RESUMO
In the transportation engineering field, the turbulent boundary layer over a structure is one of the most relevant sources of structural vibration and emitted noise. Wind tunnels are still one of the best options for vibroacoustic experimental analyses for this specific problem. However, it is also true that this experimental method is not always affordable, due to several limitations-settings hard to control, time and money consumption, discrepancies among laboratories-that wind tunnel facilities present. It has already developed different methodologies to address this necessity, most of them based on the use of loudspeakers or shakers. In this work, an existing numerical method, called the pseudo-equivalent deterministic excitation method (PEDEM), is further developed for the experimental purpose of reproducing the experimental structural response of a panel subjected to a turbulent boundary layer (TBL) excitation, by using an equivalent rain-on-the-roof excitation instead; different formulations are used for the application of this approximated TBL excitation. The experimental application of PEDEM, here called X-PEDEM, is validated by comparison with experimental results of two different panels analysed in two different wind tunnel facilities.
RESUMO
Olfactory neuroblastoma (ONB) is an uncommon neuroendocrine sinonasal cancer associated by many authors to ectopic production of several biologically active substances. We report a case of a 31-year-old male patient who presented with idiopathic syndrome of inappropriate secretion of antidiuretic hormone (SIADH). During diagnostic work-up, a CT scan of the head was performed and an ethmoidal ONB was detected. Endoscopical surgery followed by radiotherapy was carried out. Immediately after surgery natraemia levels normalised. Five years later the patient is disease-free. To our knowledge, 17 cases of SIADH associated to ONB have been published. In nine reports, idiopathic SIADH promptly led to the diagnosis of the sinonasal mass as in our clinical case, however, in many reports, correct diagnosis was accomplished months to years later. In young patients with idiopathic inappropriate antidiuretic hormone secretion, a neuroendocrine malignancy of the sinonasal area must be excluded.
Assuntos
Estesioneuroblastoma Olfatório/complicações , Síndrome de Secreção Inadequada de HAD/etiologia , Cavidade Nasal , Neoplasias Nasais/complicações , Adulto , Humanos , MasculinoRESUMO
The aim of this paper is to describe a multidisciplinary approach including biological and particle monitoring, and microclimate analysis associated with the application of the Computational Fluid Dynamic (CFD). This approach was applied at the Palatina historical library in Parma. Monitoring was performed both in July and in December, in the absence of visitors and operators. Air microbial monitoring was performed with active and passive methods. Airborne particles with a diameter of ≥0.3, ≥0.5, ≥1 and ≥5 µm/m3, were counted by a laser particle counter. The surface contamination of shelves and manuscripts was assessed with nitrocellulose membranes. A spore trap sampler was used to identify both viable and non-viable fungal spores by optical microscope. Microbiological contaminants were analyzed through cultural and molecular biology techniques. Microclimatic parameters were also recorded. An infrared thermal camera provided information on the surface temperature of the different building materials, objects and components. Transient simulation models, for coupled heat and mass-moisture transfer, taking into account archivist and general public movements, combined with the related sensible and latent heat released into the environment, were carried out applying the CFD-FE (Finite Elements) method. Simulations of particle tracing were carried out. A wide variability in environmental microbial contamination, both for air and surfaces, was observed. Cladosporium spp., Alternaria spp., Aspergillus spp., and Penicillium spp. were the most frequently found microfungi. Bacteria such as Streptomyces spp., Bacillus spp., Sphingomonas spp., and Pseudoclavibacter as well as unculturable colonies were characterized by molecular investigation. CFD simulation results obtained were consistent with the experimental data on microclimatic conditions. The tracing and distribution of particles showed the different slice planes of diffusion mostly influenced by the convective airflow. This interdisciplinary research represents a contribution towards the definition of standardized methods for assessing the biological and microclimatic quality of indoor cultural heritage environments.
