Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.579
Filtrar
1.
Rev Sci Instrum ; 94(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38085053

RESUMO

For most laboratory plasma experiments, Coulomb collisions between the particle species are sufficiently frequent that the particle distribution functions are relaxed to a near-Maxwellian form. This hampers the applicability of such experiments to phenomena observed in tenuous and near-collisionless space plasma. The Terrestrial Reconnection EXperiment (TREX) at the Wisconsin Plasma Physics Laboratory aims to study collisionless reconnection for parameters relevant to the Earth's magnetosphere. To reduce the role of collisional effects, a reconnection Drive Cylinder has been developed, which increases both the effective system size of the TREX configuration and the rate at which reconnection can be driven. These two effects now permit TREX to reach a kinetic reconnection regime where collisional effects are minimized. The Drive Cylinder is comprised of 12 single loop drive-coils connected in parallel to a 10 kV capacitor bank. Insulated sheets of aluminum are applied to smooth the magnetic fields and enhance the drive efficiency. Following is a description of the technical details and performance of the Drive Cylinder.

2.
Oper Dent ; 48(5): 546-551, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37415337

RESUMO

BACKGROUND: The open sandwich technique is a reliable alternative to amalgam placement in deep proximal box preparations, where proper isolation and enamel bonding may not be possible. It is often difficult to prepare the box for composite placement without affecting the resin-modified glass ionomer (RMGI) that has been placed in the gingival portion. We hypothesized that RMGI surfaces that are roughened or those that use all steps in the manufacturing bonding protocol, including the priming solution, applied before placing a bonded composite increment, would have greater composite/RMGI shear bond strength. DESIGN AND METHODS: Shear bond strengths (SBS) of RMGI tested in the presence and absence of SiC roughening and primer-coating were tested using a fourth-generation dentin bonding agent to composite after thermocycling. Twenty specimens for four test conditions were fabricated and investigated. Data were subjected to a two-way ANOVA and the Holm-Sidak post-hoc test. RESULTS: Placing dentin primer on unabraded RMGI provided a statistically significant improvement in SBS, but only modestly. Furthermore, because bond failure consistently occurred within the RMGI itself, none of the surface modifications have a clinically relevant impact on SBS at the RMGI to the composite interface. CONCLUSIONS: Clinicians should be aware that they need not avoid RMGI abrasion and do not need to incorporate all components of a fourth-generation bonding system when covering an RMGI sandwich layer with composite.


Assuntos
Colagem Dentária , Colagem Dentária/métodos , Resinas Compostas/química , Dióxido de Silício/química , Dentina , Teste de Materiais , Resistência ao Cisalhamento , Cimentos de Resina/química , Propriedades de Superfície , Adesivos Dentinários/química
3.
Symbiosis ; : 1-14, 2023 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-37360551

RESUMO

Despite the current decline of scleractinian coral populations, octocorals are thriving on reefs in the Caribbean Sea and western North Atlantic Ocean. These cnidarians are holobiont entities, interacting with a diverse array of microorganisms. Few studies have investigated the spatial and temporal stability of the bacterial communities associated with octocoral species and information regarding the co-occurrence and potential interactions between specific members of these bacterial communities remain sparse. To address this knowledge gap, this study investigated the stability of the bacterial assemblages associated with two common Caribbean octocoral species, Eunicea flexuosa and Antillogorgia americana, across time and geographical locations and performed network analyses to investigate potential bacterial interactions. Results demonstrated that general inferences regarding the spatial and temporal stability of octocoral-associated bacterial communities should not be made, as host-specific characteristics may influence these factors. In addition, network analyses revealed differences in the complexity of the interactions between bacteria among the octocoral species analyzed, while highlighting the presence of genera known to produce bioactive secondary metabolites in both octocorals that may play fundamental roles in structuring the octocoral-associated bacteriome. Supplementary Information: The online version contains supplementary material available at 10.1007/s13199-023-00923-x.

