Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 46
Filtrar
1.
J Chem Phys ; 160(14)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38591683

RESUMO

The plasmonic coupling between silver (Ag) and gold (Au) nanoparticles (NPs) under four polarization modes was examined: a longitudinal mode (L-mode), where the electric field of a linearly polarized incident light parallels the dimer axis, and three transverse modes (T-modes), where the electric field of the light is perpendicular to the dimer axis. The coupling was studied using the discrete dipole approximation followed by an in-house postprocessing code that determines the extinction (Qext), absorption (Qabs), and near-field (Qnf) spectra from the individual NPs as well as the whole system. In agreement with the literature results, the extinction/absorption spectra of the whole dimer have two peaks, one near the Ag localized surface plasmon resonance (LSPR) region and the other at the Au LSPR region, with the peak at Ag LSPR being reduced in all modes and the peak at Au LSPR being red-shifted and increased in the L-mode but not in the T-modes. It is further shown that the scattering at the Ag LSPR region is reduced and becomes less than the isolated Ag NPs, but the absorption at the Ag LSPR is increased and becomes greater than the isolated Ag NPs for the 50 nm Ag-Au heterodimer. This suggests that the scattering from Ag NPs is being reabsorbed by the neighboring Au NPs due to the interband electronic transition in Au at that wavelength range. The Qext from the individual NP in the heterodimer shows the presence of the Fano profile on the Au NP but not on the Ag NP. This phenomenon was further investigated by using a dielectric particle (DP) placed near the Ag or Au NPs. The Fano profile appears in the absorbing DP spectra placed near either Ag or Au NPs. However, the Fano profile is masked upon further increases in the refractive index value of the DP particle. This explains the absence of a Fano profile on the Ag NPs in the Ag-Au heterodimer. The large near-field enhancement on both Ag and Au NPs at the Au plasmonic wavelength in the L-mode for large NPs was investigated through a DP-Au system. The large enhancement was shown to arise from a large imaginary component of the DP refractive index and a small real component. Through examination of both the near- and far-field properties of the individual NPs as well as the whole system and examinations of DP-Ag and DP-Au systems, our study provides a new understanding of the couplings between Ag and Au NPs.

2.
Nanomaterials (Basel) ; 13(21)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37947737

RESUMO

Gap-enhanced Raman tags are a new type of optical probe that have wide applications in sensing and detection. A gap-enhanced Raman tag is prepared by embedding Raman molecules inside a gap between two plasmonic metals such as an Au core and Au shell. Even though placing Raman molecules beneath an Au shell seems counter-intuitive, it has been shown that such systems produce a stronger surface-enhanced Raman scattering response due to the strong electric field inside the gap. While the theoretical support of the stronger electric field inside the gap was provided in the literature, a comprehensive understanding of how the electric field inside the gap compares with that of the outer surface of the particle was not readily available. We investigated Au@SiO2@Au nanoparticles with diameters ranging from 35 nm to 70 nm with varying shell (2.5-10 nm) and gap (2.5-15 nm) thicknesses and obtained both far-field and near-field spectra. The extinction spectra from these particles always have two peaks. The low-energy peak redshifts with the decreasing shell thickness. However, when the gap thickness decreases, the low-energy peaks first blueshift and then redshift, producing a C-shape in the peak position. For every system we investigated, the near-field enhancement spectra were stronger inside the gap than on the outer surface of the nanoparticle. We find that a thin shell combined with a thin gap will produce the greatest near-field enhancement inside the gap. Our work fills the knowledge gap between the exciting potential applications of gap-enhanced Raman tags and the fundamental knowledge of enhancement provided by the gap.

