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1.
PLoS Comput Biol ; 19(10): e1011554, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37831721

RESUMO

Sensory areas of cortex respond more strongly to infrequent stimuli when these violate previously established regularities, a phenomenon known as deviance detection (DD). Previous modeling work has mainly attempted to explain DD on the basis of synaptic plasticity. However, a large fraction of cortical neurons also exhibit firing rate adaptation, an underexplored potential mechanism. Here, we investigate DD in a spiking neuronal network model with two types of short-term plasticity, fast synaptic short-term depression (STD) and slower threshold adaptation (TA). We probe the model with an oddball stimulation paradigm and assess DD by evaluating the network responses. We find that TA is sufficient to elicit DD. It achieves this by habituating neurons near the stimulation site that respond earliest to the frequently presented standard stimulus (local fatigue), which diminishes the response and promotes the recovery (global fatigue) of the wider network. Further, we find a synergy effect between STD and TA, where they interact with each other to achieve greater DD than the sum of their individual effects. We show that this synergy is caused by the local fatigue added by STD, which inhibits the global response to the frequently presented stimulus, allowing greater recovery of TA-mediated global fatigue and making the network more responsive to the deviant stimulus. Finally, we show that the magnitude of DD strongly depends on the timescale of stimulation. We conclude that highly predictable information can be encoded in strong local fatigue, which allows greater global recovery and subsequent heightened sensitivity for DD.


Assuntos
Plasticidade Neuronal , Humanos , Fadiga , Modelos Neurológicos , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia
2.
Clin Oral Investig ; 28(2): 134, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38316644

RESUMO

OBJECTIVES: Oral and maxillofacial surgery (OMFS) has to compete with other specialties for the best candidates. With the upcoming change of generations (Z and Alpha) and the movement toward gender parity of dentistry, understanding changing preferences and misconceptions is essential. MATERIAL AND METHODS: An online survey was conducted by the German-Association-of-Oral-and-Maxillofacial-Surgery (DGMKG) across German dental schools. The survey collected demographic data, academic background, and career aspirations, with a focus on OMFS. The dental student survey results were compared to a survey given to OMFS Specialists. RESULTS: 637 dental students, mainly female (70%), from 30 German universities participated. 27% had defined career aspirations post-graduation, with self-employment and academia being popular choices. 67% were unsure. Specializations leaned towards restorative dentistry (41%), orthodontics (36%), and prosthodontics (31%). While 73% showed interest in surgical practices, 20% were attracted in specializing in OMFS. Of those averse to OMFS, 78% cited long training duration as the deterrent, 12% were put off by perceived unattractive working hours. Other reasons included negative undergraduate experiences, scarcity of part-time positions, and perceived inadequate earnings. CONCLUSION: Accurate data is crucial for career decisions. OMFS societies must proactively share accurate information and guide students. OMFS offers family-friendly hours, and while its training might be longer than dental specialties, it is on par with other surgical professions. CLINICAL RELEVANCE: Dental students consistently regard OMFS as commendable career path. To guarantee sustained OMFS expertise, it is imperative to nurture this interest through dedicated academic mentorship and innovative education, thereby solidifying their professional direction.


Assuntos
Ortodontia , Cirurgia Bucal , Humanos , Feminino , Masculino , Estudantes de Odontologia , Escolha da Profissão , Cirurgia Bucal/educação , Inquéritos e Questionários , Alemanha
3.
J Oral Maxillofac Surg ; 81(5): 641-647, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36682386

