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1.
Ann Plast Surg ; 81(3): 290-294, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29916894

RESUMEN

BACKGROUND: Pseudogynecomastia is the increased aggregation of fatty tissue in the area of the male breast with resultant female appearance. Two forms can appear: pseudogynecomastia after massive weight loss (pseudogynecomastia obese [PO]) and pseudogynecomastia, which is caused only by adipose tissue (pseudogynecomastia fat). For PO, only the Gusenoff classification with corresponding operative treatment options exists. However, this classification is limited by the fact that it underestimates the extensive variability of residual fat tissue and skin excess, both crucial factors for operative planning. For this reason, we propose a modification of the treatment algorithm for the Gusenoff classification based on our results to achieve more masculine results. MATERIALS AND METHODS: A total of 43 male patients with PO were included in this retrospective study (grade 1a, n = 1; grade 1b, n = 1; grade 2, n = 17; grade 3, n = 24). Forty-two mastectomies with a free nipple-areola complex (NAC) transposition (grades 2 and 3) and 1 with a subcutaneous mastectomy (grade 1a) with periareolar lifting were performed. A retrospective chart review was performed to obtain data regarding age, body mass index, body mass index loss, weight loss, reason for weight loss, comorbidities, nicotine, and additional procedures, postoperative sensitive on the NAC transplants and complications. RESULTS: None of the free-nipple grafts were lost. Forty (95%) of 42 patients with mastectomy had a resensitivity on the NAC. CONCLUSIONS: For pseudogynecomastia, the treatment algorithm of the Gusenoff classification should be modified and adapted according to our recommendations to achieve more optimal masculine results.


Asunto(s)
Algoritmos , Toma de Decisiones Clínicas/métodos , Ginecomastia/cirugía , Mamoplastia/métodos , Mastectomía/métodos , Pérdida de Peso , Adulto , Estudios de Seguimiento , Ginecomastia/clasificación , Ginecomastia/diagnóstico , Ginecomastia/etiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
2.
Histochem Cell Biol ; 148(4): 425-433, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28478588

RESUMEN

Aneurysm formation occurs most frequently as abdominal aortic aneurysm (AAA), but is also seen in other localizations like thoracic or peripheral aneurysm. While initial mechanisms for aneurysm induction remain elusive, observations from AAA samples show transmural inflammation with proteolytic imbalance and repair mechanisms triggered by the innate immune system. However, limited knowledge exists about aneurysm pathology, especially for others than AAA. We compared 42 AAA, 15 popliteal, 3 ascending aortic, five iliac, two femoral, two brachial, one visceral and two secondary aneurysms to non-aneurysmatic controls by histologic analysis, immunohistochemistry and cytokine expression. Muscular and elastic type arteries show a uniform way of aneurysm formation. All samples show similar morphology. The changes compared to controls are distinct and include matrix remodeling with smooth muscle cell phenotype switch and angiogenesis, adventitial lymphoid cell accumulation and M1 macrophage homing together with neutrophil inflammation. Inflammatory cytokines are up-regulated accordingly. Comparative analysis of different disease entities can identify characteristic pathomechanisms. The phenotype of human advanced aneurysm disease is observed for elastic and muscular type arteries, does not differ between disease localizations and might, thus, be a unique response of the vasculature to the still unknown trigger of aneurysm formation.


Asunto(s)
Aneurisma de la Aorta Abdominal/metabolismo , Aneurisma de la Aorta Abdominal/patología , Arterias/metabolismo , Arterias/patología , Aneurisma de la Aorta Abdominal/cirugía , Citocinas/biosíntesis , Citocinas/metabolismo , Humanos , Inmunohistoquímica
3.
J Vasc Surg ; 66(5): 1553-1564.e6, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-27720318

