ABSTRACT
Nanosensors present a biological monitoring method that is biocompatible, reversible, and nano-scale, and they offer many advantages over traditional organic indicators. Typical ionophore-based nanosensors incorporate nile-blue derivative pH indicators but suffer from photobleaching while quantum dot alternatives pose a potential toxicity risk. In order to address this challenge, sodium selective nanosensors containing carbon dots and a pH-sensitive quencher molecule were developed based on an ion-exchange theory and a decoupled recognition element from the pH indicator. Carbon dots were synthesized and integrated into nanosensors containing a pH-indicator, an analyte-binding ligand (ionophore), and a charge-balancing additive. These nanosensors are ion-selective against potassium (selectivity coefficient of 0.4) and lithium (selectivity coefficient of 0.9). Reversible nanosensor response to sodium is also demonstrated. The carbon dot nanosensors are resistant to changes in optical properties for at least 12 h and display stable selectivity to physiologically-relevant sodium (alpha = 0.5 of 200 mM NaCl) for a minimum of 6 days.
Subject(s)
Carbon , Ionophores , Nanotechnology , Quantum Dots , Sodium/analysis , Biocompatible Materials , Hydrogen-Ion ConcentrationABSTRACT
BACKGROUND: Sleep-related breathing disorders seriously impair well-being and increase the risk for relevant somatic and psychiatric disorders. Moreover, risk factors for sleep-related breathing disorders are highly prevalent in psychiatric patients. The aim of this study was for the first time in Germany to study the prevalence of obstructive sleep apnea syndrome (OSAS) as the most common form of sleep-related breathing disorder in patients with psychiatric disorders. METHODS: In 10 psychiatric hospitals in Germany and 1 hospital in Switzerland, a total of 249 inpatients underwent an 8channel sleep polygraphy to investigate the prevalence of sleep apnea in this group of patients. RESULTS: With a conspicuous screening result of 23.7% of the subjects, a high prevalence of sleep-related breathing disorders was found to occur among this group of patients. Male gender, higher age and high body mass index (BMI) were identified as positive risk factors for the detection of OSAS. DISCUSSION: The high prevalence indicates that sleep apnea is a common sleep disorder among psychiatric patients. Although OSAS can lead to substantial disorders of the mental state and when untreated is accompanied by serious somatic health problems, screening procedures are not part of the routine work-up in psychiatric hospitals; therefore, sleep apnea is presumably underdiagnosed in psychiatric patients. In view of the results of this and previous studies, this topic complex should be the subject of further research studies.
Subject(s)
Mental Disorders/complications , Sleep Apnea Syndromes/complications , Germany/epidemiology , Humans , Inpatients/statistics & numerical data , Male , Prevalence , Sleep Apnea Syndromes/diagnosis , Sleep Apnea Syndromes/epidemiology , Switzerland/epidemiologyABSTRACT
PURPOSE: The aim of this study was to perform an exploratory analysis of the morphological variations of mandibles at diverse states of edentulousness using tridimensional geometric morphometrics. METHODS: Twelve cadaveric mandibles were selected and divided in three groups: dentate (G1), partially edentate (G2) and totally edentate (G3). CT scans, segmentation and digital reconstruction of 3D surfaces of each specimen was made. Thirteen landmarks were defined; the measurement error was determined and 3D morphometrics exploratory analysis by principal components (PCs) and PC scores was performed. RESULTS: The principal shape variations in G2 and G3 compared to G1 can be summarized as follows: (1) decrease in the mid body mandibular height of 24% in G2 and 41% in G3, (2) decrease of symphysis height of 16% in G2 and 37% in G3, (3) a decrease in posterior mandibular height of 30% in both G1 and G2, (4) a deeper sigmoid notch also in both groups and finally (5) a widening of 7.7% in the cross sectional morphology on the symphysis in G3. CONCLUSIONS: The 3D morphometric methods, combined with surface morphing tools confirmed the main patterns of bone changes in edentulous mandibles, referenced in the literature. The average 3D mandibular morphologies of each edentulousness state group was also defined. These methods could offer more accurate definition of shape variations, which is critical in a clinical context. This study provides clinicians with highlights of 3D morphological mandibular variations at different states of edentulism and not only in 2D projections as they are currently described. The 3D surface model for each group in PDF3D file format, are include in supplementary material.
