Effect of motilin on gastric distension sensitive neurons in arcuate nucleus and gastric motility in rat

BACKGROUND

Intestinal motilin is known to stimulate gastrointestinal (GI) motility and the arcuate nucleus (Arc) of hypothalamus is shown to be involved in the regulation of GI motility.

METHODS

Single unit discharges in the Arc were recorded extracellularly by implantation of a force transducer into the stomach in rats, to evaluate the effect of motilin on gastric motility. Projection of nerve fiber and expression of motilin were observed by retrograde tracer deposits of Fluoro-Gold (FG) and fluo-immunohistochemistry staining.

KEY RESULTS

65.5% of neurons in Arc responded to gastric distension (GD), 55.6% of which showed excitation (GD-E), and 44.4% showed inhibition (GD-I). After GD, the firing rate of GD-E neurons significantly increased (P<0.01), but decreased for GD-I neurons (P<0.01). Most of both GD-E and GD-I neurons were activated by motilin (P<0.05). The frequency and amplitude of gastric contractions significantly increased by administration of motilin in Arc with a dose dependent manner (P<0.05-0.01). However, pretreatment with GM109 could abolish the responses of neurons and excitatory effect of gastric motility induced by motilin. Motilin immunoreactive neurons were increased in Arc via gastric distention (P<0.05). Motilin/FG-labeled neurons were detected in hypothalamus paraventricular nucleus (PVN).

CONCLUSIONS & INFERENCES

Our findings suggest that motilin neurons in Arc may accept peripheral somatosensory afferent inputs from gastric mechanoreceptors of the stomach, and also may acts as a stimulatory factor in Arc to regulate gastric motility via some inferior nucleus relay pathway. The results provide insight into the role of Arc in the control of digestion mediated via motilin.

Chinese ischemic stroke subclassification

Accurate classification of stroke has significant impact on patient care and conduction of stroke clinical trials. The current systems such as TOAST, SSS-TOAST, Korean TOAST, and A–S–C–O have limitations. With the advent of new imaging technology, there is a need to have a more accurate stroke subclassification system. Chinese ischemic stroke subclassification (CISS) system is a new two step system aims at the etiology and then underlying mechanism of a stroke. The first step classify stroke into five categories: large artery atherosclerosis (LAA), including atherosclerosis of aortic arch and intra-/extracranial large arteries, cardiogenic stroke, penetrating artery disease, other etiology, and undetermined etiology. The second step is to further classify the underlying mechanism of ischemic stroke from the intracranial and extracranial LAA into the parent artery (plaque or thrombosis) occluding penetrating artery, artery-to-artery embolism, hypoperfusion/impaired emboli clearance, and multiple mechanisms. Although clinical validation of CISS is being planned, CISS is an innovative system that offers much more detailed information on the pathophysiology of a stroke.

Abstract P1-09-02: Health Care Costs Incurred by Post-Menopausal Women with Hormone-Positive Breast Cancer Following the Initial Diagnosis of Metastasis

Objectives: Estimate the healthcare costs before and after progression to chemotherapy in a population of post-menopausal hormone-receptor positive (HR+) metastatic breast cancer (mBC) patients. Methods:

This retrospective cohort study used claims from a large national US health plan. Females age 55 to 63 were selected if they were diagnosed with metastatic breast cancer between 7/1/01 and 12/31/07, and initiated hormonal therapy before progressing to chemotherapy. Incident metastatic patients were followed until the earliest of disenrollment from the health plan, death, or 12/31/08. The pre-chemotherapy period was defined as the period between the incident diagnosis of metastases and the earlier of the initiation of chemotherapy and the end of the study period. Among the subset of patients with use of chemotherapy, the post-chemotherapy period was defined as the time following chemotherapy initiation until the end of the study. Inflation-adjusted costs were examined during the pre-and post-chemotherapy periods. Descriptive analyses were supplemented with Kaplan-Meier sample-average to adjust for variable follow-up time and censoring. Results:

A total of 1,202 patients were identified, 366 (30.4%) of whom progressed to chemotherapy following the onset of metastases. The mean age ± SD was 58.9 ± 2.6 years.