RESUMEN

OBJECTIVE: Abdominal aortic aneurysm (AAA) is a frequent, potentially life-threatening, disease that can only be treated by surgical means such as open surgery or endovascular repair. No alternative treatment is currently available, and despite expanding knowledge about the pathomechanism, clinical trials on medical aneurysm abrogation have led to inconclusive results. The heterogeneity of human AAA based on histologic examination is thereby generally neglected. In this study we aimed to further elucidate the role of these differences in aneurysm disease. METHODS: Tissue samples from AAA and popliteal artery aneurysm patients were examined by histomorphologic analysis, immunohistochemistry, Western blot, and polymerase chain reaction. The results were correlated with clinical data such as aneurysm diameter and laboratory results. RESULTS: The morphology of human AAA vessel wall probes varies tremendously based on the grade of inflammation. This correlates with increasing intima/media thickness and upregulation of the vascular endothelial growth factor cascade but not with any clinical parameter or the aneurysm diameter. The phenotypic switch of vascular smooth muscle cells occurred regardless of the inflammatory state and expressional changes of the transcription factors Kruppel-like factor-4 and transforming growth factor-ß lead to differential protein localization in aneurysmal compared with control arteries. These changes were in similar manner also observed in samples from popliteal artery aneurysms, which, however, showed a more homogenous phenotype. CONCLUSIONS: Heterogeneity of AAA vessel walls based on inflammatory morphology does not correlate with AAA diameter yet harbors specific implications for basic research and possible aneurysm detection.


Asunto(s)
Aneurisma/patología , Aneurisma de la Aorta Abdominal/patología , Desdiferenciación Celular , Inflamación/patología , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/patología , Aneurisma/diagnóstico por imagen , Aneurisma/metabolismo , Proteínas Angiogénicas/análisis , Aorta Abdominal/química , Aorta Abdominal/diagnóstico por imagen , Aorta Abdominal/patología , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/metabolismo , Aortografía/métodos , Biomarcadores/análisis , Angiografía por Tomografía Computarizada , Dilatación Patológica , Matriz Extracelular/química , Matriz Extracelular/patología , Proteínas de la Matriz Extracelular/análisis , Humanos , Inflamación/diagnóstico por imagen , Inflamación/metabolismo , Mediadores de Inflamación/análisis , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/análisis , Músculo Liso Vascular/química , Miocitos del Músculo Liso/química , Fenotipo , Arteria Poplítea/química , Arteria Poplítea/diagnóstico por imagen , Arteria Poplítea/patología , Factor de Crecimiento Transformador beta/análisis , Remodelación Vascular
4.
J Vasc Res ; 53(1-2): 49-57, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27532120

RESUMEN

Topical application of elastase to induce arterial aneurysm formation is an emerging murine model of vascular disease. In the context of aortic abdominal aneurysm (AAA), angiotensin II infusion and porcine pancreatic elastase perfusion models are commonly used today. This study, therefore, compares matrix remodeling, inflammation, and angiogenesis as distinct features of aneurysms in two models treated with intra-/extraluminal elastase. C57BL/6 mice underwent intra-/extraluminal elastase application via laparotomy and were followed up for 4 weeks. Basic histology and immunohistochemistry were performed at different time points along with transmission electron microscopy, PCR analysis, TUNEL assays, and blood analysis. Both models did not differ in aneurysm growth rate, but they showed distinct features and results depending on the way of elastase application. Extraluminal aneurysm induction preserved endothelial cell function and elastic fibers but showed ongoing acute inflammation, mainly in the adventitia. The destruction of elastic layers followed by chronic inflammation was a characteristic of intraluminal elastase perfusion, as well as medial angiogenesis, a key feature in human AAA. Different animal models harbor different features of human AAA and must, therefore, be chosen wisely. External elastase application mimics an acute inflammatory aneurysm, whereas intraluminal elastase perfusion shows chronic inflammation with angiogenesis and endothelial destruction, thus better mimicking human disease.