Assuntos
Microbiologia do Ar , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Monitoramento Ambiental/métodos , Bibliotecas , História , ItáliaRESUMO
Transesophageal EUS-FNA have become a useful tool in the evaluation of the mediastinum, especially during the staging work-up examination of patients with non-small-cell lung cancer (NSCLC) or other malignancies. We report a challenging case of a 53 years-old woman with an endometrial adenocarcinoma who subsequently presented with right pleural effusion, diffuse pleural thickening with few pleural lesions. The patient referred a long history of exposure to amiantum, this posing a differential diagnosis between primary pleural tumour (mesothelioma) and neoplastic pleural localization of the endometrial cancer. The cytological examination of the pleural effusion (sampled via thoracenthesis) was not adequate to reach a diagnosis. Although a right-video-assisted thoracoscopy was considered the gold standard in this clinical setting to achieve a tissue acquisition of the pleura, an EUS (as the least invasive procedure) was attempted to reach a definitive diagnosis. EUS-FNTA of the pleura was done using a 19-Gauge needle and the pathological and immunophenotypic features were diagnostic for a pleural metastasis of high-grade endometrial serous carcinoma. The patient received adjuvant chemotherapy with a complete regression of the pleural lesions. We take the opportunity of this challenging case to discuss the efficacy and safety of EUS-FNAT to sample the pleural lesions with the use of a large calibre needle if the lesion lies just under the EUS cursor. We may assume that, in selected patients, this technique could be presented as a viable option to the more invasive surgical procedure, which has been previously the gold standard for the pleural tissue acquisition.
Assuntos
Adenocarcinoma/patologia , Neoplasias do Endométrio/patologia , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Neoplasias Pleurais/secundário , Adenocarcinoma/química , Adenocarcinoma/complicações , Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Carboplatina/administração & dosagem , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Neoplasias do Endométrio/química , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Gradação de Tumores , Derrame Pleural Maligno/etiologia , Neoplasias Pleurais/química , Neoplasias Pleurais/complicações , Neoplasias Pleurais/tratamento farmacológico , Polietilenoglicóis/administração & dosagem , Tomografia por Emissão de Pósitrons , Valor Preditivo dos Testes , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
This paper briefly illustrates the basis, rules of application, and present outcome of the current World Health Organization (WHO) classification for neuroendocrine neoplasms. Established in 2010 upon the proposal from the European Neuroendocrine Tumor Society (ENETS), the WHO 2010 fostered some definitional changes (most notably the use of neuroendocrine tumor (NET) instead of carcinoid) and indicated the tools of grading and staging. Specific rules for its application were also defined. The data generated from the use of WHO 2010 classification substantially endorsed its rules and prognostic efficacy. In addition, the application demonstrated some issues, among which are the possible re-definition of the cutoff for grading G1 vs G2, as well as the possible identification of cases with somewhat different clinical behavior within the G3 neuroendocrine cancer class. Overall, since the recent introduction of WHO 2010 grading and staging, it appears wise to keep the current descriptors to avoid unnecessary confusion and to generate comparable data. Homogenous data on large series are ultimately needed to solve such issues.
Assuntos
Neoplasias do Sistema Digestório/classificação , Gradação de Tumores/normas , Estadiamento de Neoplasias/normas , Tumores Neuroendócrinos/classificação , Organização Mundial da Saúde , HumanosRESUMO
This paper provides a personal pathologist's view of how neuroendocrine tumors (NET) were perceived and defined in the last quarter of a century. In years when the Helicobacter pylori, omeprazole and the adenoma-carcinoma sequence in colon carcinogenesis significantly impacted on gastrointestinal (GI) pathology daily practice, neuroendocrine neoplasms of the GI tract passed from the original carcinoid definition to the current NET and neuroendocrine carcinoma (NEC) definitions. The development of different concepts, basic tumor biology knowledge, tools for pathology diagnosis and the various World Health Organization (WHO) classifications from 1980 through 2010 are briefly reviewed and discussed.
