), and the Berlin Institute of Health.
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COVID-19 , SARS-CoV-2 , Carga Viral , Humanos , COVID-19/inmunología , COVID-19/diagnóstico , COVID-19/virología , COVID-19/epidemiología , Masculino , Femenino , Persona de Mediana Edad , SARS-CoV-2/inmunología , Adulto , Sensibilidad y Especificidad , Prueba Serológica para COVID-19/métodos , Berlin/epidemiología , Alemania/epidemiología , Antígenos Virales/inmunologíaRESUMEN
Several studies have documented the significant impact of methodological choices in microbiome analyses. The myriad of methodological options available complicate the replication of results and generally limit the comparability of findings between independent studies that use differing techniques and measurement pipelines. Here we describe the Mosaic Standards Challenge (MSC), an international interlaboratory study designed to assess the impact of methodological variables on the results. The MSC did not prescribe methods but rather asked participating labs to analyze 7 shared reference samples (5 × human stool samples and 2 × mock communities) using their standard laboratory methods. To capture the array of methodological variables, each participating lab completed a metadata reporting sheet that included 100 different questions regarding the details of their protocol. The goal of this study was to survey the methodological landscape for microbiome metagenomic sequencing (MGS) analyses and the impact of methodological decisions on metagenomic sequencing results. A total of 44 labs participated in the MSC by submitting results (16S or WGS) along with accompanying metadata; thirty 16S rRNA gene amplicon datasets and 14 WGS datasets were collected. The inclusion of two types of reference materials (human stool and mock communities) enabled analysis of both MGS measurement variability between different protocols using the biologically-relevant stool samples, and MGS bias with respect to ground truth values using the DNA mixtures. Owing to the compositional nature of MGS measurements, analyses were conducted on the ratio of Firmicutes: Bacteroidetes allowing us to directly apply common statistical methods. The resulting analysis demonstrated that protocol choices have significant effects, including both bias of the MGS measurement associated with a particular methodological choices, as well as effects on measurement robustness as observed through the spread of results between labs making similar methodological choices. In the analysis of the DNA mock communities, MGS measurement bias was observed even when there was general consensus among the participating laboratories. This study was the result of a collaborative effort that included academic, commercial, and government labs. In addition to highlighting the impact of different methodological decisions on MGS result comparability, this work also provides insights for consideration in future microbiome measurement study design.
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Heces , Metagenómica , Microbiota , ARN Ribosómico 16S , Humanos , Metagenómica/métodos , Metagenómica/normas , ARN Ribosómico 16S/genética , Heces/microbiología , Microbiota/genética , Sesgo , Metagenoma , Microbioma Gastrointestinal/genética , Análisis de Secuencia de ADN/métodos , Bacterias/genética , Bacterias/clasificación , Bacterias/aislamiento & purificación , Secuenciación de Nucleótidos de Alto Rendimiento/métodosRESUMEN
Crohn's disease (CD) is associated with changes in the microbiome. The role of these changes and their precise association with disease course and activity remain ambiguous. In this prospective single-center study, the mucosal microbiome of surgical CD and non-CD patients was compared at the time of surgery. Microbial analyses were individually performed for ileal and colonic tissue samples obtained during surgery using 16S-rRNA-gene amplicon sequencing. Three groups out of the 46 included patients were formed: 1) a study group of CD of patients who received ileocecal resection due to CD involvement (CD study, n=10); 2) a control group of non-CD of patients who received intestinal resection due to indications other than CD (non-CD control, n=27); and 3) a second control group of CD who underwent resection of the intestine not affected by CD (CD non-affected control, n=9). Species richness and Shannon diversity were not different between all formed groups and regions analyzed (p>0.05). Several significant taxonomic differences were seen at the phylum-, order-, and genus-levels between the formed groups, such as a decrease of Firmicutes (phylum-level) and an increase of Bacteroides and Escherichia/Shigella/Pseudescherichia (genus-level) in CD study - colon vs. the non-CD control - colon (p ≤ 0.05). The CD non-affected control presented the largest amount of differentially abundant taxa in comparison to the other groups. These results underline that CD is accompanied by changes in affected and non-affected intestinal regions compared to non-CD controls. This study contributes the mucosal microbiome of a well-defined subset of surgical CD patients without confounding aspects of the fecal microbiome or regional microbial differences to the existing literature.
