Tehran University of Medical Sciences

About: Tehran University of Medical Sciences is a education organization based out in Tehran, Iran. It is known for research contribution in the topics: Population & Medicine. The organization has 35661 authors who have published 57234 publications receiving 878523 citations. The organization is also known as: TUMS.

Deleterious Mutations in LRBA Are Associated with a Syndrome of Immune Deficiency and Autoimmunity

Abstract: Most autosomal genetic causes of childhood-onset hypogammaglobulinemia are currently not well understood. Most affected individuals are simplex cases, but both autosomal-dominant and autosomal-recessive inheritance have been described. We performed genetic linkage analysis in consanguineous families affected by hypogammaglobulinemia. Four consanguineous families with childhood-onset humoral immune deficiency and features of autoimmunity shared genotype evidence for a linkage interval on chromosome 4q. Sequencing of positional candidate genes revealed that in each family, affected individuals had a distinct homozygous mutation in LRBA (lipopolysaccharide responsive beige-like anchor protein). All LRBA mutations segregated with the disease because homozygous individuals showed hypogammaglobulinemia and autoimmunity, whereas heterozygous individuals were healthy. These mutations were absent in healthy controls. Individuals with homozygous LRBA mutations had no LRBA, had disturbed B cell development, defective in vitro B cell activation, plasmablast formation, and immunoglobulin secretion, and had low proliferative responses. We conclude that mutations in LRBA cause an immune deficiency characterized by defects in B cell activation and autophagy and by susceptibility to apoptosis, all of which are associated with a clinical phenotype of hypogammaglobulinemia and autoimmunity.

Barriers and facilitators to the implementation of lay health worker programmes to improve access to maternal and child health: qualitative evidence synthesis

Abstract: Background Lay health workers (LHWs) perform functions related to healthcare delivery, receive some level of training, but have no formal professional or paraprofessional certificate or tertiary education degree. They provide care for a range of issues, including maternal and child health. For LHW programmes to be effective, we need a better understanding of the factors that influence their success and sustainability. This review addresses these issues through a synthesis of qualitative evidence and was carried out alongside the Cochrane review of the effectiveness of LHWs for maternal and child health. Objectives The overall aim of the review is to explore factors affecting the implementation of LHW programmes for maternal and child health. Search methods We searched MEDLINE, OvidSP (searched 21 December 2011); MEDLINE Ovid In-Process & Other Non-Indexed Citations, OvidSP (searched 21 December 2011); CINAHL, EBSCO (searched 21 December 2011); British Nursing Index and Archive, OvidSP (searched 13 May 2011). We searched reference lists of included studies, contacted experts in the field, and included studies that were carried out alongside the trials from the LHW effectiveness review. Selection criteria Studies that used qualitative methods for data collection and analysis and that focused on the experiences and attitudes of stakeholders regarding LHW programmes for maternal or child health in a primary or community healthcare setting. Data collection and analysis We identified barriers and facilitators to LHW programme implementation using the framework thematic synthesis approach. Two review authors independently assessed study quality using a standard tool. We assessed the certainty of the review findings using the CerQual approach, an approach that we developed alongside this and related qualitative syntheses. We integrated our findings with the outcome measures included in the review of LHW programme effectiveness in a logic model. Finally, we identified hypotheses for subgroup analyses in future updates of the review of effectiveness. Main results We included 53 studies primarily describing the experiences of LHWs, programme recipients, and other health workers. LHWs in high income countries mainly offered promotion, counselling and support. In low and middle income countries, LHWs offered similar services but sometimes also distributed supplements, contraceptives and other products, and diagnosed and treated children with common childhood diseases. Some LHWs were trained to manage uncomplicated labour and to refer women with pregnancy or labour complications. Many of the findings were based on studies from multiple settings, but with some methodological limitations. These findings were assessed as being of moderate certainty. Some findings were based on one or two studies and had some methodological limitations. These were assessed have low certainty. Barriers and facilitators were mainly tied to programme acceptability, appropriateness and credibility; and health system constraints. Programme recipients were generally positive to the programmes, appreciating the LHWs’ skills and the similarities they saw between themselves and the LHWs. However, some recipients were concerned about confidentiality when receiving home visits. Others saw LHW services as not relevant or not sufficient, particularly when LHWs only offered promotional services. LHWs and recipients emphasised the importance of trust, respect, kindness and empathy. However, LHWs sometimes found it difficult to manage emotional relationships and boundaries with recipients. Some LHWs feared blame if care was not successful. Others felt demotivated when their services were not appreciated. Support from health systems and community leaders could give LHWs credibility, at least if the health systems and community leaders had authority and respect. Active support from family members was also important. Health professionals often appreciated the LHWs’ contributions in reducing their workload and for their communication skills and commitment. However, some health professionals thought that LHWs added to their workload and feared a loss of authority. LHWs were motivated by factors including altruism, social recognition, knowledge gain and career development. Some unsalaried LHWs wanted regular payment, while others were concerned that payment might threaten their social status or lead recipients to question their motives. Some salaried LHWs were dissatisfied with their pay levels. Others were frustrated when payment differed across regions or institutions. Some LHWs stated that they had few opportunities to voice complaints. LHWs described insufficient, poor quality, irrelevant and inflexible training programmes, calling for more training in counselling and communication and in topics outside their current role, including common health problems and domestic problems. LHWs and supervisors complained about supervisors’ lack of skills, time and transportation. Some LHWs appreciated the opportunity to share experiences with fellow LHWs. In some studies, LHWs were traditional birth attendants who had received additional training. Some health professionals were concerned that these LHWs were over-confident about their ability to manage danger signs. LHWs and recipients pointed to other problems, including women’s reluctance to be referred after bad experiences with health professionals, fear of caesarean sections, lack of transport, and cost. Some LHWs were reluctant to refer women on because of poor co-operation with health professionals. We organised these findings and the outcome measures included in the review of LHW programme effectiveness in a logic model. Here we proposed six chains of events where specific programme components lead to specific intermediate or long-term outcomes, and where specific moderators positively or negatively affect this process. We suggest how future updates of the LHW effectiveness review could explore whether the presence of these components influences programme success. Authors' conclusions Rather than being seen as a lesser trained health worker, LHWs may represent a different and sometimes preferred type of health worker. The close relationship between LHWs and recipients is a programme strength. However, programme planners must consider how to achieve the benefits of closeness while minimizing the potential drawbacks. Other important facilitators may include the development of services that recipients perceive as relevant; regular and visible support from the health system and the community; and appropriate training, supervision and incentives.

