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2.
medRxiv ; 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37873176

RESUMO

Background: Post-traumatic stress disorder (PTSD) and chronic pain are highly prevalent comorbid conditions. Veterans dually burdened by PTSD and chronic pain experience more severe outcomes compared to either disorder alone. Few studies have enrolled enough women Veterans to test gender differences in pain outcomes [catastrophizing, intensity, interference] by the severity of PTSD. Aim: Examine gender differences in the association between PTSD symptoms and pain outcomes among Veterans enrolled in a chronic pain clinical trial. Methods: Participants were 421 men and 386 women Veterans with chronic pain who provided complete data on PTSD symptoms and pain outcomes. We used hierarchical linear regression models to examine gender differences in pain outcomes by PTSD symptoms. Results: Adjusted multivariable models indicated that PTSD symptoms were associated with higher levels of pain catastrophizing (0.57, 95% CI [0.51, 0.63]), pain intensity (0.30, 95% CI [0.24, 0.37]), and pain interference (0.46, 95% CI [0.39, 0.52]). No evidence suggesting differences in this association were found in either the crude or adjusted models (all interaction p-values<0.05). Conclusion: These findings may reflect the underlying mutual maintenance of these conditions whereby the sensation of pain could trigger PTSD symptoms, particularly if the trauma and pain are associated with the same event. Clinical implications and opportunities testing relevant treatments that may benefit both chronic pain and PTSD are discussed.

3.
BMC Sports Sci Med Rehabil ; 14(1): 200, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36447290

RESUMO

BACKGROUND: The International Match Calendar congestion affects players recovery. The views of a worldwide cohort of professional football players is shared in this communication. METHODS: A cross-sectional observational study recruited players through Fédération Internationale des Associations de Footballeurs Professionnel's national members. An electronic survey was shared in English, French, Italian and Spanish with 1055 players consenting and completing it anonymously in November 2021. RESULTS: A total of 42% of respondents believe back-to-back matches should be limited to three. Most respondents (69%) felt off or in season breaks are infringed by clubs or national teams and 83% believe regulations should protect them. A total of 55% of players believed they sustained one or more injuries due to the overload and it has affected 52% of respondents' mental state. CONCLUSION: The congested International Match Calendar poses a risk to professional footballers physical and mental health. Poor recovery between matches may affect player availability and performance. Players should be represented by active players when International Match Calendar scheduling decisions are made. Administrators should seek medical guidance regarding the effects of overload on performance prior to making decisions. This study allows the opportunity for a larger national team player sample to be studied.

4.
Combust Sci Technol ; 195(15)2022.
Artigo em Inglês | MEDLINE | ID: mdl-37965054

RESUMO

The influence of CF3I on the burning velocity of methane-air flame is experimentally and numerically studied. Experimental results demonstrate that the inhibition effectiveness of CF3I is very close to that of CF3Br. A detailed kinetic model of flame inhibition by CF3I is presented, based on an updated version of a previous model. The kinetic model contains 1072 reactions with 115 species including 10 iodine-containing species. Modeling results demonstrate good agreement with experimental data, and both experiments and calculations show that CF3I is only slightly less effective at reducing the burning velocity than CF3Br. The flame structure predicted from numerical simulations is analyzed and shows that main reactions of the inhibition cycle of CF3I are: H+HI=H2+I; H+I+M=HI+M; I+I+M=I2+M; H+I2=HI+I; I+CH3+M=CH3I+M; H+CH3I=CH3+HI; I+HCO=HI+CO; HI+OH=H2O+I and O+HI=I+OH.

