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1.
Mol Phylogenet Evol ; 161: 107172, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33813020

RESUMO

Larger molecular phylogenies based on ever more genes are becoming commonplace with the advent of cheaper and more streamlined sequencing and bioinformatics pipelines. However, many groups of inconspicuous but no less evolutionarily or ecologically important marine invertebrates are still neglected in the quest for understanding species- and higher-level phylogenetic relationships. Here, we alleviate this issue by presenting the molecular sequences of 165 cheilostome bryozoan species from New Zealand waters. New Zealand is our geographic region of choice as its cheilostome fauna is taxonomically, functionally and ecologically diverse, and better characterized than many other such faunas in the world. Using this most taxonomically broadly-sampled and statistically-supported cheilostome phylogeny comprising 214 species, when including previously published sequences, and 17 genes (2 nuclear and 15 mitochondrial) we tested several existing systematic hypotheses based solely on morphological observations. We find that lower taxonomic level hypotheses (species and genera) are robust while our inferred trees did not reflect current higher-level systematics (family and above), illustrating a general need for the rethinking of current hypotheses. To illustrate the utility of our new phylogeny, we reconstruct the evolutionary history of frontal shields (i.e., a calcified body-wall layer in ascus-bearing cheilostomes) and ask if its presence has any bearing on the diversification rates of cheilostomes.


Assuntos
Evolução Biológica , Briozoários/classificação , Briozoários/genética , Filogenia , Animais , Briozoários/anatomia & histologia , Nova Zelândia
2.
BMC Pediatr ; 18(1): 294, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-30185160

RESUMO

BACKGROUND: Movement and physical activity is crucial to brain development and has a positive impact on the ability to learn. With children spending a large portion of their time in the school setting, physical activity and the development of motor skills in this environment may not only impact their overall development but may also influence their learning. The aim of this study was to investigate relationships between motor proficiency and reading skills in Year-1 children. METHODS: A cross-sectional study with a single class of Year-1 students (n = 24: mean age = 6.07 ± 0.35 years). Assessments included; a) Process Assessment of the Learner (PAL-II) - Diagnostics for Reading and Writing (reading components only); b) Bruininks-Oseretsky-Test-of-Motor-Proficiency (BOT2); c) parent-reported height/weight and; d) Preparatory Year academic reports. The PAL-II was individually administered. The BOT2 was administered in small groups. Parent-reported height and weight measurements as well as Preparatory Year reports provided by the school Principal were obtained for each participant. RESULTS: Significant negative relationships were obtained between Year-1 children's total motor proficiency and silent reading ability (r = -.53 to -.59, p ≤ .01). While not significant for female students, the relationships were significant and strongly correlated for male students (r = -.738 to -.810, p ≤ .001). Children with low-average English grades demonstrated a strong positive relationship between motor proficiency and pre-reading skills, essential to functional reading (r = .664., p = .04 to r = .716, p = .04). CONCLUSION: For children with low-average English grades, the strong, positive relationship between motor proficiency and pre-reading skills suggests that this population may benefit from additional motor proficiency skills. Blending of motor skills within the English curriculum may benefit both of these sub-groups within a classroom environment.


Assuntos
Destreza Motora/fisiologia , Leitura , Criança , Pré-Escolar , Estudos Transversais , Exercício Físico/fisiologia , Feminino , Humanos , Aprendizagem/fisiologia , Masculino , Testes Neuropsicológicos , Fatores Sexuais
3.
J Clean Prod ; 171: 1672-1680, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-29333000

RESUMO

Life Cycle Assessment (LCA) of livestock production systems is often based on inventory data for farms typical of a study region. As information on individual animals is often unavailable, livestock data may already be aggregated at the time of inventory analysis, both across individual animals and across seasons. Even though various computational tools exist to consider the effect of genetic and seasonal variabilities in livestock-originated emissions intensity, the degree to which these methods can address the bias suffered by representative animal approaches is not well-understood. Using detailed on-farm data collected on the North Wyke Farm Platform (NWFP) in Devon, UK, this paper proposes a novel approach of life cycle impact assessment that complements the existing LCA methodology. Field data, such as forage quality and animal performance, were measured at high spatial and temporal resolutions and directly transferred into LCA processes. This approach has enabled derivation of emissions intensity for each individual animal and, by extension, its intra-farm distribution, providing a step towards reducing uncertainty related to agricultural production inherent in LCA studies for food. Depending on pasture management strategies, the total emissions intensity estimated by the proposed method was higher than the equivalent value recalculated using a representative animal approach by 0.9-1.7 kg CO2-eq/kg liveweight gain, or up to 10% of system-wide emissions. This finding suggests that emissions intensity values derived by the latter technique may be underestimated due to insufficient consideration given to poorly performing animals, whose emissions becomes exponentially greater as average daily gain decreases. Strategies to mitigate life-cycle environmental impacts of pasture-based beef productions systems are also discussed.