4.
JMIR Hum Factors ; 9(2): e35094, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35499866

RESUMO

BACKGROUND: Health professionals' perceptions of persuasive design techniques for use in technological solutions to improve health workforce capability have not been previously explored. OBJECTIVE: This study aims to explore rural health professionals' perceptions of health workforce capability and persuasive design techniques; and translate these into recommendations for designing a health workforce capability app to increase their impact and usefulness. METHODS: Qualitative interviews with 13 rural health professionals were conducted. Subsequently, 32 persuasive techniques were used as a framework to deductively analyze the data. Persuasive design technique domains were Primary Task Support, Dialog Support, System Credibility Support, Social Support, and Cialdini's Principles of Persuasion. RESULTS: Persuasive design techniques can be applied across the factors that influence health workforce capability including health and personal qualities; competencies and skills; values, attitudes, and motivation; and factors that operate outside of work and at the team, organizational, and labor market levels. The majority of the 32 persuasive design techniques were reflected in the data from the interviews and led to recommendations as to how these could be translated into practice, with the exception of scarcity. Many suggestions and persuasive design techniques link back to the need for tailored and localized solutions such as the need for country-specific-based evidence, the wish for localized communities of practice, learning from other rural health professionals, and referral pathways to other clinicians. Participants identified how persuasive design techniques can optimize the user experience to help meet rural health professionals needs for more efficient systems to improve patient access to care, quality care, and to enable working in interprofessional team-based care. Social inclusion plays a vital role for health professionals, indicating the importance of the Social Support domain of persuasive techniques. Overall, health professionals were open to self-monitoring of their work performance and some professionals used wearables to monitor their health. CONCLUSIONS: Rural health professionals' perceptions of health workforce capability informed which persuasive design techniques can be used to optimize the user experience of an app. These were translated into recommendations for designing a health workforce capability app to increase likelihood of adoption. This study has also contributed to the further validation of the Persuasive Systems Design model through empirically aligning elements of the model to increase persuasive system content and functionality with real-world applied data, in this case the health workforce capability of rural health professionals. Our findings confirm that these techniques can be used to develop a future prototype of an app that may assist health professionals in improving or maintaining their health workforce capability which in turn may increase recruitment and retention in rural areas. Health professionals need to be central during the design phase. Interventions are needed to provide a supportive environment to rural and remote health professionals to increase their rural health workforce capability.

5.
Sci Rep ; 12(1): 7051, 2022 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-35488011

RESUMO

Many lizard species use caudal autotomy, the ability to self-amputate a portion of the tail, as an effective but costly survival strategy. However, as a lizard grows, its increased size may reduce predation risk allowing for less costly strategies (e.g., biting and clawing) to be used as the primary defence. The King's skink (Egernia kingii) is a large scincid up to approximately 244 mm snout to vent length (SVL) in size when adult. Adults rely less on caudal autotomy than do juveniles due to their size and strength increase during maturation. It has been hypothesised that lower behavioural reliance on autotomy in adults is reflected in loss or restriction of caudal vertebrae fracture planes through ossification as caudal intra-vertebral fracture planes in some species ossify during ontogenetic growth. To test this, we used micro-CT to image the tails of a growth series of seven individuals of E. kingii. We show that fracture planes are not lost or restricted ontogenetically within E. kingii, with adults retaining between 39-44 autotomisable vertebrae following 5-6 non-autotomisable vertebrae. Even though mature E. kingii rely less on caudal autotomy than do juveniles, this research shows that they retain the maximum ability to autotomise their tails, providing a last resort option to avoid threats. The potential costs associated with retaining caudal autotomy are most likely mitigated through neurological control of autotomy and E. kingii's longevity.


Assuntos
Lagartos , Animais , Humanos , Comportamento Predatório
6.
J Dev Biol ; 9(4)2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34940500

RESUMO

Caudal autotomy, the ability to shed a portion of the tail, is a widespread defence strategy among lizards. Following caudal autotomy, and during regeneration, lizards face both short- and long-term costs associated with the physical loss of the tail and the energy required for regeneration. As such, the speed at which the individual regenerates its tail (regeneration rate) should reflect the fitness priorities of the individual. However, multiple factors influence the regeneration rate in lizards, making inter-specific comparisons difficult and hindering broader scale investigations. We review regeneration rates for lizards and tuatara from the published literature, discuss how species' fitness priorities and regeneration rates are influenced by specific, life history and environmental factors, and provide recommendations for future research. Regeneration rates varied extensively (0-4.3 mm/day) across the 56 species from 14 family groups. Species-specific factors, influencing regeneration rates, varied based on the type of fracture plane, age, sex, reproductive season, and longevity. Environmental factors including temperature, photoperiod, nutrition, and stress also affected regeneration rates, as did the method of autotomy induction, and the position of the tail also influenced regeneration rates for lizards. Additionally, regeneration could alter an individual's behaviour, growth, and reproductive output, but this varied depending on the species.