5.
Psychoneuroendocrinology ; 133: 105382, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34419762

RESUMO

Very little is known about maternal cerebral changes during pregnancy. Since there is an increased risk for major depression during pregnancy and postpartum, it is important to understand the structural and neurochemical changes that occur in the brain during pregnancy. Using proton magnetic resonance spectroscopy (1H-MRS) (3 T field strength), glutamate (Glu) levels were measured in the medial prefrontal cortex (MPFC) of 21 healthy gravid subjects 2-3 weeks before their due date (6.74 ± 1.39), and in 14 non-pregnant healthy controls during their follicular phase (8.53 ± 1.55). Water quantified MPFC Glu levels were decreased in pregnant women (p < 0.01). We also observed a 13.9% decrease in percentage grey matter (%GM) (p < 0.01) in our MPFC voxel. As Glu is mostly found in GM, we repeated the statistical analysis after adjustment for %GM and found that the difference in Glu levels was no longer statistically significant when adjusted for %GM (p = 0.10). This investigation is the only systematic direct investigation of brain tissue composition and Glu levels in pregnant women. The main finding of this investigation is the decreased %GM in healthy pregnant women compared to non-pregnant women. These findings of decreased %GM in pregnancy may be responsible for the frequent complaints by pregnant women of cognitive difficulties also described as pregnesia.


Assuntos
Ácido Glutâmico , Córtex Pré-Frontal , Estudos de Casos e Controles , Feminino , Ácido Glutâmico/metabolismo , Humanos , Córtex Pré-Frontal/metabolismo , Gravidez , Gestantes , Espectroscopia de Prótons por Ressonância Magnética
6.
Nature ; 576(7786): 237-242, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31802007

RESUMO

During the solar minimum, when the Sun is at its least active, the solar wind1,2 is observed at high latitudes as a predominantly fast (more than 500 kilometres per second), highly Alfvénic rarefied stream of plasma originating from deep within coronal holes. Closer to the ecliptic plane, the solar wind is interspersed with a more variable slow wind3 of less than 500 kilometres per second. The precise origins of the slow wind streams are less certain4; theories and observations suggest that they may originate at the tips of helmet streamers5,6, from interchange reconnection near coronal hole boundaries7,8, or within coronal holes with highly diverging magnetic fields9,10. The heating mechanism required to drive the solar wind is also unresolved, although candidate mechanisms include Alfvén-wave turbulence11,12, heating by reconnection in nanoflares13, ion cyclotron wave heating14 and acceleration by thermal gradients1. At a distance of one astronomical unit, the wind is mixed and evolved, and therefore much of the diagnostic structure of these sources and processes has been lost. Here we present observations from the Parker Solar Probe15 at 36 to 54 solar radii that show evidence of slow Alfvénic solar wind emerging from a small equatorial coronal hole. The measured magnetic field exhibits patches of large, intermittent reversals that are associated with jets of plasma and enhanced Poynting flux and that are interspersed in a smoother and less turbulent flow with a near-radial magnetic field. Furthermore, plasma-wave measurements suggest the existence of electron and ion velocity-space micro-instabilities10,16 that are associated with plasma heating and thermalization processes. Our measurements suggest that there is an impulsive mechanism associated with solar-wind energization and that micro-instabilities play a part in heating, and we provide evidence that low-latitude coronal holes are a key source of the slow solar wind.

