The Dearth of Disability Medical Education and a Partial Solution

Issue: While over one-quarter of adult Americans have a disability, there is a paucity of disability-specific curricula in American medical schools and residency programs. Potential consequences of this educational dearth include persistent inaccessibility of health care facilities and delivery of inequitable health care to individuals with disabilities. Evidence: Several working groups have proposed disability-specific competencies for health professions education and means by which to integrate them into existing curricula. A limited number of medical schools and residency programs have formally introduced disability-specific materials into their curricula. To our knowledge, however, there are no generalist (internal medicine or family medicine) residency programs that offer specialized training in the clinical care of people with disabilities. Implications: Offering generalist physicians the opportunity to acquire the clinical and cognitive skills required to provide thorough and equitable health care to people with disabilities is critically important. There are too few physiatrists to see to their care needs. In this manuscript, we present a novel concentration in an Internal Medicine residency program in the care of individuals with a variety of disabilities. Our hope is that this work will initiate discussions among educational leaders about how to address the lack of graduate medical education-level training in disability care. We also hope it will afford program directors the opportunity to implement similar concentrations and tracks and will eventually produce a generation of generalists who are well-equipped to help care for people with disabilities.

Determination of Vitamins A (Retinol) and E (alpha-Tocopherol) in Foods by Liquid Chromatography: Collaborative Study

A collaborative study was conducted for the determination of vitamins A and E. Existing AOAC liquid chromatographic (LC) methods are suited for specific vitamins A and E analytical applications. This method differs from existing methods in that it can be used to assay samples in all 9 sectors of the food matrix. Standards and test samples are saponified in basic ethanol–water solution, neutralized, and diluted, converting fats to fatty acids and retinol esters and tocopherol esters to retinol and tocopherol, respectively. Retinol and alpha-tocopherol are quantitated on separate LC systems, using UV detection at 313 or 328 nm for retinol, and fluorescence detection (excitation 290 nm, emission 330 nm) for alpha-tocopherol. Vitamin concentrations are calculated by comparison of the peak heights or peak areas of vitamins in test samples with those of standards.

Nondiffusive transport regimes for suprathermal ions in turbulent plasmas

The understanding of the transport of suprathermal ions in the presence of turbulence is important for fusion plasmas in the burning regime that will characterize reactors, and for space plasmas to understand the physics of particle acceleration. Here, three-dimensional measurements of a suprathermal ion beam in the toroidal plasma device TORPEX are presented. These measurements demonstrate, in a turbulent plasma, the existence of subdiffusive and superdiffusive transport of suprathermal ions, depending on their energy. This result stems from the unprecedented combination of uniquely resolved measurements and first-principles numerical simulations that reveal the mechanisms responsible for the nondiffusive transport. The transport regime is determined by the interaction of the suprathermal ion orbits with the turbulent plasma dynamics, and is strongly affected by the ratio of the suprathermal ion energy to the background plasma temperature.

Nondiffusive suprathermal ion transport in simple magnetized toroidal plasmas

We investigate suprathermal ion dynamics in simple magnetized toroidal plasmas in the presence of electrostatic turbulence driven by the ideal interchange instability. Turbulent fields from fluid simulations are used in the nonrelativistic equation of ion motion to compute suprathermal tracer ion trajectories. Suprathermal ion dispersion starts with a brief ballistic phase, during which particles do not interact with the plasma, followed by a turbulence interaction phase. In this one simple system, we observe the entire spectrum of suprathermal ion dynamics, from subdiffusion to superdiffusion, depending on beam energy and turbulence amplitude. We estimate the duration of the ballistic phase and identify basic mechanisms during the interaction phase that determine the dependencies of the character of suprathermal ion dispersion upon the beam energy and turbulence fluctuation amplitude.

The significance of HPV status in patients with anal cancer: A comparative technical analysis

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Background: HPV status is an important prognostic factor for outcome in head and neck cancers, with improved survival noted in HPV-positive vs -negative tumors. However, this effect has not been studied in anal cancer. Challenges exist in defining reliable and methods of detecting the presence of high-risk HPV virus or the expression of HPV-related proteins. Purpose: To determine p16 expression and HPV16 status, in association with HPV subtyping, in pre-treatment anal cancers, and to correlate marker status with clinical outcome.

Methods: This retrospective study evaluated anal cancer patients treated between 1992-2005 with definitive RT or CRT at a single institution (Tom Baker Cancer Centre, Calgary, Canada). HPV subtyping, p16 protein expression via conventional immunohistochemistry (IHC) and automated quantitative IHC (AQUA), and HPV16 in-situ hybridization (CISH) was performed in a subset of patient tumors with sufficient pretreatment tumor specimen. The correlation between results using these different techniques and association of HPV markers with clinical outcome was evaluated.

