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Tethered cord syndrome (TCS) is characterized by leg pain and weakness, bladder and bowel dysfunction, orthopedic malformations such as scoliosis, and motor deficits caused by the fixation of the spinal cord to surrounding tissues. TCS is surgically treatable and often found in conjunction with other syndromic conditions. KBG syndrome is caused by variants in the ANKRD11 gene and is characterized by short stature, developmental delay, macrodontia, and a triangular face. The current study explores the prevalence of TCS in pediatric KBG patients and their associated signs and symptoms. Patients with KBG were surveyed for signs and symptoms associated with TCS and asked if they had been diagnosed with the syndrome. We found a high proportion of patients diagnosed with (11%) or being investigated for TCS (24%), emphasizing the need to further characterize the comorbid syndromes. No signs or symptoms clearly emerged as indicative of TCS in KBG patients, but some the prevalence of some signs and symptoms varied by sex. Male KBG patients with diagnosed TCS were more likely to have coordination issues and global delay/brain fog than their female counterparts. Understanding the presentation of TCS in KBG patients is critical for timely diagnosis and treatment.
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Anormalidades Múltiplas , Doenças do Desenvolvimento Ósseo , Deficiência Intelectual , Defeitos do Tubo Neural , Anormalidades Dentárias , Humanos , Masculino , Criança , Feminino , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/genética , Deficiência Intelectual/genética , Doenças do Desenvolvimento Ósseo/genética , Anormalidades Dentárias/genética , Fácies , Fenótipo , Proteínas Repressoras/genética , Defeitos do Tubo Neural/complicações , Defeitos do Tubo Neural/diagnóstico , Defeitos do Tubo Neural/epidemiologia , SíndromeRESUMO
PREMISE: The functional significance of leaf margins has long been debated. In this study, we explore influences of climate, leaf lobing, woodiness, and shared evolutionary history on two leaf margin traits within the genus Pelargonium. METHODS: Leaves from 454 populations of Pelargonium (161 species) were collected in the Greater Cape Floristic Region and scored for tooth presence/absence and degree of lobing. Tooth density (number of teeth per interior perimeter distance) was calculated for a subset of these. We compared five hypotheses to explain tooth presence and density using mixed effect models. RESULTS: Tooth presence/absence was best predicted by the interaction of leaf lobing and mean annual temperature (MAT), but often in patterns opposite those previously reported: species were more likely to be toothed with warmer temperatures, particularly for unlobed and highly lobed leaves. In contrast, tooth density was best predicted by the interaction of MAT and the season of most rain; density declines with temperature as consistent with expectations, but only in winter-rain dominated areas. Woody and nonwoody species within Pelargonium have similar associations between tooth presence/absence and MAT, contrary to the expectation that patterns within nonwoody species would be insignificant. CONCLUSIONS: We conclude Pelargonium leaf margins show predictable responses to climate, but these responses are complex and can contradict those found for global patterns across plant communities.
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Clima , Pelargonium , Evolução Biológica , Filogenia , Folhas de PlantaRESUMO
INTRODUCTION: Ingestion of buprenorphine by young children is on the rise and can lead to life-threatening consequences and death. Exposure most often occurs when a child acquires the medication intended for adult use. However, buprenorphine is also prescribed by veterinarians and may be sent home, typically in non-child-resistant packaging, to be administered to the family pet. CASE: A previously healthy 2-year-old girl weighing 11.36 kg was found with a 1-mL syringe containing 0.6 mg/mL of buprenorphine in her mouth. The syringe had been in a plastic bag provided to the family by their veterinarian for the family dog. She was hospitalized for 24 hours but remained asymptomatic and was discharged healthy. This type of exposure to buprenorphine has not previously been described in the literature. CONCLUSIONS: Having this unsecured medication in the home increases the potential risk of exposure for young children and associated health consequences. Pediatricians should be aware of the potential dangers that veterinary pharmaceuticals can pose and educate parents about proper storage of medications. In addition, veterinarians should take extra precautions when dispensing these medications to pet owners with children.