7.
Behav Brain Res ; 362: 249-257, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30633938

RESUMO

Maternal alcohol consumption throughout pregnancy can result in long term behavioural deficits in offspring. However, less is known about the impact of alcohol during the periconceptional period (PC). The aim of this study was to examine the effect of PC ethanol (PC:EtOH) exposure on long term cognitive function; including memory and anxiety. Rats were exposed to a liquid diet containing ethanol (EtOH) (12.5% vol;vol) or a control diet from 4 days prior to mating until day 4 of pregnancy. Separate cohorts of animals were tested at 6 months (adult) or 15-18 months of age (aged). Offspring underwent a series of behavioural tests to assess anxiety, spatial and recognition memory. The hippocampus was collected, and mRNA expression of epigenetic modifiers and genes implicated in learning and memory were examined. PC:EtOH exposure resulted in a subtle anxiety like behaviour in adult female offspring with a significant reduction in directed exploring/head dipping behaviour during holeboard testing. In aged male offspring, PC:EtOH exposure resulted in a tendency for increased directed exploring/head dipping behaviour during holeboard testing. No differences between treatments were observed in the elevated plus maze. Aged female offspring exposed to PC:EtOH demonstrated short term spatial memory impairment (P < 0.05). PC:EtOH resulted in an upregulation of hippocampal mRNA expression of bdnf, grin2a and grin2b at 18 months of age along with increased expression of epigenetic modifiers (dnmt1, dnmt3a and hdac2). In conclusion, PC:EtOH can lead to sex specific anxiety-like behaviour and impairments in spatial memory and altered hippocampal gene expression.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Etanol/farmacologia , Expressão Gênica/efeitos dos fármacos , Memória/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Animais , Ansiedade/etiologia , Comportamento Animal/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Gravidez , Ratos Sprague-Dawley
8.
Clin Microbiol Infect ; 25(1): 92-95, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29674129

RESUMO

OBJECTIVES: Polymyxins have been revitalized to combat carbapenem-resistant Enterobacteriaceae (CRE). However, evaluating the activity of these agents by traditional broth dilution methods is not practical for busy clinical laboratories. We compared polymyxin B activity using two quantitative susceptibility testing methods, Etest® and broth microdilution (BMD), against CRE isolates from patients at an academic medical centre. METHODS: Polymyxin B activity against 70 CRE clinical isolates was determined by Etest® according to the manufacturer and by BMD according to CLSI guidelines. Pseudomonas aeruginosa ATCC® 27853 and Escherichia coli NCTC 13846 served as quality control strains. The EUCAST colistin susceptibility breakpoint of Enterobacteriaceae (≤2 mg/L) was used. Essential agreement was isolates with an MIC within 1 log2 dilution over total isolates. Categorical agreement was number of isolates in the same susceptibility category (susceptible or resistant) over total isolates. Major and very major error rates were calculated using number of susceptible and number of resistant isolates, respectively, as the denominator. McNemar's test was used for determining a difference in susceptibility between methods. RESULTS: The CRE isolates were primarily Klebsiella spp. (49%) and Enterobacter spp. (36%). Polymyxin B susceptibility was significantly higher by Etest® compared with BMD (97% versus 77%; p 0.0001). Categorical agreement was 80%, but essential agreement was low (10%). False non-susceptibility was never observed by Etest® (BMD reference), but the very major errors were high (88%). CONCLUSIONS: Etest® reporting of false susceptibility may result in inappropriate antibiotic use and treatment failure clinically. We do not recommend using Etest® for polymyxin B susceptibility testing for routine patient care.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/normas , Testes de Sensibilidade Microbiana/métodos , Testes de Sensibilidade Microbiana/normas , Polimixina B/farmacologia , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos
9.
JDR Clin Trans Res ; 2(3): 249-257, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28879247

RESUMO

This study aims to investigate the prevalence of the highly leukotoxic JP2 sequence versus the minimally leukotoxic non-JP2 sequence of Aggregatibacter actinomycetemcomitans within a cohort of 180 young African Americans, with and without localized aggressive periodontitis (LAP), in north Florida. The study included patients aged 5 to 25 y: 60 LAP patients, 60 healthy siblings (HS), and 60 unrelated healthy controls (HC). Subgingival plaque was collected from LAP sites-diseased (PD ≥5 mm with bleeding on probing) and healthy (PD ≤3 mm with no bleeding on probing)-and from healthy sites of HS and HC. Plaque DNA was extracted and analyzed by polymerase chain reaction for the detection of the JP2 and non-JP2 sequences of A. actinomycetemcomitans. Overall, 90 (50%) subjects tested positive for the JP2 sequence. Fifty (83.33%) LAP subjects were carriers of the highly leukotoxic JP2 sequence, detected in 45 (75%) diseased sites and 34 (56.67%) healthy sites. Additionally, JP2 carriage was found in 16 HS (26.67%) and 24 HC (40%; P < 0.0001, among groups). The non-JP2 sequence was detected in 26 (14.44%) total subjects: 17 (28.33%) LAP patients detected in equal amounts of diseased and healthy sites (n = 11, 18.33%), 6 (10%) HS sites, and 3 (5%) HC sites (P < 0.05, among groups). The JP2 sequence was strongly associated with LAP-diseased sites in young African Americans, significantly more so than the non-JP2 (ClinicalTrials.gov NCT01330719). Knowledge Transfer Statement: Clinicians may use the results of this study to identify susceptible individuals to aggressive periodontitis, potentially leading to more appropriate selection of therapeutic choices.