On average, patients incurred $79,139 (SD± $121,489) per year in total health care costs before the initiation of chemotherapy and $132,786 (SD± $117,635) after the initiation of chemotherapy. In the pre-chemotherapy and post-chemotherapy phases, medical expenses were $74,149 (SD± $119,838) and $120,942 (SD± $116,225) per patient-year, respectively, while outpatient medications filled at a retail pharmacy or through a mail system pharmacy cost $4,990 (SD± $5033) and $11,843 (SD± $14,431) per patient-year, respectively. On average, most of the observed medical expenses were incurred during outpatient visits with $44,405 (SD± $55,710) and $87,299 (SD± $75,360) per patient-year in the pre-and post-chemotherapy phases respectively. Inpatient stays accounted for $27,147 (SD± $101,405) and $30,118 (SD± $73,216) per patient-year during the pre-and post-chemotherapy periods, respectively. ER visits cost an average of $424 (SD± $1,871) per patient-year during the pre-chemotherapy period and $1,274 (SD± $5,686) per patient-year during the post chemotherapy period, on average. During the post-chemotherapy period, combined costs for both inpatient and outpatient chemotherapy were $33,559 (SD± $38,692) per patient-year on average, and costs for services associated with supportive care for chemotherapy during the same time period accounted for an additional $18,676 (SD± $30,281) per patient-year on average. After adjusting for variable follow-up times, cumulative total healthcare costs were $54,725, $73,107, and $84,200 for years one, two, and three of the pre-chemotherapy period, respectively, and were $92,639, $148,228, and $176,163 during the same portions of the post-chemotherapy period. Conclusions:

Post-menopausal HR+ mBC patients incur significant healthcare costs both before and after progressing to chemotherapy. The main cost driver was medical costs in both the pre-and post-chemotherapy periods.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-09-02.

Lateral movement of soil fumigants 1,3-dichloropropene and chloropicrin from treated agricultural fields

The soil fumigants 1,3-dichloropropene (1,3-D) and chloropicrin (CP) are often used for controlling soil-borne plant pathogens and parasitic nematodes before reestablishing new vineyards and orchards. To evaluate crop safety and environmental risks with the replant fumigation, four field experiments were performed over 2 yr to examine 1,3-D and CP lateral movement away from the treated fields. Shank injection with or without a virtually impermeable film (V1F) was used in two vineyard fumigation experiments, and spot drip application without tarp cover was used in two orchard experiments. Results showed that 1,3-D and CP gases moved laterally to 6 m from the treated fields when the fumigants were applied by shank injection. The maximum 1,3-D or CP soil gas concentration at 6 m was approximately 10 ng cm(-3) when the fumigated plot was not cover with a tarp. With VIF, the measured maximum concentration increased to approximately 100 ng cm(-3). In the spot drip application, maximum 1,3-D and CP gas concentrations reached approximately 100 ng cm(-3) but at 1.5 m radial distance from the point of fumigant injection.

Use of anticholinergics and the risk of cognitive impairment in an African American population

BACKGROUND

Anticholinergic properties of certain medications often go unrecognized, and are frequently used by the elderly population. Few studies have yet defined the long-term impact of these medications on the incidence of cognitive impairment.

METHODS

We report a 6-year longitudinal, observational study, evaluating 1,652 community-dwelling African American subjects over the age of 70 years who were enrolled in the Indianapolis-Ibadan Dementia Project between 2001 and 2007 and who had normal cognitive function at baseline. The exposure group included those who reported the baseline use of possible or definite anticholinergics as determined by the Anticholinergic Cognitive Burden scale. Our main outcome measure was the incidence of cognitive impairment, defined as either dementia or cognitive impairment not dementia, or poor performance on a dementia screening instrument during the follow-up period.

RESULTS

At baseline, 53% of the population used a possible anticholinergic, and 11% used a definite anticholinergic. After adjusting for age, gender, educational level, and baseline cognitive performance, the number of definite anticholinergics was associated with an increased risk of cognitive impairment (odds ratio [OR] 1.46, 95% confidence interval [CI] 1.07-1.99; p = 0.02), whereas the number of possible anticholinergics at baseline did not increase the risk (OR 0.96, 95% CI 0.85-1.09; p = 0.55). The risk of cognitive impairment among definite anticholinergic users was increased if they were not carriers of the APOE epsilon4 allele (OR 1.77, 95% CI 1.03-3.05; p = 0.04).

CONCLUSIONS

Limiting the clinical use of definite anticholinergics may reduce the incidence of cognitive impairment among African Americans.