Results: 89 patients were identified; M:F 1:2; median age 57 years. Median tumor size was 3.5 cm. All patients were treated with radical external beam RT with curative intent; 81% received concurrent chemotherapy. Clinical CR was observed in 73% of patients at 3 months post-treatment. Median OS was 82 months. Of tumor specimens analyzed for HPV subtype, 78% (28/36) were HPV16. Using conventional IHC (DAB), 80% (28/35) of tumors over-expressed p16 (score 3). HPV16 CISH was positive in 81% (34/42). P16 AQUA™ score correlated with HPV16 subtyping, CISH for HPV16, and p16 DAB. With HPV16 subtyping as the gold standard for HPV16 infection, false positive and false negative rates were 8% and 4% with DAB, and 10% and 13% with CISH. In univariate analysis only p16 AQUA score > 244 (upper 15%) was associated with PFS (p= 0.006-95% CI 8.4 [1.8-38.6]) and OS (p= 0.013-95% CI 4.5 [1.4-15]).

Conclusions: p16 expression via quantitative IHC correlates with other methods, including HPV16 subtyping, and appears more reliable for defining HPV16 status than CISH. Only quantitative IHC identified a subset of patients with worse outcome.

No significant financial relationships to disclose.

AMPA receptor subunit GluR1 downstream of D-1 dopamine receptor stimulation in nucleus accumbens shell mediates increased drug reward magnitude in food-restricted rats

Previous findings suggest that neuroadaptations downstream of D-1 dopamine (DA) receptor stimulation in nucleus accumbens (NAc) are involved in the enhancement of drug reward by chronic food restriction (FR). Given the high co-expression of D-1 and GluR1 AMPA receptors in NAc, and the regulation of GluR1 channel conductance and trafficking by D-1-linked intracellular signaling cascades, the present study examined effects of the D-1 agonist, SKF-82958, on NAc GluR1 phosphorylation, intracranial electrical self-stimulation reward (ICSS), and reversibility of reward effects by a polyamine GluR1 antagonist, 1-NA-spermine, in ad libitum fed (AL) and FR rats. Systemically administered SKF-82958, or brief ingestion of a 10% sucrose solution, increased NAc GluR1 phosphorylation on Ser845, but not Ser831, with a greater effect in FR than AL rats. Microinjection of SKF-82958 in NAc shell produced a reward-potentiating effect that was greater in FR than AL rats, and was reversed by co-injection of 1-NA-spermine. GluR1 abundance in whole cell and synaptosomal fractions of NAc did not differ between feeding groups, and microinjection of AMPA, while affecting ICSS, did not exert greater effects in FR than AL rats. These results suggest a role of NAc GluR1 in the reward-potentiating effect of D-1 DA receptor stimulation and its enhancement by FR. Moreover, GluR1 involvement appears to occur downstream of D-1 DA receptor stimulation rather than reflecting a basal increase in GluR1 expression or function. Based on evidence that phosphorylation of GluR1 on Ser845 primes synaptic strengthening, the present results may reflect a mechanism via which FR normally facilitates reward-related learning to re-align instrumental behavior with environmental contingencies under the pressure of negative energy balance.

Development and commercial use of Bollgard cotton in the USA--early promises versus today's reality

Bollgard cotton is the trademark given to a number of varieties of cotton bio-engineered to produce an insecticidal protein from Bacillus thuringiensis (Bt). When produced by the modified cotton plants, this protein controls certain lepidopterous cotton insect pests. Commercially available since 1996, these cotton varieties are purchased under a license agreement in which the growers pay a fee and agree to abide by the terms, which include a 1-year license to use the technology and agreement to participate in an insect resistance management program. Today, Bollgard cotton is grown on more than one-third of all cotton acreage in the USA. This product has reduced cotton production costs and insecticide use by providing an effective alternative to chemical insecticides for the control of tobacco budworm, Heliothis virescens; cotton bollworm, Helicoverpa zea; and pink bollworm, Pectinophora gossypiella. The specificity and safety profile of the Bt protein produced in planta in cotton was maintained. It has retained its selectivity for lepidopterous insects and lacks the characteristics found in potential allergenic proteins. Fiber quality, the agronomic characteristics of the plant and seed composition remain unchanged. New cotton technology is being developed to provide improved insect control and a wider spectrum of activity. These future products could further reduce insecticide use in the production of cotton, while maintaining the high level of safety and reliability that has been demonstrated by five seasons of Bollgard cotton use.

