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1.
Artículo en Inglés | MEDLINE | ID: mdl-38607512

RESUMEN

The well preserved skeleton of Joseph Huber, a very well-known historical character of the 19th century Munich, also nicknamed "Finessen-Sepperl", is the starting point of the reconstruction of life and death of this historical individual. He was known as a postilion d´amour (love's messenger) of the Royal Bavarian capital with numerous comments and anecdotes and a few biographical sketches that indicate he remained well until the last few years of his life where requests for his duties lessened. The skeleton shows a small-sized male individual with almost complete loss of teeth, but otherwise very well-mineralized bone, having suffered from three episodes of trauma - an old-healed incomplete femoral neck fracture leading to severe osteoarthrosis, a clavicle fracture of the medial third with a few weeks old callus formation, and fresh serial rib fractures along with severe skull trauma with fractures of the os temporale and petrosum, presumably leading to intracranial bleeding and finally death. The type and distribution of these latter two injuries are in agreement with a murderous attack - which was retrospectively reported several years after his death, while the old-healed femoral neck fracture may have caused reduction in Joseph´s walking activities but not reduced requests for his services. Paleopathology not only identifies the terminal decline, but also previous diseases of this Old Bavarian character and thereby completes his story.

2.
Colorectal Dis ; 25(5): 943-953, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36748436

RESUMEN

AIM: Appendiceal neoplasms are rare subtypes of colorectal tumours that mainly affect younger patients some 20 years earlier than other colon tumours. The aim of this study was to gain more insight into the histological subtypes of this rare disease and include cases previously excluded, such as mucinous neoplasia. METHOD: The cohort study included 1097 patients from the Munich Cancer Registry (MCR) diagnosed between 1998 and 2020. Joinpoint analysis was used to determine trend in incidence. Baseline demographic comparisons and survival analyses using competing risk and univariate/multivariate methods were conducted according to tumour histology: adenocarcinoma (ADENO), neuroendocrine neoplasia (NEN), mixed adeno-neuroendocrine carcinoma (MANEC), and low- (LAMN) and high-grade mucinous neoplasia (HAMN). RESULTS: Up to 2016 the number of cases increased significantly [annual per cent change (APC) = 6.86, p < 0.001] followed by a decline in the following years (APC = -14.82, p = 0.014; average APC = 2.5, p = 0.046). Comparison of all patients showed that NEN (48.4%) and mucinous neoplasms (11.6%) had a considerably better prognosis than ADENO (36.0%) and MANEC (3.0%, p < 0.0001). A multivariate analysis within the NEN and ADENO subgroups revealed that further histological classification was not prognostically relevant, while older age and regional tumour spread at diagnosis were associated with a poor prognosis. ADENO histology with high tumour grade and appendectomy only was also associated with poorer survival. CONCLUSION: Appendiceal neoplasms are histologically heterogeneous; however, this diversity becomes less relevant compared with the marked difference from cancers of the remaining colon. The previously observed increase in cases appears to be abating; fewer cases of appendicitis and/or appendectomies or changes in histopathological assessment may be behind this trend.


Asunto(s)
Adenocarcinoma , Neoplasias del Apéndice , Apéndice , Neoplasias del Colon , Tumores Neuroendocrinos , Humanos , Neoplasias del Apéndice/patología , Estudios de Cohortes , Estudios Retrospectivos , Neoplasias del Colon/epidemiología , Neoplasias del Colon/cirugía , Neoplasias del Colon/patología , Tumores Neuroendocrinos/epidemiología , Tumores Neuroendocrinos/cirugía , Tumores Neuroendocrinos/patología , Adenocarcinoma/epidemiología , Adenocarcinoma/patología , Pronóstico , Apendicectomía , Apéndice/patología
3.
Rheumatol Int ; 42(8): 1321-1330, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34605934