Subject(s)
Anatomic Variation , Anthropometry/methods , Jaw, Edentulous/pathology , Mandible/pathology , Mandibular Diseases/pathology , Aged , Aged, 80 and over , Anatomic Landmarks , Anatomy, Cross-Sectional , Cadaver , Female , Humans , Male , Models, AnatomicABSTRACT
Car accident simulations involving pregnant women are well documented in the literature and suggest that intra-uterine pressure could be responsible for the phenomenon of placental abruption, underlining the need for a realistic amniotic fluid model, including fluid-structure interactions (FSI). This study reports the development and validation of an amniotic fluid model using an Arbitrary Lagrangian Eulerian formulation in the LS-DYNA environment. Dedicated to the study of the mechanisms responsible for fetal injuries resulting from road accidents, the fluid model was validated using dynamic loading tests. Drop tests were performed on a deformable water-filled container at acceleration levels that would be experienced in a gravid uterus during a frontal car collision at 25 kph. During the test device braking phase, container deformation induced by inertial effects and FSI was recorded by kinematic analysis. These tests were then simulated in the LS-DYNA environment to validate a fluid model under dynamic loading, based on the container deformations. Finally, the coupling between the amniotic fluid model and an existing finite-element full-body pregnant woman model was validated in terms of pressure. To do so, experimental test results performed on four postmortem human surrogates (PMHS) (in which a physical gravid uterus model was inserted) were used. The experimental intra-uterine pressure from these tests was compared to intra uterine pressure from a numerical simulation performed under the same loading conditions. Both free fall numerical and experimental responses appear strongly correlated. The relationship between the amniotic fluid model and pregnant woman model provide intra-uterine pressure values correlated with the experimental test responses. The use of an Arbitrary Lagrangian Eulerian formulation allows the analysis of FSI between the amniotic fluid and the gravid uterus during a road accident involving pregnant women.
Subject(s)
Accidents, Traffic , Computer Simulation , Mechanical Phenomena , Uterus , Amniotic Fluid , Biomechanical Phenomena , Female , Finite Element Analysis , Humans , PregnancyABSTRACT
AIM: Anorectal manometry is the most common test used to explore anorectal disorders. The recent three-dimensional high-resolution anorectal manometry (3D-HRAM) technique appears to be able to provide new topographic information. Our objective was to develop an automated analysis of 3D-HRAM images to diagnose anal sphincter defects and compare the results with those of endoanal ultrasonography (EUS), which is considered to be the gold standard. METHOD: All patients being tested in our department for faecal incontinence or dyschezia by 3D-HRAM and EUS were eligible for the study. 3D-HRAM was used to record resting and squeeze pressure, reflecting internal and external anal sphincter function, respectively. A software platform was designed to automatically analyse the 3D-HRAM images and calculate a diagnostic score for any anal sphincter defect compared with EUS. RESULTS: A total of 206 (91% female) patients of mean age of 54 years were included in the study. A sphincter defect was diagnosed by EUS in 130 (63%). The diagnostic scores from the 3D-HRAM automated analysis for an internal anal sphincter defect showed a sensitivity of 65% and a specificity of 65%. For an external anal sphincter defect, the sensitivity was 43% and the specificity 87%. CONCLUSION: Our study developed a method based on 3D-HRAM to automatically diagnose sphincter defects, allowing a systematic and comprehensive analysis of the test recordings. Compared with EUS, the 3D-HRAM image analysis procedure revealed poor sensitivity and specificity.
