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The wellbeing of paediatric intensive care unit (PICU) staff members influences their engagement with work and the quality of care they provide to patients. Baseline burnout measures in research provide inconclusive evidence of the determinants of burnout and how to target interventions to promote staff wellbeing.The objectives of this study were to determine the prevalence of burnout using the Maslach Burnout Inventory (MBI) burnout-engagement workplace profiles in a sample of Australian PICU staff and investigate associations between demographic characteristics, meaningful work, satisfaction with life, and psychological distress on burnout.A cross-sectional survey was administered to a multidisciplinary sample of PICU staff (target n = 464) from three tertiary paediatric hospitals in Australia. The survey tool was comprised of the MBI, Work and Meaning Inventory, Satisfaction with Life Scale, Kessler Psychological Distress Scale, and demographic questions. Hierarchical multiple regressions examined the relationships between burnout and these variables of interest.A sample of 258 participants (56%) completed the survey. For most respondents, burnout was scored as a low to moderate risk, with over half the participants scoring low risk for emotional exhaustion (EE) (56%) and depersonalisation (DP) (54%). Personal accomplishment (PA) was more evenly distributed (range of burnout risk: low, 32%; moderate, 32%; high, 36%). MBI scores were classified using the burnout-engaged workplace profile system, identifying low levels of burnout (8% burnout, 3% disengaged, 21% overextended, 29% ineffective, and 39% engaged). Psychological distress significantly increased burnout risk across all three dimensions EE (β = 0.253, p 0.001), DP (β = 0.145, p 0.05), and PA (β = -0.13, p 0.05), and being aged between 41 and 55 years was protective of depersonalisation (β = -0.214, p 0.05).Utilising MBI workplace profiles, this study has built upon the demand for a more comprehensive assessment of burnout. Research that helps improve our understanding of contributory factors to burnout and wellbeing will inform the development of effective interventions that promote wellbeing of staff.

We report on the observation of vortex instabilities in the wake of a tidal turbine undergoing axially oscillating inflow, using unsteady RANS simulations. Unsteady inflow causes the turbine blades to shed vorticity of time-varying strength into the wake, which in turn leads to a spatial variation in wake vortex strength, such that the vorticity of adjacent returning wake segments can differ. This spatial variation triggers the instability of tip vortices, the characteristics of which are shown to be governed by the ’frequency ratio’ ω/ΩNB (where ω is harmonic inflow frequency, Ω is turbine rotational frequency and NB is the number of blades). If ω/ΩNB = m, where m is an integer, the wake is stable. If ω/ΩNB takes the form of 1/m or (m − 1)/m, however, m adjacent tip vortices start leapflogging and merging into a larger vortex, creating a new vortex street with a lower spatial frequency. At other frequency ratios, the tip vortices exhibit more irregular deformation, suggesting a possible early breakdown into turbulence. This has implications for both wind and tidal farm design, where the interaction of downstream turbines with the wakes of upstream turbines is an important consideration.

Background: Despite high morbidity and mortality among people who use drugs (PWUD) in rural America, most research is conducted within urban areas. We describe influencing factors, motivations, and barriers to research participation and retention among rural PWUD. Methods: We recruited 255 eligible participants from community outreach and community-based, epidemiologic research cohorts from April-July 2019 to participate in a descriptive cross-sectional study. Eligible participants reported opioid or injection drug use to get high within 30 days and resided in high-needs rural counties in Oregon, Kentucky, and Ohio. We aggregated response rankings to identify salient influences, motivations, and barriers. We estimated prevalence ratios to assess for gender, preferred drug use, and geographic differences using log-binomial models.Results: Most participants were male (55%) and recently injected methamphetamine (61%) and/or heroin (57%). The primary influential factors for research participation are confidentiality, amount of financial compensation, and time required. Primary motivations for participation include financial compensation, free HIV/HCV testing, and linkage with resources. Changed or false participant contact information and transportation are principal barriers to retention. Respondents who prefer methamphetamines over heroin are more influenced by why their information is collected and how it is used (PR=1.12; 95%CI:1.00, 1.26). Knowing and wanting to help the research team are motivations for participation among Oregon participants (PR=2.12; 95%CI:1.51, 2.99) and females (PR=1.57; 95%CI:1.09, 2.26).Conclusions: Beyond financial compensation, researchers should emphasize confidentiality, offer testing and linkage with care, use several contact methods, aid transportation, and accommodate demographic differences to improve research participation and retention among rural PWUD.

