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1.
Alzheimer’s disease is characterized by the extracellular accumulation of the amyloidβin the form of amyloid plaques and the intracellular deposition of the microtubule-associated protein tau in the form of neurofibrillary tangles.Most of the Alzheimer’s drugs targeting amyloidβhave been failed in clinical trials.Particularly,tau pathology connects greatly in the pathogenesis of Alzheimer’s disease.Tau protein enhances the stabilization of microtubules that leads to the appropriate function of the neuron.Changes in the quantity or the conformation of tau protein could affect its function as a microtubules stabilizer and some of the processes wherein it is involved.The molecular mechanisms leading to the accumulation of tau are principally signified by numerous posttranslational modifications that change its conformation and structural state.Therefore,aberrant phosphorylation,as well as truncation of tau protein,has come into focus as significant mechanisms that make tau protein in a pathological entity.Furthermore,the shape-shifting nature of tau advocates to comprehend the progression of Alzheimer’s disease precisely.In this review,we emphasize the recent studies about the toxic and shape-shifting nature of tau in the pathogenesis of Alzheimer’s disease.  相似文献   
2.
Autologous blood stem cell transplants (ABSCT) are increasingly used for the treatment of haematological malignancies. The use of hemopoietic growth factors, in conjunction with stem cell mobilization by chemotherapeutic agents, has permitted successful harvests requir ing only a few leukaphereses; cells mobilized in this manner contain a relatively large number of committed precursors of all lineages, as well as early progenitor cells capable of main taining long-term haemopoiesis. Haematological recovery after ABSCT is rapid, thereby sig nificantly shortening the period of post-chemotherapy neutropenia and thrombocytopenia. Furthermore, blood-derived grafts may contain fewer malignant cells than the bone marrow cells. The preliminary results have been so encouraging that it is envisaged that in myeloma, Hodgkin's disease and non-Hodgkin lymphomas, ABSCT may eventually replace autologous marrow transplantation.  相似文献   
3.
Breast fat necrosis (BFN) is usually a benign inflammatory response to breast trauma. However, an extremely rare cause of fat necrosis is calciphylaxis, a calcification of small- and medium-sized arteries causing thrombosis and ischemia. It is classified into (A) uremic (B) nonuremic-induced calciphylaxis. Calciphylaxis has been reported to be encountered in different parts of the body. However, to the best of our knowledge there is only one case in the English literature of BFN 2ry to warfarin-induced calciphylaxis. We report a 65-year-old female, known case of atrial fibrillation on warfarin, presented with a left breast mass of 4-month duration. The mass was painful and progressively enlarging. Examination of the left breast showed 7 × 4 cm mass, spanning from 10-2 o'clock, free from surrounding structures, with preserved overlying skin. However, the mass was not visualized on mammogram. Ultrasound showed a left breast lobulated hypoechoic mass containing a hyperechoic component. Biopsy showed fat necrosis. After 1 month, she presented with ulceration of the overlying skin. After wide local excision, histopathology demonstrated a calciphylaxis-induced fat necrosis. Considering the patient's background, the diagnosis was BFN secondary to warfarin-induced calciphylaxis. Hence, the warfarin was shifted to Rivaroxaban, 6 months follow-up showed no evidence of recurrence. In conclusion, the rarity of nonuremic calciphylaxis is reflected on the delay of diagnosis in some of the reported cases and the lack of grading system used to guide the management of such difficult wounds. However, keeping a high index of suspicion is important whenever such wounds are encountered with presence of risk factors other than end-stage kidney disease.  相似文献   
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Malnutrition contributes to direct and indirect causes of maternal mortality, which is particularly high in Afghanistan. Women's nutritional status before, during, and after pregnancy affects their own well‐being and mortality risk and their children's health outcomes. Though maternal nutrition interventions have documented positive impact on select child health outcomes, there are limited data regarding the effects of maternal nutrition interventions on maternal health outcomes globally. This scoping review maps policies, data, and interventions aiming to address poor maternal nutrition outcomes in Afghanistan. We used broad search categories and approaches including database and website searches, hand searches of reference lists from relevant articles, policy and programme document requests, and key informant interviews. Inclusion and exclusion criteria were developed by type of source document, such as studies with measures related to maternal nutrition, relevant policies and strategies, and programmatic research or evaluation by a third party with explicit interventions targeting maternal nutrition. We abstracted documents systematically, summarized content, and synthesized data. We included 20 policies and strategies, 29 data reports, and nine intervention evaluations. The availability of maternal nutrition intervention data and the inclusion of nutrition indicators, such as minimum dietary diversity, have increased substantially since 2013, yet few nutrition evaluations and population surveys include maternal outcomes as primary or even secondary outcomes. There is little evidence on the effectiveness of interventions that target maternal nutrition in Afghanistan. Policies and strategies more recently have shifted towards multisectoral efforts and specifically target nutrition needs of adolescent girls and women of reproductive age. This scoping review presents evidence from more than 10 years of efforts to improve the maternal nutrition status of Afghan women. We recommend a combination of investments in measuring maternal nutrition indicators and improving maternal nutrition knowledge and behaviours.  相似文献   
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Hormesis, a biphasic dose–response phenomenon, which is characterized by stimulation of an end point at a low‐dose and inhibition at a high‐dose. In the present study we used human lungs fibroblast (HELF) cells as a test model to evaluate the role of oxidative stress (OS) in hormetic effects of non coplanar PCB 101. Results from 3‐(4,5‐dime‐thylthiazol‐2‐yl)‐2,5‐diphenyltetrazo‐lium bromide (MTT) assay indicated that PCB101 at lower concentrations (10?5 to 10?1 μg mL?1) stimulated HELF cell proliferation and inhibited at high concentrations (1, 5, 10, and 20 μg mL?1) in a dose‐ and time‐dependent manner. Reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) (except 48 h) showed a significant increase at higher concentrations of PCB 101 than those at the lower concentrations with the passage of time. Antioxidant enzymes such as glutathione peroxidase (GSH‐Px) exhibited decreasing trends in dose and time dependent manner. Lipid peroxidation assay resulted in a significant increase (P < 0.05) of MDA level in PCB 101‐treated HELF cells compared with controls, suggesting that OS plays a key role in PCB 101‐induced toxicity. Comet assay indicated a significant increase in genotoxicity at higher concentrations of PCB 101 exposure compared to lower concentrations. Overall, we found that HELF cell proliferation was higher at low ROS level and vice versa, which revealed activation of cell signaling‐mediated hormetic mechanisms. The results suggested that PCB 101 has hormetic effects to HELF cells and these were associated with oxidative stress. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1385–1392, 2015.  相似文献   
8.

