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A 32-year-old diabetic male, with a past history of head injury and seizures, presented with a painful swelling over his forehead present for the past three months. Cranial MRI demonstrated the presence of a scalp collection with extradural extension through a bony defect. Biopsy from the area showed caseating necrosis suggestive of tuberculosis. Although the patient failed to return for initiation of anti-tubercular therapy for the next 11 months, the swelling did not progress, and there were no constitutional symptoms. The indolent nature of the swelling prompted re-evaluation and delayed cultures of pus from the collection grew Burkholderia pseudomallei.  相似文献   
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ObjectiveTo determine the relationship between tuberculosis and the degree of immunosuppression as determined by CD4 count. The impact of immunosuppression on the severity of tuberculosis was also studied.MethodsA retrospective analysis was performed in patients newly diagnosed with HIV infection and antiretroviral therapy (ART)-naive patients with known HIV seropositivity. All patients were diagnosed with active tuberculosis between January 2008 and December 2010, based on review of their medical records. Patients on chemoprophylaxis for opportunistic infection were excluded. Pattern and severity of tuberculosis, associated stigmata of immunosuppression, and CD4 counts were noted.ResultsOf 140 patients satisfying the inclusion criteria, 52 had mild tuberculosis with no other evidence of immunosuppression, 52 had tuberculosis of variable severity with associated evidence of immunosuppression, and 36 had severe tuberculosis with no other evidence of immunosuppression. The CD4 count was highest in the first group [(109.2±99.9) cells/μL] and least in the second group [(58.4±39.8) cells/μL], and the difference was statistically significant (P=0.004). No statistical difference was observed in the CD4 count between those with mild tuberculosis and those with severe tuberculosis.ConclusionsIn developing countries with a high prevalence of tuberculosis in the general population, the possibility of incidental tuberculosis in patients with HIV should always be considered. CD4 count does not appear to influence the severity of tuberculosis. The presence of concomitant evidence of immunosuppression in the form of category B and C conditions is indicative of underlying immunosuppression and associated with a significantly lower CD4 count.  相似文献   
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Abstract

The reported paper presents the development of a microwave sensor with a resonant frequency 2.4?GHz. The sensor is also demonstrated in vitro to investigate the variation in its response as a function of glucose concentration. The sensor could be used for the monitoring of blood glucose level in diabetics through non-invasive technology. The approach followed is based on the notion that, change in glucose concentration in the blood affects dielectric properties of blood which in turn produce an impact on reflection properties of the sensor. This effect on response of sensor will be ultimately used to estimate blood glucose concentration. The design specifications considered for the development of sensor are defined in the paper. The experimental setup for in vitro experiment and procedure employed for the investigation of the reflection properties of the sensor as a function of glucose concentration are also discussed in detail. The shift in resonance frequency and the change in the magnitude of the reflection coefficient of proposed sensor have been observed. The reported measurement results are the preliminary results in exploring the implementation of proposed sensor for non-invasive blood glucose monitoring.  相似文献   
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Journal of Digital Imaging - We present a hybrid algorithm to estimate lung nodule malignancy that combines imaging biomarkers from Radiologist’s annotation with image classification of CT...  相似文献   
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Artificial intelligence (AI) applications, in the form of machine learning and deep learning, are being incorporated into practice in various aspects of medicine, including radiation oncology. Ample evidence from recent publications explores its utility and future use in external beam radiotherapy. However, the discussion on its role in brachytherapy is sparse. This article summarizes available current literature and discusses potential uses of AI in brachytherapy, including future directions. AI has been applied for brachytherapy procedures during almost all steps, starting from decision-making till treatment completion. AI use has led to improvement in efficiency and accuracy by reducing the human errors and saving time in certain aspects. Apart from direct use in brachytherapy, AI also contributes to contemporary advancements in radiology and associated sciences that can affect brachytherapy decisions and treatment. There is a renewal of interest in brachytherapy as a technique in recent years, contributed largely by the understanding that contemporary advances such as intensity modulated radiotherapy and stereotactic external beam radiotherapy cannot match the geometric gains and conformality of brachytherapy, and the integrated efforts of international brachytherapy societies to promote brachytherapy training and awareness. Use of AI technologies may consolidate it further by reducing human effort and time. Prospective validation over larger studies and incorporation of AI technologies for a larger patient population would help improve the efficiency and acceptance of brachytherapy. The enthusiasm favoring AI needs to be balanced against the short duration and quantum of experience with AI in limited patient subsets, need for constant learning and re-learning to train the AI algorithms, and the inevitability of humans having to take responsibility for the correctness and safety of treatments.  相似文献   