7.
J Phys Chem C Nanomater Interfaces ; 125(9): 5260-5268, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-34367408

RESUMO

Coupling between plasmonic nanoparticles (NPs) in nanoparticle assemblies has been investigated extensively via far-field properties, such as absorption and scattering, but very rarely via near-field properties, and a quantitative investigation of near-field properties should provide great insight into the nature of the coupling. We report a numerical procedure to obtain reliable near-field spectra (Q NF) around spherical gold nanoparticles (Au NPs) using Discrete Dipole Approximation (DDA). The reliability of the method was tested by comparing Q NF from DDA calculations with exact results from the Mie theory. We then applied the method to examine Au NPs assembled in dimer, trimer, and up to pentamer in a linear arrangement. For the well-studied dimer system, we show that the Q NF enhancement, due to coupling in longitudinal mode, is much greater than the enhancement in Q ext. There is a linear correlation between the Q NF and Q ext peak positions, with the Q NF peak redshifted from the Q ext peak by an average of approximately 12 nm. In the case of the multimers, Q NF spectra from individual spheres were not always identical and become dependent on the sphere location. In the longitudinal model, the center sphere has the strongest Q NF spectra. For the transverse mode, we differentiate two different scenario, transverse-Y where both electric field (E) and light propagation vector (k) are perpendicular the chain axis, and transverse-X where k is parallel to the chain axis. In transverse-Y mode, coupling leads to reduced Q NF spectra and the center sphere has the lowest Q NF intensity. In transverse-X mode, there is retardation effect from the front sphere to the back sphere. The Q NF from the front sphere is stronger than from the back sphere. In addition, due to the phase lag in k-direction, the Q NF in transverse-X can differ quite significantly from transverse-Y for large particles. All these results could be understood when one considers how electric field from induced dipoles on neighboring NPs add on or subtract from the incident E-field. These results provide new insight into the coupling properties of Au NPs.

8.
J Vet Intern Med ; 34(5): 1853-1866, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32856349

RESUMO

BACKGROUND: Metronidazole has a substantial impact on the gut microbiome. However, the recovery of the microbiome after discontinuation of administration, and the metabolic consequences of such alterations have not been investigated to date. OBJECTIVES: To describe the impact of 14-day metronidazole administration, alone or in combination with a hydrolyzed protein diet, on fecal microbiome, metabolome, bile acids (BAs), and lactate production, and on serum metabolome in healthy dogs. ANIMALS: Twenty-four healthy pet dogs. METHODS: Prospective, nonrandomized controlled study. Dogs fed various commercial diets were divided in 3 groups: control group (no intervention, G1); group receiving hydrolyzed protein diet, followed by metronidazole administration (G2); and group receiving metronidazole only (G3). Microbiome composition was evaluated with sequencing of 16S rRNA genes and quantitative polymerase chain reaction (qPCR)-based dysbiosis index. Untargeted metabolomics analysis of fecal and serum samples was performed, followed by targeted assays for fecal BAs and lactate. RESULTS: No changes were observed in G1, or G2 during diet change. Metronidazole significantly changed microbiome composition in G2 and G3, including decreases in richness (P < .001) and in key bacteria such as Fusobacteria (q < 0.001) that did not fully resolve 4 weeks after metronidazole discontinuation. Fecal dysbiosis index was significantly increased (P < .001). Those changes were accompanied by increased fecal total lactate (P < .001), and decreased secondary BAs deoxycholic acid and lithocholic acid (P < .001). CONCLUSION AND CLINICAL IMPORTANCE: Our results indicate a minimum 4-week effect of metronidazole on fecal microbiome and metabolome, supporting a cautious approach to prescription of metronidazole in dogs.