4.
Eur J Soil Sci ; 67(4): 374-385, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27867310

RESUMO

The North Wyke Farm Platform was established as a United Kingdom national capability for collaborative research, training and knowledge exchange in agro-environmental sciences. Its remit is to research agricultural productivity and ecosystem responses to different management practices for beef and sheep production in lowland grasslands. A system based on permanent pasture was implemented on three 21-ha farmlets to obtain baseline data on hydrology, nutrient cycling and productivity for 2 years. Since then two farmlets have been modified by either (i) planned reseeding with grasses that have been bred for enhanced sugar content or deep-rooting traits or (ii) sowing grass and legume mixtures to reduce nitrogen fertilizer inputs. The quantities of nutrients that enter, cycle within and leave the farmlets were evaluated with data recorded from sensor technologies coupled with more traditional field study methods. We demonstrate the potential of the farm platform approach with a case study in which we investigate the effects of the weather, field topography and farm management activity on surface runoff and associated pollutant or nutrient loss from soil. We have the opportunity to do a full nutrient cycling analysis, taking account of nutrient transformations in soil, and flows to water and losses to air. The NWFP monitoring system is unique in both scale and scope for a managed land-based capability that brings together several technologies that allow the effect of temperate grassland farming systems on soil moisture levels, runoff and associated water quality dynamics to be studied in detail. HIGHLIGHTS: Can meat production systems be developed that are productive yet minimize losses to the environment?The data are from an intensively instrumented capability, which is globally unique and topical.We use sensing technologies and surveys to show the effect of pasture renewal on nutrient losses.Platforms provide evidence of the effect of meteorology, topography and farm activity on nutrient loss.

5.
Int J Sports Med ; 37(7): 552-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27116345

RESUMO

The purpose of this study was to apply a time-motion model to estimate and describe the energy expenditure and metabolic power demands of playing positions in elite rugby league match-play, utilizing Global Positioning System (GPS) devices. 18 elite rugby league players participated in this study. Players' positional groups included: outside backs (n=59 files, n=4 players), adjustables (n=74 files, n=4 players), wide-running (n=104 files, n=7 players) and hit-up forwards (n=36 files, n=3 players). Outside backs expended the greatest total energy (40.1±5.0 kJ·kg(-1)) per match, equivalent to 8.1%, 26.6% and 61.9% greater energy than adjustables, wide-running and hit-up forwards, respectively. Adjustables attained an anaerobic index 7.3% higher than wide-running forwards, 19.7% higher than hit-up forwards (p=0.001) and 43.2% higher than outside backs (p<0.001). Wide-running forwards achieved an anaerobic index (0.34±0.04) 11% and 32.8% higher than hit-up forwards (p=0.001) and outside backs (p<0.001), respectively. Mean power of adjustables (10.0±0.9 W·kg(-1)) was significantly higher than all other groups (outside backs: 28.8%, 7.8±1.0; hit-up: 12.4%, 8.9±0.6; and wide-running: 8.7%, 9.2±0.7 forwards) (p<0.001). Energetics indices indicated differing metabolic demands for all positional groups, suggesting position-specific conditioning drills are required to replicate the energetic demands of match-play.


Assuntos
Desempenho Atlético/fisiologia , Metabolismo Energético , Futebol Americano/fisiologia , Adulto , Fenômenos Biomecânicos , Sistemas de Informação Geográfica , Humanos , Masculino , Consumo de Oxigênio , Adulto Jovem
6.
AJR Am J Roentgenol ; 205(5): 1114-20, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26496560

RESUMO

OBJECTIVE: The objective of our study was to determine the adverse reaction rate associated with the administration of blood pool contrast material in children and young adults. MATERIALS AND METHODS: A review of the MRI and pharmacy databases identified all patients who received gadofosveset trisodium from October 1, 2011, to June 30, 2014. Patients were classified as having been anesthetized or not anesthetized for the MRI examinations. A review of the electronic medical records identified adverse reactions recorded within 24 hours of contrast administration. The adverse reactions were graded as mild, moderate, or severe. Risk ratios were calculated between the adverse reaction rate experienced by anesthetized patients and that experience by nonanesthetized patients. RESULTS: During the study period, 626 patients (mean age, 11.7 years) received 711 doses of gadofosveset trisodium; 137 adverse reactions were recorded, which yields a 19.3% (137/711) adverse reaction rate. There were 115 adverse reactions experienced by 367 anesthetized patients (31.3%): 93.0% (107/115) were mild and 7.0% (8/115) were moderate. The remaining 22 adverse reactions were experienced by 344 (6.4%) nonanesthetized patients, and 90.9% (20/22) were mild. Three nonanesthetized patients had allergiclike reactions; of these allergiclike reactions, one was mild and two were severe for a severe allergiclike reaction rate of 0.28% (2/711). Severe allergiclike reactions were treated without any adverse outcomes. Anesthetized patients were 5.7 times more likely to experience an adverse event than nonanesthetized patients; most reactions in anesthetized patients were seen after the administration of anesthesia alone. CONCLUSION: Most reactions after gadofosveset trisodium administration in children and young adults are mild; however, severe allergiclike reactions occur, so policies must be in place to treat patients with adverse reactions when using this contrast agent. These data may be useful to centers considering administering gadofosveset trisodium to pediatric patients.