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Enfermedad de Crohn , Microbioma Gastrointestinal , Microbiota , Humanos , Enfermedad de Crohn/cirugía , Estudios Prospectivos , Mucosa IntestinalRESUMEN
BACKGROUND: The control of translation initiation is a crucial component in the regulation of gene expression. The eukaryotic initiation factor 2α (eIF2α) mediates binding of the initiator transfer-messenger-RNA to the AUG initiation codon, and thus controls a rate-limiting step in translation initiation. Phosphorylation of eIF2α at serine 51 is linked to cellular stress response and attenuates translation initiation. The biochemistry of translation inhibition mediated by eIF2α phosphorylation is well characterized, yet the physiological importance in hematopoiesis remains only partially known. DESIGN AND METHODS: Using hematopoietic stem cells carrying a non-phosphorylatable mutant form of eIF2α (eIF2αAA), we examined the efficiency of reconstitution in wild-type and B-cell-deficient microMT C57BL/6 recipients in two independent models. RESULTS: We provide evidence that phosphorylation-deficient eIF2α mutant hematopoietic stem cells may repopulate lethally irradiated mice but have a defect in the development and maintenance of newly formed B cells in the bone marrow and of naïve follicular B cells in the periphery. The mature B-cell compartment is markedly reduced in bone marrow, spleen and peripheral blood, and B-cell receptor-mediated proliferation in vitro and serum immunoglobulin secretion in vivo are impaired. CONCLUSIONS: The data suggest that regulation of translation through eIF2α phosphorylation is dispensable in hematopoietic reconstitution but essential during late B-cell development.
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Linfocitos B/inmunología , Factor 2 Eucariótico de Iniciación/metabolismo , Animales , Formación de Anticuerpos/genética , Linfocitos B/citología , Linfocitos B/metabolismo , Diferenciación Celular , Quimera , Factor 2 Eucariótico de Iniciación/genética , Regulación del Desarrollo de la Expresión Génica , Genotipo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mutación/genética , Fosforilación , Células Madre/metabolismo , Transducción GenéticaRESUMEN
Despite their distinct clinical manifestation, frontal fibrosing alopecia (FFA) and lichen planopilaris (LPP) display similar histopathologic features. Aberrant innate immune responses to endogenous or exogenous triggers have been discussed as factors that could drive inflammatory cascades and the collapse of the stem cell niche. In this exploratory study, we investigate the bacterial composition of scalp skin and plucked hair follicles (HF) of patients with FFA, LPP and alopecia areata circumscripta (AAc), as well as healthy individuals, in relation to cellular infiltrates and the expression of defense mediators. The most abundant genus in lesional and non-lesional HFs of LPP and FFA patients was Staphylococcus, while Lawsonella dominated in healthy individuals and in AAc patients. We observed statistically significant differences in the ratio of Firmicutes to Actinobacteria between healthy scalp, lesional, and non-lesional sites of FFA and LPP patients. This marked dysbiosis in FFA and LPP in compartments close to the bulge was associated with increased HßD1 and HßD2 expression along the HFs from lesional sites, while IL-17A was increased in lesional HF from AAc patients. The data encourage further studies on how exogenous factors and molecular interactions across the HF epithelium could contribute to disease onset and propagation.
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BACKGROUND: A total of 62/66 (93.9%) residents in a senior citizen home in Bremen, Germany, received the first dose of the Biontech/Pfizer vaccine BNT162b2 on December 27th 2020. After routine severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen tests showed positive results on January 5th, all residents and staff were tested by RT-PCR. RESULTS: Nine staff members and 23 residents had a positive result. PCR positive staff members reported mild to severe COVID-19 symptoms, one was hospitalized. None of them had been vaccinated. In contrast, the vaccinated residents reported no or only mild symptoms. Sequencing of the SARS-CoV-2 genomes of infected individuals revealed a monophyletic origin of the outbreak within the PANGO lineage B.1.177.86. CONCLUSIONS: In summary, our data show that partial vaccination prevented severe COVID-19 among the residents during this local SARS-CoV-2 outbreak, suggesting a high effectiveness of even a single vaccine dose, but also emphasize that asymptomatic individuals might still be carriers/spreaders.