Assuntos
Metaboloma , Microbiota , Animais , Cães , Fezes , Metronidazol/farmacologia , Estudos Prospectivos , RNA Ribossômico 16S/genética
9.
Biol Rev Camb Philos Soc ; 95(5): 1479-1496, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32583608

RESUMO

Abnormal caudal regeneration, the production of additional tails through regeneration events, occurs in lepidosaurs as a result of incomplete autotomy or sufficient caudal wound. Despite being widely known to occur, documented events generally are limited to opportunistic single observations - hindering the understanding of the ecological importance of caudal regeneration. Here we compiled and reviewed a robust global database of both peer-reviewed and non-peer reviewed records of abnormal regeneration events in lepidosaurs published over the last 400 years. Using this database, we qualitatively and quantitatively assessed the occurrence and characteristics of abnormal tail regeneration among individuals, among species, and among populations. We identified 425 observations from 366 records pertaining to 175 species of lepidosaurs across 22 families from 63 different countries. At an individual level, regenerations ranged from bifurcations to hexafurcations; from normal regeneration from the original tail to multiple regenerations arising from a single point; and from growth from the distal third to the proximal third of the tail. Species showing abnormal regenerations included those with intra-vertebral, inter-vertebral or no autotomy planes, indicating that abnormal regenerations evidently occur across lepidosaurs regardless of whether the species demonstrates caudal autotomy or not. Within populations, abnormal regenerations were estimated at a mean ± SD of 2.75 ± 3.41% (range 0.1-16.7%). There is a significant lack of experimental studies to understand the potential ecological impacts of regeneration on the fitness and life history of individuals and populations. We hypothesised that abnormal regeneration may affect lepidosaurs via influencing kinematics of locomotion, restrictions in escape mechanisms, anti-predation tactics, and intra- and inter-specific signalling. Behaviourally testing these hypotheses would be an important future research direction.


Assuntos
Lagartos , Animais , Fenômenos Biomecânicos , Humanos , Locomoção , Comportamento Predatório
10.
Mol Clin Oncol ; 12(3): 191-195, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32064093

RESUMO

Circulating tumour cells (CTCs) are cancer cells of epithelial origin that are present in peripheral blood samples. ScreenCell detection of CTCs and the association with long term survival in non-small cell lung cancer (NSCLC) patients was evaluated in the present study. A total of 33 patients undergoing surgical resection for NSCLC were recruited. Patients were followed up for 5-years post-operatively. Pre-operative patient bloods samples were processed using ScreenCell. CTCs were detected in 26 (79%) patients. In patients who were positive for CTCs, a total of 9 (35%) patients succumbed to the disease, whereas in patients negative for CTCs, a total of 4 (57%) patients succumbed to the disease (P=0.29). No association was identified between positive CTCs and poorer survival (Chi-squared 1.47, P=0.23; hazard ratio, 0.42; 95% confidence interval: 0.1-1.7). The presence of CTCs detected with ScreenCell does not influence prognosis in patients with NSCLC that was operated on. The high rate of CTC detection is encouraging in supporting this technology to aid early lung cancer diagnosis.

11.
Sci Rep ; 9(1): 18717, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822746

RESUMO

Many species of lizard use caudal autotomy, the ability to self-amputate a portion of their tail, regenerated over time, as an effective anti-predation mechanism. The importance of this tactic for survival depends on the degree of predation risk. There are, however, negative trade-offs to losing a tail, such as loss of further autotomy opportunities with the regenerated tail vertebrae being replaced by a continuous cartilaginous rod. The common consensus has been that once a tail has been autotomised and regenerated it can only be autotomised proximal to the last vertebral autotomy point, as the cartilage rod lacks autotomy planes. However, anecdotal evidence suggests that although the regenerated portion of the tail is unable to autotomise, it can re-regenerate following a physical shearing event. We assessed re-regeneration in three populations of the King's skink (Egernia kingii), a large lizard endemic to south-west Western Australia and surrounding islands. We show that re-regeneration is present at an average of 17.2% across the three populations, and re-regenerated tissue can comprise up to 23.3% of an individual's total tail length. The ability to re-regenerate may minimise the costs to an individual's fitness associated with tail loss, efficiently restoring ecological functions of the tail.


