68 research outputs found
Oral and Pharyngeal Cancer Control through Continuing Education
A standardized continuing education course was developed to determine if behavior in dental practices could be modified to improve office participation in oral and pharyngeal cancer control through early detection and tobacco-use cessation
Vacation studies for deaf children
This paper discusses means of rehabilitation for hearing impaired children during the summer
Oral and Pharyngeal Cancer Control and Early Detection
Sixty-four standardized continuing education courses were given for dentists throughout the ten public health districts of the USA to determine if certain behaviors regarding oral and pharyngeal cancer (OPC) control could be modified. Questionnaires were obtained at baseline and at 6 months along with matched control groups. One thousand eight hundred two general dentists participated at baseline and 988 at a 6-month questionnaire follow-up. Analysis of the data indicated that continuing education courses had a positive influence on participants’ oral cancer attitudes, knowledge, and behavior that potentially could make a difference on prevention, early detection, and ultimately OPC control
Chandra Observations of the QSO Pair Q2345+007: Binary Quasar or Massive Dark Lens?
The components of the wide (7.3") separation quasar pair Q2345+007A,B
(z=2.15) have the most strikingly similar optical spectra seen to date (Steidel
& Sargent 1991) yet no detected lensing mass, making this system the best
candidate known for a massive (1e14 Msun) dark matter lens system. Here we
present results from a 65ksec Chandra observation designed to investigate
whether it is a binary quasar or a gravitational lens. We find no X-ray
evidence for a lensing cluster to a (0.5-2keV) flux limit of 2e-15 cgs, which
is consistent with lensing only for a reduced baryon fraction. Using the
Chandra X-ray observations of the quasars themselves, together with new and
published optical measurements, we use the observed emission properties of the
quasars for further tests between the lens and binary hypotheses. Assuming
similar line-of-sight absorption to the images, we find that their X-ray
continuum slopes are inconsistent (Gamma_A=2.30 and Gamma_B=0.83) as are their
X-ray to optical flux ratios. The probability that B suffers absorption
sufficient to account for these spectral differences is negligible. We present
new optical evidence that the flux ratio of the pair is variable, so the
time-delay in a lens scenario could cause some of the discrepancies. However,
adequately large variations in overall spectral energy distribution are rare in
individual QSOs. All new evidence here weighs strongly toward the binary
interpretation. Q2345+007 thus may represent the highest redshift example known
of interaction-triggered but as-yet unmerged luminous AGN.Comment: 15 pages, Latex, emulateapj style, including 3 tables and 5 figures.
Accepted Feb 1, 2002 for publication in ApJ Main Journal. See also
http://hea-www.harvard.edu/~pgreen/Papers.htm
Swallowing dysfunction in cancer patients
Purpose Dysphagia (swallowing dysfunction) is a debilitating, depressing, and potentially life-threatening complication in cancer patients that is likely underreported. The present paper is aimed to review relevant dysphagia literature between 1990 and 2010 with a focus on assessment tools, prevalence, complications, and impact on quality of life in patients with a variety of different cancers, particularly in those treated with curative chemoradiation for head and neck cancer. Methods The literature search was limited to the English language and included both MEDLINE/PubMed and EMBASE. The search focused on papers reporting dysphagia as a side effect of cancer and cancer therapy. We identified relevant literature through the primary literature search and by articles identified in references. Results A wide range of assessment tools for dysphagia was identified. Dysphagia is related to a number of factors such as direct impact of the tumor, cancer resection, chemotherapy, and radiotherapy and to newer therapies such as epidermal growth factor receptor inhibitors. Concomitant oral complications such as xerostomia may exacerbate subjective dysphagia. Most literature focuses on head and neck cancer, but dysphagia is also common in other types of cancer. Conclusions Swallowing impairment is a clinically relevant acute and long-term complication in patients with a wide variety of cancers. More prospective studies on the course of dysphagia and impact on quality of life from baseline to long-term follow-up after various treatment modalities, including targeted therapies, are needed
Environments of galaxies in groups within the supercluster-void network
Majority of all galaxies reside in groups of less than 50 member galaxies.
These groups are distributed in various large-scale environments from voids to
superclusters. Evolution of galaxies is affected by the environment in which
they reside. Our aim is to study the effects that the local group scale and the
supercluster scale environment have on galaxies. We use a luminosity-density
field to determine density of the large-scale environment of galaxies in groups
of various richness. We calculate fractions of different types of galaxies in
groups with richnesses up to 50 member galaxies and in different large-scale
environments from voids to superclusters. The fraction of passive elliptical
galaxies rises and the fraction of star-forming spiral galaxies declines when
the richness of a group of galaxies rises from two to approximately ten
galaxies. On the large scale, the passive elliptical galaxies become more
numerous than star-forming spirals when the environmental density grows to the
density level typical for superclusters. The large-scale environment affects
the level of these fractions in groups: galaxies in equally rich groups are
more likely to be elliptical in supercluster environments than in lower
densities. The crossing point, where the number of passive and star-forming
galaxies is equal, happens in groups with lower richness in superclusters than
in voids. Galaxies in low-density areas require richer groups to evolve from
star-forming to passive. Groups in superclusters are on average more luminous
than groups in large-scale environments with lower density. Our results suggest
that the evolution of galaxies is affected by both, by the group in which the
galaxy resides, and by its large-scale environment. Galaxies in lower-density
regions develop later than galaxies in similar mass groups in high-density
environments.Comment: 10 pages, 9 figures. Published in A&A. Language corrected 9th Oct
201
Lysine120 Interactions with p53 Response Elements can Allosterically Direct p53 Organization
p53 can serve as a paradigm in studies aiming to figure out how allosteric perturbations in transcription factors (TFs) triggered by small changes in DNA response element (RE) sequences, can spell selectivity in co-factor recruitment. p53-REs are 20-base pair (bp) DNA segments specifying diverse functions. They may be located near the transcription start sites or thousands of bps away in the genome. Their number has been estimated to be in the thousands, and they all share a common motif. A key question is then how does the p53 protein recognize a particular p53-RE sequence among all the similar ones? Here, representative p53-REs regulating diverse functions including cell cycle arrest, DNA repair, and apoptosis were simulated in explicit solvent. Among the major interactions between p53 and its REs involving Lys120, Arg280 and Arg248, the bps interacting with Lys120 vary while the interacting partners of other residues are less so. We observe that each p53-RE quarter site sequence has a unique pattern of interactions with p53 Lys120. The allosteric, DNA sequence-induced conformational and dynamic changes of the altered Lys120 interactions are amplified by the perturbation of other p53-DNA interactions. The combined subtle RE sequence-specific allosteric effects propagate in the p53 and in the DNA. The resulting amplified allosteric effects far away are reflected in changes in the overall p53 organization and in the p53 surface topology and residue fluctuations which play key roles in selective co-factor recruitment. As such, these observations suggest how similar p53-RE sequences can spell the preferred co-factor binding, which is the key to the selective gene transactivation and consequently different functional effects
Personal Papers (MS 80-0002)
Letter from Sol Silverman to Daniel W. Kempner enclosing a check for $14
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