RESUMO

BACKGROUND: Skin and soft tissue infections (SSTIs) are common conditions with severe and potentially life-threatening outcomes. However, the use of antibiotics to treat these infections is controversial. PURPOSE: This study was to identify the microorganisms responsible for facial SSTIs, their antibiotic sensitivities, and the therapeutic outcomes of treatment. STUDY DESIGN, SETTING, AND SAMPLE: This was a retrospective, observational cohort study conducted at a single oral and maxillofacial plastic surgery department. The study sample included 103 patients with facial SSTIs (61 men, 42 women) with a mean age of 41.8 years (standard deviation ± 20.4). PREDICTOR/EXPOSURE/INDEPENDENT VARIABLES: The predictor variables included patient characteristics, antibiotic use before the clinic visit, and the infection's site and origin. MAIN OUTCOME VARIABLE(S): The primary outcome variable was the presence of antibiotic resistance in the bacterial strains isolated from the infections. METHODS: The data were collected by reviewing the results of microbiological swabs and patient records obtained from patients with facial SSTIs. Categorical variables were described using absolute and relative frequencies, and continuous variables were described using mean and standard deviation. The association between antibiotic resistance and the predictor variables was analyzed using Pearson's χ2 test and student's t test. RESULTS: The most common cause of SSTI was an infected epidermal cyst (60.1%). Of all the microorganisms identified, 80.6% were Gram-positive, and 55.8% showed antibiotic resistance against one or more of the evaluated antibiotics, including several backup antibiotics. There were no identified risk factors that significantly influenced the probability of resistance, and there were no adverse events observed. CONCLUSION: The results of this study suggest that surgery should be the primary approach for treating SSTIs, as antibiotic administration may not be effective due to the unknown susceptibility of the causative strains. Antibiotics should be reserved for severe cases and high-risk patients, and if deemed necessary for SSTI management, a broad-spectrum antibiotic should be administered to cover resistant organisms.


Assuntos
Antibacterianos , Infecções dos Tecidos Moles , Masculino , Humanos , Feminino , Adulto , Estudos de Coortes , Antibacterianos/uso terapêutico , Infecções dos Tecidos Moles/tratamento farmacológico , Infecções dos Tecidos Moles/microbiologia , Estudos Retrospectivos , Assistência Ambulatorial
4.
Food Microbiol ; 114: 104303, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37290879

RESUMO

Listeria monocytogenes can grow under stressful conditions and contaminate various food categories. Progresss in DNA sequencing-based identification methods, such as multi-locus sequence typing (MLST) now allow for more accurate characterization of pathogens. L. monocytogenes MLST genetic diversity is reflected by the different prevalence of the "clonal complexes" (CCs) in foods or infections. Better understanding of the growth potentials of L. monocytogenes is essential for quantitative risk assessment and efficient detection across CCs genetic diversity. Using optical density measurements taken with an automated spectrophotometer, we compared the maximal growth rate and lag phase of 39 strains from 13 different CCs and various food origins, in 3 broths mimicking stresful food conditions (8 °C, aw 0.95 and pH5) and in ISO Standard enrichment broths (Half Fraser and Fraser). This is important as growth could influence risk through pathogen multiplication in food. Besides, enrichment problems could lead to a lack of detection of some CCs. Despite small differences highlighting natural intraspecific variability, our results show that growth performances of L. monocytogenes strains under the conditions tested in selective and non-selective broth do not appear to be strongly correlated to CCs and cannot explain higher CC "virulence" or prevalence.


Assuntos
Listeria monocytogenes , Listeria monocytogenes/genética , Tipagem de Sequências Multilocus , Microbiologia de Alimentos , Análise de Sequência de DNA , Variação Genética
5.
Food Microbiol ; 106: 103757, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35690455

RESUMO

In response to the massive use of biocides for controlling Listeria monocytogenes (hereafter Lm) contaminations along the food chain, strains showing biocide tolerance emerged. Here, accessory genomic elements were associated with biocide tolerance through pangenome-wide associations performed on 197 Lm strains from different lineages, ecological, geographical and temporal origins. Mobile elements, including prophage-related loci, the Tn6188_qacH transposon and pLMST6_emrC plasmid, were widespread across lineage I and II food strains and associated with tolerance to benzalkonium-chloride (BC), a quaternary ammonium compound (QAC) widely used in food processing. The pLMST6_emrC was also associated with tolerance to another QAC, the didecyldimethylammonium-chloride, displaying a pleiotropic effect. While no associations were detected for chemically reactive biocides (alcohols and chlorines), genes encoding for cell-surface proteins were associated with BC or polymeric biguanide tolerance. The latter was restricted to lineage I strains from animal and the environment. In conclusion, different genetic markers, with polygenic nature or not, appear to have driven the Lm adaptation to biocide, especially in food strains but also from animal and the environment. These markers could aid to monitor and predict the spread of biocide tolerant Lm genotypes across different ecological niches, finally reducing the risk of such strains in food industrial settings.