Assuntos
Meios de Contraste/efeitos adversos , Gadolínio/efeitos adversos , Imageamento por Ressonância Magnética , Compostos Organometálicos/efeitos adversos , Adolescente , Sistemas de Notificação de Reações Adversas a Medicamentos , Criança , Pré-Escolar , Meios de Contraste/administração & dosagem , Feminino , Gadolínio/administração & dosagem , Humanos , Lactente , Recém-Nascido , Masculino , Compostos Organometálicos/administração & dosagem , Estudos Retrospectivos , Segurança , Adulto Jovem
7.
Spine J ; 24(6): 989-1000, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38199449

RESUMO

Spondylolisthesis is a common finding in middle-aged and older adults with back pain. The pathophysiology of degenerative spondylolisthesis is a subject of controversy regarding not only its etiology but also the mechanisms of its progression. It is theorized that degeneration of the facets and discs can lead to segmental instability, leading to displacement over time. Kirkaldy-Willis divided degenerative spondylolisthesis into three phases: dysfunction, instability, and finally, restabilization. There is a paucity of literature on the unification of the radiological hallmarks seen in spondylolisthesis within these phases. The radiographic features include (1) facet morphology/arthropathy, (2) facet effusion, (3) facet vacuum, (4) synovial cyst, (5) interspinous ligament bursitis, and (6) vacuum disc as markers of dysfunction, instability, and/or restabilization. We discuss these features, which can be seen on X-ray, CT, and MRI, with the intention of establishing a timeline upon which they present clinically. Spondylolisthesis is initiated as either degeneration of the intervertebral disc or facet joints. Early degeneration can be seen as facet vacuum without considerable arthropathy. As the vertebral segment becomes increasingly dynamic, fluid accumulates within the facet joint space. Further degeneration will lead to the advancement of facet arthropathy, degenerative disc disease, and posterior ligamentous complex pathology. Facet effusion can eventually be replaced with a vacuum in severe facet osteoarthritis. Intervertebral disc vacuum continues to accumulate with further cleft formation and degeneration. Ultimately, autofusion of the vertebra at the facets and endplates can be observed. With this review, we hope to increase awareness of these radiographical markers and their timeline, thus placing them within the framework of the currently accepted model of degenerative spondylolisthesis, to help guide future research and to help refine management guidelines.


Assuntos
Vértebras Lombares , Espondilolistese , Espondilolistese/diagnóstico por imagem , Humanos , Vértebras Lombares/diagnóstico por imagem , Radiografia , Progressão da Doença , Degeneração do Disco Intervertebral/diagnóstico por imagem
8.
J Neurosurg Spine ; 38(1): 115-125, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36152329

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the safety and efficacy of a posterior facet replacement device, the Total Posterior Spine (TOPS) System, for the treatment of one-level symptomatic lumbar stenosis with grade I degenerative spondylolisthesis. Posterior lumbar arthroplasty with facet replacement is a motion-preserving alternative to lumbar decompression and fusion. The authors report the preliminary results from the TOPS FDA investigational device exemption (IDE) trial. METHODS: The study was a prospective, randomized controlled FDA IDE trial comparing the investigational TOPS device with transforaminal lumbar interbody fusion (TLIF) and pedicle screw fixation. The minimum follow-up duration was 24 months. Validated patient-reported outcome measures included the Oswestry Disability Index (ODI) and visual analog scale (VAS) for back and leg pain. The primary outcome was a composite measure of clinical success: 1) no reoperations, 2) no device breakage, 3) ODI reduction of ≥ 15 points, and 4) no new or worsening neurological deficit. Patients were considered a clinical success only if they met all four measures. Radiographic assessments were made by an independent core laboratory. RESULTS: A total of 249 patients were evaluated (n = 170 in the TOPS group and n = 79 in the TLIF group). There were no statistically significant differences between implanted levels (L4-5: TOPS, 95% and TLIF, 95%) or blood loss. The overall composite measure for clinical success was statistically significantly higher in the TOPS group (85%) compared with the TLIF group (64%) (p = 0.0138). The percentage of patients reporting a minimum 15-point improvement in ODI showed a statistically significant difference (p = 0.037) favoring TOPS (93%) over TLIF (81%). There was no statistically significant difference between groups in the percentage of patients reporting a minimum 20-point improvement on VAS back pain (TOPS, 87%; TLIF, 64%) and leg pain (TOPS, 90%; TLIF, 88%) scores. The rate of surgical reintervention for facet replacement in the TOPS group (5.9%) was lower than the TLIF group (8.8%). The TOPS cohort demonstrated maintenance of flexion/extension range of motion from preoperatively (3.85°) to 24 months (3.86°). CONCLUSIONS: This study demonstrates that posterior lumbar decompression and dynamic stabilization with the TOPS device is safe and efficacious in the treatment of lumbar stenosis with degenerative spondylolisthesis. Additionally, decompression and dynamic stabilization with the TOPS device maintains segmental motion.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Espondilolistese , Humanos , Espondilolistese/diagnóstico por imagem , Espondilolistese/cirurgia , Fusão Vertebral/métodos , Resultado do Tratamento , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Estudos Prospectivos , Constrição Patológica/cirurgia , Dor nas Costas/cirurgia , Artroplastia , Procedimentos Cirúrgicos Minimamente Invasivos , Estudos Retrospectivos
9.
World Neurosurg ; 159: e399-e406, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34954442