Preliminary investigation of voice onset time production in persons with dysphagia

The purpose of this study was to determine whether voice onset time (VOT) values of persons with dysphagia differed from those of a person with normal swallow function. Five male subjects with dysphagia (average age = 80.6 years) and a control subject (age = 79 years) read 18 consonant-vowel-consonant words in quasi-random order. These syllables began with the voiced and voiceless cognates from the three stop places of articulation (i.e., bilabial, alveolar, and velar). These consonants were followed by the vowels /i/, /a/, and /u/. Digital audio tape recordings were performed and speech was digitized onto disk. Measurements were completed using BLISS software (Mertus J: BLISS User's Manual. Providence: Department of Cognitive and Linguistic Sciences, Brown University, 1989) implemented on a 486 microcomputer. Averages and standard deviations of the VOT measures for the six stop consonants were compared between the two experimental groups. For the dysphagic speakers, average VOT values for voiceless stops were shorter, and there were larger negative VOT values for voiced stops. Standard deviations for the VOT productions pf the dysphagic subjects were smaller. Statistical comparisons showed significant differences between individual dysphagic speakers and the normal control for three of the five subjects. These preliminary data suggest that dysphagia affects the fine motor control required for accurate VOT production in speech.

Chemokine and inflammatory cell response to hypoxia-ischemia in immature rats

Hypoxia-ischemia induces an inflammatory response in the immature central nervous system that may be important for development of brain injury. Recent data implicate that chemoattractant cytokines, chemokines, are involved in the recruitment of immune cells. The aim was to study alpha- and beta-chemokines in relation to the temporal activation of inflammatory cells after hypoxia-ischemia in immature rats. Hypoxia-ischemia was induced in 7-day-old rats (left carotid artery occlusion + 7.7% oxygen). The pups were decapitated at different times after the insult. Immunohistochemistry was used for evaluation of the inflammatory cell response and RT-PCR to analyze the cytokine mRNA and chemokine mRNA expression. A distinct interleukin-1beta and tumor necrosis factor-alpha cytokine expression was found 0-24 h after hypoxia-ischemia that was accompanied by induction of alpha-chemokines (growth related gene and macrophage inflammatory protein-2). In the next phase, the beta2-integrin expression was increased (12 h and onward) and neutrophils transiently invaded the vessels and tissue in the infarct region. The mRNA induction for the beta-chemokines macrophage inflammatory protein-1alpha, macrophage inflammatory protein-1beta, and RANTES preceded the expression of markers for lymphocytes [cluster of differentiation (CD)4, CD8], microglia/macrophages (MHC I), and natural killer cells in the infarct area. The activation of microglia/macrophages, CD4 lymphocytes, and astroglia persisted up to at least 42 d of postnatal age implicating a chronic component of immunoinflammatory activation. The expression of mRNA for alpha- and beta-chemokines preceded the appearance of immune cells suggesting that these molecules may have a role in the inflammatory response to insults in the immature central nervous system.

Possible protective role of growth hormone in hypoxia-ischemia in neonatal rats

Perinatal asphyxia still constitutes a clinical hazard associated with considerable neurologic morbidity. Several growth factors, including insulin-like growth factor-I (IGF-I), have been reported to have a neuroprotective effect in experimental models of hypoxic ischemia (HI). In the present study, we have applied solution hybridization for quantification of the time course for mRNA expression of IGF-I, IGF-I receptor, and growth hormone (GH) receptor after HI in 7-d-old rats. There was a significant increase in IGF-I mRNA in the damaged hemisphere 72 h (1.19 +/- 0.28 vs 0.48 +/- 0.02 amol/microg DNA, p < 0.05) and 14 d (0.61 +/- 0.18 vs 0.19 +/- 0.05 amol/microg DNA, p < 0.05) after HI. In the contralateral hemisphere, both IGF-I and GH receptor mRNA had increased by 14 d after the insult (0.36 +/- 0.042 vs 0.13 +/- 0.011, p < 0.05, and 0.31 +/- 0.013 vs 0.11 +/- 0.004 amol/microg DNA, p < 0.001, respectively). There were no changes in IGF-I receptor mRNA throughout the study period. We have also evaluated the neuroprotective effect of GH after HI in neonatal rats. GH administered s.c. after HI in daily doses of 50 and 100 mg/kg provided a moderate neuroprotection of 20%. These results suggest a role for the GH/IGF-I axis in the neurochemical process leading to HI brain injury.