Assuntos
Desinfetantes , Listeria monocytogenes , Animais , Compostos de Benzalcônio/farmacologia , Cloretos , Desinfetantes/farmacologia , Farmacorresistência Bacteriana/genética , Ecossistema , Genômica
6.
J Therm Biol ; 105: 103173, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35393042

RESUMO

The behavioral and physiological mechanisms of thermoregulation and the morphological traits of lizards result in a particular range of body temperatures, which influence performance and ultimately fitness. We studied the thermal biology and locomotor performance of the lizard Liolaemus wiegmannii from the coastal dunes in the southeastern Pampas of Argentina. During the austral summer, we examined the link between thermoregulation and optimal locomotor performance. Liolaemus wiegmannii faced a stressful environment due to high risk of overheating; despite this, the species was able to achieve field body temperatures (Mean Tb ± SD = 35.58 ± 2.86 °C) than expected by chance (i.e., the null model) and suitable for sustaining its physiological performance. Locomotion in this species was thermally-sensitive, with lizards showing high-performance bouts at a relatively wide range of body temperatures (30-38 °C). Lizards exhibited a mean maximum running speed of 1.30 m/s at 37.3 °C (i.e., optimal temperature for locomotion) which was within the set point range of preferred temperature (Tset = 35.4-37.5 °C). Therefore, we found a correspondence between thermal optimum and preferred temperature. Our findings suggest that L. wiegmannii, like other lizard species with a broad distribution, is capable of performing well across a wide range of temperatures despite the spatiotemporal thermal fluctuations of the environment.


Assuntos
Lagartos , Animais , Argentina , Biologia , Temperatura Corporal , Regulação da Temperatura Corporal , Lagartos/fisiologia , Temperatura
7.
J Craniofac Surg ; 32(8): 2798-2801, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34261973

RESUMO

ABSTRACT: Hyperplasia of the coronoid process is a rare condition, potentially leading to a mechanical mouth opening restriction. Diagnostic workup and treatment will be discussed based on 5 cases. This article presents 5 cases of true coronoid process hyperplasia. In addition, we reviewed accessible literature on the topic with special attention to pathophysiologic theories, surgical approach, and postoperative physiotherapy. The improvement in the maximal intercuspidal opening ranged from 4 and 31 mm. Greater maximal intercuspidal opening improvement was connected to compliant patients, while poor outcome occurred in the case of a patient that neither followed the recommendations for physical therapy nor showed up for his follow up appointments. The success of the therapy is defined by a long-lasting and stable improvement of the mouth opening compared to the preoperative situation. In the presented cases, the outcome was strongly dependent on the patients' postoperative compliance. Based on the cases described, we conclude that a good outcome is accomplishable for patients using the methods presented, as long as patients cooperate well after surgery.Diagnostic workup in patients with trismus should be thorough to correctly diagnose rare entities such as coronoid hyperplasia. If treated correctly this condition has a good outcome, as long as the compliance of the patient is adequate.


Assuntos
Anormalidades da Boca , Trismo , Humanos , Hiperplasia/patologia , Mandíbula/patologia , Modalidades de Fisioterapia , Trismo/etiologia
8.
Anim Cogn ; 23(6): 1119-1127, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32076920

RESUMO

In a constantly changing environment, it is advantageous for animals to encode a location (such as a food source) relying on more than one single cue. A certain position might, in fact, be signalled by the presence of information acquired through different sensory modalities which may be integrated into cohesive memories. Here, we aimed to investigate multi-sensory learning capabilities and multi-modal information integration in Lasius niger ants. Individual ants were placed in a Y-maze where odour information always led to a food reward; moreover, arm and wall colour were also predictive but only when co-occurring with odour in a specific combination. At test, the odour cue was made uninformative (it was present in both arms). Ants were still able to correctly locate the reward by integrating odour with the right colour and side combination. In a second experiment, we tested whether multi-modal cue integration can take place in a single trial. To this end, ants were exposed to a rewarded odour in a single-arm maze and could experience the Y-maze (with all available cues) only once. At test (which was identical to that of Experiment 1), ants showed a slight preference for the correct colour-side combination, although not significantly different from chance level. Our results showed the capability of black garden ants to code apparently redundant contextual information and to create and rely on conditional relationships between the information available. We argue that future studies should deepen the inquiry on the timing and progression of multi-modal cue learning.