RESUMO

OBJECTIVE: To determine whether the L3-L4 disc angle may be a surrogate marker for global lumbar alignment in thoracolumbar fusion surgery and to explore the relationship between radiographic and patient-reported outcomes after thoracolumbar fusion surgery. METHODS: Retrospective chart review was conducted on patients who had undergone a lumbar fusion involving levels from T9 to pelvis. EuroQol-Five Dimension (EQ-5D-3L) scores and adverse events including adjacent-segment disease and degeneration, pseudoarthrosis, proximal junctional kyphosis, stenosis, and reoperation were collected. Pre- and postoperative spinopelvic parameters were measured on weight-bearing radiographs, with the L3-L4 disc angle of novel interest. Univariate logistic and linear regression were performed to assess the associations of radiographic parameters with adverse event incidence and improvement in EQ-5D-3L, respectively. RESULTS: In total, 182 patients met inclusion criteria. Univariable analysis revealed that increased magnitude of L3-L4 disc angle, anterior pelvic tilt, and pelvic incidence measures are associated with increased likelihood of developing postoperative adverse events. Conversely, increased lumbar lordosis demonstrated a decreased incidence of developing a postoperative adverse event. Linear regression showed that radiographic parameters did not significantly correlate with postoperative EQ-5D-3L scores, although scores were significantly improved postfusion in all dimensions except Self-Care (P = 0.51). CONCLUSIONS: L3-L4 disc angle magnitude may serve as a surrogate marker of global lumbar alignment. The degree of spinopelvic alignment did not correlate to improvement in EQ-5D-3L score in the present study, suggesting that quality of life metric change may not be a sensitive or specific marker of postfusion alignment.


Assuntos
Lordose , Fusão Vertebral , Humanos , Lordose/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Qualidade de Vida , Estudos Retrospectivos , Fusão Vertebral/métodos
10.
J Sci Med Sport ; 23(8): 735-739, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31926869

RESUMO

OBJECTIVES: This study evaluated the benefit of physically-active lessons for learning maths multiplication-tables. The impact of the intervention on general numeracy, physical activity (PA), aerobic fitness, body mass index (BMI) and school-day moderate to vigorous PA (MVPA) was also assessed. DESIGN: Randomised controlled cross-over trial. METHOD: Year 3 students (n=172, mean age 8.4±0.3 years, 48% male) were recruited from 10 classes across two urban primary schools. Participants were randomly assigned to a seated classroom (Classroom) group or physically-active lessons in the playground (Playground) and crossed over to the alternative condition in the subsequent school term. The 6-week intervention comprised 3×30min sessions/week. Multiplication-tables (teacher-designed test) and general maths (standardised test) were assessed pre- and post-intervention. Aerobic fitness was assessed via the shuttle-run. Pre- to post-intervention change scores were compared for analysis and effect sizes (ES) calculated. Total PA and MVPA were assessed with accelerometers in a subset of participants. RESULTS: Multiplication scores improved significantly more in Playground than Classroom groups (ES=0.23; p=0.045), while no significant differences were observed in general numeracy (ES=0.05; p=0.66). Total PA and MVPA were substantially higher during Playground than Classroom lessons (ES: total PA=7.4, MVPA=6.5; p<0.001) but there were no differences in PA/MVPA between the groups throughout the rest of the school day. Aerobic fitness improved more in Playground than Classroom groups (ES=0.3; p<0.001) while the change in BMI was not different between groups (p=0.39). CONCLUSIONS: Physically-active lessons may benefit the learning of maths multiplication-tables while favourably contributing to school-day PA/MVPA.


Assuntos
Exercício Físico , Aprendizagem , Matemática/educação , Modelos Educacionais , Actigrafia , Índice de Massa Corporal , Criança , Estudos Cross-Over , Feminino , Humanos , Masculino , Instituições Acadêmicas
11.
Ann Occup Environ Med ; 30: 15, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29507731