RESUMEN

Lung involvement in autoimmune diseases (AID) is uncommon, but may precede other organ manifestations. A diagnostic problem is chronicity presenting with lung fibrosis. A new category of interstitial pneumonia with autoimmune features for patients with clinical symptoms of AID and presenting with usual interstitial pneumonia (UIP) enables antifibrotic treatment for these patients. Hypersensitivity pneumonia (HP) and other forms of lung fibrosis were not included into this category. As these diseases based on adverse immune reactions often present with unspecific clinical symptoms, a specified pathological diagnosis will assist the clinical evaluation. We aimed to establish etiology-relevant differences of patterns associated with AID or HP combined with lung fibrosis. We retrospectively evaluated 51 cases of AID, and 29 cases of HP with lung fibrosis, and compared these to 24 cases of idiopathic pulmonary fibrosis (UIP/IPF). Subacute AID and HP most often presented with organizing pneumonia (OP), whereas chronicity was associated with UIP. Unspecified fibrosis was seen in a few cases, whereas NSIP pattern was rare. In 9 cases, the underlying etiology could not be defined. Statistically significant features differentiating chronic AID or HP from UIP/IPF are lymphocytic infiltrations into myofibroblastic/fibroblastic foci. Other features significantly associated with AID and HP were granulomas, isolated Langhans giant cells, and protein deposits, but seen in only a minority of cases. A combination of UIP with one of these features enabled a specific etiology-based diagnosis. Besides the antifibrotic drug regimen, additional therapies might be considered.


Asunto(s)
Alveolitis Alérgica Extrínseca , Enfermedades Autoinmunes , Fibrosis Pulmonar Idiopática , Alveolitis Alérgica Extrínseca/diagnóstico , Alveolitis Alérgica Extrínseca/etiología , Enfermedades Autoinmunes/complicaciones , Enfermedades Autoinmunes/diagnóstico , Diagnóstico Diferencial , Humanos , Fibrosis Pulmonar Idiopática/diagnóstico , Fibrosis Pulmonar Idiopática/patología , Pulmón/patología , Estudios Retrospectivos
4.
J Craniofac Surg ; 33(2): 372-374, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34690323

RESUMEN

ABSTRACT: We describe the peculiar facial morphology of a carved head dating to the end of the Roman Republican period (40 BCE) which displays evident unilateral asymmetry. A comprehensive discussion of the different etiologies is provided and a contextualization of this condition in the broader frame of Roman artistic verism is offered. This case study contributes to the knowledge of disease presentation in the ancient world, with a special focus on the anatomy of soft tissue pathology.


Asunto(s)
Cara , Asimetría Facial , Historia Antigua , Humanos
5.
J Infect Dis ; 223(11): 1973-1983, 2021 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-33045080

RESUMEN

Apoptosis is an indispensable mechanism for eliminating infected cells and activation of executioner caspases is considered to be a point of no return. Streptococcus pneumoniae, the most common bacterial pathogen causing community-acquired pneumonia, induces apoptosis via its pore-forming toxin pneumolysin, leading to rapid influxes of mitochondrial calcium [Ca2+]m as well as fragmentation, and loss of motility and membrane potential, which is accompanied by caspase-3/7 activation. Using machine-learning and quantitative live-cell microscopy, we identified a significant number of alveolar epithelial cells surviving such executioner caspase activation after pneumolysin attack. Precise single-cell analysis revealed the [Ca2+]m amplitude and efflux rate as decisive parameters for survival and death, which was verified by pharmacological inhibition of [Ca2+]m efflux shifting the surviving cells towards the dying fraction. Taken together, we identified the regulation of [Ca2+]m as critical for controlling the cellular fate under pneumolysin attack, which might be useful for therapeutic intervention during pneumococcal infection.


Asunto(s)
Proteínas Bacterianas , Calcio , Caspasas , Células Epiteliales/microbiología , Estreptolisinas , Apoptosis , Señalización del Calcio , Aprendizaje Automático , Mitocondrias , Streptococcus pneumoniae
6.
Genes Immun ; 22(7-8): 313-321, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34697411

RESUMEN

Interleukin-36α is a novel member of the IL-1 cytokine family that is highly expressed in epithelial tissues and several myeloid-derived cell types after induction. The transcription factor (TF) C/EBPß binds specifically to an essential half-CRE•C/EBP motif in the Il36a promoter to induce Il36a expression upon LPS stimulation. C/EBPs regulate gene expression by binding to recognition sequences that can contain 5'-cytosine-phosphate-guanine-3' dinucleotides (CpG), whose methylation can influence TF binding and gene expression. Herein we show that the half-CRE•C/EBP element in the Il36a promoter is differentially methylated in the murine RAW264.7 macrophage cell line and in primary murine macrophages. We demonstrate that C/EBPß binding to the half-CRE•C/EBP element in the Il36a promoter following LPS stimulation is insensitive to CpG methylation and that methylation of the CpG in the half-CRE•C/EBP element does not alter LPS-induced Il36a promoter activity which correlated with similar Il36a mRNA copy numbers and pro-IL-36α protein amount in both cell types. Taken together, our data indicate that C/EBPß binding to the half-CRE•C/EBP element and subsequent gene activation occurs independently of the CpG methylation status of the half-CRE•C/EBP motif and underlines the potential of C/EBPs to recognize methylated as well as unmethylated motifs.


Asunto(s)
Proteína beta Potenciadora de Unión a CCAAT , Macrófagos , Animales , Proteína beta Potenciadora de Unión a CCAAT/genética , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/genética , Macrófagos/metabolismo , Metilación , Ratones , Regiones Promotoras Genéticas , Activación Transcripcional
7.
Eur Spine J ; 30(1): 217-226, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32936402

RESUMEN

PURPOSE: The complement system is a crucial part of innate immunity. Recent work demonstrated an unexpected contribution to tissue homeostasis and degeneration. This study investigated for the first time, in human disc tissues, the deposition profile of the complement activation product terminal complement complex (TCC), an inflammatory trigger and inducer of cell lysis, and its inhibitor CD59, and their correlation with the degree of disc degeneration (DD). METHODS: Disc biopsies were collected from patients diagnosed with DD (n = 39, age 63 ± 12) and adolescent idiopathic scoliosis (AIS, n = 10, age 17 ± 4) and compared with discs from healthy Young (n = 11, age 7 ± 7) and Elder (n = 10, age 65 ± 15) donors. Immunohistochemical detection of TCC and CD59 in nucleus pulposus (NP), annulus fibrosus (AF) and endplate (EP) was correlated with age, Pfirrmann grade and Modic changes. RESULTS: Higher percentage of TCC+ cells was detected in the NP and EP of DD compared to Elder (P < 0.05), and in the EP of Young versus Elder (P < 0.001). In DD, TCC deposition was positively correlated with Pfirrmann grade, but not with Modic changes, whereas for Young donors, a negative correlation was found with age, indicating TCC's involvement not only in DD, but also in early stages of skeletal development. Higher CD59 positivity was found in AIS and DD groups compared to Young (P < 0.05), and it was negatively correlated with the age of the patients. CONCLUSION: TCC deposition positively correlated with the degree of disc degeneration. A functional relevance of TCC may exist in DD, representing a potential target for new therapeutics.


Asunto(s)
Anillo Fibroso , Degeneración del Disco Intervertebral , Disco Intervertebral , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Activación de Complemento , Complejo de Ataque a Membrana del Sistema Complemento , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Persona de Mediana Edad , Adulto Joven
8.
Postgrad Med J ; 97(1144): 75-76, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32404500

RESUMEN

What is the place of medico-historical cases in the professional practice of the disciplinary field of medicine and biology? How can these patients from the past be used for teaching and continuing medical education? How to justify their place in biomedical publications? In this article, we explain all the legitimacy of paleomedicine, and the need to intensify such research in the form of a well-individualised branch of paleopathology and the history of medicine.


Asunto(s)
Educación Médica/métodos , Paleopatología/educación , Humanos
9.
Pathologe ; 42(5): 530-539, 2021 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-34240239

RESUMEN

The comprehensive investigation of the excellently preserved mummy of Ötzi, the Iceman, and his equipment over the last 30 years has provided a wealth of information about the life and disease of this late Neolithic individual. This research has indicated that his origin was from a local southern Alpine population, that he grew up in the valleys of the Southern Alps, and that he had considerable local mobility. He had well-balanced nutrition with a mixed vegetable and animal diet. He was very mobile in the alpine terrain and of athletic constitution. The Iceman suffered from mild to moderate degenerative joint disease primarily of the right hip joint, slight spondylosis of the cervical and lumbar spine, a minor focal (premature) arteriosclerosis, lung anthracosis and possibly silicosis, previous pleuritic inflammation (possibly of post-specific origin), intestinal infections of the stomach by Helicobacter pylori and Trichuris trichiura worm infestation in the intestines, a mild osteomalacia of cancellous bone, and diverse pathologies of his teeth with dental caries and periodontitis, as well as hair anomalies. The presence of borreliosis is still under debate. As potential remedies, the Iceman carried some anthelmintic substances with him: a birch polypore and an anthelmintic fern. The numerous tattoos may also have had therapeutic effects. Finally, the last days of Ötzi could be reconstructed quite precisely: his gastrointestinal content indicates that the Iceman moved from Alpine heights to a lower location and then again up to the glacier region where he died. During this journey he encountered two attacks: the first, several days before his death, lead to a stabbing wound in his right hand; the second was an arrow hit that wounded the Iceman lethally at his left axilla by laceration of the subclavian artery.


Asunto(s)
Caries Dental , Momias , Animales , Cubierta de Hielo , Masculino , Estómago
10.
Arch Gynecol Obstet ; 300(2): 481-484, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30474713

RESUMEN

BACKGROUND: In breast tissue, pre-malignant lesions are classified as BIRADS 3. The treatment of this heterogeneous group varies with expertise and tools available. MATERIALS AND METHODS: With the example of two case reports, the literature is reviewed on current treatment options for BIRADS 3 breast lesions. RESULTS: About 7% of all B-type breast biopsies fall into the B3 category. Approximately 35% of these B3 lesions are due to FEA, 20% to PLs and another 20% to ADH. Due to improvement in diagnostics, the incidence is increasing, while their value as a predictive factor for malignancy has steadily been fallen. CONCLUSION: Depending on the histology of the needle biopsy, a complete resection with vacuum-assisted biopsy may be a treatment alternative to open biopsy.


Asunto(s)
Biopsia con Aguja/métodos , Neoplasias de la Mama/patología , Biopsia Guiada por Imagen/métodos , Mama/patología , Neoplasias de la Mama/clasificación , Detección Precoz del Cáncer , Femenino , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas
11.
PLoS Pathog ; 12(2): e1005408, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26829557

RESUMEN

Macrophages can be niches for bacterial pathogens or antibacterial effector cells depending on the pathogen and signals from the immune system. Here we show that type I and II IFNs are master regulators of gene expression during Legionella pneumophila infection, and activators of an alveolar macrophage-intrinsic immune response that restricts bacterial growth during pneumonia. Quantitative mass spectrometry revealed that both IFNs substantially modify Legionella-containing vacuoles, and comparative analyses reveal distinct subsets of transcriptionally and spatially IFN-regulated proteins. Immune-responsive gene (IRG)1 is induced by IFNs in mitochondria that closely associate with Legionella-containing vacuoles, and mediates production of itaconic acid. This metabolite is bactericidal against intravacuolar L. pneumophila as well as extracellular multidrug-resistant Gram-positive and -negative bacteria. Our study explores the overall role IFNs play in inducing substantial remodeling of bacterial vacuoles and in stimulating production of IRG1-derived itaconic acid which targets intravacuolar pathogens. IRG1 or its product itaconic acid might be therapeutically targetable to fight intracellular and drug-resistant bacteria.


Asunto(s)
Hidroliasas/inmunología , Interferones/inmunología , Legionella pneumophila/inmunología , Enfermedad de los Legionarios/inmunología , Macrófagos Alveolares/inmunología , Proteoma , Animales , Modelos Animales de Enfermedad , Femenino , Regulación de la Expresión Génica , Ontología de Genes , Hidroliasas/genética , Hidroliasas/metabolismo , Inmunidad Innata , Interferones/metabolismo , Legionella pneumophila/genética , Legionella pneumophila/metabolismo , Enfermedad de los Legionarios/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mitocondrias/metabolismo , Modelos Inmunológicos , Especies Reactivas de Oxígeno/metabolismo , Succinatos/metabolismo , Vacuolas/metabolismo , Vacuolas/microbiología
13.
Biochim Biophys Acta ; 1849(8): 966-78, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26066982

RESUMEN

Interleukin (IL)-36α - one of the novel members of the IL-1 family of cytokines - is a potent regulator of dendritic and T cells and plays an important role in inflammatory processes like experimental skin inflammation in mice and in mouse models for human psoriasis. Here, we demonstrate that C/EBPß, a transcription factor required for the selective expression of inflammatory genes, is a key activator of the Il36A gene in murine macrophages. RNAi-mediated suppression of C/EBPß expression in macrophages (C/EBPß(low) cells) significantly impaired Il36A gene induction following challenge with LPS. Despite the presence of five predicted C/EBP binding sites, luciferase reporter assays demonstrated that C/EBPß confers responsiveness to LPS primarily through a half-CRE•C/EBP element in the proximal Il36A promoter. Electrophoretic mobility shift assays showed that C/EBPß but not CREB proteins interact with this critical half-CRE•C/EBP element. In addition, overexpression of C/EBPß in C/EBPß(low) cells enhanced the expression of Il36A whereas CREB-1 had no effect. Finally, chromatin immunoprecipitation confirmed that C/EBPß but neither CREB-1, ATF-2 nor ATF4 is directly recruited to the proximal promoter region of the Il36A gene. Together, these findings demonstrate an essential role of C/EBPß in the regulation of the Il36A gene via the proximal half-CRE•C/EBP element in response to inflammatory stimuli.


Asunto(s)
Proteína beta Potenciadora de Unión a CCAAT/fisiología , Inflamación/genética , Interleucina-1/genética , Macrófagos/metabolismo , Animales , Secuencia de Bases , Sitios de Unión/genética , Células Cultivadas , Codón Iniciador/genética , Regulación de la Expresión Génica/efectos de los fármacos , Interleucina-1/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Psoriasis/genética , Elementos Reguladores de la Transcripción
17.
Biochem J ; 464(1): 3-11, 2014 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25181554

RESUMEN

NETs (neutrophil extracellular traps) have been described as a fundamental innate immune defence mechanism. During formation of NETs, the nuclear membrane is disrupted by an as-yet unknown mechanism. In the present study we investigated the role of human cathelicidin LL-37 in nuclear membrane disruption and formation of NETs. Immunofluorescence microscopy revealed that 5 µM LL-37 significantly facilitated NET formation by primary human blood-derived neutrophils alone, in the presence of the classical chemical NET inducer PMA or in the presence of Staphylococcus aureus. Parallel assays with a random LL-37 fragment library indicated that the NET induction is mediated by the hydrophobic character of the peptide. The trans-localization of LL-37 towards the nucleus and the disruption of the nuclear membrane were visualized using confocal fluorescence microscopy. In conclusion, the present study demonstrates a novel role for LL-37 in the formation of NETs.


Asunto(s)
Catelicidinas/farmacología , Trampas Extracelulares/fisiología , Neutrófilos/fisiología , Secuencia de Aminoácidos , Animales , Péptidos Catiónicos Antimicrobianos , Catelicidinas/genética , Trampas Extracelulares/efectos de los fármacos , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Neutrófilos/efectos de los fármacos , Neutrófilos/ultraestructura
18.
Mem Inst Oswaldo Cruz ; 110(1): 145-7, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25742276

RESUMEN

Trichuris trichiura is a soil-transmitted helminth which is prevalent in warm, moist, tropical and subtropical regions of the world with poor sanitation. Heavy whipworm can result either in Trichuris dysenteric syndrome - especially in children - or in a chronic colitis. In heavy infections, worms can spread proximally and may cause ileitis. Here we provide first microscopic evidence for a T. trichiura adult worm embedded in the rectum of a post-Colonial Brazilian adult mummy. During Colonial and post-Colonial times, many European chroniclers described a parasitic disease named Maculo whose symptomatology coincides with heavy helminthiasis. Based on our findings and on comparison of ancient textual evidence with modern description of heavy whipworm, we feel confident in considering that the two syndromes are expressions of the same pathological condition.


