133 research outputs found
Blood, Brain and Now Bone â Learning More About an Often Overlooked Pathogen
INTRODUCTION:
Arcanobacterium haemolyticum (previously Corynebacterium haemolyticum), a facultative anaerobe, Gram positive rod was first isolated from United States servicemen and indigenous populations of the South Pacific in 1946. Early reported cases detailed A. haemolyticum as a causative pathogen for exudative pharyngitis (most commonly in adolescents) and cutaneous infections. Osteomyelitis caused by A. haemolyticum has been described in less than five cases in the literature. Here, we describe our experience in diagnosing patient with osteomyelitis caused by A. haemolyticum.
CASE REPORT:
A 30-year-old man with a history of peripheral neuropathy, diabetic foot ulcers, methicillin-resistant S. aureus osteomyelitis and amputation of the left second distal phalanx, who presented with a malodorous and painful plantar ulcer. Physical exam showed erythematous, edematous distal left foot and 3cm x 0.5cm x 2mm plantar ulcer with necrotic tissue and serosanguinous drainage. Labs revealed elevated inflammatory markers. Left foot X-ray showed previous amputation of the second distal phalanx, soft tissue swelling and indistinctness of the cortex of the 3rd distal phalanx, consistent with osteomyelitis. He underwent intraoperative debridement and resection of the distal second metatarsophalangeal joint. Intraoperative wound and bone cultures grew aerobic gram-positive bacilli with few diphtheroid. Histochemical analyses confirmed Arcanobacterium haemolyticum three days from the procedure. He was discharged home on a six-week course of IV clindamycin with wound VAC.
DISCUSSION:
A. haemolyticum infections can be separated epidemiologically into two distinct subsets. Healthy adolescents presenting with upper respiratory tract infections and immunocompromised patients presenting with systemic serious infection. It is often overlooked or misdiagnosed due to its slow growth and features similar to other pathogens. Initial microbiology reads that show mixed flora, including gram-positive rods and diphtheroid bacilli, are part of the normal flora of the skin. A. haemolyticumâs distinct colony features typically are seen after 72 hours of incubation.
CONCLUSION:
Gram-positive organisms, including Staphylococcus aureus, b hemolytic Streptococcus, and coagulase-negative Staphylococcus are the most common cause of osteomyelitis. A. haemolyticum is another gram-positive organism and the causative agent of osteomyelitis that is less commonly known. However, differentiation of A. haemolyticum from other gram-positive organisms is essential for a proper management and appropriate antibiotic treatment
Measuring Inner Speech Objectively and Subjectively in Aphasia
Background: Many people with aphasia and people without brain
injury talk to themselves in their heads, i.e., have âinner speech.â
Inner speech may be more preserved compared with spoken
speech for some people with aphasia and may serve a variety of
functions (e.g., emotion regulation), which motivates us to provide
a high-fidelity characterization of it. Researchers have used multiple
methods to measure this internal phenomenon in the past, which
we combine here for the first time in a single study.
Aims: We compare performance between individuals with and
without aphasia on inner speech tasks that assess inner speech âinthe-
momentâ to general subjective impressions of inner speech to
tease apart the relationship of aphasia severity to inner speech.
Methods and Procedures: Twenty people with mild-moderate
aphasia and twenty neurotypical controls completed several inner
speech tasks, including objective silent rhyme judgements (picture,
written, and auditory), subjective reports of inner speech during
naming, and subjective rating scales about inner speech experience
more generally.
Outcomes and Results: In-the-moment inner speech during silent
rhyming tasks was associated with aphasia severity only for picture
and written rhyming but not auditory rhyming. In-the-moment
inner speech reports during silent naming were not associated
with aphasia severity, nor were the subjective ratings about general
inner speech experience. Individuals with and without aphasia
demonstrated a variety of subjective general inner speech experiences,
demonstrating heterogeneity of this phenomenon more
broadly.
Conclusions: Methods of measuring inner speech complement
each other and speak to different facets of the inner speech phenomenon,
and clinicians and researchers must carefully choose the
method(s) that will provide the information about inner speech that
they desire
Clinical outcomes after reverse shoulder arthroplasty in patients 60 years old and younger; Medium-term results
BACKGROUND: Reverse total shoulder arthroplasty (RTSA) has been well-described as a surgical solution to manage rotator cuff tear arthropathy in elderly, low demand paitents. As experience has increased along with improvements in technique and implant design, RTSA has become increasingly used to manage more varied pathologic conditions of the shoulder in younger, more active patients. This study evaluates outcomes in a consecutive series of patients aged 60 years old and younger after undergoing RTSA.