Cytokine response in cerebrospinal fluid after birth asphyxia

Experimental studies suggest that cytokine-mediated inflammatory reactions are important in the cascade leading to hypoxic-ischemic brain injury. The purpose was to study the content of pro- and antiinflammatory cytokines in cerebrospinal fluid (CSF) of asphyxiated and control infants. Samples of CSF were obtained from 20 infants who fulfilled the criteria of birth asphyxia and from seven newborn control subjects. The concentrations of IL-1beta, IL-8, IL-10, tumor necrosis factor (TNF)-alpha, and granulocyte/monocyte colony-stimulating factor (GM-CSF) were determined with ELISA and of IL-6 using a bioassay. The concentration of IL-6 (pg/mL) was higher in asphyxiated (250, 35-543; median, interquartile range) than in control (0, 0-18) infants (p = 0.001). There was also a significant relationship between IL-6 and the degree of HIE, and between IL-6 and outcome. In addition, the content of IL-8 (pg/mL) was higher (p = 0.009) in the asphyxia group (170, 70-1440), than in the the control group (10, 0-30) and there was an association between IL-8 and degree of HIE. The levels of IL-10, TNF-alpha, GM-CSF, and IL-1beta did not differ between groups. In conclusion, the proinflammatory cytokines IL-6 and IL-8 were markedly elevated in CSF of asphyxiated infants, and the intrathecal levels of these cytokines corresponded to the degree of HIE.

Contextual quick-learning and generalization by humans and machines

In a previous study (1994 Network: Comput. Neural Syst. 5 203-27) we compared human quick-learning and generalization (quick modelling) with that of neural nets (feedforward architectures), symbolic algorithms (decision tree procedures), and pattern classifiers (truth-set descriptors). Those studies raised the question of the role of context in the nature and rapidity of human learning. Here we address that issue in the setting of the same basic experiment (Quinlan classification problem) used for the previous studies. A major implication of our findings is that humans overwhelmingly seek, create, or imagine context in order to provide meaning when presented with abstract or apparently incomplete or contradictory or otherwise untenable situations.

Distinct expression patterns detected within individual tissues by the GAL4 enhancer trap technique

To identify genes that are expressed in specific cell types or tissues during development, we generated enhancer-trap lines in which the yeast transcriptional activator, GAL4, was mobilized throughout the Drosophila genome. The GAL4 lines are part of a two-part system involving GAL4 and its target, the upstream activating sequence (UAS). Detection of GAL4 expression patterns was achieved by crossing individual GAL4 lines with flies carrying the reporter gene lacZ under the transcriptional control of the UAS followed by histochemical and immunocytochemical staining. Here, we present the results of this screen and the characterization of GAL4 lines that show distinct patterns of gene expression during Drosophila development, including embryogenesis, oogenesis, and imaginal disc development. However, we were unable to identify GAL4 lines that were expressed within the germ line or during early embryogenesis. Furthermore, consistent with previous results, we found that the GAL4 enhancer trap technique had a much lower frequency of transposition than has been reported for lacZ enhancer trap screens. Taken together, these results demonstrate both the strengths and weaknesses of the GAL4 enhancer trap technique for identifying unique patterns of gene expression during development.

Green fluorescent protein as a vital marker and reporter of gene expression in Drosophila

We have used the green fluorescent protein (GFP) from the jellyfish Aequorea victoria as a vital marker/reporter in Drosophila melanogaster. Transgenic flies were generated in which GFP was expressed under the transcriptional control of the yeast upstream activating sequence that is recognized by GAL4. These flies were crossed to several GAL4 enhancer trap lines, and expression of GFP was monitored in a variety of tissues during development using confocal microscopy. Here, we show that GFP could be detected in freshly dissected ovaries, imaginal discs, and the larval nervous system without prior fixation or the addition of substrates or antibodies. We also show that expression of GFP could be monitored in intact living embryos and larvae and in cultured egg chambers, allowing us to visualize dynamic changes in gene expression during real time.

Acute toxic exposure to gases from liquid manure

Liquid manure storage is a common component of confinement systems for swine, beef, dairy, and veal operations. A mail questionnaire to a sample of swine producers indicated that more than 85,000 people in Iowa and an estimated 500,000 in the United States work in livestock confinement systems that use liquid manure storage. Deaths and illnesses in people with acute exposure to toxic gases emanating from the liquid manure have been recently reported. This communication reports results of the investigation of six such incidents. Hydrogen sulfide appears to be the main toxic substance involved, and agitation of the liquid manure is important in creating an acutely severely toxic environment. Preventive measures must include worker education and limitation of human exposure through control of environmental and human factors.