10.
Methods Cell Biol ; 137: 1-13, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28065299

RESUMO

Sea urchins have long been used as a model organism to address questions in cell biology and development. Work utilizing this model has elucidated processes of fertilization, the description of centrosomes, the separation of chromosomes during mitosis, and numerous other landmark discoveries. They have been a favorite among researchers for a variety of reasons: Eggs are large and malleable, making them relatively easy to work with; the embryos have synchronized, rapid divisions; they are easy to microinject and manipulate; and their genome sequence is available. In this Chapter, we focus on methods used to study the membrane dynamics during cytokinesis using sea urchin embryos. The focus of this chapter is to provide methods for live-cell imaging of membrane domains in sea urchin embryos.


Assuntos
Citocinese/genética , Microdomínios da Membrana/ultraestrutura , Biologia Molecular/métodos , Imagem Molecular/métodos , Animais , Cromossomos/genética , Desenvolvimento Embrionário/genética , Fertilização/genética , Microdomínios da Membrana/genética , Mitose/genética , Oócitos/crescimento & desenvolvimento , Ouriços-do-Mar/genética , Ouriços-do-Mar/crescimento & desenvolvimento
11.
Phys Rev Lett ; 117(9): 095101, 2016 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-27610862

RESUMO

Particle dynamics are investigated in plasma turbulence, using self-consistent kinetic simulations, in two dimensions. In the steady state, the trajectories of single protons and proton pairs are studied, at different values of plasma ß (ratio between kinetic and magnetic pressure). For single-particle displacements, results are consistent with fluids and magnetic field line dynamics, where particles undergo normal diffusion for very long times, with higher ß's being more diffusive. In an intermediate time range, with separations lying in the inertial range, particles experience an explosive dispersion in time, consistent with the Richardson prediction. These results, obtained for the first time with a self-consistent kinetic model, are relevant for astrophysical and laboratory plasmas, where turbulence is crucial for heating, mixing, and acceleration processes.

12.
Aust Vet J ; 94(5): 166-170, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27113988

RESUMO

CASE REPORT: A 10-week-old male Labrador Retriever puppy was presented for acute onset of vomiting over a 48-h period. Ultrasound examination showed a cystic structure in the area of the pylorus that was impinging on gastric outflow. Surgery was performed to resect this structure. Histological examination showed the cystic structure to be composed of gastric mucosa surrounded by a smooth muscle wall. This finding, together with the intraoperative observations, led to a definitive diagnosis of a non-communicating gastric duplication cyst. CONCLUSION: Although rare, gastric duplication cyst is a differential diagnosis for acute-onset vomiting in a young dog. This report should aid in the decision-making process in future cases.

13.
Space Sci Rev ; 204(1-4): 49-82, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29755144

RESUMO

NASA's Solar Probe Plus (SPP) mission will make the first in situ measurements of the solar corona and the birthplace of the solar wind. The FIELDS instrument suite on SPP will make direct measurements of electric and magnetic fields, the properties of in situ plasma waves, electron density and temperature profiles, and interplanetary radio emissions, amongst other things. Here, we describe the scientific objectives targeted by the SPP/FIELDS instrument, the instrument design itself, and the instrument concept of operations and planned data products.