Assuntos
Tumor Carcinoide/história , Neoplasias Gastrointestinais/história , Tumor Carcinoide/classificação , Tumor Carcinoide/patologia , Neoplasias Gastrointestinais/classificação , Neoplasias Gastrointestinais/patologia , História do Século XX , História do Século XXI , HumanosAssuntos
Neoplasias das Glândulas Suprarrenais/secundário , Carcinoma de Células Escamosas/secundário , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Neoplasias Pulmonares/patologia , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Idoso , Carcinoma de Células Escamosas/diagnóstico por imagem , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Radiografia , Veias CavasAssuntos
Neoplasias do Mediastino/cirurgia , Equipe de Assistência ao Paciente , Sarcoma de Ewing/cirurgia , Quimiorradioterapia Adjuvante , Feminino , Humanos , Neoplasias do Mediastino/diagnóstico , Neoplasias do Mediastino/terapia , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/terapia , Toracotomia , Resultado do TratamentoRESUMO
Pancreaticoduodenectomy is the standard care for invasive ampullary adenocarcinomas. However, endoscopic snare papillectomy (ESP) might play a curative role in very selected patients. We studied a series of 15 patients with T1 ampullary adenocarcinoma who were treated by ESP alone and followed up for a mean of 29.6 ± 21.9 months (range 8 - 81 months). ESP was curative for eight patients (57.1 %). No tumor-related death was observed in patients with a cancer infiltration depth of ≤ 4 mm. According to this preliminary experience, we suggest that this measurable variable threshold should be considered as a possible basis for future large-scale studies.
Assuntos
Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Ampola Hepatopancreática , Neoplasias do Ducto Colédoco/patologia , Neoplasias do Ducto Colédoco/cirurgia , Recidiva Local de Neoplasia/cirurgia , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Duodenoscopia , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estudos RetrospectivosRESUMO
INTRODUCTION: Elastofibroma dorsi (ELD) is a rare soft tissue benign tumor of the chest wall. So far, only a few large series have been reported in the English literature and, to the best of our knowledge, radiological assessment and clinical management remain without consensus. The aim of this study is to provide, on the basis of a single-institutional, homogeneous and large experience, ample evidences to support etiological and "clinical-usefulness-grade" classification hypotheses. MATERIALS AND METHODS: We report observational information on 71 ELD cases and, on the basis of these, we discuss the clinical onset features, radiological and surgical characteristics, as well as pathological and immunohistochemical evidences. RESULTS: In the period between January 1994 and September 2009, 71 consecutive patients (23 male and 48 female; mean age: 60.2 years; standard deviation [SD] ± 8.3 years) with ELD diagnosis were surgically treated at our institution. ELD was right sided in 34 patients (47.9%), left in 25 (35.2%), and bilateral in 12 (16.9%). In nine patients, ELD were diagnosed synchronously and three metachronously. Thirty-eight patients (53.5%) had no significant symptoms; 33 (46.5%) reported a clunking sensation or a localized scapular swelling during the shoulder movements. Sixty-six (93%) patients underwent surgical excision with radical intent while in five patients, a biopsy-only procedure was undertaken. Mean hospital stay was 3.0 days (SD ± 1.2 days) with a morbidity of 10.6% (one case of major postoperative bleeding requested a surgical revision of the hemostasis). At the univariate analysis, the probability of occurrence of morbidity increases with tumor size. All operated patients are alive and well at follow-up with no sign of recurrence and complete resolution of the symptomatology. CONCLUSIONS: ELD is relatively uncommon, benign, and well controlled by radical surgery.
Assuntos
Tecido Elástico/patologia , Fibroma/diagnóstico , Neoplasias Torácicas/diagnóstico , Parede Torácica/patologia , Biópsia , Diagnóstico Diferencial , Feminino , Fibroma/cirurgia , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estudos Retrospectivos , Neoplasias Torácicas/cirurgia , Procedimentos Cirúrgicos Torácicos/métodos , Resultado do TratamentoRESUMO
Malacoplakia is a rare inflammatory condition characterized by the accumulation of benign macrophages associated with pathognomonic Michaelis-Gutmann bodies (MGBs). It is usually found in the genito-urinary tract, and has been associated with immunocompromised states. In this short report, we present 5 patients with pulmonary nodules clinically suspicious for primary or metastatic lung cancer. The histologic examination of the surgical specimens revealed a nonspecific granulomatous chronic disease, and despite the paucity of classical MGBs, a pulmonary malacoplakia was suspected. In all cases the opportunistic pathogen Rhodococcus equi (R. equi) was identified by 16S rRNA gene sequence analysis, leading to the final pathological diagnosis of malacoplakia. We conclude that pulmonary malacoplakia associated with R. equi is a rare disease affecting also immunocompetent patients. The pathogenesis and the diagnostic problems are discussed. Since infection by R. equi is treatable, the importance of its early recognition should be emphasized.