Assuntos
Formigas , Animais , Cor , Sinais (Psicologia) , Aprendizagem , Memória
9.
Neuroradiology ; 62(3): 341-346, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31838562

RESUMO

PURPOSE: To develop and evaluate a technical approach for CT-guided periradicular infiltration using quantitative needle access and guidance parameters extracted from CT scout images. METHODS: Five 3D-printed phantoms of the abdomen mimicking different patients were used to develop a technical approach for scout-guided periradicular infiltration. The needle access point, puncture depth, and needle angulation were calculated using measurements extracted from anterior-posterior and lateral CT scout images. Fifty needle placements were performed with the technique thus developed. Dose exposure and number of image acquisitions were compared with ten procedures performed using a conventional free-hand technique. Data were analyzed with the Mann-Whitney U test. RESULTS: Parameters derived solely from scout images provided adequate guidance for successful and reliable needle placement. Needle guidance was performed with the same equipment as the standard periradicular infiltration. Two scout images and 3.5 ± 2.3 (mean ± SD) single-shot images for needle positioning were acquired. Mean DLP ± SD was 3.8 ± 2.5 mGy cm. The number of single-shot acquisitions was reduced by 68% and the overall dose was reduced by 84% in comparison with the conventional free-hand technique (p < 0.0001). CONCLUSION: Scout-guided needle placement for periradicular infiltration is feasible and reduces radiation exposure significantly.


Assuntos
Radiculopatia/tratamento farmacológico , Radiografia Intervencionista/métodos , Tomografia Computadorizada por Raios X/métodos , Abdome , Humanos , Injeções Espinhais , Agulhas , Imagens de Fantasmas , Impressão Tridimensional , Punções , Doses de Radiação , Radiculopatia/diagnóstico por imagem
10.
J Appl Clin Med Phys ; 21(9): 201-208, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32721106

RESUMO

PURPOSE: To develop a customized method to produce uniform phantoms for task-based assessment of CT image quality. METHODS: Contrasts between polymethyl methacrylate (PMMA) and fructose solutions of different concentrations (240, 250, 260, 280, 290, 300, 310, 320, 330, and 340 mg/mL) were calculated. A phantom was produced by laser cutting PMMA slabs to the shape of a patient's neck. An opening of 10 mm diameter was cut into the left parapharyngeal space. An angioplasty balloon was inserted and filled with the fructose solutions to simulate low-contrast lesions. The phantom was scanned with six tube currents. Images were reconstructed with filtered back projection (FBP) and adaptive iterative dose reduction 3D (AIDR 3D). Calculated and measured contrasts were compared. The phantom was evaluated in a detectability experiment using images with 4 and 20 HU lesion contrast. RESULTS: Low-contrast lesions of 4, 9, 11, 13, 18, 20, 24, 30, 35, and 37 HU contrast were simulated. Calculated and measured contrasts correlated excellently (r = 0.998; 95% confidence interval: 0.991 to 1). The mean ± SD difference was 0.41 ± 2.32 HU (P < 0.0001). Detection accuracy and reader confidence were 62.9 ± 18.2% and 1.58 ± 0.68 for 4 HU lesion contrast and 99.6 ± 1.3% and 4.27 ± 0.92 for 20 HU lesion contrast (P < 0.0001), confirming that the method produced lesions at the threshold of detectability. CONCLUSION: A cost-effective and flexible approach was developed to create uniform phantoms with low-contrast signals. The method should facilitate access to customized phantoms for task-based image quality assessment.


Assuntos
Algoritmos , Tomografia Computadorizada por Raios X , Humanos , Imagens de Fantasmas , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador
11.
J Therm Biol ; 94: 102744, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33292985

RESUMO

Most of the literature on temperature-organism interactions rely on mean temperature (mostly air), disregarding the real complexity of this variable. There is a growing consensus about the importance of considering the temperature fluctuations as a mechanism improving organism's performance. Tadpoles are small body size ectotherm organisms that behave isothermally with their environment. As such, are good models for studying their thermal biology relative to their immediate environment. We studied six anuran tadpole species in North Patagonia, Alsodes gargola, Hylorina sylvatica, Batrachyla taeniata, Pleurodema thaul, P. bufoninum and Rhinella spinulosa, distributed in a West-East altitudinal cline with different environments and thermal conditions. We evaluated the relationship between thermal descriptors at a local scale and the thermal biology patterns of these temperate tadpoles. We estimated thermal tolerance limits and thermal sensitivity of locomotion of each species. The different aquatic environments showed important differences in local thermal conditions, associated with observed differences in the thermal traits in these tadpoles. Species exposed to lower temperature fluctuations and lower environmental mean temperatures showed lower swimming optimal temperatures and narrower thermal tolerance ranges. We found greater variability in the upper than in the lower critical limits in these Patagonian anuran tadpoles. Minimum critical temperatures were close to freezing temperature, possibly in detriment of their tolerance to high temperatures. Overall, our results suggest that these species are adapted to low temperatures. Finally, warming tolerances and predicted thermal safety margins, show that none of the studied species appear to be under thermal stress that may compromise their survival at the present time or in the near future, under a moderate climate change scenario.