Assuntos
Lagartos/fisiologia , Regeneração/fisiologia , Cauda/fisiologia , Animais , Cartilagem , Comportamento Predatório , Austrália Ocidental
12.
J Vet Emerg Crit Care (San Antonio) ; 29(6): 647-652, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31654546

RESUMO

OBJECTIVE: To identify physical exam findings, clinicopathological parameters, time to surgery, empirical antimicrobial use, and culture results that could be associated with outcome in cats with septic peritonitis (SP). DESIGN: Retrospective cohort study of cats from 2002 to 2015. SETTING: Four university teaching hospitals. ANIMALS: Eighty-three cats diagnosed with SP by cytology or culture. INTERVENTIONS: None MEASUREMENTS AND MAIN RESULTS: Fifty-eight cats survived to discharge (69.9%); 1 cat was euthanized in surgery; 20 were euthanized postoperatively; 4 cats suffered cardiac arrest after surgery. The most common etiology of SP was secondary SP due to gastrointestinal perforation (49.4%), followed by primary SP (22.3%). Mean blood glucose concentration was significantly different between survivors and nonsurvivors (P = 0.006). Cats that received appropriate empirical antibiotic therapy were 4.4 times more likely to survive than cats that did not receive appropriate antibiotics (P = 0.018). CONCLUSIONS: As previously documented, SP secondary to gastrointestinal leakage was the most common etiology. In this population, cats with a higher blood glucose concentration on presentation had a worse prognosis. Cats that received appropriate empirical antimicrobial therapy were more likely to survive.


Assuntos
Doenças do Gato/patologia , Peritonite/veterinária , Animais , Gatos , Estudos de Coortes , Feminino , Masculino , Peritonite/patologia , Prognóstico , Estudos Retrospectivos
13.
J Vet Diagn Invest ; 31(4): 645-651, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31170888

RESUMO

Pattern recognition receptors (e.g., S100A12 or S100A8/A9) hold promise as inflammatory biomarkers. We prospectively determined and compared serum S100A12 and S100A8/A9 concentrations in dogs with sepsis (n = 11) or systemic inflammatory response syndrome (SIRS; n = 8) over a 3-d period with each other, healthy controls (n = 50), and other clinical and clinicopathologic variables. Serum S100A12 and S100A8/A9 concentrations were significantly higher in dogs with sepsis or SIRS (all p < 0.05) at the time of hospital admission (day 1) compared to healthy controls, with no differences between patient groups. However, septic dogs had significantly lower serum S100A12 concentrations on day 2 and day 3 (both p < 0.05) compared to dogs with SIRS. Likewise, dogs with sepsis had significantly lower S100A8/A9 concentrations on day 2 (p < 0.05). Neither serum S100A12 nor S100A8/A9 concentrations were associated with survival to discharge. Our results suggest a differential expression of the S100/calgranulins between dogs with sepsis and those with SIRS. Serum S100A12 or S100A8/A9 concentration at the time of hospital admission did not differentiate dogs with sepsis from those with SIRS, but the trend of S100/calgranulin concentrations during the following 24-48 h may be a useful surrogate marker for differentiating sepsis from SIRS.


Assuntos
Doenças do Cão/sangue , Complexo Antígeno L1 Leucocitário/sangue , Proteína S100A12/sangue , Sepse/veterinária , Síndrome de Resposta Inflamatória Sistêmica/veterinária , Animais , Biomarcadores/sangue , Calgranulina A/sangue , Calgranulina B/sangue , Estudos de Casos e Controles , Cães , Regulação da Expressão Gênica , Masculino , Estudos Prospectivos , Sepse/sangue , Síndrome de Resposta Inflamatória Sistêmica/sangue
14.
Cancers (Basel) ; 11(3)2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30866571

