27 research outputs found
Parallel transport on a Lie 2-group bundle over a Lie groupoid along Haefliger paths
We prove a Lie 2-group torsor version of the well-known one-one
correspondence between fibered categories and pseudofunctors. Consequently, we
obtain a weak version of the principal Lie group bundle over a Lie groupoid.
The correspondence also enables us to extend a particular class of principal
2-bundles to be defined over differentiable stacks. We show that the
differential geometric connection structures introduced in the authors'
previous work, combine nicely with the underlying fibration structure of a
principal 2-bundle over a Lie groupoid. This interrelation allows us to derive
a notion of parallel transport in the framework of principal 2-bundles over Lie
groupoids along a particular class of Haefliger paths. The corresponding
parallel transport functor is shown to be smooth. We apply our results to
examine the parallel transport on an associated VB-groupoid
Structural, microstructural, and thermal characterizations of a chalcopyrite concentrate from the Singhbhum shear zone, India
The structural and morphological characterizations of a chalcopyrite concentrate, collected from the Indian Copper Complex, Ghatshila, India, were carried out by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The concentrate powder was composed mainly of free chalcopyrite and low quartz in about 3:1 weight ratio. The particle size was about 100 mu m. Spectroscopic studies (FTIR, Raman, UV-visible) of the concentrate supported the XRD findings, and also revealed a marginal oxidation of the sulfide phase. The energy band gap of the sulfide was found to be 3.4 eV. Differential thermal analysis and thermogravimetry of the concentrate showed a decomposition of chalcopyrite at 658 K with an activation energy of 208 kJ center dot mol(-1), and two successive structural changes of silica at 848 K and 1145 K
Oxidative Dimerization of 2‑Oxindoles Promoted by KO<sup><i>t</i></sup>Bu‑I<sub>2</sub>: Total Synthesis of (±)-Folicanthine
A ‘<i>transition-metal-free</i>’ oxidative
coupling of 2-oxindoles has been demonstrated in the presence of 1.2
equiv each of potassium <i>tert</i>-butoxide and iodine.
The method yields a diverse range of structurally different homo-
and heterodimerized 2-oxindoles bearing vicinal all-carbon quaternary
centers of great synthetic importance. A radical-driven pathway has
been tentatively proposed
Cytologically Diagnosed Ovarian Carcinoma Turned Out To Be a Case of Chronic Ectopic Pregnancy
Background and ndash; The diagnosis of chronic ectopic pregnancy is often difficult as there is a shortage of literature in which this disease is diagnosed as an entity separate from the condition of acute ecopic pregnancy. Experience with fine needle aspiration cytology in chronic ectopic pregnancy is not reported previously.
Case - A 29-year-old para 3 woman presented with lower abdominal pain and irregular menstruation since two months Transvaginal ultrasonography showed a well defined heterogenous, solid-cystic right adnexal mass with normal serum beta HCG , and mildly elevated CA 125 level . Fine needle aspiration cytology from the mass suggested possibility of serous cyst adenocarcinoma. Abdominal hysterectomy with bilateral salpingo-oophorectomy and infra-colic omentectomy was done. Pathological findings were consistent with chronic ectopic pregnancy.
Conclusion and ndash;It is possible to retrieve trophoblastic cells through fine needle aspiration even after 2 months of tubal rupture and this experience can be utilized to diagnose chronic ectopic pregnancy preoperatively. [J Interdiscipl Histopathol 2014; 2(2.000): 116-120
Transition-Metal Free Oxidative Alkynylation of 2‑Oxindoles with Ethynylbenziodoxolone (EBX) Reagents
We report an efficient direct alkynylations
of 3-alkyl/aryl 2-oxindoles
employing ethynyl-1,2-benziodoxol-3Â(1H)-one (EBX) to afford a wide
variety of 3-alkynyl-3-alkyl/aryl 2-oxindole under transition-metal
free condition. In addition to activated carbonyl compounds <i>viz</i>. 2-oxindole-3-alkylcarboxylates, this direct alkynylations
protocol works efficiently on 3-alkyl/aryl 2-oxindols as well thereby
widening the scope even further. Eventually, a Pd(0)-catalyzed asymmetric
decarboxylative allylation of few products is shown to furnish synthetically
viable enantioenriched 2-oxindoles with C-3 quaternary stereocenters
Biomimetic Total Syntheses of Clavine Alkaloids
Biomimetic total syntheses of either
enantiomers of a number of
ergot alkaloids, chanoclavine I (<b>1b</b>), chanoclavine I
aldehyde (<b>1c</b>), pyroclavine (<b>1e</b>), festuclavine
(<b>1f</b>), pibocin A (<b>1g</b>), 9-deacetoxyfumigaclavine
C (<b>1h</b>), and fumigaclavine G (<b>1i</b>), have been
achieved from <i>seco</i>-agroclavine (<b>1a</b>).