Methods for preparation and activation of activated carbon: a review

Abstract: Activated carbon refers to a wide range of carbonised materials of high degree of porosity and high surface area. Activated carbon has many applications in the environment and industry for the removal, retrieval, separation and modification of various compounds in liquid and gas phases. Selection of the chemical activator agent is a major step controlling the performance and applicability of activated carbon. Here, we review chemical activators used to produce activated carbon. We compare the impregnation method with the physical mixing method used in activating with alkali hydroxides. We selected 81 articles from Google Scholar, PubMed, Scopus, Science Direct, Embase and Medlin databases. Eighteen articles report the activation with potassium hydroxide, 17 with phosphoric acid, 15 with zinc chloride, 11 with potassium carbonate, nine with sodium hydroxide, and 11 with new activating agents. Activation with phosphoric acid is commonly used for lignocellulosic material and at lower temperatures. Zinc chloride generates more surface area than phosphoric acid but is used less due to environmental concerns. Potassium carbonate, in comparison with potassium hydroxide, produces higher yields and a higher surface area for the adsorption of large pollutant molecules such as dyes. Activating with potassium hydroxide in terms of surface area and efficiency shows better results than sodium hydroxide for various applications. Also, the comparison of the physical mixing method and the impregnation method in activation with alkali metals indicates that the activated carbon obtained through physical mixing had a higher porosity than the activated carbon produced by the impregnation method.

Cyclooxygenase-2 in cancer: A review.

Abstract: Cyclooxygenase-2 (COX-2) is frequently expressed in many types of cancers exerting a pleiotropic and multifaceted role in genesis or promotion of carcinogenesis and cancer cell resistance to chemo- and radiotherapy. COX-2 is released by cancer-associated fibroblasts (CAFs), macrophage type 2 (M2) cells, and cancer cells to the tumor microenvironment (TME). COX-2 induces cancer stem cell (CSC)-like activity, and promotes apoptotic resistance, proliferation, angiogenesis, inflammation, invasion, and metastasis of cancer cells. COX-2 mediated hypoxia within the TME along with its positive interactions with YAP1 and antiapoptotic mediators are all in favor of cancer cell resistance to chemotherapeutic drugs. COX-2 exerts most of the functions through its metabolite prostaglandin E2. In some and limited situations, COX-2 may act as an antitumor enzyme. Multiple signals are contributed to the functions of COX-2 on cancer cells or its regulation. Members of mitogen-activated protein kinase (MAPK) family, epidermal growth factor receptor (EGFR), and nuclear factor-κβ are main upstream modulators for COX-2 in cancer cells. COX-2 also has interactions with a number of hormones within the body. Inhibition of COX-2 provides a high possibility to exert therapeutic outcomes in cancer. Administration of COX-2 inhibitors in a preoperative setting could reduce the risk of metastasis in cancer patients. COX-2 inhibition also sensitizes cancer cells to treatments like radio- and chemotherapy. Chemotherapeutic agents adversely induce COX-2 activity. Therefore, choosing an appropriate chemotherapy drugs along with adjustment of the type and does for COX-2 inhibitors based on the type of cancer would be an effective adjuvant strategy for targeting cancer.