RESUMO

Background: Liquid biopsies offer a promising alternative to tissue samples, providing non-invasive diagnostic approaches or serial monitoring of disease evolution. However, certain challenges remain, and the full potential of liquid biopsies has yet to be reached. Here we report several methodological approaches to interrogate liquid biopsies using circulating tumour cell (CTC) enumeration and characterisation, transcriptomics, Raman spectroscopy, and copy number instability (CNI) scores using blood samples of lung cancer (LC) patients. Methods: We choose LC; since it still is the most common cause of cancer-related mortality worldwide, and therefore there is a need for development of new non-invasive diagnostic/prognostic technologies. Changes in gene expression were assessed using RNA-seq, and in CTCs using ImageStream, an imaging flow-cytometer. CNI scores, from paired tissue/ctDNA were also explored. Raman spectroscopy was used to provide chemical fingerprints of plasma samples. Results: CTCs were detected in all LC patients (n = 10). We observed a significant increase in CTC levels in LC patients (n = 10) compared to controls (n = 21). A similar CNI was noted in the tissue and plasma of 2 patients, where higher CNI scores corresponded with poorer outcome. Significant changes in Raman spectra (carotenoid concentrations) were noted in LC patients (n = 20) compared to controls (n = 10). RNA-seq revealed differential expression of 21 genes between LC cases and controls in both LC tissue and blood samples. Conclusions: Liquid biopsies can potentially provide a more comprehensive picture of the disease compared to a single tissue biopsy. CTC enumeration is feasible and sensitive for LC patients. Molecular profiling of CTCs is also possible from total blood. CNI scores and Raman spectra require further investigation. Further work is being undertaken to explore these methods of detection in a larger LC cohort.

15.
Am J Vet Res ; 78(11): 1255-1263, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29076367

RESUMO

OBJECTIVE To characterize the maternal and fetal cardiopulmonary effects of a low-dose infusion of dexmedetomidine without a loading dose in pregnant ewes anesthetized with sevoflurane. ANIMALS 11 pregnant ewes. PROCEDURES Anesthesia was induced with propofol and maintained with sevoflurane. Ewes and fetuses were instrumented with arterial and venous catheters, and thermodilution-pulmonary arterial catheters were placed in the ewes. Baseline measurements were obtained at an end-tidal sevoflurane concentration of 3.4%, then dexmedetomidine (2 µg/kg/h, IV) was infused for 90 minutes without a loading dose. Cardiovascular and blood gas variables were measured at predetermined time points. RESULTS Dexmedetomidine infusion resulted in approximately 30% decreases in maternal systemic vascular resistance, blood pressure, and heart rate. Maternal cardiac index, oxygenation variables, and acid-base status remained unchanged, whereas pulmonary arterial pressure, pulmonary vascular resistance, and stroke volume increased, compared with baseline values. Uterine blood flow decreased by approximately 30% to 36%. Fetal heart rate and blood pressure remained unchanged, but significant increases in fetal plasma glucose and lactate concentrations were detected. CONCLUSIONS AND CLINICAL RELEVANCE Pregnant ewes receiving a combination of sevoflurane and an infusion of dexmedetomidine without a loading dose had cardiac index in acceptable ranges and maintained normoxia. This balanced anesthesia did not produce significant changes in fetal blood pressure or heart rate. However, the increase in fetal plasma lactate concentration and changes in maternal pulmonary vascular resistance and uterine blood flow require further investigation to better elucidate these effects.


