Optical polarization characteristics and light extraction behavior of deep-ultraviolet LED flip-chip with full-spatial omnidirectional reflector system

Optical polarization characteristics and light extraction behavior of deep-ultraviolet (DUV) light-emitting diode (LED) flip-chip with full-spatial omnidirectional reflector (FSODR) have been investigated. FSODR is fabricated to be simultaneously covered on the whole flip-chip, except the sapphire surface. It is found that the FSODR greatly enhance both transverse-electric (TE) and transverse-magnetic (TM) mode light extraction at every space angle, resulting in total enhancement of 73.1% and 79.8%, respectively. Moreover, the four individual ODR structures separated from FSODR, which are covered on the surface of n-AlGaN, the interface of p-GaN/p-AlGaN, the sidewall of mesa and the sidewall of n-AlGaN/AlN, respectively, show considerably different optical polarization characteristics and extraction behaviors between each other. The achievements of FSODR cannot be obtained by any separated ODR, and all of the individual ODRs can contribute to the FSODR. Especially, the synergy effect of TM extraction behavior obviously exists in FSODR. As a result, the light extraction efficiency (LEE) enhancement of FSODR is approximately 60% at a high current density of 140A/cm². This study is significant for understanding and modulating the extraction behavior of polarized light to realize high efficiency AlGaN-based DUV LEDs.

Advantages of AlGaN-based deep-ultraviolet light-emitting diodes with an Al-composition graded quantum barrier

AlGaN-based deep-ultraviolet light-emitting diodes (DUV LEDs) still suffer from poor quantum efficiency and low optical power. In this work, we proposed a DUV LED structure that includes five unique Al_xGa_1-xN quantum barriers (QBs); Each QB has a linear-increment of Al composition by 0.03 along the growth direction, unlike those commonly used flat QBs in conventional LEDs. As a result, the electron and hole concentration in the active region was considerably increased, attributing to the success of the electron blocking effect and enhanced hole injection efficiency. Importantly, the optical power was remarkably improved by 65.83% at the injection current of 60 mA. After in-depth device optimization, we found that a relatively thinner graded QB layer could further boost the LED performance because of the increased carrier concentrations and enhanced electron and hole wave function overlap in the QW, triggering a much higher radiative recombination efficiency. Hence, the proposed graded QBs, which have a continuous increment of Al composition along the growth direction, provide us with an effective solution to boost light output power in the pursuit of high-performance DUV emitters.

[Establishment of a nomogram model for predicting lymph node metastasis in patients with cN0 gastric cancer based on combination of preoperative C-reactive protein/albumin ratio]

Objective: To investigate the relationship between systemic inflammatory markers such as neutrophil/lymphocyte ratio (NLR) and C-reactive protein/albumin ratio (CAR), and lymph node metastasis in patients with cN0 gastric cancer. To establish a nomogram model to predict the risk of lymph node metastasis in patients with cN0 gastric cancer. Methods: The preoperative systemic inflammatory markers and clinical data of 134 patients with cN0 gastric cancer were retrospectively analyzed, and these markers of patients with negative (pN0) or positive (pN+ ) lymph node metastasis in postoperative pathological diagnosis were compared. The receiver operating characteristic (ROC) curve was used to evaluate the predictive effect of preoperative systemic inflammatory markers on lymph node metastasis. The influencing factors for lymph node metastasis were assessed by univariate analysis and multivariate logistic regression analysis. A nomogram subsequently established by R software was validated by Bootstrap resampling as internal validation. Results: Compared with pN0 group, NE (P=0.022), CRP (P<0.001), NLR (P<0.001), PLR (P=0.003) and CAR (P<0.001) were higher, LY (P=0.003) and Alb (P=0.042) were lower in pN+ group. ROC curve analysis showed that the area under the curve (AUC) of postoperative pathological lymph node metastasis in patients with cN0 gastric cancer diagnosed by NLR, PLR and CAR were 0.687, 0.651 and 0.694, respectively, and the best cutoff values were 2.12, 113.59 and 0.02, respectively. The corresponding sensitivity and specificity were 62.9% and 72.2%, 77.4% and 48.6%, 74.2% and 58.3%, respectively. Univariate analysis showed that tumor size, depth of invasion, NLR, PLR and CAR were associated with lymph node metastasis in cN0 gastric cancer patients (all P<0.05). Multivariate analysis showed that depth of invasion, NLR and CAR were independent influencing factors of lymph node metastasis in patients with cN0 gastric cancer. OR were 8.084, 3.540 and 3.092, respectively (all P<0.05). The C-index of the nomogram model was 0.847 (95% CI: 0.782-0.915). The predicting calibration curve was properly fit with the ideal curve in calibration chart. Conclusion: Combination of NLR and CAR to establish a nomogram model has a good consistency and can accurately predict the risk of lymph node metastasis in patients with cN0 gastric cancer.