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Buprenorfina/intoxicação , Drogas Veterinárias/intoxicação , Feminino , Humanos , LactenteRESUMO
A 14-year-old girl underwent extraction of an ankylosed primary left second molar as requested by her orthodontist. The developing mandibular left second premolar (tooth 20) was unintentionally removed during extraction of the primary molar. Immediate measures were taken to reimplant tooth 20. Recall appointments over the next 10 years included monitoring of tooth 20. The patient also was followed up closely by her orthodontist during this time. Tooth 20 was monitored for proper eruption, root development, and pulpal vitality. The tooth erupted normally, and the results of pulp testing continued to be within normal limits over the course of 10 years (with the exception of a single higher electric pulp test reading than that for adjacent teeth). Root formation was completed and appeared to be within normal limits. Pulpal calcification also occurred. At the most recent recall, the tooth remained asymptomatic. Monitoring will continue during the patient's regular recall appointments. The success of this case 10 years after reimplantation supports quick action to optimize the potential for long-term clinical success. The fact that tooth 20 was at a developmental stage also likely had a favorable impact on the outcome of this case.
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Dente Molar , Erupção Dentária , Dente Decíduo , Adolescente , Dente Pré-Molar , Feminino , Seguimentos , Humanos , Tempo , Extração DentáriaRESUMO
BACKGROUND: The completion of the human genome project and the accomplished milestones in the human proteome project; as well as the progress made so far in computational bioinformatics and "big data" processing have contributed immensely to individualized/personalized medicine in the developed world. MAIN BODY: At the dawn of precision medicine, various omics-based therapies and bioengineering can now be applied accurately for the diagnosis, prognosis, treatment, and risk stratification of cancer in a manner that was hitherto not thought possible. The widespread introduction of genomics and other omics-based approaches into the postgraduate training curriculum of diverse medical and dental specialties, including pathology has improved the proficiency of practitioners in the use of novel molecular signatures in patient management. In addition, intricate details about disease disparity among different human populations are beginning to emerge. This would facilitate the use of tailor-made novel theranostic methods based on emerging molecular evidences. CONCLUSION: In this review, we examined the challenges and prospects of using currently available omics-based technologies vis-à-vis oral pathology as well as prompt cancer diagnosis and treatment in a resource limited setting.
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Rotating-hinge knee prostheses have low survivorship and high complications except in primary arthroplasties in elderly patients. We retrospectively reviewed 142 single third-generation design, rotating hinge prostheses (11 primary procedures and 131 revisions) at 57 months follow up. Implant survival was 73%. Successful two-stage reimplantation for prosthetic infection was 78.4% but new infection rate was 22%. The tibial component was durable while the femoral component was problematic. We observed only one patellar maltracking and no polyethylene wear. A third generation rotating-hinge arthroplasty reconstruction was reliable in complex problems. Outcomes in primary situations were excellent. Complications were the rule rather than the exception in revisions. With timely intervention, attention to soft tissue coverage, and realistic expectations, complications were contained and functional benefits were appreciable.