4.
ESMO Open ; 8(4): 101589, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37385154

RESUMO

BACKGROUND: Sasanlimab is an antibody to the programmed cell death protein 1 receptor. We report updated data of subcutaneous sasanlimab in non-small-cell lung cancer (NSCLC) and urothelial carcinoma dose expansion cohorts from a first-in-human phase Ib/II study. PATIENTS AND METHODS: Patients were ≥18 years of age with NSCLC or urothelial carcinoma, and no prior immunotherapies, who progressed on or were intolerant to systemic therapy, or for whom systemic therapy was refused or unavailable. Patients received subcutaneous sasanlimab at 300 mg every 4 weeks (q4w). Primary objectives were to evaluate safety, tolerability, and clinical efficacy by objective response rate (ORR). RESULTS: Sixty-eight and 38 patients with NSCLC and urothelial carcinoma, respectively, received subcutaneous sasanlimab. Overall, sasanlimab was well tolerated; 13.2% of patients experienced grade ≥3 treatment-related adverse events. Confirmed ORR was 16.4% and 18.4% in the NSCLC and urothelial carcinoma cohorts, respectively. ORR was generally higher in patients with high programmed death-ligand 1 (PD-L1) expression (≥25%) and high tumor mutational burden (TMB; >75%). In the NSCLC and urothelial carcinoma cohorts, median progression-free survival (PFS) was 3.7 and 2.9 months, respectively; corresponding median overall survival (OS) was 14.7 and 10.9 months. Overall, longer median PFS and OS correlated with high PD-L1 expression and high TMB. Longer median PFS and OS were also associated with T-cell inflamed gene signature in the urothelial carcinoma cohort. CONCLUSIONS: Subcutaneous sasanlimab at 300 mg q4w was well tolerated with promising clinical efficacy observed. Phase II and III clinical trials of sasanlimab are ongoing to validate clinical benefit. Subcutaneous sasanlimab may be a potential treatment option for patients with NSCLC or urothelial carcinoma.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células de Transição , Neoplasias Pulmonares , Neoplasias da Bexiga Urinária , Humanos , Antígeno B7-H1 , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma de Células de Transição/tratamento farmacológico , Inibidores de Checkpoint Imunológico/efeitos adversos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias da Bexiga Urinária/tratamento farmacológico , Adolescente , Adulto
5.
Genome Res ; 32(7): 1242-1253, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35710300

RESUMO

Structural variants (SVs) can affect protein-coding sequences as well as gene regulatory elements. However, SVs disrupting protein-coding sequences that also function as cis-regulatory elements remain largely uncharacterized. Here, we show that craniosynostosis patients with SVs containing the histone deacetylase 9 (HDAC9) protein-coding sequence are associated with disruption of TWIST1 regulatory elements that reside within the HDAC9 sequence. Based on SVs within the HDAC9-TWIST1 locus, we defined the 3'-HDAC9 sequence as a critical TWIST1 regulatory region, encompassing craniofacial TWIST1 enhancers and CTCF sites. Deletions of either Twist1 enhancers (eTw5-7Δ/Δ) or CTCF site (CTCF-5Δ/Δ) within the Hdac9 protein-coding sequence led to decreased Twist1 expression and altered anterior/posterior limb expression patterns of SHH pathway genes. This decreased Twist1 expression results in a smaller sized and asymmetric skull and polydactyly that resembles Twist1+/- mouse phenotype. Chromatin conformation analysis revealed that the Twist1 promoter interacts with Hdac9 sequences that encompass Twist1 enhancers and a CTCF site, and that interactions depended on the presence of both regulatory regions. Finally, a large inversion of the entire Hdac9 sequence (Hdac9 INV/+) in mice that does not disrupt Hdac9 expression but repositions Twist1 regulatory elements showed decreased Twist1 expression and led to a craniosynostosis-like phenotype and polydactyly. Thus, our study elucidates essential components of TWIST1 transcriptional machinery that reside within the HDAC9 sequence. It suggests that SVs encompassing protein-coding sequences could lead to a phenotype that is not attributed to its protein function but rather to a disruption of the transcriptional regulation of a nearby gene.


Assuntos
Craniossinostoses , Histona Desacetilases , Proteínas Nucleares , Polidactilia , Proteínas Repressoras , Proteína 1 Relacionada a Twist , Animais , Craniossinostoses/genética , Regulação da Expressão Gênica , Histona Desacetilases/genética , Humanos , Camundongos , Proteínas Nucleares/genética , Fenótipo , Polidactilia/genética , Proteínas Repressoras/genética , Proteína 1 Relacionada a Twist/genética
6.
Phys Rev Lett ; 126(18): 185002, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34018793

RESUMO

We present the first observation of instability in weakly magnetized, pressure dominated plasma Couette flow firmly in the Hall regime. Strong Hall currents couple to a low frequency electromagnetic mode that is driven by high-ß (>1) pressure profiles. Spectroscopic measurements show heating (factor of 3) of the cold, unmagnetized ions via a resonant Landau damping process. A linear theory of this instability is derived that predicts positive growth rates at finite ß and shows the stabilizing effect of very large ß, in line with observations.

7.
Phys Rev Lett ; 126(14): 145001, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33891437

RESUMO

Supermagnetosonic perpendicular flows are magnetically driven by a large radius theta-pinch experiment. Fine spatial resolution and macroscopic coverage allow the full structure of the plasma-piston coupling to be resolved in laboratory experiment for the first time. A moving ambipolar potential is observed to reflect unmagnetized ions to twice the piston speed. Magnetized electrons balance the radial potential via Hall currents and generate signature quadrupolar magnetic fields. Electron heating in the reflected ion foot is adiabatic.