Vegetation changes and partitioning of selenium in 4-year-old constructed wetlands treating agricultural drainage

The knowledge of selenium (Se) partitioning in treatment wetlands and wetland vegetation management are essential for long-term effective operation of constructed wetlands treating Se-laden agricultural tile-drainage in central California. In this field study, samples from different compartments of treatment wetlands were collected and the vegetation change in each wetland cell was examined four years after the wetland's inception. The results showed that saltgrass (Distichlis spicata) and rabbitfoot grass (Polypogon monspeliensis) were less competitive than cattail (Typha latifolia) and saltmarsh bulrush (Scirpus robustus). Over 90% of the wetland cell originally vegetated with saltgrass or rabbitfoot grass was occupied by invasive plants--i.e., when invasive species were not controlled in the wetlands. More Se was likely found in sediments from vegetated regions, compared to the unvegetated areas of the wetland cell. Particularly, rhizosphere sediments accumulated about 4-fold more Se than non-rhizosphere sediments. Among the total Se retained in the wetland 90% of the total Se was partitioned in the top 10-cm layer of sediment. The Se accumulation in plant materials accounted for about 2% of the total Se mass retained in each wetland cell. This field study demonstrated that wetland plants play significant roles in the treatment of Se-laden agricultural drainage.

Immunogenicity of Ra1A and its tissue-specific expression in hepatocellular carcinoma

In order to understand the immunogenicity of a tumor-associated antigen (TAA), Ras family small GTP binding protein (Ra1A) in hepatocellular carcinoma (HCC), autoantibody responses to RalA were evaluated by enzyme-linked immunosorbent assay (ELISA), Western blotting and indirect immunofluorescence assay in sera from patients with HCC and sera from normal individuals. Immunohistochemistry (IHC) study with tissue array slides was also performed to analyze protein expression profiles of RalA in HCC and control tissues. This study demonstrated that RalA had a relative higher frequency of autoantibody response in HCC (20.1%) compared to liver cirrhosis (3.3%), chronic hepatitis (0%), and normal individuals sera (0%). RalA also showed a stepwise increased expression from normal liver tissues (26.7%), liver cirrhosis tissues (45.0%) to HCC tissues (63.3%). Sensitivity and specificity of anti-RalA antibody in detection of HCC was 20.1% and 99.3%, respectively. The data suggested that RalA might contribute to liver malignant transformation, and could be used as a potential tumor marker in HCC detection.

Nanoscratch resistance of human tooth enamel treated by Nd: YAG laser irradiation

The purpose of this study was to investigate the friction behaviour of human tooth enamel irradiated by Nd:YAG laser. Forty specimens were randomly divided into four groups, and received the Nd:YAG laser irradiation with different energy densities (without irradiation; 20, 40, and 80 J/cm2). Subsequently, nano-scratch tests were conducted on the treated enamel surfaces, with progressive loads from 0.1 to 80 mN. The morphologies of the treated enamel surfaces and the scratch scars were observed via a field emission scanning electron microscope and an AMBIOS XP-2 stylus profilometer. The results indicated that the Nd:YAG laser promoted slight morphological alterations under a lower energy density (20 J/cm2), but different morphologies occurred under a higher energy density (40 and 80 J/cm2). The irradiated enamel surfaces had inferior nano-scratch resistance, and the nano-scratch resistance decreased as the energy density increased. Nd:YAG laser irradiation decreased the nano-scratch resistance of the enamel. The main damage mechanisms of the irradiated enamel under nano-scratch consisted of brittle delaminations and formation of cracks.

Genomic full length sequence of HLA-Cw*030301, identified by cloning and sequencing

Genomic full length sequence of human leukocyte antigen (HLA)-Cw*030301 that differs from Cw*030401 by two-nucleotide exchange at nt 473 (G>A) in exon 2 and nt 3033 (G>C) in 3'UTR, was identified by cloning and sequencing from a male Chinese donor.

A novel HLA-Cw*04 allele, Cw*04010103, identified by genomic full length cloning and sequencing

A novel human leukocyte antigen-Cw*04 allele, Cw*04010103, was identified by genomic full length cloning and sequencing from a male Chinese donor. It differs from the closest related allele Cw*04010101 by one nucleotide exchange at nt 1111 (G>A) in intron 3.

Lifespan influences on mid- to late-life cognitive function in a Chinese birth cohort

OBJECTIVE

To explore factors throughout the lifespan that influence cognition in midlife to late life.