Asunto(s)
Aorta Abdominal/patología , Aneurisma de la Aorta Abdominal/inducido químicamente , Tejido Elástico/patología , Elastasa Pancreática , Animales , Aorta Abdominal/metabolismo , Aorta Abdominal/ultraestructura , Aneurisma de la Aorta Abdominal/genética , Aneurisma de la Aorta Abdominal/metabolismo , Aneurisma de la Aorta Abdominal/patología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Tejido Elástico/metabolismo , Tejido Elástico/ultraestructura , Células Endoteliales/patología , Humanos , Inflamación/inducido químicamente , Inflamación/metabolismo , Inflamación/patología , Masculino , Ratones Endogámicos C57BL , Neovascularización Patológica , Fenotipo , Proteolisis , Factores de Tiempo
5.
Int J Mol Sci ; 17(1)2016 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-26771601

RESUMEN

Limited comprehension of aneurysm pathology has led to inconclusive results from clinical trials. miRNAs are key regulators of post-translational gene modification and are useful tools in elucidating key features of aneurysm pathogenesis in distinct entities of abdominal and popliteal aneurysms. Here, surgically harvested specimens from 19 abdominal aortic aneurysm (AAA) and 8 popliteal artery aneurysm (PAA) patients were analyzed for miRNA expression and histologically classified regarding extracellular matrix (ECM) remodeling and inflammation. DIANA-based computational target prediction and pathway enrichment analysis verified our results, as well as previous ones. miRNA-362, -19b-1, -194, -769, -21 and -550 were significantly down-regulated in AAA samples depending on degree of inflammation. Similar or inverse regulation was found for miR-769, 19b-1 and miR-550, -21, whereas miR-194 and -362 were unaltered in PAA. In situ hybridization verified higher expression of miR-550 and -21 in PAA compared to AAA and computational analysis for target genes and pathway enrichment affirmed signal transduction, cell-cell-interaction and cell degradation pathways, in line with previous results. Despite the vague role of miRNAs for potential diagnostic and treatment purposes, the number of candidates from tissue signature studies is increasing. Tissue morphology influences subsequent research, yet comparison of distinct entities of aneurysm disease can unravel core pathways.


Asunto(s)
Aorta Abdominal/metabolismo , Aneurisma de la Aorta Abdominal/genética , MicroARNs/genética , Arteria Poplítea/metabolismo , Aorta Abdominal/patología , Aorta Abdominal/cirugía , Aneurisma de la Aorta Abdominal/metabolismo , Aneurisma de la Aorta Abdominal/patología , Aneurisma de la Aorta Abdominal/cirugía , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Regulación de la Expresión Génica , Humanos , Hibridación in Situ , Inflamación , MicroARNs/metabolismo , Especificidad de Órganos , Arteria Poplítea/patología , Arteria Poplítea/cirugía , Transducción de Señal , Transcriptoma
6.
J Biophotonics ; 9(7): 730-7, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26486822

RESUMEN

In this study, sensor surface functionalization allowing the repetitive use of a sensing device was evaluated for antibody-based detection of living bacteria using an optical planar Bragg grating sensor. To achieve regenerable immobilization of bacteria specific antibodies, the heterobifunctional cross-linker N-succinimidyl 3-(2-pyridyldithio) propionate (SPDP) was linked to an aminosilanized sensor surface and subsequently reduced to expose sulfhydryl groups enabling the covalent conjugation of SPDP-activated antibodies via disulfide bonds. The immobilization of a capture antibody specific for Staphylococcus aureus on the sensor surface as well as specific binding of S. aureus could be monitored, highlighting the applicability of optical sensors for the specific detection of large biological structures. Reusability of bacteria saturated sensors was successfully demonstrated by cleaving the antibody along with bound bacteria through reduction of disulfide bonds and subsequent re-functionalization with activated antibody, resulting in comparable sensitivity towards S. aureus.