Subject(s)
Anal Canal/diagnostic imaging , Automation/instrumentation , Fecal Incontinence/diagnosis , Imaging, Three-Dimensional , Manometry/methods , Adult , Aged , Anal Canal/physiopathology , Cohort Studies , Constipation/diagnosis , Endosonography/methods , Female , Humans , Male , Middle Aged , Retrospective Studies , Sensitivity and Specificity , SoftwareABSTRACT
Host genetics has a key role in susceptibility to Salmonella Typhimurium infection. We previously used N-ethyl-N-nitrosourea (ENU) mutagenesis to identify a loss-of-function mutation within the gene ubiquitin-specific peptidase 18 (Usp18(Ity9)), which confers increased susceptibility to Salmonella Typhimurium. USP18 functions to regulate type I interferon (IFN) signaling and as a protease to remove ISG15 from substrate proteins. Usp18(Ity9) mice are susceptible to infection with Salmonella Typhimurium and have increased expression and function of ISG15, but Usp18(Ity9) mice lacking Isg15 do not show improved survival with Salmonella challenge. Type I IFN signaling is increased in Usp18(Ity9) mice and inhibition of type I IFN signaling is associated with improved survival in mutant mice. Hyperactivation of type I IFN signaling leads to increased IL-10, deregulated expression of autophagy markers and elevated interleukin (IL)-1ß and IL-17. Furthermore, Usp18(Ity9) mice are more susceptible to infection with Mycobacterium tuberculosis, have increased bacterial load in the lung and spleen, elevated inflammatory cytokines and more severe lung pathology. These findings demonstrate that regulation of type I IFN signaling is the predominant mechanism affecting the susceptibility of Usp18(Ity9) mice to Salmonella infection and that hyperactivation of signaling leads to increased IL-10, deregulation of autophagic markers and increased proinflammatory cytokine production.
Subject(s)
Cytokines/metabolism , Interferon Type I/metabolism , Mutation , Salmonella Infections/genetics , Signal Transduction , Ubiquitin Thiolesterase/metabolism , Animals , Autophagy , Cytokines/genetics , Interleukin-17/genetics , Interleukin-17/metabolism , Interleukin-1beta/genetics , Interleukin-1beta/metabolism , Lung/metabolism , Lung/microbiology , Lung/pathology , Mice , Mice, Inbred C57BL , Mycobacterium Infections/genetics , Mycobacterium Infections/metabolism , Salmonella Infections/metabolism , Spleen/metabolism , Spleen/microbiology , Ubiquitin Thiolesterase/genetics , Ubiquitins/genetics , Ubiquitins/metabolismABSTRACT
In this work, we investigate the effects of stent indentation on hemodynamic indicators in stented coronary arteries. Our aim is to assess in-silico risk factors for in-stent restenosis (ISR) and thrombosis after stent implantation. The proposed model is applied to an idealized artery with Xience V stent for four indentation percentages and three mesh refinements. We analyze the patterns of hemodynamic indicators arising from different stent indentations and propose an analysis of time-averaged WSS (TAWSS), topological shear variation index (TSVI), oscillatory shear index (OSI), and relative residence time (RRT). We observe that higher indentations display higher frequency of critically low TAWSS, high TSVI, and non-physiological OSI and RRT. Furthermore, an appropriate mesh refinement is needed for accurate representation of hemodynamics in the stent vicinity. The results suggest that disturbed hemodynamics could play a role in the correlation between high indentation and ISR.
ABSTRACT
AIM: Three-dimensional high-resolution anorectal manometry (3D HRAM) is a new technique that can simultaneously provide physiological and topographical data. Our aim was to assess whether it can identify anal sphincter defects by comparing it with endoanal ultrasonography (EUS) considered as the gold standard. METHOD: An anal defect on 3D HRAM was defined as a continuous circumferential area over which the pressure was < 10 mmHg during the measurement of anal resting and voluntary contraction pressure. Inter-observer agreement was also assessed. RESULTS: A total of 100 patients (93 females) with a mean age of 53.5 ± 15.3 years were included. The positive diagnosis of an anal sphincter defect using 3D HRAM and EUS was in agreement (59.3%) (κ = 0.419) of the time for the internal anal sphincter (IAS) and (55.9%) (κ = 0.461) for the external anal sphincter (EAS). The inter-observer agreement for a diagnosis of an anal sphincter defect was (100%) (κ = 0.937) for the IAS and (95%) (κ = 0.751) for the EAS. The intra-class correlation coefficient for the extent of the defect was 0.853 for the IAS and 0.651 for the EAS. CONCLUSION: The preliminary results demonstrate some level of agreement in the diagnosis of anal sphincter defects between 3D HRAM and EUS but insufficient for 3D HRAM to be adequately reliable using the criteria chosen. The excellent inter-observer agreement, however, demonstrates that 3D HRAM is reproducible and provides a new dimension for the evaluation of sphincter function.