RESUMO

BACKGROUND: The nature of police work often necessitates use of Individual Light Armour Vests (ILAVs) for officer protection. Previous research has demonstrated various biomechanical and physical performance impacts of ILAVs, however, little knowledge exists on the individual officer's perceptions of ILAV. The aim of this study was to investigate officers' perceptions of the impacts of three different ILAVs and normal station wear whilst performing police occupational tasks. METHODS: A prospective, within subjects, repeated measures design was employed in which 11 serving police officers wore each of three different types of body armour (ILAV A, ILAV B or ILAV C) and normal station wear for a full day while performing tasks including a simulated victim drag, a patrol vehicle exit and a marksmanship shoot. Ratings of Perceived Exertion (RPE) and a Visual Analogue Scale (VAS; - 10 to + 10) were used to examine officer perceptions of each ILAV. Finally, officers were asked to indicate areas of both discomfort and comfort of each ILAV on a mannequin chart. RESULTS: Officers perceived less effort was required for the victim drag whilst wearing ILAV B (RPE = 3.6/10) when compared to ILAV A, ILAV C and even station wear (RPE = 4.7/10, 4.0/10, 3.8/10, respectively). A positive impact on performance was perceived for ILAV B (VAS = + 0.26) when performing a patrol vehicle exit and sprint task but not for the other two ILAVs (VAS = - 3.58, - 0.55, - 0.85, respectively). Officers perceived a positive impact of ILAV B (VAS = + 2.7) and station wear (VAS = + 1.4) and a negative impact of ILAVs A and C (VAS = - 2.1, - 1.7 respectively) on marksmanship. Despite all armour types being criticized for discomfort, ILAV B received lower ratings of discomfort overall, and some positive comments regarding both comfort and performance. CONCLUSIONS: Officers perceived ILAV B to have positive effects on task performance. It was also rated more comfortable than the other two, possibly due to a longer torso design which shifted load from the shoulders to the hips and pelvis. Officer perceptions of comfort and effects on occupational performance should be considered when designing and procuring armour systems. Although ILAVs may be similar, perceived impacts may vary between officers.

12.
Data Brief ; 17: 570-574, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29552605

RESUMO

With increasing concern about environmental burdens originating from livestock production, the importance of farming system evaluation has never been greater. In order to form a basis for trade-off analysis of pasture-based cattle production systems, liveweight data from 90 Charolais × Hereford-Friesian calves were collected at a high temporal resolution at the North Wyke Farm Platform (NWFP) in Devon, UK. These data were then applied to the Intergovernmental Panel on Climate Change (IPCC) modelling framework to estimate on-farm methane emissions under three different pasture management strategies, completing a foreground dataset required to calculate emissions intensity of individual beef cattle.

13.
Spine J ; 18(6): 1014-1021, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29174460

RESUMO

BACKGROUND CONTEXT: Patients with spinal deformity may present with complaints related to either the deformity itself or the manifestations of the coexisting spinal stenosis. There are reports of successful management of lumbar pathology in the absence of global sagittal or coronal imbalance, with limited decompression and fusion, addressing only the symptomatic segment. PURPOSE: Our study examined the long-term outcomes of transforaminal lumbar interbody fusion (TLIF), a less extensive procedure, based on the experience of the senior author over the past 10 years. STUDY DESIGN/SETTING: This was a retrospective study of symptomatic lumbar spinal stenosis and spinal deformity managed by one surgeon at The Cleveland Clinic since 2003. PATIENT SAMPLE: Forty-one patients were included in the study. OUTCOME MEASURES: The present study measures the long-term clinical functional outcomes of these patients through EQ-5D (EuroQol five dimensions questionnaire), PHQ-9 (Patient Health Questionnaire), and PDQ (Pain Disability Questionnaire) forms, along with documented radiographic parameters and Charlson Comorbidity Index (CCI). METHODS: There were no funding or potential conflicts of interest associated biases in the present study. Patients with symptomatic lumbar spinal stenosis with neutral global alignment in the sagittal and coronal planes and symptomatic stenosis at the deformity level were treated by limited fusion and TLIF, and had a follow-up period of at least 5 years. Excluded were patients under 18 years of age, had more than three levels of fusion, and had an active spinal malignancy or recent spinal trauma. The grouping variables were curve magnitude, revision surgeries, and TLIF levels. Clinical outcomes were compared in all the grouping variables. Analysis of variance (ANOVA) and chi-square tests were utilized; p<.05 was considered statistically significant. RESULTS: The average age and follow-up period were 66±10 and 7.5 years, respectively. There was no statistical difference between patients with curves measuring between 10° and 20° and greater than 20° for EQ-5D, PHQ-9, and PDQ. Patients had worse PDQ data with larger curves compared with smaller curves at both 5 years and final follow-up. Although there was no statistical significance between preoperative coronal curve magnitude and revision surgeries, patients with curves greater than 20° had higher rates of revision surgeries (75%; p=.343) in the global lumbar curve deformity group. Although there was no statistical significance for patients who underwent revision surgeries,those patients had low PHQ-9 values at the final follow-up (p=.09). The revision surgery rate was 48% in one-level TLIF and 18% in two-level TLIF. Moderate pain disability scores were noticed for one-level TLIF patients (mean=75) compared with two-level TLIF patients (mean=27) at the final follow-up, and approached statistical significance in this comparison (p=.06). CONCLUSION: Although this topic has a limited audience to spinal deformity surgeons, the prevalence of patients who present with adult spinal deformities has been increasing. Short segment fusion, in the setting of modest spinal deformity, is a reasonable and safe option. Further study on the concept of short segment fusions in the growing patient population is required as more comprehensive fusions do have noted complication rates, and a compromise must be reached between the extent of surgery that is enough to provide pain relief and disability and the degree of surgery that is too much to be tolerated in terms of complication rates.