Asunto(s)
Anticuerpos Antibacterianos/química , Anticuerpos Inmovilizados , Técnicas Biosensibles , Staphylococcus aureus/inmunología
7.
Histochem Cell Biol ; 144(1): 59-66, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25787768

RESUMEN

Neointimal hyperplasia, transplant rejection and thus immunogenicity of allografts are possible reasons for poorer patency rates in cryopreserved venous allografts for peripheral bypass surgery in comparison with autologous venous grafts. To expand the limited knowledge from human allografts, we histologically investigated allogeneic and autologous venous grafts in arterial location. Specimens of allogeneic and autologous venous graft stenosis, harvested 6 months after bypass implantation, were immunohistochemically characterized. Examination of the lesions showed a uniform morphological pattern. A continuous endothelial layer, tissue fibrosis and a thickened neointima with monocytes and dedifferentiated vascular smooth muscle cells were seen in both conduits with very low cell turnover and the absence of acute and chronic inflammation. Neoangiogenesis with CD34-positive endothelium was abundant in the vessel media. The morphological patterns of allogeneic and autologous neointima formation are similar. Consequently, neointimal hyperplasia in venous grafts may reflect a uniform physiological host response of non-immunological factors with the reasons for poorer clinical outcome of cryopreserved allografts yet to be elucidated.


Asunto(s)
Neointima/patología , Vena Safena/trasplante , Aloinjertos , Autoinjertos , Criopreservación , Endotelio Vascular/patología , Humanos , Hiperplasia , Músculo Liso Vascular/patología , Neointima/inmunología , Neovascularización Patológica
8.
Int J Pharm ; 486(1-2): 21-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25772413

RESUMEN

We evaluated an analytical setup to identify optimal preparation conditions for nanoplex formation of small molecule drugs and polyelectrolytes using ciprofloxacin (CIP) and dextran sulfate (DS) as model compounds. The suitability of isothermal titration calorimetry (ITC) as a screening tool for rational formulation optimization was assessed. Besides ITC, static and dynamic light scattering, zeta potential measurements and scanning electron microscopy were applied to analyze the influence of different salt types and ionic strengths on CIP/DS nanoplex formation. The addition of low amounts of salt, especially 0.1M NaCl, improved the formation of CIP/DS nanoplexes. The presence of low amounts of salt led to smaller and more numerous particles of higher uniformity but had no influence on the release of CIP from nanoplexes. Furthermore, the molar range, within which efficient complexation was achieved, was broader in the presence of 0.1M NaCl than in the absence of salt with overall comparable complexation efficiency. Importantly, binding affinity correlated with particle shape and morphology, potentially enabling optimization of critical quality attributes based on ITC data. Altogether, ITC along with supplemental methods is a versatile screening tool for the evaluation of nanoplex formulation conditions regarding mixing ratio, salt type and ionic strength.


Asunto(s)
Antibacterianos/química , Ciprofloxacina/química , Sulfato de Dextran/química , Nanopartículas/química , Cloruro de Sodio/química , Cloruro de Calcio/química , Calorimetría , Química Farmacéutica , Liberación de Fármacos , Microscopía Electrónica de Rastreo , Nanopartículas/ultraestructura , Concentración Osmolar , Cloruro de Potasio/química
11.
Hum Vaccin Immunother ; 10(4): 926-37, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24495867

