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2.
Eur J Hybrid Imaging ; 6(1): 23, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36274071

RESUMO

Skeletal muscle metastasis from lung cancer is a rare phenomenon. In this case report, FDG PET/CT imaging detected unexpected metastatic spread in skeletal muscles from lung cancer.

3.
Ecol Modell ; 430: 1-16, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35769867

RESUMO

Meiofauna are known to have an important role on many ecological processes, although, their role in food web dynamics is often poorly understood, partially as they have been an overlooked and under sampled organism group. Here, we used quantitative food web modeling to evaluate the trophic relationship between meiofauna and their food sources and how meiofauna can mediate the carbon flow to higher trophic levels in five contrasting soft-bottom intertidal habitats (including seagrass beds, mudflats and sandflats). Carbon flow networks were constructed using the linear inverse model-Markov chain Monte Carlo technique, with increased resolution of the meiofauna compartments (i.e. biomass and feeding ecology of the different trophic groups of meiofauna) compared to most previous modeling studies. These models highlighted that the flows between the highly productive microphytobenthos and the meiofauna compartments play an important role in transferring carbon to the higher trophic levels, typically more efficiently so than macrofauna. The pathway from microphytobenthos to meiofauna represented the largest flow in all habitats and resulted in high production of meiofauna independent of habitat. All trophic groups of meiofauna, except for selective deposit feeders, had a very high dependency on microphytobenthos. Selective deposit feeders relied instead on a wider range of food sources, with varying contributions of bacteria, microphytobenthos and sediment organic matter. Ecological network analyses (e.g. cycling, throughput and ascendency) of the modeled systems highlighted the close positive relationship between the food web efficiency and the assimilation of high-quality food sources by primary consumers, e.g. meiofauna and macrofauna. Large proportions of these flows can be attributed to trophic groups of meiofauna. The sensitivity of the network properties to the representation of meiofauna in the models leads to recommending a greater attention in ecological data monitoring and integrating meiofauna into food web models.

4.
Clin Oral Investig ; 19(4): 841-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25200938

RESUMO

PURPOSE: In vitro studies have evidenced the cytotoxic effect of HEMA (2-hydroxyethyl methacrylate), the most common component of dental resin-based restorative material, which is released within the oral cavity, on eukaryotic cells such as gingival fibroblast and epithelial cells. However, since the presence of microorganisms within the oral cavity cannot be excluded and little is known about the interactions occurring between eukaryotic cells and the human oral microbiota, our attention has been addressed to investigate the effect of 3 mM HEMA on the molecular mechanisms driving the response of human gingival fibroblasts (HGFs) co-cultured with Streptococcus mutans. METHODOLOGY: HGF/S. mutans co-culture has been set up in our lab, and upon HEMA treatment, S.mutans and HGF cells' viability and adhesion along with type I collagen gene and pro-collagen I, Bax, Bcl2, nuclear factor kB (NF-kB), IkBα, pIkBα protein expression by PCR, Western blotting and ELISA assays have been investigated. RESULTS: HEMA treatment determines a significant decrease of type I collagen protein production, even in the presence of S. mutans, in parallel to a decrease of cell viability and adhesion, which seem to be regulated by NF-kB activation. In fact, when SN50, NF-kB-specific pharmacological inhibitor, is added to the culture, cell proliferation along with collagen synthesis is restored. CONCLUSION: The modulation exerted by S. mutans on the cytotoxic effect of HEMA suggests that within the oral cavity, the eukaryotic/prokaryotic cell interactions, maintaining the balance of the environment, allow HEMA to perform its adhesive and bonding function and that the use of a co-culture system, which simulates the oral cavity organization, improves the knowledge concerning the biocompatibility of this dental material.


Assuntos
Colágeno/metabolismo , Regulação para Baixo/efeitos dos fármacos , Fibroblastos/metabolismo , Gengiva/citologia , Metacrilatos/farmacologia , NF-kappa B/metabolismo , Streptococcus mutans/metabolismo , Técnicas de Cocultura/métodos , Colágeno/genética , Regulação para Baixo/genética , Fibroblastos/citologia , Humanos , Streptococcus mutans/citologia
5.
Int Endod J ; 46(12): 1164-72, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23611114