8.
Int J Drug Policy ; 90: 103080, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33340947

RESUMO

BACKGROUND: Harm reduction services, which typically provide overdose education and prevention with distribution of naloxone and other supplies related to safer drug use, help reduce opioid-related overdose and infectious disease transmission. However, structural stigma and the ongoing criminalization of drug use have limited the expansion of harm reduction services into many non-urban communities in the United States that have been increasingly affected by the health consequences of opioid and polysubstance use. METHODS: We conducted qualitative interviews with 22 professionals working with people who use drugs in cities and towns across Rhode Island and Massachusetts to understand challenges and strategies for engaging communities in accepting harm reduction perspectives and services. RESULTS: Our thematic analysis identified several interrelated challenges to implementing harm reduction services in non-urban communities, including: (1) limited understandings of harm reduction practice and preferential focus on substance use treatment and primary prevention, (2) community-level stigma against people who use drugs as well as the agencies supporting them, (3) data reporting and aggregating leading to inaccurate perceptions about local patterns of substance use and related health consequences, and (4) a "prosecutorial mindset" against drug use and harm reduction. From key informants' narratives, we also identified specific strategies that communities could use to address these challenges, including: (1) identifying local champions to advocate for harm reduction strategies, (2) proactively educating communities about harm reduction approaches before they are implemented, (3) improving the visibility of harm reduction services within communities, and (4) obtaining "buy-in" from a wide range of local stakeholders including law enforcement and local government. CONCLUSION: These findings carry important implications for expanding harm reduction services, including syringe service programs and safe injection sites, into non-urban communities that have a demonstrated need for evidence-based interventions to reduce drug-related overdose and infectious disease transmission.


Assuntos
Analgésicos Opioides , Overdose de Drogas , Redução do Dano , Humanos , Massachusetts , Rhode Island
9.
Phys Rev Lett ; 125(13): 135001, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33034476

RESUMO

A novel plasma equilibrium in the high-ß, Hall regime that produces centrally peaked, high Mach number Couette flow is described. Flow is driven using a weak, uniform magnetic field and large, cross field currents. Large magnetic field amplification (factor 20) due to the Hall effect is observed when electrons are flowing radially inward, and near perfect field expulsion is observed when the flow is reversed. A dynamic equilibrium is reached between the amplified (removed) field and extended density gradients.

10.
AJNR Am J Neuroradiol ; 40(11): 1796-1803, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31601576

RESUMO

BACKGROUND AND PURPOSE: Supratentorial primitive neuroectodermal tumors and pineoblastomas have traditionally been grouped together for treatment purposes. Molecular profiling of these tumors has revealed a number of distinct entities and has led to the term "CNS-primitive neuroectodermal tumors" being removed from the 2016 World Health Organization classification. The purpose of this study was to describe the MR imaging findings of histologically diagnosed primitive neuroectodermal tumors and pineoblastomas and correlate them with molecular diagnoses and outcomes. MATERIALS AND METHODS: Histologically diagnosed primitive neuroectodermal tumors and pineoblastomas were enrolled in this Children's Oncology Group Phase III trial, and molecular classification was retrospectively completed using DNA methylation profiling. MR imaging features were systematically studied and correlated with molecular diagnoses and survival. RESULTS: Of the 85 patients enrolled, 56 met the inclusion criteria, in whom 28 tumors were in pineal and 28 in nonpineal locations. Methylation profiling revealed a variety of diagnoses, including pineoblastomas (n = 27), high-grade gliomas (n = 17), embryonal tumors (n = 7), atypical teratoid/rhabdoid tumors (n = 3), and ependymomas (n = 2). Thus, 39% overall and 71% of nonpineal tumor diagnoses were discrepant with histopathology. Tumor location, size, margins, and edema were predictors of embryonal-versus-nonembryonal tumors. Larger size and ill-defined margins correlated with poor event-free survival, while metastatic disease by MR imaging did not. CONCLUSIONS: In nonpineal locations, only a minority of histologically diagnosed primitive neuroectodermal tumors are embryonal tumors; therefore, high-grade glioma or ependymoma should be high on the radiographic differential. An understanding of molecularly defined tumor entities and their relative frequencies and locations will help the radiologist make more accurate predictions of the tumor types.


