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51.
Jochen Moll Christian Kexel Hamed Milanchian Mit Balvantray Bhavsar John Howard Barker 《Ultrasound in medicine & biology》2019,45(2):605-611
Approximately 6.3 million fractures occur each year in the United States alone. Accurately monitoring the progression of fracture healing is essential to be able to advise patients when it is safe to return to normal activity. The most common method used to confirm and monitor fracture healing is the acquisition of multiple radiographic images over the many months required for healing. This imaging method uses large expensive equipment and exposes patients to high levels of ionizing radiation. In the study described here, we tested another technology for monitoring fracture healing that could minimize the need for multiple radiographic images. We tested a piezoelectric transducer fixed to the surface of a bone that uses electromechanical impedance spectroscopy to measure simulated fractures and transmits the measurement data to an acoustic receiver located externally on the skin surface. 相似文献
52.
Is toombak a risk factor for oral leukoplakia and oral squamous cell carcinoma ? A systematic review
53.
Virus Genes - Recently, treatment of HCV infection has been improved after the development of direct acting antivirals (DAAs) which target different viral proteins (NS3-4A, NS5A and NS5B). The... 相似文献
54.
55.
R De Freitas Jr MsM FBSC H Hamed FRCS I Fentiman MD FRCS 《International journal of clinical practice》1992,46(3):187-190
Fine needle aspiration cytology is a safe diagnostic technique for breast cancer and can identify certain benign lesions, which can be excised without affecting surrounding tissue. The combination of experienced operator and cytologist can yield high sensitivity and specificity, together with important prognostic information. 相似文献
56.
Breast cancer is the prevalent cancer worldwide. Excessive exposure to endogenous estrogen across a woman's lifespan contributes to and may be a causal factor in breast cancer. Tamoxifen is a mixed estrogen agonist and antagonist, which is used in treatment and prevention of breast cancer as an estrogen antagonist. Many patients experience resistance to tamoxifen for which many mechanisms have been suggested. Endothelin-1 acts as a mitogen for human breast fibroblasts and it affects tumor cell proliferation, invasion, angiogenesis, neovascularization, mitogenesis, and apoptosis inhibition. Previous studies have shown that estradiol is effective in inhibiting endothelin synthesis in breast tissue and cardiovascular system. Tamoxifen as an estrogen receptor (ER) agonist in cardiovascular system has a cardioprotective effect and decreases endothelin level as a vasoconstrictor in cardiovascular system. But in breast tissue tamoxifen acts as an ER antagonist. According to the role of endothelin in breast cancer and inhibitory effect of estrogen on endothelin, we hypothesized that tamoxifen causes increasing in endothelin level or endothelin receptors probably by inhibitory effect on ER in breast tissue, leading to tamoxifen resistance. Therefore a combination of tamoxifen with endothelin antagonist seems to be a reasonable therapeutic strategy. 相似文献
57.
John G. Mina Ssu-Ying Pan Nilu K. Wansadhipathi Catherine R. Bruce Hosam Shams-Eldin Ralph T. Schwarz Patrick G. Steel Paul W. Denny 《Molecular and biochemical parasitology》2009,168(1):16-23
Sphingolipids are important components of eukaryotic membranes, particularly the plasma membrane, and are involved in a diverse array of signal transduction processes. In the Eukaryota the biosynthetic pathway for the formation of these lipid species is largely conserved. However, in contrast to mammals which produce sphingomyelin (SM), several pathogenic fungi and protozoa synthesize inositol phosphorylceramide (IPC) as the primary phosphosphingolipid. This process is catalyzed by the enzyme IPC synthase, a recognized target for anti-fungals encoded by the AUR1 gene in yeast. Recently, functional orthologues of the AUR1p have been identified in a group of insect vector-borne pathogenic protozoa, the Kinetoplastida, which are responsible for a range of so-called neglected diseases. Of these the Trypanosoma brucei species are the causative agents of human African trypanosomiasis in many of the most under-developed regions of Africa. The available treatments for these diseases are limited, of decreasing efficacy, and often demonstrate severe side-effects. Against this background the T. brucei sphingolipid synthase, an orthologue of the yeast AUR1p, may represent a promising target for novel anti-protozoals. Our studies identify an isoform of this protein as a novel bi-functional enzyme capable of catalyzing the synthesis of both IPC and SM, both known to be present in the parasite. Furthermore, the synthase is essential for parasite growth and can be inhibited by a known anti-fungal at low nanomolar levels in vitro. Most notably this drug demonstrates trypanocidal activity against cultured bloodstream form parasites. Thus, the T. brucei sphingolipid synthase represents a valid and promising drug target. 相似文献
58.
Requirements for the development of IL-4-producing T cells during intestinal nematode infections: what it takes to make a Th2 cell in vivo 总被引:1,自引:0,他引:1
Zhugong Liu Qian Liu John Pesce Robert M. Anthony Erika Lamb Jeannette Whitmire Hossein Hamed Motoko Morimoto Joseph F. Urban Jr William C. Gause 《Immunological reviews》2004,201(1):57-74
Summary: Components of the type 2 immune response may mediate host protection against both helminthic parasites and harmful allergic responses. A central player in this response is the T‐helper 2 (Th2) effector cell, which produces interleukin (IL)‐4, IL‐5, IL‐13, and other Th2 cytokines during the primary and memory response. Specific aspects of the parasite that trigger Th2‐cell differentiation are not yet defined. Furthermore, the cell types and cell surface and secreted molecules that provide the immune milieu required for the development of Th2 effector cells and also Th2 memory cells are not well understood. They will probably vary with the particular helminth or other antigen inducing the Th2 response. We have used third stage larvae of intestinal nematode parasites as adjuvants to promote naïve nonparasite antigen‐specific T cells to differentiate into Th2 cells. This model system avoids possible parasite antigen‐specific T‐cell clones or cross‐reactive memory T cells that may preferentially differentiate into Th2 effector cells during the course of infection and confound the stereotypical components of parasite‐induced Th2 cell differentiation. We have found that these parasites have a potent adjuvant effect and have used our model system to begin to investigate the events that lead to the development of polarized Th2 cells in vivo. 相似文献
59.
Delorenzi M Sexton A Shams-Eldin H Schwarz RT Speed T Schofield L 《Infection and immunity》2002,70(8):4510-4522
About 2.5 million people die of Plasmodium falciparum malaria every year. Fatalities are associated with systemic and organ-specific inflammation initiated by a parasite toxin. Recent studies show that glycosylphosphatidylinositol (GPI) functions as the dominant parasite toxin in the context of infection. GPIs also serve as membrane anchors for several of the most important surface antigens of parasite invasive stages. GPI anchoring is a complex posttranslational modification produced through the coordinated action of a multicomponent biosynthetic pathway. Here we present eight new genes of P. falciparum selected for encoding homologs of proteins essential for GPI synthesis: PIG-A, PIG-B, PIG-M, PIG-O, GPI1, GPI8, GAA-1, and DPM1. We describe the experimentally verified mRNA and predicted amino acid sequences and in situ localization of the gene products to the parasite endoplasmic reticulum. Moreover, we show preliminary evidence for the PIG-L and PIG-C genes. The biosynthetic pathway of the malaria parasite GPI offers potential targets for drug development and may be useful for studying parasite cell biology and the molecular basis for the pathophysiology of parasitic diseases. 相似文献
60.
Maryam Monajemzadeh Mohammad-Taghi Hagghi-Ashtiani Laleh Montaser-Kouhsari Hamed Ahmadi Heidar Zargoosh Mehdi Kalantari 《Iranian journal of pediatrics.》2011,21(4):485-490