RESUMO

AIM: To investigate in coculture of human gingival fibroblasts (HGFs) and Streptococcus mitis, the molecular mechanisms driving the response to 2-hydroxyethyl methacrylate (HEMA) in terms of eukaryotic/prokaryotic cell adhesion, signal transduction and apoptosis. METHODOLOGY: The clinical strain S. mitis DS12, cultured in Trypticase soy broth was added to HGFs, obtained from fragments of healthy marginal gingival tissue and cultured in DMEM, treated with 3 mmol L(-1) 2-hydroxyethyl methacrylate (HEMA) for 48 h and processed for microscopic, western blotting and flow cytometric analyses. RESULTS: 2-hydroxyethyl methacrylate (HEMA) treatment increased the adhesion between S. mitis and HGFs, which seemed to be mediated by the PKC α/integrin ß 1 signalling system, improved by the presence of saliva. It also reduced the viability and the adhesion of HGFs to polypropylene substrate in terms of procollagen I and MMP3 expression. The presence of saliva and S. mitis reduced the number of necrotic HGFs and upregulated the expression of both procollagen I and MMP3. CONCLUSIONS: These results shed more light on the biological and molecular events occurring in vitro in a coculture model that mimics the environment of the oral cavity with HEMA treatment. The key role played by oral bacteria and saliva in preventing inflammatory and toxic processes that occur in vivo in human gingival fibroblasts upon the release of dental material monomers is confirmed.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Gengiva/enzimologia , Integrina beta1/metabolismo , Metacrilatos/farmacologia , Proteína Quinase C-alfa/metabolismo , Streptococcus mitis/fisiologia , Técnicas de Cocultura , Gengiva/citologia , Gengiva/metabolismo , Gengiva/microbiologia , Humanos
6.
J Biol Regul Homeost Agents ; 26(2): 245-51, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22824752

RESUMO

Alzheimer's Disease implies memory and cognitive impairment due to beta amyloid accumulation, presence of reactive microglia and astrocytes, loss of synapses, neural network dysfunctions and modifications of neuronal signalling. A key role in such events is played by astrocytes, which actively secrete high levels of beta amyloid protein originating from sequential cleavage of APP by alpha, beta and gamma secretases. Since inhibition of such process could represent an important strategy against the occurrence of Alzheimer's Disease, in this paper the role played by pPKC alpha in the in vitro beta amyloid production in response to gamma secretase inhibitor in rat cortical astrocytes is reported. pPKC alpha increased expression seems to be related to decreased beta amyloid production in parallel to increased astrocytes viability and decreased iNOS expression in the presence of 10 microM LY411575. Thus gamma secretase inhibitor, activating pPKC alpha intracellular pathway could be suggested to prevent or reduce downstream toxic events, representing a useful strategy to counteract Alzheimer's disease.


Assuntos
Alanina/análogos & derivados , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Peptídeos beta-Amiloides/biossíntese , Astrócitos/efeitos dos fármacos , Azepinas/farmacologia , Proteína Quinase C-alfa/fisiologia , Alanina/farmacologia , Doença de Alzheimer/tratamento farmacológico , Animais , Astrócitos/metabolismo , Células Cultivadas , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
7.
Radiology ; 221(3): 712-20, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11719667

RESUMO

PURPOSE: To evaluate the safety, local effectiveness, and long-term results of laser thermal ablation (LTA) in the treatment of small hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Ninety-two biopsies proved small HCCs (range, 0.8-4.0 cm) in 74 patients who were treated percutaneously with LTA in an outpatient clinic. A laser at a power of 5.0 W was coupled with one to four fibers that were advanced through 21-gauge needle(s) for 6-12 minutes. All lesions were evaluated with computed tomography (CT) for changes in size and vascular pattern, recurrence rates, and cumulative survival rates. Patients were examined for complications. RESULTS: No major complications occurred in 117 LTA sessions, with an average of 1.3 sessions per tumor. At 3 months, CT scans showed a nonenhancing area (complete necrosis) in 89 (97%) of 92 lesions. During follow-up (range, 6-66 months; mean, 25.3 months), 84 tumors (91%) decreased in size. The local recurrence rates (range, 1-5 years) ranged from 1.6% to 6.0%. Recurrence rates (range, 12-60 months) in other liver segments ranged from 24% to 73%. Cancer-free survival rates (range, 1-4 years) ranged from 73% to 24%. Overall survival rates were 99%, 68%, and 15% at 1, 3, and 5 years, respectively. Twenty-one patients (28%) died. CONCLUSION: LTA is a safe and effective treatment for small HCC.


Assuntos
Carcinoma Hepatocelular/cirurgia , Fotocoagulação a Laser , Neoplasias Hepáticas/cirurgia , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/mortalidade , Feminino , Humanos , Fotocoagulação a Laser/efeitos adversos , Fotocoagulação a Laser/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Taxa de Sobrevida , Tomografia Computadorizada por Raios X , Ultrassonografia
8.
Radiology ; 219(3): 669-78, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11376253