Assuntos
Infecções por Actinomycetales/diagnóstico , DNA Bacteriano/análise , DNA Ribossômico/análise , Malacoplasia/diagnóstico , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Infecções Respiratórias/diagnóstico , Rhodococcus equi/genética , Ribotipagem/métodos , Infecções por Actinomycetales/microbiologia , Infecções por Actinomycetales/patologia , Infecções por Actinomycetales/cirurgia , Idoso , Biópsia por Agulha Fina , Diagnóstico Precoce , Feminino , Humanos , Malacoplasia/microbiologia , Malacoplasia/patologia , Malacoplasia/cirurgia , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Valor Preditivo dos Testes , Infecções Respiratórias/microbiologia , Infecções Respiratórias/patologia , Infecções Respiratórias/cirurgia , Rhodococcus equi/classificação , Tomografia Computadorizada por Raios XRESUMO
Parotid gland tumours are very heterogeneous, being benign in 80% of cases, and generally arising from epithelial cells. Nevertheless, a small group of non-epithelial tumours representing just 5% of all salivary gland neoplasms has also been reported, the most common of these being haemangioma, especially in children. However, lymphomas, neuromas, neurofibromas, lipomas and sarcomas can also be found. Synovial cell sarcoma is a high grade histological variety of sarcoma and is generally located near large joints and bursae of the lower extremities, such as knee, tendon sheaths and bursal structures. It is rarely found in the head and neck region due to its lack of synovioblastic tissue. Herewith, the case of a young female, affected by a synovial sarcoma of the left parotid gland, is presented and a review is made of the literature on this rare specific localization focusing on management and outcome.
Assuntos
Neoplasias Parotídeas , Sarcoma Sinovial , Adulto , Feminino , Humanos , Neoplasias Parotídeas/diagnóstico , Neoplasias Parotídeas/cirurgia , Sarcoma Sinovial/diagnóstico , Sarcoma Sinovial/cirurgiaRESUMO
AIM: To assess the utility of diffusion-weighted imaging in diagnosing and characterizing breast malignancy. MATERIALS AND METHODS: From April 2006 to April 2009, all consecutive patients with breast cancer undergoing breast magnetic resonance imaging (MRI) and subsequent surgery in our hospital were enrolled in this study. MRI was performed using a 1.5 T MRI unit using a dedicated, bilateral, four-channel breast coil. The MRI protocol included a diffusion sequence acquired using b values of 0 and 1000 s/mm(2). For each malignant lesion the relationships between tumour grade and histology and the relative value of the apparent diffusion coefficient (ADC) were analysed. RESULTS: There were 136 female patients with 162 lesions. Histology revealed 149 invasive carcinomas and 13 ductal carcinomas in situ. There were 34 grade 1, 61 grade 2, and 67 grade 3 lesions. The mean ADC value of all malignant lesions was 1.03×10(-3) mm(2)/s. The mean ADC values for invasive and in situ carcinomas were 1.03×10(-3) mm(2)/s and 1.05×10(-3) mm(2)/s, respectively. The mean ADC values for grade 1, 2, and 3 tumours were 1.25×10(-3) mm(2)/s, 1.02×10(-3) mm(2)/s, and 0.92×10(-3) mm(2)/s, respectively. A statistically significant (p<0.001) inverse correlation was disclosed between the ADC value and the tumour grading. The mean ADC value of the "less aggressive" group of disease (G1 and in situ lesions) was 1.19×10(-3) mm(2)/s, whereas the mean ADC value of the "more aggressive" group (G2-G3 invasive carcinomas) was 0.96×10(-3) mm(2)/s (p<0.001). CONCLUSION: The study confirms the usefulness of diffusion imaging in assessing the aggressiveness of breast tumours. ADC appears to be a promising parameter in the evaluation of the degree of malignancy of breast cancer tissue.