Assuntos
Vértebras Lombares/cirurgia , Escoliose/cirurgia , Fusão Vertebral/métodos , Estenose Espinal/cirurgia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Escoliose/complicações , Estenose Espinal/complicações , Inquéritos e Questionários , Resultado do Tratamento
14.
Spine J ; 18(10): 1727-1732, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29410308

RESUMO

BACKGROUND CONTEXT: Relative value units (RVUs) are a compensation model based on the effort required to provide a procedure or service to a patient. Thus, procedures that are more complex and require greater technical skill and aftercare, such as multilevel spine surgery, should provide greater physician compensation. However, there are limited data comparing RVUs with operative time. Therefore, this study aims to compare mean (1) operative times; (2) RVUs; and (3) RVU/min between posterior segmental instrumentation of 3-6, 7-12, and ≥13 vertebral segments, and to perform annual cost difference analysis. METHODS: A total of 437 patients who underwent instrumentation of 3-6 segments (Cohort 1, current procedural terminology [CPT] code: 22842), 67 patients who had instrumentation of 7-12 segments (Cohort 2, CPT code: 22843), and 16 patients who had instrumentation of ≥13 segments (Cohort 3, CPT code: 22844) were identified from the National Surgical Quality Improvement Program (NSQIP) database. Mean operative times, RVUs, and RVU/min, as well as an annualized cost difference analysis, were calculated and compared using Student t test. This study received no funding from any party or entity. RESULTS: Cohort 1 had shorter mean operative times than Cohorts 2 and 3 (217 minutes vs. 325 minutes vs. 426 minutes, p<.05). Cohort 1 had a lower mean RVU than Cohorts 2 and 3 (12.6 vs. 13.4 vs. 16.4). Cohort 1 had a greater RVU/min than Cohorts 2 and 3 (0.08 vs. 0.05, p<.05; vs. 0.08 vs. 0.05, p>.05). A $112,432.12 annualized cost difference between Cohorts 1 and 2, a $176,744.76 difference between Cohorts 1 and 3, and a $64,312.55 difference between Cohorts 2 and 3 were calculated. CONCLUSION: The RVU/min takes into account not just the value provided but also the operative times required for highly complex cases. The RVU/min for fewer vertebral level instrumentation being greater (0.08 vs. 0.05), as well as the $177,000 annualized cost difference, indicates that compensation is not proportional to the added time, effort, and skill for more complex cases.


Assuntos
Duração da Cirurgia , Procedimentos Ortopédicos/economia , Escalas de Valor Relativo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Custos e Análise de Custo , Current Procedural Terminology , Bases de Dados Factuais , Feminino , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos/estatística & dados numéricos , Melhoria de Qualidade , Estudos Retrospectivos , Coluna Vertebral/cirurgia , Adulto Jovem
15.
Animal ; : 1-11, 2018 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-29650058

RESUMO

For livestock production systems to play a positive role in global food security, the balance between their benefits and disbenefits to society must be appropriately managed. Based on the evidence provided by field-scale randomised controlled trials around the world, this debate has traditionally centred on the concept of economic-environmental trade-offs, of which existence is theoretically assured when resource allocation is perfect on the farm. Recent research conducted on commercial farms indicates, however, that the economic-environmental nexus is not nearly as straightforward in the real world, with environmental performances of enterprises often positively correlated with their economic profitability. Using high-resolution primary data from the North Wyke Farm Platform, an intensively instrumented farm-scale ruminant research facility located in southwest United Kingdom, this paper proposes a novel, information-driven approach to carry out comprehensive assessments of economic-environmental trade-offs inherent within pasture-based cattle and sheep production systems. The results of a data-mining exercise suggest that a potentially systematic interaction exists between 'soil health', ecological surroundings and livestock grazing, whereby a higher level of soil organic carbon (SOC) stock is associated with a better animal performance and less nutrient losses into watercourses, and a higher stocking density with greater botanical diversity and elevated SOC. We contend that a combination of farming system-wide trials and environmental instrumentation provides an ideal setting for enrolling scientifically sound and biologically informative metrics for agricultural sustainability, through which agricultural producers could obtain guidance to manage soils, water, pasture and livestock in an economically and environmentally acceptable manner. Priority areas for future farm-scale research to ensure long-term sustainability are also discussed.

