300 research outputs found
M5-brane prongs, string soliton bound states and wall-crossing
We study abelian M5-brane field configurations representing BPS bound states
of self-dual string solitons whose locations correspond to the endlines of
M2-branes ending on the M5-branes. The BPS equations are obtained from
appropriate Bogomolny completion of the effective abelian low energy functional
with two transverse scalars, using two vectors representing the directions
along which these endline strings extend. Then we impose boundary conditions on
the scalars near the string soliton cores. This leads to a molecule-like
equilibrium structure of two non-parallel string solitons at fixed transverse
separations, with the M5-brane "prong" deformations comprising two "spikes",
each shaped like a ridge. The resulting picture becomes increasingly accurate
as one approaches the wall of marginal stability, on which these states decay.
There are various parallels with wall-crossing phenomena for string web
configurations obtained from D3-brane deformations.Comment: Latex, 44pgs, 3 figs, v2: further clarifications adde
Tubercular Osteomyelitis of the Orbit Presenting as Periorbital Cellulitis
Purpose: Osteomyelitis of the orbital bones presenting as an orbital cellulitis is a rare form of extrapulmonary tuberculosis (TB). We report a rare case of tubercular osteomyelitis of the orbital bones presenting as a periorbital cellulitis.
Case Report: A seven-year-old female child presented to our tertiary eye care center with swelling involving the right eyelids and the right cheek for two months. She had been provisionally diagnosed elsewhere as pre-septal cellulitis and had been given oral antibiotics. We clinically diagnosed her as orbital cellulitis, but her non-responsiveness to intravenous antibiotics prompted us to get a contrast enhanced computed tomography (CECT) of the orbit and paranasal sinuses, which was suggestive of tubercular etiology. However, the patient had no foci for TB elsewhere. We used a relatively new, but rapid test, called Cartridge-based Nucleic Acid Amplification Test (CBNAAT) on the pus aspirate which was positive for TB. Thereafter, the patient was started on anti-tubercular treatment to which she responded wonderfully.
Conclusion: A high index of suspicion should be kept for TB infection in cases of orbital cellulitis with unusual clinical behavior in an endemic region such as India
Immune response against M protein-conserved region peptides from prevalent group A Streptococcus in a North Indian population
BackgroundGroup A streptococci (GAS) cause infections with a high prevalence in most developing countries. A GAS vaccine under trial that is based on the amino-terminus of the M protein provides type-specific immunity, and hence seems ineffective in India because of heterogeneous emm types. However, the conserved C-terminal region of the M protein protects against multiple serotypes. In this paper, the immune response generated against the conserved C-repeat region of the M protein was checked in an Indian population to establish their vaccine candidature.MethodsWhen screened for GAS, patients with pharyngitis, rheumatic fever/rheumatic heart disease (RF/RHD), and invasive disease showed heterogeneous emm types, out of which five prevalent types (1-2, 11, 49, 75 and 112) were selected for the study. The C-terminal region of their M proteins showed conserved C1-, C2-, and C3-repeats. The C1-repeat was more diverse and had two different J14-like sequences. Peptides to these C-terminal regions (J14.1 and J14-R6) were designed. Antibodies against these peptides were analyzed using the sera of 130 GAS-infected volunteers.ResultsSerum antibodies were significantly higher in patients with acute rheumatic fever, RHD, and invasive disease than in patients with pharyngitis or the healthy controls. The serum antibodies to these peptides was higher in teenagers and adults than in children.ConclusionResults showed an association between streptococcal disease progression and the age-related development of immunity to the conserved regions. Hence, these peptides could be considered protective in impeding streptococcal infections worldwide
Validation of a noninvasive aMMP-8 point-of-care diagnostic methodology in COVID-19 patients with periodontal disease
Objectives: The aim of this study was to validate an active matrix metalloproteinase (MMP-8) point-of-care diagnostic tool in COVID-19 patients with periodontal disease. Subjects, Materials, and Methods: Seventy-two COVID-19-positive and 30 COVID-19-negative subjects were enrolled in the study. Demographic data were recorded, periodontal examination carried out, and chairside tests run for evaluating the expression of active MMP-8 (aMMP-8) in the site with maximum periodontal breakdown via gingival crevicular fluid sampling as well as via a mouth rinse-based kit for general disease activity. In COVID-19-positive patients, the kits were run again once the patients turned COVID-19 negative. Results: The overall (n = 102) sensitivity/specificity of the mouthrinse-based kits to detect periodontal disease was 79.41%136.76% and that of site-specific kits was 64.71%/55.88% while adjusting for age, gender, and smoking status increased the sensitivity and specificity (82.35%/76.47% and 73.53%/88.24, respectively). Receiver operating characteristic (ROC) analysis for the adjusted model revealed very good area under the ROC curve 0.746-0.869 (p < .001) and 0.740-0.872 (p < .001) (the aMMP-8 mouth rinse and site-specific kits, respectively). No statistically significant difference was observed in the distribution of results of aMMP-8 mouth rinse test (p = .302) and aMMP-8 site-specific test (p = .189) once the subjects recovered from COVID-19. Conclusions: The findings of the present study support the aMMP-8 point-of-care testing (PoCT) kits as screening tools for periodontitis in COVID-19 patients. The overall screening accuracy can be further increased by utilizing adjunctively risk factors of periodontitis. The reported noninvasive, user-friendly, and objective PoCT diagnostic methodology may provide a way of stratifying risk groups, deciding upon referrals, and in the institution of diligent oral hygiene regimens.Peer reviewe
Synaptic and transcriptionally downregulated genes are associated with cortical thickness differences in autism.
Differences in cortical morphology-in particular, cortical volume, thickness and surface area-have been reported in individuals with autism. However, it is unclear what aspects of genetic and transcriptomic variation are associated with these differences. Here we investigate the genetic correlates of global cortical thickness differences (ΔCT) in children with autism. We used Partial Least Squares Regression (PLSR) on structural MRI data from 548 children (166 with autism, 295 neurotypical children and 87 children with ADHD) and cortical gene expression data from the Allen Institute for Brain Science to identify genetic correlates of ΔCT in autism. We identify that these genes are enriched for synaptic transmission pathways and explain significant variation in ΔCT. These genes are also significantly enriched for genes dysregulated in the autism post-mortem cortex (Odd Ratio (OR) = 1.11, Pcorrected  10-14), driven entirely by downregulated genes (OR = 1.87, Pcorrected  10-15). We validated the enrichment for downregulated genes in two independent data sets: Validation 1 (OR = 1.44, Pcorrected = 0.004) and Validation 2 (OR = 1.30; Pcorrected = 0.001). We conclude that transcriptionally downregulated genes implicated in autism are robustly associated with global changes in cortical thickness variability in children with autism
Comparison of two different folic acid doses with methotrexate – a randomized controlled trial (FOLVARI Study)
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