RESUMEN

Multi-antigen immunotherapy approaches against Staphylococcus aureus are expected to have the best chance of clinical success when used in combinatorial therapy, potentially incorporating opsonic killing of bacteria and toxin neutralization. We recently reported the development of a murine monoclonal antibody specific for the immunodominant staphylococcal antigen A (IsaA), which showed highly efficient staphylococcal killing in experimental infection models of S. aureus. If IsaA-specific antibodies are to be used as a component of combination therapy in humans, the binding specificity and biological activity of the humanized variant must be preserved. Here, we describe the functional characterization of a humanized monoclonal IgG1 variant designated, hUK-66. The humanized antibody showed comparable binding kinetics to those of its murine parent, and recognized the target antigen IsaA on the surface of clinically relevant S. aureus lineages. Furthermore, hUK-66 enhances the killing of S. aureus in whole blood (a physiological environment) samples from healthy subjects and patients prone to staphylococcal infections such as diabetes and dialysis patients, and patients with generalized artery occlusive disease indicating no interference with already present natural antibodies. Taken together, these data indicate that hUK-66 mediates bacterial killing even in high risk patients and thus, could play a role for immunotherapy strategies to combat severe S. aureus infections.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Anticuerpos Monoclonales Humanizados/inmunología , Anticuerpos Monoclonales/inmunología , Antígenos Bacterianos/inmunología , Inmunoglobulina G/inmunología , Infecciones Estafilocócicas/terapia , Staphylococcus aureus/inmunología , Animales , Actividad Bactericida de la Sangre , Humanos , Ratones , Viabilidad Microbiana/efectos de los fármacos , Unión Proteica
12.
Antimicrob Agents Chemother ; 58(3): 1630-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24366730

RESUMEN

Staphylococci are the leading cause of hospital-acquired infections worldwide. Increasingly, they resist antibiotic treatment owing to the development of multiple antibiotic resistance mechanisms in most strains. Therefore, the activity and efficacy of recombinant lysostaphin as a drug against this pathogen have been evaluated. Lysostaphin exerts high levels of activity against antibiotic-resistant strains of Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA). The therapeutic value of lysostaphin has been analyzed in two different clinically relevant in vivo models, a catheter-associated infection model and a thigh infection model. We infected mice with luciferase-expressing S. aureus Xen 29, and the efficacies of lysostaphin, vancomycin, oxacillin, and combined lysostaphin-oxacillin were investigated by determining numbers of CFU, detecting bioluminescent signals, and measuring the accumulation of perfluorocarbon emulsion at the site of infection by (19)F magnetic resonance imaging. Lysostaphin treatment significantly reduced the bacterial burden in infected thigh muscles and, after systemic spreading from the catheter, in inner organs. The efficiency of lysostaphin treatment was even more pronounced in combinatorial therapy with oxacillin. These results suggest that recombinant lysostaphin may have potential as an anti-S. aureus drug worthy of further clinical development. In addition, both imaging technologies demonstrated efficacy patterns similar to that of CFU determination, although they proved to be less sensitive. Nonetheless, they served as powerful tools to provide additional information about the course and gravity of infection in a noninvasive manner, possibly allowing a reduction in the number of animals needed for research evaluation of new antibiotics in future studies.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Relacionadas con Catéteres/tratamiento farmacológico , Lisostafina/uso terapéutico , Oxacilina/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Animales , Antibacterianos/administración & dosificación , Modelos Animales de Enfermedad , Quimioterapia Combinada , Femenino , Radioisótopos de Flúor , Mediciones Luminiscentes/métodos , Lisostafina/administración & dosificación , Imagen por Resonancia Magnética , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Oxacilina/administración & dosificación , Muslo/microbiología
13.
J Med Case Rep ; 7: 75, 2013 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-23506237

RESUMEN

INTRODUCTION: Groin infections resulting in arterial bleeding due to bacterial vessel destruction are a severe challenge in vascular surgery. Patients with them most often present as emergencies and therefore need individualized reconstruction solutions. CASE PRESENTATION: Case 1 is a 67-year-old man with infectious bleeding after an autologous reconstruction of the femoral bifurcation with greater saphenous vein due to infection of a bovine pericard patch after thrombendarterectomy. Case 2 is a 35-year-old male drug addict and had severe femoral bleeding and infection after repeated intravenous and intra-arterial substance abuse. Both patients were treated with an autologous obturator bypass of the superficial femoral vein. We review the current literature and highlight our therapeutic concept of this clinical entity. CONCLUSIONS: Treatment should include systemic antibiotic medication, surgical control of the infectious site, revascularization and soft tissue repair. An extra-anatomical obturator bypass with autologous superficial femoral vein should be considered as the safest revascularization procedure in infections caused by highly pathogenic bacteria.