METHODS: There were 94 shoulders in 89 patients enrolled. Mean age of the cohort was 54.8 (range 18-60 years). Surgical indications included rotator cuff tear arthropathy, irreparable rotator cuff tear without arthritis, glenohumeral arthritis with erosive glenoid deformity, inflammatory arthropathy, proximal humerus fracture nonunion/malunion and failed prior shoulder arthroplasty. Sixty-one shoulders (70%) had undergone at least one prior surgery. Of these, 6 shoulders (6% of total cohort) had a prior failed arthroplasty. Clinical outcomes (American Shoulder and Elbow Surgeons score, Western Ontario Osteoarthritis of the Shoulder index; visual analog scale pain), radiographic outcomes and complications were analyzed and assessed for correlation with patient demographic factors.
RESULTS: The mean follow-up for this cohort was 4.9 years (range 2-12 years). Subjects experienced improvements in ASES score and pain (
CONCLUSION: With medium-term follow-up, RTSA is a reliable and predictable operation to manage various pathologic conditions in patients aged 60 years or less. Patients predictably experience significant improvements in pain and range of motion while assuming a modest complication risk. Long-term study is needed to understand potential for late complications or implant failure
Untargeted metagenomics protocol for the diagnosis of infection from CSF and tissue from sterile sites
Metagenomic next-generation sequencing (mNGS) is an untargeted technique capable of detecting all microbial nucleic acid within a sample. This protocol outlines our wet laboratory method for mNGS of cerebrospinal fluid (CSF) specimens and tissues from sterile sites. We use this method routinely in our clinical service, processing 178 specimens over the past 2.5 years in a laboratory that adheres to ISO:15189 standards. We have successfully used this protocol to diagnose multiple cases of encephalitis and hepatitis
Tambora and the Mackerel Year: Phenology and Fisheries During an Extreme Climate Event
Global warming has increased the frequency of extreme climate events, yet responses of biological and human communities are poorly understood, particularly for aquatic ecosystems and fisheries. Retrospective analysis of known outcomes may provide insights into the nature of adaptations and trajectory of subsequent conditions. We consider the 1815 eruption of the Indonesian volcano Tambora and its impact on Gulf of Maine (GoM) coastal and riparian fisheries in 1816. Applying complex adaptive systems theory with historical methods, we analyzed fish export data and contemporary climate records to disclose human and piscine responses to Tamboraâs extreme weather at different spatial and temporal scales while also considering sociopolitical influences. Results identified a tipping point in GoM fisheries induced by concatenating social and biological responses to extreme weather. Abnormal daily temperatures selectively affected targeted fish speciesâalewives, shad, herring, and mackerelâaccording to their migration and spawning phenologies and temperature tolerances. First to arrive, alewives suffered the worst. Crop failure and incipient famine intensified fishing pressure, especially in heavily settled regions where dams already compromised watersheds. Insufficient alewife runs led fishers to target mackerel, the next species appearing in abundance along the coast; thus, 1816 became the âmackerel year.â Critically, the shift from riparian to marine fisheries persisted and expanded after temperatures moderated and alewives recovered. We conclude that contingent human adaptations to extraordinary weather permanently altered this complex system. Understanding how adaptive responses to extreme events can trigger unintended consequences may advance long-term planning for resilience in an uncertain future
Evaluation of a new culture medium for isolation of nontuberculous mycobacteria from environmental water samples
Nontuberculous mycobacteria (NTM) are waterborne pathogens commonly found in building water systems where they are a primary concern to vulnerable patient populations and can cause severe disease. The recovery of NTM from environmental samples can be a laborious undertaking and current pre-treatment methods and selective media lack sensitivity. We explored the use of the highly selective Rapidly Growing Mycobacteria (RGM) medium for culturing NTM from environmental water samples compared to existing methods. In total, 223 environmental water samples, including potable and non-potable water, were cultured for NTM using three culture media. In addition to direct culture on RGM medium, each sample was cultured on Middlebrook 7H10 medium and Mitchison 7H11 medium after pre-treatment with 0.2M KCl-HCl. Additionally, 33 distinct species of NTM were inoculated onto RGM medium and 7H10 medium in parallel to directly compare their growth. The use of RGM medium alone without pre-treatment provided a sensitivity (91%) comparable to that offered by culture on both 7H10 and 7H11 with acid pretreatment (combined sensitivity; 86%) with significantly less overgrowth and interference from other organisms on RGM medium. The average concentration of NTM observed on RGM medium alone was comparable to or greater than the NTM concentration on either medium alone or combined. Thirty-three species were examined in parallel and all tested strains of 27 of these species successfully grew on RGM medium, including 19 of 21 from the CDCâs healthcare-associated infections species list. RGM medium was successful at recovering environmental NTM without a pre-treatment, greatly reducing labor and materials required to process samples. Simplification of culture processing for environmental NTM will allow for a better assessment of their presence in building water systems and the potential for reduced exposure of susceptible populations