14.
Phys Rev Lett ; 115(12): 125001, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26430997

RESUMO

Shock waves exist throughout the Universe and are fundamental to understanding the nature of collisionless plasmas. Reformation is a process, driven by microphysics, which typically occurs at high Mach number supercritical shocks. While ongoing studies have investigated this process extensively both theoretically and via simulations, their observations remain few and far between. In this Letter we present a study of very high Mach number shocks in a parameter space that has been poorly explored and we identify reformation using in situ magnetic field observations from the Cassini spacecraft at 10 AU. This has given us an insight into quasiperpendicular shocks across 2 orders of magnitude in Alfvén Mach number (M_{A}) which could potentially bridge the gap between modest terrestrial shocks and more exotic astrophysical shocks. For the first time, we show evidence for cyclic reformation controlled by specular ion reflection occurring at the predicted time scale of ~0.3τ_{c}, where τ_{c} is the ion gyroperiod. In addition, we experimentally reveal the relationship between reformation and M_{A} and focus on the magnetic structure of such shocks to further show that for the same M_{A}, a reforming shock exhibits stronger magnetic field amplification than a shock that is not reforming.

15.
Obes Rev ; 16(4): 319-26, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25752756

RESUMO

The objective of this study was to critically review the empirical evidence from all relevant disciplines regarding obesity stigma in order to (i) determine the implications of obesity stigma for healthcare providers and their patients with obesity and (ii) identify strategies to improve care for patients with obesity. We conducted a search of Medline and PsychInfo for all peer-reviewed papers presenting original empirical data relevant to stigma, bias, discrimination, prejudice and medical care. We then performed a narrative review of the existing empirical evidence regarding the impact of obesity stigma and weight bias for healthcare quality and outcomes. Many healthcare providers hold strong negative attitudes and stereotypes about people with obesity. There is considerable evidence that such attitudes influence person-perceptions, judgment, interpersonal behaviour and decision-making. These attitudes may impact the care they provide. Experiences of or expectations for poor treatment may cause stress and avoidance of care, mistrust of doctors and poor adherence among patients with obesity. Stigma can reduce the quality of care for patients with obesity despite the best intentions of healthcare providers to provide high-quality care. There are several potential intervention strategies that may reduce the impact of obesity stigma on quality of care.


Assuntos
Obesidade/psicologia , Atenção Primária à Saúde , Qualidade da Assistência à Saúde/estatística & dados numéricos , Estigma Social , Atitude do Pessoal de Saúde , Necessidades e Demandas de Serviços de Saúde , Humanos , Relações Profissional-Paciente , Qualidade da Assistência à Saúde/normas
16.
J R Army Med Corps ; 161(2): 150-2, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24970934

RESUMO

There is extensive literature on metal fragments from improvised explosive devices being embedded in patients but there are no reports describing the clinical and radiological appearances of embedded home-made explosive (HME). We present a case of partially detonated HME being found inside a patient's forearm. We discuss the medical management of the injury, the ongoing risk to the patient and surgical team associated with the explosive and the safe disposal of the substance.


Assuntos
Substâncias Explosivas , Traumatismos do Antebraço/cirurgia , Corpos Estranhos , Hospitais Militares , Adulto , Campanha Afegã de 2001- , Amputação Cirúrgica , Cloratos , Traumatismos do Antebraço/patologia , Humanos , Masculino , Medicina Militar , Militares , Equipamentos de Proteção , Adulto Jovem
17.
Aust Vet J ; 92(3): 81-4, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24571343