14.
Antimicrob Agents Chemother ; 55(1): 165-73, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20956605

RESUMEN

Staphylococcus aureus is the most common cause of nosocomial infections. Multiple antibiotic resistance and severe clinical outcomes provide a strong rationale for development of immunoglobulin-based strategies. Traditionally, novel immunological approaches against bacterial pathogens involve antibodies directed against cell surface-exposed virulence-associated epitopes or toxins. In this study, we generated a monoclonal antibody targeting the housekeeping protein IsaA, a suggested soluble lytic transglycosylase of S. aureus, and tested its therapeutic efficacy in two experimental mouse infection models. A murine anti-IsaA antibody of the IgG1 subclass (UK-66P) showed the highest binding affinity in Biacore analysis. This antibody recognized all S. aureus strains tested, including hospital-acquired and community-acquired methicillin-resistant S. aureus strains. Therapeutic efficacy in vivo in mice was analyzed using a central venous catheter-related infection model and a sepsis survival model. In both models, anti-IsaA IgG1 conferred protection against staphylococcal infection. Ex vivo, UK-66P activates professional phagocytes and induces highly microbicidal reactive oxygen metabolites in a dose-dependent manner, resulting in bacterial killing. The study provides proof of concept that monoclonal IgG1 antibodies with high affinity to the ubiquitously expressed, single-epitope-targeting IsaA are effective in the treatment of staphylococcal infection in different mouse models. Anti-IsaA antibodies might be a useful component in an antibody-based therapeutic for prophylaxis or adjunctive treatment of human cases of S. aureus infections.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Anticuerpos Antibacterianos/uso terapéutico , Antígenos Bacterianos/inmunología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/inmunología , Staphylococcus aureus/inmunología , Animales , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Masculino , Ratones , Sepsis/tratamiento farmacológico , Sepsis/microbiología , Infecciones Estafilocócicas/microbiología
15.
Int J Med Microbiol ; 300(6): 402-10, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20547101

RESUMEN

Antibiotic-resistant staphylococci are the leading cause of nosocomial infections in many hospitals around the world. Meanwhile, methicillin-resistant Staphylococcus aureus (MRSA) spread also in the community where highly virulent strains infect healthy adults that have no predisposing risk factors. Although a few novel antibiotics have been recently introduced into clinical practice, the search for alternative strategies to efficiently combat staphylococcal infections is urgently demanded to decrease the enormous burden caused by pathogenic staphylococci. In particular, immunological strategies based on vaccine development or therapeutic antibodies may significantly enhance the efficiency of anti-staphylococcal therapy. Most approaches are directed against surface components of staphylococci such as cell wall-linked adhesins, teichoic acids, capsule, the biofilm component PIA/PNAG, or soluble virulence determinants such as alpha-toxin, Panton-Valentine leukocidin, or superantigenic enterotoxins. Although 2 recent clinical trials have failed, several novel promising vaccines and therapeutic antibodies are currently in preclinical and clinical development.


Asunto(s)
Anticuerpos Antibacterianos/uso terapéutico , Inmunoterapia/métodos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Infecciones Estafilocócicas/terapia , Vacunas Estafilocócicas/uso terapéutico , Staphylococcus aureus/efectos de los fármacos , Animales , Anticuerpos Antibacterianos/inmunología , Ensayos Clínicos como Asunto , Evaluación Preclínica de Medicamentos , Humanos , Staphylococcus aureus Resistente a Meticilina/inmunología , Ratones , Infecciones Estafilocócicas/inmunología , Infecciones Estafilocócicas/microbiología , Vacunas Estafilocócicas/inmunología , Staphylococcus aureus/inmunología
16.
Int J Med Microbiol ; 300(5): 313-23, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20153694