Assuntos
Anuros/fisiologia , Larva/fisiologia , Termotolerância , Animais , Argentina , Locomoção , Temperatura
12.
J Therm Biol ; 88: 102485, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32125975

RESUMO

Thermoregulation in ectotherms may be modulated by climatic variability across geographic gradients. Environmental temperature varies along latitudinal clines resulting in heterogeneous thermal resource availability, which generally induces ectotherms to use compensatory mechanisms to thermoregulate. Lizards can accommodate to ambient temperature changes through a combination of adaptive evolution and behavioral and physiological plasticity. We studied the thermal ecology of the endangered endemic lizard Liolaemus multimaculatus at six different sites distributed from the northern to southern areas of the distribution (700 km) in the Atlantic dune barriers of Argentina, and even including the borders areas of the distribution range. Environmental temperatures and relative humidity showed a strong contrast between northern and southern limits of the distribution range. The northern localities had operative temperatures (Te) above the range of preferred temperatures (Tset), instead, the southern localities had large proportion of Tes within the Tset. Although these different climatic conditions may constrain the thermal biology of L. multimaculatus, individuals from all localities maintained relatively similar field body temperatures (XTb = 34.07 ± 3.02 °C), suggesting that this parameter is conservative. Thermal preference partially reflected latitudinal temperature gradient, since lizards from the two southernmost localities showed the lowest Tsel and Tset. Thermoregulatory efficiency differed among localities, since E values in the northern localities (E = 0.53-0.69) showed less variability than those of southern localities (E = 0.14-0.67). Although L. multimaculatus employed a strategy of having a conservative Tb and being able to acclimatize the thermal preference to copes with latitudinal changes in the thermal environment, other local factors, such as ecological interactions, may also impose limitations to thermoregulation and this may interfered in the interpretation of results at wider spatial scale.


Assuntos
Regulação da Temperatura Corporal , Lagartos/fisiologia , Microclima , Animais , Argentina , Geografia , Umidade , Temperatura , Vento
13.
BMC Microbiol ; 19(1): 299, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31849320

RESUMO

BACKGROUND: Listeria monocytogenes is the causative agent of listeriosis, a serious disease affecting both animals and humans. Here, multilocus sequence typing (MLST) was used to characterize the genetic diversity of Listeria monocytogenes strains isolated from the natural environment and animal clinical cases in Europe. The prevalence of clonal complexes (CCs) obtained was compared according to (i) the origin of isolation - clinical cases vs. natural environment - and (ii) the clinical form of animal listeriosis - rhombencephalitis vs. abortion. To this aim, two datasets were constructed. The clinical dataset consisted of 350 animal clinical isolates originating from France and Slovenia and supplemented with isolates from Switzerland and Great Britain. The natural environment dataset consisted of 253 isolates from the natural environment originating from Slovenia and supplemented with isolates from nine other European countries. RESULTS: For the clinical cases, CC1, CC4-CC217 and CC412 were the most prevalent in rhombencephalitis and CC1, CC37 and CC4-CC217 in abortion. The hypervirulent CC1 and CC4-CC217 prevailed in both datasets. These results indicated that livestock is constantly exposed to hypervirulent CCs. CC1 was significantly associated with a clinical origin, whereas CC9, CC29 and CC14 were associated with the natural environment. CC1 was predominant among rhombencephalitis cases both in cattle and small ruminants, and its prevalence did not differ significantly between these two groups. A novel association of CC37 and CC6 with abortion cases was revealed. CONCLUSIONS: Here, we show that CC1 and CC4-CC217 are prevalent in isolates of environmental and animal clinical origin, suggesting that ruminants are frequently exposed to hypervirulent CCs. The presence of CC4 in two mastitis cases calls for further attention due to direct threat to the consumer. We showed several associations between CCs and the origin of isolation or clinical form of listeriosis, e.g. CC37 and CC6 with abortion. This study improves our understanding of the population structure of L. monocytogenes isolates from the natural environment and animal clinical cases. Moreover, it provides a basis for future studies aiming to determine the underlying mechanisms of phenotypic traits of interest.