RESUMO

OBJECTIVE: Retrospective study to determine postoperative continence when correcting intramural ureteral ectopia by transection of the ureter and neoureterostomy, leaving the distal ureter in situ. We hypothesised that the technique would achieve results comparable to previously described surgical techniques. METHODS: Medical records for dogs that underwent surgery for correction of unilateral intramural ureteral ectopia were reviewed. Cases (n = 9) of a neoureterostomy where the distal ureter was left in situ were included. Postoperatively, owners were contacted by telephone or email and asked to complete a questionnaire, scoring their dog's urinary continence on a scale from 0 to 2 where 0 was completely continent, 1 was occasional incontinence during excitement or while recumbent and 2 was no improvement in postoperative urinary continence, with the dog having constantly wet perivulvar fur and constant dribbling of urine. RESULTS: All dogs showed signs of severe urinary incontinence prior to surgery, including constantly wet perivulvar fur and constant dribbling of urine. Postoperatively, six dogs had a score of 0 and three dogs improved to a score of 1. Time to follow-up after surgery ranged from 1 to 62 months. CONCLUSION: The results of this study support our hypothesis. The technique was simple to perform and urinary continence achieved was comparable to that of other techniques. We suggest that this technique should be considered as an alternative for the correction of intramural ureteral ectopia.


Assuntos
Doenças do Cão/cirurgia , Ureter/anormalidades , Ureterostomia/veterinária , Incontinência Urinária/veterinária , Animais , Doenças do Cão/congênito , Cães , Feminino , Prontuários Médicos , Cuidados Pós-Operatórios/veterinária , Queensland , Estudos Retrospectivos , Inquéritos e Questionários , Ureterostomia/métodos , Incontinência Urinária/cirurgia
18.
Res Vet Sci ; 95(2): 681-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23706903

RESUMO

Long-term, frequent venous access for diagnostic, therapeutic, or research purposes in cats is problematic. Frequent blood sampling over extended periods is necessary for some therapeutic regimes and often required for clinical research in veterinary science. In this paper, we describe the implantation of vascular access ports (VAPs) and assess their use for repeated blood sampling over 16 weeks and 38 weeks, as well as the use of jugular catheters for one week. The VAP placement procedure was well-tolerated with few minor complications (minor swelling, contusion, or superficial dermatitis from self-trauma), which were not observed when neck bandages were applied immediately after surgery. Thromboembolism occurred in two cats, but did not occur after switching to a smaller catheter with a rounded tip and taurolidine-citrate locking solution. Although duration of access was much longer with VAPs compared to jugular catheters, patency rates were similar (89% (n=28) to 92% (n=12) after 16 weeks and 75% (n=12) after 38 weeks for VAPs; 88% (n=49) after one week for jugular catheters). Behavioural reactions to blood collection from 30 cats-assessed over 16 weeks and comprising 378 collections-were absent or minor in 99% of collections. These findings indicate that VAPs offer a viable alternative to jugular catheters for studies requiring frequent blood sampling and lasting more than 2 weeks.


Assuntos
Coleta de Amostras Sanguíneas/veterinária , Gatos , Veias Jugulares , Flebotomia/veterinária , Dispositivos de Acesso Vascular/veterinária , Animais , Coleta de Amostras Sanguíneas/instrumentação , Cateteres de Demora/veterinária , Feminino , Masculino , Flebotomia/instrumentação , Flebotomia/métodos
19.
Anal Chem ; 84(20): 8837-8845, 2012 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-23039161