Subject(s)
Anus Diseases/diagnostic imaging , Anus Diseases/physiopathology , Endosonography , Imaging, Three-Dimensional , Manometry/methods , Adult , Aged , Female , Humans , Male , Middle Aged , PressureABSTRACT
Current studies suggest dysfunctional emotional processing as a key factor in the aetiology of temporomandibular disorder (TMD). Investigating facial emotion recognition (FER) may offer an elegant and reliable way to study emotional processing in patients with TMD. Twenty patients with TMD and the same number of age-, sex- and education-matched controls were measured with the Facially Expressed Emotion Labelling (FEEL) test, the 26-item Toronto Alexithymia Scale (TAS-26), the Screening for Somatoform Symptoms (SOMS-2a), the German Pain Questionnaire and the 21-item Hamilton Depression Rating Scale (HAMD). The patients had significantly lower Total FEEL Scores (P = 0·021) as compared to the controls, indicating a lower accuracy of FER. Furthermore, we were able to demonstrate significant group differences with respect to the following issues: patients were more alexithymic (P = 0·006), stated more somatoform symptoms (P < 0·004) and had higher depressive scores in the HAMD (P < 0·003). The factors alexithymia and somatisation could explain 31% (adjusted 27%) of the variance of the FEEL Scores in the sample. The estimation of the standardised regression coefficients suggests an equivalent influence of TAS-26 and SOMS-2a on the FEEL Scores, whereas 'group' (patients versus healthy controls) and depressive symptoms did not contribute significantly to the model. Our findings highlight FER deficits in patients with TMD, which are partially explained by concomitant alexithymia and somatisation. As suggested previously, impaired FER in patients with TMD may further point to probable aetiological proximities between TMD and somatoform disorders.
Subject(s)
Affective Symptoms , Emotions , Facial Expression , Recognition, Psychology , Somatoform Disorders/complications , Temporomandibular Joint Disorders/etiology , Adult , Affective Symptoms/complications , Case-Control Studies , Depression/complications , Facial Pain , Female , Humans , Interpersonal Relations , Linear Models , Male , Middle Aged , Psychiatric Status Rating Scales , Psychometrics , Statistics, Nonparametric , Temporomandibular Joint Disorders/psychologyABSTRACT
OBJECTIVE: Laboratory quality control (QC) is essential to assess the reliability of tuberculosis diagnostic testing. To provide safe QC reagents for the detection of drug-resistant Mycobacterium tuberculosis, we generated antibiotic-resistant mycobacterial strains of attenuated virulence (M. bovis bacillus Calmette-Guérin (BCG)). METHODS: Seven mono-resistant BCG strains were developed by introducing resistance-conferring mutations into wild-type BCG strains. Mutations were confirmed by dideoxynucleotide sequencing. Phenotypic resistance was quantified by microbroth dilution to determine the MIC90. The capacity of two commercial tests (GeneXpert TB/RIF and Genotype MTBDRplus) to detect resistance-conferring mutations was evaluated independently. RESULTS: Our panel included BCG strains with mutations in rpoB (S450L, I491F), katG (deletion at AA428), gyrA (D94G), rpsL (K43R) and Rv0678c (S63R). These mutations translated respectively into phenotypic resistance to rifampin (MIC ≥8 mg/L), isoniazid (MIC ≥8 mg/L), moxifloxacin (MIC 4 mg/L) and streptomycin (MIC ≥8 mg/L); the Rv0678c mutant showed decreased susceptibility to both clofazimine (MIC 4 mg/L) and bedaqualine (MIC 1 mg/L). GeneXpert (Cepheid) and Genotype MTBDRplus (Hain Lifesciences) both called the rpoB S450L strain rifampin-resistant and the I491F mutant rifampin-susceptible, as expected based on single nucleotide polymorphism positions. Likewise, MTBDRplus called the novel katG deletion mutant isoniazid susceptible despite phenotypic resistance. CONCLUSION: BCG strains engineered to be mono-resistant to anti-tuberculosis drugs can be used as safe QC reagents for tuberculosis diagnostics and drug susceptibility testing.
