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111.
112.
Satyam Alpana Manchanda K Ramya Anju Garg Kaushik Majumdar 《Journal of Radiology Case Reports》2021,15(10):20
Alveolar soft part sarcoma is a rare soft tissue tumor with uncertain histogenesis. It is a slow growing tumor with a high rate of metastasis. The tumor is not easily identified as clinical symptoms are not pronounced. The retroperitoneum is a rare location of tumor, with a few cases published in literature. Surgical excision is the mainstay of treatment. Here we describe a rare case of a large retroperitoneal Alveolar soft part sarcoma in a young female with radiological and histopathological findings. 相似文献
113.
Dhrubajyoti Majumdar A. Frontera Rosa M. Gomila Sourav Das Kalipada Bankura 《RSC advances》2022,12(10):6352
Spontaneous self-assembly is one of the available synthetic routes to achieve structurally versatile and unique crystal complexes with selected metal–ligand combinations in the spirit of pseudohalides. In this endeavour, we designed a novel 1D coordination polymer (CP), [(Cd)(Pb)(L)(η1-NCS)(η1-SCN)]n (1), using a compartmental Salen ligand (H3L) in the presence of NaSCN. The characterization of the CP was accomplished using several spectroscopic techniques: MALDI-TOF, PXRD, SEM, EDX mapping, and single-crystal X-ray crystallography. The CP crystallizes in the monoclinic space group P21/c with Z = 4. SCXRD reveals Cd(ii) and Pb(ii) metal ions fulfilled distorted square pyramidal and hemi-directed coordination spheres. Cd(ii) is placed in the inner N2O2 and heavier Pb(ii) in the outer O4 compartments of the de-protonated form of the ligand [L]2−. Supramolecular interactions in the intricate crystal structure produced attractive molecular architectures of the compound. The flexible aliphatic –OH pendent group coordinates with the Pb(ii) ions. This unique binding further elevates the supramolecular crystal topographies. The supramolecular interactions were authenticated by Hirshfeld surface analysis (HSA). The observation of the recurring unconventional tetrel bonds was rationalized by DFT calculations and surface plots of molecular electrostatic potential (MEP). In the 1D polymeric chain in the complex, the O-atom of the –OH groups shows a tetrel bonding interaction with the Pb atom. We have found that the combination of QTAIM/NCI and QTAIM/ELF plots helps reveal the nature of these contacts. Moreover, the QTAIM/ELF plot determines the donor–acceptor interaction between the O-atom and the Pb atom, establishing the σ-hole. Agreeably, the σ-hole interaction also helps Pb(ii) serve as a Lewis acid in the complex. Finally, spodium and tetrel bonds are formed, possible thanks to a hemi-directional coordination sphere of the Pb atoms in the polymer described.We report σ-hole interaction/spodium/tetrel bonding and other non-covalent interactions in a heteronuclear Pb(ii)–Salen coordination polymer using DFT, HSA, QTAIM/NCI, and QTAIM/ELF plots. The non-covalent interactions predominantly drive the formation of extended architectures. 相似文献
114.
Dear Editor,The eye(other than the respiratory system)is considered an important route of infection of severe acute respiratory syndrome coronavirus 2(SARSCoV-2)that causes Coronavirus disease 2019(COVID-19).Literature has shown that people typically touch their face about 23 times every waking hour~([1]).The eye is rich in the angiotensin-converting enzyme-2 receptor,the SARS-CoV-2 gateway~([2]). 相似文献
115.
Kwak YD Brannen CL Qu T Kim HM Dong X Soba P Majumdar A Kaplan A Beyreuther K Sugaya K 《Stem cells and development》2006,15(3):381-389
Although amyloid beta (Abeta) deposition has been a hallmark of Alzheimer's disease (AD), the absence of a phenotype in the beta amyloid precursor protein (APP) knockout mouse, tends to detract our attention away from the physiological functions of APP. Although much attention has been focused on the neurotoxicity of Abeta, many studies suggest the involvement of APP in neuroplasticity. We found that secreted amyloid precursor protein (sAPP) increased the differentiation of human neural stem cells (hNSCs) in vitro, while an antibody-recognizing APP dose-dependently inhibited these activities. With a high dose of sAPP treatment or wild-type APP gene transfection, hNSCs were differentiated into astrocytes rather than neurons. In vivo, hNSCs transplanted into APP-transgenic mouse brain exhibited glial differentiation rather than neural differentiation. Our results suggest that APP regulates neural stem cell biology in the adult brain, and that altered APP metabolism in Down syndrome or AD may have implications for the pathophysiology of these diseases. 相似文献
116.
