3,226 research outputs found
Utility of synovial biopsy
Synovial biopsies, gained either by blind needle biopsy or minimally invasive arthroscopy, offer additional information in certain clinical situations where routine assessment has not permitted a certain diagnosis. In research settings, synovial histology and modern applications of molecular biology increase our insight into pathogenesis and enable responses to treatment with new therapeutic agents to be assessed directly at the pathophysiological level. This review focuses on the diagnostic usefulness of synovial biopsies in the light of actual developments
Large scale analytic calculations in quantum field theories
We present a survey on the mathematical structure of zero- and single scale
quantities and the associated calculation methods and function spaces in higher
order perturbative calculations in relativistic renormalizable quantum field
theories.Comment: 25 pages Latex, 1 style fil
Honey bee foraging distance depends on month and forage type
To investigate the distances at which honey bee foragers collect nectar and pollen, we analysed 5,484 decoded waggle dances made to natural forage sites to determine monthly foraging distance for each forage type. Firstly, we found significantly fewer overall dances made for pollen (16.8 %) than for non-pollen, presumably nectar (83.2 %; P < 2.2 × 10−23). When we analysed distance against month and forage type, there was a significant interaction between the two factors, which demonstrates that in some months, one forage type is collected at farther distances, but this would reverse in other months. Overall, these data suggest that distance, as a proxy for forage availability, is not significantly and consistently driven by need for one type of forage over the other
A randomized trial to compare exercise treatment methods for patients after total knee replacement: Protocol paper Rehabilitation, physical therapy and occupational health
Background: Although the outcome of total knee replacement (TKR) is favorable, surgery alone fails to resolve the functional limitations and physical inactivity that existed prior to surgery. Exercise is likely the only intervention capable of improving these persistent limitations, but exercises have to be performed with intensity sufficient to promote significant changes, at levels that cannot be tolerated until later stages post TKR. The current evidence is limited regarding the effectiveness of exercise at a later stage post TKR. To that end, this study aims to compare the outcomes of physical function and physical activity between 3 treatment groups: clinic-based individual outpatient rehabilitative exercise during 12 weeks, community-based group exercise classes during 12 weeks, and usual medical care (wait-listed control group). The secondary aim is to identify baseline predictors of functional recovery for the exercise groups. Methods/Design: This protocol paper describes a comparative effectiveness study, designed as a 3-group single-blind randomized clinical trial. Two hundred and forty older adults who underwent TKR at least 2 months prior will be randomized into one of the three treatment approaches. Data will be collected at baseline, 3 months, and 6 months. The wait-listed control group will be randomized to one of the 2 exercise groups after 6 months of study participation, and will complete a 9-month follow-up. Primary outcome is physical function measured by the Western Ontario and McMaster Universities Osteoarthritis Index Physical Function Subscale (WOMAC-PF). Physical function is also measured by performance-based tests. Secondary outcomes include performance-based tests and physical activity assessed by a patient-reported survey and accelerometry-based physical activity monitors. Exploratory outcomes include adherence, co-interventions, attrition, and adverse events including number of falls. Linear mixed models will be fitted to compare the changes in outcome across groups. Logistic regression will identify patient characteristics that predict functional recovery in the exercise groups. Instrumental variable methods will be used to estimate the efficacy of the interventions in the presence of non-compliance. Discussion: Results will inform recommendations on exercise programs to improve physical function and activity for patients at the later stage post TKR and help tailor interventions according with patients' characteristics. Trial registration: ClinicalTrials.gov Identifier NCT02237911
The Ecm11-Gmc2 complex promotes synaptonemal complex formation through assembly of transverse filaments in budding yeast
During meiosis, homologous chromosomes pair at close proximity to form the synaptonemal complex (SC). This association is mediated by transverse filament proteins that hold the axes of homologous chromosomes together along their entire length. Transverse filament proteins are highly aggregative and can form an aberrant aggregate called the polycomplex that is unassociated with chromosomes. Here, we show that the Ecm11-Gmc2 complex is a novel SC component, functioning to facilitate assembly of the yeast transverse filament protein, Zip1. Ecm11 and Gmc2 initially localize to the synapsis initiation sites, then throughout the synapsed regions of paired homologous chromosomes. The absence of either Ecm11 or Gmc2 substantially compromises the chromosomal assembly of Zip1 as well as polycomplex formation, indicating that the complex is required for extensive Zip1 polymerization. We also show that Ecm11 is SUMOylated in a Gmc2-dependent manner. Remarkably, in the unSUMOylatable ecm11 mutant, assembly of chromosomal Zip1 remained compromised while polycomplex formation became frequent. We propose that the Ecm11-Gmc2 complex facilitates the assembly of Zip1 and that SUMOylation of Ecm11 is critical for ensuring chromosomal assembly of Zip1, thus suppressing polycomplex formation
Sister Mary Joseph's Nodule at a University Teaching Hospital in Northwestern Tanzania: A Retrospective Review of 34 cases.