Subject(s)
Antitubercular Agents/pharmacology , Drug Resistance, Multiple, Bacterial , Mutation , Mycobacterium bovis/drug effects , Mycobacterium bovis/genetics , Tuberculosis, Bovine/diagnosis , Tuberculosis, Bovine/microbiology , Alleles , Amino Acid Substitution , Animals , Bacterial Proteins/genetics , Cattle , Clinical Laboratory Techniques/methods , Clinical Laboratory Techniques/standards , Codon , Dose-Response Relationship, Drug , Genotype , Humans , Mycobacterium bovis/classification , Polymorphism, Single Nucleotide , Quality Control , Rifampin/pharmacology , Tuberculosis, Bovine/drug therapyABSTRACT
Emergency Department (ED) overcrowding is a silent killer. Thus, several studies in different countries have described an increase in mortality, a decrease in the quality of care and prolonged hospital stays associated with ED overcrowding. Causes are multiple: input and in particular lack of access to lab test and imaging for general practitioners, throughput and unnecessary or time-consuming tasks, and output, in particular the availability of hospital beds for unscheduled patients. The main cause of overcrowding is waiting time for available beds in hospital wards, also known as boarding. Solutions to resolve the boarding problem are mostly organisational and require the cooperation of all department and administrative levels through efficient bed management. Elderly and polypathological patients wait longer time in ED. Internal Medicine, is the ideal specialty for these complex patients who require time for observation and evaluation. A strong partnership between the ED and the internal medicine department could help to reduce ED overcrowding by improving care pathways.
Subject(s)
Crowding , Emergency Medical Services/organization & administration , Emergency Service, Hospital , Hospital Administration , Emergency Medical Services/standards , Emergency Medical Services/trends , Emergency Service, Hospital/organization & administration , Emergency Service, Hospital/standards , Emergency Service, Hospital/trends , Health Services Accessibility/organization & administration , Health Services Accessibility/standards , Health Services Accessibility/trends , Hospital Administration/methods , Hospital Administration/standards , Hospital Administration/trends , Humans , Length of Stay/statistics & numerical data , Length of Stay/trends , Time FactorsABSTRACT
Bacille Calmette-Guérin (BCG) vaccines are live attenuated strains of Mycobacterium bovis administered to prevent tuberculosis. To better understand the differences between M. tuberculosis, M. bovis, and the various BCG daughter strains, their genomic compositions were studied by performing comparative hybridization experiments on a DNA microarray. Regions deleted from BCG vaccines relative to the virulent M. tuberculosis H37Rv reference strain were confirmed by sequencing across the missing segment of the H37Rv genome. Eleven regions (encompassing 91 open reading frames) of H37Rv were found that were absent from one or more virulent strains of M. bovis. Five additional regions representing 38 open reading frames were present in M. bovis but absent from some or all BCG strains; this is evidence for the ongoing evolution of BCG strains since their original derivation. A precise understanding of the genetic differences between closely related Mycobacteria suggests rational approaches to the design of improved diagnostics and vaccines.