Bio-Inspired Flexible Fluoropolymer Film for All-Mode Light Extraction Enhancement

Enhancing the light extraction efficiency is a prevalent but vital challenge for most solid-state lighting technologies, especially for deep ultraviolet light-emitting diodes (DUV-LEDs). In this paper, inspired by the microstructure of the butterfly's eye, we propose and fabricate a flexible fluoropolymer film (FFP film) to tackle this issue for all-mode, full-wavelength light extraction enhancement for most solid-state lighting technologies compatibly. The experimental results demonstrate that compared with one mounted with a smooth FFP film, the light output power of DUV-LED is enhanced up to 26.7% by mounting the FFP film with 325 nm radius nanocones at a driving current of 200 mA. Importantly, thanks to the super-flexible feature of the FFP film, it can both cover the top surface and sidewalls of the DUV-LED chip, leading to the improvement of transverse electric and transverse magnetic mode light extraction by 20.5 and 21.8%, respectively. Finite element analysis (FEA) simulations of the electric field distribution of DUV-LEDs with the FFP film reveal the underlying physics. The present strategy is proposed from the view of the packaging level, which is cost-effective, able to be manufactured at a large scale, and compatible with the solid-state lighting technologies.

Three-dimensional damage morphologies of thermomechanically deformed sintered nanosilver die attachments for power electronics modules

A time-lapse study of thermomechanical fatigue damage has been undertaken using three-dimensional X-ray computer tomography. Morphologies were extracted from tomography data and integrated with data from microscopy modalities at different resolution levels. This enables contextualization of some of the fine-scale properties which underpin the large-scale damage observed via tomography. Lateral views of crack development are presented, which show networks analogous to mud-cracks. Crack fronts which develop in the most porous regions within the sintered attachment layer travel across the boundary into the copper substrate. The propagation characteristics of these cracks within the substrate are analysed. Evidence is provided of heterogeneous densification within the sintered joint under power cycling, and this is shown to play a major role in driving the initiation and propagation of the cracks. Examination of the texture (differing levels of X-ray absorption) of virtual cross-sectional images reveals the origins of the nonuniformity of densification. Finally, cracks within the sintered joint are shown to have a negligible impact on the conduction pathway of the joint due to their aspect ratio and orientation with respect to the assembly. LAY DESCRIPTION: This paper concerns the use of three-dimensional (3D) X-ray tomography, a nondestructive technique, to perform cradle-to-grave studies of sintered nanosilver die-attachments under operation. Sintered nanosilver die-attachments have been proposed as a more reliable and environmentally friendly alternative to solder alloy joints for emerging power electronics module designs. However, their degradation mechanisms are not as well understood. This same sample-study is about observing how the fine-scale structure of a sintered attachment evolves and degrades over time. Using 3D tomography affords otherwise infeasible perspectives, such as virtual cross-sections in the lateral plane of the attachment. These perspectives provide qualitative information which elucidates the degradation mechanisms. They demonstrate, for example, that the structure of the sintered attachment densifies under operation, and a consequence of this is the formation of shrinkage cracks in the most porous regions, much like mud-cracks. Other imaging techniques (metallographic etching and scanning electron microscopy) have been used in correlation with 3D renderings of these cracks to analyse their propagation and reveal their relationship both with the internal structure of the sintered attachment itself, and the structure of the substrate to which it is joined. It is shown that the cracks develop within the sintered attachment layer and eventually cross over into the substrate. A comparison of two sintered attachments with contrasting bulk porosities allows the effect of initial bond quality on crack development to be examined.