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Artroplastia do Joelho/instrumentação , Prótese do Joelho/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia do Joelho/métodos , Feminino , Humanos , Prótese do Joelho/efeitos adversos , Masculino , Pessoa de Meia-Idade , Polietileno , Recuperação de Função Fisiológica , Reoperação/estatística & dados numéricos , Estudos RetrospectivosRESUMO
Nanocomposites combining a high breakdown strength polymer and high dielectric permittivity ceramic filler have shown great potential for pulsed power applications. However, while current nanocomposites improve the dielectric permittivity of the capacitor, the gains come at the expense of the breakdown strength, which limits the ultimate performance of the capacitor. Here, we develop a new synthesis method for the growth of barium strontium titanate nanowires and demonstrate their use in ultra high energy density nanocomposites. This new synthesis process provides a facile approach to the growth of high aspect ratio nanowires with high yield and control over the stoichiometry of the solid solution. The nanowires are grown in the cubic phase with a Ba0.2Sr0.8TiO3 composition and have not been demonstrated prior to this report. The poly(vinylidene fluoride) nanocomposites resulting from this approach have high breakdown strength and high dielectric permittivity which results from the use of high aspect ratio fillers rather than equiaxial particles. The nanocomposites are shown to have an ultra high energy density of 14.86 J/cc at 450 MV/m and provide microsecond discharge time quicker than commercial biaxial oriented polypropylene capacitors. The energy density of our nanocomposites exceeds those reported in the literature for ceramic/polymer composites and is 1138% greater than the reported commercial capacitor with energy density of 1.2 J/cc at 640 MV/m for the current state of the art biaxial oriented polypropylene.
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Fontes de Energia Elétrica , Nanocompostos/química , Nanofios/química , Óxidos/química , Estrôncio/química , Titânio/química , Compostos de Bário/química , Cerâmica/química , Polímeros/química , Polipropilenos/químicaRESUMO
This study investigates the differences in mechanical properties between acrylonitrile butadiene styrene (ABS) samples produced using fused deposition modeling (FDM) and stereolithography (SLA) using ABS filaments and ABS-like resin, respectively. The central question is to determine how these distinct printing techniques affect the properties of ABS and ABS-like resin and which method delivers superior performance for specific applications, particularly in dental treatments. The evaluation methods used in this study included Shore D hardness, accelerated aging, tensile testing, Izod impact testing, flexural resistance measured by a 3-point bending test, and compression testing. Poisson's ratio was also assessed, along with microstructure characterization, density measurement, confocal microscopy, dilatometry, wettability, Fourier-transform infrared spectroscopy (FTIR), and nanoindentation. It was concluded that ABS has the same hardness in both manufacturing methods; however, the FDM process results in significantly superior mechanical properties compared to SLA. Microscopy demonstrates a more accurate sample geometry when fabricated with SLA. It is also concluded that printable ABS is suitable for applications in dentistry to fabricate models and surgical guides using the SLA and FDM methods, as well as facial protectors for sports using the FDM method.
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BACKGROUND: Amelogenesis imperfecta is a hereditary disorder affecting dental enamel. Among its phenotypes, hypocalcified AI is characterized by mineral deficiency, leading to tissue wear and, consequently, dental sensitivity. Excessive fluoride intake (through drinking water, fluoride supplements, toothpaste, or by ingesting products such as pesticides or insecticides) can lead to a condition known as dental fluorosis, which manifests as stains and teeth discoloration affecting their structure. Our recent studies have shown that extracts from Colombian native plants, Ilex guayusa and Piper marginatum, deposit mineral ions such as phosphate and orthophosphate into the dental enamel structure; however, it is unknown whether these extracts produce toxic effects on the dental pulp. OBJECTIVE: To assess cytotoxicity effects on human dental pulp stem cells (hDPSCs) exposed to extracts isolated from I. guayusa and P. marginatum and, hence, their safety for clinical use. METHODS: Raman spectroscopy, fluorescence microscopy, and flow cytometry techniques were employed. For Raman spectroscopy, hDPSCs were seeded onto nanobiochips designed to provide surface-enhanced Raman spectroscopy (SERS effect), which enhances their Raman signal by several orders of magnitude. After eight days in culture, I. guayusa and P. marginatum extracts at different concentrations (10, 50, and 100 ppm) were added. Raman measurements were performed at 0, 12, and 24 h following extract application. Fluorescence microscopy was conducted using an OLIMPUS fv1000 microscope, a live-dead assay was performed using a kit employing a BD FACS Canto TM II flow cytometer, and data analysis was determined using a FlowJo program. RESULTS: The Raman spectroscopy results showed spectra consistent with viable cells. These findings were corroborated using fluorescence microscopy and flow cytometry techniques, confirming high cellular viability. CONCLUSIONS: The analyzed extracts exhibited low cytotoxicity, suggesting that they could be safely applied on enamel for remineralization purposes. The use of nanobiochips for SERS effect improved the cell viability assessment.