Assuntos
Tumores Neuroectodérmicos Primitivos/diagnóstico por imagem , Tumores Neuroectodérmicos Primitivos/genética , Pinealoma/diagnóstico por imagem , Pinealoma/genética , Neoplasias Supratentoriais/diagnóstico por imagem , Neoplasias Supratentoriais/genética , Adolescente , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Criança , Pré-Escolar , Feminino , Glioma/diagnóstico por imagem , Glioma/genética , Glioma/patologia , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Neoplasias Embrionárias de Células Germinativas/diagnóstico por imagem , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Embrionárias de Células Germinativas/patologia , Tumores Neuroectodérmicos Primitivos/classificação , Tumores Neuroectodérmicos Primitivos/patologia , Glândula Pineal/diagnóstico por imagem , Glândula Pineal/patologia , Pinealoma/patologia , Estudos Retrospectivos , Tumor Rabdoide/diagnóstico por imagem , Tumor Rabdoide/genética , Tumor Rabdoide/patologia , Neoplasias Supratentoriais/patologia , Teratoma/diagnóstico por imagem , Teratoma/genética , Teratoma/patologia , Adulto Jovem
11.
J Dev Orig Health Dis ; 10(1): 108-114, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30626455

RESUMO

The preconception, pregnancy and immediate postpartum and newborn periods are times for mothers and their offspring when they are especially vulnerable to major stressors - those that are sudden and unexpected and those that are chronic. Their adverse effects can transcend generations. Stressors can include natural disasters or political stressors such as conflict and/or migration. Considerable evidence has accumulated demonstrating the adverse effects of natural disasters on pregnancy outcomes and developmental trajectories. However, beyond tracking outcomes, the time has arrived for gathering more information related to identifying mechanisms, predicting risk and developing stress-reducing and resilience-building interventions to improve outcomes. Further, we need to learn how to encapsulate both the quantitative and qualitative information available and share it with communities and authorities to mitigate the adverse developmental effects of future disasters, conflicts and migrations. This article briefly reviews prenatal maternal stress and identifies three contemporary situations (wildfire in Fort McMurray, Alberta, Canada; hurricane Harvey in Houston, USA and transgenerational and migrant stress in Pforzheim, Germany) where current studies are being established by Canadian investigators to test an intervention. The experiences from these efforts are related along with attempts to involve communities in the studies and share the new knowledge to plan for future disasters or tragedies.


Assuntos
Saúde Materna , Efeitos Tardios da Exposição Pré-Natal , Estresse Psicológico/terapia , Redação , Adolescente , Adulto , Canadá , Tempestades Ciclônicas , Desastres , Feminino , Migração Humana , Humanos , Pessoa de Meia-Idade , Gravidez , Resultado da Gravidez , Estresse Psicológico/complicações , Incêndios Florestais
12.
Spine (Phila Pa 1976) ; 43(15): E877-E884, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29985869

RESUMO

STUDY DESIGN: In a treatment-control animal study expansion thoracoplasty (ET) was performed in a juvenile rabbit model of thoracic insufficiency syndrome (TIS) and benefits to thoracic development and respiratory function quantified. Rabbits treated early versus late were compared to age-matched normal and disease control rabbits through to skeletal maturity. OBJECTIVE: Evaluate (1) how ET changes the natural TIS disease trajectory and (2) how timing of ET affects changes in spine growth, lung growth, and respiratory mechanics. SUMMARY OF BACKGROUND DATA: Pulmonary growth potential is thought to diminish with age; thus, early therapeutic intervention may increase pulmonary growth in children with TIS. However, no direct empirical evidence exists to support this treatment paradigm. METHODS: Convex left scoliosis and resultant TIS was induced in 3-week-old rabbits via surgical rib tethering. We compare the efficacy of ET performed at 7 weeks and expanded at 11 weeks (early, n = 7) versus only at 11 weeks of age (late, n = 7) in preserving lung growth and respiratory function relative to normal (n = 8) and disease (n = 10) rabbits. Sequential computed tomography images and pulmonary function testing was performed to quantify spine curvature, lung growth, and respiratory volumes. At 28 weeks of age chest wall elastance was measured in vivo then acinar complexity analyzed histologically via radial alveolar counts. RESULTS: ET performed early or late altered the predicted trajectory of spine deformity, pulmonary growth inhibition, and respiratory dysfunction seen in disease rabbits. Growth was not significantly different between early and late rabbits and post-treatment gains remained below those of age-matched normal rabbits. Chest wall elastance was impaired by ET and more so in early rabbits, there were no differences in pulmonary elastance. CONCLUSION: ET interrupted the natural progression of deformity and pulmonary hypoplasia associated with spine curvature in disease rabbits. However, growth benefits are only seen in cases of the most severe initial deformity and must be balanced against the further impairment to chest wall function associated with repetitive surgery. LEVEL OF EVIDENCE: N/A.