RESUMO

PURPOSE: To determine the potential long-term effectiveness of laser thermal ablation (LTA) followed by transcatheter arterial chemoembolization (TACE) in the percutaneous ablation of large hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Thirty large HCCs 3.5-9.6 cm in diameter (mean diameter, 5.2 cm) and 15 small HCCs 0.8-3.0 cm (mean diameter, 1.9 cm) were treated with ultrasonographically guided LTA with TACE and with LTA alone, respectively, in 30 patients: 19 with a solitary large HCC, and 11 with one to three additional synchronous small HCCS: A 1.064-microm neodymium yttrium-aluminium-garnet (Nd-YAG) laser at a power of 5.0 W was coupled with one to four quartz optic fibers that were advanced through 21-gauge needles. Segmental TACE was performed 30-90 days after LTA. All lesions were evaluated for change in size at computed tomography (CT), alpha-fetoprotein (AFP) levels, recurrence rates, and cumulative survival rates. RESULTS: No major complications occurred in 127 LTA sessions. CT showed complete tumor necrosis in 27 (90%) of 30 large HCCS: Twenty-eight patients were followed up for 6-41 months (mean, 17.1 months). In 25 patients, all lesions appeared stable or smaller at CT. AFP levels decreased to the normal range in all patients with high pretreatment values. The 1-, 2-, and 3-year local recurrence rate was 7% in large HCCS: Complete tumor necrosis was achieved in all 15 (100%) small HCCs; none of them recurred locally. The 1-, 2-, and 3-year cumulative survival rates were 92%, 68%, and 40%, respectively. CONCLUSION: LTA followed by TACE is an effective palliative therapy in treating large HCCS:


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Terapia a Laser , Neoplasias Hepáticas/terapia , Idoso , Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/mortalidade , Terapia Combinada , Doxorrubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Taxa de Sobrevida , Fatores de Tempo , Tomografia Computadorizada por Raios X
9.
Radiology ; 217(3): 673-7, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11110927

RESUMO

PURPOSE: To evaluate percutaneous interstitial laser photocoagulation (ILP) as a palliative treatment of recurrent thyroid carcinoma untreatable with surgery or radioiodine administration. MATERIALS AND METHODS: By using 18 resected thyroid glands, the volume and histologic pattern of ILP-induced thyroid damage were assessed. In vivo treatment feasibility was evaluated by using a low-energy laser in two volunteers before thyroidectomy for huge autonomously functioning nodules. With ultrasonographic (US) monitoring, a 21-gauge spinal needle was inserted into the thyroid nodules. A 300-microm quartz fiberoptic guide was inserted through the needle lumen, and the fiber tip was placed in direct contact with the tissue. Laser irradiation was performed with a 1.064-nm Nd:YAG laser in surgically resected glands, which were treated with 2, 3, 5, or 7 W. RESULTS: Tissue ablation was well-defined histologically, and its area was related to laser irradiation parameters (range, 0-26 mm). No correlation was found between US images and the actual extent of laser-induced lesions. Large colloid or fluid collections did not permit regular heat diffusion within the tissue. In vivo low-energy ILP was performed without technical difficulties or complications. CONCLUSION: ILP induces well-defined tissue ablation correlated with energy parameters in thyroid glands devoid of cystic areas. ILP could be a therapeutic tool for highly selected problems in thyroid tumor treatment.


Assuntos
Fotocoagulação a Laser/métodos , Glândula Tireoide/cirurgia , Análise de Variância , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Análise de Regressão , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/patologia , Ultrassonografia
10.
Ann Otol Rhinol Laryngol ; 109(3): 334-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10737321

RESUMO

Vertical midline mandibulotomy has provided a relatively simple and efficient means of obtaining access to intraoral tumors that are too large or too posterior to be removed transorally. Midline mandibulotomy has had the advantage of nerve and muscle preservation and places the osteotomy outside the typical field of radiotherapy, in contrast to lateral and paramedian osteotomies. Plate and screw fixation has been the usual means of osteosynthesis for these mandibulotomies; however, plate contouring over the symphyseal surface has been a time-consuming process. Unless the plate was contoured exactly, mandibular malalignment and malocclusion in dentulous patients has occurred. Use of parallel transverse lag screws has become a popular method of osteosynthesis for parasymphyseal fractures, and we have extended their use for mandibulotomy fixation. This paper reports our clinical experience with transverse lag screw fixation of midline mandibulotomies in 9 patients from 1994 to 1997. There were 7 men and 2 women with a mean age of 56 (range 35 to 71 years). The pathological diagnosis in all patients was squamous cell carcinoma; 8 cases were primary, and 1 patient presented with recurrent tumor. No tumors involved the mandibular periosteum. One patient had had previous radiotherapy, and 3 patients underwent postoperative radiotherapy. The mean follow-up has been 17 months (range 9 to 27). There was 1 minor complication and 1 major complication related to our technique. The major complication was a delayed nonunion of the mandibulotomy. This occurred because the 2 parallel screws were placed too close to one another, and this placement resulted in a delayed sagittal fracture of the anterior cortex and subsequent nonunion. Transverse lag screw fixation has not affected occlusion in our dentulous patients. Speech and diet were normal in the majority of our patients. Transverse lag screw fixation of the midline mandibulotomy has been a relatively safe, rapid, and reliable method for tumor access and postextirpation mandibular stabilization and has significant advantages over other current methods of mandibulotomy and fixation.


Assuntos
Parafusos Ósseos , Fixadores Internos , Mandíbula/cirurgia , Procedimentos Cirúrgicos Bucais/instrumentação , Adulto , Idoso , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Orofaríngeas/cirurgia
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