Assuntos
Aborto Animal/microbiologia , Microbiologia Ambiental , Variação Genética , Encefalite Infecciosa/veterinária , Listeria monocytogenes/genética , Listeriose/veterinária , Aborto Animal/epidemiologia , Animais , Técnicas de Tipagem Bacteriana , Bovinos , Europa (Continente)/epidemiologia , Feminino , Genótipo , Encefalite Infecciosa/epidemiologia , Encefalite Infecciosa/microbiologia , Listeria monocytogenes/classificação , Listeria monocytogenes/patogenicidade , Listeriose/epidemiologia , Listeriose/microbiologia , Tipagem de Sequências Multilocus , Fenótipo , Prevalência , Ruminantes/microbiologia , Virulência
14.
Eur Radiol ; 29(3): 1384-1390, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30116957

RESUMO

OBJECTIVES: To develop and evaluate methods for assembling radiopaque printed paper sheets to realistic patient phantoms for CT dose and image quality testing. METHODS: CT images of two patients were radiopaque printed with aqueous potassium iodide solution (0.6 g/ml) on paper. Two methods were developed for assembling the paper sheets to head and neck phantoms. (1) Printed sheets were fed to a paper-based 3D printer along with corresponding 3D printable STL files. (2) Paper stacks of 5-mm thickness were glued with toner, cut to the patient shape and assembled to a phantom. In a sample application study, both phantoms were examined with five different tube current settings. Images were reconstructed using filtered-back projection (FBP) and iterative reconstruction (AIDR 3D) with three strength levels. Dose length product (DLP), signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNRs) were analysed. Data were analysed using 2-way analysis of variance (ANOVA). RESULTS: Both methods achieved anthropomorphic phantoms with detailed patient anatomy. The 3D printer yielded a precise reproduction of the external patient shape, but caused visible glue artefacts. Gluing with toner avoided these artefacts and yielded more flexibility with regard to phantom size. In the sample application study, non-inferior SNR and CNR and up to 83.7% lower DLP were achieved on the phantoms with AIDR 3D compared with FBP. CONCLUSIONS: Two methods for assembling radiopaque printed paper sheets to phantoms of individual patients are presented. The sample application demonstrates potential for simulation of patient imaging and systematic CT dose and image quality assessment. KEY POINTS: • Two methods were developed to create realistic CT phantoms of individual patients from radiopaque printed paper sheets. • Analysis of five tube current and four reconstruction settings on two radiopaque 3D printed patient phantoms yielded non-inferior SNR and CNR and up to 83.7% lower dose with iterative reconstruction in comparison with filtered back projection. • Radiopaque 3D printed phantoms can simulate patients and allow systematic analysis of CT dose and image quality parameters.


Assuntos
Algoritmos , Artefatos , Cabeça/diagnóstico por imagem , Imagens de Fantasmas , Impressão Tridimensional , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Estudos de Viabilidade , Humanos
16.
Clin Oral Investig ; 23(7): 2921-2927, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30623306

RESUMO

OBJECTIVES: Aim of this study was to investigate conditions and predisposing factors for head and neck infection progress regarding the length of stay (LOS) in hospital, with special emphasis on the time of removal of the odontogenic infection focus. MATERIAL AND METHODS: A 3-year retrospective study reviewed hospital records of 248 subjects who were treated under inpatient conditions with severe odontogenic infections who received surgical incisions, drainage, and intravenous (IV) antibiotics. Outcomes measured included age, gender, involved fascial spaces, LOS, number of infected spaces, antibiotics administered, and comorbidities. We precisely recorded the time between abscess incision and focus extraction. RESULTS: Removal of infection focus (tooth) in the same stay (1 stay, n = 106; group 1; mean 6.5 days ± 3) showed significantly higher (p = 0.042) LOS than extraction in a second stay (2 stays, n = 46; group 2; 5.3 ± 3.1). Group 3 patients showed infection after removal of teeth in outpatient management (1 stay ex-op, n = 96) and presented significantly lower LOS (5.6 ± 2.5) compared to group 1 (p = 0.0216). LOS of group 3 to group 2 patients showed no significance (p = 0.668). Infection expansion and diabetes showed a significant increase of LOS. CONCLUSION: Simultaneous removal of infection focus and abscess incision leads to the lowest LOS. If tooth extraction is performed after incision, subsequent focus extraction performed in a second stay shows lower overall-LOS than extraction at the same stay at later stage. CLINICAL RELEVANCE: Multiple factors tend to increase the LOS of patients with severe head and neck infections of odontogenic origin. Our data reveals the role of removal of odontogenic focus and additionally ranks further parameters that influence the LOS. Based on our findings, decisions regarding the surgical treatment can be recommended.