Because of the poor prognosis and of oral mucosal melanoma, and patients' short survival, large, randomised, clinical studies are difficult. We have investigated its demographic characteristics and analysed the effect of treatment, resection margins, and metastases on survival. We recorded age, sex, site of primary tumour, and types of treatment, survival, and metastases in 74 patients treated at the Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital. Survival was analysed based on bony invasion, depth of invasion, and resection margins, and we found that it varied depending on the primary site (p=0.002), and declined with liver (p=0.001) or brain (p=0.033) metastases. The two-year survival according to the primary site was as follows: palate 85% (n=32), anterior maxillary gingiva 53% (n=13), mandible 58% (n=13), and posterior maxillary gingival 74% (n=10) and buccal mucosa 50% (n=4). The two-year survival was 34% (n=8) in patients with liver metastases and 23% (n=7) in patients with brain metastases. In cases of bony invasion (p=0.005), depth of invasion (p=0.042), unclear resection margin (p=0.023), or higher T stages (p=0.009), the survival declined considerably. Neck dissection did not affect survival (p=0.343). Survival of the patients given chemotherapy was significantly lower (p=0.013) and the two-year survival was 54.0%. The patients given radiotherapy showed no significant difference in survival compared with those not given radiotherapy (p=0.107). In conclusion, primary site, bony invasion, resection margins, depth of invasion and systemic metastases were critical to predict prognosis and selection of treatment of oral mucosal melanoma.

A fast-response five-hole probe has been developed for the measurement of turbulent flow structures in tidal channels. Such measurements are vital for accurate prediction of unsteady loads on tidal turbines. Existing field-based velocimeters are unable to capture the required range of frequencies or are too expensive to profile the variation of turbulence across a typical tidal power site, and thus the data they provide is inadequate for turbine design. This work adapts an established measurement technique from the turbomachinery community – a fast-response, multi-hole pneumatic probe – to achieve a low cost device which covers the required frequency range for tidal turbine applications. The main issues to be overcome in the marine environment are: the fact that, at depth, the ambient hydrostatic pressure is much higher than the dynamic pressure, and the need for devices to be water-tight and robust. These issues have been addressed by using novel calibration coefficients and by installing the sensors and amplifier board within the probe head. A prototype device has been tested in a flume tank using LDV measurements for comparison. The probe can now be developed for trials in the marine environment.

OBJECTIVE To examine the compliance of colorectal cancer surveillance decisions for individuals at greater risk with current evidence-based guidelines and to determine whether compliance differs between surveillance models. DESIGN Prospective auditing of compliance of surveillance decisions with evidence-based guidelines (NHMRC) in two decision-making models: nurse coordinator-led decision making in public academic hospitals and physician-led decision making in private non-academic hospitals. SETTING Selected South Australian hospitals participating in the Southern Co-operative Program for the Prevention of Colorectal Cancer (SCOOP). MAIN OUTCOME MEASURES Proportions of recall recommendations that matched NHMRC guideline recommendations (March-May 2015); numbers of surveillance colonoscopies undertaken more than 6 months ahead of schedule (January-December 2015); proportions of significant neoplasia findings during the 15 years of SCOOP operation (2000-2015). RESULTS For the nurse-led/public academic hospital model, the recall interval recommendation following 398 of 410 colonoscopies (97%) with findings covered by NHMRC guidelines corresponded to the guideline recommendations; for the physician-led/private non-academic hospital model, this applied to 257 of 310 colonoscopies (83%) (P < 0.001). During 2015, 27% of colonoscopies in public academic hospitals (mean, 27 months; SD, 13 months) and 20% of those in private non-academic hospitals (mean, 23 months; SD, 12 months) were performed more than 6 months earlier than scheduled, in most cases because of patient-related factors (symptoms, faecal occult blood test results). The ratio of the numbers of high risk adenomas to cancers increased from 6.6:1 during 2001-2005 to 16:1 during 2011-2015. CONCLUSION The nurse-led/public academic hospital model for decisions about colorectal cancer surveillance intervals achieves a high degree of compliance with guideline recommendations, which should relieve burdening of colonoscopy resources.

In this paper, experiments and numerical modeling are used to quantify the effects of clearance and eccentricity on compressor performance and to examine the influence of each on flow distribution and stall margin. A change in the size of the tip-clearance gap influences the pressure rise and the stall margin of a compressor. Eccentricity of the tipclearance gap then further exacerbates the negative effects of increasing tip-clearance. There are few studies in the literature dealing with the combined effect of clearance and eccentricity. There is also little guidance for engine designers, who have traditionally used rules of thumb to quantify these effects. One such rule states that the stall margin of an eccentric machine will be equal to that of a concentric machine with uniform clearance equal to the maximum eccentric clearance. In this paper, this rule of thumb is checked using experimental data and found to be overly pessimistic. In addition, eccentric clearance causes a variation in axial velocity around the circumference of the compressor. The current study uses a three-dimensional model which demonstrates the importance of radial flow gradients in capturing this redistribution. Flow redistribution has been treated analytically in the past, and for this reason, previous modeling has been restricted to two dimensions. The circumferential variation in axial velocity is also examined in terms of the local stability of the flow by considering the stalling flow coefficient of an equivalent axisymmetric compressor with the same local tip-clearance. The large clearance sector of the annulus is found to operate beyond its equivalent axisymmetric stall limit, which means that the small clearance sector of the annulus must be stabilizing the large clearance sector. An improved rule of thumb dealing with the effects of eccentricity is presented.

Equilibrium in combination with gas chromatography/mass spectrometry (GC/MS) was used to identify volatile compounds from the leaves of 76 individual plants of Agastache rugosa representing 16 regions in South Korea. Chemometric investigation of the intraspecific variability in volatiles led to identify five main chemotypes; estragole (Type 1) as the major component, and the other four chemotypes; methyleugenol (Type2), methyleugenol+limonene (Type 3), menthone (Type 4) and menthone+pulegone (Type 5). The Soraksan region collection was classified as methyeugenol type; Hambaeksan region collection, as methyleugenol +limonene type; Bongpyeong and Inje regions (two of three sample) collection as menthone type; Hongcheon and Inje regions (one of three sample) collection as menthone+pulegone type; and all of the others collections as estragole type. INTRODUCTION The species Agastache rugosa Kuntze (Syn. Lophanthu rugosus) is a perennial herb and belongs to the Labiatae. The plant is widely distributed in Korea, China, India, Japan, and other East Asian countries and used in the Chinese folk medicine. Antitumor and cytotoxic activities of the plant were reported (Weverstahl et al., 1992) and the whole plant has been used as an agent for the treatment of cholera, vomiting, and miasma. Leaves can be used as a spice. The species is traditionally used as a medicinal plant in Korea (Jung and Shin, 1990). Previous studies showed that estragole was as a major component (56-94%) of the leaves in natural populations of A. rugosa grown in Iowa (Charles et al., 1991; Wilson et al., 1992) and in Ishikawa, Hyogo Prefecture, Japan (Fujita and Fujita, 1965). However, a population of A. rugosa (A. rugosa O. Kuntze var. methyleugenolifera) collected in Kitami, Hokkaido, contained 84-92% of methyl eugenol and only 2-6% of estragole (Fujita and Fujita, 1973). Svoboda et al. (1995) and Wilson et al. (1992) analyzed the essential oil composition using the individual samples collected in Scotland and USA, respectively, and indicated the presence of chemotypes. However, the compositional character of the chemotypes was not detailed. Essential oil content of A. rugosa from Korea was reported that the leaves contained 0.29%, the inflorescence 0.38% of essential oil. Estragole comprised approximately 80% of the essential oil (Ahn and Yang, 1991; Lee et al., 1994). In our study, we compared the characteristics of volatile components of different A. rugosa strains collected from 16 individual regions of Korea. MATERIALS AND METHODS Plant Materials Eight accession (Damyang, Garyeongsan, Gurye, Gwangyang, Jindo, Jinju, Mokpo, Suncheon) of A. rugosa collected from the southern parts of Korea were obtained from Gene Bank, RDA in Korea. These accessions were field grown at the College Experimental Farm, Seoul National University, Suwon and harvested at flowering stage. Proc. WOCMAP III, Vol. 1: Bioprospecting & Ethnopharmacology Eds. J. Bernath, E. Nemeth, L.E. Craker and Z.E.Gardner Acta Hort 675, ISHS 2005 60 Samples from other eight accessions (Bongpyeong, Geumyongsa, Hambaeksan, Hongcheon, Inje, Soraksan, Seonamsa, Tongdosa) were harvested at reproductive stage directly from the eight regions. Headspace Sample Collection From the individual plant samples, two to three grams of leaves were weighed and placed into the bottles without damaging the tissue. The leaves were immediately freezedried and sealed with teflon-coated septa and aluminum seals. GC-MS Analysis Volatile analysis was performed on equilibrium headspace autosampler (Tekmar 7000) connected with gas chromatography/mass spectrometry (Hewlett-Packard 6890/5973) equipped with “Chemstation” software. A fused-silica HP-5 capillary column (1.0 film thickness, 0.25 mm (id)×30 m, Hewlett-Packard, USA) was used through this study. Helium carrier gas was applied and the injector and detector temperatures were set at 250 and 280°C, respectively. The oven temperature was held isothermal at 80°C for 3 min and then programmed to increase at 5°C/min to 230°C. Identification of the headspace volatile compound of individual plants within each A. rugosa population was performed by comparison retention time and mass spectrum with standard compounds [αpinene, 1-octen-3-ol, myrcene, menthone, isomenthone, estragole, pulegone, βcaryophyllene, germacrene, methyleugenol] and Wiley 273 library (Wiley, USA). Statistical Analysis Principal component analysis (PCA) was done to examine the relationships between the plants from different geographical areas and volatile components. RESULTS The volatile compounds extracted from A. rugosa leaf samples mainly consisted of estragole, methyleugenol, menthone (including isomenthone), pulegone and limonene (Table 1). The volatile compounds showed large differences between regions, with significant F-values. The major volatile compounds of 11 populations (Damyang, Garyeongsan, Geumyongsa, Gurye, Gwangyang, Jindo, Jinju, Mokpo, Suncheon, Seonamsa, and Tongdosa) had significantly higher percentage of estragole than the population from other regions. Menthone (including isomenthone) was a major volatile component in Bongpyeong and Inje collections while menthone+pulegone in Hongcheon, methyleugenol+limonene in Hambaeksan, and methyleugenol in Soraksan. It has been noted that the volatile components of A. rugosa exhibited significant chemical diversity at the species level. Therefore, phenylprophanoids, monoterpenoids, and sesquiterpenoids which varied among the regions (P

To the Editor, Autoimmune diseases encompass a wide spectrum of disorders from organ specific to multisystemic involvement. Sometimes, autoimmune diseases coexist with each other and the overlap syndrome is defined by the development of clinical features of two or more autoimmune diseases simultaneously. There are a number of mechanisms implicated in the pathogenesis of these overlaps. Genetic factors, such as shared susceptible alleles, cross-reactivity of autoantibody, autoreactive T cell and cytokine imbalance have been suggested [1]. Hashimoto's thyroiditis is an organ specific autoimmune disorder. Its association with systemic autoimmune diseases has been described, including systemic lupus erythematosus, Sjogren syndrome, systemic sclerosis, and rheumatoid arthritis [2]. However, the occurrence of Hashimoto's thyroiditis and polymyositis is very rare and not well documented. We describe a 20-year-old woman with polymyositis who was diagnosed as Hashimoto's thyroiditis concomitantly. A 20-year-old woman was admitted to the hospital complaining of fever and pain with weakness in arms and thighs. Three months ago, she felt pain in the both extremities and had difficulty in standing, walking on stairs and rising arms over the head. At admission, blood pressure was 100/60 mmHg, heart rate was 110 beats per minute, and temperature was 39℃. Thyroid gland was diffusely enlarged with a smooth surface and soft consistency. Musculoskeletal examination revealed tenderness in all four extremities. Muscle strength of the extremities was 3 to 4/5 in arms and 3/5 in legs. On neurological examination, sensation, and deep tendon reflexes were normal or intact. Laboratory findings were as follows: white blood cell 23,180/mm3, hemoglobin 9.1 g/dL, platelet 511,000/mm3, erythrocyte sedimentation rate 58 mm/hr, C-reactive protein 10.4 mg/dL, serum total protein 8.5 g/dL, albumin 4.4 g/dL, aspartate transaminase (AST) 55 IU/L, creatinine 0.82 mg/dL, lactate dehydrogenase 1,296 IU/L (normal range, 218 to 472), creatine phosphokinase (CPK) 386 IU/L (normal range, 30 to 334), and aldolase 7.6 U/mL (normal range, 2 to 8). Thyroid stimulating hormone was 2.39 µU/mL (normal range, 0.35 to 5.50), free T4 1.03 ng/dL (normal range, 0.89 to 1.80), antithyroglobulin 732 IU/mL (normal range, 0 to 40), antimicrosomal antibody 245 IU/mL (normal range, 0 to 25), and thyroid stimulating immunoglobulin was 5% (normal range, 0 to 15). Immunological examination revealed the following: antinuclear antibody positive at 1 : 40 in speckled pattern, rheumatoid factor, anti-SSA, anti-SSB, anti-dsDNA antibody, anti-Scl-70 antibody, antiribonuclear protein and anti-Jo-1 antibody were all negative. Ultrasonogram of the thyroid gland demonstrated diffuse enlargement of the thyroid gland and 1 cm sized hypovascular echogenic nodule on right upper pole. An electromyography (EMG) finding was occasional small fasciculations and polyphasic motor unit potentials of low amplitude and short duration, suggestive of myopathy. Histological examination of the resected thyroid right lobe revealed follicular cell proliferative lesions in background of parenchymal extensive mononuclear inflammatory cell infiltration and oxyphilic changes of follicular epithelium, consistent with nodular hyperplasia in Hashimoto's thyroiditis (Fig. 1). Muscle biopsy specimen from the quadriceps showed necrotic and regenerating various sized muscle fiber and phagocytosis with endomyseal inflammatory cell infiltration and the perivascular infiltration of mononuclear cells, consistent with polymyositis (Fig. 2). She was diagnosed as having polymyositis and Hashimoto's thyroiditis and was treated with prednisolone (50 mg/day) and methotrexate (10 mg/wk). Her symptoms remarkably improved after treatment. Fever and myalgia disappeared quickly and muscle strength improved gradually. Figure 1 Microscopic finding of thyroid gland showing extensive mononuclear inflammatory cell infiltration of the parenchyma and oxyphilic changes of follicular epithelium with follicular cell proliferative lesions (H&E, × 100). Figure 2 Muscle biopsy specimen reveals interstitial mononuclear cell infiltration. Both regenerating and degenerating muscle fibers are scattered (H&E, × 200). This case showed some difficulties of interpreting laboratory data. Although, the levels of certain muscle enzyme (AST and CPK) were not so high at initial evaluation. The diagnosis of polymyositis was made by clinical, histological, and EMG findings. The conceivable explanation of these laboratory ambiguities lies in the use of corticosteroid for several weeks before the test. Although the pathogenesis and the nature of the relationship between thyroid autoimmunity and autoimmune diseases is not completely established, some hypotheses may be implicated: 1) immune modulatory effects of antithyroid antibodies; 2) molecular mimicry between thyroid and disease specific epitopes; and 3) genetic link between antithyroid autoimmunity and the susceptibility to autoimmune disease [2]. Cross-reactivity of antithyroid antibodies or autoreactive T cells with other organs and cytokine imbalance may also implicated [2,3]. About 2% of inflammatory myopathy patients exerted thyroid autoimmunity. Suppressor T cell dysfunction and lymphocyte mediated cytotoxicity have been described in patient with polymyositis and there are some evidences of suppressor T cell dysfunction in autoimmune thyroiditis [2,4]. It could be hypothesized that coexisting autoimmune thyroiditis and inflammatory myopathy develop from the common autoimmune pathogenic mechanism. In conclusion, systemic and thyroid autoimmune diseases may overlap with each other. It is important to be aware that polymyositis and autoimmune thyroiditis can coexist and a thorough evaluation of both conditions may be necessary in patients presenting with myalgia or muscle weakness.

Rehmannia glutinosa is one of the most important medicinal crops in Korea. However, various plant pathogens, including Fusatium spp., cause great damage on R. glutinosa and result in enormous economic losses. This study was conducted to breed Fusarium-resistant plants by using Agrobacterium tumefaciences and AFP (anti-fungal protein) gene. The plant material used was a native accession of R. glutinosa. The PCR analysis was conducted to verify transgenicity. Based on the PCR analysis, nptII band was observed in transgenic plant genome. Southern blot and AFP protein analyses also showed the expression of this gene in transgenic plants. Expression of AFP in transgenic plants offers the possibility of developing resistance to fungal infection.

An efficient transformation protocol was established for Chinese foxglove, Rehmannia glutinosa L., using Agrobacterium tumefaciens. Putative transgenic plants were induced from leaf explants co-cultivated with Agrobacterium. Detection of the neomycin phosphotransferase gene, high activity of β-glucuronidase (GUS) transcripts and histochemical localization of GUS confirmed the integrative transformation of Chinese foxglove. This result demonstrates the potential for using A. tumefaciens to transfer important genes into commercial Chinese foxglove cultivars.

The transformed root culture of Polygonum tinctorium Lour. was established by infecting leaf explants with Agrobacterium rhizogenes A4. These cultures were examined for their growth and indigo content under various culture conditions. Among the four different culture media tested, SH medium showed the highest yield for root growth (28 mg dry wt/30 ml) and indigo production (152 μg/dry wt). In SH medium, 30 g sucrose l−1, 2500 mg KNO3 l−1, 300 mg NH4H2PO4 l−1 were the best conditions for indigo production at pH 5.7. The production of indigo in hairy roots slightly increased with the addition of 200 mg chitosan l−1 (186 μg/dry wt) and 20 U pectinase l−1 (181 μg/dry wt).

In this paper, the evolution of dimethylsulfoxide (DMSO) concentration and moisture content (MC) of garlic shoot tips was studied during the course of a vitrification protocol using the PVS2 vitrification solution. DMSO concentration of shoot tips increased rapidly, reaching 34.1 mg per g fresh weight after 20 min of PVS2 treatment and remained stable afterwards, while moisture content decreased from 82 to 60 percent, reaching 53 percent after 60 min. A reverse process was observed during unloading. There was a highly significant negative correlation between shoot tip moisture content and DMSO concentration during the dehydration and unloading treatments. Using unloading solutions with osmolarities between 0.42 and 2.29 Osm led to very different shoot tip MCs, between 63.55 and 81.24 percent, while DMSO concentration was between 14.83 and 19.97 mg per g fresh weight. After 24 h on recovery medium, DMSO concentration of shoot tips had decreased to 3.2 mg per g fresh weight.

This paper investigates the effect of the origin and size of the explants employed and of the preconditioning (cold acclimation, preculture) and loading treatments on survival and regeneration of cryopreserved garlic shoot apices using vitrification with the PVS3 vitrification solution. Both the origin and size of explants had a significant effect on regeneration of cryopreserved apices. Higher regeneration was generally observed with apices excised from bulbs and bulbils, followed by cloves, and those originated from larger propagules regrew more rapidly. Smaller apices (1.5 or 3.0 mm in diameter) displayed higher regeneration than large ones (4.5 mm in diameter). Cold acclimation at 5 degree C of apices before freezing had no positive effect on regeneration after cryopreservation. Preculture of apices at 10 or 23 degree C for more than 3 days had a detrimental effect on regeneration. The optimal sucrose concentration in the preculture medium was 0.3-0.5 M. Loading apices for 30 or 60 min at 23 degree C in medium containing 2 M glycerol + 0.4 M sucrose or 1 M glycerol + 0.8 M sucrose had no effect on regeneration after cryopreservation, in comparison with apices cryopreserved without loading treatment. Under optimal conditions, regeneration of cryopreserved apices sampled from large cloves was above 90 percent.

This study investigated the tolerance to desiccation and freezing of tea seeds, embryonic axes (EAs) and cotyledonary embryonic axes (CEAs, consisting of EAs with portions of cotyledons still attached). No seeds germinated after desiccation and cryopreservation. EAs extracted from seeds desiccated to 18.9% moisture content (fresh weight basis) and cryopreserved showed 20.7% survival but plantlet production from these EAs was impossible. When EAs and CEAs were extracted from seeds before being submitted to desiccation and freezing, survival of control and frozen samples was equivalent with both types of materials. However, plantlet production was significantly higher from control and cryopreserved CEAs than EAs. The maturity stage of the seeds from which CEAs were extracted had an important effect on their survival and plant production percentages, mature seeds providing better results than early mature and late mature seeds. The highest percentages of plantlet production from cryopreserved CEAs, which ranged between 75.1 and 80.4%, were achieved for EA moisture contents between 21.5 and 15.0%.

We have purified a 21-kDa protein, designated as P1, from Rehmannia glutinosa to homogeneity by ammonium sulfate precipitation, anion exchange chromatography, hydrophobic interaction chromatography, and preparative native PAGE. The purified P1 had chitin degradation activity. The N-terminal amino acid sequence of P1 indicated that it is very similar to those of thaumatin and other reported thaumatin-like proteins.

A cumulative dose, multiple-trial test procedure was developed in eight pigeons trained to discriminate among saline, 1.8mg/kg morphine, and 10mg/kg morphine. Initially, single-trial tests were used to evaluate stimulus effects of acute doses of morphine. Next, the test procedure was altered so that cumulative doses were tested within a single session. Results from cumulative-dose tests of morphine were consistent with those from single-trial tests. The cumulative-dose test procedure was then used to characterize the high-dose and low-dose morphine training stimuli. The mu agonists etorphine, fentanyl, methadone and morphine dose-dependently evoked both low-dose and high-dose morphine-like effects, with a similar potency order (etorphine > fentanyl > methadone = morphine). In contrast, nalbuphine evoked only low-dose effects, consistent with low efficacy mu agonist activity. The kappa opiate U50,488H evoked saline-key responses, whereas the non-opiate ketamine evoked saline-key responses in the majority of pigeons, but high-dose and/or low-dose responding in others. Naltrexone dose-dependently antagonized both low-dose and high-dose stimulus effects of morphine, but not its rate-decreasing effects. Apparent pA(2) values for naltrexone were 7.2 for low-dose stimulus effects of morphine, and 7.4 for high-dose effects. These characteristics suggest that stimulus effects of both low and high training doses of morphine are mediated by common, presumably mu opioid, receptor populations.

Pharmacological selectivity of tolerance to the discriminative stimulus effects of morphine or d amphetamine was examined in pigeons trained to discriminate among 3.2mg/kg morphine, saline, and 1.8mg/kg d-amphetamine under a 3-key fixed-ratio 30 schedule of food delivery. Cumulative doses of morphine (0.32-10mg/kg) or d-amphetamine (0.10-3.2mg/kg) evoked morphine-or d-amphetamine-key responding, respectively, in a dose-dependent manner. Suspending training and administering repeated doses of morphine (32mg/kg b.i.d.) for 1 week increased the dose of morphine required for morphine-key responding approximately 5-fold, without altering sensitivity to d-amphetamine. Conversely, repeated treatment with d-amphetamine (5.6mg/kg b.i.d.) increased the dose of d-amphetamine required for d-amphetamine-key responding approximately 7-fold, without decreasing sensitivity to morphine. Repeated treatment with saline (1ml/kg b.i.d.) for 1 or 2 weeks did not alter sensitivity to stimulus effects of either morphine or d-amphetamine. Sensitivity to stimulus effects of morphine recovered fully within 1 week after morphine treatment ended; sensitivity to stimulus effects of d-amphetamine recovered partially within 3 days after d-amphetamine treatment ended. For morphine, but not for d-amphetamine, increases in the dose required for stimulus effects were accompanied by increases in the dose required for rate-reducing effects. These results demonstrate that tolerance to discriminative stimulus effects of morphine and d-amphetamine is pharmacologically selective and suggest that pharmacotherapies targeted to one drug of abuse may produce little change in sensitivity to subjective effects of drugs from a different pharmacological class.