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Retinal Artery and Vein Occlusions Successfully Treated with Hyperbaric Oxygen
We present six cases of central retinal artery occlusion (CRAO) and central retinal vein occlusion (CRVO) that we recently treated with hyperbaric oxygen (HBO2). Patients in three of the six cases, including the CRVO case, experienced near to complete restoration of their vision. Another case had marked improvement. Our findings are similar to other case studies with approximately 65-70% improvement in patients treated for CRAO. Physicians should be aware that rapid referral of CRAO and CRVO patients to HBO2 is efficacious. Such patients should be placed on 100% oxygen by non-rebreather mask as soon as the diagnosis is suspected, pending transportation to HBO2
Successful Treatment of Radiation-Induced Colitis and Enteritis with Hyperbaric Oxygen Therapy
Introduction
Previously irradiated tissue is characterized by changes including decreased vascularity, impaired cellular proliferation, and local hypoxia consistent with fibroblastic atrophy which can persist long after radiation therapy. Hyperbaric oxygen therapy has been shown to be beneficial in the treatment of complications arising from these late effects of radiation on normal tissue through enhancing fibroblast proliferation, collagen maturation, stem cell recruitment, and angiogenesis.
Methods
We report on three patients with debilitating radiation enterocolitis causing issues including recurrent bowel obstruction, anorexia requiring total parenteral nutrition, pain, diarrhea, fecal incontinence, dehydration, and malnutrition.
Results
In all three cases marked improvement was the outcome with hyperbaric treatment.
Conclusion
Hyperbaric oxygen therapy should be routinely considered in the treatment of radiation-induced enteritis or colitis
Hyperbaric Oxygen Therapy for Cerebral Radiation Necrosis Secondary to Stereotactic Radiation: A Case Series
Introduction: Stereotactic radiosurgery (SRS) is an excellent option for the treatment of numerous central nervous system diseases. There exist several forms of SRS, including gamma-knife surgery (GKS) and cyber-knife surgery. The most significant complication of SRS is the delayed effects of therapeutic radiation, also known as radionecrosis. The current treatment options for radionecrosis have a significant side effect profile and posit challenges for medical management. More recently, hyperbaric oxygen therapy (HBO2) has emerged as an option for treatment with minimal side effects.
Methods: We present a retrospective case series examining ten patients treated with HBO2 after receiving radiotherapy. Of these cases, six were treated with GKS, two were treated with cyber-knife surgery, and two with Intensity-modulated radiation therapy (IMRT).
Results: In all ten cases, the patients reported significant improvement in clinical symptoms.
Conclusions: These cases demonstrate the efficacy of HBO2 as a treatment for cerebral radionecrosis
Genetic characterization of clinical and environmental Vibrio parahaemolyticus from the Northeast USA reveals emerging resident and non-indigenous pathogen lineages
Gastric infections caused by the environmentally transmitted pathogen, Vibrio parahaemolyticus, have increased over the last two decades, including in many parts of the United States (US). However, until recently, infections linked to shellfish from the cool northeastern US waters were rare. Cases have risen in the Northeast, consistent with changes in local V. parahaemolyticus populations toward greater abundance or a shift in constituent pathogens. We examined 94 clinical isolates from a period of increasing disease in the region and compared them to 200 environmental counterparts to identify resident and non-indigenous lineages and to gain insight into the emergence of pathogenic types. Genotyping and multi-locus sequence analysis (MLSA) of clinical isolates collected from 2010 to 2013 in Massachusetts, New Hampshire, and Maine revealed their polyphyletic nature. Although 80% of the clinical isolates harbored the trh hemolysin either alone or with tdh, and were urease positive, 14% harbored neither hemolysin exposing a limitation for these traits in pathogen detection. Resident sequence type (ST) 631 strains caused seven infections, and show a relatively recent history of recombination with other clinical and environmental lineages present in the region. ST34 and ST674 strains were each linked to a single infection and these strain types were also identified from the environment as isolates harboring hemolysin genes. Forty-two ST36 isolates were identified from the clinical collection, consistent with reports that this strain type caused a rise in regional infections starting in 2012. Whole-genome phylogenies that included three ST36 outbreak isolates traced to at least two local sources demonstrated that the US Atlantic coastal population of this strain type was indeed derived from the Pacific population. This study lays the foundation for understanding dynamics within natural populations associated with emergence and invasion of pathogenic strain types in the region
Measuring Galaxy Environments with Deep Redshift Surveys
We study the applicability of several galaxy environment measures
(n^th-nearest-neighbor distance, counts in an aperture, and Voronoi volume)
within deep redshift surveys. Mock galaxy catalogs are employed to mimic
representative photometric and spectroscopic surveys at high redshift (z ~ 1).