The advanced intermediate for <i>seco</i>-agroclavine (<b>1a</b>) was synthesized via a key thiourea-catalyzed intramolecular
nitronate addition onto α,β-unsaturated ester
Role of pleural biopsy in etiological diagnosis of pleural effusion
<b>Background:</b> Pleural effusion remains the most common manifestation of pleural pathology. Sometimes it is difficult to differentiate between tubercular and malignant pleural effusion in spite of routine biochemical and cytological examination of pleural fluid. <b>Aims:</b> This study aims to evaluate the role of pleural biopsy to determine the etiology of pleural effusion and to correlate it with the biochemical and cytological parameters of pleural fluid. <b>Settings and Design:</b> Seventy two consecutive patients of pleural effusion were selected from the out patient and indoor department of a tertiary hospital of Kolkata. It was a prospective and observational study conducted over a period of one year. <b>Materials and Methods:</b> Biochemical, cytological and microbiological evaluation of pleural fluid was done in all cases. Those with exudative pleural effusions underwent pleural biopsy by Abram′s needle. Subsequently, the etiology of effusion was determined. <b>Results:</b> Malignancy was the most common etiology, followed by tuberculosis. Pleural biopsy was done in 72 patients. Pleural tissue was obtained in 62 cases. Malignancy was diagnosed in 24, tuberculosis in 20 and non-specific inflammation in 18, on histopathological examination. Out of 20 histological proven tuberculosis cases adenosine de-aminase (ADA) was more than 70 u/l in 11 cases. <b>Conclusions:</b> In our study, malignancy is more common than tuberculosis, particularly in elderly. When thoracoscope is not available, pleural fluid cytology and pleural biopsy can give definite diagnosis. Pleural fluid ADA ≥ 70 u/l is almost diagnostic of tuberculosis, where pleural biopsy is not recommended
Arabinosylated Lipoarabinomannan Skews Th2 Phenotype towards Th1 during Leishmania Infection by Chromatin Modification: Involvement of MAPK Signaling
The parasitic protozoan Leishmania donovani is the causative organism for visceral leishmaniasis (VL) which persists in the
host macrophages by deactivating its signaling machinery resulting in a critical shift from proinflammatory (Th1) to an antiinflammatory
(Th2) response. The severity of this disease is mainly determined by the production of IL-12 and IL-10 which
could be reversed by use of effective immunoprophylactics. In this study we have evaluated the potential of Arabinosylated
Lipoarabinomannan (Ara-LAM), a cell wall glycolipid isolated from non pathogenic Mycobacterium smegmatis, in regulating
the host effector response via effective regulation of mitogen-activated protein kinases (MAPK) signaling cascades in
Leishmania donovani infected macrophages isolated from BALB/C mice. Ara-LAM, a Toll-like receptor 2 (TLR2) specific ligand,
was found to activate p38 MAPK signaling along with subsequent abrogation of extracellular signal–regulated kinase (ERKs)
signaling. The use of pharmacological inhibitors of p38MAPK and ERK signaling showed the importance of these signaling
pathways in the regulation of IL-10 and IL-12 in Ara-LAM pretreated parasitized macrophages. Molecular characterization of
this regulation of IL-10 and IL-12 was revealed by chromatin immunoprecipitation assay (CHIP) which showed that in Ara-
LAM pretreated parasitized murine macrophages there was a significant induction of IL-12 by selective phosphorylation and
acetylation of histone H3 residues at its promoter region. While, IL-10 production was attenuated by Ara-LAM pretreatment
via abrogation of histone H3 phosphorylation and acetylation at its promoter region. This Ara-LAM mediated antagonistic
regulations in the induction of IL-10 and IL-12 genes were further correlated to changes in the transcriptional regulators
Signal transducer and activator of transcription 3 (STAT3) and Suppressor of cytokine signaling 3 (SOCS3). These results
demonstrate the crucial role played by Ara-LAM in regulating the MAPK signaling pathway along with subsequent changes
in host effector response during VL which might provide crucial clues in understanding the Ara-LAM mediated protection
during Leishmania induced pathogenesis