Assuntos
Anestesia/veterinária , Dexmedetomidina/farmacologia , Feto/efeitos dos fármacos , Éteres Metílicos , Ovinos , Animais , Pressão Sanguínea/efeitos dos fármacos , Dexmedetomidina/administração & dosagem , Feminino , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Infusões Intravenosas , Gravidez , Propofol/administração & dosagem , Sevoflurano , Termodiluição , Resistência Vascular/efeitos dos fármacos
16.
J Vet Emerg Crit Care (San Antonio) ; 27(6): 674-683, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29068553

RESUMO

OBJECTIVE: To determine whether the concentration of serum canine alpha1 -proteinase inhibitor (cα1 -PI) has diagnostic or prognostic utility in dogs with sepsis or noninfectious systemic inflammatory response syndrome (SIRS). DESIGN: Prospective, observational study from May to December 2010. SETTING: University teaching hospital ICU. ANIMALS: Sixty-nine client-owned dogs: 19 dogs with SIRS or sepsis and 50 healthy control dogs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Serum and plasma samples were collected from dogs with SIRS or sepsis on the day of hospital admission and once on the following 2 days, and on a single day in healthy controls. Patients were assessed using the 10-parameter Acute Patient Physiologic and Laboratory Evaluation (APPLEfull ) and 5-parameter (APPLEfast ) score. Serum cα1 -PI concentrations were measured, compared among groups of dogs, and evaluated for a correlation with the concentration of serum C-reactive protein, plasma interleukin-6, tumor necrosis factor-α, the APPLE scores, and survival to discharge. Serum cα1 -PI concentrations were significantly lower in dogs with SIRS/sepsis (P < 0.001) than in healthy controls. While day 1 serum cα1 -PI concentrations did not differ between dogs with SIRS and those with sepsis (P = 0.592), septic dogs had significantly lower serum cα1 -PI concentrations on days 2 (P = 0.017) and 3 (P = 0.036) than dogs with SIRS. Serum cα1 -PI concentrations did not differ between survivors and nonsurvivors (P = 1.000), but were inversely correlated with the APPLEfull score (ρ = -0.48; P = 0.040) and plasma interleukin-6 concentrations (ρ = -0.50; P = 0.037). CONCLUSIONS: These results suggest a role of cα1 -PI as a negative acute phase protein in dogs. The concentration of serum cα1 -PI at the time of hospital admission does not have utility to identify dogs with sepsis from those with noninfectious SIRS, but may be a useful surrogate marker for early stratification of illness severity.


Assuntos
Doenças do Cão/sangue , Sepse/veterinária , Síndrome de Resposta Inflamatória Sistêmica/veterinária , alfa 1-Antitripsina/sangue , Animais , Biomarcadores , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Cães , Feminino , Humanos , Interleucina-6/sangue , Masculino , Peptídeo Hidrolases , Prognóstico , Estudos Prospectivos , Sepse/sangue , Síndrome de Resposta Inflamatória Sistêmica/sangue , Fator de Necrose Tumoral alfa/sangue
17.
Interact Cardiovasc Thorac Surg ; 24(5): 796-798, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28329256

RESUMO

A best evidence topic in cardiovascular surgery was written according to a structured protocol. The question addressed was whether the thoracic aorta is a safe site for the proximal anastomosis when bypassing the mesenteric arteries in patients with chronic mesenteric ischaemia. Five articles reported the use of the thoracic aorta as the site of proximal anastomosis in 35 patients with chronic mesenteric ischaemia. All of these studies were retrospective case reports or case series. The ascending aorta was the site for the proximal anastomosis in 7 patients with the descending thoracic aorta being used in the other 28 patients. The ascending aorta was used when there was disease of the descending thoracic aorta. Out of the 35 patients there was only 1 perioperative death (3%). Rates of graft patency and freedom from recurrent symptoms were excellent. The published literature supports the use of the thoracic aorta as an option for the site of the proximal anastomosis when bypass from elsewhere is not possible.


Assuntos
Aorta Torácica/cirurgia , Artérias Mesentéricas/cirurgia , Isquemia Mesentérica/cirurgia , Procedimentos Cirúrgicos Vasculares/métodos , Idoso , Anastomose Cirúrgica/métodos , Angiografia , Doença Crônica , Humanos , Masculino , Isquemia Mesentérica/diagnóstico , Estudos Retrospectivos , Resultado do Tratamento
18.
Vet Med (Auckl) ; 8: 21-26, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30050851