Subject(s)
BCG Vaccine/genetics , Gene Deletion , Genome, Bacterial , Mycobacterium bovis/genetics , Mycobacterium tuberculosis/genetics , Oligonucleotide Array Sequence Analysis , BCG Vaccine/immunology , DNA, Bacterial/genetics , Evolution, Molecular , Genetic Variation , Humans , Mycobacterium bovis/immunology , Mycobacterium bovis/pathogenicity , Mycobacterium tuberculosis/immunology , Mycobacterium tuberculosis/pathogenicity , Nucleic Acid Hybridization , Open Reading Frames , Polymerase Chain Reaction , Vaccines, Attenuated , VirulenceABSTRACT
This study evaluated the impact of different mixing ratios and wrongly stored blends of dual-curing composite cements on Empress2 glass-ceramic crowns by means of a flexural strength test and a fracture resistance test. Thermally damaged blends and fresh blends were mixed using different mixing ratios of dual-curing Panavia F and Variolink II composite cement (2:1; 1:1; 1:1.5; 1:1.75; base/catalyst). Sixteen groups of rectangular beams of both cements (two blends, four ratios, chemical-curing, light-curing) were constructed. Their flexural strength was determined in a three-point bending test. Furthermore, 64 Empress2 all-ceramic crowns were luted onto human molars, again using fresh and thermally damaged blends as well as different mixing ratios of the luting agents. After aging, fracture resistance was investigated. The flexural strength of dual-curing composite cements was influenced to a statistically significant extent by mixing ratios and storage conditions. In particular, the chemical curing mode of these cements was affected by the thermal damage of the blends. However, this study could not demonstrate a significant impact on the fracture resistance of Empress2 glass-ceramic crowns when different mixing ratios or wrongly stored cements were used. Dual-curing composite luting agents seem to tolerate a wide range of mixing errors, but their chemical curing mode may be affected by storage errors.
Subject(s)
Crowns , Dental Porcelain , Resin Cements/chemistry , Resin Cements/chemical synthesis , Dental Restoration Failure , Dental Stress Analysis , Drug Compounding , Drug Storage , Hot Temperature , Humans , Lithium Compounds , Molar , Pliability , Self-Curing of Dental ResinsABSTRACT
This in vitro study compared the marginal adaptation of three self-adhesive composite cements with the clinically well-tried dentin adhesive system Panavia F 2.0. A total of 32 Empress 2 all-ceramic MOD-inlays (eight in each group) were luted using the self-adhesive composite cements Maxcem, Multilink Sprint, and RelyX Unicem Clicker; Panavia F 2.0 served as a clinically well-tried control. Each luted inlay underwent long-term water storage of 90 days as well as additional mechanical and thermal loading to simulate oral service. Marginal integrity was evaluated in both dentin and enamel finishing lines using scanning electron microscopy (SEM) and dye penetration tests. Dye penetration was lowest for Panavia followed by RelyX Unicem. Maxcem and Multilink showed a considerable dye penetration of up to 60%. After aging, SEM analysis revealed a reduction of "perfect margin" areas for Multilink Sprint and RelyX Unicem in enamel and for Maxcem and Multilink in dentin. Compared with the well-tried system Panavia--which was assumed as the golden standard of adhesive luting systems--only the self-adhesive luting agent RelyX Unicem showed similar results of marginal adaptation after long-term water storage.
Subject(s)
Dental Marginal Adaptation , Dentin-Bonding Agents/chemistry , Resin Cements/chemistry , Acid Etching, Dental , Coloring Agents , Dental Bonding , Dental Enamel/ultrastructure , Dental Leakage/classification , Dental Porcelain/chemistry , Dentin/ultrastructure , Humans , Inlays , Lithium Compounds/chemistry , Materials Testing , Microscopy, Electron, Scanning , Silanes/chemistry , Stress, Mechanical , Surface Properties , Temperature , Time Factors , Water/chemistryABSTRACT
PURPOSE: The aim of this study is to evaluate the morphological variability in mandibles with different types of edentulism, comparing the use of traditional morphometrics and tridimensional geometric morphometrics. METHODS: Traditional morphometrics and geometric morphometrics (GM) exploratory analysis, by principal components (PCs) and PC scores, were performed on a sample of 24 cadaveric hemi mandibles. A digital reconstruction of 3D surfaces of each specimen was obtained by CT scans segmentation. The mandibles were divided in three groups: full dentition (G1), partial edentition (G2) and total edentition (G3). The results of the two methods were compared in relation to the morphological variability determined with each method. RESULTS: Both methods were consistent in terms of morphological variability between the defined groups. The main shape variations observed were a decrease in mandibular body height, a widening of the cross sectional morphology on the symphysis, a shorten-narrowed Ramus and a deeper sigmoid notch, in the partially or totally edentition groups, compared to the full dentition group. DISCUSSION: The general patterns of morphological variations associated with edentulism that have been reported in literature could be visualized with GM method, which had not been previously used for this purpose. The GM methods could offer a more detailed definition of shape variations, which is critical in a clinical context. Moreover, GM allowed defining configurations of mean morphologies and an image library with different types of morphological variations.