Assuntos
Neoplasias da Mama/diagnóstico , Carcinoma in Situ/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Carcinoma in Situ/patologia , Carcinoma Ductal de Mama/patologia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Pessoa de Meia-Idade , Invasividade Neoplásica/diagnóstico , Invasividade Neoplásica/patologia , Prognóstico , Sensibilidade e Especificidade , Adulto JovemRESUMO
AIMS: A rapid detection system specific for Listeria monocytogenes and based on the polymerase chain reaction (PCR) was developed. METHODS AND RESULTS: Primers annealing to the coding region of the actA gene, critically involved in virulence and capable of discrimination between two different alleles naturally occurring in L. monocytogenes, have been utilized. The procedure was applied to recover L. monocytogenes cells in artificially contaminated fresh Italian soft cheeses (mozzarella, crescenza and ricotta). Low levels of L. monocytogenes were detected in mozzarella and crescenza homogenates (0.04-0.4 and 4 CFU g(-1), respectively) whereas in ricotta the detection limit was higher (40 CFU g(-1)). CONCLUSIONS: This PCR-based assay is highly specific as primers used recognize the DNA from different L. monocytogenes strains of clinical and food origin, while no amplification products result with any other Listeria spp. strains. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlighted a low-cost and rapid procedure that can be appropriated for the detection in real time of low L. monocytogenes levels in soft cheese.
Assuntos
Queijo/microbiologia , Microbiologia de Alimentos , Listeria monocytogenes/isolamento & purificação , Proteínas de Bactérias/genética , DNA Bacteriano/análise , Eletroforese em Gel de Ágar , Proteínas de Membrana/genética , Reação em Cadeia da Polimerase/métodos , Sensibilidade e Especificidade , Manejo de Espécimes/métodosAssuntos
Cemento Dentário/patologia , Doenças Mandibulares/patologia , Doenças Periapicais/patologia , Idoso , Doença Crônica , Diagnóstico Diferencial , Feminino , Displasia Fibrosa Óssea/diagnóstico , Humanos , Hipercementose/diagnóstico , Osteíte Deformante/diagnóstico , Osteomielite/diagnóstico , Osteosclerose/patologiaRESUMO
Guided bone regeneration (GBR) has been used recently for the regeneration of bone in conjunction with the placement of dental implants, for augmentation of resorbed alveolar crests, and to treat localized ridge deformities. Twenty-two patients with alveolar crest defects or peri-implant dehiscences participated in this study. Titanium implants were inserted, and the defects were covered with a titanium micromesh, above which was positioned an e-PTFE membrane. After healing, the 2 membranes were removed and a small specimen of the underlying tissues was retrieved with a small trephine. The postoperative healing was mostly uneventful, and only a few dehiscences with membrane exposure were observed. The space under the membranes was, in all patients, filled by a tissue with the macroscopic features of newly formed bone. No residual bone defects were observed and an increase of the alveolar width or height was observed. No untoward effects on bone regeneration were observed in the cases with membrane exposure. Histology showed that the underlying regenerated tissues were composed, in all cases, by newly formed bone. In conclusion, our results show that very satisfactory results concerning GBR techniques can be obtained even without the use of grafts under barrier membranes.
Assuntos
Aumento do Rebordo Alveolar/instrumentação , Implantação Dentária Endóssea/instrumentação , Regeneração Tecidual Guiada Periodontal/instrumentação , Adulto , Regeneração Óssea , Feminino , Humanos , Masculino , Membranas Artificiais , Pessoa de Meia-Idade , Politetrafluoretileno , Telas Cirúrgicas , TitânioRESUMO
Mixed infection with rotavirus and either Yersinia enterocolitica or Y. pseudotuberculosis was analysed in Caco-2 cells, an enterocyte-like cell line highly susceptible to these pathogens. Results showed an increase of bacterial adhesion and internalisation in rotavirus-infected cells. Increased internalisation was also seen with Escherichia coli strain HB101 (pRI203), harbouring the inv gene from Y. pseudotuberculosis, which is involved in the invasion process of host cells. In contrast, the superinfection with bacteria of Caco-2 cells pre-infected with rotavirus resulted in decreased viral antigen synthesis. Transmission electron microscopy confirmed the dual infection of enterocytes. These data suggest that rotavirus infection enhances the early interaction between host cell surfaces and enteroinvasive Yersinia spp.