Assuntos
Pulmão/fisiopatologia , Insuficiência Respiratória/cirurgia , Escoliose/cirurgia , Toracoplastia/métodos , Animais , Medidas de Volume Pulmonar , Modelos Animais , Coelhos , Testes de Função Respiratória , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/fisiopatologia , Costelas/cirurgia , Escoliose/complicações , Escoliose/fisiopatologia , Resultado do Tratamento
13.
J Dairy Sci ; 101(10): 9185-9198, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29908806

RESUMO

Passive transfer of immunity is essential for the short- and long-term health of dairy calves. The objective of this study was to evaluate factors associated with colostrum quality and passive transfer status of US heifer calves. This study included 104 operations in 13 states that participated in the calf component of the National Animal Health Monitoring System's Dairy 2014 study. This 18-mo longitudinal study included 1,972 Holstein heifer calves from birth to weaning. Multivariable mixed linear regression models were selected using backward elimination model selection after univariate screening to determine which factors were associated with colostrum IgG and serum IgG concentrations. The mean colostrum IgG concentration was 74.4 g/L with 77.4% of colostrum samples having IgG concentrations >50 g/L. The final model for colostrum IgG included colostrum source and a categorized temperature-humidity index value (cTHI) for the month before calving. Mean colostrum IgG concentrations were highest for dams in third and higher lactations (84.7 g/L) and lowest for commercial colostrum replacers (40.3 g/L). Colostrum IgG concentrations were highest for cTHI ≥70 (72.6 g/L) and lowest for cTHI <40 (64.2 g/L). The mean serum IgG concentration was 21.6 g/L, with 73.3% of calves having serum IgG concentrations >15 g/L. The final model for serum IgG concentration included region, heat treatment of colostrum, colostrum source, timing to first feeding, volume of colostrum fed in the first 24 h, age of the calf at blood sampling, and colostrum IgG concentration. Mean serum IgG concentrations were highest for calves that received colostrum from first-lactation dams (25.7 g/L) and lowest for calves fed commercial colostrum replacer (16.6 g/L). Serum IgG concentrations were higher for calves fed heat-treated colostrum (24.4 g/L) than for calves fed untreated colostrum (20.5 g/L). Serum IgG concentration was positively associated with the volume of colostrum fed in the first 24 h and colostrum IgG concentration, and negatively associated with the number of hours from birth to colostrum feeding and age (days) at blood collection. Dairy producers should be encouraged to measure the quality of colostrum before administering it to calves and to measure serum IgG or a proxy such as serum total protein or Brix to evaluate passive immunity and colostrum management programs.


Assuntos
Bovinos , Colostro/imunologia , Imunização Passiva/veterinária , Imunoglobulina G/sangue , Animais , Animais Recém-Nascidos , Bovinos/imunologia , Feminino , Estudos Longitudinais , Gravidez , Desmame
14.
J Dairy Sci ; 101(10): 9168-9184, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29908815

RESUMO

The objective of this study was to describe preweaned dairy heifer calf management practices on dairy operations across the United States that were used to analyze factors associated with colostrum quality and passive transfer, Cryptosporidium and Giardia, morbidity and mortality, and average daily gain. This study included 104 dairy operations in 13 states that participated in the National Animal Health Monitoring System's Dairy 2014 calf component study. This 18-mo longitudinal study focused on dairy heifer calves from birth to weaning, and data were collected on 2,545 heifer calves. Descriptive statistics were generated regarding colostrum feeding, preweaning housing, milk feeding and consumption, growth, morbidity and mortality, and weaning practices. The majority of calves enrolled were Holsteins (89.4%). Over half the calves (63.2%) enrolled in the study received the majority of their colostrum via bottle; however, 22.1% of calves from 51.0% of operations received colostrum via suckling from their dams. For all calves, the mean time to the first colostrum feeding was 2.8 h, and the average amount of colostrum at the first feeding was 2.9 L, with 4.5 L provided in the first 24 h. The mean serum IgG of all calves was 21.7 g/L; however, 76.0% of operations had at least 1 calf with failure of passive transfer of immunity with a serum IgG below 10 g/L. The majority of calves in the study were housed individually (86.6%). Nonetheless, 20.2% of operations housed some calves in groups, representing 13.4% of all calves. Approximately one-half of the calves in the study (52.3%) were dehorned or disbudded during the preweaning period, with only 27.8% of these calves receiving analgesics or anesthetics during the procedure. Whole or waste milk was the liquid diet type fed to 40.1% of calves, and milk replacer was fed to 34.8% of calves. A combination of milk and milk replacer was fed to 25.1% of calves. Calves, on average, were fed 2.6 L per feeding and fed 2.6 times/d, resulting in a total of 5.6 L of liquid diet fed per day. The mean average daily gain for all calves enrolled in the study was 0.7 kg/d. Fecal samples were collected and almost all operations had at least 1 calf positive for Cryptosporidium (94.2%) or Giardia (99.0%), and 84.6% of operations had calves that tested positive for both Cryptosporidium and Giardia. Over one-third of calves (38.1%) had at least one morbidity event during the preweaning period and the mortality rate was 5.0%. The mean age at weaning was 65.7 d. This study provides an update on dairy heifer raising practices in the United States.