16.
Sleep ; 29(5): 619-23, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16774151

RESUMO

STUDY OBJECTIVES: The depressive effects of hypoxia on the central nervous system are well known. The purpose of this study was to determine the influence of mild overnight hypoxia on the ability of healthy individuals to arouse from non-rapid-eye-movement (NREM) sleep to auditory tones. DESIGN: Randomized cross-over. SETTING: Participants slept in a sound-insulated room with the physiologic recordings and experimental interventions controlled from a separate room. PARTICIPANTS: Eleven healthy men aged 18 to 24 years. INTERVENTIONS: On separate nights, participants were exposed to mild overnight hypoxia (SaO2 approximately 90%) or medical air in single-blind fashion. During established sleep, subjects were administered 1 of 10 auditory tones (500 Hz, 54-90 dB, 5 seconds duration) via earphones, or a sham tone (recording period with no tone). MEASUREMENTS AND RESULTS: The probability and intensity of arousal responses in the 30 seconds following tones or shams were compared between gas conditions and between stage 2 and slow-wave sleep. Arousal probability and intensity increased with tone intensity and were significantly lower during slow-wave compared with stage 2 sleep but were not different between hypoxia and normoxia nights. CONCLUSION: These data suggest that mild overnight hypoxia does not impair the neural mechanisms involved in arousal from sleep to auditory stimuli.


Assuntos
Percepção Auditiva/fisiologia , Hipóxia/sangue , Hipóxia/fisiopatologia , Fases do Sono/fisiologia , Adolescente , Adulto , Dióxido de Carbono/metabolismo , Estudos Cross-Over , Feminino , Humanos , Masculino , Oxigênio/metabolismo , Índice de Gravidade de Doença , Método Simples-Cego , Sono/fisiologia , Fatores de Tempo
17.
J Natl Cancer Inst ; 87(4): 299-303, 1995 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-7707421

RESUMO

BACKGROUND: The folate receptor is a 38 to 39 kd glycoprotein attached to the cell membrane via a glycosylphosphatidylinositol anchor. It serves as the initiation point for receptor-coupled transport of folate in a process known as potocytosis. The receptor is overproduced by a number of malignant cell lines in vitro and in a large percentage of ovarian and uterine malignancies. Immunohistochemistry has shown the receptor to be expressed primarily in normal differentiated tissues such as choroid plexus, placenta, thyroid, and kidney. The receptor gene(s) has been mapped to the human chromosomal locus 11q13. PURPOSE: In order to better understand regulation of the synthesis of the receptor, we studied the expression and accumulation of the folate receptor in UMSCC 38 cells, a human malignant squamous cell carcinoma line with a karyotype that is amplified at the folate receptor gene locus. METHODS: Western blot analysis of octylglucoside-solubilized cell membranes was used to analyze expression of several proteins by UMSCC 38 cells grown in culture under varied conditions. Bands on autoradiographs, representing electrophoresed proteins detected by indirect antibody labeling and an enhanced chemiluminescence reaction, were quantitated by densitometry. RESULTS: The expression of the folate receptor was found to increase approximately fourfold as UMSCC 38 cells were grown to higher cell densities over increasing lengths of time, ranging from 3 to 9 days, in culture. The expression of K1 keratin protein, a known marker of differentiation in squamous cell carcinomas, was elevated to a similar degree (3.2-fold) between day 5 and day 9 in cultures of these cells. Expression of folate-receptor protein in UMSCC 38 cells was also found to be reduced approximately 10-fold when cells were exposed to 1 microM retinoic acid for 48 hours and increased approximately eightfold after a 5-day exposure to 3 microM hydrocortisone. CONCLUSIONS: We present evidence that synthesis of the folate receptor in UMSCC 38 cells is affected by the same pathway that changes the expression of some markers of differentiation in squamous cell carcinomas. IMPLICATIONS: The fact that folate receptor expression in these malignant cells can be manipulated using retinoids and steroids suggests that these hormones could modulate the efficiency of folate and antifolate uptake via the folate receptor and may enhance the usefulness of the receptor as a target for immunotherapy.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Proteínas de Transporte/metabolismo , Ácido Fólico/metabolismo , Regulação Neoplásica da Expressão Gênica , Receptores de Superfície Celular , Antígenos de Diferenciação/metabolismo , Northern Blotting , Carcinoma de Células Escamosas/patologia , Proteínas de Transporte/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Receptores de Folato com Âncoras de GPI , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Hidrocortisona/farmacologia , Tretinoína/farmacologia , Células Tumorais Cultivadas
18.
Cancer Res ; 55(4): 847-52, 1995 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-7850798

RESUMO

UM-SCC-38 cells, a squamous cell carcinoma cell line of the head and neck, express limited amounts of folate receptor alpha antigen which is not capable of binding either folic acid or 5-methyltetrahydrofolic acid. Three distinct mutations in the open reading frame of the folate receptor were identified. We now show that the three mutants are nonfunctional with respect to folic acid binding because the protein products do not bind folate. Additionally, a study of MA104 cells (a receptor-positive cell line) transfected with each mutant was done. Expression of one mutant, FR-67, results in a dominant negative phenotype because folate binding is significantly reduced although membrane antigen is significantly increased. Coexpression of FR-67 and the normal protein in MA104 cells also results in large, bright clusters of receptor protein inside the cell around the nucleus when visualized using indirect immunofluorescence. These clusters are not found in cells that express either normal or FR-67 protein alone. In conclusion, this study provides the first evidence of a mutant folate receptor protein capable of affecting normal receptor function in a dominant negative manner.