BRAF inhibitors: efficacious and tolerable in BRAF-mutant acral and mucosal melanoma

BRAF inhibitors substantially have impressive clinical efficacy in cutaneous melanoma. However, their role in acral and mucosal melanoma remains unclear. Records were reviewed of patients with metastatic or unresectable BRAF-mutant acral and mucosal melanoma hospitalized and administrated BRAF inhibitors during January 2011 and March 2016. Clinical data were collected to determine PFS, ORR, DCR, OS, and safety. Among 28 acral and 12 mucosal melanoma patients treated with BRAF inhibitors, median PFS were 3.6 (95%CI 3.0-6.4) and 4.4 (95%CI 0.8-12.7) months, median OS were 6.2 (95%CI 6.1-12.1) and 8.2 (95%CI 6.6-19.9) months; ORRs were 38.1% and 20.0%, DCRs were 81.0% and 70.0% in acral and mucosal melanoma, respectively. BRAF inhibitors were well tolerated. The most common adverse effects (AEs) were cutaneous and hematological. Grade 3/4 AEs were relatively rare. In conclusion, BRAF inhibitors have acceptable efficacy and good tolerance in BRAF mutant acral and mucosal melanoma.

Ultraviolet polarized light emitting and detecting dual-functioning device based on nonpolar n-ZnO/i-ZnO/p-AlGaN heterojunction

We report on the demonstration of a 386 nm light emission and detection dual-functioning device based on nonpolar a-plane n-ZnO/i-ZnO/p-Al_0.1Ga_0.9N heterojunction under both forward and reverse bias. The electroluminescence intensity under reverse bias is significantly stronger than that under forward bias, facilitated by carrier tunneling when the valence band of p-AlGaN aligns with the conduction band of i-ZnO under reverse bias. Also amid reverse bias, the photodetection was observed and applied in a duplex optical communication device. Optical polarization of the light emission is studied for potential polarization-sensitive device applications. The proposed device provides an important pathway for the multifunctional devices operating in a UV spectrum.

MiR-34a regulates cell apoptosis after myocardial infarction in rats through the Wnt/β-catenin signaling pathway

OBJECTIVE

To explore the molecular mechanism of micro ribonucleic acid-34a (miR-34a) in promoting the apoptosis of myocardial cells in the rat model of myocardial infarction (MI).

MATERIALS AND METHODS

Sprague-Dawley (SD) rats were ligated with a left anterior descending branch to construct the MI model. The rats were randomly divided into four groups: sham operation group (Sham group), MI group, MI + miR-34a inhibitor group (MI + miR-34a antagomir group) and MI + miR-34a inhibitor negative control group (MI + antagomir NC group). Echocardiography (ECG) and magnetic resonance imaging (MRI) were adopted to detect the ejection fraction [EF (%)] and fraction shortening [FS (%)] of SD rats. Polymerase chain reaction (PCR) and Western blotting were used to detect expression levels of the apoptotic marker Caspase-3 and genes in Wnt/β-catenin signaling pathway. Hematoxylin and eosin (H&E) staining was applied to detect cardiac injury. In in vitro experiments, the rat-derived myocardial cell line H9C2 was selected to simulate myocardial ischemia and hypoxia at the time of MI with an anoxic and serum-free injury model. C59, the Wnt/β-catenin signaling pathway inhibitor was applied in MI + miR-34a antagomir + C59 group, and the effect of miR-34a on the apoptosis of myocardial cells through regulating the Wnt/β-catenin pathway was measured with Real-Time quantitative PCR (qPCR) and 3-(4,5)-dimethylthiazol(-z-y1)-3,5-diphenyltetrazolium bromide (MTT) cell activity detection kits, respectively.

RESULTS

It was found that after miR-34a antagomir reversed FS (%) and EF (%) in MI rats, the messenger RNA (mRNA) and protein levels of Caspase-3 in Sham group and MI + miR-34a antagomir group were significantly lower than those in the MI group (p < 0.05), indicating that the addition of miR-34a antagomir inhibited myocardial cell apoptosis after infarction, while the mRNA and protein levels of Wnt/β-catenin were both higher than those in the MI group. Besides, H&E staining proved that miR-34a reversed the myocardial injury after MI. Similarly, in vitro experiments showed that, compared with those in Hypoxia group, the level of Caspase-3 decreased in Hypoxia + miR-34a inhibitor group and Sham group, while the apoptosis level in Hypoxia + miR-34a inhibitor + C59 group increased (p < 0.05). The results of the MTT assay were consistent with those of PCR. MiR-34a affects myocardial cell apoptosis by regulating the activation and inactivation of the Wnt/β-catenin signaling pathway.

The clinical significance of perineural invasion in patients with de novo metastatic prostate cancer

BACKGROUND

The clinical value of perineural invasion (PNI) in patients with localized prostate cancer (PCa) is widely explored. However, its role in metastatic PCa (mPCa) remains unknown.