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COVID-19 , Vacunas , Anciano , Vacuna BNT162 , Vacunas contra la COVID-19 , Brotes de Enfermedades , Alemania , Humanos , SARS-CoV-2RESUMEN
BACKGROUND: The upper follicular compartment, a well-known reservoir of cutaneous microbiota, constitutes a space for intensive cross-barrier dialogue. The lower follicle comprises the bulb and bulge, structures with relative immune-privileged status, crucial for physiological cycling, and widely considered to be microbial-free. OBJECTIVES: Following our initial immunohistochemical screening for regulatory cytokines and defensin expression in anagen hair follicles, we aimed to confirm our results with a follow-up ELISA investigation. We postulated that exposure to microbial components may trigger expression, and thus opted to investigate microbial presence in this area. MATERIALS & METHODS: We performed immunohistochemical staining for selected cytokines and antimicrobial peptides, and Gram and Giemsa staining on tissue sections from healthy individuals. Based on ELISA analyses, we confirmed a marked presence of IL-17A- and HBD2 in infrainfundibular compartments from plucked anagen hair follicles of 12 individuals (six females, six males; frontal and occipital scalp sites). 16S rRNA sequencing on microbial DNA extracted from lower follicles, as well as fluorescence in situ hybridization (FISH) were applied to explore bacterial presence in the infrainfundibular compartments. RESULTS: 16S rRNA sequencing yielded reproducible data of bacterial presence in infrainfundibular compartments of plucked scalp follicles; Lawsonella clevelandensis, Staphylococcaceae and Propionibacteriaceae were the most abundant bacteria. Also, FISH revealed biofilm structures formed by Cutibacterium acnes (formerly Propionibacterium acnes) and Staphylococcus sp. below the infundibulum. CONCLUSION: As the skin microbiome largely influences the local immune system, the presence of bacteria in proximity to follicular immune-privileged areas may be of relevance to hair cycling in health and disease.
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ADN Bacteriano/análisis , Folículo Piloso/química , Proteínas Citotóxicas Formadoras de Poros/análisis , Adulto , Femenino , Humanos , Masculino , Cuero Cabelludo , Adulto JovenRESUMEN
Two elementary parameters for quantifying viral infection and shedding are viral load and whether samples yield a replicating virus isolate in cell culture. We examined 25,381 cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Germany, including 6110 from test centers attended by presymptomatic, asymptomatic, and mildly symptomatic (PAMS) subjects, 9519 who were hospitalized, and 1533 B.1.1.7 lineage infections. The viral load of the youngest subjects was lower than that of the older subjects by 0.5 (or fewer) log10 units, and they displayed an estimated ~78% of the peak cell culture replication probability; in part this was due to smaller swab sizes and unlikely to be clinically relevant. Viral loads above 109 copies per swab were found in 8% of subjects, one-third of whom were PAMS, with a mean age of 37.6 years. We estimate 4.3 days from onset of shedding to peak viral load (108.1 RNA copies per swab) and peak cell culture isolation probability (0.75). B.1.1.7 subjects had mean log10 viral load 1.05 higher than that of non-B.1.1.7 subjects, and the estimated cell culture replication probability of B.1.1.7 subjects was higher by a factor of 2.6.
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Infecciones Asintomáticas , COVID-19/transmisión , COVID-19/virología , SARS-CoV-2/fisiología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , COVID-19/diagnóstico , Prueba de Ácido Nucleico para COVID-19 , Células CACO-2 , Niño , Preescolar , Femenino , Alemania , Hospitalización , Humanos , Lactante , Masculino , Persona de Mediana Edad , Probabilidad , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/patogenicidad , Carga Viral , Replicación Viral , Esparcimiento de Virus , Adulto JovenRESUMEN
We report the draft genome sequence of Mycobacteroides sp. strain LB1, isolated from the sputum of a cystic fibrosis patient in Berlin, Germany. The genome size is 4.9 Mbp with a GC content of 63.8%. The genome is only distantly related to other Mycobacteroides species, suggesting that it may represent a novel species.
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Aberrant Notch activation is linked to cancer since 1991 when mammalian Notch1 was first identified as part of the translocation t(7;9) in a subset of human T-cell acute lymphoblastic leukemias (T-ALL). Since then oncogenic Notch signaling has been found in many solid and hematopoietic neoplasms. Depending on tumor type Notch interferes with differentiation, proliferation, survival, cell-cycle progression, angiogenesis, and possibly self-renewal. In hematopoietic neoplasms, recent findings indicate an important role of Notch for T-ALL induction and progression and the pathogenesis of human T- and B-cell-derived lymphomas. Notch signaling has been identified as a potential new therapeutic target in these hematopoietic neoplasms. This review will focus on the most recent findings on Notch signaling in leukemias and lymphomas and its potential role in the maintenance of malignant stem cells.