Subject(s)
Tooth Loss , Tooth , Cross-Sectional Studies , Dentition , Humans , MandibleABSTRACT
From clinical knowledge, it has been established that hepatic traumas frequently lead to lethal injuries. In frontal or lateral crash situations, these injuries can be induced by pure deceleration effects or blunt trauma due to belt or steering wheel impact. Concerning the liver under frontal decelerations, how could one investigate organ behaviour leading to the injury mechanisms? This work couples experimental organ decelerations measurements (with 19 tests on cadaver trunks) and finite element simulation, provides a first analysis of the liver behaviour within the abdomen. It shows the influence of the liver attachment system that leads to liver trauma and also torsion effects between the two lobes of the liver. Injury mechanisms were evaluated through the four phases of the liver kinematics under frontal impact: (1) postero-anterior translation, (2) compression and sagittal rotation, (3) rotation in the transverse plane and (4) relaxation.
Subject(s)
Acceleration/adverse effects , Accidents, Traffic , Liver/injuries , Liver/physiopathology , Models, Biological , Wounds, Nonpenetrating/etiology , Wounds, Nonpenetrating/physiopathology , Aged , Aged, 80 and over , Computer Simulation , Female , Humans , Male , Middle AgedABSTRACT
SETTING: In Canada, tuberculosis (TB) is increasingly an urban health problem. Montreal is Canada's second-largest city and the second most frequent destination for new immigrants and refugees. OBJECTIVES: To detect spatial aggregation of cases, areas of excess incidence and local 'hot spots' of transmission in Montreal. DESIGN: We used residential addresses to geocode active TB cases reported on the Island of Montreal in 1996-2000. After a hot spot analysis suggested two areas of overconcentration, we conducted a spatial scan, with census tracts (population 2500-8000) as the primary unit of analysis and stratification by birthplace. We linked these analyses with genotyping of all available Mycobacterium tuberculosis isolates, using IS6110-RFLP and spoligotyping. RESULTS: We identified four areas of excess incidence among the foreign-born (incidence rate ratios 1.3-4.1, relative to the entire Island) and one such area among the Canadian-born (incidence rate ratio 2.3). There was partial overlap with the two hot spots. Genotyping indicated ongoing transmission among the foreign-born within the largest high-incidence zone. While this zone overlapped the area of high incidence among Canadian-born, genotyping largely excluded transmission between the two groups. CONCLUSIONS: In a city with low overall incidence, spatial and molecular analyses highlighted ongoing local transmission.
Subject(s)
DNA, Bacterial/analysis , Emigration and Immigration , Mass Screening , Mycobacterium tuberculosis/genetics , Polymorphism, Restriction Fragment Length , Residence Characteristics , Tuberculosis/transmission , Urban Health , Adult , Cluster Analysis , Emigration and Immigration/statistics & numerical data , Female , Genotype , Humans , Incidence , Male , Mass Screening/statistics & numerical data , Middle Aged , Mycobacterium tuberculosis/isolation & purification , Quebec/epidemiology , Residence Characteristics/statistics & numerical data , Retrospective Studies , Tuberculosis/epidemiology , Tuberculosis/genetics , Tuberculosis/microbiology , Urban Health/statistics & numerical dataABSTRACT
OBJECTIVES: The goal of our work is the development of a numerical model of pregnant woman in driving position. We present an application to the study of injury mechanisms during a frontal car crash for a seat belt restrained pregnant woman in driving position. MATERIALS AND METHODS: We integrated a digital representation of a pregnant uterus, foetus and placenta in a previous existing numerical model of non pregnant Human body in driving position, the Humos model. The realization of a numerical simulation of a frontal car crash enabled us to analyze the part played by the safety belt in the organic traumatisms. RESULTS: Three phases were highlighted. The first phase consists of a translation forwards of the pregnant uterus during the impact. The second phase is a rotation forwards in the sagittal plan of the pregnant uterus with for axis of rotation the posterior wall of the pubis. The third phase is a vertical adjustment coupled to a translation of the uterus towards the back. This translation leads the uterus to impact the spine. CONCLUSION: The development of a pregnant numerical model in the field of accidentology allows the analysis of organic traumatisms. That makes it possible to study the role played by the existing safety systems. This model might make it possible to develop safety systems specific to the pregnant woman.