Assuntos
Animais Lactentes , Bovinos , Colostro/imunologia , Indústria de Laticínios/métodos , Desmame , Ração Animal , Animais , Animais Lactentes/crescimento & desenvolvimento , Animais Lactentes/imunologia , Dieta , Feminino , Estudos Longitudinais , Leite , Substitutos do Leite , Gravidez
15.
J Dairy Sci ; 101(10): 9229-9244, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29935825

RESUMO

The objective of this study was to evaluate morbidity and mortality in preweaned dairy heifer calves based on different health, feeding, and management practices, as well as environmental factors. This study was conducted as part of the calf component of the National Animal Health Monitoring System's Dairy 2014 study, which included 104 dairy operations in 13 states. The calf component was an 18-mo longitudinal study focused on dairy heifer calves from birth to weaning; data were collected on 2,545 calves. The percentage morbidity for all calves enrolled in the study was 33.9%. Backward elimination model selection was used after univariate screening to determine which management practices and environmental factors significantly affected morbidity and mortality. The final morbidity model included birth weight, serum IgG concentration, ventilation type, and average temperature-humidity index (THI) during the preweaning period. After controlling for other independent variables in the model, calves born at a higher birth weight had a lower predicted risk of morbidity than calves with a lower birth weight. An increase in serum IgG concentration was associated with decreased morbidity. Calves housed in positive- or cross-ventilated systems had a 2.2 times higher odds of developing disease compared with calves housed in natural ventilation systems. Average THI during the preweaning period was inversely correlated with morbidity; as THI increased, the predicted morbidity risk decreased. The percent mortality for all calves enrolled in the study was 5.0%. The final mortality model included birth weight, serum IgG concentration, amount of fat/day in the liquid diet, and morbidity. After controlling for other independent variables in the model, calves born at a higher birth weight had a lower risk of mortality. An increase in serum IgG concentration decreased the risk of mortality. The odds of mortality were 3.1 times higher in calves fed ≤0.15 kg of fat/d in the liquid diet compared with calves fed ≥0.22 kg of fat/d. The odds of mortality were 4.7 times higher in calves that experienced any disease throughout the preweaning period than in calves with no disease. In summary, morbidity and mortality were both associated with birth weight and serum IgG concentration. Additionally, morbidity was associated with ventilation type and average monthly THI, and mortality was associated with amount of fat per day in the liquid diet and morbidity.


Assuntos
Criação de Animais Domésticos/métodos , Animais Lactentes , Doenças dos Bovinos/mortalidade , Animais , Bovinos , Feminino , Estudos Longitudinais , Parto , Gravidez , Fatores de Risco
16.
J Dairy Sci ; 101(10): 9245-9258, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29803425

RESUMO

The study objective was to evaluate average daily gain (ADG) in dairy heifer calves based on health, feeding, management practices, and environmental factors. This study included 102 operations in 13 states that participated in the calf component of the National Animal Health Monitoring System's Dairy 2014 study. This 18-mo longitudinal study included 1,410 Holstein heifer calves monitored from birth to weaning. The mean ADG from birth to final weight was 0.74 kg/d. Backward elimination model selection in Proc Mixed after univariate screening determined factors that significantly affected ADG. The final model included dam lactation number, singleton versus twin birth, bedding type, Giardia and Cryptosporidium fecal shedding, disease events, a categorized average temperature-humidity index for the preweaning period (pTHI), amount of protein in the liquid diet (kg/d), milk pasteurization, direct-fed microbials, and the interaction between milk pasteurization and direct-fed microbials. After controlling for other independent variables in the model, calves born to first-lactation dams gained less (0.60 kg/d) than calves from second- (0.65 kg/d) or third- or greater-lactation (0.64 kg/d) dams. Singleton calves gained 0.07 kg/d more than twins. Calves bedded with sand or no bedding gained less (0.49 kg/d) than calves on all other bedding types. Calves negative for Cryptosporidium or Giardia at the time of sampling gained 0.03 or 0.02 kg/d more, respectively, than calves that were positive for Cryptosporidium or Giardia. Calves with no disease events gained 0.07 kg/d more than calves with one or more disease events. Calves experiencing an average pTHI <50 gained more (0.67 kg/d) than calves experiencing an average pTHI from 50 to 69 (0.62 kg/d), or ≥70 (0.59 kg/d). Within the range of observed kilograms of protein fed per day in the liquid diet, every additional 0.1 kg of protein fed per day equated to 0.02 kg/d of gain. Calves fed milk replacer with a direct-fed microbial gained less (0.44 kg/d) than calves fed milk replacer without a direct-fed microbial (0.60 kg/d) and calves fed pasteurized or unpasteurized milk regardless of direct-fed microbial use. These results highlight the importance of feeding a quantity and quality of a liquid diet to achieve optimal growth, keeping calves free of disease, the type or status of bedding, and mitigating the effects of temperature and humidity on preweaning ADG.