Galaxy Clustering in Early SDSS Redshift Data
We present the first measurements of clustering in the Sloan Digital Sky
Survey (SDSS) galaxy redshift survey. Our sample consists of 29,300 galaxies
with redshifts 5,700 km/s < cz < 39,000 km/s, distributed in several long but
narrow (2.5-5 degree) segments, covering 690 square degrees. For the full,
flux-limited sample, the redshift-space correlation length is approximately 8
Mpc/h. The two-dimensional correlation function \xi(r_p,\pi) shows clear
signatures of both the small-scale, ``fingers-of-God'' distortion caused by
velocity dispersions in collapsed objects and the large-scale compression
caused by coherent flows, though the latter cannot be measured with high
precision in the present sample. The inferred real-space correlation function
is well described by a power law, \xi(r)=(r/6.1+/-0.2 Mpc/h)^{-1.75+/-0.03},
for 0.1 Mpc/h < r < 16 Mpc/h. The galaxy pairwise velocity dispersion is
\sigma_{12} ~ 600+/-100 km/s for projected separations 0.15 Mpc/h < r_p < 5
Mpc/h. When we divide the sample by color, the red galaxies exhibit a stronger
and steeper real-space correlation function and a higher pairwise velocity
dispersion than do the blue galaxies. The relative behavior of subsamples
defined by high/low profile concentration or high/low surface brightness is
qualitatively similar to that of the red/blue subsamples. Our most striking
result is a clear measurement of scale-independent luminosity bias at r < 10
Mpc/h: subsamples with absolute magnitude ranges centered on M_*-1.5, M_*, and
M_*+1.5 have real-space correlation functions that are parallel power laws of
slope ~ -1.8 with correlation lengths of approximately 7.4 Mpc/h, 6.3 Mpc/h,
and 4.7 Mpc/h, respectively.Comment: 51 pages, 18 figures. Replaced to match accepted ApJ versio
The Fifth Data Release of the Sloan Digital Sky Survey
This paper describes the Fifth Data Release (DR5) of the Sloan Digital Sky
Survey (SDSS). DR5 includes all survey quality data taken through June 2005 and
represents the completion of the SDSS-I project (whose successor, SDSS-II will
continue through mid-2008). It includes five-band photometric data for 217
million objects selected over 8000 square degrees, and 1,048,960 spectra of
galaxies, quasars, and stars selected from 5713 square degrees of that imaging
data. These numbers represent a roughly 20% increment over those of the Fourth
Data Release; all the data from previous data releases are included in the
present release. In addition to "standard" SDSS observations, DR5 includes
repeat scans of the southern equatorial stripe, imaging scans across M31 and
the core of the Perseus cluster of galaxies, and the first spectroscopic data
from SEGUE, a survey to explore the kinematics and chemical evolution of the
Galaxy. The catalog database incorporates several new features, including
photometric redshifts of galaxies, tables of matched objects in overlap regions
of the imaging survey, and tools that allow precise computations of survey
geometry for statistical investigations.Comment: ApJ Supp, in press, October 2007. This paper describes DR5. The SDSS
Sixth Data Release (DR6) is now public, available from http://www.sdss.or
Spectroscopic Target Selection in the Sloan Digital Sky Survey: The Main Galaxy Sample
We describe the algorithm that selects the main sample of galaxies for
spectroscopy in the Sloan Digital Sky Survey from the photometric data obtained
by the imaging survey. Galaxy photometric properties are measured using the
Petrosian magnitude system, which measures flux in apertures determined by the
shape of the surface brightness profile. The metric aperture used is
essentially independent of cosmological surface brightness dimming, foreground
extinction, sky brightness, and the galaxy central surface brightness. The main
galaxy sample consists of galaxies with r-band Petrosian magnitude r < 17.77
and r-band Petrosian half-light surface brightness < 24.5 magnitudes per square
arcsec. These cuts select about 90 galaxy targets per square degree, with a
median redshift of 0.104. We carry out a number of tests to show that (a) our
star-galaxy separation criterion is effective at eliminating nearly all stellar
contamination while removing almost no genuine galaxies, (b) the fraction of
galaxies eliminated by our surface brightness cut is very small (0.1%), (c) the
completeness of the sample is high, exceeding 99%, and (d) the reproducibility
of target selection based on repeated imaging scans is consistent with the
expected random photometric errors. (abridged)Comment: 42 pages, including 12 figures. Accepted for September 2002 A
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