The dexamethasone suppression test in chronic alcoholics with and without depression and its relationship to their hepatic status 总被引:1,自引:0,他引:1
Fifty consecutively admitted male alcoholics (mean age = 42.8 +/- 8.5 years) were selected. This study shows objectively that 31/50 chronic alcoholics (62%) were found to be severely depressed (Hamilton Depression Rating Scale (HRS) greater than 22); 12/50 (24%) moderately depressed (HRS = 16-22); and 7/50 (14%) were not depressed (HRS less than 15). According to dexamethasone suppression test (DST) results, 8 out of 50 patients showed escape from suppression with 2 mg dexamethasone while 42/50 showed normal suppression. Depression in alcoholics may be of neurotic type or it may be ethanol-induced reactive depression. Raised cortisol levels and abnormal DST response showed a definite tendency towards normalisation after total abstinence accompanied by clinical improvement of depressive symptomatology. The DST showed improvement on improvement of mood and sleep in these patients during total abstinence. An abnormal DST response in chronic alcoholics seems to be state-related and not trait-dependent; it seems to be a non-specific test for depression in alcoholics. Hepatic status was affected equally in both suppressors and non-suppressors of DST. It is therefore suggested that abnormal DST in alcoholics may be due to the abnormality of the hypothalamo-pituitary-adrenocortical (HPA) axis and not due to abnormal hepatic function or histological status. 相似文献
117.
Link TM Vieth V Stehling C Lotter A Beer A Newitt D Majumdar S 《European radiology》2003,13(4):663-671
The purpose of this study was to compare trabecular bone structure parameters obtained from high-resolution magnetic resonance
(HRMR) and multislice computed tomography (MSCT) images with those determined in contact radiographs from corresponding specimen
sections. High-resolution MR and MSCT images were obtained in 39 distal radius specimens. For HRMR the in-plane spatial resolution
was 0.152×0.153 mm2 with a slice thickness of 0.9 and 0.3 mm using a 3D T1-weighted spin-echo sequence. For MSCT the resolution was 0.247×0.247 mm2 with a collimation of 1 mm. Using a diamond saw, 117 0.9- to 1-mm-thick sections were obtained from these specimens and contact
radiographs were acquired. In the corresponding sections structure parameters analogous to bone histomorphometry were determined.
Significant correlations between MR- and CT-derived structure parameters and those derived from the contact radiographs were
found (p<0.01); r values of up to 0.75 were obtained for HRMR imaging and up to 0.70 for MSCT. On the average, structure parameters
showed higher correlations for the MR- than for the CT-derived data. For the MR data the threshold algorithm used for binarizing
the images substantially affected these correlations. In conclusion, trabecular bone structure parameters assessed in distal
radius HRMR and MSCT images are significantly correlated with those determined in corresponding specimen sections (p<0.01). High-resolution MR-derived structure parameters, however, performed better in the prediction of trabecular bone structure.
Electronic Publication 相似文献
118.