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INTRODUCTION: Complications following mandibular fractures occur in 9-23% of patients. Identifying those at risk is key to prevention. Previous studies highlighted smoking, age and time from injury to presentation as risk factors but rarely recorded other possible confounders. In this paper, we use a collaborative snapshot audit to document novel risk factors and confirm established risks for complications following the treatment of mandibular fractures. METHODS: The audit was carried out by 122 OMFS trainees across the UK and Ireland (49 centres) over 6 months, coordinated by the Maxillofacial Surgery Trainees Research Collaborative. Variables recorded included basic demography, medical and social history, injury mechanism and type, management and 30-day outcome. RESULTS: Nine hundred and forty-seven (947) patients with fractured mandibles were recorded. Surgical management was carried out in 76.3%. Complications at 30 days occurred 65 (9%) of those who were managed surgically. Risk factors for complications included male sex, increasing age, any medical history, increasing number of cigarettes smoked per week, increasing alcohol use per week, worse oral hygiene and increased time from injury to presentation. DISCUSSION: We have used a large prospective snapshot audit to confirm established risk factors and identify novel risk factors. We demonstrate that time from injury to presentation is confounded by other indicators of poor health behaviour. These results are important in designing trial protocols for management of mandibular fractures and in targeting health interventions to patients at highest risk of complications.
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Fraturas Mandibulares , Humanos , Masculino , Fraturas Mandibulares/etiologia , Fraturas Mandibulares/cirurgia , Estudos Prospectivos , Fixação Interna de Fraturas/métodos , Fatores de Risco , Estudos RetrospectivosRESUMO
INTRODUCTION: Recent evidence suggests that acute emergency management of mandible fractures does not improve surgical outcomes yet is associated with increased financial burden. Current NHS policy advocating for increased adoption of day-case and semi-elective surgical procedures to reduce bed strain must be balanced with providing timely, effective treatment. Our research aims to determine patient groups currently managed via semi-elective admission and whether this can be extended to other groups to provide safe and effective management of mandible fractures. METHODS: A multi-national trainee-led audit of mandibular fractures across 49 units was completed by the Maxillofacial Trainee Research Collaborative (MTReC). Each unit prospectively collected data on fractures on admission and at follow-up. Data collected included patient demographics, behaviour, health, injury, timing to intervention and surgical complications. RESULTS: Data were collected on 947 mandibular fractures. Of the surgically managed patients, 649 (90%) were managed via acute emergency admission at the time of presentation, while 68 (10%) were managed semi-electively. Patient demographics, injury pattern and mechanism appeared to significantly affect timing of management, whereas patient behaviour, health status, timing of injury and presentation did not. Semi-elective management was associated with a significantly shorter inpatient duration (0.9 versus 1.9 days, p=0.000) with no differences in readmission, antibiotic usage or surgical complications (p=1.000, RR 1.030). CONCLUSION: Our study demonstrates the efficacy of planned admissions and semi-elective management of mandibular fractures. Simple mandibular fractures in compliant patients are suitable for semi-elective treatment. Holistic patient assessment and tailored surgical planning is crucial in determining admission modality to effectively manage mandibular trauma.