Sister Mary Joseph's nodule is a metastatic tumor deposit in the umbilicus and often represents advanced intra-abdominal malignancy with dismal prognosis. There is a paucity of published data on this subject in our setting. This study was conducted to describe the clinicopathological presentation and treatment outcome of this condition in our environment and highlight challenges associated with the care of these patients, and to proffer solutions for improved outcome. This was a retrospective study of histologically confirmed cases of Sister Mary Joseph's nodule seen at Bugando Medical Centre between March 2003 and February 2013. Data collected were analyzed using descriptive statistics. A total of 34 patients were enrolled in the study. Males outnumbered females by a ratio of 1.4:1. The vast majority of patients (70.6%) presented with large umbilical nodule > 2 cm in size. The stomach (41.1%) was the most common location of the primary tumor. Adenocarcinoma (88.2%) was the most frequent histopathological type. Most of the primary tumors (52.9%) were poorly differentiated. As the disease was advanced and metastatic in all patients, only palliative therapy was offered. Out of 34 patients, 11 patients died in the hospital giving a mortality rate of 32.4%. Patients were followed up for 24 months. At the end of the follow-up period, 14(60.9%) patients were lost to follow-up and the remaining 9 (39.1%) patients died. Patients survived for a median period of 28 weeks (range, 2 to 64 weeks). The nodule recurred in 6 (26.1%) patients after complete excision. Sister Mary Joseph's nodule of the umbilicus is not rare in our environment and often represents manifestation of a variety of advanced intra-abdominal malignancies. The majority of the patients present at a late stage and many with distant metastases. The patient's survival is very short leading to a poor outcome. Early detection of primary cancer at an early stage may improve the prognosis
Pinning quantum phase transition for a Luttinger liquid of strongly interacting bosons
One of the most remarkable results of quantum mechanics is the fact that
many-body quantum systems may exhibit phase transitions even at zero
temperature. Quantum fluctuations, deeply rooted in Heisenberg's uncertainty
principle, and not thermal fluctuations, drive the system from one phase to
another. Typically, the relative strength of two competing terms in the
system's Hamiltonian is changed across a finite critical value. A well-known
example is the Mott-Hubbard quantum phase transition from a superfluid to an
insulating phase, which has been observed for weakly interacting bosonic atomic
gases. However, for strongly interacting quantum systems confined to
lower-dimensional geometry a novel type of quantum phase transition may be
induced for which an arbitrarily weak perturbation to the Hamiltonian is
sufficient to drive the transition. Here, for a one-dimensional (1D) quantum
gas of bosonic caesium atoms with tunable interactions, we observe the
commensurate-incommensurate quantum phase transition from a superfluid
Luttinger liquid to a Mott-insulator. For sufficiently strong interactions, the
transition is induced by adding an arbitrarily weak optical lattice
commensurate with the atomic granularity, which leads to immediate pinning of
the atoms. We map out the phase diagram and find that our measurements in the
strongly interacting regime agree well with a quantum field description based
on the exactly solvable sine-Gordon model. We trace the phase boundary all the
way to the weakly interacting regime where we find good agreement with the
predictions of the 1D Bose-Hubbard model. Our results open up the experimental
study of quantum phase transitions, criticality, and transport phenomena beyond
Hubbard-type models in the context of ultracold gases
IFNβ Protects Neurons from Damage in a Murine Model of HIV-1 Associated Brain Injury.
Infection with human immunodeficiency virus-1 (HIV-1) causes brain injury. Type I interferons (IFNα/β) are critical mediators of any anti-viral immune response and IFNβ has been implicated in the temporary control of lentiviral infection in the brain. Here we show that transgenic mice expressing HIV-1 envelope glycoprotein 120 in their central nervous system (HIVgp120tg) mount a transient IFNβ response and provide evidence that IFNβ confers neuronal protection against HIVgp120 toxicity. In cerebrocortical cell cultures, neuroprotection by IFNβ against gp120 toxicity is dependent on IFNα receptor 1 (IFNAR1) and the β-chemokine CCL4, as IFNAR1 deficiency and neutralizing antibodies against CCL4, respectively, abolish the neuroprotective effects. We find in vivo that IFNβ mRNA is significantly increased in HIVgp120tg brains at 1.5, but not 3 or 6 months of age. However, a four-week intranasal IFNβ treatment of HIVgp120tg mice starting at 3.5 months of age increases expression of CCL4 and concomitantly protects neuronal dendrites and pre-synaptic terminals in cortex and hippocampus from gp120-induced damage. Moreover, in vivo and in vitro data suggests astrocytes are a major source of IFNβ-induced CCL4. Altogether, our results suggest exogenous IFNβ as a neuroprotective factor that has potential to ameliorate in vivo HIVgp120-induced brain injury
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