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Leucemia/metabolismo , Linfoma/metabolismo , Receptores Notch/metabolismo , Transducción de Señal/fisiología , Humanos , Receptores Notch/genéticaRESUMEN
We have identified TRB3, a human homologue of Drosophila tribbles, as a novel transcriptional target of phosphatidylinositol (PI) 3-kinase. TRB3 expression is remarkably reduced in prostate cancer PC-3 cells after inhibition of PI 3-kinase. TRB3 expression is furthermore controlled by nutrient supplies: Both the lack of glucose or amino acids results in a substantial increase in TRB3 protein levels in a PI 3-kinase-dependent manner. This increase is reversed by the addition of fresh nutrients. Stress stimuli, such as osmotic stress, hypoxia or serum starvation do not affect TRB3 expression. Thus, TRB3 may function as a nutrient sensor. Inhibition of TRB3 expression has no effect on growth of PC-3 cells under regular growth conditions. However, in the absence of glucose overexpression of TRB3 in PC-3 cells can interfere with apoptosis and restore growth on extracellular matrix. Taken together, our data point to an important role of TRB3 in sensing reduced nutrient supplies and in providing survival signals during these periods.
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Aminoácidos Esenciales/deficiencia , Proteínas de Ciclo Celular/metabolismo , Glucosa/deficiencia , Fosfatidilinositol 3-Quinasas/metabolismo , Neoplasias de la Próstata/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Represoras/metabolismo , Aminoácidos Esenciales/farmacología , Proteínas de Ciclo Celular/efectos de los fármacos , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Medios de Cultivo Condicionados/química , Medios de Cultivo Condicionados/farmacología , Glucosa/farmacología , Células HeLa , Humanos , Masculino , Fosfatidilinositol 3-Quinasas/farmacología , Neoplasias de la Próstata/patología , Proteínas Serina-Treonina Quinasas/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/genética , ARN Mensajero/biosíntesis , Proteínas Represoras/efectos de los fármacos , Proteínas Represoras/genética , Transducción de Señal , Activación TranscripcionalRESUMEN
Cancer cells frequently evade apoptosis during tumorigenesis by acquiring mutations in apoptotic regulators. Chronic activation of the PI 3-kinase-Akt pathway through loss of the tumor suppressor PTEN is one mechanism by which these cells can gain increased protection against apoptosis. We report here that REDD1 (RTP801) can act as a transcriptional downstream target of PI 3-kinase signaling in human prostate cancer cells (PC-3). REDD1 expression is markedly reduced in PC-3 cells treated with LY294002 (LY) or Rapamycin and strongly induced under hypoxic conditions in a hypoxia-inducible factor-1 (HIF-1)-dependent manner. Loss of function studies employing antisense molecules or RNA interference indicate that REDD1 is essential for invasive growth of prostate cancer cells in vitro and in vivo. Reduced REDD1 levels can sensitize cells towards apoptosis, whereas elevated levels of REDD1 induced by hypoxia or overexpression desensitize cells to apoptotic stimuli. Taken together our data designate REDD1 as a novel target for therapeutic intervention in prostate cancer.
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Fosfatidilinositol 3-Quinasas/fisiología , Neoplasias de la Próstata/metabolismo , Factores de Transcripción/fisiología , Apoptosis , Hipoxia de la Célula , Línea Celular Tumoral , Cromonas/farmacología , Cobalto/farmacología , Dimetilsulfóxido/farmacología , Expresión Génica/genética , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia , Masculino , Morfolinas/farmacología , Invasividad Neoplásica/genética , Fosfatidilinositol 3-Quinasas/genética , Inhibidores de las Quinasa Fosfoinosítidos-3 , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/inmunología , ARN sin Sentido/genética , Transducción de Señal , Sirolimus/farmacología , Factores de Transcripción/análisis , Factores de Transcripción/genética , Regulación hacia ArribaRESUMEN
A better understanding of events triggering chronic myeloid leukemia progression is critical for optimized clinical management of chronic myeloid leukemia (CML). We sought to validate that increased expression of Musashi 2 (MSI2), a post-transcription regulator, is associated with progression and prognosis. Screening of 152 patients with CML showed that MSI2 was significantly decreased among patients with CML in chronic phase (CP) at diagnosis (p < 0.0001), but found no significant difference between the normal control group and treated patients with CML in CP. Moreover MSI2 was significantly increased (p < 0.0001) in patients with advance disease (AD) CML. Furthermore, our human hematopoietic cell line data imply that MSI2 and BCR-ABL1 mRNA expression are correlated. However, these data cast a doubt on earlier reports that MSI2 effects HES1 expression via NUMB-NOTCH signaling.