Assuntos
Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Fenótipo , Mutação Puntual , Receptores de Superfície Celular , Animais , Células CHO/fisiologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/ultraestrutura , Proteínas de Transporte/biossíntese , Cricetinae , DNA Complementar/genética , Receptores de Folato com Âncoras de GPI , Ácido Fólico/metabolismo , Genes Dominantes , Glicosilfosfatidilinositóis/metabolismo , Haplorrinos , Humanos , Tetra-Hidrofolatos/metabolismo , Transfecção , Trítio
19.
Cancer Res ; 54(14): 3905-11, 1994 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-8033114

RESUMO

Some cells accumulate folate via a receptor-coupled process termed potocytosis. The folate receptor, a glycosyl phosphatidylinositol anchored M(r) 38,000-39,000 glycoprotein, is coded for by at least two genes (FR alpha and FR beta) at 11q13. The karyotype of UMSCC38, a human squamous cell carcinoma cell line, suggests that it may contain multiple copies of the folate receptor gene(s). Southern blot analysis confirms the presence of four to six copies. Using polymerase chain reaction methodology, Northern blot analysis, immunoblotting, and immunofluorescence, we find relatively limited expression of FR alpha and no FR beta in UMSCC38 cells when compared to nonamplified lines. Antigen is observed on the cell surface in a punctate pattern, and the protein is anchored via a glycosyl phosphatidylinositol anchor. Transport of 5-[methyl-3H]tetrahydrofolic acid is blocked by 5-methyltetrahydrofolic acid and probenecid, which suggests anion transport. Monensin, an inhibitor of potocytosis, and folic acid, a high-affinity ligand for the receptor, do not effectively block 5-methyltetrahydrofolic acid transport. Taken together, the results suggest that UMCSCC38 cells, although gene amplified, synthesize surprisingly small amounts of receptor and that receptor is nonfunctional. In order to establish further the nature of the receptor, 16 clones were obtained, and the complementary DNA was sequenced. Three mutations were found.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Proteínas de Transporte/biossíntese , Cromossomos Humanos Par 11 , Amplificação de Genes , Receptores de Superfície Celular , Sequência de Bases , Transporte Biológico , Carcinoma de Células Escamosas/genética , Proteínas de Transporte/análise , Proteínas de Transporte/genética , DNA Complementar/química , Receptores de Folato com Âncoras de GPI , Ácido Fólico/metabolismo , Humanos , Dados de Sequência Molecular , Mutação , Tetra-Hidrofolatos/metabolismo , Células Tumorais Cultivadas
20.
Spine (Phila Pa 1976) ; 41(17): E1039-E1045, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26926356

RESUMO

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: The objective of this study is to compare the radiographic and clinical outcomes of transforaminal lumbar interbody fusion (TLIF) with bilateral facetectomy (BF) versus unilateral facetectomy (UF). SUMMARY OF BACKGROUND DATA: BF is a surgical technique utilized with the intent of creating a greater degree of segmental lordosis than UF alone. However, the clinical benefits of this technique have not been defined. We seek to determine whether a difference exists between bilateral versus UF during TLIF by utilizing both clinical and radiographic outcome measures. METHODS: The electronic medical records of 57 patients who underwent single-level TLIF with either a UF (n = 28) or BF (n = 29) were reviewed. Clinical outcomes were measured through Patient Health Questionnaire-9 (PHQ-9), Pain Disability Questionnaire (PDQ), EuroQol 5 Dimensions (EQ-5D) Health State, and Quality Adjusted Life Year (QALY). Radiographic parameters including disc height and sagittal balance were measured on plain radiographs at 1 year following operation. RESULTS: All radiographic parameters showed no significant differences between the UF and BF cohorts. Segmental lordosis increased significantly in both cohorts. However, there was no significant difference in the increase of segmental lordosis between cohorts. Overall lumbar lordosis did not increase significantly in either cohort. Perioperative complications were also similar between cohorts. PDQ and EQ-5D scores improved significantly in both cohorts at 1 year postoperatively. The BF cohort showed a significantly greater improvement in both EQ-5D (0.1 ±â€Š0.2 vs. 0.3 ±â€Š0.2, P = 0.01) and PHQ-9 scores (-0.8 ±â€Š4.6 vs. 4.6 ±â€Š5.2, P = 0.03) than the UF cohort. The PDQ score improved over the minimally clinical important difference (MCID) of 26 in only the BF cohort. CONCLUSION: The findings in the present study demonstrate that BF during single-level TLIF improves clinical outcomes to a greater degree than UF without any notable differences in perioperative complications or radiographic measurements. LEVEL OF EVIDENCE: 3.


Assuntos
Lordose/etiologia , Vértebras Lombares/cirurgia , Região Lombossacral/cirurgia , Fusão Vertebral , Espondilolistese/cirurgia , Articulação Zigapofisária/cirurgia , Adulto , Idoso , Avaliação da Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Estudos Retrospectivos , Fusão Vertebral/métodos , Resultado do Tratamento , Adulto Jovem
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