Objective

We aimed to investigate the effect of known heart disease on post‐out‐of‐hospital cardiac arrest (OHCA) survival outcomes, and its association with factors influencing survival.

Methods

This was an observational, retrospective study involving an OHCA database from seven Asian countries in 2009–2012. Heart disease was defined as a documented diagnosis of coronary artery disease or congenital heart disease. Patients with non‐traumatic arrests for whom resuscitation was attempted and with known medical histories were included. Differences in demographics, arrest characteristics and survival between patients with and without known heart disease were analysed. Multivariate logistic regression was performed to identify factors influencing survival to discharge.

Results

Of 19 044 eligible patients, 5687 had known heart disease. They were older (77 vs 72 years) and had more comorbidities like diabetes (40.9 vs 21.8%), hypertension (60.6 vs 36.0%) and previous stroke (15.2 vs 10.1%). However, they were not more likely to receive bystander cardiopulmonary resuscitation (P = 0.205) or automated external defibrillation (P = 0.980). On univariate analysis, known heart disease was associated with increased survival (unadjusted odds ratio 1.16, 95% confidence interval 1.03–1.30). However, on multivariate analysis, heart disease predicted poorer survival (adjusted odds ratio 0.76, 95% confidence interval 0.58–1.00). Other factors influencing survival corresponded with previous reports.

Conclusions

Known heart disease independently predicted poorer post‐OHCA survival. This study may provide information to guide future prospective studies specifically looking at family education for patients with heart disease and the effect on OHCA outcomes.  相似文献   
9.
Background

Long-acting reversible contraceptives, such as the intrauterine device (IUD), remain underutilised in Pakistan with high discontinuation rates. Based on a 24-month prospective client follow-up (nested within a larger quasi-experimental study), this paper presents the comparison of two intervention models, one using private mid-level providers branded as “Suraj” and the other using community midwives (CMWs) of Maternal Newborn and Child Health Programme, for method continuation among IUD users. Moreover, determinants of IUD continuation and the reasons for discontinuation, and switching behaviour were studied within each arm.

Methods

A total of 1,163 IUD users, 824 from Suraj and 339 from the CMW model, were enrolled in this 24-month prospective client follow-up. Participants were followed-up by female community mobilisers physically every second month to ascertain continued IUD usage and to collect information on associated factors, switching behaviour, reasons for discontinuation, and pregnancy occurrence. The probabilities of IUD continuation and the risk factors for discontinuation were estimated by life table analysis and Cox proportional-hazard techniques, respectively.

Results

The cumulative probabilities of IUD continuation at 24 months in Suraj and CMW models were 82% and 80%, respectively. The difference between the two intervention areas was not significant. The probability distributions of IUD continuation were also similar in both interventions (Log rank test: χ2 = 0.06, df = 1, P = 0.81; Breslow test: χ2 = 0.6, df = 1, P = 0.44). Health concerns (Suraj = 57.1%, CMW = 38.7%) and pregnancy desire (Suraj = 29.3%, CMW = 40.3%) were reported as the most prominent reasons for IUD discontinuation in both intervention arms. IUD discontinuation was significantly associated with place of residence in Suraj and with age (15–25 years) in the CMW model.

Conclusion

CMWs and private providers are equally capable of providing quality IUD services and ensuring higher method continuation. Pakistan’s National Maternal Newborn and Child Health programme should consider training CMWs and providing IUDs through them. Moreover, private sector mid-level providers could be engaged in promoting the use of IUDs.

  相似文献   
10.
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