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1.

Background

Cardiopulmonary resuscitation (CPR) is a key component of emergency care following cardiac arrest. A better understanding of factors that influence CPR outcomes and their prognostic implications would help guide care. A retrospective analysis of 800 adult patients that sustained an in- or out-of-hospital cardiac arrest and underwent CPR in the emergency department of a tertiary care facility in Karachi, Pakistan, between 2008 and 15 was conducted.

Methods

Patient demographics, clinical history, and CPR characteristics data were collected. Logistic regression model was applied to assess predictors of return of spontaneous circulation and survival to discharge. Analysis was conducted using SPSS v.21.0.

Results

Four hundred sixty-eight patients met the study’s inclusion criteria, and overall return of spontaneous circulation and survival to discharge were achieved in 128 (27.4%) and 35 (7.5%) patients respectively. Mean age of patients sustaining return of spontaneous circulation was 52 years and that of survival to discharge was 49 years. The independent predictors of return of spontaneous circulation included age ≤?49 years, witnessed arrest, ≤?30 min interval between collapse-to-start, and 1–4 shocks given during CPR (aOR (95% CI) 2.2 (1.3–3.6), 1.9 (1.0–3.7), 14.6 (4.9–43.4), and 3.0 (1.4–6.4) respectively), whereas, age ≤?52 years, bystander resuscitation, and initial rhythm documented (pulseless electrical activity and ventricular fibrillation) were independent predictors of survival to discharge (aOR (95% CI) 2.5 (0.9–6.5), 1.4 (0.5–3.8), 5.3 (1.5–18.4), and 3.1 (1.0–10.2) respectively).

Conclusion

Our study notes that while the majority of arrests occur out of the hospital, only a small proportion of those arrests receive on-site CPR, which is a key contributor to unfavorable outcomes in this group. It is recommended that effective pre-hospital emergency care systems be established in developing countries which could potentially improve post-arrest outcomes. Younger patients, CPR initiation soon after arrest, presenting rhythm of pulseless ventricular tachycardia and ventricular fibrillation, and those requiring up to four shocks to revive are more likely to achieve favorable outcomes.
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Transition metal carbides (TMCs) have recently emerged as competent members among the family of two-dimensional (2D) materials, owing to their promising applications. There are many promising applications of MXenes; however, their magnetic properties lack a wide margin, both experimentally as well as theoretically, which needs to be investigated for potential use in spintronics. In this study, we carried out a comprehensive etching process via selective extraction of Al layers from Nb2AlC-MAX using a wet electrochemical route under well-optimized conditions to obtain fine 2D-Nb2C MXene sheets. Structural analysis using X-ray diffraction (XRD) confirms the effective removal of Al followed by confirmation of a 2D layered structure from morphological analysis using scanning electron microscopy (SEM). Zero-field-cooled (ZFC) and field-cooled (FC) measurements of MAX and MXene at different field strengths were performed using a superconducting quantum interference device (SQUID). Magnetic measurements reveal the paramagnetic nature of Nb2AlC-MAX measured under 5 mT; however, this changes to a clear superconductor-like diamagnetic behavior with a shift of the magnetization from positive to negative values at low temperatures when measured under 5 mT and 10 mT for Nb2C MXene. The diamagnetism, however, is changed to paramagnetism at 100 mT, which shows the existence of critical fields known typically for a type-II superconductor. To gain an insight into this unusual behavior in MXene, density functional theory (DFT) first-principles calculation was also performed in Wein2K software using spin-polarized generalized gradient approximation (sp-GGA). The magnetic moment of the compound is calculated to be negative, which corresponds well with the experimental finding and suggests that the negative magnetic moment originated from the d-orbital of Nb2C. The present report provides a pathway to deeply understanding the existence of superconductivity-like diamagnetic behavior in Nb2C MXene, which is useful for future magnetic applications.

Transition metal carbides (TMCs) have recently emerged as competent members among the family of two-dimensional (2D) materials, owing to their promising applications.