METHODS

We conducted a retrospective birth cohort study of 2,062 individuals born during 1921-1954 in Beijing, China. In 2003-2005, birth records were abstracted, and participants then 50-82 years old received standardized examinations for health, cognition, and socio-environmental measures. Using cumulative logit models, we assessed adjusted relative effects of prenatal, early life, and adult factors on mid- to late-life cognition.

RESULTS

Most prenatal factors were associated with mid- to late-life cognition in the unadjusted models. However, when childhood and adult factors were sequentially added to the models, the impact of prenatal factors showed successive attenuation in effect size, and became insignificant. In contrast, early life factors remained significantly associated with mid- to late-life cognition even after full life-course adjustments. Specifically, those whose fathers had laborer vs professional occupations (odds ratio [OR](Laborer) 1.74; 95% confidence interval [CI]: 1.25-2.42) had poorer cognitive outcomes, while individuals who drank milk daily in childhood (OR 0.65; 95% CI: 0.54-0.80), had more years of education (OR(10-12 years) 0.60; 95% CI: 0.45-0.81; OR(13+ yrs) 0.29; 95% CI: 0.23-0.38), and were taller adults (OR(height > or = SD) 0.65; 95% CI: 0.49-0.86) had better cognition. The high prenatal risk infants had similar patterns with a trend toward a stronger association between cognition and socioenvironmental factors.

CONCLUSION

Mid- to late-life cognition is influenced by factors over the entire lifespan with the greatest impact coming from early life exposures. Nutrition, education, social, and family environment in early life may have a long-term impact on cognition in developing countries.

Spot fumigation: fumigant gas dispersion and emission characteristics

Reducing emissions of volatile organic compounds (VOCs) from fumigant pesticides is mandatory in California, especially in "nonattainment areas" like the San Joaquin Valley that do not meet federal air quality standards. A two-year field study was conducted to examine the feasibility of site-specific fumigant application only at future tree sites with dramatically reduced amounts of fumigant chemicals on an orchard basis. Soil gas distribution and atmospheric emission of 1,3-dichloropropene and chloropicrin were measured after applying InLine using subsurface drip irrigation. It was predicted that except in the surface 20 cm of soil, satisfactory pest control could be achieved within a 15 cm radius from the injection point. Also, at radial distances of 15-51 cm from the point of fumigant injection, effective nematode control may be achieved. Cumulative atmospheric emission of the fumigants was estimated to be 18-23% of the applied active ingredients in plots that had been cover cropped with Sudan grass and 2-6% in plots that had remained bare for several months before treatment. Considering the significantly small amount of fumigant used on an orchard basis, the spot drip fumigation may achieve a 10-fold reduction in atmospheric VOCs load from fumigant pesticides.

p27 deregulation by Skp2 overexpression induced by the JAK2V617 mutation

Janus kinase 2 (JAK2) V617F mutation has been regarded as the major cause of myeloproliferative disorders (MPD). However, the mechanisms of abnormal cell growth by JAK2V617F have not been elucidated. In this study, cell cycle regulatory protein expression was analyzed using JAK2V617F-Ba/F3 and mock-Ba/F3. JAK2V617F-Ba/F3, but not mock-Ba/F3, showed IL-3 independent cell growth and constitutive STATs activation. Deregulation of p27(Kip1), the cell cycle regulator at the G1 to S transition, was observed in JAK2V617F-Ba/F3 but not in mock-control. p27(Kip1) deregulation was not due to p27(Kip1) mRNA level but due to high Skp2 expression, a subunit of ubiquitin E3 ligase, through the STAT binding in the Skp2 promoter. Like JAK2V617F overexpression, constitutively active STAT5 or STAT3 induced aberrant p27(Kip1) expression of Ba/F3 cells. Similar findings were observed in BCR/ABL-transfected Ba/F3. Our results elucidate the regulatory mechanism by which JAK2V617F modulates Skp2 gene expression through the STAT transcription factors.

Length control and sharpening of carbon nanotube scanning probe microscope tips using carbon nanotube "nanoknife"

Through nanomanipulation inside scanning electron microscope, a carbon nanotube scanning probe microscope tip was made by connecting a carbon nanotube with a silicon atomic force microscope tip. The carbon nanotube scanning probe microscope tip was then tailored to the desired length and end structure by a "nanoknife" which is a carbon nanotube adhered to a metal tip. Through mapping the same carbon nanotube on SiO2 substrate, it was found that the lateral resolution of the carbon nanotube tips can be improved significantly through sharpening the tip ends, and the sharpened carbon nanotube tips had better performance than commercial silicon tips.