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Fraturas Mandibulares , Humanos , Fraturas Mandibulares/cirurgia , Fixação Interna de Fraturas/métodos , Antibacterianos , Resultado do Tratamento , Mandíbula , Estudos RetrospectivosRESUMO
OBJECTIVE: To evaluate the ocular reactivity of the rabbit to an intracameral injection of a dispersive ophthalmic viscosurgical device (OVD) containing various levels of bacterial endotoxin using slit-lamp biomicroscopy and laser flare photometry. DESIGN: Experimental, randomized, masked animal study. PARTICIPANTS: Thirty Dutch-Belted rabbits. METHODS: The rabbits were randomized into 6 groups to receive 0.05 ml of a hydroxypropyl methylcellulose-based dispersive OVD to which had been added one of 5 different doses of bacterial endotoxin ranging from 0.02 to 1.4 endotoxin units (EUs) or a vehicle control to both eyes. The eyes were evaluated for anterior segment inflammation at baseline and 3, 6, 9, 24, 48, and 72 hours after injection using slit-lamp biomicroscopy and laser flare photometry. MAIN OUTCOME MEASURES: Corneal clarity and anterior chamber (AC) inflammation. RESULTS: All the corneas remained clear throughout the study. Anterior chamber cells were seen at 6, 9, and 24 hours in 60% to 100% of the eyes intracamerally injected with endotoxin-containing OVD, and the response declined rapidly after 24 hours. A dose-response effect was seen between the concentration of endotoxin and the AC cell response. The aqueous flare response in eyes injected with the 2 highest doses of endotoxin was significantly greater (P<0.05) than that of controls. The amounts of fibrin observed in the AC were random, with no apparent dose-response effect seen. The flare values as obtained by laser flare photometry were consistent with the slit-lamp biomicroscopy flare findings up to grade 3+. However, the increase in laser flare value seemed to level off in eyes with more than 3+ flare. Neither measure of flare correlated with endotoxin level. CONCLUSIONS: Among the parameters evaluated in this study, the AC cell response, evaluated by slit-lamp biomicroscopy and graded using a standard grading system, was found to be the most reliable indicator of the amount of endotoxin in the dispersive OVD. The use of laser flare photometry alone does not seem to be useful in detecting an ocular response to endotoxin contamination in OVDs.
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Segmento Anterior do Olho/efeitos dos fármacos , Endotoxinas/toxicidade , Microscopia , Fotometria/métodos , Uveíte Anterior/induzido quimicamente , Animais , Segmento Anterior do Olho/patologia , Relação Dose-Resposta a Droga , Contaminação de Medicamentos , Derivados da Hipromelose , Lasers , Metilcelulose/análogos & derivados , Metilcelulose/toxicidade , Coelhos , Uveíte Anterior/diagnóstico , ViscossuplementosRESUMO
Two-stage reimplantation, with interval antibiotic-impregnated cement spacer, is the preferred treatment of prosthetic knee joint infections. In medically compromised hosts with prior failed surgeries, the outcomes are poor. Articulating spacers in such patients render the knee unstable; static spacers have risks of dislocation and extensor mechanism injury. We examined 58 infected total knee arthroplasties with extensive bone and soft tissue loss, treated with resection arthroplasty and intramedullary tibiofemoral rod and antibiotic-laden cement spacer. Thirty-seven patients underwent delayed reimplantation. Most patients (83.8%) were free from recurrent infection at mean follow-up of 29.4 months. Reinfection occurred in 16.2%, which required debridement. Twenty-one patients with poor operative risks remained with the spacer for 11.4 months. All patients, during spacer phase, had brace-free ambulation with simulated tibiofemoral fusion, without bone loss or loss of limb length.
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Antibacterianos/uso terapêutico , Artroplastia do Joelho/instrumentação , Artroplastia do Joelho/métodos , Cimentos Ósseos , Pinos Ortopédicos , Prótese do Joelho , Infecções Relacionadas à Prótese/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Desbridamento , Feminino , Seguimentos , Humanos , Incidência , Fixadores Internos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/microbiologia , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/epidemiologia , Infecções Relacionadas à Prótese/prevenção & controle , Radiografia , Recidiva , Reoperação , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Dental pain is a common complaint among the general population. Most pain is a result of traumatic injury or bacterial infection in pulpal and periapical tissues, and dental practitioners are successful at diagnosing these conditions and providing prompt relief. However, in some cases, patients continue to complain of persistent pain, which may be categorized as neuropathic. These people may avoid or neglect routine dental treatment or interventions to prevent precipitation, perpetuation or exacerbation of their pain condition, and practitioners may have to modify their procedures when managing the dental needs of this unique population.