OBJECTIVES

We aim to investigate the clinical significance of PNI in patients with mPCa.

MATERIALS AND METHODS

Data of 515 mPCa patients between 2012 and 2018 were retrospectively studied. PNI and its intensity were identified by prostate biopsy. The prognostic value of PNI was evaluated by Kaplan-Meier curves and Cox proportional-hazards model.

RESULTS

Perineural invasion was detected in 170/515 (33.0%) cases. Among them 73/170 (42.9%) and 97/170 (57.1%) harbored unifocal PNI (uni-PNI) and multifocal PNI (multi-PNI), respectively. Compared to patients without PNI, those with PNI had statistically shorter castration-resistant PCa-free survival (CFS) and numerically shorter overall survival (OS) (mCFS: 15.4- vs. 18.5-Mo, p = 0.015; mOS: 63.8- vs. 71.4-Mo, p = 0.108). Patients harboring multi-PNI were associated with poorer clinical outcomes than those with uni-PNI (mCFS: 12.4- vs. 18.0-Mo, p = 0.040; mOS: 39.7-Mo vs. NR, p = 0.018) or those without PNI (mCFS: 12.4- vs. 18.5-Mo, p = 0.002; mOS: 39.7- vs. 71.4-Mo, p = 0.002). Totally, neither uni-PNI nor multi-PNI was an independent risk factor impacting survival outcomes in multivariate analyses. While remarkably, for patients with favorable/intermediate-risk mPCa, multi-PNI was an independent adverse prognosticator for both CFS and OS (CFS: HR: 1.705, 95% CI: 1.029-2.825, p = 0.038; OS: HR: 3.294, 95% CI: 1.464-7.413, p = 0.004).

DISCUSSION AND CONCLUSION

This study filled the blank of the clinical significance of PNI in mPCa. We found that multi-PNI could distinguish men with relatively poor prognosis from patients initially regarded as with favorable survival outcomes by other prognosticators, and thus, avoid disease underestimation in this group of patients. Our finding would help physicians have a deeper understanding of the heterogeneity of mPCa and make better individualized therapeutic strategy.

Association of Fruit and Vegetable Intake and Frailty among Chinese Elders: A Cross-Sectional Study in Three Cities

OBJECTIVES

To examine the association of FVI and frailty in Chinese elders.

DESIGN

A sectional study was conducted in three cities (Shanghai, Zhengzhou, and Baoji) in China from June 2017 to June 2018.

PARTICIPANTS

A total of 5699 participants from 49 districts were included in the current study by two-stage sampling methods.

MEASUREMENTS

Frailty was measured by a validated Chinese version of the FRAIL scale. FVI per day was measured by two single questions.

RESULTS

The sample proportion with sufficient fruit intake was 36.7%, and 44.7% reported sufficient vegetable intake. The sample proportions that were robust, pre-frail, and frail were 43.6%, 38.3%, and 18.1%, respectively. Compared with low FVI, after including covariates, the odds ratio (OR) of frailty was 0.84 (95% CI: 0.73-0.97) for moderate fruit intake and 0.81 (95% CI: 0.70-0.94) for enough fruit intake; the OR of frailty was 0.83 (95% CI: 0.68-0.91) for moderate vegetable intake and 0.77 (95% CI: 0.64-0.93) for enough vegetable intake.

CONCLUSION

High FVI was negatively associated with the OR of frailty in Chinese elders. This finding implies it is important to promote FVI among adults to prevent frailty.

Fast growth of high quality AlN films on sapphire using a dislocation filtering layer for ultraviolet light-emitting diodes

A simple strategy for the mass production of high-quality AlN epilayers on flat sapphire by utilizing a dislocation filtering layer.

Immune Tolerance Induced by Decitabine Combined With Multiple Allogeneic Bone Marrow Mononuclear Cell Infusion

OBJECTIVE

The aim of our study was to investigate the strategy of immune tolerance induced by the demethylating drug decitabine (DAC) combined with multiple allogeneic bone marrow mononuclear cell (BMMNC) infusions.

METHODS

An animal model with C57BL/6 mice as recipients and a BALB/c mouse as the donor was established. C57BL/6 mice were randomly divided into the following groups: DAC, BMMNC, DAC+BMMNC, and the control groups. Mice in the DAC and DAC+BMMNC groups were given DAC (5 μg/kg) on days 1, 2, 7, 8, 13, and 14. On experimental days 3, 9, and 15, BMMNCs (5 × 10⁶/mouse/time) from BALB/c mice were infused into mice of the BMMNC and DAC+BMMNC groups. One-way mixed lymphocyte reaction (MLR), interleukin-2 reverse test, and in vitro adoptive transfer experiments were performed. The ratio of regulatory T cells in splenocytes, chimera detection, and median survival time of skin grafts were recorded.