In two-dimensional (2D) materials, magnetism at the nanoscale is at the forefront of many cutting-edge technological applications, such as spintronic devices. Naguib et al. have synthesized a new class of two-dimensional materials, known as MXenes (MnXn+1), discovered in 2011, giving a possibility of magnetism in such 2D materials and their promising uses in spintronic devices.1 These 2D layer structured early transition metal carbides and/or nitrides are known as MXenes, so named to indicate their structural similarities with graphene.2 MXenes are derived from 3D MAX phases (space group P63/mmc) in which “M” is an early transition metal, e.g., Ti, Ta, V, etc.; “A” is mainly a group 13 or group 14 element (group III-A or IV-A), e.g., Si, Al; “X” is a carbide, nitride or can be both; and n = 1, 2, 3 represents the number of layers, forming 211, 312 and 413 phases.3–5 Over the past decade, this new material has gained enormous attention, thus developing an entirely new research field to disclose the properties of the 2D state of this material. The materials in the 2D regime own a cluster of astonishing physical properties as compared to the 3D nature, but intrinsic two-dimensional magnetism has proved to be challenging. As 2D semiconductors have revamped the field of electronics, similarly, magnetism in 2D materials could remodel spintronic devices that can employ a spin degree of freedom.6,7Nb2C MXene was first synthesized by Naguib et al., but they just reported its electrochemical activity as a promising electrode material.4 Further work has been reported in Nb2C with various biomedical applications, energy storage, supercapacitors, and nanoelectronics.9–19 As far as the magnetism in such 2D MXenes is concerned, it remains less investigated, and this research void needs to be filled. Recently, Babar et al. reported the observation of superconductivity in as-prepared powdered Nb2C for the first time, with the highest onset transition temperature Tc,onset = 12.5 K among the MXene family. However, the authors did not discuss the magnetic nature of the parent Nb2AlC MAX itself and did not reason for the presence of unusual magnetic effects in MXene.8 MXenes are favorable members of 2D magnetism, and different magnetic natures are computationally predicted in various carbide and nitride MXenes.7,20 The existence of novel room-temperature ferromagnetic order in doped MXene and the coexistence of different magnetic phases in MXene, along with experimental evidence, indicate its potential of hosting diverse magnetic natures.21,22 Considerable research has been focused on these 2D structures due to their importance and favorable applications, such as spintronics. MXene could provide a vast platform for exploring the magnetic properties and is one of the best candidates that can host superconductivity as compared to other members of the 2D family. Experimental studies are generally dependent upon numerous variables, thus affecting the research pace. However, density functional theory-based first principles calculation and theoretical simulations are a successful way to examine and foresee the properties of low-dimensional materials. This provoked us to theoretically explore superconductivity in Nb2C and their validation through superconductivity measurements of experimentally synthesized Nb2C MXene. In this work, we report a systematic etching mechanism of Nb2C MXene to obtain fine 2D sheets via a chemical etching route using hydrofluoric (HF) acid. Structural and morphological studies using the X-ray diffraction technique (XRD), scanning electron microscopy (SEM) and elemental analysis by energy-dispersive X-ray spectroscopy (EDX) show the effective removal of Al from the parent 3D-Nb2AlC MAX, thus revealing an accordion-like sheet structure. Optical analysis indicates a significant reduction in bandgap after chemical etching. Magnetic properties were carried out to observe the signatures of superconductivity (a perfect diamagnetic state, negative magnetic moment) and its magnetic nature at room temperature. To study the magnetic nature of as-prepared powder-form Nb2C, density functional theory (DFT) first principles calculation was carried out through Wein2K using spin-polarized generalized gradient approximation (sp-GGA). The magnetic moment of the compound is calculated to be −0.00485, which although but small is important, as the value is negative, which is an indication of the presence of diamagnetism in Nb2C. Here, the detailed chemical etching process, magnetic properties of Nb2AlC MAX and its effect on magnetic phase of Nb2C MXene, and the density functional theory calculation are reported, which were not discussed by Babar et al. in ref. 8.  相似文献   
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Dengue virus infection is the most widespread mosquito-borne viral infection in humans and has emerged as a serious global health challenge. In the absence of effective treatment and vaccine, host factors including nutritional status, which may alter disease progression, need investigation. The interplay between nutrition and other infections is well-established, and modulation of nutritional status often presents a simple low-cost method of interrupting transmission, reducing susceptibility, and/or ameliorating disease severity. This review examines the evidence on the role of micronutrients in dengue virus infection. We found critical issues and often inconsistent results across studies; this finding along with the lack of sufficient literature in this field have limited our ability to make any recommendations. However, vitamins D and E have shown promise in small supplementation trials. In summary, the role of micronutrients in dengue virus infection is an exciting research area and needs to be examined in well-designed studies with larger samples.  相似文献   
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Ethnopharmacological relevance