RESUMO

A hospital-based, prospective cross-sectional study was used to compare kaolin-activated thromboelastography (TEG) parameters with traditional coagulation tests in 29 hospitalized dogs. Cases were included if the attending clinician requested coagulation testing. Blood was obtained from each dog and coagulation (prothrombin time, partial thromboplastin time, antithrombin activity, d-dimer concentration, and fibrinogen concentration) and TEG analyses were performed. Hematocrit (Hct) was also measured. Traditional coagulation results were evaluated for correlation with those from kaolin-activated TEG. Spearman's correlation was used to calculate correlation coefficients. Fibrinogen was positively correlated with maximum amplitude (Pearson r=0.72, P<0.001) and global clot strength (Pearson r=0.72, P<0.001). There was no correlation between any of the remaining coagulation variables, TEG parameters, or Hct. Results of kaolin-activated TEG and traditional coagulation tests are not interchangeable means of monitoring coagulation derangements in this intensive care unit patient population. Determination of a true outcome measure is necessary to establish TEG's clinical relevance to veterinary medicine.

19.
Anticancer Res ; 37(1): 169-173, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28011487

RESUMO

BACKGROUND: Detection of circulating tumour cells (CTCs) in the peripheral blood of lung cancer patients may predict survival. Various platforms exist that allow capture of these cells for further analysis; little work however, has been done with the ScreenCell device, an antibody-independent CTC platform. The aim of our study was to evaluate the ScreenCell device for detection of CTCs in lung cancer patients and to establish correlations of these findings with survival. MATERIALS AND METHODS: Twenty-three patients, nine males, and fourteen females, underwent surgical treatment from February to May 2014 for non-small cell lung cancer. Thirteen patients had adenocarcinoma and ten squamous cell carcinoma, while eight were at an early stage (I-II) and five at a later stage (III-IV). Blood samples were obtained prior to surgery and following filtration through the ScreenCell device, were independently reviewed by 2 consultant pathologists. RESULTS: The pathologists were able to independently identify CTCs in 78.3% (N=18) and 73.9% (N=17) of the cases examined, with overall 80.6% in early stages compared to 60.0% in late stages. The median survival times of positive vs. negative for CTC patients were 1011 and 711 days respectively, with a survival percentage rate of 77.8% and 60% in positive and negative CTC cohorts respectively. CONCLUSION: The results of this study suggest that the presence of CTCs analyzed by ScreenCell did not necessarily lead to a poorer prognosis in patients with lung cancer after curative surgery.


Assuntos
Adenocarcinoma/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Células Neoplásicas Circulantes/patologia , Idoso , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico
20.
Ann Vasc Surg ; 39: 292.e9-292.e15, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27908818

RESUMO

Chronic mesenteric ischemia (CMI) is a rare disorder caused by severe stenosis of the mesenteric arterial supply that results in postprandial pain and weight loss. Treatment options are surgical or endovascular. Surgical bypass can be performed in an antegrade fashion from the supraceliac abdominal aorta (AA) or the distal descending thoracic aorta or in a retrograde fashion from the infrarenal aorta or the common iliac artery. However, in some patients with disease of the descending thoracic aorta or the AA, another site for the proximal anastomosis needs to be found. In this article, we report the case of a 69-year-old man with a thoracoabdominal aortic aneurysm and CMI in whom we performed bypass grafts to the hepatic and superior mesenteric arteries using the ascending aorta as the site for the proximal anastomoses via a median sternolaparotomy. In addition, we performed a literature review of all similar cases and provide an analysis of this technique and an assessment of the success rates.


Assuntos
Aorta/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Implante de Prótese Vascular/métodos , Artéria Hepática/cirurgia , Artéria Mesentérica Superior/cirurgia , Isquemia Mesentérica/cirurgia , Veia Safena/transplante , Idoso , Anastomose Cirúrgica , Aorta/diagnóstico por imagem , Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aortografia/métodos , Doença Crônica , Angiografia por Tomografia Computadorizada , Artéria Hepática/diagnóstico por imagem , Humanos , Masculino , Artéria Mesentérica Superior/diagnóstico por imagem , Isquemia Mesentérica/complicações , Isquemia Mesentérica/diagnóstico por imagem , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA