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The olivo-cerebellar circuit is thought to play a crucial role in the pathophysiology of essential tremor (ET). Whether olivo-cerebellar circuit dysfunction is also present at rest, in the absence of clinical tremor and linked voluntary movement, remains unclear. Assessing this network in detail with fMRI is challenging, considering the brainstem is close to major arteries and pulsatile cerebrospinal fluid–filled spaces obscuring signals of interest. Here, we used methods tailored to the analysis of infratentorial structures. We hypothesize that the olivo-cerebellar circuit shows altered intra-network connectivity at rest and decreased functional coupling with other parts of the motor network in ET. In 17 ET patients and 19 healthy controls, we investigated using resting state fMRI intracerebellar functional and effective connectivity on a dedicated cerebellar atlas. With independent component analysis, we investigated data-driven cerebellar motor network activations during rest. Finally, whole-brain connectivity of cerebellar motor structures was investigated using identified components. In ET, olivo-cerebellar pathways show decreased functional connectivity compared with healthy controls. Effective connectivity analysis showed an increased inhibitory influence of the dentate nucleus towards the inferior olive. Cerebellar independent component analyses showed motor resting state networks are less strongly connected to the cerebral cortex compared to controls. Our results indicate the olivo-cerebellar circuit to be affected at rest. Also, the cerebellum is "disconnected" from the rest of the motor network. Aberrant activity, generated within the olivo-cerebellar circuit could, during action, spread towards other parts of the motor circuit and potentially underlie the characteristic tremor of this patient group. [ABSTRACT FROM AUTHOR]

The structure, mechanical, and tribological properties of polyimide (PI) and polyetherimide (PEI) based composites have been studied in the paper. The PEI macromolecular chain is more flexible and contains active oxygen atoms. To impart antifriction properties by forming a transfer film (TF) on the counterface/tribofilm on a sliding surface, the polymers were filled with polytetrafluoroethylene (PTFE) particles. The tribological tests were carried out by the ball-on-disk and block-on-ring schemes under dry sliding friction on metal and ceramic counterfaces. As shown, at point tribological contact, the possibility of shielding the rubbed materials by PTFE film provided the wear rate (WR) and the coefficient of friction (CoF) μ at approximately the same low level regardless of a polymer matrix and a counterface material. At a linear tribological contact, the WR of the PI/PTFE was 2–3 times lower (in contrast to PEI/PTFE) that was caused by a more uniform distribution of solid-lubricant particles in a bulk composite. The revealed structure pattern, in friction against a ceramic counterface, suppressed the formation of wear products at the running-in stage, providing the minimum wear rate WR ~ 0.2·10–6mm3 / N·m at low value μ ~ 0.1. The tribochemical interaction of the steel counterface with the polymer matrix prevented achieving the low value μ > 0.18 for PI/PTFE and this, due to impossibility to adhere a tribofilm, did not allow attaining the wear intensity less than WR < 2·10–6 mm3/N·m. In case of PI/PTFE, the wear rate was higher than 3·10–6 mm3/N·m. [ABSTRACT FROM AUTHOR]

In our quest for the presence of large complex molecules containing a majority of carbon in the interstellar medium (ISM), the search for graphene plays a central role due to its nature in making other carbon structures. Although the ingredients for graphene synthesis are present in the ISM, conclusive laboratory evidence of such formation is lacking. Therefore, in our laboratory experiments simulating the cold ISM conditions, we subjected icy mantles of benzonitrile, an aromatic with a cyanide side chain that has recently been detected in the interstellar medium, to vacuum ultraviolet photon irradiation. The irradiated ice was observed to leave a residue upon warming to room temperature. The residue was removed from the substrate and placed on a Quantifoil grid for electron microscopy analysis. Transmission electron microscopy showed quantum dots (QD) and nitrogen-doped graphene (N-Graphene) sheets. Diffraction and energy-dispersive X-ray spectroscopy revealed the crystalline nature and carbon–nitrogen composition, of the observed graphene sheet. This is the first evidence of QD and N-graphene synthesis in ice irradiation at interstellar temperatures. [ABSTRACT FROM AUTHOR]

The recent discovery of hydroxylamine (NH2OH) molecule in the interstellar medium emphasizes the need to study the molecule in laboratory astrochemical ice analogues. Here, we present the first vacuum ultraviolet photoabsorption spectrum of hydroxylamine ice synthesized in-situ in an ammonia–oxygen (6:1) ice mixture irradiated by ~ 10 eV photons from synchrotron radiation source. The appearance of a new band between the 180–240 nm, with a band centered at ~ 207 nm, is assigned to the characteristic absorption of hydroxylamine molecule in the ice phase. This band maybe used in ammonia dominated, oxygen bearing, icy surfaces for the identification of hydroxylamine. [ABSTRACT FROM AUTHOR]

Among the most commonly existing thiol molecules, methanethiol and ethanethiol were discovered in the interstellar medium and identification of the next larger thiol molecule, propanethiol, is long awaited. By simulating icy astrochemical conditions and probing propanethiol ices under infrared spectroscopy we propose the use of SH stretching vibrations observed in the propanethiol molecular ice as a probe towards its identification in the interstellar medium. Though there are conformational changes within the ice (as observed in both VUV and IR spectra), the SH stretching vibration of propanethiol is observed to be unique among the set of thiol molecules, methanethiol and ethanethiol, which enables the detection of propanethiol ice in interstellar dust mantles using the James Webb Space Telescope. [ABSTRACT FROM AUTHOR]

Summary: There is no clear consensus on definition, cut-points or standardised assessments of sarcopenia. We found a lower limb strength assessment was at least as effective in predicting balance, mobility and falls in 419 older people as muscle mass-based measures of sarcopenia. Introduction: There is currently no consensus on the definition, cut-points or standardised assessments of sarcopenia. This study aimed to investigate whether several published definitions of sarcopenia differentiate between older people with respect to important functional and health outcomes. Methods: Four hundred nineteen community-living older adults (mean age 81.2 ± 4.5, 49 % female) completed assessments of body composition (dual-energy X-ray absorptiometry), strength, balance, mobility and disability. Falls were recorded prospectively for a year using monthly calendars. Sarcopenia was defined according to four skeletal mass-based definitions, two strength-based definitions (handgrip or knee extensor force) and a consensus algorithm (low mass and low strength or slow gait speed). Obesity was defined according to percentage fat mass or waist circumference. Results: The four skeletal mass-based definitions varied considerably with respect to the percentage of participants classified as sarcopenic and their predictive accuracy for functional and health outcomes. The knee extension strength-based definition was equivalent to or better than the mass-based and consensus algorithm definitions; i.e. weaker participants performed poorly in tests of leaning balance, stepping reaction time, gait speed and mobility. They also had higher physiological fall risk scores and were 43 % more likely to fall at home than their stronger counterparts. Adding obesity to sarcopenia definitions identified participants with greater self-reported disability. Conclusions: A simple lower limb strength assessment was at least as effective in predicting balance, functional mobility and falls in older people as more expensive and time-consuming muscle mass-based measures. These findings imply that functional terms such as muscle weakness or motor impairment are preferable to sarcopenia. [ABSTRACT FROM AUTHOR]

Summary: Caucasian reference data are used to classify bone mineral density in US women of all races. However, use of Chinese American reference data yields lower osteoporosis prevalence in Chinese women. The reduction in osteoporosis labeling may be relevant for younger Chinese women at low fracture risk. Introduction: Caucasian reference data are used for osteoporosis classification in US postmenopausal women regardless of race, including Asians who tend to have lower bone mineral density (BMD) than women of white race. This study examines BMD classification by ethnic T-scores for Chinese women. Methods: Using BMD data in a Northern California healthcare population, Chinese women aged 50-79 years were compared to age-matched white women (1:5 ratio), with femoral neck (FN), total hip (TH), and lumbar spine (LS) T-scores calculated using Caucasian versus Chinese American reference data. Results: Comparing 4039 Chinese and 20,195 white women (44.8 % age 50-59 years, 37.5 % age 60-69 years, 17.7 % age 70-79 years), Chinese women had lower BMD T-scores at the FN, TH, and LS (median T-score 0.29-0.72 units lower across age groups, p < 0.001) using Caucasian reference data. Using Chinese American BMD reference data resulted in an average +0.47, +0.36, and +0.48 units higher FN, TH, and LS T-scores, respectively, reducing the prevalence of osteoporosis (T-score ≤ −2.5) in Chinese women at the FN (16.7 to 6.6 %), TH (9.8 to 3.2 %), and LS (23.2 to 8.9 %); osteoporosis prevalence at any one of three sites fell from 29.6 to 12.6 % (22.4 to 8.1 % for age 50-64 years and 43.2 to 21.0 % for age 65-79 years). Conclusion: Use of Chinese American BMD reference data yields higher (ethnic) T-scores by 0.4-0.5 units, with a large proportion of Chinese women reclassified from osteoporosis to osteopenia. The reduction in osteoporosis labeling with ethnic T-scores may be relevant for younger Chinese women at low fracture risk. [ABSTRACT FROM AUTHOR]

Ceramics are a promising insulating material for high temperature environment. To qualify for in-core use in nuclear reactors, there are many other materials requirements to be met, such as neutron irradiation resistance, corrosion resistance, low thermal conductivity, high coefficient of thermal expansion, high strength, high fracture toughness, ease of fabricability, etc. And among the promising ceramics meeting most of the requirements, with the exception of fabricability, is yttria-stabilized zirconia (YSZ). Like all ceramics, YSZ is hard, brittle and difficult to machine. At CanmetMATERIALS, YSZ-based composites for in-core insulation that are machine-able and capable of being formed into complex shapes have been developed. In this paper, the focus is geared towards the fabrication and property evaluation of such composites. In addition, the machinability aspect of the YSZ composites was addressed with a demonstration of a machined component. [ABSTRACT FROM AUTHOR]

Objectives: Evaluate a 4-week dementia specific nutrition education intervention to determine long term knowledge and healthy dietary behaviour changes in 72 elderly men and women. Design: A mixed method design used qualitative findings to triangulate quantitative within-subject changes to determine efficacy and sustained dietary behaviour change. Setting: Community. Participants: 72 independently-living individuals. Intervention: 4-week dementia specific nutrition education intervention. Measurements: Change in participant attitude, confidence, dietary patterns, cooking behaviour, and knowledge were analysed within-subjects using non-parametric repeated-measures procedures. Significance level was set at 5% (α = 0.05). Effect size (ES) was reported and identified as small (S), medium (M) or large (L) if a significant change was observed. Results: Compared to before the nutrition education intervention participants had an increase in total knowledge (p < 0.001, ES = 0.972 (L)), consumed a greater variety of vegetables (p = 0.007, ES = 0.35 (M)), used less salt (p = 0.006, ES =-0.42 (M-L)) and increased spice use (p < 0.001, ES = 0.40 (M-L)). Participants overcame barriers to enable sustained change, held a positive view on healthy living and believed government should invest in this sector of the community. Sharing and socialisation emerged as important themes that increased program satisfaction. Conclusion: The dementia specific nutrition program produced a large effect in knowledge improvement from pre to post, which was retained at follow up, consolidated observational and participatory learning which produced a moderate increase in healthy dietary behaviours which participants valued and sustained. [ABSTRACT FROM AUTHOR]

Summary: Contemporary femur fracture rates were examined in northern California women and compared by race/ethnicity. During 2006-2012, hip fracture rates declined, but diaphyseal fracture rates increased, especially in Asians. Women with diaphyseal fracture were younger and more likely to be bisphosphonate-treated. These disparities in femur fracture should be further examined. Introduction: The epidemiology of diaphyseal femur fracture differs from proximal femur (hip) fracture, although few studies have examined demographic variations in the current era. This study examines contemporary differences in low-energy femur fracture by race/ethnicity in a large, diverse integrated health-care delivery system. Methods: The incidence of hip and diaphyseal fracture in northern California women aged ≥50 years old during 2006-2012 was examined. Hip (femoral neck and pertrochanteric) fractures were classified by hospital diagnosis codes, while diaphyseal (subtrochanteric and femoral shaft) fractures were further adjudicated based on radiologic findings. Demographic and clinical data were obtained from health plan databases. Fracture incidence was examined over time and by race/ethnicity. Results: There were 10,648 (97.3 %) hip and 300 (2.7 %) diaphyseal fractures among 10,493 women. The age-adjusted incidence of hip fracture fell from 281 to 240 per 100,000 women and was highest for white women. However, diaphyseal fracture rates increased over time, with a significant upward trend in Asians (9 to 27 per 100,000) who also had the highest rate of diaphyseal fracture. Women with diaphyseal fracture were younger than women with hip fracture, more likely to be of Asian race and to have received bisphosphonate drugs. Women with longer bisphosphonate treatment duration were also more likely to have a diaphyseal fracture, especially younger Asian women. Conclusion: During 2006 to 2012, hip fracture rates declined, but diaphyseal fracture rates increased, particularly among Asian women. The association of diaphyseal fracture and bisphosphonate therapy should be further investigated with examination of fracture pattern. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Loss of CD44 attenuates aberrant GM-CSF signaling in Kras G12D hematopoietic progenitor/precursor cells and prolongs the survival of diseased animals" published in a previous issue.

Objective:To examine the risk and etiology of preterm delivery in women with polycystic ovary syndrome (PCOS).Study Design:Retrospective cohort study comparing preterm delivery rate among non-diabetic PCOS and non-PCOS women with singleton pregnancy. Multivariable logistic regression was used to identify predictors of preterm delivery among PCOS women.Result:Among 908 PCOS women with singleton pregnancy, 12.9% delivered preterm compared with 7.4% among non-PCOS women (P<0.01). Causes of preterm delivery among PCOS women included preterm labor (41%), cervical insufficiency (11%), hypertensive complications (20%), preterm premature rupture of membranes (15%), fetal-placental concerns (9%) and intrauterine fetal demise (5%). Maternal age, race/ethnicity and nulliparity were significant predictors of preterm delivery in PCOS, whereas body mass index and fertility medications were not.Conclusion:A higher proportion of PCOS women delivered preterm (12.9%) compared with non-PCOS women, with the majority of cases due to spontaneous preterm birth. Future studies should explore etiologies and strategies to improve pregnancy outcomes in PCOS. [ABSTRACT FROM AUTHOR]

Summary: Hospital diagnosis codes are useful for assessing hip fracture rates in large populations. However, these codes do not reliably differentiate hip fractures that occur in the subtrochanteric region. Identification of subtrochanteric fractures requires review of radiographic images to distinguish these fractures from the more commonly occurring trochanteric fractures. Purpose: This study examines the accuracy of coded hospital diagnoses for hip fracture compared to fracture site verification based on operative and radiologic data. The variability in subtrochanteric fracture assignment was also examined using different anatomic criteria. Methods: This retrospective study includes female members of Kaiser Permanente Northern California age 60 years and older with nontraumatic hip fracture during 2007-2008. Anatomic site was verified by operative and radiologic records, including radiographic image review for fractures occurring in the subtrochanteric region. Two different criteria were compared for subtrochanteric fracture. Results: We identified 2,824 women with incident hip fracture during the 2-year period. The average age was 82.9 ± 8.2 years and 15% were non-White. International Classification of Diseases, Ninth Revision (ICD-9) coding was accurate for femoral neck and trochanteric fractures (>90% confirmed by operative/radiologic reports), compared to only 26% for subtrochanteric fractures using the Orthopedic Trauma Association (OTA) criteria for subtrochanteric fracture. Using OTA classification, 1.3% of hip fractures were assigned as subtrochanteric compared to 4.2% when the criteria were broadened to include the lesser trochanter. Both femoral neck and pertrochanteric fracture rates increased exponentially with age, while age-related rates in subtrochanteric fracture differed by diagnostic classification method; the broader criteria including the lesser trochanter produced age-related trends that mirrored femoral neck and pertrochanteric fractures. Conclusion: Unlike femoral neck and pertrochanteric fractures, epidemiologic studies of subtrochanteric fractures cannot rely on ICD-9 codes alone. Review of radiologic images using OTA criteria is required for identification of subtrochanteric fractures occurring below the lesser trochanter. [ABSTRACT FROM AUTHOR]

Background: Intraoperative microelectrode recording (MER) for targeting during deep brain stimulation (DBS) procedures has been evaluated over a period of 4 years, in 57 consecutive patients with Parkinson's disease, who received DBS in the subthalamic nucleus (STN-DBS), and 28 consecutive patients with either dystonia (23) or Parkinson's disease (five), in whom the internal segment of the globus pallidus (GPi-DBS) was targeted. Methods: The procedure for DBS was a one-stage bilateral stereotactic approach using a combined electrode for both MER and macrostimulation. Up to five micro/macro-electrodes were used in an array with a central, lateral, medial, anterior, and posterior position. Final target location was based on intraoperative test stimulation. Findings: For the STN, the central trajectory was chosen for implantation in 50% of the cases and for the globus pallidus internus (GPi) in 57% of the cases. Furthermore, in 64% of the cases, the channel selected for the permanent electrode corresponded with the trajectory having the longest segment of STN MER activity. For the GPi, this was the case in 61%. The mean and standard deviation of the deepest contact point with respect to the magnetic resonance imaging (MRI)-based target for the STN was 2.1 ± 1.5 mm and for the GPi was −0.5 ± 1.2 mm. Conclusions: MER facilitates the selection of the final electrode location in STN-DBS and GPi-DBS, and based on the observed MER activity, a pre-selection could be made as to which channel would be the best candidate for macro-test stimulation and at which depth should be stimulated. The choice of the final location is based on intraoperative test stimulation, and it is demonstrated that regularly it is not the central channel that is chosen for implantation. On average, the target as defined by MER activity intensity was in accordance with the MRI-based targets both for the STN and GPi. However, the position of the best MER activity did not necessarily correlate with the locus that produced the most beneficial clinical response on macroelectrode testing intraoperatively. [ABSTRACT FROM AUTHOR]

Introduction: Although clinical trials indicate that oral bisphosphonates reduce osteoporotic fracture risk, compliance with bisphosphonate therapy in practice is suboptimal, with 1-year discontinuation rates exceeding 50%. Methods: We conducted a retrospective cohort study among female members of a large integrated health care delivery system (Kaiser Permanente of Northern California), age 45 years and older, to determine their persistence with weekly alendronate (defined as continuous use, allowing for a refill gap of 60 days), predictors of discontinuation, and subsequent osteoporosis therapy. We also examined the effect of varying the refill gap from 30 to 120 days on the discontinuation rate. From 2002 through 2003, we identified 13,455 women (age 68.8 ± 10.4 years) who initiated weekly oral alendronate therapy. Results: Using a 60-day refill gap, the 1-year discontinuation rate was 49.6% [95% confidence interval (CI) 48.8-50.4%]; this increased to 58.0% (CI 57.2-58.8%) with a 30-day gap and decreased to 42.2% (CI 41.1-43.0%) with a 120-day gap. Among those who discontinued therapy, about one-third restarted alendronate or another osteoporosis drug within 6 months. Baseline factors associated with alendronate discontinuation included prior bone mineral density testing [adjusted odds ratio (OR) 0.64, CI 0.60-0.69], prior postmenopausal hormone therapy (OR 0.78, CI 0.73-0.84), prior high-dose oral glucocorticoid therapy (OR 1.26, CI 1.05-1.51), prior gastrointestinal diagnoses (OR 1.21, CI 1.09-1.36), and high number of therapeutic classes of prescriptions filled in the prior year (OR 1.21, CI 1.10-1.32), although the final model had limited explanatory power. Conclusions: We conclude that apparent discontinuation rates are high within 1 year after treatment initiation, although a subset of women appears to restart bisphosphonate or other osteoporosis therapy. Because intermittent use and/or poor adherence is common, discontinuation rates based on data from administrative databases are sensitive to the refill gap length. In addition, we identified no clinical factors highly predictive of discontinuation. [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) asymptotic theory for dynamic analysis of doubly curved laminated piezoelectric shells is formulated on the basis of 3D piezoelectricity. By using the direct elimination, we reduce the twenty-two basic equations of 3D piezoelectricity to eight differential equations in terms of eight primary variables of elastic and electric fields. In the formulation, multiple time scales are introduced to eliminate the secular terms so that the asymptotic expansion is uniform and feasible. By means of nondimensionalization, asymptotic expansion and successive integration, we finally can obtain recurrent sets of governing equations for various order problems. The classical laminated piezoelectric shell theory (CST) is derived as a first-order approximation to the 3D piezoelectricity. Higher-order corrections can be determined by considering the solvability and orthonormality conditions in a systematic and consistent way. Several benchmark solutions for various piezoelectric laminates are given to demonstrate the performance of the theory. [ABSTRACT FROM AUTHOR]

Exercise and relaxation decrease blood pressure. Qigong is a traditional Chinese exercise consisting of breathing and gentle movements. We conducted a randomised controlled trial to study the effect of Guolin qigong on blood pressure. In all, 88 patients with mild essential hypertension were recruited from the community and randomised to Goulin qigong or conventional exercise for 16 weeks. The main outcome measurements were blood pressure, health status (SF-36 scores), Beck Anxiety and Depression Inventory scores. In the qigong group, blood pressure decreased significantly from 146.3±7.8/93.0±4.1 mmHg at baseline to 135.5±10.0/87.1±7.7 mmHg at week 16. In the exercise group, blood pressure also decreased significantly from 140.9±10.9/93.1±3.5 mmHg to 129.7±11.1/86.0±7.0 mmHg. Heart rate, weight, BMI, waist circumference, total cholesterol, renin and 24 h urinary albumin excretion significantly decreased in both groups after 16 weeks. General health, bodily pain, social functioning and depression also improved in both groups. No significant differences between qigong and conventional exercise were found. In conclusion, Guolin qigong and conventional exercise have similar effects on blood pressure in patients with mild hypertension. While no additional benefits were identified, it is nevertheless an alternative to conventional exercise in the nondrug treatment of hypertension.Journal of Human Hypertension (2005) 19, 697–704. doi:10.1038/sj.jhh.1001884; published online 19 May 2005 [ABSTRACT FROM AUTHOR]

A protocol combining purge-and-trap (P&T) and solid-phase microextraction (SPME) was established for the analysis of volatile organic compounds (VOCs) in the wastewater plant of high-tech industries. Over 60 VOCs could be analyzed by P&T coupled to gas chromatography/mass spectrometry (P&T-GC-MS). Four polar VOCs commonly used in the high-tech industries were determined by SPME coupled to gas chromatography/flame ionization detection (SPME-GC-FID). The limits of detection for the analytes were less than 1.1 μg L−1 with P&T-GC-MS, and between 1.5 and 12.5 μg L−1 with SPME-GC-FID. Satisfactory recoveries (83% to 130%) were obtained. Real samples were analyzed from a wastewater treatment plant during various stages of treatment. The major pollutant in the wastewater influent was found to be acetone (>4 ppm). [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the exposure of synthetic leather workers to dimethylformamide (DMF), epichlorohydrin (ECH) and toluene, in a manufacturing plant. The correlation between biological and environmental monitoring for DMF was also investigated. Environmental monitoring of the three solvents included personal and area sampling based on time of day (morning and afternoon). Urine samples were taken at the end of the shift and urinary N-methylformamide (NMF) was then used to biologically monitor DMF levels. Results for solvent concentrations based on air sampling were considerably higher in area than in personal sampling. Of 41 area samples, 15 (36.6%) and five (12.2%) exceeded permissible exposure levels for DMF and ECH, respectively, compared with 22 (28.6%) and three (3.9%) based on 77 personal samples. Overall, urinary NMF concentrations were lower than the Biological Exposure Index (BEI) suggested by the American Conference of Governmental Industrial Hygienists (ACGIH). A significant correlation (r=0.32; P < 0.05) was found between environmental and biological monitoring. Even though urinary NMF concentration was within permissible levels for Taiwan, the authors recommend that immediate measures be taken to decrease DMF and ECH concentrations in synthetic leather manufacturing plants. [ABSTRACT FROM AUTHOR]

Short, thick-film capillary columns can solve most of the routine applications of gas chromatography in much shorter time than packed columns. A theoretical and experimental study shows the contribution of various factors involved and permits optimization of conditions for the separation of sulfur compounds with good resolution and shortened analysis time, using gas chromatography coupled with a sulfur chemiluminescence detector. [ABSTRACT FROM AUTHOR]

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Arsenic-resistant Chinese hamster ovary (CHO) cells were established by progressively increasing the concentration of sodium arsenite in culture medium. One of the resistant clones, SA7, was also cross-resistant to As(V), Zn, Fe(II), Co, and Hg. The susceptibilities to sodium arsenite in parental CHO cells, revertant SA7N cells, and resistant SA7 cells were correlated with their intracellular glutathione (GSH) levels and glutathione S-transferase (GST) activity. The resistance in SA7 cells was diminished by depletion of GSH in cells after treatment with buthionine sulfoximine. Furthermore, after reexposure of revertant SA7N cells to sodium arsenite, the intracellular GSH levels, GST activity, and resistance to sodium arsenite were raised to the same levels as SA7 cells. These data indicate that the elevation of intracellular GSH levels and GST activity in SA7 cells may be responsible for the resistance to arsenite. A p25 protein, which could be a monomer subunit of GST, accumulated in SA7 cells. In addition, an outward transport inhibitor, verapamil, indiscriminately increased the arsenite toxicity in resistant and parental cells. [ABSTRACT FROM AUTHOR]

By participating in an International Hydrocarbons Intercomparison Experiment, a method for the determination of nonmethane hydrocarbons was evaluated. The method involves Tenax-TA sampling, thermal desorption and preconcentration combined with capillary gas chromatography with flame ionization detection. Sixty target compounds from C2 to C11 were separated by using a megabore capillary column with a thick film of bonded nonpolar siloxane stationary phase (5 μm, Rtx-1). The unusually thick film in the column was an advantage for resolving light hydrocarbons (C2−C3) at room temperature. The percent difference between the National Institute of Standards and Technology (NIST) and our laboratory in the intercomparison experiment is in the range of 0.99%–19.70%. [ABSTRACT FROM AUTHOR]

Attempts have been made to employ magnesium oxide as the preconcentration agent for determination of trace metal sin seawater by neutron activation analysis. Hydrous magnesium oxide can efficienthy adsorb most cationic transition metals and rare earths in a simple water system. The adsorption behavior is believed to depend mainly from the association of the cationic species of the metals with MgO adsorbent. In seawater matrix some of the metal ions such as Hg2+, Ni2+, etc. may become inefficiently adsorbed owing to the formation of highly stable metal-chloro complexes with chloride ion. Usually the adsorption efficiencies of the metals can be recovered to be as high as the case in the simple water system if an acidified seawater (to pH≤1) is subjected to the adsorption experiment. In practice, a large volume of seawater (5 1) is stirred with a small amount of hydrous MgO (1 g). Thereafter, the trace metals adsorbed MgO is separated and taken to be neutron activated. The abundant sodium ion and ubiquitous bromide ion can be obviated by the adsorption process, thereby beneficial to the γ-spectrometry of the metals enriched on MgO. [ABSTRACT FROM AUTHOR]

Spleen lymphocytes from ependymoblastoma hosting mice show specific receptors for isologuous cytoplasmic tumor proteins. Binding demonstrated by immunofluorescence was observed on lymphocytes from mice transplanted either subcutaneously or intracranially with the tumor model. As control, normal brain soluble proteins did not show binding. [ABSTRACT FROM AUTHOR]

Distemper virus titrations of 2-, 4-, 5-, and 10-fold steps, each using 5, 8, 10, and 15 C.A.M.'s per dilution, showed differences in the standard error of the median effective dose and mean regression coefficients. For reasonable results, a titration using 2-fold dilutions and eight C.A.M.'s per dilution, repeated three times, was selected as a design for laboratory use. Probit analysis of the titration showed a MED of 4.7±0.076 log virus dilution. A 95% confidence interval of the median effective dose was 0.30 log virus dilution with 81% of the endpoints occurring 0.10 log virus dilution on either side of the median effective dose. The regression coefficient was −1.6±0.29 probits per log virus dilution when a 1.5 log virus dilution range was used, with the median effective dose occurring midway in the virus dilution range. The regression was valid (t=5.6, t=3.2) and the data fitted the line (χ=∼0.0, χ=7.8). [ABSTRACT FROM AUTHOR]

Lectin binding, endo-chitinase binding and enzymatic degradation studies show that the epidermal cuticle of the bony fish Paralipophrys trigloides (Blenniidae) is chitinous. This is the first evidence that a vertebrate species possesses a chitinous tissue. Recently a Xenopus gene has been identified which has significant sequence similarity to the catalytic domain of yeast chitin synthase III, a chitin producing enzyme. Taken together these two findings imply that chitin synthesis capability may be a basic vertebrate feature. [ABSTRACT FROM AUTHOR]

We report a 47-year-old bone marrow transplant recipient with haemorrhagic cystitis caused by adenovirus successfully treated with ganciclovir. This is the first report on the use of ganciclovir for the successful treatment of adenoviral infection. Shell vial culture may be more sensitive than conventional culture in the detection of adenovirus in such patients. [ABSTRACT FROM AUTHOR]

Several corrections to the article "Predicting children's behavior during dental treatment under oral sedation" that was published in a previous issue of 2016 is presented.