Mercurialis annua L., Bongardia chrysogonum L., and Viscum cruciatum Sieb have been traditionally used by local herbalists in Jordan for the treatment of hematopoietic neoplasms.

Aim of the study

To determine the anti-cancer, anti-inflammatory and anti-microbial potentials of the three extracts against two of the most common hematopoietic malignancies in the Jordanian populations; Burkitt's lymphoma and Multiple myeloma.

Materials and methods

The anti-cancer activity was tested against the two cell lines (BJAB Burkitt's lymphoma and U266 multiple myeloma) using the MTT and trypan blue assays. The agar dilution assay was used to study the anti-microbial activity against Gram-positive bacteria, Gram-negative bacteria, anaerobic bacteria and yeast. The pro-inflammatory cytokines interleukin (IL) -1β, IL-8 and tumor necrosis factor-α (TNF-α) were measured in the pretreated cell lines using ELISA assay to determine the anti-inflammatory activity of Viscum cruciatum Sieb against the two cell lines.

Results

The results show no evidence of stimulation of tumor growth by any of the three extracts comprising cell lines from hematological malignancies, but Viscum cruciatum Sieb showed a selective anticancer activity against BJAB cells, with IC50 value of 14.21 μg/ml. The antimicrobial effect was only noticed with Viscum cruciatum extract by inhibiting Staphylococcus aureus, Candida albicans and Propionibacterium acne, but not Pseudomonas aeruginosa at MIC of 1.25, 1.25, 0.625 and <5 mg/ml, respectively. The highest activity was against the anaerobic bacteria Propionibacterium acne. Viscum cruciatum Sieb extract showed an inhibitory effect on the pro-inflammatory cytokine IL-8, but it increased TNF-α and IL-1β secretions in BJAB cells. Whereas, it had an inhibitory effect on TNF-α and IL-1β cytokines while it enhanced IL-8 secretions in U266 cells.

Conclusion

Among the three tested herbal extracts used in the traditional medicine in Jordan, only Viscum cruciatum Sieb showed high anti-cancer and anti-microbial potentials. They also had an anti-inflammatory effect. These observations raise the prospects of using Viscum cruciatum Sieb for treatment of diseases associated with some bacterial and fungal infections, for imbalanced cytokine production and for enhancing cancer and other immunotherapies.  相似文献   
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Epidermoid carcinoma (also known as squamous cell carcinoma) of the parotid gland is more prevalent among the elderly, as are other head and neck tumors. In most cases it is observed either as a nodal metastasis of a primary tumor that drains into the parotid area or as a direct extension of a tumor that has originated in the upper dermis. Primary epidermoid carcinomas arising directly from the parotid gland are extremely rare. Similarly, secondary invasion of the orbital region by a neighboring tumor is more common than primary epidermoid carcinoma of the orbit, which is also rare. In this article, we discuss the diagnosis and treatment of a rare case of epidermoid carcinoma simultaneously invading the parotid gland and the orbit.  相似文献   
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