RESUMEN

We previously identified Legionella pneumophila PlaB as the major cell-associated phospholipase A/lysophospholipase A with contact-dependent hemolytic activity. In this study, we further characterized this protein and found it to be involved in the virulence of L. pneumophila. PlaB was mainly expressed and active during exponential growth. Active PlaB was outer membrane-associated and at least in parts surface-exposed. Transport to the outer membrane was not dependent on the type I (T1SS), II (T2SS), IVB (T4BSS) or Tat secretion pathways. Furthermore, PlaB activity was not dependent on the presence of the macrophage infectivity potentiator (Mip) or the major secreted zinc metalloproteinase A (MspA). Despite the fact that PlaB is not essential for replication in protozoa or macrophage cell lines, we found that plaB mutants were impaired for replication in the lungs and dissemination to the spleen in the guinea pig infection model. Histological sections monitored less inflammation and destruction of the lung tissue after infection with the plaB mutants compared to L. pneumophila wild type. Taken together, PlaB is the first phospholipase A/lysophospholipase A with a confirmed role in the establishment of Legionnaires' disease.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/fisiología , Legionella pneumophila/enzimología , Legionella pneumophila/patogenicidad , Fosfolipasas/fisiología , Factores de Virulencia/fisiología , Animales , Proteínas de la Membrana Bacteriana Externa/genética , Modelos Animales de Enfermedad , Perfilación de la Expresión Génica , Técnicas de Inactivación de Genes , Cobayas , Histocitoquímica , Legionella pneumophila/crecimiento & desarrollo , Enfermedad de los Legionarios/microbiología , Pulmón/microbiología , Pulmón/patología , Masculino , Fosfolipasas/genética , Bazo/microbiología , Virulencia
17.
Microbes Infect ; 10(3): 217-23, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18328762

RESUMEN

The impact of the alternative sigma factor sigma B (SigB) on pathogenesis of Staphylococcus aureus is not conclusively clarified. In this study, a central venous catheter (CVC) related model of multiorgan infection was used to investigate the role of SigB for the pathogenesis of S. aureus infections and biofilm formation in vivo. Analysis of two SigB-positive wild-type strains and their isogenic mutants revealed uniformly that the wild-type was significantly more virulent than the SigB-deficient mutant. The observed difference in virulence was apparently not linked to the capability of the strains to form biofilms in vivo since wild-type and mutant strains were able to produce biofilm layers inside of the catheter. The data strongly indicate that the alternative sigma factor SigB plays a role in CVC-associated infections caused by S. aureus.


Asunto(s)
Proteínas Bacterianas/fisiología , Factor sigma/fisiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/química , Animales , Biopelículas/crecimiento & desarrollo , Cateterismo Venoso Central/efectos adversos , Masculino , Ratones , Mutación Puntual , Staphylococcus aureus/patogenicidad , Virulencia
18.
Oncol Rep ; 19(3): 761-9, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18288413

RESUMEN

Adjuvant therapies for minimal residual disease are a promising approach to improve the poor survival rates after surgery of gastric tumors. A pilot study of a neoadjuvant therapy was performed using a human monoclonal IgM antibody (SC-1) specifically inducing apoptosis in signet ring cell stomach carcinomas. However, scarce information exists on how such a treatment affects the immune system, in particular what are the effects of apoptosis induction and infusion of large amounts of IgM. Thus, the leukocyte composition (CD3, CD4, CD8, CD19, CD16+56, CD14) and several cytokines (TNF-alpha, IL6, IL12, IFN-gamma, GM-CSF, Neopterin) before and after SC-1 application were measured and compared to results of patients that underwent surgical removal of gastric carcinoma without antibody treatment. After SC-1 application, an increase in TNF-alpha and a decrease of lymphocytes and CD3+ T-cells but in the range obtained in healthy individuals was observed before surgery. After surgery, the IL6 levels increased and the TNF-alpha levels remained at the elevated level. Furthermore, there was a significant drop in lymphocytes and CD3+ T-cells. These effects were due to the surgical treatment. Other parameters did not show significant changes. It seems that the application of an apoptosis-inducing antibody prior to surgery of gastric tumors has mild if any effect on the immune system. Therefore, from an immunological point of view, the treatment with this monoclonal antibody is extremely safe.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Adulto , Anciano , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados , Antígenos CD/análisis , Citocinas/sangre , Femenino , Humanos , Inmunoglobulina M/efectos adversos , Inmunoglobulina M/uso terapéutico , Recuento de Leucocitos , Leucocitos/química , Leucocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Proyectos Piloto , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/cirugía
19.
Future Microbiol ; 2(6): 655-66, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18041906