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The development of novel antitumor agents that have high efficacy in suppressing tumor growth, have low toxicity to nontumor tissues, and exhibit rapid localization in the targeted tumor sites is an ongoing avenue of research at the interface of chemistry, cancer biology, and pharmacology. Supramolecular metal-based coordination complexes (SCCs) have well-defined shapes and geometries, and upon their internalization, SCCs could affect multiple oncogenic signaling pathways in cells and tissues. We investigated the uptake, intracellular localization, and antitumor activity of two rhomboidal Pt(II)-based SCCs. Laser-scanning confocal microscopy in A549 and HeLa cells was used to determine the uptake and localization of the assemblies within cells and their effect on tumor growth was investigated in mouse s.c. tumor xenograft models. The SCCs are soluble in cell culture media within the entire range of studied concentrations (1 nM–5 µM), are nontoxic, and showed efficacy in reducing the rate of tumor growth in s.c. mouse tumor xenografts. These properties reveal the potential of Pt(II)-based SCCs for future biomedical applications as therapeutic agents.Molecular assemblies of nanoscale-size and well-defined geometries have recently emerged as an interesting new paradigm in drug design and drug delivery. To date, liposomes, the self-assembled lipid nanoparticles held together by weak interactions, are among the most widely studied and clinically successful nanoparticle-based drug carriers. Their use allows the drug to achieve sustained plasma levels while encapsulated, with the size preventing the fast clearance by the kidneys that often occurs with the free drug. However, liposomes themselves do not produce a therapeutic effect and their application as drug carriers for medical purposes has often been hindered by poor loading capacity (<5 wt %) and the inability to pass through biological barriers (1, 2). Inorganic and hybrid porous materials, such as molecular organic frameworks (MOFs), have also shown promise due to their higher loading capacities (>25 wt %) (35), but MOFs have poor hydrolytic stability (6, 7). Recent studies on materials from Institut Lavoisier (MIL)-100(Cr) and MIL-100(Fe), however, suggest that MOFs can persist in biologically relevant environments and can act as vehicles for some anticancer and antiviral agents (810). These early findings have prompted further investigations into the biomedical applications of supramolecular coordination complexes (SCCs) (1124). SCCs preserve the attractive properties of MOFs, such as building block modularity (22, 23, 25), yet afford an increased solubility in the biological milieu and lend themselves to small-molecule characterization techniques due to their well-defined structure.Although development of SCCs for biomedical applications is in its infancy, some SCCs, such as trigonal prisms self-assembled from p-cymene and ruthenium-based metal fragments with pyridyl donors, have shown the ability to act as effective carriers of some chemotherapeutic agents (2628). Moreover, a library of cytotoxic to cancer cells p-cymene ruthenium-based polygons and cages has also been developed (11). For biomedical applications, the information about the cellular uptake, delivery of a guest, and metabolism of the drug delivery vehicle is critical, although currently the fate of SCCs in biological environments is not well understood. In a rare report, a systematic investigation of the structural stability of a water-soluble, hexacationic ruthenium-based trigonal prism was performed; however, it was determined that the ruthenium-based trigonal prisms decompose in the presence of amino acids histidine, lysine, and arginine (29).An intriguing approach is the design of tumor-targeted modalities that combine detection and treatment through the self-assembly of emissive, metal-based coordination complexes. Such modalities can be especially valuable as they often do not require photoexcitation to elicit cytotoxicity. Recently Gray, Gross, and Medina-Kauwe and coworkers reported HerGa, a self-assembled tumor-targeted particle that bears the Ga(III)-metalated derivative of the sulfonated corrole (30, 31). The particle, which contained Ga(III)-corrole noncovalently bound to the tumor-targeting cell penetration protein HerPBK10, provided both tumor detection and elimination. Systemic injection of this protein–corrole complex resulted in tumor accumulation, which can be visualized in vivo due to the red corrole fluorescence. Cytotoxic and cytostatic properties of these targeted Ga(III) corroles were found to be cell-line dependent, with the ability to induce late M-phase arrest in several cancer cell lines (32).Despite the well-known cytotoxic properties of mono- and multinuclear platinum complexes (3335), studies of the antitumor properties of platinum-based SCCs are rare (17, 36). Moreover, recent reports have demonstrated that platinum-based SCCs can act as effective hosts for guests and have interesting photophysical properties (3742). In particular, highly emissive rhomboids based on aniline-containing donors and Pt-based metal acceptors have been developed that display different photophysical properties from those of their constituent subunits (40). These assemblies are interesting targets to investigate the cytotoxicity of organoplatinum SCCs, whereas their emission spectra could be used for interrogating the structural integrity in vitro. Here, for the first time to our knowledge, we report the uptake of SCCs in vitro in cell-based assays, determined by using laser-scanning confocal microscopy, and an in vivo assessment of the anticancer activity of SCCs in mouse s.c. tumor xenograft models.  相似文献   
9.
Worksite health and wellness (WH&W) are gaining popularity in targeting cardiovascular (CV) risk factors among various industries. India is a large country with a larger workforce in the unorganized sector than the organized sector. This imbalance creates numerous challenges and barriers to implementation of WH&W programs in India. Large scale surveys have identified various CV risk factors across various industries. However, there is scarcity of published studies focusing on the effects of WH&W programs in India. This paper will highlight: 1) the current trend of CV risk factors across the industrial community, 2) the existing models of delivery for WH&W in India and their barriers, and 3) a concise evidence based review of various WH&W interventions in India.  相似文献   
10.
Chakraborty K  Khan GA  Banerjee P  Ray U  Sinha AK 《Platelets》2003,14(7-8):421-427
Incubation of platelet-rich plasma with 80 microM aspirin that resulted in the inhibition of both the secondary phase of ADP induced platelet aggregation and prostaglandin synthesis simultaneously stimulated the production of NO in platelets. Furthermore it was found that the treatment of platelet-rich plasma either with 80 microM ibuprofen or salicylic acid, like aspirin, which inhibited the secondary phase of platelet aggregation by ADP and prostaglandin synthesis, also stimulated the production of NO in the absence of added ADP. However the inhibition of prostaglandin synthesis by ibuprofen or salicylic acid, unlike aspirin, was transient in nature. Incubation of washed platelets with any of these three compounds also stimulated NO synthesis indicating that the effect of these compounds was not mediated through plasma proteins. The in vitro effect of aspirin on the increase of NO in platelets could also be demonstrated by in vivo exposure of platelets to the compound. It was concluded that either a temporary or a lasting inhibition of prostaglandin synthesis by these inhibitors resulted in the synthesis of NO in resting platelets. Since NO is a potent inhibitor of platelet aggregation the inhibition of platelet aggregation, by these compounds may not be the consequence of the inhibition of prostaglandin synthesis alone, but could also be related, at least partly, to the stimulated synthesis of NO by these inhibitors.  相似文献   
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