RESULTS

MLR showed that the stimulation index of the DAC+BMMNC group was significantly lower compared with the other 3 groups (P < .01), but still showed a strong proliferative response to the third-party unrelated donor KM mice, with no significant difference compared with the other 3 groups. The MLR low reactivity of the DAC+BMMNC group could be reversed by exogenous interleukin-2. After adding an equal amount of splenocytes from a C57BL/6 mouse in the DAC+BMMNC group, MLR of control group significantly decreased (P < .05). Flow cytometry showed the ratio of regulatory T cells in splenocytes from DAC and DAC+BMMNC groups was significantly higher than that from the BMMNC and control groups (P < .05). Chimeric rate of the DAC+BMMNC (60%) group was significantly higher than that of the BMMNC group (30%). Moreover, survival time of skin grafts in the DAC+BMMNC group was significantly longer than that in the other 3 groups (P < .001). No death or graft-vs-host disease was observed.

CONCLUSION

DAC combined with multiple allogeneic BMMNC infusion could successfully induce specific immune tolerance in mice, which may provide some new strategies to improve immune tolerance after organ transplant.

Evolutionary divergence of mitochondrial genomes in two Tetranychus species distributed across different climates

There is increasing evidence that mitochondrial genomes (mitogenomes) can be under selection, whereas the selective regimes shaping mitogenome evolution remain largely unclear. To test for mitogenome evolution in relation to the climate adaptation, we explored mtDNA variation in two spider mite (Tetranychus) species that distribute across different climates. We sequenced 26 complete mitogenomes of Tetranychus truncates, which occurs in both warm and cold regions, and nine complete mitogenomes of Tetranychus pueraricola, which is restricted to warm regions. Patterns of evolution in the two species' mitogenomes were compared through a series of d_N /d_S methods and physicochemical profiles of amino acid replacements. We found that: (1) the mitogenomes of both species were under widespread purifying selection; (2) elevated directional adaptive selection was observed in the T. truncatus mitogenome, perhaps linked to the cold climates adaptation of T. truncatus; and (3) the strength of selection varied across genes, and diversifying positive selection detected on ND4 and ATP6 pointed to their crucial roles during adaptation to different climatic conditions. This study gained insight into the mitogenome evolution in relation to the climate adaptation.

New microsatellites revealed strong gene flow among populations of a new outbreak pest, Athetis lepigone (Möschler)

Athetis lepigone (Möschler) (Lepidoptera: Noctuidae) is a new outbreak pest in China. Consequently, it is unclear whether the emergence and spread of the outbreak of this pest are triggered by rapid in situ population size increases in each outbreak area, or by immigrants from a potential source area in China. In order to explore the outbreak process of this pest through a population genetics approach, we developed ten novel polymorphic expressed sequence tags (EST)-derived microsatellites. These new microsatellites had moderately high levels of polymorphism in the tested population. The number of alleles per locus ranged from 3 to 19, with an average of 8.6, and the expected heterozygosity ranged from 0.269 to 0.783. A preliminary population genetic analysis using these new microsatellites revealed a lack of population genetic structure in natural populations of A. lepigone. The estimates of recent migration rate revealed strong gene flow among populations. In conclusion, our study developed the first set of EST-microsatellite markers and shed a new light on the population genetic structure of this pest in China.

Etiology and Pathogenesis of Hemifacial Microsomia

Hemifacial microsomia (HFM) is a common congenital malformation of the craniofacial region. There are 3 possible pathogenic models of HFM—vascular abnormality and hemorrhage in the craniofacial region, damage to Meckel’s cartilage, and the abnormal development of cranial neural crest cells—and the most plausible hypothesis is the vascular abnormality and hemorrhage model. These 3 models are interrelated, and none of them is completely concordant with all the variable manifestations of HFM. External environmental factors (e.g., thalidomide, triazene, retinoic acid, and vasoactive medications), maternal intrinsic factors (e.g., maternal diabetes), and genetic factors (e.g., the recently reported mutations in OTX2, PLCD3, and MYT1) may lead to HFM through ≥1 of these pathogenic processes. Whole genome sequencing to identify additional pathogenic variants, biological functional studies to understand the exact molecular mechanisms, and additional animal model and clinical studies with large stratified samples to elucidate the pathogenesis of HFM will be necessary. Small-molecule drugs, as well as CRISPR/CAS9-based genetic interventions, for the prevention and treatment of HFM may also be a future research hotspot.