Asunto(s)
Parasitosis Intestinales/diagnóstico , Momias/parasitología , Tricuriasis/diagnóstico , Trichuris/aislamiento & purificación , Animales , Brasil , Historia del Siglo XVIII , Historia del Siglo XIX , Humanos , Recto/parasitología , Síndrome , Trichuris/ultraestructura
19.
Int J Med Microbiol ; 304(3-4): 370-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24444719

RESUMEN

Complete characterization of a Streptococcus pyogenes population from a defined geographic region comprises information on the plasmids that circulate in these bacteria. Therefore, we determined the distribution of small plasmids (<5kb) in a collection of 279 S. pyogenes isolates from India, where diversity of strains and incidence rates of S. pyogenes infections are high. The collection comprised 77 emm-types. For plasmid detection and discrimination, we developed PCRs for different plasmid replication initiation protein genes, the putative repressor gene copG and bacteriocin genes dysA and scnM57. Plasmid distribution was limited to 13 emm-types. Co-detection analysis using aforementioned PCRs revealed four distinct plasmid sub-types, two of which were previously unknown. Representative plasmids pA852 and pA996 of the two uncharacterized plasmid sub-types were sequenced. These two plasmids could be assigned to the pMV158 and the pC194/pUB110 family of rolling-circle plasmids, respectively. The majority of small plasmids found in India belonged to the two newly characterized sub-types, with pA852- and pA996-like plasmids amounting to 42% and 22% of all detected plasmids, respectively. None of the detected plasmids coded for a known antibiotic resistance gene. Instead, all of the four plasmid sub-types carried known or potential bacteriocin genes. These genes may have influence on the evolutionary success of certain S. pyogenes genotypes. Notably, pA852-like plasmids were found in all isolates of the most prevalent emm-type 11.0. Together, a priori fitness of this genotype and increased fitness due to the acquired plasmids may have rendered type emm11.0 successful and caused the prevalence of pA852-like plasmids in India.


Asunto(s)
Plásmidos/análisis , Plásmidos/clasificación , Infecciones Estreptocócicas/microbiología , Streptococcus pyogenes/genética , Bacteriocinas/genética , ADN Bacteriano/genética , Genes Bacterianos , Genotipo , Humanos , India , Reacción en Cadena de la Polimerasa , Streptococcus pyogenes/aislamiento & purificación
20.
Int J Med Microbiol ; 304(5-6): 685-95, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24856243

RESUMEN

Group A streptococcus (GAS, Streptococcus pyogenes) type emm1 is widely associated with streptococcal invasive disease. This type is prevalent worldwide but is rare in India. Instead, emm1-2 type which is closely related to emm1 but is a distinct type is more prevalent. Although emm1 has been well characterized, information available on emm1-2 is rare. In this study we present a comparative study of both types. DNA microarray analysis showed segregation of emm1 and emm1-2 isolates into two distinct clusters. Out of 229 arrayed genes, 83-87% were present, 6-9% absent and 4-8% genes were ambiguous in emm1 isolates. emm1-2 strains harboured only 68-77%, 11-13% were absent and 10-20% ambiguous genes. Fourteen genes, present in all emm1, were completely absent in the emm1-2 isolates. sfb1 is a gene which encodes for Streptococcal fibronectin binding adhesin and invasin which has restricted distribution among different emm types of GAS. A variant of sfb1 (sfb1-2) was the only gene which was present in all emm1-2 isolates, but absent from all emm1 strains. Sfb1 and Sfb1-2 differ in sequences in the aromatic domain and the proline rich repeat region, whereas the fibronectin binding region was conserved and exhibited similar fibronectin binding activity. The presence of Sfb1-2 in emm1-2 strains was concomitant with significantly higher fibronectin-binding and invasion efficiency of HEp-2 cells when compared to emm1 isolates. The role of Sfb1-2 in invasion was confirmed by latex bead assay. emm1-2 isolates follow membrane ruffling mechanism during invasion and intracellularly follow classical endocytic pathway. Further studies are required to understand the correlation between the presence of emm1-2 isolates and the disease pattern in North India.


Asunto(s)
Antígenos Bacterianos/genética , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Bacterianas/genética , Proteínas Portadoras/genética , Streptococcus pyogenes/crecimiento & desarrollo , Streptococcus pyogenes/genética , Factores de Virulencia/genética , Análisis por Conglomerados , Genotipo , Humanos , India , Análisis por Micromatrices , Análisis de Secuencia por Matrices de Oligonucleótidos , Virulencia
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