Subject(s)
Accidents, Traffic , Models, Theoretical , Pregnancy Complications , Biomechanical Phenomena , Female , Fetus , Humans , Pregnancy , Pregnancy Trimester, Third , UterusABSTRACT
OBJECTIVES: This in vitro study tested the influence of diverse stress simulation parameters on the fracture strength of all-ceramic three-unit fixed partial dentures (FPDs). METHODS: All-ceramic FPDs made of Empress 2 (Ivoclar-Vivadent, FL) were exposed to thermal cycling and mechanical loading (TCML) with varying loading parameters such as chewing force (amount, frequency), thermal loading, lateral jaw motion, abutment material, artificial periodontium or antagonistic denture. To investigate the influence of the abutment material, human teeth, polymer abutments and alloy abutments were used. Two different TCML devices with pneumatic or weight loading were compared. FPDs without aging were used as a control. RESULTS AND SIGNIFICANCE: Combined thermal and mechanical loading significantly reduced the FPD fracture resistance from 1832N to 410N. Duplication of chewing frequency, phase load increase or additional lateral movement did not effect the results. Increasing chewing force, artificial periodontium, and antagonist or abutment material reduced the fracture resistance of the tested FPDs. Different devices with weight or pneumatic loading had no significant influence on the loading capacity of the FPDs. Artificial aging should be performed combining thermal cycling with mechanical loading. Simulation of the artificial periodontium, human antagonists and abutments should be included to achieve a significant aging.
Subject(s)
Dental Porcelain/chemistry , Denture, Partial, Fixed , Lithium Compounds/chemistry , Bite Force , Dental Abutments , Dental Alloys/chemistry , Dental Materials/chemistry , Dental Restoration Failure , Denture Design , Dentures , Humans , Mandible/physiology , Materials Testing , Models, Biological , Periodontium/physiology , Polymers/chemistry , Stress, Mechanical , Temperature , Thermodynamics , Tooth/physiology , Tooth, ArtificialABSTRACT
The objective of this cross-sectional study was to determine the minimal inhibitory concentrations of cephalosporins of the first (cefalonium and cefapirin) and fourth generation (cefquinome) against bacteria isolated from intramammary infections in dairy cows with elevated somatic cell counts in Germany. Additionally, possible regional differences of the minimal inhibitory concentrations within Germany should be evaluated. In total, 6936 quarter milk samples from cows with a somatic cell count >200,000cells/ml were taken in 43 herds. The concentrations of the first generation cephalosporins inhibiting at least 90% of the isolates of a pathogen (MIC90) were ≥64µg/ml against Gram-negative bacteria and enterococci whereas the respective MIC90 against the other Gram-positive bacteria were ≤4µg/ml. The MIC90 of cefquinome were ≥16µg/ml against Gram-negative bacteria, bacilli and enterococci, and ≤2µg/ml against the other Gram-positive bacteria. Only the minimal inhibitory concentrations against coagulase-negative staphylococci differed significantly between regions in parametric survival models with shared frailties for the herds. However, the minimal inhibitory concentrations of cefquinome against staphylococci were higher than the minimal inhibitory concentrations of the tested cephalosporins of the first generation. Therefore, cefquinome should not be the first choice to treat staphylococcal mastitis in dairy cows.