RESUMO

Biofouling and tissue inflammation present major challenges toward the realization of long-term implantable glucose sensors. Following sensor implantation, proteins and cells adsorb on sensor surfaces to not only inhibit glucose flux but also signal a cascade of inflammatory events that eventually lead to permeability-reducing fibrotic encapsulation. The use of drug-eluting hydrogels as outer sensor coatings has shown considerable promise to mitigate these problems via the localized delivery of tissue response modifiers to suppress inflammation and fibrosis, along with reducing protein and cell absorption. Biodegradable poly (lactic-co-glycolic) acid (PLGA) microspheres, encapsulated within a poly (vinyl alcohol) (PVA) hydrogel matrix, present a model coating where the localized delivery of the potent anti-inflammatory drug dexamethasone has been shown to suppress inflammation over a period of 1-3 months. Here, it is shown that the degradation of the PLGA microspheres provides an auxiliary venue to offset the negative effects of protein adsorption. This was realized by: (1) the creation of fresh porosity within the PVA hydrogel following microsphere degradation (which is sustained until the complete microsphere degradation) and (2) rigidification of the PVA hydrogel to prevent its complete collapse onto the newly created void space. Incubation of the coated sensors in phosphate buffered saline (PBS) led to a monotonic increase in glucose permeability (50%), with a corresponding enhancement in sensor sensitivity over a 1 month period. Incubation in serum resulted in biofouling and consequent clogging of the hydrogel microporosity. This, however, was partially offset by the generated macroscopic porosity following microsphere degradation. As a result of this, a 2-fold recovery in sensor sensitivity for devices with microsphere/hydrogel composite coatings was observed as opposed to similar devices with blank hydrogel coatings. These findings suggest that the use of macroscopic porosity can reduce sensitivity drifts resulting from biofouling, and this can be achieved synergistically with current efforts to mitigate negative tissue responses through localized and sustained drug delivery.


Assuntos
Anti-Inflamatórios/administração & dosagem , Incrustação Biológica/prevenção & controle , Técnicas Biossensoriais/instrumentação , Preparações de Ação Retardada/metabolismo , Dexametasona/administração & dosagem , Glucose/análise , Preparações de Ação Retardada/química , Glucose/metabolismo , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Hidrogel de Polietilenoglicol-Dimetacrilato/metabolismo , Ácido Láctico/metabolismo , Microesferas , Permeabilidade , Ácido Poliglicólico/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Álcool de Polivinil/química , Álcool de Polivinil/metabolismo , Porosidade , Sensibilidade e Especificidade
20.
Aust Vet J ; 90(8): 283-90, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22827621

RESUMO

OBJECTIVE: (1) To report whelping rates and litter sizes following coeliotomy-assisted intrauterine inseminations (CAII) performed commercially and (2) to identify factors that may influence these outcomes. DESIGN: Retrospective single cohort observational study. PROCEDURE: All oestrous cycles in bitches that presented to the study hospital for CAII between 1 January 2005 and 31 December 2010 were included. One insemination was performed per oestrus. Whelping and litter size following CAII were recorded. Potential determinants of these outcomes were assessed. RESULTS: Of 238 inseminations performed, 174 (73.1%) resulted in whelping. The known litter size ranged from 1 to 16 pups (mean ± SD 6.12 ± 3.12 pups). From univariable analyses, progressive motility percentage was the only variable significantly associated with odds of whelping (P = 0.020); bitch parity and weight were associated with litter size when adjusted for each other (P = 0.035 and 0.003, respectively). Inseminations performed with >200 × 10(6) progressively motile sperm were more likely to result in whelping relative to inseminations with >100-200 × 10(6) progressively motile sperm (odds ratio 3.61, 95% confidence interval 0.84-15.5, P = 0.084), and, in a separate model, relative to >75-125 × 10(6) progressively motile sperm (odds ratio 6.09, 95% confidence interval 1.41-26.36, P = 0.016). CONCLUSION: Whelping rates and litter sizes were similar to other case studies and the experimental reports of CAII. Progressive motility percentage affects the odds of whelping, and litter size is affected by both the weight and parity of the bitch. Importantly, these findings provide some evidence that whelping rates with CAII are not maximised unless more than 200 × 10(6) progressively motile sperm are inseminated.


Assuntos
Cães/fisiologia , Inseminação Artificial/veterinária , Tamanho da Ninhada de Vivíparos , Taxa de Gravidez , Motilidade dos Espermatozoides/fisiologia , Animais , Peso Corporal , Estudos de Coortes , Feminino , Inseminação Artificial/métodos , Paridade , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Útero
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