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Assistência Odontológica , Dor Facial/terapia , Neuralgia/terapia , Anestesia Dentária , Diagnóstico Diferencial , Dor Facial/diagnóstico , Dor Facial/fisiopatologia , Humanos , Inflamação/fisiopatologia , Neuralgia/diagnóstico , Neuralgia/fisiopatologia , Nociceptividade/fisiologia , Higiene BucalRESUMO
The use of Mouthguards (MGs) in contact sports is an interesting biomedical topic. MGs are protective personal equipment made principally from the copolymer ethylene vinyl acetate (EVA). EVA is a thermoplastic whose thickness and rigidity are variables of concern for a good shock energy absorption capability in an MG. A natural fiber polymer composite is an interesting attempt for tackling these variables. Luffa cylindrica (luffa) is a sponge gourd that grows in 3D structure, which is used mainly as an ornament, a filling, or is trimmed for its use as a bathing product. In this work, a new EVA-luffa composite (EVLc) was made from commercial EVA sheets and luffa mat acting as reinforcement. FTIR, DSC, and TGA tests of EVA revealed its nature compared to literature data. A mechanical testing was applied to eight EVLc ASTM D-638 type V dumbbells (D1-D8) that showed low tensile strength values compared to EVA resistance ranges in literature. SEM images of EVLc's D1-D8 confirmed good adhesion between the reinforcement and matrix without surface treatment, and a descriptive statistical analysis indicated an intrinsic variation.
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Luffa , Desenho de Equipamento , Etilenos , Polivinil , Compostos de VinilaRESUMO
The treatment of traumatic mandibular fractures constitutes a significant part of the oral and maxillofacial trauma service's workload. There are potential variations in how they are managed. Patients are often admitted and given intravenous antibiotics prior to their definitive treatment. The evidence behind this is inconclusive. We performed a systematic review as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance/ PROSPERO Registered (CRD:42020201398) on the use of antibiotics in the management of mandibular fractures. We identified studies using a search algorithm within the OVID Gateway (including MEDLINE, PubMed, and Cochrane Collaborative). Studies analysing the possible impact of prophylactic antibiotics on traumatic mandibular fractures were eligible. The primary outcome was surgical site infection requiring any treatment beyond the normal postoperative protocol. Secondary outcomes included any complication requiring further intervention. From the 16 studies identified (3,285 patients), seven were randomised controlled clinical trials (RCTs) and nine were retrospective observational studies. We have identified significant between-study variation in choice of antibiotic regimen (timing, dosage, duration) and in reporting both primary and secondary outcomes. There was significant between-study heterogeneity (p = 0.02, I2 = 69%) and none of the assessed interventions was found to be superior. The evidence behind the use of prophylactic antibiotics in mandibular fractures is weak. A properly designed and powered RCT is needed, in order to standardise practice for the benefit of patients and healthcare systems.