Assuntos
Adesinas Bacterianas , Infecções por Rotavirus/complicações , Rotavirus/patogenicidade , Yersiniose/complicações , Yersinia enterocolitica/patogenicidade , Yersinia pseudotuberculosis/patogenicidade , Anticorpos Monoclonais , Aderência Bacteriana/imunologia , Proteínas de Bactérias/imunologia , Células CACO-2/microbiologia , Células CACO-2/ultraestrutura , Células CACO-2/virologia , Corantes/química , Enterócitos/microbiologia , Enterócitos/ultraestrutura , Enterócitos/virologia , Citometria de Fluxo , Humanos , Integrinas/imunologia , Microscopia Eletrônica , Rotavirus/ultraestrutura , Azul Tripano/química , Yersinia enterocolitica/ultraestrutura , Yersinia pseudotuberculosis/ultraestrutura , Infecções por Yersinia pseudotuberculosis/complicaçõesRESUMO
Clinical and food Listeria monocytogenes isolates, pre-exposed to mild acidic conditions, were able to readily develop acid tolerance, irrespective of their origin. We attempted to investigate the influence of acid tolerance mechanisms, either constitutive or induced, on the invasive behaviour of this facultative food-borne pathogen. Entry efficiency and intracellular growth of acid-tolerant strains were evaluated in in vitro cell models capable to mimic in vivo target cells, such as enterocytes and macrophages. An acid-adapted L. monocytogenes wild-type strain and a constitutively acid-tolerant mutant were able to enter enterocyte-like (Caco-2) cells as well as to survive and proliferate intracellularly in lipopolysaccharide-treated macrophage-like (J774.A1) cells, at a significant increased extent by respect of the non acid-adapted wild-type strain. These findings add new information about the influence of the acid tolerance response on L. monocytogenes virulence, suggesting that in acid-adapted bacteria the early events of pathogenesis which allow the colonization and the spread of bacteria in the host may be highly promoted.
Assuntos
Enterócitos/microbiologia , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/patogenicidade , Listeriose/microbiologia , Macrófagos/microbiologia , Aderência Bacteriana , Células CACO-2 , Linhagem Celular , Microbiologia de Alimentos , Humanos , Concentração de Íons de Hidrogênio , Lipopolissacarídeos/farmacologia , Ativação de Macrófagos , Macrófagos/efeitos dos fármacos , VirulênciaRESUMO
This study analysed the invasiveness of Listeria monocytogenes into enterocyte-like Caco-2 cells in which iron depletion was achieved by picolinic acid treatment. Both entry and intracellular multiplication varied depending on the endogenous iron content of bacterial and eukaryotic cells. The behaviour within enterocytes was correlated with a 10-fold increased transcription of the actA gene observed in bacterial cells grown under conditions of iron stress.
Assuntos
Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Ferro/fisiologia , Listeria monocytogenes/genética , Proteínas de Membrana/genética , Células CACO-2 , Humanos , Listeria monocytogenes/patogenicidade , VirulênciaRESUMO
The placement of an implant immediately after tooth extraction may have the following advantages: reduction in morbidity, treatment time, and treatment costs; preservation of the residual ridge width and height; optimal esthetic result; and easier definition of implant position. The aim of the present study was the presentation of a human clinical and histologic report involving a nonsubmerged implant placed in a mandibular postextraction site and removed because of persistent pain. At low-power magnification, it was possible to see that newly formed bone with wide osteocyte lacunae was present around the implant. A 1.5-mm sulcular epithelium was visible on one side of the implant, with a 0.5-mm epithelial attachment. The thickness of the supracrestal connective tissue was 3.2 mm. This connective tissue was dense, had few cells, was well vascularized, and showed no evidence of an inflammatory infiltrate. Under polarized light, it was possible to observe that the connective fibers were arranged perpendicular to the implant surface and that these fibers became parallel near the implant. These results show that human immediate postextraction implants can have a high percentage of bone-implant contact.