Assuntos
Cabeça , Infecções , Tempo de Internação , Pescoço , Abscesso/cirurgia , Criança , Cabeça/microbiologia , Humanos , Infecções/cirurgia , Doenças da Boca/complicações , Pescoço/microbiologia , Estudos Retrospectivos
17.
Eur Radiol ; 28(11): 4818-4823, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29789910

RESUMO

OBJECTIVES: To develop an anthropomorphic phantom closely mimicking patient anatomy and to evaluate the phantom for the simulation of computed tomography (CT)-guided procedures. METHODS: Patient CT images were printed with aqueous potassium iodide solution (1 g/mL) on paper. The printed paper sheets were stacked in alternation with 1-mm thick polyethylene foam layers, cut to the patient shape and glued together to create an anthropomorphic abdomen phantom. Ten interventional radiologists performed periradicular infiltration on the phantom and rated the phantom procedure regarding different aspects of suitability for simulating CT-guided procedures. RESULTS: Radiopaque printing in combination with polyethylene foam layers achieved a phantom with detailed patient anatomy that allowed needle placement. CT-guided periradicular infiltration on the phantom was rated highly realistic for simulation of anatomy, needle navigation and overall course of the procedure. Haptics were rated as intermediately realistic. Participants strongly agreed that the phantom was suitable for training and learning purposes. CONCLUSIONS: A radiopaque 3D printed, anthropomorphic phantom provides a realistic platform for the simulation of CT-guided procedures. Future work will focus on application for training and procedure optimisation. KEY POINTS: • Radiopaque 3D printing combined with polyethylene foam achieves patient phantoms for CT-guided procedures. • Radiopaque 3D printed, anthropomorphic phantoms allow realistic simulation of CT-guided procedures. • Realistic visual guidance is a key aspect in simulation of CT-guided procedures. • Three-dimensional printed phantoms provide a platform for training and optimisation of CT-guided procedures.


Assuntos
Abdome/diagnóstico por imagem , Antropometria , Imagens de Fantasmas , Impressão Tridimensional , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Humanos
18.
Int J Colorectal Dis ; 33(5): 531-539, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29536239

RESUMO

PURPOSE: This study set out to compare the in-hospital outcomes of early elective and elective laparoscopic sigmoidectomy due to diverticulitis. METHODS: We examined the data for 378 diverticulitis patients who received an elective laparoscopic sigmoid resection between 2008 and 2012. We divided the patients into two groups: elective (group A, n = 278) and early elective (group B, n = 100). Patients in group A received surgery during the inflammation-free interval, and those in group B immediately after treating the attack with IV antibiotics for a mean period of 8 days (IQR = 3). RESULTS: Overall mortality was 0%. The mean operation duration was the same in both groups being 77.5 and 80 min respectively. There was no significant difference in the outcomes between the two groups, measured using the Clavien-Dindo classification of surgical complication (CCSC; p = 0.992). A revision due to complications was necessary in 16 cases (group A) and six cases (group B) (p = 0.820). The conversion rate to open surgery was low (six individuals in group A, vs. four in group B; p = 0.331). Patients in group B suffered significantly fewer diverticulitis attacks (three in group A, vs. two in group B; p = 0.026). CONCLUSION: Our study showed no difference in outcome between elective and early elective cases. Operation durations were optimal in both cases and were 50% shorter than those recorded in the literature. An early elective operation represents a good treatment option, especially for patients suffering from complicated diverticulitis.