[Impact of first-line chemotherapy on renal function in patients with advanced upper tract urothelial carcinoma]

Objective: To observe the impact of first-line chemotherapy on renal function in patients with unresectable/metastatic upper tract urothelial carcinoma(UTUC). Methods: A total of 222 (130 males and 92 females) unresectable/metastatic upper tract urothelial carcinoma patients were included in the study between January 2005 and May 2017, with age of 29 to 87 (62.4±10.1) years old. The serum creatinine level and estimated glomerular filtration rate (eGFR) were compared before and after first-line chemotherapy. And predictive factors for decreased renal function were analyzed in logistic regression model. Results: After the first-line chemotherapy, the average serum creatinine level increased, with a median changing value of 1.5 μmol/L. Howerver, the eGFR improved, with a median changing value of 0.5 ml·min^-1· (1.73 m²)^-1, but the differences were not statistically significant (all P>0.05). In 149 patients who were treated with cisplatin-based chemotherapy, the average serum creatinine level increased by 1.31 μmol/L and eGFR improved by 0.14 ml·min^-1·(1.73 m²)^-1, but the differences were not statistically significant (P>0.05). In multivariate logistic regression model, age more than and equal to 60 years old (OR=0.88, P=0.745) and cisplatin-based chemotherapy (OR=0.95, P=0.893) did not increase the risk of renal dysfunction after first-line chemotherapy. If the time interval between surgery and first-line chemotherapy was more than 1 year, the risk of renal dysfunction due to chemotherapy decreased (OR=0.54, P=0.196). Eastern Cooperative Oncology Group Performance Status (ECOG PS) Scale≥1 (OR=1.81, P=0.131), anemia before treatment (OR=1.14, P=0.764), the cycles of first-line chemotherapy (OR=1.41, P=0.398) may lead to increase the risk of renal dysfunction, but the differences were not statistically significant. However in the patients who accepted nephrectomy, the risk of renal dysfunction after chemotherapy increased, but the difference was still not statistically significant (OR=3.06, P=0.089). Conclusions: First-line chemotherapy, especially the cisplatin-based regimen, had no significant impact on renal function in the patients with UTUC. Nephrectomy maybe a predictive risk factor for decreased renal function after chemotherapy. Adequate assessment of renal function before treatment, hydration and close monitoring during chemotherapy can effectively protect renal function of the patients.

A new method for determining levels of sedation in dogs: A pilot study with propofol and a novel neuroactive steroid anesthetic

BACKGROUND

Different levels of consciousness are required in order to perform different medical procedures. Sedation scales established to objectively define various levels of sedation in humans have not been thoroughly characterized in non-human species. Postural changes in rats or dogs are useful as gross measures of sedation but are inadequate for quantitative assessment since graded levels of sedation are difficult to delineate and obscured by movement abnormalities.

NEW METHOD

A new canine sedation scoring (CSS) method was developed based on the modified observer's assessment of alertness and sedation score (MOAA/S) used in humans. The method employed a combination of physical, auditory and somatosensory stimuli of increasing intensity. Cardiovascular, respiratory, and a neurophysiological measure of sedation (bispectral index: BIS) data were recorded. Validation studies were performed following intravenous loading and constant rate infusion of propofol or a novel synthetic neuroactive steroid (SGE-746).

RESULTS

Four levels of consciousness were identified: 1) Awake, 2) Moderate Sedation (MS), 3) Deep Sedation (DS) and 4) General Anesthesia (GA). Cardiorespiratory measurements obtained after bolus administration of propofol and SGE-746 and at the end of each CRI remained within normal limits. Canine sedation scores correlated with BIS for SGE-746. SGE-746 exhibited a more gradual exposure-response relationship than propofol. Larger increases in the plasma concentration from awake values were required to achieve different levels of sedation with SGE-746 compared to propofol.

COMPARISON WITH EXISTING METHODS

No other canine sedation scoring methods are widely accepted.

CONCLUSION

A CSS method, based on the human MOAA/S scale defined four levels of consciousness in dogs and provided better resolution of sedation depth than BIS alone.