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Regulación Leucémica de la Expresión Génica , Células Madre Hematopoyéticas/metabolismo , Leucemia Mieloide de Fase Crónica/metabolismo , Leucemia Mieloide de Fase Crónica/patología , Proteínas de Unión al ARN/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Proteínas de Fusión bcr-abl/genética , Células Madre Hematopoyéticas/patología , Humanos , Técnicas para Inmunoenzimas , Leucemia Mieloide de Fase Crónica/genética , Leucemia Mieloide de Fase Crónica/mortalidad , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Tasa de Supervivencia , Regulación hacia Arriba , Adulto JovenRESUMEN
Multiple myeloma (MM) is a lethal human cancer characterized by a clonal expansion of malignant plasma cells in bone marrow. Mouse models of human MM are technically challenging and do not always recapitulate human disease. Therefore, new mouse models for MM are needed. Mineral-oil induced plasmacytomas (MOPC) develop in the peritoneal cavity of oil-injected BALB/c mice. However, MOPC typically grow extramedullary and are considered poor models of human MM. Here we describe an in vivo-selected MOPC315 variant, called MOPC315.BM, which can be maintained in vitro. When injected i.v. into BALB/c mice, MOPC315.BM cells exhibit tropism for bone marrow. As few as 10(4) MOPC315.BM cells injected i.v. induced paraplegia, a sign of spinal cord compression, in all mice within 3-4 weeks. MOPC315.BM cells were stably transfected with either firefly luciferase (MOPC315.BM.Luc) or DsRed (MOPC315.BM.DsRed) for studies using noninvasive imaging. MOPC315.BM.Luc cells were detected in the tibiofemoral region already 1 hour after i.v. injection. Bone foci developed progressively, and as of day 5, MM cells were detected in multiple sites in the axial skeleton. Additionally, the spleen (a hematopoietic organ in the mouse) was invariably affected. Luminescent signals correlated with serum myeloma protein concentration, allowing for easy tracking of tumor load with noninvasive imaging. Affected mice developed osteolytic lesions. The MOPC315.BM model employs a common strain of immunocompetent mice (BALB/c) and replicates many characteristics of human MM. The model should be suitable for studies of bone marrow tropism, development of osteolytic lesions, drug testing, and immunotherapy in MM.
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Médula Ósea/patología , Modelos Animales de Enfermedad , Ratones , Mieloma Múltiple/patología , Osteólisis/patología , Animales , Línea Celular Tumoral , Expresión Génica , Genes Reporteros , Mediciones Luminiscentes , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Imagen Molecular , Mieloma Múltiple/inducido químicamente , Mieloma Múltiple/mortalidad , Osteólisis/diagnóstico por imagen , Radiografía , TransfecciónRESUMEN
Mitochondria are dynamic organelles that change morphology by controlled fission and fusion events. Mitochondrial fission is regulated by a conserved protein complex assembled at the outer membrane. Human MTP18 is a novel nuclear-encoded mitochondrial membrane protein, implicated in controlling mitochondrial fission. Upon overexpression of MTP18, mitochondrial morphology was altered from filamentous to punctate structures suggesting excessive mitochondrial fission. Mitochondrial fragmentation was blocked in cells coexpressing either the mitochondrial fusion protein Mfn1 or Drp1(K38A), a dominant negative version of the fission protein Drp1. Also, a loss-of function of endogenous MTP18 by RNA interference (RNAi) resulted in highly fused mitochondria. Moreover, MTP18 appears to be required for mitochondrial fission because it is blocked after overexpression of hFis1 in cells with RNAi-mediated MTP18 knockdown. In conclusion, we propose that MTP18 functions as an essential intramitochondrial component of the mitochondrial division apparatus, contributing to the maintenance of mitochondrial morphology.