RESUMEN

Multiple resistant staphylococci that cause significant morbidity and mortality are the leading cause of nosocomial infections. Meanwhile, methicillin-resistant Staphylococcus aureus (MRSA) also spreads in the community, where highly virulent strains infect children and young adults who have no predisposing risk factors. Although some treatment options remain, the search for new antibacterial targets and lead compounds is urgently required to ensure that staphylococcal infections can be effectively treated in the future. Promising targets for new antibacterials are gene products that are involved in essential cell functions. In addition to antibacterials, active and passive immunization strategies are being developed that target surface components of staphylococci such as cell wall-linked adhesins, teichoic acids and capsule or immunodominant antigens.


Asunto(s)
Antibacterianos/farmacología , Resistencia a la Meticilina/genética , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/uso terapéutico , Infecciones Comunitarias Adquiridas/genética , Infecciones Comunitarias Adquiridas/microbiología , Humanos , Infecciones Estafilocócicas/prevención & control , Staphylococcus aureus/clasificación , Staphylococcus aureus/genética , Staphylococcus aureus/aislamiento & purificación
20.
Langenbecks Arch Surg ; 392(6): 761-5, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17661075

RESUMEN

BACKGROUND: To our best knowledge, Panton-Valentine leucocidin (PVL)-positive methicillin-sensitive Staphylococcus aureus (MSSA) has not been described yet as cause for severe pyomyositis. CASE REPORT: We present a 23-year-old apparently healthy male patient without any typical predisposing findings who developed severe pyomyositis secondary to an operated pilonidal cyst. In the follow-up, the patient showed signs of immunocompromisation. The causative agent for purulent infection of multiple muscles was a MSSA strain harbouring PVL toxin. RESULTS: In the reported case, aggressive antibiotic and surgical treatment with additional application of immunoglobulins has lead to recovery from the disease without relapse. CONCLUSIONS: PVL-positive S. aureus are associated with skin diseases, multiple abscesses and often complicated by severe sepsis and necrotising pneumonia. Under such circumstances, the mortality rate can reach up to 75%. In addition, the PVL toxin can cause immunocompromisation and might be therefore involved in the aetiology of pyomyositis. Aggressive antibiotic and surgical treatment with additional application of immunoglobulins is recommended for treatment.


Asunto(s)
Toxinas Bacterianas/análisis , Exotoxinas/análisis , Leucocidinas/análisis , Seno Pilonidal/microbiología , Seno Pilonidal/cirugía , Complicaciones Posoperatorias/microbiología , Complicaciones Posoperatorias/cirugía , Piomiositis/microbiología , Piomiositis/cirugía , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/patogenicidad , Absceso/microbiología , Absceso/cirugía , Adulto , Técnicas Bacteriológicas , Nalgas/cirugía , Desbridamiento , Diagnóstico Diferencial , Progresión de la Enfermedad , Drenaje , Diagnóstico Precoz , Humanos , Imagen por Resonancia Magnética , Masculino , Resistencia a la Meticilina , Seno Pilonidal/diagnóstico , Complicaciones Posoperatorias/diagnóstico , Piomiositis/diagnóstico , Reoperación , Sepsis/diagnóstico , Sepsis/microbiología , Sepsis/cirugía , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/cirugía , Virulencia
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