We investigate the effects of survey edges, redshift precision, redshift-space
distortions, and target selection upon each environment measure. We find that
even optimistic photometric redshift errors (\sigma_z = 0.02) smear out the
line-of-sight galaxy distribution irretrievably on small scales; this
significantly limits the application of photometric redshift surveys to
environment studies. Edges and holes in a survey field dramatically affect the
estimation of environment, with the impact of edge effects depending upon the
adopted environment measure. These edge effects considerably limit the
usefulness of smaller survey fields (e.g. the GOODS fields) for studies of
galaxy environment. In even the poorest groups and clusters, redshift-space
distortions limit the effectiveness of each environment statistic; measuring
density in projection (e.g. using counts in a cylindrical aperture or a
projected n^th-nearest-neighbor distance measure) significantly improves the
accuracy of measures in such over-dense environments. For the DEEP2 Galaxy
Redshift Survey, we conclude that among the environment estimators tested the
projected n^th-nearest-neighbor distance measure provides the most accurate
estimate of local galaxy density over a continuous and broad range of scales.Comment: 17 pages including 16 figures, accepted to Ap
Use of Whole Genome Phylogeny and Comparisons in the Development of a Multiplex-PCR Assay to Identify Sequence Type 36 Vibrio parahaemolyticus
Vibrio parahaemolyticus sequence type (ST) 36 strains that are native to the Pacific Ocean have recently caused multi-state outbreaks of gastroenteritis linked to shellfish harvested from the Atlantic Ocean. Whole genome comparisons of 295 genomes of V. parahaemolyticus, including several traced to northeastern US sources, were used to identify diagnostic loci: one putatively encoding an endonuclease (prp), and two others potentially conferring O-antigenic properties (cps and flp). The combination of all three loci was present only in one clade of closely-related strains, of ST36, ST59 and one additional unknown sequence type. However, each locus was also identified outside this clade, with prp and flp occurring in only two non-clade isolates, and cps in four. Based on the distribution of these loci in sequenced genomes, prp could identify clade strains with \u3e99% accuracy, but the addition of one more locus would increase accuracy to 100%. Oligonucleotide primers targeting prp and cps were combined in a multiplex PCR method that defines species using the tlh locus, and determines presence of both the tdh and trh hemolysin-encoding genes which are also present in ST36. Application of the method in vitro to a collection of 94 clinical isolates collected over a four year period in three Northeastern US, and 87 environmental isolates, revealed the prp and cps amplicons were only detected in clinical isolates identified as belonging to the ST36-clade, and in no environmental isolates from the region. The assay should improve detection and surveillance, thereby reducing infections
Timing of magnetite formation in basaltic glass: Insights from synthetic analogs and relevance for geomagnetic paleointensity analyses
Absolute paleointensity estimates from submarine basaltic glass (SBG) typically are of high technical quality and accurately reflect the ambient field when known. SBG contains fine-grained, low-Ti magnetite, in contrast to the high-Ti magnetite in crystalline basalt, which has lead to uncertainty over the origin of the magnetite and its remanence in SBG. Because a thermal remanence is required for accurate paleointensity estimates, the timing and temperature of magnetite formation is crucial. To assess these factors, we generated a suite of synthetic glasses with variable oxygen fugacity, cooling rate, and FeO* content. Magnetic properties varied most strongly with crystallinity; less crystalline specimens are similar to natural SBG and have weaker magnetization, a greater superparamagnetic contribution, and higher unblocking temperatures than more crystalline specimens. Thellier-type paleointensity results recovered the correct field within 1σ error with 2 (out of 10) exceptions that likely result from an undetected change in the laboratory field. Unblocking and ordering temperature data demonstrate that low-Ti magnetite is a primary phase, formed when the glass initially quenched. Although prolonged heating at high temperatures (during paleointensity experiments) may result in minor alteration at temperatures \u3c 580°C, this does not appear to impact the accuracy of the paleointensity estimate. Young SBG is therefore a suitable material for paleointensity studies