Assuntos
Animais Lactentes/crescimento & desenvolvimento , Bovinos/crescimento & desenvolvimento , Ração Animal , Animais , Dieta , Feminino , Estudos Longitudinais , Leite , Desmame
17.
Br J Cancer ; 118(4): 462-470, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29348486

RESUMO

BACKGROUND: Copanlisib is a pan-class I phosphatidylinositol 3-kinase (PI3K) inhibitor with predominant PI3K-α/δ activity that has demonstrated clinical activity and manageable safety when administered as monotherapy in a phase II study. Combination therapy may overcome compensatory signalling that could occur with PI3K pathway inhibition, resulting in enhanced inhibitory activity, and preclinical studies of copanlisib with gemcitabine have demonstrated potent anti-tumour activity in vivo. METHODS: A phase I, open-label, dose-escalation study to evaluate the safety, tolerability and recommended phase II dose (RP2D) of copanlisib with gemcitabine or with cisplatin plus gemcitabine (CisGem) in patients with advanced malignancies, including an expansion cohort in patients with biliary tract cancer (BTC) at the RP2D of copanlisib plus CisGem. Copanlisib and gemcitabine were administered on days 1, 8 and 15 of a 28-day cycle; maximum tolerated dose (MTD) and RP2D of copanlisib were determined. Copanlisib plus CisGem was administered on days 1 and 8 of a 21-day cycle; pharmacokinetics and biomarkers were assessed. RESULTS: Fifty patients received treatment as follows: dose-escalation cohorts, n=16; copanlisib plus CisGem cohort, n=14; and BTC expansion cohort, n=20. Copanlisib 0.8 mg kg-1 plus gemcitabine was the MTD and RP2D for both combinations. Common treatment-emergent adverse events included nausea (86%), hyperglycaemia (80%) and decreased platelet count (80%). Copanlisib exposure displayed a dose-proportional increase. No differences were observed upon co-administration of CisGem. Response rates were as follows: copanlisib plus gemcitabine, 6.3% (one partial response in a patient with peritoneal carcinoma); copanlisib plus CisGem, 12% (one complete response and three partial responses all in patients with BTC (response rate 17.4% in patients with BTC)). Mutations were detected in PIK3CA (1 out of 43), KRAS (10 out of 43) and BRAF (2 out of 22), with phosphate and tensin homologue protein loss in 41% (12 out of 29). CONCLUSIONS: Copanlisib plus CisGem demonstrated a manageable safety profile, favourable pharmacokinetics, and potentially promising clinical response.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias do Sistema Biliar/tratamento farmacológico , Cisplatino/administração & dosagem , Desoxicitidina/análogos & derivados , Pirimidinas/administração & dosagem , Quinazolinas/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Sistema Biliar/genética , Cisplatino/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Esquema de Medicação , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Mutação , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Pirimidinas/efeitos adversos , Quinazolinas/efeitos adversos , Resultado do Tratamento , Gencitabina
18.
Exp Neurol ; 302: 75-84, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29291403

RESUMO

The delivery of a nerve insult (a "conditioning lesion") prior to a subsequent test lesion increases the number of regenerating axons and accelerates the speed of regeneration from the test site. A major barrier to clinical translation is the lack of an ethically acceptable and clinically feasible method of conditioning that does not further damage the nerve. Conditioning electrical stimulation (CES), a non-injurious intervention, has previously been shown to improve neurite outgrowth in vitro. In this study, we examined whether CES upregulates regeneration-associated gene (RAG) expression and promotes nerve regeneration in vivo, similar to a traditional nerve crush conditioning lesion (CCL). Adult rats were divided into four cohorts based on conditioning treatment to the common peroneal (fibular) nerve: i) CES (1h, 20Hz); ii) CCL (10s crush); iii) sham CES (1h, 0Hz); or iv) naïve (unconditioned). Immunofluorescence and qRT-PCR revealed significant RAG upregulation in the dorsal root ganglia of both CES and CCL animals, evident at 3-14days post-conditioning. To mimic a clinical microsurgical nerve repair, all cohorts underwent a common peroneal nerve cut and coaptation one week following conditioning. Both CES and CCL animals increased the length of nerve regeneration (3.8-fold) as well as the total number of regenerating axons (2.2-fold), compared to the sham and naïve-conditioned animals (p<0.001). These data support CES as a non-injurious conditioning paradigm that is comparable to a traditional CCL and is therefore a novel means to potentially enhance peripheral nerve repair in the clinical setting.