Assuntos
Diverticulite/cirurgia , Procedimentos Cirúrgicos Eletivos , Emergências , Índice de Massa Corporal , Colo Sigmoide/cirurgia , Demografia , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/classificação , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Tempo
19.
J Therm Biol ; 73: 61-70, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29549992

RESUMO

Small lizards can accommodate to constraints imposed by temporal changes in ambient temperature through a combination of adaptive evolution and behavioral and physiological plasticity. Thermal physiology plasticity may compensate for climate variation and favor performance while minimizing behavioral costs in sub-optimal conditions. The Tandilia's lizard, Liolaemus tandiliensis, occurs in an isolated mountain range of the Argentinean temperate Pampas. In this study, we compared the thermal biology of L. tandiliensis between late spring (December) and mid-summer (February). The habitats' thermal quality was lower in late spring than in mid-summer. The lizard's field-body temperature (Tb) was 2-3 °C higher than the operative temperature (Te). Overall, the mean preferred temperature (Tsel) was 37.4 °C [preferred range (Tset): 36.2-38.7 °C], and was similar to other Liolaemus species. The Tset and Tsel of females in late spring were 1.8 °C lower than in mid-summer. In the case of males, the Tsel did not vary among seasons, while the Tset had a difference of 2.5 °C between seasons. Adults were moderate thermoregulators, but females were more efficient only in late spring (Emales = 0.69; Efemales = 0.58), compared to mid-summer (Emales = 0.68; Efemales = 0.50). Juveniles did not show temporal differences in temperature preferences and had a relatively higher efficiency in late spring (E = 0.38) compared to mid-summer (E = 0.28). An increased proportion of juveniles and adults shifted their Tb near to the Tset in late spring respect to mid-summer. The adults also matched their preferred temperatures to their current body temperature. These results suggest that seasonal shifts in the thermoregulatory parameters of L. tandiliensis may improve their thermoregulatory efficiency. Although temporal variation in ambient temperatures might influence the thermal biology of the studied lizards, other factors such as changes in the reproductive status may have also interfered.


Assuntos
Aclimatação , Regulação da Temperatura Corporal , Lagartos/fisiologia , Animais , Feminino , Masculino , Estações do Ano , Temperatura
20.
Appl Environ Microbiol ; 82(18): 5720-8, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27235443

RESUMO

UNLABELLED: Listeria monocytogenes is a ubiquitous bacterium that may cause the foodborne illness listeriosis. Only a small amount of data about the population genetic structure of strains isolated from food is available. This study aimed to provide an accurate view of the L. monocytogenes food strain population in France. From 1999 to 2014, 1,894 L. monocytogenes strains were isolated from food at the French National Reference Laboratory for L. monocytogenes and classified according to the five risk food matrices defined by the European Food Safety Authority (EFSA). A total of 396 strains were selected on the basis of different pulsed-field gel electrophoresis (PFGE) clusters, serotypes, and strain origins and typed by multilocus sequence typing (MLST), and the MLST results were supplemented with MLST data available from Institut Pasteur, representing human and additional food strains from France. The distribution of sequence types (STs) was compared between food and clinical strains on a panel of 675 strains. High congruence between PFGE and MLST was found. Out of 73 PFGE clusters, the two most prevalent corresponded to ST9 and ST121. Using original statistical analysis, we demonstrated that (i) there was not a clear association between ST9 and ST121 and the food matrices, (ii) serotype IIc, ST8, and ST4 were associated with meat products, and (iii) ST13 was associated with dairy products. Of the two major STs, ST121 was the ST that included the fewest clinical strains, which might indicate lower virulence. This observation may be directly relevant for refining risk analysis models for the better management of food safety. IMPORTANCE: This study showed a very useful backward compatibility between PFGE and MLST for surveillance. The results enabled better understanding of the population structure of L. monocytogenes strains isolated from food and management of the health risks associated with L. monocytogenes food strains. Moreover, this work provided an accurate view of L. monocytogenes strain populations associated with specific food matrices. We clearly showed that some STs were associated with food matrices, such as meat, meat products, and dairy products. We opened the way to source attribution modeling in order to quantify the relative importance of the main food matrices.


Assuntos
Eletroforese em Gel de Campo Pulsado , Microbiologia de Alimentos , Variação Genética , Genética Populacional , Listeria monocytogenes/classificação , Listeria monocytogenes/genética , Tipagem de Sequências Multilocus , Análise por Conglomerados , França , Humanos , Listeria monocytogenes/isolamento & purificação , Listeriose/microbiologia , Sorotipagem
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