Effects of open and closed system oxidation on texture and magnetic response of remelted basaltic glass
As part of an experimental and observational study of the magnetic response of submarine basaltic glass (SBG), we have examined, using ion backscattering spectrometry (RBS), transmission and scanning electron microscopy, energy dispersive X-ray spectrometry, and surface X-ray diffraction, the textures wrought by the controlled, open and closed system oxidation of glasses prepared by the controlled environment remelting and quenching of natural SBG. Initial compositions with ~9 wt % FeO* were melted at 1430°C with the oxygen fugacity buffered at fayalite-magnetite-quartz; melts were cooled at a rate of 200°C min−1 near the glass transition (Tg = 680°C). In open system experiments, where chemical exchange is allowed to occur with the surrounding atmosphere, polished pieces of glass were reheated to temperatures both below and above Tg for times 1–5000 h; undercooled melts were oxidized at 900°C and 1200°C for 18 and 20 h, respectively. RBS demonstrates unequivocally that the dynamics of open system oxidation involves the outward motion of network-modifying cations. Oxidation results in formation of a Fe-, Ca-, and Mg-enriched surface layer that consists in part of Ti-free nanometer-scale ferrites; a divalentcation- depleted layer is observed at depths \u3e1 µm. Specimens annealed/oxidized above Tg have magnetizations elevated by 1–2 orders of magnitude relative to the as-quenched material; this does not appear to be related to the surface oxidation. Quenched glass (closed system, i.e., no chemical exchange between sample and atmosphere) exhibits very fine scale chemical heterogeneities that coarsen with time under an electron beam; this metastable amorphous immiscibility is the potential source for the nucleation of ferrites with a wide range of Ti contents, ferrites not anticipated from an equilibrium analysis of the bulk basalt composition
The DEEP2 Galaxy Redshift Survey: Color and Luminosity Dependence of Galaxy Clustering at z~1
We present measurements of the color and luminosity dependence of galaxy
clustering at z~1 in the DEEP2 Galaxy Redshift Survey. Using volume-limited
subsamples in bins of both color and luminosity, we find that: 1) The
clustering dependence is much stronger with color than with luminosity and is
as strong with color at z~1 as is found locally. We find no dependence of the
clustering amplitude on color for galaxies on the red sequence, but a
significant dependence on color for galaxies within the blue cloud. 2) For
galaxies in the range L/L*~0.7-2, a stronger large-scale luminosity dependence
is seen for all galaxies than for red and blue galaxies separately. The
small-scale clustering amplitude depends significantly on luminosity for blue
galaxies, with brighter samples having a stronger rise on scales r_p<0.5 Mpc/h.
3) Redder galaxies exhibit stronger small-scale redshift-space distortions
("fingers of god"), and both red and blue populations show large-scale
distortions in xi(r_p,pi) due to coherent infall. 4) While the clustering
length, r_0, increases smoothly with galaxy color (in narrow bins), its
power-law exponent, gamma, exhibits a sharp jump from the blue cloud to the red
sequence. The intermediate color `green' galaxy population likely includes
transitional galaxies moving from the blue cloud to the red sequence; on large
scales green galaxies are as clustered as red galaxies but show infall
kinematics and a small-scale correlation slope akin to the blue galaxy
population. 5) We compare our results to a semi-analytic galaxy formation model
applied to the Millenium Run simulation. Differences between the data and the
model suggest that in the model star formation is shut down too efficiently in
satellite galaxies.Comment: 28 pages, 17 figures, emulateapj format, accepted to ApJ, updated to
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