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Fraturas Mandibulares , Antibacterianos , Antibioticoprofilaxia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Infecção da Ferida CirúrgicaRESUMO
Cervicofacial infection (CFI) is a common presentation to the Oral and Maxillofacial (OMFS) department and accounts for significant emergency activity. The current study aims to understand the aetiology, management, and clinical features of patients hospitalised with CFI. Our study included all patients admitted for management of CFI from May to October 2017 at 25 OMFS units across 17 UK regions. Data were collected prospectively and included age, comorbidities, prior treatment received, markers of sepsis, and presenting clinical features. One thousand and two (1002) admissions were recorded; 546 (54.5%) were male. Median (range) age was 34 (1-94) years. The most common presenting complaints were trismus (46%) and dysphagia (27%). Airway compromise was present in 1.7% of cases. Odontogenic infection accounted for 822/1002 (82%) admissions. Of those with an infection of odontogenic origin, 453/822 (55.1%) had received previous treatment. Two-thirds of those who had received treatment were managed by antibiotics alone (300/453, 66.2%). Patients met criteria for sepsis in 437/1002 (43.6%) of CFI, and in 374/822 (45.5%) of odontogenic infections. This is the largest study worldwide of patients requiring inpatient management for CFI. Infection due to odontogenic origin is the most frequent reason for admission and nearly half do not seek treatment before presentation. Patients with CFI often present late in their disease and frequently meet criteria for sepsis, requiring timely and aggressive treatment to ensure optimum outcomes. Trismus is an emerging dominant feature with all the implications related to the anaesthetic management of these patients. Knowledge of these factors has implications for the referrer, triage, the emergency department, the anaesthetic team, and members of the OMFS team.
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Serviço Hospitalar de Emergência , Sepse , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Sepse/epidemiologia , TriagemRESUMO
Anammox bacteria that are capable of anaerobically oxidizing ammonium (anammox) with nitrite to nitrogen gas produce unique membrane phospholipids that comprise hydrocarbon chains with three or five linearly condensed cyclobutane rings. To gain insight into the biophysical properties of these 'ladderane' lipids, we have isolated a ladderane phosphatidylcholine and a mixed ladderane phosphatidylethanolamine/phosphatidylglycerol lipid fraction and reconstituted these lipids in different membrane environments. Langmuir monolayer experiments demonstrated that the purified ladderane phospholipids form fluid films with a relatively high lipid packing density. Fluid-like behavior was also observed for ladderane lipids in bilayer systems as monitored by cryo-electron microscopy on large unilamellar vesicles (LUVs) and epi-fluorescence microscopy on giant unilamellar vesicles (GUVs). Analysis of the LUVs by fluorescence depolarization revealed a relatively high acyl chain ordering in the hydrophobic region of the ladderane phospholipids. Micropipette aspiration experiments were applied to study the mechanical properties of ladderane containing lipid bilayers and showed a relatively high apparent area compressibility modulus for ladderane containing GUVs, thereby confirming the fluid and acyl chain ordered characteristics of these lipids. The biophysical findings in this study support the previous postulation that dense membranes in anammox cells protect these microbes against the highly toxic and volatile anammox metabolites.
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Bactérias/química , Membrana Celular/química , Fluidez de Membrana , Lipídeos de Membrana/química , Fosfolipídeos/química , Compostos de Amônio Quaternário/metabolismo , Bactérias/metabolismo , Fenômenos Mecânicos , Lipossomas Unilamelares/químicaRESUMO
INTRODUCTION: Ossification of the pterygospinous and pterygoalar ligaments has been well documented forming pterygospinous and pterygoalar bars. However, the actual ligaments have been rarely shown in the existing literature. Therefore, this study aimed to reveal the anatomy of the pterygoalar ligament/bar and pterygospinous ligament/bar, and its relationship with the branches of the mandibular nerve. METHODS: Thirty sides from fifteen Caucasian fresh frozen cadaveric heads were used in this study. The branches of the mandibular nerve and any ligaments or bony bridges between the lateral plate of the pterygoid process and spine of the sphenoid were observed. RESULTS: A pterygospinous ligament/bar and pterygoalar ligament/bar were defined based on the relationship with the branches of the mandibular nerve. The pterygoalar ligament/bar was further classified into two types. Twenty-seven sides (90%) had at least one pterygoalar ligament/bar or pterygospinous ligament/bar. A pterygospinous ligament/bar was found on 15 sides (50.0%). A pterygoalar ligament/bar was found on 16 sides (53.3%), and a type I on 11 sides and type II on 5 sides. CONCLUSIONS: This finding and classification are simple to understand and easy to apply for future studies, and have important implications regarding the clinical anatomy of trigeminal neuralgia and facial pain.