Assuntos
Terapia por Estimulação Elétrica/métodos , Regulação da Expressão Gênica/fisiologia , Regeneração Nervosa/fisiologia , Neuropatias Fibulares/terapia , Análise de Variância , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Modelos Animais de Doenças , Proteína GAP-43/genética , Proteína GAP-43/metabolismo , Gânglios Espinais/metabolismo , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Neuroglia/metabolismo , Neuroglia/patologia , Neurônios/metabolismo , Neurônios/patologia , Neuropatias Fibulares/patologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
19.
Sci Rep ; 7(1): 9455, 2017 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-28842674

RESUMO

Fluorescence guided surgery (FGS) using aminolevulinic-acid (ALA) induced protoporphyrin IX (PpIX) provides intraoperative visual contrast between normal and malignant tissue during resection of high grade gliomas. However, maps of the PpIX biodistribution within the surgical field based on either visual perception or the raw fluorescence emissions can be masked by background signals or distorted by variations in tissue optical properties. This study evaluates the impact of algorithmic processing of hyperspectral imaging acquisitions on the sensitivity and contrast of PpIX maps. Measurements in tissue-simulating phantoms showed that (I) spectral fitting enhanced PpIX sensitivity compared with visible or integrated fluorescence, (II) confidence-filtering automatically determined the lower limit of detection based on the strength of the PpIX spectral signature in the collected emission spectrum (0.014-0.041 µg/ml in phantoms), and (III) optical-property corrected PpIX estimates were more highly correlated with independent probe measurements (r = 0.98) than with spectral fitting alone (r = 0.91) or integrated fluorescence (r = 0.82). Application to in vivo case examples from clinical neurosurgeries revealed changes to the localization and contrast of PpIX maps, making concentrations accessible that were not visually apparent. Adoption of these methods has the potential to maintain sensitive and accurate visualization of PpIX contrast over the course of surgery.


Assuntos
Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Neurocirurgia , Cirurgia Assistida por Computador/métodos , Algoritmos , Ácido Aminolevulínico/metabolismo , Processamento Eletrônico de Dados , Humanos , Imagem Óptica , Imagens de Fantasmas , Fármacos Fotossensibilizantes/metabolismo , Protoporfirinas/metabolismo
20.
J Liposome Res ; 27(3): 195-209, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28480760

RESUMO

By selecting a unique combination of lipids and amphotericin B, the liposome composition for AmBisome® (L-AmBis) has been optimized resulting in a formulation that is minimally toxic, targets to fungal cell walls, and distributes into and remains for days to weeks in various host tissues at drug levels above the MIC for many fungi. Procedures have been standardized to ensure that large scale production of the drug retains the drug's low toxicity profile, favorable pharmacokinetics and antifungal efficacy. Tissue accumulation and clearance with single or multiple intravenous administration is similar in uninfected and infected animal species, with tissue accumulation being dose-dependent and the liver and spleen retaining the most drug. The efficacy in animals appears to be correlated with drug tissue levels although the amount needed in a given organ varies depending upon the type of infection. The long-term tissue retention of bioactive L-AmBis in different organs suggests that for some indications, prophylactic and intermittent drug dosing would be efficacious reducing the cost and possible toxic side-effects. In addition, preliminary preclinical studies using non-intravenous routes of delivery, such as aerosolized L-AmBis, catheter lock therapy, and intravitreal administration, suggest that alternative routes could possibly provide additional therapeutic applications for this antifungal drug.


Assuntos
Anfotericina B/administração & dosagem , Anfotericina B/farmacologia , Antifúngicos/administração & dosagem , Antifúngicos/farmacologia , Micoses/tratamento farmacológico , Anfotericina B/efeitos adversos , Anfotericina B/farmacocinética , Animais , Antifúngicos/efeitos adversos , Antifúngicos/farmacocinética , Química Farmacêutica , Relação Dose-Resposta a Droga , Liberação Controlada de Fármacos , Humanos , Lipossomos , Fígado/metabolismo , Baço/metabolismo , Distribuição Tecidual
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...