Effects of sequential treatments with chemotherapeutic drugs followed by TRAIL on prostate cancer in vitro and in vivo 总被引:7,自引:0,他引:7
BACKGROUND: Tumor necrosis factor related apoptosis-inducing ligand/Apo2 ligand (TRAIL/Apo-2L) is a novel anticancer agent, capable of inducing apoptosis preferentially in tumor and transformed cells. TRAIL-R1/death receptor (DR)4 and TRAIL-R2/DR5 are members of the tumor necrosis factor (TNF) receptor family, and can be activated by the TRAIL. We examined the clinical potential of chemotherapeutic drugs and TRAIL for the treatment of prostate cancer. METHODS: Prostate and bladder cancer cells were exposed to chemotherapeutic drugs (paclitaxel, vincristine, vinblastine, etoposide, doxorubicin, and camptothecin) and TRAIL. Cell viability was measured by sodium 3'[1-(phenylaminocarbonyl)-3,4-tetrazolium]-bis (4-methoxy-6-nitro) assay; expressions of death receptors and Bcl-2 family members were measured by Western blotting, ELISA and ribonuclease protection assay. PC-3 tumor cells xenografted athymic nude mice were exposed to chemotherapeutic drugs and TRAIL, either alone or in combination, to measure tumor growth and survival of mice. Apoptosis was measured by annexin V-FITC/propidium iodide staining, and terminal deoxynucleotidyltransferase-mediated nick end labeling assay. Caspase-3 activity was measured by the Western blotting and immunohistochemistry. RESULTS: TRAIL induced apoptosis with varying sensitivity. Chemotherapeutic drugs (paclitaxel, vincristine, vinblastine, etoposide, doxorubicin, and camptothecin) significantly augmented TRAIL-induced apoptosis in cancer cells through up-regulation of DR4, DR5, Bax, and Bak, and induction of caspase activation. Mitochondrial pathway enhanced the synergistic interactions between drugs and TRAIL. The sequential treatment of mice with chemotherapeutic drugs followed by TRAIL induced caspase-3 activity, and apoptosis, inhibited angiogenesis, completely eradicated the established tumors, and enhanced survival of mice. CONCLUSIONS: Chemotherapeutic drugs can be used to enhance the therapeutic potential of TRAIL in prostate cancer. 相似文献
119.
Bryan J. PimlottC. Allyson Jones Lauren A. BeaupreD.W.C. Johnston Sumit R. Majumdar 《Archives of gerontology and geriatrics》2011,53(1):90
Low serum albumin may have prognostic value for morbidity and mortality in patients with hip fracture. The primary aim of the study was to evaluate the independent association between low serum albumin (<35 g/l) at hospital admission and short-term (in-hospital) mortality and post-operative complications of patients with hip fracture. We reviewed a prospective population-based cohort of 583 hip fracture patients who had pre-operative albumin values measured at hospital admission in one of the 3 tertiary hospitals in Northern Alberta, Canada. Patients with a primary diagnosis of hip fracture and 65 years or older were included. The primary outcomes were in-hospital mortality and any pre-specified post-operative complication. Mean serum albumin level was 33.8 ± 4.5 g/l (±S.D.), and overall 55% (n = 318) of patients had a low albumin. The in-hospital mortality was 8% (n = 46) and rate of any non-fatal post-operative complication rate was 31/100. Mortality was 11% (n = 35) among those with low albumin levels and 4% (n = 11) for those with normal values (unadjusted odds ratio (OR) 2.86, 95% CI = 1.42-5.74). After multivariate adjustment, the association between low serum albumin and mortality remained large and statistically significant (adjusted OR = 2.44, 95% confidence interval (CI) = 1.17-5.12). Low albumin levels were also significantly associated with post-operative medical complications (adjusted OR = 1.96, 95% CI = 1.36-2.83). We conclude that routine measurement of serum albumin provides valuable prognostic information for treating this frail population. 相似文献
120.
Xiaojuan Li PhD Sharmila Majumdar PhD 《Journal of magnetic resonance imaging : JMRI》2013,38(5):991-1008
Cartilage is one of the most essential tissues for healthy joint function and is compromised in degenerative and traumatic joint diseases. There have been tremendous advances during the past decade using quantitative MRI techniques as a noninvasive tool for evaluating cartilage, with a focus on assessing cartilage degeneration during osteoarthritis (OA). In this review, after a brief overview of cartilage composition and degeneration, we discuss techniques that grade and quantify morphologic changes as well as the techniques that quantify changes in the extracellular matrix. The basic principles, in vivo applications, advantages, and challenges for each technique are discussed. Recent studies using the OA Initiative (OAI) data are also summarized. Quantitative MRI provides noninvasive measures of cartilage degeneration at the earliest stages of joint degeneration, which is essential for efforts toward prevention and early intervention in OA. J. Magn. Reson. Imaging 2013;38:991–1008. © 2013 Wiley Periodicals, Inc. 相似文献