China
Africa
Explore chapters and articles related to this topic
Fungi
Published in Harriet A. Burge, Bioaerosols, 2020
Infection rates following hip and knee replacement surgery can be as high as 10% (Lidwell et al., 1982), and infections can surface months or even years after the operation (Charnley, 1973). The increasing use of bone marrow transplants to treat patients with acute leukemia and other forms of cancer, severe aplastic anemia, and congenital and acquired immunodeficiencies, as well as other disorders, is associated with an increase of infections due to a variety of pathogens (Arlet et al., 1989). Prior to and following transplants, patients are given immunosuppressive drugs to prevent rejection. In addition, in the case of leukemia, the patient may also be given total body irradiation to destroy malignant cells. All during this time, but especially just following transplant, the patient is at high risk for many opportunistic infections (Streifel et al., 1989; Young et al., 1970). Epidemics of nosocomial opportunistic fungal infection have occurred that provide proof of airborne spread. The fungi involved are ubiquitous saprobes in the environment and are usually considered nonpathogenic. The normal method of dissemination of these fungi is through airborne spores. Aspergillus is the most frequently reported opportunistic pathogen, while Fusarium infections have only only recently been identified. Because of the widespread occurrence of these genera, the remainder of this discussion focuses on these opportunistic infections.
Hematopoietic Stem Cell Transplantation in Patients with Autoimmune Bullous Skin Disorders
Published in Richard K. Burt, Alberto M. Marmont, Stem Cell Therapy for Autoimmune Disease, 2019
Introduction of corticosteroids has greatly reduced mortality, but significant morbidity still remains. Many steroid regimens with or without immunosuppressive drugs have been tried. Patients with only oral lesions can be treated with topical steroids and oral hygiene. Patients with widespread disease need systemic corticosteroids. In general, the dosage recommended is prednisolone 1.0-1.5 mg/kg/day in combination with topical or intralesional steroids. Dosage will be adjusted based on clinical response, and the titer of circulating pemphigus antibody can be of help as an adjunctive tool for dosage adjustment. If disease is not controlled with this regimen, various dosage recommendations exist, such as higher daily dose or monthly pulse intravenous steroids. As an adjunctive treatment for steroids or as steroid-sparing agents, various immunosuppressive drugs are suggested including azathioprine, cyclophosphamide, gold, cyclosporin, methotrexate and mycophenolate mofetil. Plasmapheresis has been tried and showed variable responses. Intravenous immunoglobulin may also be a safe alternative modality for steroid-sparing effect in some recalcitrant cases.16
Immobilization of Biomolecules
Published in Anil Kumar Anal, Bionanotechnology, 2018
The immunoprotection of transplanted cells offers transplantation without the need of immunosuppression of the host. Moreover, immunoisolation of a xenograft, for example, a transplant of cells from nonhuman species, has been suggested as a way of overcoming the limited supply of human organs for transplantation (O’Shea and Sun 1986; Lum et al. 1991; Lum et al. 1992; Wang et al. 1997). The membranes used for encapsulation of living cells must be biocompatible and immunocompatible to the recipient and to the cells it encloses. The materials used in biomedical and pharmaceutical products reflect complex characteristics that influence the fate of the material in its biological host. However, the ability of the host to accept the material depends not only on the material itself but also on the host, its genetic depositions, and physical status (Granicka et al. 1996; Lanza et al 1999). The device used for encapsulation should not evoke fibrous tissue reaction, macrophage activation, and cytotoxic agent release (Rihová 2000; Lee et al. 2009a).
Novel electrospun conduit based on polyurethane/collagen enhanced by nanobioglass for peripheral nerve tissue engineering
Published in Journal of Biomaterials Science, Polymer Edition, 2022
Somayeh Tofighi Nasab, Nasim Hayati Roodbari, Vahabodin Goodarzi, Hossein Ali Khonakdar, Kourosh Mansoori, Mohammad Reza Nourani
Peripheral nerve injury (PNI) is a clinical issue that leads to long-term organ dysfunction. The main therapeutic goal for the severed peripheral nerves is to reconstruct the extension of the damaged nerve to regenerate and establish physiological communication. The use of autograft (a gold-standard method) is considered an effective method for repairing injured nerves, nevertheless, due to some limitations, the use of this approach is limited, and the long waiting time for organ and tissue transplantations as well as disease transmission urges a need for a new method to overcome these limitations [1]. Besides, recipients of this type of transplant must receive immunosuppressive agents for the entire life span, regardless of the high risk of infection, tumor formation, and adverse side effects [2]. As one of the leading methods in modern medicine, tissue engineering is a rapidly growing field of research. In order to accomplish tissue regeneration, three key factors must be taken into account, namely cells, scaffolds, and biomolecules, such as growth factors and genes [3]. In tissue engineering, there is a permanent solution for the treatment of impaired tissues, so there is no need for complementary therapies, and as a result, treatment costs are greatly reduced [4]. Although much research has been performed over the past century to seek new strategies to repair peripheral nerves, there is currently no satisfactory method to meet the desired criteria for peripheral nerve recovery.
Medical textiles
Published in Textile Progress, 2020
Transplantation of the kidney is undertaken for advanced chronic renal failure. The aim is to transplant a functioning kidney such that dialysis is no longer required. Lifelong immunosuppression is used to prevent rejection [608]. There are problems with all forms of renal replacement therapy. Haemodialysis hinders mobility and limits activities of daily life. Peritoneal dialysis does the same but tends to affect quality of life more than mobility. Both carry a risk of infection and failure of dialysis. Transplantation requires a carefully matched kidney and life-long immunosuppression. Thus, the ability to design an artificial functioning kidney would have great promise [640].
Key characteristics of 86 agents known to cause cancer in humans
Published in Journal of Toxicology and Environmental Health, Part B, 2019
Daniel Krewski, Michael Bird, Mustafa Al-Zoughool, Nicholas Birkett, Mélissa Billard, Brittany Milton, Jerry M. Rice, Yann Grosse, Vincent J. Cogliano, Mark A. Hill, Robert. A. Baan, Julian Little, Jan M. Zielinski
Immunosuppression is an induced reduction in the capacity of the immune system to respond effectively to foreign antigens, including antigens on tumor cells. In contrast to other key characteristics, immune suppression does not play a direct part in transforming normal cells into tumor cells, but enables them to escape immune surveillance. Among other roles, the immune system also plays a major part in the inflammatory response to injury.